Shinji YOKOGAWA

Info-Powered Energy System Research CenterProfessor
Department of InformaticsProfessor
Cluster I (Informatics and Computer Engineering)Professor
  • Profile:
    Shinji Yokogawa is currently associate professor of The Info-Powered Energy System Research Center (iPERC) at The University of Electro-Communications, Tokyo, Japan.

    He received the B.S.(1992), M.S.(1994), and Ph.D.(2008) in engineering from The University of Electro- Communications.

    In 1994, he joined NEC Corp. (later to become NEC Electronics Corp. and Renesas Electronics Corp.), Japan as an engineer and has since been working in the area of reliability. He focused on electromigration, stress-induced voiding, low-k ILD TDDB, and MOL CA-to-PC TDDB issues for 130, 90, 65, 55, 45, 40, 32 and 28 nm technology developments. From 2008 until 2013, he managed the reliability development team in NEC Electronics Corp. mainly focusing on the development of standard CMOS process and embedded DRAM technology. From 2013 to 2016, he worked at Polytechnic University administered by the ministry of health, labour and welfare, Kodaira, Japan.

    From April in 2016, he has been working at The University of Electro-Communications.

    His research interests include device reliability (Lithium-ion battery, power device, etc.), quality control, and reliability theory.

    He has (co)authored over 60 technical papers and serves as a technical committee member and reviewer for leading conferences and journals.

Degree

  • 修士(工学), 電気通信大学
  • Master in Engineering, The University of Electro-Communications
  • 博士(工学), 電気通信大学
  • Ph.D. in Engineering, The University of Electro-Communications

Research Keyword

  • エネルギー貯蔵・制御、品質管理、信頼性工学、機器の寿命予測、故障物理

Field Of Study

  • Manufacturing technology (mechanical, electrical/electronic, chemical engineering), Electronic devices and equipment
  • Social infrastructure (civil Engineering, architecture, disaster prevention), Safety engineering
  • Social infrastructure (civil Engineering, architecture, disaster prevention), Social systems engineering

Career

  • May 2021 - Present
    The University of Electro-Communications, Info-Powered Energy System Research Center, Director
  • Apr. 2019 - Present
    The University of Electro-Communications, Info-Powered Energy System Research Center, Professor
  • 01 Apr. 2016 - 31 Mar. 2019
    電気通信大学, i-パワードエネルギー・システム研究センター, 准教授
  • 01 Apr. 2013 - 31 Mar. 2016
    Polytechnic University of Japan, 生産管理系, Associate professor
  • 01 Apr. 2010 - 31 Mar. 2013
    Renesas Electronics Corporation, デバイス・解析技術統括部デバイスソリューション開発部信頼性技術課, 課長
  • 01 Nov. 2002 - 31 Mar. 2010
    NEC Electronics Corporation
  • 01 Apr. 1994 - 30 Oct. 2002
    NEC Corporation

Educational Background

  • 01 Apr. 1992 - 31 Mar. 1994
    The University of Electro-Communications, 電気通信学研究科, 電子情報学専攻, Japan
  • 01 Apr. 1988 - 23 Mar. 1992
    The University of Electro-Communications, 電気通信学部, 電子情報学科
  • 01 Apr. 1985 - 23 Mar. 1988
    愛媛県立新居浜西高等学校, 普通科

Member History

  • Jan. 2023 - Present
    Chair, IEEE Reliability Society Japan Joint Chapter, Society
  • May 2019 - Present
    理事, 日本信頼性学会
  • Jun. 2016 - Present
    幹事補佐, 電子情報通信学会信頼性研究会, Society
  • 01 Apr. 2019 - 31 Mar. 2020
    2019 GOOD FACTORY賞審査委員, 2019 GOOD FACTORY賞審査委員会, Others
  • 01 Sep. 2019 - 28 Feb. 2020
    JAXA/HIREC 民生コンポーネント活用検討会委員, JAXA/HIREC 民生コンポーネント活用検討会, Others
  • 01 Sep. 2018 - 28 Feb. 2019
    JAXA/JAMSS 民生コンポーネント活用検討会委員, JAXA/JAMSS 民生コンポーネント活用検討会, Others
  • 01 Sep. 2017 - 28 Feb. 2018
    JAXA/JAMSS 民生コンポーネント活用検討会委員, JAXA/JAMSS 民生コンポーネント活用検討会, Others

Award

  • Oct. 2024
    ADMETA Committee
    Effects of defect clustering on the shape of TDDB lifetime distribution and screening effectiveness
    Best Poster Award, Koichi Endo;Shinji Yokogawa
  • May 2024
    横断型基幹科学技術研究団体連合
    感染症予防難易度の高い社会福祉施設の空気質管理
    木村賞, 横川慎二;石垣陽;喜多村紘子;齋藤彰
  • May 2022
    日本信頼性学会
    機能共鳴分析法を用いた自動車リコール情報の可視化に基づく創発的不具合の構造解析
    高木賞, 横川慎二
    Official journal
  • Jun. 2018
    日本信頼性学会
    テキストマイニングと機能共鳴分析法を用いた自動車リコール情報の分析
    第30回秋期シンポジウム優秀賞, 横川慎二, 國井喬介
    Japan society
  • May 2017
    日本信頼性学会
    リチウムイオン二次電池の劣化における充放電サイクル数と待機時間の影響
    2016春期シンポジウム優秀賞, 横川慎二, 長野祐児
    Japan society
  • 2015
    日本信頼性学会
    原子輸送モデルと応用分布による突出し配線におけるストレス誘起ボイドのレイアウト依存性解析
    2014春期シンポジウム優秀賞, 横川慎二
    Japan society
  • 2014
    IEEE Reliability Society Japan Chapter
    Lifetime Distribution Analysis of Stress-induced Voiding Based on Void Nucleation and Growth in Cu/low-κ Interconnects
    IEEE Reliability Society Japan Chapter Awards 2013, 横川慎二 土屋秀昭
    Japan society
  • 2014
    新版 信頼性ハンドブック(日科技連出版社)
    日経品質管理文献賞, 日本信頼性学会
    Publisher
  • 2012
    Advanced Metallization Conference (ADMETA) Technical Award 2011, Shinji Yokogawa;Hideaki Tsuchiya;Tatsuo Shimizu
    International society
  • 2011
    日本信頼性学会
    HfSiOxによる仕事関数制御MOSトランジスタにおけるランダム・テレグラフ・ノイズ
    2009秋期シンポジウム優秀賞, 清水立雄 加藤一郎 横川慎二
    Japan society
  • 2011
    Role of Impurity Segregation to Cu/Cap Interface and Grain Boundary on Resistivity and Electromigration in Cu/low-k interconnects
    Advanced Metallization Conference (ADMETA) Award 2010, Shinji Yokogawa and Yumi Kakuhara
    International society
  • 2008
    IEEE Reliability Society Japan Chapter
    IEEE Reliability Society Japan Chapter Awards 2007
    Japan society
  • 2007
    財団法人日本電子部品信頼性センター
    インバーターチェーン回路を用いたSoft Breakdown 起因のIDD劣化評価
    第16回電子デバイスの信頼性シンポジウム技術賞, 加藤一郎 横川慎二
    Japan society
  • 2006
    財団法人日本電子部品信頼性センター
    低い累積故障確率におけるエレクトロマイグレーション寿命とボイド形成
    第15回電子デバイスの信頼性シンポジウム優秀論文賞, 土屋秀昭 横川慎二
    Japan society
  • 2004
    日本信頼性学会
    サドンデスTEGとOBIRCHを用いたダマシンCu配線のエレクトロマイグレーション評価
    高木賞, 横川慎二
    Official journal
  • 2001
    財団法人日本電子部品信頼性センター
    多層ダマシンCu配線のエレクトロマイグレーションに関する一考察
    第10回電子デバイスの信頼性シンポジウム優秀論文賞, 横川慎二;岡田紀雄;角原由美;瀧澤秀行
    Japan society
  • 1996
    日本設備管理学会
    劣化量データを用いた設備の最適保全方策とパラメータ推定
    日本設備管理学会論文賞, 横川慎二, 鈴木和幸
    Official journal

Paper

  • 社会福祉施設における感染症予防のための空気質管理
    横川 慎二; 石垣 陽; 喜多村 紘子; 齋藤 彰
    Lead, 横幹, 18, 2, 85-96, Oct. 2024, Peer-reviwed
    Scientific journal, Japanese
  • Assessing personal PM2.5 exposure using a novel neck-mounted monitoring device in rural Rwanda
    Yo Ishigaki; Shinji Yokogawa; Kan Shimazaki; Tin-Tin Win-Shwe; Elisephane Irankunda
    Environmental Monitoring and Assessment, Springer Science and Business Media LLC, 196, 10, 16 Sep. 2024, Peer-reviwed
    Scientific journal, English
  • Monitoring the ventilation of living spaces to assess the risk of airborne transmission of infection using a novel Pocket CO2 Logger to track carbon dioxide concentrations in Tokyo
    Yo Ishigaki; Shinji Yokogawa
    PLOS ONE, Public Library of Science (PLoS), 19, 5, e0303790-e0303790, 23 May 2024, Peer-reviwed, We employed carbon dioxide (CO2) concentration monitoring using mobile devices to identify location-specific risks for airborne infection transmission. We lent a newly developed, portable Pocket CO2 Logger to 10 participants, to be carried at all times, for an average of 8 days. The participants recorded their location at any given time as cinema, gym, hall, home, hospital, other indoors, other outgoings, pub, restaurant, university, store, transportation, or workplace. Generalized linear mixed model was used for statistical analysis, with the objective variable set to the logarithm of CO2 concentration. Analysis was performed by assigning participant identification as the random effect and location as the fixed effect. The data were collected per participant (seven males, four females), resulting in a total of 12,253 records. Statistical analysis identified three relatively poorly ventilated locations (median values > 1,000 ppm) that contributed significantly (p < 0.0001) to CO2 concentrations: homes (1,316 ppm), halls (1,173 ppm), and gyms (1005ppm). In contrast, two locations were identified to contribute significantly (p < 0.0001) to CO2 concentrations but had relatively low average values (<1,000 ppm): workplaces (705 ppm) and stores (620 ppm). The Pocket CO2 Logger can be used to visualize airborne infectious transmission risk by location to help guide recommendation regarding infectious disease policies, such as restrictions on human flow and ventilation measures and guidelines. In the future, large-scale surveys are expected to utilize the global positioning system, Wi-Fi, or Bluetooth of an individual’s smartphone to improve ease and accuracy.
    Scientific journal
  • Evaluation and risk communication of the effects of alcohol exposure on disposable procedure masks and portable air purifiers in hospital environments
    Yo Ishigaki; Shinji Yokogawa; Tatsuo Kato
    Toxicology and Industrial Health, SAGE Publications, 15 Jan. 2024, Peer-reviwed, Electret technology was widely used to prevent the airborne transmission of bioaerosols during the COVID-19 pandemic and improve the filtration efficiency of masks and high-efficiency particulate air (HEPA) filters. As alcohol disinfectants are widely used in medical and welfare institutions, concerns about alcohol exposure inactivating electret exist. However, comprehensive alcohol exposure tests have not been conducted on masks and HEPA filters distributed in Japan. Twenty-five types of masks and five types of HEPA filters were subjected to a discharging process according to ISO 16890 to quantitatively elucidate the resistance to alcohol exposure. Measurements of changes in filtration efficiency and pressure drop before and after discharge show that 17 masks (68%) and four HEPA filters (80%) exhibited a significant decrease in filtration efficiency, confirming their vulnerability to alcohol. In addition, a survey ( n = 500 Japanese adults, including 30 healthcare professionals) revealed that ∼90% of the general public were unaware that alcohol exposure could degrade masks and air purifiers. Furthermore, 36% of the surveyed healthcare professionals had sprayed alcohol directly onto their masks. The effectiveness of user warnings through product labels and instructions was investigated from the perspective of ensuring the safety of patients and healthcare professionals. Results revealed that the best approach was to describe the extent and duration of the adverse effects caused by disregarding precautions. Increase in awareness of healthcare professionals and general public by authorities and manufacturers through guidelines and warning labels would reduce the risk of inhaling bioaerosols caused by unintentional electret inactivation.
    Scientific journal
  • Affinity-Based Power Flow Optimization in Reconfigurable Picogrid
    Ryota Kokubu; Kaito Oeda; Yuusuke Kawakita; Shinji Yokogawa; Yoshito Tobe; Haruhisa Ichikawa
    2024 IEEE/SICE International Symposium on System Integration (SII), IEEE, 08 Jan. 2024
    International conference proceedings
  • Parallelization of DC Feeding Network Setting Time Reduction of Control Frequency
    Kazato Otsu; Haruhisa Ichikawa; Yoshito Tobe; Shinji Yokogawa; Yuusuke Kawakita
    2023 Fourteenth International Conference on Mobile Computing and Ubiquitous Network (ICMU), IEEE, 29 Nov. 2023
    International conference proceedings
  • Ventilatory effects of excessive plastic sheeting on the formation of SARS-Cov-2 in a closed indoor environment
    Yo Ishigaki; Yuto Kawauchi; Shinji Yokogawa; Akira Saito; Hiroko Kitamura; Takashi Moritake
    Corresponding, Environmental and Occupational Health Practice, Japan Society for Occupational Health, 5, 1, n/a-n/a, Jul. 2023, Peer-reviwed
    Scientific journal, English
  • Statistical modeling of V th distribution in ovonic threshold switches based on physical switching models
    Shinji Yokogawa
    Lead, Japanese Journal of Applied Physics, IOP Publishing, 62, SH, SH1001-SH1001, 15 Feb. 2023, Peer-reviwed, Abstract

    This paper discusses the statistical modeling of the Vth distribution of an ovonic threshold switch, an integral component of high-speed, high-capacity storage-class memory. A distribution function that explains the Vth variation and a method for estimating and judging it is proposed based on three representative switching mechanisms—thermal runaway model, physically based electrical model, and two-state defect model. We examined the relationship between the segment Vth distribution and Vth minimum distribution is examined by considering chip-level scaling in Monte Carlo simulations and analytical analysis of the distribution function. The latter distribution approaches the Weibull distribution; however, its convergence speed differs.
    Scientific journal
  • Estimation of air change rate by CO2 sensor network in workplace with COVID-19 outbreak
    Shinji Yokogawa; Yo Ishigaki; Hiroko Kitamura; Akira Saito; Yuto Kawauchi; Taisei Hiraide
    Lead, Environmental and Occupational Health Practice, Japan Society for Occupational Health, 2023, Peer-reviwed
    Scientific journal
  • Pilot Evaluation of Possible Airborne Transmission in a Geriatric Care Facility Using Carbon Dioxide Tracer Gas: Case Study
    Yo Ishigaki; Shinji Yokogawa; Yuki Minamoto; Akira Saito; Hiroko Kitamura; Yuto Kawauchi
    JMIR Formative Research, JMIR Publications Inc., 6, 12, e37587-e37587, 30 Dec. 2022, Peer-reviwed, Background

    Although several COVID-19 outbreaks have occurred in older adult care facilities throughout Japan, no field studies focusing on airborne infections within these settings have been reported. Countermeasures against airborne infection not only consider the air change rate (ACR) in a room but also the airflow in and between rooms. However, a specific method has not yet been established by Japanese public health centers or infectious disease–related organizations.

    Objective

    In April 2021, 59 COVID-19 cases were reported in an older adult care facility in Miyagi, Japan, and airborne transmission was suspected. The objective of this study was to simultaneously reproduce the ACR and aerosol advection in this facility using the carbon dioxide (CO2) tracer gas method to elucidate the specific location and cause of the outbreak. These findings will guide our recommendations to the facility to prevent recurrence.

    Methods

    In August 2021, CO2 sensors were placed in 5 rooms where airborne infection was suspected, and the CO2 concentration was intentionally increased using dry ice, which was subsequently removed. The ACR was then estimated by applying the Seidel equation to the time-series changes in the CO2 concentration due to ventilation. By installing multiple sensors outside the room, advection outside the room was monitored simultaneously. Aerosol advection was verified using computer simulations. Although the windows were closed at the time of the outbreak, we conducted experiments under open-window conditions to quantify the effects of window opening.

    Results

    The ACR values at the time of the outbreak were estimated to be 2.0 to 6.8 h−1 in the rooms of the facility. A low-cost intervention of opening windows improved the ventilation frequency by a factor of 2.2 to 5.7. Ventilation depended significantly on the window-opening conditions (P values ranging from .001 to .03 for all rooms). Aerosol advection was detected from the private room to the day room in agreement with the simulation results. Considering that the individual who initiated the infection was in the private room on the day of infection, and several residents, who later became secondarily infected, were gathered in the day room, it was postulated that the infectious aerosol was transmitted by this air current.

    Conclusions

    The present results suggest that secondary infections can occur owing to aerosol advection driven by large-scale flow, even when the building design adheres to the ventilation guidelines established in Japan. Moreover, the CO2 tracer gas method facilitates the visualization of areas at a high risk of airborne infection and demonstrates the effectiveness of window opening, which contributes to improved facility operations and recurrence prevention.
    Scientific journal
  • CO2センサを活用した循環器健診車内の換気可視化の検討
    齋藤彰; 石垣陽; 横川慎二; 川内雄登; 田中晴美; 浅野美穂; 小川美紀; 石川正悟; 高橋里美; 齋藤泰紀
    日本人間ドック学会誌, 37, 4, 699-707, Dec. 2022, Peer-reviwed
  • Ventilation improvement and evaluation of its effectiveness in a Japanese manufacturing factory
    Hiroko Kitamura; Yo Ishigaki; Hideaki Ohashi; ShinjiYokogawa
    scientific reports, nature.com, 12, 1, 17642-17642, 21 Oct. 2022, Peer-reviwed, True, A coronavirus disease 2019 (COVID-19) cluster emerged in a manufacturing factory in early August 2021. In November 2021, we conducted a ventilation survey using the tracer gas method. Firstly, we reproduce the situation at the time of cluster emergence and examined whether the ventilation in the office was in a condition that increased the risk of aerosol transmission. Secondly, we verified the effectiveness of the factory's own countermeasure implemented immediately after the August cluster outbreak. Furthermore, we verified the effectiveness of several additional improvement measures on the factory's own countermeasures already installed in August. Under the conditions of the cluster emergence, the air changes per hour (ACH) value was 0.73 ACH on average. The ACH value was less than 2 ACH recommended by the Ministry of Health, Labour, and Welfare, suggesting an increased risk of aerosol transmission. The factory's own countermeasures taken immediately in August were found to be effective, as the ACH value increased to 3.41 ACH on average. Moreover, it was confirmed that additional improvement measures on the factory's own countermeasures increased the ACH value to 8.33 ACH on average. In order to prevent the re-emergence of COVID-19 clusters due to aerosol infection in the office, it was found that while continuing the factory's own countermeasure, additional improvement measures should also be added depending on the number of workers in the room. In a company, it is important that workers themselves continue to take infection control measures autonomously, and confirming the effectiveness of the measures will help maintain workers' motivation. We believe it is helpful that external researchers in multiple fields and internal personnel in charge of the health and safety department and occupational health work together to confirm the effectiveness of conducted measures, such as in this case.
    Scientific journal, English
  • Indirect diagnosis methods of energy storage capability for mobile devices with USB power delivery
    Minoru Asano; Shinji Yokogawa; Haruhisa Ichikawa
    IEICE Communications Express, 11, 7, 455-460, 10 May 2022, Peer-reviwed
    English
  • A method for generating graphs to derive maximum flow and its evaluation
    Takumi Wada; Haruhisa Ichikawa; Shinji Yokogawa; Yoshito Tobe; Yuusuke Kawakita
    IEICE Communications Express, 11, 8, 468-473, 04 Feb. 2022, Peer-reviwed
    English
  • Analysis of the Trends Between Indoor Carbon Dioxide Concentration and Plug-Level Electricity Usage Through Topological Data Analysis
    Shun Endo; Shinji Yokogawa
    IEEE Sensors Journal, 22, 2, 1424-1434, 15 Jan. 2022, Peer-reviwed
    Scientific journal, English
  • ユーザーの利用調査データに基づくモバイル端末のバッテリー劣化量分析
    浅野 実; 横川 慎二; 石垣 陽; 冨永 潤一; 粟津 浜一
    モバイル学会誌, 11, 1・2, 1-8, 31 Dec. 2021, Peer-reviwed
    Scientific journal, Japanese
  • 位相的データ解析を用いた室内環境に関する時系列多次元データの分析
    遠藤駿; 横川慎二
    電子情報通信学会・システムソサイエティ和文論文誌, 電子情報通信学会, 104-D, 4, 318-327, 01 Apr. 2021, Peer-reviwed
    Scientific journal, Japanese
  • Toward efficient power delivery using USB power delivery hub: Poster abstract
    K. Takaie; K. Tamura; Y. Kawakita; S. Yokogawa; Y. Tobe; H. Ichikawa
    SenSys 2020 - Proceedings of the 2020 18th ACM Conference on Embedded Networked Sensor Systems, Association for Computing Machinery, Inc, 733-734, 16 Nov. 2020, Power delivery (PD) to computing and sensing devices in an indoor environment is as important as data communication between them. We are developing a USB-PD-based DC power supply system called VGHub. As the power loss at each input and output port of VGHub depends on the incoming or outgoing power at the port, the power distribution among all the ports needs to be optimized to maximize the power efficiency of VGHub. In this poster paper, we describe the formulation of a power distribution control in VGHub.
    International conference proceedings, English
  • エゾシカ肉のおいしさのリアルタイム計測
    武山真弓; 佐藤勝; 安井崇; 横川慎二
    電子情報通信学会論文誌 C, J103-C, 9, 387-394, 19 Aug. 2020, Peer-reviwed, Invited
    Scientific journal, Japanese
  • Humidity reliability of commercial flash memories for long-term storage
    Tomoki Murota; Toshiki Mimura; Ploybussara Gomasang; Shinji Yokogawa; Kazuyoshi Ueno
    Japanese Journal of Applied Physics, IOP PUBLISHING LTD, 59, SL, SLLC01-1-SLLC01-4, 23 Apr. 2020, Peer-reviwed, To investigate the feasibility of flash memory reliability in an environment for the application of long-term data storage, temperature and humidity acceleration tests have been carried out for commercial flash memories. Nine commercial 16GB SD cards with conventional package were kept in a test chamber of 85 degrees C/85%RH for up to 3040 h and we checked the write/read operation using free software "Check Flash" after the storage test. The lifetime against humidity is predicted by the power law humidity model (Peck model), which is widely used for the lifetime prediction, assuming the average parameters such as humidity acceleration factor (n) and activation energy (E-a) from the literatures. Although further studies to assure the reliability, the results indicate that commercial flash memories preliminary have the feasibility of a long-term storage media over 100 years. (C) 2020 The Japan Society of Applied Physics
    Scientific journal, English
  • Applications of lifetime distribution functions with two shape parameters for reliability analysis in advanced interconnect technologies: a brief review
    Shinji Yokogawa
    Japanese Journal of Applied Physics, 59, SL, SL0802-1-SL0802-13, 01 Apr. 2020, Peer-reviwed, Invited
    Scientific journal, English
  • Seven View Points and Reliability Engineering Scheme for Preventing Reliability Problems
    Kazuyuki Suzuki; Shinji Yokogawa
    International Journal of Reliability, Quality and Safety Engineering, World Scientific, 26, 6, 2050006-1-2050006-17, 13 Sep. 2019, Peer-reviwed
    Scientific journal, English
  • Liner- and barrier-free NiAl metallization: A perspective from TDDB reliability and interface status
    Linghan Chen; Daisuke Ando; Yuji Sutou; Shinji Yokogawa; Junichi Koike
    Applied Surface Science, Elsevier, 497, 15, 143810-1-143810-5, 27 Aug. 2019, Peer-reviwed, This study reports the time-dependent-dielectric-breakdown (TDDB) reliability of NiAl on SiO without any barrier layer. NiAl was indicated to exhibit superior TDDB reliability in comparison to Cu/TaN in the time-to-failure (4200 s versus 240 s, at 4 MV/cm at 200 °C) and in the breakdown activation energy under 4 MV/cm (1.17 eV versus 0.87 eV). Moreover, NiAl was found to form an atomically thin and self-limiting Al oxide layer at the NiAl/SiO interface, and this Al oxide layer, together with the large cohesive energy of NiAl, was considered to be possible origin for the excellent reliability. The results demonstrate a great potential of NiAl as a liner- and barrier-free interconnect material. 2 2
    Scientific journal, English
  • Bayesian inference of a lifetime distribution parameter on the time-dependent dielectric breakdown with clustering defects
    Kyosuke Kunii; Shun Endo; Shinji Yokogawa
    Japanese Journal of Applied Physics, 58, SH, SHHG02-1-SHHG02-8, 05 Jul. 2019, Peer-reviwed
    Scientific journal, English
  • グラフ列挙による風力・太陽光・蓄電池複合システムの重複グルーピング最適化
    武田健吾; 澤田 賢治; 横川 慎二; 新誠一
    電気学会論文誌C, 139, 7, 786-795, 01 Jul. 2019, Peer-reviwed
    Scientific journal, Japanese
  • 機能共鳴分析法を用いた自動車リコール情報の可視化に基づく創発的不具合の構造解析
    横川慎二
    日本信頼性学会誌, 日本信頼性学会, 41, 135-147, 01 Mar. 2019, Peer-reviwed
    Scientific journal, Japanese
  • Lifetime prediction model of Cu-based metallization against moisture under temperature and humidity accelerations
    Ploybussara Gomasang; Satoru Ogiue; Shinji Yokogawa; Kazuyoshi Ueno
    Japanese Journal of Applied Physics, 58, SB, SBBC01-1-SBBC01-6, 22 Feb. 2019, Peer-reviwed, To establish the lifetime prediction model for Cu-based metallization against moisture, temperature humidity storage test under the various accelerated conditions is performed. The increase of Cu sheet resistance induced by Cu-oxidation is measured by a four-point probe method. X-ray photoelectron spectroscopy analysis is carried out to investigate the variation of oxidized Cu. The activation energy and the humidity acceleration factor for Cu-based metallization have been derived by the statistical analysis to predict the lifetime against moisture for the first time. The results indicate that Cu-based metallization is comparatively more sensitive to the temperature than humidity at around the practical use condition.
    Scientific journal, English
  • Overlapped grouping optimization for wind-photovoltaic-battery hybrid system by graph enumeration
    Kengo Takeda; Kenji Sawada; Shinji Yokogawa; Seiichi Shin
    IEEJ Transactions on Electronics, Information and Systems, Institute of Electrical Engineers of Japan, 139, 7, 786-795, 2019, In a system that suppresses power fluctuation caused by wind power and solar power generation by a storage battery (We call it wind turbine and photovoltaic power generation system, WPBHS), it is assumed that the number of constituent equipment is large. Therefore, by dividing the constituent equipment into a plurality of groups (We call it grouping), the operation plan is optimized dispersedly. In this case, it has been shown that WPBHS has fault tolerance by overlapping storage batteries in plural groups. Also, enumerating the grouping in advance allows us to switch the grouping and recover the system immediately when a system failure occurs. Motivated by this, we consider an overlapped grouping optimization problem focused on the performance deterioration and fault tolerance of the distributed management system. Enumerating the group, especially, the overlapped group requires large computational load with the more devices added. First, this paper formulates overlapped grouping optimization for WPBHS. Second, this paper proposes a graph representation method of the overlapped grouping and a near-optimal enumeration method.
    Scientific journal, Japanese
  • 風力・太陽光・蓄電池複合システムの重複分散運用の検討
    武田健吾; 澤田 賢治; 横川 慎二; 新誠一
    電気学会論文誌C, 138, 12, 1554-1565, 01 Dec. 2018, Peer-reviwed
    Scientific journal, Japanese
  • A survey of critical failure events in on-chip interconnect by using fault tree analysis
    S. Yokogawa; K. Kunii
    Japanese Journal of Applied Physics, 57, 7S2, 21 May 2018, Peer-reviwed
    Scientific journal, English
  • A statistical evaluation method for lifetime distribution in field accelerated time-dependent dielectric breakdwon by using two-step probability plot and multi-link test scheme
    K. Tate; S. Yokogawa
    Japanese Journal of Applied Physics, 57, 7S2, 21 May 2018, Peer-reviwed
    Scientific journal, English
  • On the overlapping decentralized operation for wind-photovoltaic-battery hybrid system
    Kengo Takeda; Kenji Sawada; Shinji Yokogawa; Seiichi Shin
    IEEJ Transactions on Electronics, Information and Systems, Institute of Electrical Engineers of Japan, 138, 12, 1554-1565, 2018, Wind and solar power generators cause electric power fluctuation, batteries are combined with such the renewable energy system to absorb power fluctuations, so called, wind turbine and photovoltaic power generators and battery hybrid system (WPBHS). Such the system mainly focuses on the decentralized operation in which a large number of system devices are managed decentrally. On the other hand, its stable generating capability and fault tolerance performance depends on how to group devices into small groups in which components are managed centrally (We call it grouping). That is, the grouping itself can improve the decentralized operation performance. This paper considers overlapping grouping of WPBHS in which one device belongs to multiple groups and proposes a new decentralized operation. To verify the validity of the proposed method, this paper shows numerical experiments in terms of stable generation and fault tolerance.
    Scientific journal, Japanese
  • Two-step probability plot for parameter estimation of lifetime distribution affected by defect clustering in time-dependent dielectric breakdown
    Shinji Yokogawa
    JAPANESE JOURNAL OF APPLIED PHYSICS, IOP PUBLISHING LTD, 56, 7, Jul. 2017, Peer-reviwed, In this study, a simple method of statistical parameter estimation is proposed for lifetime distribution that has three parameters due to the defect clustering in the middle-of-line and back-end-of-line. A two-step procedure provides the estimations of distribution parameters effectively for the time-dependent dielectric breakdown. In the first step, a clustering parameter of distribution, which is one of the shape parameters, is estimated by a linearization treatment of plotted data on the proposed chart. Then, in the second step, shape and scale parameters are estimated by calculating of a slope and an intercept, respectively. The statistical accuracy of the estimates is evaluated using the Monte-Carlo simulation technique and mean squared error of estimates. (C) 2017 The Japan Society of Applied Physics
    Scientific journal, English
  • トラブル予測表を用いた故障モード予測方法と信頼性・安全性の作りこみ評価指標の提案
    山﨑雄大; 横川慎二; 鈴木和幸
    日本信頼性学会誌, 日本信頼性学会, 38, 4, 271-283, Jul. 2016, Peer-reviwed
    Scientific journal, Japanese
  • Simulation study for lifetime distribution of middle-of-line time-dependent dielectric breakdown affected by global and local spacing variations
    Shinji Yokogawa
    JAPANESE JOURNAL OF APPLIED PHYSICS, IOP PUBLISHING LTD, 55, 6, 06JF02-1-06JF02-6, Jun. 2016, Peer-reviwed, The impact of process fluctuations for the lifetime distribution of middle-of-line time-dependent dielectric breakdown was investigated by Monte-Carlo simulation. Global and local variations were simulated using a doubly truncated normal distribution. A goodness of fit to the generated data was determined statistically in terms of the Weibull distribution and clustering model. A change in the standard deviation of the global variation shows a large contribution to lifetime variation. However, it does not affect the average lifetime. A change in the standard deviation of the local variation contributes to both the average lifetime and the distribution variation. The upper limit of the process variation induces the convex upward shape of the lifetime distribution on the Weibull plot. The clustering model well explains the distribution shape. (C) 2016 The Japan Society of Applied Physics
    Scientific journal, English
  • Statistical characteristics of lifetime distribution based on defect clustering for time-dependent dielectric breakdown in middle-and back-end-of-line
    Shinji Yokogawa
    JAPANESE JOURNAL OF APPLIED PHYSICS, IOP PUBLISHING LTD, 54, 5, May 2015, Peer-reviwed, The statistical characteristics of the lifetime distribution based on defect clustering were investigated for middle- and back-end-of-line time-dependent dielectric breakdown. The statistical precision of lifetime estimation was investigated. The maximum likelihood estimators of distribution parameters and their variations were developed by using asymptotic theory. The calculated asymptotic variation coefficient indicates that larger numbers of data are required to maintain the statistical precision of lifetime estimation for highly clustering conditions. However, the censoring of the test time to eliminate the tail of the lifetime distribution has a low impact on the asymptotic variation coefficient of the lifetime. These results provide valuable information for the experimental design of lifetime testing. (C) 2015 The Japan Society of Applied Physics
    Scientific journal, English
  • Lifetime prediction model of stress-induced voiding in Cu/low-kappa interconnects
    Shinji Yokogawa
    JAPANESE JOURNAL OF APPLIED PHYSICS, IOP PUBLISHING LTD, 53, 5, 216-221, May 2014, Peer-reviwed, A lifetime prediction model of stress-induced voiding (SIV) has been developed to investigate the geometry dependence of lifetime in Cu/low-kappa interconnects. A physical extrapolation model based on Cu ionic transport and time-dependent stress relaxation is proposed for obtaining an accurate estimation. The validity of the model is discussed from the viewpoints of linewidth and temperature dependences by comparison with an extrapolation using the empirical power law. (C) 2014 The Japan Society of Applied Physics
    Scientific journal, English
  • Highly reliable molecular-pore-stacking (MPS)/Cu interconnects featuring best combination of post-etching treatment and resputtering processes
    Daisuke Oshida; Ippei Kume; Hirokazu Katsuyama; Makoto Ueki; Manabu Iguchi; Shinji Yokogawa; Naoya Inoue; Noriaki Oda; Michio Sakurai
    MICROELECTRONIC ENGINEERING, ELSEVIER SCIENCE BV, 118, 72-78, Apr. 2014, Peer-reviwed, Effects of post-etching treatment (PET) in trench patterning and resputtering in barrier metal sputtering on low-k/Cu interconnects were investigated for the low-k of molecular pore stacking (MPS). Optimized combination of PET and resputtering reduces wiring capacitance by 5% due to well controlled profile, resulted from hardening effect of the exposed MPS at the trench bottom. The developed process sequence achieves 10 times longer EM lifetime and eliminates early failure mode in the TDDB test. Thus, the novel process, featuring PET and resputtering, contributes to high reliability for 28 nm node CMOS and beyond. (C) 2014 Elsevier B.V. All rights reserved.
    Scientific journal, English
  • Moisture absorption impact on Cu alloy/low-k reliability during process queue time
    H. Tsuchiya; S. Yokogawa; H. Kunishima; T. Kuwajima; T. Usami; Y. Miura; K. Ohto; K. Fujii; M. Sakurai
    MICROELECTRONIC ENGINEERING, ELSEVIER SCIENCE BV, 106, 205-209, Jun. 2013, Peer-reviwed, The moisture absorption impacts on electromigration (EM) and time dependent dielectric breakdown (TDDB) were investigated in Cu/low-k interconnects that is adopting CuAl alloy seed technique. A long queue time (Q-time) has a serious impact on kinetics of both EM and TDDB characteristics. The moisture absorption causes the loss of alloy effects on EM lifetime improvements. The ultra-thin SiN (UT-SiN) remarkably suppresses the moisture absorption impacts due to Q-time. It also inhibits kinetics degradations of EM and TDDB that depend on the moisture absorption to low-k. (C) 2013 Elsevier B.V. All rights reserved.
    Scientific journal, English
  • Highly reliable enhanced nitride interface process of barrier low-k using ultra-thin SiN with moisture blocking capability
    Tatsuya Usami; Yukio Miura; Tomoyuki Nakamura; Hideaki Tsuchiya; Chikako Kobayashi; Koichi Ohto; Shoichi Hiroshima; Mikio Tanaka; Hiroyuki Kunishima; Issei Ishizuka; Teruhiro Kuwajima; Michio Sakurai; Shinji Yokogawa; Kunihiro Fujii
    Microelectronic Engineering, 112, 97-102, 2013, Peer-reviwed, We developed a highly reliable enhanced nitride Interface (ENI) process of barrier low-k using an ultra-thin SiN (UT-SiN) for 40-nm node devices and beyond. The UT-SiN (3 nm) exhibits stable thickness uniformity and an excellent moisture blocking capability. By using this process, a lower effective k and high via yields were obtained. Compared to the conventional SiCN bi-layer process, 5× via electro-migration improvement, 50× time dependent dielectric breakdown improvement and no stress induced voiding failure within 1000 h were observed. The ENI process was analyzed using X-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry. From these analyses, we propose the mechanism for these reliability performance improvements. © 2013 Elsevier B.V. All rights reserved.
    Scientific journal, English
  • Thermal Transient Response and Its Modeling for Joule Heating in Cu/Low-kappa Interconnects Under Pulsed Current
    Shinji Yokogawa; Hideaki Tsuchiya; Tatsuo Shimizu
    JAPANESE JOURNAL OF APPLIED PHYSICS, JAPAN SOC APPLIED PHYSICS, 51, 5, 350-357, May 2012, Peer-reviwed, We propose a thermal transient response due to Joule heating and its modeling in Cu/low-kappa interconnects. By incorporating a shape parameter on the model, the observed thermal response is more accurately represented compared to the conventional exponential function model. The effective thermal time constant in multilayered Cu/low-kappa interconnects is experimentally investigated on the basis of the transient thermal response. (C) 2012 The Japan Society of Applied Physics
    Scientific journal, English
  • Role of Impurity Segregation into Cu/Cap Interface and Grain Boundary in Resistivity and Electromigration of Cu/Low-k Interconnects
    Shinji Yokogawa; Yumi Kakuhara
    JAPANESE JOURNAL OF APPLIED PHYSICS, JAPAN SOC APPLIED PHYSICS, 50, 5, May 2011, Peer-reviwed, The role of impurity segregation into the Cu/cap interface and grain boundary is discussed in terms of resistivity and electromigration (EM) lifetime. A Co-based metal capping, a CuAl seed, and new liners (Ti, Zr, and Hf) are compared as technologies for EM lifetime improvement. The roles of impurity in grain growth and electron scattering are investigated by residual resistivity measurement and physical analysis. The EM lifetime distribution and activation energy of lifetime are also investigated. The efficiency of EM improvements is discussed in terms of the trade-off characteristics of each technology during use. The EM improvement efficiency is categorized into three groups. (C) 2011 The Japan Society of Applied Physics
    Scientific journal, English
  • Highly reliable molecular-pore-stacking (MPS)/Cu interconnects using novel post-etching treatment (PET) for 28 nm-node and beyond
    D. Oshida; I. Kume; H. Kunishima; H. Tsuchiya; H. Katsuyama; M. Ueki; M. Iguchi; S. Yokogawa; N. Inoue; N. Oda; M. Sakurai
    2011 IEEE International Interconnect Technology Conference and 2011 Materials for Advanced Metallization, IITC/MAM 2011, 2011, Effects of post-etching treatment (PET) in trench patterning and re-sputtering in barrier metal sputtering on low-k/Cu interconnects were investigated for the low-k of Molecular Pore Stacking (MPS). Optimized combination of PET and re-sputtering reduces wiring capacitance by 5% due to well controlled profile, resulted from hardening effect of the exposed MPS at the trench bottom. The developed process sequence achieves 10 times loger EM lifetime and eliminates early failure mode in the TDDB test. Thus, the novel process, featuring PET and re-sputtering, contributes to highly reliability for 28 nm node CMOS and beyond. © 2011 IEEE.
    International conference proceedings, English
  • Failure analysis of fine Cu patterning by shave-off profiling
    M. Nojima; M. Fujii; Y. Kakuhara; H. Tsuchiya; A. Kameyama; S. Yokogawa; M. Owari; Y. Nihei
    SURFACE AND INTERFACE ANALYSIS, WILEY-BLACKWELL, 43, 1-2, 621-624, Jan. 2011, Peer-reviwed, We focused on failure within fine copper patterning on a semiconductor chip. Three grades of samples were prepared; hard CMP treatment, soft CMP treatment and standard, and compared the differences by shave-off profiling. The shave-off profiles of CMP treatment revealed a saw-toothed structure, and the shave-off profile of a standard chip was revealed as a periodic triangular wave. The difference can be explained by the existence of residue on the CMP process. Copyright (C) 2010 John Wiley & Sons, Ltd.
    Scientific journal, English
  • Statistical Analysis of Lifetime Distribution of Time-Dependent Dielectric Breakdown in Cu/Low-k Interconnects by Incorporation of Overlay Error Model
    Shinji Yokogawa; Hideaki Tsuchiya
    JAPANESE JOURNAL OF APPLIED PHYSICS, JAPAN SOC APPLIED PHYSICS, 49, 5, May 2010, Peer-reviwed, We propose a method for the statistical analysis of a via-to-line time-dependent dielectric breakdown (TDDB) test under misalignment impacts. The root E and overlay error models are incorporated into the lifetime distribution analysis in the framework of the Weibull regression model. The doubly truncated normal distribution effectively describes the space-decrease distribution that is estimated using the overlay error model. Incorporating these physical and statistical characteristics into the lifetime distribution analysis yields more reliable distribution parameters and helps to distinguish outliers as early failures with rejection of misalignment impacts. (C) 2010 The Japan Society of Applied Physics
    Scientific journal, English
  • Role of impurity segregation to Cu/Cap interface and grain boundary on resistivity and electromigration in Cu/low-k interconnects
    Shinji Yokogawa; Y. Kakuhara
    Lead, Advanced Metallization Conference (AMC), 101-102, 2010, Invited, Supplied impurities in EM boosters affect to grain growth in narrow Cu lines, and resistivity of the line well depends on the electron scattering at the grain boundaries. The EM improvement efficiency of Ti liner is similar with CuAl seed because of small contribution of the grain boundary diffusion and the adhesion improvement at the Cu/liner interface.
    International conference proceedings, English
  • Comparison of Lifetime Improvements in Electromigration between Ti Barrier Metal and Chemical Vapor Deposition Co Capping
    Yumi Kakuhara; Shinji Yokogawa; Kazuyoshi Ueno
    JAPANESE JOURNAL OF APPLIED PHYSICS, JAPAN SOC APPLIED PHYSICS, 49, 4, 2010, Peer-reviwed, As promising technologies for fabrication of highly reliable Cu interconnects, using Ti barrier metal (Cu/Ti) and chemical vapor deposition (CVD) Co capping (Co/Cu/Ta/TaN) were compared. Both Cu interconnects similarly showed longer electromigration (EM) lifetime and larger activation energy of lifetime than conventional Cu interconnects fabricated using Ta/TaN barrier metal without capping metal (Cu/Ta/TaN). The residual resistance of Cu lines was measured cryogenically. Cu/Ti showed a higher residual resistance than Co/Cu/Ta/TaN and Cu/Ta/TaN, which indicates the presence of more impurities and a higher density of grain boundaries in Cu/Ti. Energy dispersive X-ray spectroscopy (EDX) analysis showed that a large amount of Ti doped into the Cu line segregated mostly at the grain boundaries on the Cu surface. It is suggested that Ti doped into a Cu line suppresses Cu diffusion through only the grain boundaries on the Cu surface. On the other hand, Co capping suppresses Cu diffusion through the entire Cu surface. As Cu/Ti improved EM lifetime significantly, the grain boundaries on the Cu surface are proposed to be a predominant diffusion path in EM. Since the density of grain boundaries probably increases on the Cu surface as interconnects shrink, suppressing the grain boundary diffusion on the Cu surface is highly effective to strengthen EM reliability. (C) 2010 The Japan Society of Applied Physics
    Scientific journal, English
  • Suppression of Electromigration Early Failure of Cu/Porous Low-k Interconnects Using Dummy Metal
    Yumi Kakuhara; Shinji Yokogawa; Masayuki Hiroi; Toshiyuki Takewaki; Kazuyoshi Ueno
    JAPANESE JOURNAL OF APPLIED PHYSICS, JAPAN SOC APPLIED PHYSICS, 48, 9, Sep. 2009, Peer-reviwed, The electromigration (EM) lifetime of Cu/porous low-k interconnects was evaluated by EM experiments in which the effect of back-flow stress was negligible. The EM lifetime of the downstream mode was reduced using a porous low-k film (SiOCH) as an intermetal dielectric (IMD) in comparison with using a SiO2 dielectric. The reduction in EM lifetime was observed only at low cumulative failure probability, considered as "early failure". The early failure was caused by the formation of a slit void under a via. It was found that the early failure was suppressed by placing a dummy metal near the metal/via contact that inhibited the formation of a slit void. The EM degradation of Cu/porous low-k interconnects is likely to be caused by the mechanical properties of porous low-k film. The dummy metal supports the porous low-k film near the metal/via contact, which leads to improved EM. (C) 2009 The Japan Society of Applied Physics
    Scientific journal, English
  • Photo misalignment impacts on the low-k TDDB
    H. Tsuchiya; Y. Kakuhara; D. Oshida; M. Iguchi; T. Takewaki; S. Yokogawa
    Advanced Metallization Conference (AMC), 719-725, 2009, We have investigated the characteristics of the time dependent dielectric breakdown (TDDB) on Cu/low-k interconnects with vias. The photo misalignment impacts on lifetime were demonstrated experimentally by using 90 nm and 55 nm technology node. The local field enhancement, caused by the electric field focusing at the edge of vias, could be negligible. So, the lifetime can be simply predicted by actual via-to-line electric field. It was found that the fluctuation of space makes the shape parameter small and it causes pessimistic lifetime prediction. We therefore propose the reduction of space fluctuation influence with the overlay error model. It allows more accurate lifetime prediction. © 2009 Materials Research Society.
    International conference proceedings, English
  • Analysis of Al doping effects on resistivity and electromigration of copper interconnects
    Shinji Yokogawa; Hideaki Tsuchiya; Yumi Kakuhara; Kuniko Kikuta
    IEEE TRANSACTIONS ON DEVICE AND MATERIALS RELIABILITY, IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 8, 1, 216-221, Mar. 2008, Peer-reviwed, In this paper, we investigated the effect of impurity (aluminum; Al) doping on the resistivity of damascene copper (Cu) interconnects by categorizing it into surface, grain-boundary, and impurity-scattering factors by means of a comprehensive scattering model. Segregation of Al dopant atoms to the interface of the lines increases the resistivity through increased surface scattering. Electromigration (EM)-induced Cu drift is suppressed as the Al concentration increases. The EM lifetime is improved by the suppression of Cu diffusion due to the piled-up Al at the top surface of the Cu interconnects.
    Scientific journal, English
  • Quantitative analysis of correlation between insulator surface copper contamination and TDDB lifetime based on actual measurement
    D. Oshida; T. Takewaki; M. Iguchi; T. Taiji; T. Morita; Y. Tsuchiya; H. Tsuchiya; S. Yokogawa; H. Kunishima; H. Aizawa; N. Okada
    2008 IEEE International Interconnect Technology Conference, IITC, 222-224, 2008, We have analyzed the correlation between insulator surface copper contamination and time-dependent dielectric breakdown (TDDB) quantitatively for the first time. TDDB lifetime strongly depends on the copper contamination after CMP process, and it is important to control the redox potential to be less than -0.5 V vs. NHE and to utilize a chelating agent on cleaning sequence. Furthermore, we have successfully optimized the post-CMP sequence to decrease the size of antioxidant-copper complex, and improved the TDDB lifetime. ©2008 IEEE.
    International conference proceedings, English
  • Tradeoff characteristics between resistivity and reliability for scaled-down Cu-based interconnects
    Shinji Yokogawa; Kuniko Kikuta; Hideaki Tsuchiya; Toshiyuki Takewaki; Mieko Suzuki; Hironori Toyoshima; Yumi Kakuhara; Naoyoshi Kawahara; Tatsuya Usami; Koichi Ohto; Kunihiro Fujii; Yasuaki Tsuchiya; Koji Arita; Koichi Motoyama; Makoto Tohara; Toshiji Taiji; Tetsuya Kurokawa; Makoto Sekine
    IEEE TRANSACTIONS ON ELECTRON DEVICES, IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC, 55, 1, 350-357, Jan. 2008, Peer-reviwed, We investigated tradeoff characteristics between resistivity and reliability for scaled-down Cu-based interconnects. A unique resistivity-measurement technique is proposed to detect influences due to impurity doping. Using this technique, we investigated the impacts of the impurity doping on three types of copper interconnects-cobalt-tungsten-phosphorous (CoWP) metal-cap interconnects, plasma-enhanced chemical-vapor-deposition self-aligned barrier interconnects, and CuAl alloy interconnects-and clarified the tradeoffs between the resistivity and the reliability. We found that the metal-cap interconnect shows not only high reliability but also outstanding efficiency with regard to the suppression of resistance increase due to impurity doping.
    Scientific journal, English
  • A robust embedded ladder-oxide/Cu multilevel interconnect technology for 0.13 mu m complementary metal oxide semiconductor generation
    Noriaki Oda; Shinya Ito; Toshiyuki Takewaki; Kazutoshi Shiba; Hiroyuki Kunishima; Nobuo Hironaga; Ichiro Honma; Hiroaki Nanba; Shinji Yokogawa; Akiko Kameyama; Takayuki Goto; Tatsuya Usami; Koichi Ohto; Akira Kubo; Mieko Suzuki; Yoshiaki Yamamoto; Susumu Watanabe; Kenta Yamada; Masahiro Ikeda; Kazuyoshi Ueno; Tadahiko Horiuchi
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS BRIEF COMMUNICATIONS & REVIEW PAPERS, INST PURE APPLIED PHYSICS, 46, 3A, 954-961, Mar. 2007, Peer-reviwed, A robust embedded ladder-oxide (k = 2.9)/copper (Cu) multilevel interconnect is demonstrated for 0.13 mu m complementary metal oxide semiconductor (CMOS) generation. A stable ladder-oxide intermetal dielectric (IMD) is integrated by the Cu metallization with a minimum wiring pitch of 0.34 mu m, and a single damascene (S/D) Cu-plug structure is applied. An 18% reduction in wiring capacitance is obtained compared with that in SiO2 IMDs. The superior controllability of metal thickness by the S/D process enables us to enhance the MPU maximum frequency easily. The stress-migration lifetime of vias on wide metals for the S/D Cu-plug structure is longer than that for a dual damascene (D/D) structure. Reliability test results such as electromigration (EM), the temperature dependant dielectric breakdown (TDDB) of Cu interconnects, and pressure cooker test (PCT) results are acceptable. Moreover, a high flexibility in a thermal design is obtained.
    Scientific journal, English
  • Effects of Al doping on the electromigration performance of damascene Cu interconnects
    Shinji Yokogawa; Hideaki Tsuchiya
    JOURNAL OF APPLIED PHYSICS, AMER INST PHYSICS, 101, 1, Jan. 2007, Peer-reviwed, We report the effects of Al doping on electromigration in damascene Cu interconnects. Al doping was performed by thermal diffusion from a CuAl seed layer positioned underneath the Cu interconnects. To investigate the dependencies of the Al concentration, the seed CuAl layer thickness was increased from 40 to 90 nm on a planar surface. The effects of Al doping on the incubation time, drift velocity, and critical product of electromigration were investigated. The drift velocity of Cu mass transport in CuAl alloys decreases with an increase in the concentration of Al atoms. The observed critical product of electromigration is 1500 A/cm, and it is independent of the Al concentration. The measured activation energies of the normalized drift velocities for CuAl seed layer thicknesses of 40, 60, and 90 nm are 1.2, 1.4, and 1.5 eV, respectively. The Al concentrations at Cu/SiCN interface, grain boundary, Ta/Cu interface, and bulk were investigated along the length of a line by the electron microprobe technique. The time dependent Al concentration at the Cu/SiCN interface near the cathode end of the line is observed. These characteristics indicate that the doped Al affects the electromigration-induced Cu diffusion and does not affect the driving force. (c) 2007 American Institute of Physics.
    Scientific journal, English
  • Electromigration lifetimes and void growth at low cumulative failure probability
    Hideaki Tsuchiya; Shinji Yokogawa
    MICROELECTRONICS RELIABILITY, PERGAMON-ELSEVIER SCIENCE LTD, 46, 9-11, 1415-1420, Sep. 2006, Peer-reviwed, We have investigated electromigration (EM) lifetimes and void formation at cumulative failure probability of around 50 ppm. We carried out EM test in damascene Cu lines using sudden-death test structures. Cumulative failure probability of the test ranges from 50 ppm to 90%. To investigate the void nucleation and growth behaviour, Cu microstructures were investigated by using scanning transmission electron microscopy (S-TEM) and electron backscatter diffraction (EBSD) technique. EM lifetime shows strong correlation with the void nucleation site and the void volume. In addition, the worst case for EM lifetime is that wide angle grain boundary exists just under the via as a void nucleation site.
    Scientific journal, English
  • Scaling impacts on electromigration in narrow single-damascene Cu interconnects
    S Yokogawa; H Tsuchiya
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS BRIEF COMMUNICATIONS & REVIEW PAPERS, JAPAN SOC APPLIED PHYSICS, 44, 4A, 1717-1721, Apr. 2005, Peer-reviwed, In this paper, we present scaling impacts on electromigration-induced mass transport in narrow single-damascene Cu interconnects. Linewidths ranging from 0.12 mm to 0.20 mm were used to demonstrate the impacts. Lifetimes that are determined by resistance degradation decrease according to decreasing linewidth at a fixed current density. This is caused by a decrease in effective incubation time and an increase in drift velocity. The,product of drift velocity and the square of the linewidth has a linear dependence on current density. The activation energy is 1.2eV for the effective incubation time, and 1.1 eV for the drift velocity. The values are independent of the linewidth. The activation energy suggests that the effective incubation time is the time to void growth from the Cu/SiCN interface to the trench bottom through Cu grain boundaries. The grain boundaries provide nucleation sites for void growth in bamboo structures. Similarly, interface diffusion at the Cu/metal liner on the sidewalls of the line contributes to void growth.
    Scientific journal, English
  • シングルダマシンCu配線におけるパルス電流下のエレクトロマイグレーション挙動
    横川慎二
    電子情報通信学会誌, 88-C, 4, 253-260, 2005, Peer-reviwed
    Scientific journal, Japanese
  • Electromigration-induced void growth kinetics in SiNx-passivated single-damascene Cu lines
    S Yokogawa
    JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS, INST PURE APPLIED PHYSICS, 43, 9A, 5990-5996, Sep. 2004, Peer-reviwed, Basic electromigration characteristics of SiNx-passivated single-damascene Cu lines have been investigated. The results indicate that an effective incubation time for void growth contributes to resistance change. This effective incubation time depended inversely on the square of current density. The activation energy of the effective incubation time was 1.14 +/- 0.27 eV. The observed critical product of electromigration was approximately 5900 A/cm. The activation energy of diffusion was 0.89 +/- 0.07 eV. These results indicate that the Cu/SiNx inter-face diffusion activation energy and the effective charge number are similar to those of unpassivated Cu surface diffusion. However, the SiNx-passivated inter-face of the sample showed significantly reduced drift velocity compared to those of the unpassivated sample.
    Scientific journal, English
  • サドンデスTEGとOBIRCHを用いたダマシンCu配線のエレクトロマイグレーション評価
    横川慎二
    日本信頼性学会誌, Reliability Engineering Association of Japan (REAJ), 25, 8, 811-820, 2003, Peer-reviwed, The bimodal electromigration lifetime of damascene Cu interconnects was investigated by using a new sudden death test structure. Parameter estimation by the test structure is highly superior to that of non-sudden death approach even with a small sample size. In addition, the test structure shortens the reliability test period of electromigration. The test structure was amenable to failure analysis tools such as OBIRCH. Early failure was due to the void growth in the bottom of Via. Intrinsic failure was due to the void growth under Via.
    Scientific journal, Japanese
  • Electromigration performance of multi-level damascene copper interconnects
    S Yokogawa; N Okada; Y Kakuhara; H Takizawa
    MICROELECTRONICS RELIABILITY, PERGAMON-ELSEVIER SCIENCE LTD, 41, 9-10, 1409-1416, Sep. 2001, Peer-reviwed, Electromigration in 0.28-micron (um) wide and 0.3um thick multi-level damascene copper (Cu) interconnects with tungsten (W) studs via's have been investigated. Void growth at the cathode end of the lower line has been found as a result of electromigration. The dominant void for electromigration lifetime grows from the Cu/Via interface and grows along the Cu/SiNx interface. The activation energy of electromigration lifetime has been found to be 0.94 +/-0.11 eV, and the current density exponent 'n' has been found to be 2.03 +/-0.21. The structures in this study exhibit an incubation period of void nucleation. This was observed using the scanning transmission electron microscope (S -TEM) technique.
    From the investigation, influences of process fluctuation (e.g. lithography misalignment) on this growth have been found. The results suggest a guide of process controls specific to damascene Cu interconnects. (C) 2001 Elsevier Science Ltd. All rights reserved.
    Scientific journal, English
  • 劣化量データを用いた設備の最適保全方策とパラメータ推定
    横川慎二; 鈴木和幸
    日本設備管理学会誌, 5, 3, 3-12, 1993, Peer-reviwed
    Scientific journal, Japanese
  • 劣化量データを用いた寿命特性推定法に関する一考察 -拡散の故障メカニズムに基づく場合-
    鈴木和幸; 真木浩司; 横川慎二
    日本信頼性学会誌, 15, 2, 6-13, 1993, Peer-reviwed
    Scientific journal, Japanese
  • An Analysis of Degradation Data of a Carbon Film and the Properties of the Estimators
    Suzuki, Kazuyuki; Koji, Maki; Shinji, Yokogawa
    Stat. Sci. and Data Anal., 501-511, 1993, Peer-reviwed
    International conference proceedings, English

MISC

  • Distributed Power-Delivery Decision for a USB-PD-based Network,
    Y. Kawakita; K. Tamura; Y. Tobe; S. Yokogawa; H. Ichikawa
    15 Jun. 2022, 18th International Conference on Intelligent Enbironments, 20-23, English, Peer-reviwed
  • Controlling Power Supply Paths in VG Hub Networks Using a Hybrid Type Control Algorithm
    Kaito Oeda; Yuusuke Kawakita; Akihito Taya; Yoshito Tobe; Shinji Yokogawa; Haruhisa Ichikawa
    Although we have been developing a Virtual Grid (VG) system, where USB-PD-connected devices can alternatively provide and receive electrical power, we have not investigated the desirable power paths in a multiple-VG-Hub network. Our previous study shows that a power loss occurred inside the VG Hub. To minimize the total power loss, the number of used links needs to be minimized; the total power flow in the VG Hub network is minimized. In this paper, we have designed and implemented a cloud-based control system to execute the optimization with preceding local optimization. The experiment result has shown that the proposed hybrid type control algorithm can find the solution in 40% of the computational time on average compared with the algorithm that performs global optimization every time in the network where the solution can be found locally., IOS Press, 14 Jun. 2022, Ambient Intelligence and Smart Environments, 205-212, English, Peer-reviwed, 1875-4163, 1875-4171, conf/intenv/OedaKTTYI22
  • Time Series Clustering of CO2 Concentration Sensor Data for Risk Classification
    Y. Kawauchi; Y. Ishigaki; S. Yokogawa
    01 Jun. 2022, Indoor air 2022, 1-4, English, Peer-reviwed
  • 換気の可視化による新型コロナ感染予防
    石垣陽; 横川慎二
    01 May 2022, ビルと環境, 177, 19-29, Japanese, Introduction scientific journal
  • CO2センサーを用いた空気品質管理の要点
    横川慎二; 石垣陽
    01 May 2022, ビルと環境, 177, 4-15, Japanese, Introduction scientific journal
  • Compact model for estimating area-level photovoltaic power generation on facade surface using 3D city model and solar radiation simulation
    R. Nakazato; S. Yokogawa; H. Ichikawa; T. Ushirokawa; T. Takeda
    05 Dec. 2021, 2021 IEEE PES Innovative Smart Grid Technologies Conference – Asia, 1-5, English, Peer-reviwed
  • A maximum flow evaluation method of microgrid comprised of ultra-small microgrid components," International Conference on Emerging Technologies for Communications
    Takumi Wada; Yoshihito Tobe; Shinji Yokogawa; Haruhisa Ichikawa; Yuushuke Kawakita
    01 Dec. 2021, International Conference on Emerging Technologies for Communications, D3-2, English, Peer-reviwed
  • Accuracy verification of low-cost CO2 concentration measuring devices for general use as a countermeasure against COVID-19
    Yo Ishigaki; Koji Enoki; Shinji Yokogawa
    AbstractWithin the context of the COVID-19 pandemic, CO2 sensors that measure ventilation conditions and thereby reduce the risk of airborne infection, are gaining increasing attention. We investigated and verified the accuracy of 12 relatively low-cost sensor models that retail for less than $45 and are advertised as infection control measures on a major e-commerce site. Our results indicate that 25% of the tested sensors can be used to identify trends in CO2 concentration, if correctly calibrated. However, 67% of sensors did not respond to the presence of CO2, which suggests that a type of pseudo-technique is used to display the CO2 concentration. We recommend that these sensors are not suitable for infection prevention purposes. We also found that all 67% of the sensors that did not respond to CO2 responded strongly to alcohol. Owing to the widespread use of alcohol in preventing the spread of infectious diseases, sensors that react to alcohol can display inaccurate values, resulting in inappropriate ventilation behavior. Therefore, we strongly recommended that these sensors not be used. Based on our results, we offer practical recommendations to the average consumer, who does not have special measuring equipment, on how to identify inaccurate CO2 sensors., Cold Spring Harbor Laboratory, 31 Jul. 2021
  • Trends between indoor CO2 concentration and electricity usage through topological data analysis
    S. Endo; S. Yokogawa
    09 Mar. 2021, 2021 IEEE 3rd Global Conference on Life Sciences and Technologies,, 530-531, English, Peer-reviwed
  • Toward efficient power delivery using USB Power Delivery hub
    K. Takaie; K. Tamura; Y. Kawakita; S. Yokogawa; Y. Tobe; H. Ichikawa
    01 Oct. 2020, ACM Conference on Embedded Networked Sensor Systems, 1-15, English, Peer-reviwed
  • 故障物理に基づくワイブル解析の拡張
    横川慎二
    01 May 2020, 日本信頼性学会誌, 42, 110-115, Japanese, Introduction scientific journal
  • Practical Issues in Aggregation and Distribution of Electrical Power Amond USB-PD-Connected Devices
    K. Tamura; Y. Kawakita; Y. Tobe; S. Yokogawa; H. Ichikawa
    2020, 9th Workshop on the Reliability of Intelligent Environments, 54-61, English, Peer-reviwed
  • An Approach to Renewable-Energy Dominant Grids via Distributed Electrical Energy Platform for IoT Systems
    Haruhisa Ichikawa; Shinji Yokogawa; Yuusuke Kawakita; Kenji Sawada; Tomah Sogabe; Atsushi Minegishi; Hiromitsu Uehara
    IEEE, Oct. 2019, 2019 IEEE International Conference on Communications, Control, and Computing Technologies for Smart Grids (SmartGridComm)
  • 超スマート社会の社会品質を支えるi-パワードエネルギー・システム
    横川慎二; 市川晴久; 曽我部東馬; 澤田賢治; 早瀬修二; 大川富雄
    Oct. 2019, 品質, 49, 3, 28-31, Japanese, Peer-reviwed, Introduction other, 0386-8230, 201902228119313600
  • Grouping optimization for Wind-Photovoltaic-Battery Hybrid System using graph enumeration
    Kengo Takeda; Kenji Sawada; Shinji Yokogawa; Seiichi Shin
    23 Jan. 2019, AROB 24th 2019, 184-189, English, Peer-reviwed
  • A Simple Prediction Method for Chip-level Electromigration Lifetime using Generalized Gamma Distribution
    S. Yokogawa; K. Kunii
    2019, 2019 IEEE INTERNATIONAL RELIABILITY PHYSICS SYMPOSIUM, P.MB.9-1-P.MB.9-6, English, Peer-reviwed
  • Oxidation Structure Change of Copper Surface Depending on Accelerated Humidity
    Ploybussara Gomasang; Satoru Ogiue; Kazuyoshi Ueno; Shinji Yokogawa
    Nonlinear dependence of sheet resistance change for Cu film on humidity was observed during temperature humidity storage (THS) test to evaluate the lifetime of Cu film in long-term storage in an environment. X-ray photoelectron spectroscopy (XPS) was adopted to investigate the change of oxidation structure depending on the humidity. Relative volume ratio of Cu, Cu2O, and CuO was considered as the reason for the nonlinear dependence. The dominant reaction of oxidation changed from Cu2O to CuO between 75 and 85% relative humidity (RH) at 85 degrees C, leading to almost no reduction of Cu film thickness in spite of higher humidity., IEEE, 2018, 2018 IEEE INTERNATIONAL INTERCONNECT TECHNOLOGY CONFERENCE (IITC), 112-114, English, 2380-632X, 2380-6338, WOS:000468672900036
  • 深層学習・深層強化学習を応用したエネルギーシステムの最適化
    曽我部東馬; 横川慎二
    日本信頼性学会, 01 Jan. 2018, 日本信頼性学会誌, 40, 87-93, Japanese, Introduction scientific journal
  • Reliability Evaluation of Defect Accounted Time-Dependent Dielectric Breakdown with Competing-Mixture Distribution
    S. Yokogawa; K. Tate
    2018, 2018 IEEE INTERNATIONAL RELIABILITY PHYSICS SYMPOSIUM, P-GD.2-1-P-GD.2-4, English, Peer-reviwed
  • 日常の問題場面を用いた教材開発への一考察 ―問題解決事例の分析による目的設定の方法―
    山下雅代, 横川慎二, 鈴木和幸
    May 2017, 教材学研究, 28, 35-46
  • 再生可能エネルギー指向自律分散グリッドーバーチャルグリッドー
    横川慎二; 市川晴久; 曽我部東馬; 澤田賢治; 川喜田佑介
    日本信頼性学会, 01 Jan. 2017, 日本信頼性学会誌, 39, 1, 8-15, Japanese, Introduction scientific journal, 0919-2697, 40021068608, AN10540883
  • 社会インフラの事故・不具合の未然防止における視点
    横川慎二
    日本品質管理学会, 01 Jan. 2017, 品質, 47, 15-20, Japanese, Introduction scientific journal
  • Impacts of Censoring on Lifetime Analysis by Two-step Probability Plot in Defect Clustered TDDB
    Shinji Yokogawa
    Lifetime distribution characteristics of FEOL/MOL/BEOL time-dependent breakdown (TDDB) with defect clustering conditions were investigated by using a recently proposed two-step probability plot. This method was proposed to estimate parameters of the lifetime distribution function that is based on the defect clustering concept, and has two shape parameters. In the first step, the clustering parameter is estimated by a linearization procedure on a proposed chart. In the second step, shape and scale parameters are estimated by the slope and intercept of the plot. The impacts of censoring are investigated statistically by using Monte Carlo simulation (MCS) and the mean squared error (MSE) of the estimators., IEEE, 2017, 2017 IEEE INTERNATIONAL RELIABILITY PHYSICS SYMPOSIUM (IRPS), DG3-1-DG3-6, English, Peer-reviwed, 1541-7026, WOS:000416068500109
  • 東南アジアの在職職業訓練指導員の能力向上事業における統計的品質管理の学習
    入倉則夫, 奥猛文, 横川慎二
    May 2016, 工学教育, 64, 3, 84-89
  • Advanced Metallization for ULSI Applications
    Osamu Nakatsuka; Hoo Jeong Lee; Young Bae Park; Kazuyoshi Ueno; Shinji Yokogawa
    2016, Japanese Journal of Applied Physics, 55, 63, 0021-4922, 1347-4065, 85065701167
  • マジックダイス実験を導入した品質管理教育の実践と分析
    横川慎二,奥猛文,入倉則夫
    May 2015, 工学教育, 63, 3, 86-92
  • Middle of Line (MOL) Reliability □in between FEOL and BEOL-
    Yokogawa, Shinji
    2015, International Reliability Physics Symposium, S1.3, 1-76, English, Lecture materials, True
  • Virtual grid for renewable energy society.
    Haruhisa Ichikawa; Ashir Ahmed; Hiroshi Hanafusa; Shinji Yokogawa; Yuusuke Kawakita; Kenji Sawada; Hirohide Mikami; Noriaki Yoshikawa
    IEEE, 2015, ISGT Asia, 1-7, conf/isgta/IchikawaAHYKSMY15
  • コンタクトの信頼性 ―Siデバイスから先端パワーデバイスまで―
    横川慎二
    本稿では,Siデバイスで確立されてきたコンタクト技術の発展経緯と信頼性問題の概要,最先端デバイスプロセスにおける新たな信頼性課題,及び次世代デバイスにおけるコンタクトへの要求信頼性について述べる.アロイスパイク,Siノジュールなどの課題及びその解決方法と,先端Siデバイスで課題となってきているゲート-コンタクト間の経時絶縁破壊などの情報は,次世代デバイスにおいて起こりうる信頼性課題の未然防止に,重要な知見を与えるものである., 日本信頼性学会, 01 Jan. 2015, 日本信頼性学会誌, 37, 1, 26-33, Japanese, Introduction scientific journal, 0919-2697, 110009909695, AN10540883
  • Reliability Engineering Association of Japan
    SUZUKI Kazuyuki; YOKOGAWA Shinji; OHTA Shuuichi
    This paper introduces activities of Reliability Engineering Association of Japan (REAJ).REAJ is a volunteer group of professionals who engages in assuring reliability and safety of variousproducts, system, and human systems. REAJ organizes some symposiums and forums to encouragefor academic and industrial developments, and publishes scientific journal to introduce the latestresearch. Some study groups are contributing to mutual communications of members who havesimilar challenges., Transdisciplinary Federation of Science and Technology, 2014, Oukan (Journal of Transdisciplinary Federation of Science and Technology), 8, 1, 36-37, Japanese, 1881-7610, 130005126018
  • Lifetime Prediction for Stress-induced Voiding in Nose-shape Lines by using a Stress-diffusion Analytical Model
    Shinji Yokogawa
    A lifetime prediction model for stress-induced voiding (SIV) in Cu/low-kappa interconnects has been proposed for nose-shape lines. The stress, baseline, and nose-shape line are related by the Gompertz function. Stress-induced Cu ionic diffusion is described by a differential equation, and the lifetime is a solution of that equation. Finally, the calculated lifetime values are compared to reported values., IEEE, 2014, 2014 IEEE INTERNATIONAL RELIABILITY PHYSICS SYMPOSIUM, 97-102, English, Peer-reviwed, 1541-7026, WOS:000343833200003
  • Impact of Low-k Moisture Absorption during Queue-time on Cu-alloy/Low-k Reliability and its Suppression
    H. Tsuchiya; S. Yokogawa; H. Kunishima; T. Kuwajima; T. Usami; Y. Miura; K. Ohto; K. Fujii; M. Sakurai
    The moisture absorption impacts on electromigration (EM) and time-dependent dielectric breakdown (TDDB) were investigated in Cu alloy/low-k interconnects. A long queue time (Q-time) has a serious impact on kinetics of both EM and TDDB characteristics. The moisture absorption causes the loss of alloy effects on EM lifetime improvements. The ultra-thin SiN (UT-SiN) remarkably suppresses the moisture absorption impacts due to Q-time. It also improves kinetics degradations of EM and TDDB that depend on the moisture absorption to low-k., IEEE, 2011, 2011 IEEE INTERNATIONAL INTERCONNECT TECHNOLOGY CONFERENCE AND MATERIALS FOR ADVANCED METALLIZATION (IITC/MAM), English, Peer-reviwed, WOS:000299283100034
  • Statistics of Breakdown Field and Time-Dependent Dielectric Breakdown in Contact-to-Poly Modules
    Shinji Yokogawa; Satoshi Uno; Ichiro Kato; Hideaki Tsuchiya; Tatsuo Shimizu; Mitsuhiro Sakamoto
    In this paper, we present the results of voltage-ramp dielectric breakdown and time-dependent dielectric breakdown experiments for contact-polysilicon control gate intra-level dielectric stacks. Lifetime distribution and area scaling are discussed statistically with the analysis of global and local space deviations using the electrical method. Optimized process reliability is evaluated by performing a SRAM lifetime test that measures the early life failure rate., IEEE, 2011, 2011 IEEE INTERNATIONAL RELIABILITY PHYSICS SYMPOSIUM (IRPS), 350-357, English, Peer-reviwed, WOS:000295322100026
  • Direct Observation of RTN-induced SRAM Failure by Accelerated Testing and Its Application to Product Reliability Assessment
    K. Takeuchi; T. Nagumo; K. Takeda; S. Asayama; S. Yokogawa; K. Imai; Y. Hayashi
    A new accelerated testing scheme for detecting SRAM bit failure caused by random telegraph noise (RTN) is proposed. By repeatedly monitoring the fail bit count (FBC) under a reduced margin operation condition, increasing trend of FBC along time was clearly observed, which is believed to be caused by RTN. In addition, physics-based ultra-fast Monte Carlo RTN simulation program has been developed, which quantitatively reproduces the test results. By using the simulation calibrated by the test, product reliability against RTN can be accurately predicted., IEEE, 2010, 2010 SYMPOSIUM ON VLSI TECHNOLOGY, DIGEST OF TECHNICAL PAPERS, 189-+, English, Peer-reviwed, WOS:000287495500071
  • EFFECTIVE THERMAL CHARACTERISTICS TO SUPPRESS JOULE HEATING IMPACTS ON ELECTROMIGRATION IN CU/LOW-K INTERCONNECTS
    S. Yokogawa; H. Tsuchiya; Y. Kakuhara
    We investigated the thermal characteristics of Cu/low-k interconnects to suppress the impact of Joule heating (JH) on electromigration. The thermal time constants in multilayered Cu/low-k interconnects were experimentally investigated for the first time on the basis of the transient thermal response. Furthermore, we analyzed the use of direct radiation through stacked contact/via to suppress the temperature increase from JH. The impact of JH on the critical product of the current density and the line length was also investigated., IEEE, 2010, 2010 INTERNATIONAL RELIABILITY PHYSICS SYMPOSIUM, 717-723, English, Peer-reviwed, WOS:000287515600117
  • Novel Scalable TDDB Model for Large-Area MIM Decoupling Capacitors in High Performance LSIs
    N. Inoue; I. Kume; T. Iwaki; A. Shida; S. Yokogawa; M. Furumiya; Y. Hayashi
    Scalable TDDB model for large-area MIM capacitors is proposed to guarantee the reliability, limited by the defect-related extrinsic failure mode. Analysis based on this model leads to the guideline for the MIM design such as the dielectric thickness and capacitor area to achieve lifetime required for large decoupling capacitance on high-performance processors. Proposing TDDB model 2 reveals that highly reliable MIM capacitor with >30 mm(2), or >200 nF, per chip is realized successfully, suppressing the dynamic power-line noise in high performance LSIs., IEEE, 2009, PROCEEDINGS OF THE 2009 IEEE INTERNATIONAL INTERCONNECT TECHNOLOGY CONFERENCE, 191-+, English, Peer-reviwed, WOS:000272206600062
  • New Analysis Methods for Comprehensive Understanding of Random Telegraph Noise
    T. Nagumo; K. Takeuchi; S. Yokogawa; K. Imai; Y. Hayashi
    New analysis methods useful for understanding both complex waveforms and statistical behaviors of Random Telegraph Noise (RTN) are proposed. Complex waveforms are clearly visualized using Time Lag Plots. Bias dependence of statistically extracted average trap number is discussed, with emphasis on the importance of undetectable traps on product reliability., IEEE, 2009, 2009 IEEE INTERNATIONAL ELECTRON DEVICES MEETING, 709-+, English, Peer-reviwed, WOS:000279343900183
  • Optimization of Metallization Processes for 32-nm-node Highly Reliable Ultralow-k (k=2.4)/Cu Multilevel Interconnects Incorporating a Bilayer Low-k Barrier Cap (k=3.9)
    M. Iguchi; S. Yokogawa; H. Aizawa; Y. Kakuhara; H. Tsuchiya; N. Okada; K. Imai; M. Tohara; K. Fujii; T. Watanabe
    Reliability of 32-nm-node ultralow-k (k=2.4)/Cu multilevel interconnects incorporating a bilayer low-k barrier cap (k=3.9) was improved without excessive wiring resistance by using CuAl seed technology with high-temperature and short-time annealing. Though the increase in wiring resistivity was about 10 %, both electromigration (EM) and stress-induced voiding (SiV) reliability was clearly improved by using Cu-0.5wt%Al seed metal., IEEE, 2009, 2009 IEEE INTERNATIONAL ELECTRON DEVICES MEETING, 813-+, English, Peer-reviwed, WOS:000279343900209
  • Single-Charge-Based Modeling of Transistor Characteristics Fluctuations Based on Statistical Measurement of RTN Amplitude
    K. Takeuchi; T. Nagumo; S. Yokogawa; K. Imai; Y. Hayashi
    A single-charge-based random fluctuation model suited for analyzing both random telegraph noise (RTN) and intrinsic channel transistors (UTB-SOI. FinFET etc) is proposed. Combining a quantitative formula for the worst case V-TH shift (Delta V-TH) with measured data of RTN amplitude distributions, it is shown that RTN should not he ignored for scaled SRAM design. The model also shows that scaling of intrinsic channel FETs will be limited by the fluctuations caused by residual random charge, which rapidly increase in proportion to I/LW., JAPAN SOCIETY APPLIED PHYSICS, 2009, 2009 SYMPOSIUM ON VLSI TECHNOLOGY, DIGEST OF TECHNICAL PAPERS, 54-+, English, Peer-reviwed, WOS:000275651200020
  • V-TH FLUCTUATIONS DUE TO RANDOM TELEGRAPH SIGNAL ON WORK FUNCTION CONTROL IN HF-DOPED SILICATE GATE STACK
    T. Shimizu; I. Kato; S. Yokogawa; T. Kitagaki; J. Taniguchi; T. Suzuki; T. Tsuboi
    We investigated V-th fluctuations due to random telegraph signal (RTS) on gate work function control in Hf-doped silicate gate stack compared with the conventional impurity doping. Complex RTS were recognized for both n- and p-MOSFET. The WFC does not appreciably affect V-th fluctuations for n-and p-MOSFET. However, dopant contributes to V-th fluctuation, especially for the p-MOSFET. We found it is caused by change in V-fb fluctuation due to increase of the trap density., IEEE, 2009, 2009 IEEE INTERNATIONAL RELIABILITY PHYSICS SYMPOSIUM, VOLS 1 AND 2, 389-+, English, Peer-reviwed, WOS:000272068100065
  • Joule Heating Effects on Electromigration in Cu/Low-kappa Interconnects
    S. Yokogawa; Y. Kakuhara; H. Tsuchiya
    We investigated Joule heating effects on EM in Cu/low-kappa interconnects. The 1-D radiation mainly contributes to Joule heating. The contribution of the 2-D radiation is larger in a smaller area. However, the passive lines in the same layer do not act as a radiation activator but rather as a compounding factor. EM lifetime degradation is remarkable for dense structure due to poor 2-D radiation. High frequency pulse stress reduces Joule heating, and EM lifetime is improved due to reduction of the Joule heating., IEEE, 2009, 2009 IEEE INTERNATIONAL RELIABILITY PHYSICS SYMPOSIUM, VOLS 1 AND 2, 837-843, English, Peer-reviwed, WOS:000272068100142
  • Prediction of early failure due to non-visual defect on time-dependent dielectric breakdown of low-k dielectrics: Experimental verification of a yield-reliability model
    S. Yokogawa; D. Oshida; H. Tsuchiya; T. Taiji; T. Morita; Y. Tsuchiya; T. Takewaki
    A novel method for the prediction of early failure (EF) due to a non-visual defect is proposed for the time-dependent dielectric breakdown (TDDB) of low-k dielectrics. The yield-reliability relation model is modified to evaluate the EFs. The effectiveness of the novel method is experimentally confirmed by using a 65 nm technology node. A bimodal lifetime distribution is used to evaluate the lifetime distribution. The probability of EF can be estimated based on the basis of the results and the defect density of each wafer., IEEE, ELECTRON DEVICES SOC & RELIABILITY GROUP, 2008, 2008 IEEE INTERNATIONAL RELIABILITY PHYSICS SYMPOSIUM PROCEEDINGS - 46TH ANNUAL, 144-+, English, Peer-reviwed, 1541-7026, WOS:000257615900022
  • Impurity doping effects on electromigration performance of scaled-down Cu interconnects
    Shinji Yokogawa; Hideaki Tsuchiya
    To study of the impurity effect of electromigration kinetics, we have investigated the effects of Al doping in Cu interconnects. The effects of Al doping on the incubation time, drift velocity, and critical product of electromigration were investigated. The drift velocity of Cu mass transport in CuAl alloys decreases with an increase in the concentration of Al atoms. The observed critical product of electromigration is 1500 A/cm, and it is independent of the Al concentration. The activation energy of the normalized drift velocity increases with an increase in Al concentration. The Al concentrations at Cu/SiCN interface, grain boundary, Ta/Cu interface, and bulk were investigated along the length of a line by the electron microprobe technique. The time dependent Al concentration at the Cu/SiCN interface near the cathode end of the line is observed. These characteristics indicate that the doped Al affects the electromigration-induced Cu diffusion and does not affect the driving force., AMER INST PHYSICS, 2007, STRESS-INDUCED PHENOMENA IN METALLIZATION, 945, 82-97, English, 0094-243X, WOS:000252104700008
  • Analytical study of impurity doping effects on electromigration of Cu interconnects by employing comprehensive scattering model
    S. Yokogawa; Y. Kakubara; H. Tsuchiya; K. Kikuta
    We investigated the impurity (Al) doping effect on resistivity of damascene Cu interconnects with decomposing into surface, grain boundary, and impurity scattering factors by employing comprehensive scattering model. The surface scattering is dominant for resistivity increasing. Electromigration-induced Cu drift is suppressed as Al concentration increases. The electromigration lifetime is improved by suppression of the Cu diffusion due to piled-up Al at the top surface of Cu interconnects., IEEE, 2007, 2007 IEEE INTERNATIONAL RELIABILITY PHYSICS SYMPOSIUM PROCEEDINGS - 45TH ANNUAL, 117-+, English, Peer-reviwed, 1541-7026, WOS:000246989600020
  • A novel resistivity measurement technique for scaled-down Cu interconnects implemented to reliabitity-focused automobile applications
    S. Yokogawa; K. Kikuta; H. Tsuchiya; T. Takewaki; M. Suzuki; H. Toyoshima; Y. Kakuhara; N. Kawahara; T. Usami; K. Ohto; K. Fujii; Y. Tsuchiya; K. Arita; K. Motoyama; M. Tohara; T. Taiji; T. Kurokawa; M. Sekine
    A novel resistivity measurement technique has been proposed for scaled-down Cu interconnects viewing the high-reliability automobile applications. This technique enables to detect the interconnect resistivity dependence on impurity concentration, free from dimension dependence. Using this technique, we investigated impacts of impurity concentration on three types of Cu interconnects: 1) CoWP cap, 2) PECVD Self-Aligned Barrier (PSAB), 3) CuAl interconnects and clarified the trade-offs between resistivity and reliability. We have found that CoWP cap shows not only high-reliability but also an outstanding efficiency in suppression of resistance increase due to impurity-induced scattering, indicating that it is the most viable candidate for automobile applications in 32nm generation and beyond., IEEE, 2006, 2006 INTERNATIONAL ELECTRON DEVICES MEETING, VOLS 1 AND 2, 772-+, English, Peer-reviwed, WOS:000247357700193
  • Effects of Al doping on electromigration performance of narrow single damascene Cu interconnects
    S. Yokogawa; H. Tsuchiya
    IEEE, 2006, 2006 IEEE INTERNATIONAL RELIABILITY PHYSICS SYMPOSIUM PROCEEDINGS - 44TH ANNUAL, 667-+, English, Peer-reviwed, 1541-7026, WOS:000240855800130
  • Stress relaxation in dual-damascene Cu interconnects to suppress stress-induced voiding
    M. Kawano; T. Fukase; Y. Yamamoto; T. Ito; S. Yokogawa; H. Tsuda; Y. Kunimune; T. Saitoh; K. Ueno; M. Sekine
    Stress-induced voiding (SIV) was investigated for 130 nm node dual-damascene Cu interconnects. Three SIV failure modes were revealed by TEM analyses. Cumulative failure was investigated at various metal widths, via shape and via position on a metal line at 150°C at which the maximum failure rate was observed. Stress-induced failure at narrow Cu line was also observed, which is associated with tensile stress in Cu calculated by 3D finite element method (FEM) stress analysis. Stress relaxation by dielectric structure and quenching process were demonstrated based on stress simulation, thus the resulting SIV failure was suppressed., 2003, Proceedings of the IEEE 2003 International Interconnect Technology Conference, IITC 2003, 210-212, 28744446852
  • A robust embedded ladder-oxide/Cu multilevel interconnect technology for 0.13 mu m CMOS generation
    N Oda; S Ito; T Takewaki; H Kunishima; N Hironaga; Honma, I; H Namba; S Yokogawa; T Goto; T Usami; K Ohto; A Kubo; H Aoki; M Suzuki; Y Yamamoto; S Watanabe; T Takeda; K Yamada; M Kosaka; T Horiuchi
    A robust embedded Ladder-oxide(k=2.9)/Cu) multilevel interconnect is demonstrated for 0.13 mum CMOS generation. A stable ladder-oxide IMD is integrated into the Cu metallization with minimum wiring pitch of 0.34 mum, and a single damascene (S/D) Cu-plug structure is applied. An 18 % reduction in wiring capacitance is obtained compared with SiO2 IMD. The stressmigration lifetime of vias on wide metals for S/D Cu-plug structure is much longer dim dual damascene (D/D). The reliability test results such as electromigration (EM), TDDB of Cu interconnect and pressure cooker test (PCT) are quite acceptable. Moreover, high flexibility in thermal design and packaging is obtained., IEEE, 2002, 2002 SYMPOSIUM ON VLSI TECHNOLOGY, DIGEST OF TECHNICAL PAPERS, 34-35, English, Peer-reviwed, WOS:000176856300012
  • Full-0.56μm Pitch Copper Interconnects for a High Performance 0.15-μm CMOS Logic Device
    M. Iguchi; T. Takewaki; Y. Matsubara; Y. Kunimune; N. Ito; Y. Tsuchiya; T. Matsui; K. Fujii; K. Motoyama; K. Sugai; A. Kubo; M. Suzuki; H. Tachibana; A. Nishizawa; K. Nakabeppu; S. Yamasaki; S. Yokogawa; Y. Yamamoto; T. Kunugi; S. Nakata; M. Kagamihara; A. Shida; S. Nakamoto; H. Gomi
    1999, International Electron Device Meeting, 615-618, English, Peer-reviwed, 80011719431

Books and other publications

  • 車載用リチウムイオン電池のリユース技術と実際例
    横川慎二; 中里諒
    Contributor, 第1編第1章 電気化学インピーダンス法と階層ベイズを用いたリチウムイオン二次電池の容量劣化量診断技術, NTS, Aug. 2023, 9784860438500
  • 加速試験の実施とモデルを活用した製品寿命予測
    横川慎二
    Japanese, Contributor, 第9章第2節 スモールデータに基づく機器の寿命予測, 555p, 技術情報協会, Jun. 2023, 9784861049552
  • 信頼性試験技術
    Scholarly book, Japanese, Joint work, 日科技連出版社, 31 Dec. 2019
  • 新版信頼性ハンドブック
    日本信頼性学会編
    Dictionary or encycropedia, Japanese, Joint editor, 日科技連出版, 2014
  • LSIの信頼性
    二川 清; 塩野 登; 横川 慎二; 福田 保裕; 三井 泰裕
    Scholarly book, Japanese, Contributor, 日科技連出版, 2010
  • 信頼性データ解析
    鈴木和幸; 益田昭彦; 石田勉; 横川慎二
    Scholarly book, Japanese, Contributor, 日科技連出版, 2009
  • LSIテスティングハンドブック
    LSIテスティング学会
    Dictionary or encycropedia, Japanese, Contributor, オーム社, 2008
  • 信頼性七つ道具 R7
    Scholarly book, Japanese, Contributor, 日科技連出版, 2008
  • 金属微細配線におけるマイグレーションのメカニズムと対策
    Scholarly book, Japanese, Contributor, サイエンス&テクノロジー, 2006

Lectures, oral presentations, etc.

  • 感染症予防難易度の高い社会福祉施設の空気質管理
    横川慎二; 石垣陽; 喜多村紘子; 齋藤彰
    第14回横幹連合コンファレンス, Invited
    16 Dec. 2023
    16 Dec. 2023- 17 Dec. 2023
  • Effects of defect clustering on the shape of TDDB lifetime distribution and screening effectiveness
    Koichi Endo; Shinji Yokogawa
    Poster presentation, English, Advanced Metallization Conference 2023; 32nd Asian Session, Peer-reviewed
    12 Oct. 2023
    12 Oct. 2023- 13 Oct. 2023
  • CO2センサを用いたフィールドワークと時系列データ解析に基づくエアロゾル感染リスク診断
    川内雄登; 横川慎二; 石垣陽
    Oral presentation, Japanese, 日本信頼性学会第31回春季信頼性シンポジウム
    01 Jun. 2023
    01 Jun. 2023- 01 Jun. 2023
  • MOL and BEOL Reliability
    Shinji Yokogawa
    Public discourse, English, IEEE International Reliability Physics Symposium, Invited
    26 Mar. 2023
  • 保育園・幼稚園・高齢者施設の感染症抑制に向けた課題と現状分析
    横川慎二; 石垣陽; 喜多村紘子; 齋藤彰
    第13回横幹連合コンファレンス
    18 Dec. 2022
  • CO2センサーデータの時系列クラスタリングによるマイクロ飛沫感染リスクの診断方法
    川内雄登; 石垣陽; 横川慎二
    第13回横幹連合コンファレンス
    18 Dec. 2022
  • Simulation of area-level photovoltaic power generation on city facade for a power generation in smart grids
    Li Guanglei; Shinji Yokogawa
    English, Grand Renewable Energy 2022 Conference, Peer-reviewed
    16 Dec. 2022
  • USB PD based Microgrid for Accelerating the Power Grid Transition to a Low Carbon Future
    Haruhisa Ichikawa; Shinji Yokogawa; Yuusuke Kawakita; Yoshito Tobe
    2022 IEEE 8th World Forum on Internet of Things (WF-IoT), IEEE, http://xplorestaging.ieee.org/ielx7/10151825/10152024/10152187.pdf?arnumber=10152187
    26 Oct. 2022
    26 Oct. 2022- 26 Oct. 2022
  • Statistical Modeling of Vth Distribution in Ovonic Threshold Switches
    Shinji Yokogawa
    Oral presentation, English, Advanced Metallization Conference 2022, Asian session, International conference
    13 Oct. 2022
  • 情報通信技術が切り拓く我が国のカーボンニュートラル
    横川慎二
    Invited oral presentation, Japanese, 会津大学学際研究フォーラム2022, Invited, Domestic conference
    22 Aug. 2022
  • Distributed Power-Delivery Decision for a USB-PD-based Network,
    Y. Kawakita; K. Tamura; Y. Tobe; S. Yokogawa; H. Ichikawa
    English, 18th International Conference on Intelligent Enbironments
    15 Jun. 2022
    15 Jun. 2022- 15 Jun. 2022
  • Controlling Power Supply Paths in VG Hub Networks Using a Hybrid Type Control Algorithm
    Kaito Oeda; Yuusuke Kawakita; Akihito Taya; Yoshito Tobe; Shinji Yokogawa; Haruhisa Ichikawa
    English, Ambient Intelligence and Smart Environments, IOS Press, https://ebooks.iospress.nl/pdf/doi/10.3233/AISE220043, Although we have been developing a Virtual Grid (VG) system, where USB-PD-connected devices can alternatively provide and receive electrical power, we have not investigated the desirable power paths in a multiple-VG-Hub network. Our previous study shows that a power loss occurred inside the VG Hub. To minimize the total power loss, the number of used links needs to be minimized; the total power flow in the VG Hub network is minimized. In this paper, we have designed and implemented a cloud-based control system to execute the optimization with preceding local optimization. The experiment result has shown that the proposed hybrid type control algorithm can find the solution in 40% of the computational time on average compared with the algorithm that performs global optimization every time in the network where the solution can be found locally.
    14 Jun. 2022
    14 Jun. 2022- 14 Jun. 2022
  • Time Series Clustering of CO2 Concentration Sensor Data for Risk Classification
    Y. Kawauchi; Y. Ishigaki; S. Yokogawa
    English, Indoor air 2022
    01 Jun. 2022
    01 Jun. 2022- 01 Jun. 2022
  • 熱流体シミュレーションと応答曲面法を用いたX線検診車の換気とリスクの分析
    平出大誠; 川内雄登; 石垣陽; 横川慎二; 齋藤彰; 喜多村紘子
    Oral presentation, Japanese, 第30回日本信頼性学会春季信頼性シンポジウム, Domestic conference
    31 May 2022
  • 建物沿面を考慮した都市エリアレベルの太陽光発電量推定モデル
    中里 諒; 横川慎二; 市川晴久; 後川知仁; 武田 隆
    Oral presentation, Japanese, 電子情報通信学会, 電子通信エネルギー技術研究会, Domestic conference
    25 Jan. 2022
  • Compact model for estimating area-level photovoltaic power generation on facade surface using 3D city model and solar radiation simulation
    R. Nakazato; S. Yokogawa; H. Ichikawa; T. Ushirokawa; T. Takeda
    English, 2021 IEEE PES Innovative Smart Grid Technologies Conference – Asia
    05 Dec. 2021
    05 Dec. 2021- 05 Dec. 2021
  • A maximum flow evaluation method of microgrid comprised of ultra-small microgrid components," International Conference on Emerging Technologies for Communications
    Takumi Wada; Yoshihito Tobe; Shinji Yokogawa; Haruhisa Ichikawa; Yuushuke Kawakita
    English, International Conference on Emerging Technologies for Communications
    01 Dec. 2021
    01 Dec. 2021- 01 Dec. 2021
  • 故障物理に基づくデバイスの信頼性モデリング
    横川慎二
    Invited oral presentation, Japanese, OR学会・4部会・グループ合同研究会 ~確率モデルの新展開~, Domestic conference
    23 Oct. 2021
  • 先端デバイスの故障メカニズムに基づく チップレベル信頼性設計
    横川慎二
    Public discourse, Japanese, 第31回RCJ電子デバイスの信頼性シンポジウム, Invited, Domestic conference
    22 Oct. 2021
  • Society 5.0の基盤としてのデータ収集・分析・利活用
    横川慎二
    Invited oral presentation, Japanese, 第28回IoT特別研究会(RC-88), Invited, Domestic conference
    31 Aug. 2021
  • 利用調査データに基づくユーザーペルソナの抽出とバッテリー劣化量との相関分析
    浅野実; 横川慎二; 石垣陽; 冨永潤一; 粟津浜一
    Oral presentation, Japanese, モバイル '21, Domestic conference
    20 Jul. 2021
  • パブリックスペースにおける CO 2 濃度 センシングを用いたリスク解析
    川内雄登; 石垣陽; 横川慎二
    Oral presentation, Japanese, 第50回信頼性・保全性・安全性シンポジウム, Domestic conference
    29 Jun. 2021
  • 利用調査データに基づく ユーザーペルソナの抽出とバッテリー劣化量との相関分析
    浅野実; 石垣陽; 横川慎二; 冨永潤一; 粟津浜一
    Oral presentation, Japanese, 第50回信頼性・保全性・安全性シンポジウム, Domestic conference
    29 Jun. 2021
  • CO2センサーネットワークによるホールの換気量の評価とリアルタイム可視化
    川内登; 浅野実; 中里諒; 黒良内生; 中嶋洋貴; 平出大誠; 遠藤幸一; 石垣陽; 横川慎二
    Oral presentation, Japanese, 第29回環境化学討論会, Domestic conference
    01 Jun. 2021
  • Trends between indoor CO2 concentration and electricity usage through topological data analysis
    S. Endo; S. Yokogawa
    Oral presentation, English, 2021 IEEE 3rd Global Conference on Life Sciences and Technologies, International conference
    09 Mar. 2021
  • ユーザーの利用調査データに基づくモバイル端末のバッテリー劣化傾向の診断
    浅野実; 横川慎二
    Oral presentation, Japanese, 電子情報通信学会,信頼性研究会, Domestic conference
    12 Feb. 2021
  • 航空LiDARデータとGISソフトウェアを用いた太陽光沿面発電における検討
    中里 諒; 野秋拓真; 横川慎二; 市川晴久; 後川知仁; 武田 隆
    Oral presentation, Japanese, 電子情報通信学会, 電子通信エネルギー技術研究会, Domestic conference
    25 Jan. 2021
  • VG-Hub制御・管理のクラウド化に関する検討
    大條 海渡; 川喜田 佑介; 田谷 昭仁; 戸辺 義人; 横川 慎二; 市川 晴久
    Oral presentation, Japanese, 第29回マルチメディア通信と分散処理ワークショップ, Domestic conference
    2021
  • Practical Issues in Aggregation and Distribution of Electrical Power Amond USB-PD-Connected Devices
    K. Tamura; Y. Kawakita; Y. Tobe; S. Yokogawa; H. Ichikawa
    Oral presentation, English, 9th Workshop on the Reliability of Intelligent Environments, International conference
    2021
  • CO2センサーを活用した循環器検診車内の換気可視化の検討
    斎藤彰; 石垣陽; 横川慎二; 川内雄登; 田中晴美; 浅野美穂; 小川美紀; 鎌田麻衣; 石川正吾; 齋藤泰紀
    Oral presentation, Japanese, 第62回日本人間ドック学会学術大会, Domestic conference
    2021
  • 分散電力の統合とグリッドレジリエンス確保のためのデバイス識別と蓄電池診断技術
    横川慎二; 浅野実; 中里諒
    Oral presentation, Japanese, 第63回自動制御連合講演会, Domestic conference
    13 Nov. 2020
  • USB-PDによるポリシーアウェアDCパワーネットワーキング
    川喜田佑介; 高家和輝; 田村光汰; 戸辺義人; 市川晴久; 横川慎二
    Oral presentation, Japanese, 第63回自動制御連合講演会, Domestic conference
    13 Nov. 2020
  • 超小型電力システムを単位に再構成可能なマイクログリッド
    市川晴久; 横川慎二; 戸辺義人; 川喜田佑介
    Oral presentation, Japanese, 第63回自動制御連合講演会
    13 Nov. 2020
  • Ambient Intelligence(環境知能)によるフリーアドレススペースのリスク評価
    横川慎二; 石垣陽; 遠藤駿; 高原廉
    Oral presentation, Japanese, 第11回横幹連合コンファレンス, Domestic conference
    08 Oct. 2020
  • Toward efficient power delivery using USB Power Delivery hub
    K. Takaie; K. Tamura; Y. Kawakita; S. Yokogawa; Y. Tobe; H. Ichikawa
    English, ACM Conference on Embedded Networked Sensor Systems
    01 Oct. 2020
    01 Oct. 2020- 01 Oct. 2020
  • 電気化学インピーダンス法と階層ベイズによるリチウムイオン二次電池の容量劣化量診断
    中里諒; 横川慎二
    Oral presentation, Japanese, 電子情報通信学会、信頼性研究会8月度研究会, Domestic conference
    28 Aug. 2020
  • USB-PDを活用した電力の合成分配制御に関する検討
    田村光汰; 川喜田佑介; 戸辺義人; 横川慎二; 市川晴久
    Oral presentation, Japanese, 第82回情報処理学会全国大会, Domestic conference
    21 Feb. 2020
  • 極微細配線の課題解決に向けた金属間化合物の可能性
    小池淳一; チェン リンハン; 横川慎二
    Invited oral presentation, Japanese, 電子情報通信学会,SDM研究会, Invited, Domestic conference
    07 Feb. 2020
  • Toward efficient power delivery using USB Power Delivery hub
    K. Takaie; K. Tamura; Y. Kawakita; S. Yokogawa; Y. Tobe; H. Ichikawa
    Oral presentation, English, ACM Conference on Embedded Networked Sensor Systems, International conference
    01 Feb. 2020
  • ビッグ/スモールデータ時代の信頼性解析
    横川慎二
    Invited oral presentation, Japanese, JEITA 半導体信頼性認定ガイドラインセミナー, Invited, Domestic conference
    31 Jan. 2020
  • 人対機械システムにおける信頼成長の分析
    横川慎二; 遠藤駿
    Oral presentation, Japanese, 電子情報通信学会,信頼性研究会, Domestic conference
    13 Dec. 2019
  • i-パワードエネルギーによるデータ駆動型社会基盤と不具合未然防止
    横川慎二; 市川晴久; 澤田賢治; 曽我部東馬; 川喜田佑介
    Oral presentation, Japanese, 第10回横幹連合コンファレンス, Domestic conference
    30 Nov. 2019
  • ワイブルベイズ統計モデリングにおける故障物理情報の応用
    横川慎二
    Public discourse, Japanese, 第29回RCJ電子デバイスの信頼性シンポジウム, Invited, Domestic conference
    28 Nov. 2019
  • An Approach to Renewable-Energy Dominant Grids via Distributed Electrical Energy Platform for IoT Systems
    H. Ichikawa; S. Yokogawa; Y. Kawakita; K. Sawada; T. Sogabe; A. Minegishi; H. Uehara
    Oral presentation, English, IEEE International Conference on Communications, Control, and Computing Technologies for Smart Grids, International conference
    21 Oct. 2019
  • Chip-level Electromigration Evaluation using GENG estimations
    Shinji Yokogawa; Kyosuke kunii; Ryou Nakazato
    Poster presentation, English, Advanced Metallization Conference 2019, Asian session, International conference
    10 Oct. 2019
  • Humidity Reliability of a Commercial Flash Memory for Long Term Storage
    T. Murota; T. Mimura; P. Gomasang; S. Yokogawa; K. Ueno
    Poster presentation, English, Advanced Metallization Conference 2019, Asian session, International conference
    10 Oct. 2019
  • エゾシカ肉の電気的特性評価とそのおいしさの解析
    武山真弓; 横川慎二; 佐藤勝; 安井崇
    Oral presentation, Japanese, 電子情報通信学会 電子部品・材料研究会, Domestic conference
    Aug. 2019
  • 信頼性加速試験における小サンプルサイズでの解析精度に関するシミュレーション研究
    遠藤 幸一; 瀬戸屋 孝; 國井 喬介; 横川 慎二
    Oral presentation, Japanese, 第49回信頼性・保全性シンポジウム, Domestic conference
    18 Jul. 2019
  • 局所クラスタ化した欠陥を伴うTDDB寿命分布のパラメータ推定精度の研究
    國井喬介; 遠藤駿; 中里諒; 横川慎二
    Oral presentation, Japanese, 第49回信頼性・保全性シンポジウム, Domestic conference
    18 Jul. 2019
  • クラスター欠陥とストレス分布に基づく先端デバイスの信頼度モデリング
    横川慎二; 國井喬介
    Oral presentation, Japanese, 電子情報通信学会,信頼性研究会, Domestic conference
    14 Jun. 2019
  • 自動/有人レジに対する不満の差異に着目した対人自動システムへの信頼構造の分析
    森田裕; 横川慎二
    Oral presentation, Japanese, 第27回日本信頼性学会春季信頼性シンポジウム, Domestic conference
    31 May 2019
  • 「数の難題」,再来 ーLSI信頼性の果たすものとこれからー
    横川慎二
    Invited oral presentation, Japanese, JEITA 半導体デバイス信頼性セミナー, Invited, JEITA, Domestic conference
    24 May 2019
  • 「数の難題」,再来 ーLSI信頼性の果たすものとこれからー
    横川慎二
    Invited oral presentation, Japanese, JEITA 半導体デバイス信頼性セミナー, Invited, Domestic conference
    24 May 2019
  • Reliability statistics for next-generation interconnects -The combination of physical modeling and statistical techniques-
    S. Yokogawa
    Invited oral presentation, English, 2019 MRS Spring Meeting, Invited, International conference
    23 Apr. 2019
  • ベイズ推測によるワイブル初期故障分布の推定・評価
    横川慎二
    Public discourse, Japanese, 第28回RCJ電子デバイスの信頼性シンポジウム, Invited, Domestic conference
    27 Nov. 2018
  • グラフ列挙による風力・太陽光・蓄電池複合システムの重複グルーピング最適化
    武田健吾; 澤田 賢治; 横川 慎二; 新誠一
    Oral presentation, Japanese, 計測自動制御学会システム・情報部門学術講演会, Domestic conference
    25 Nov. 2018
  • 多層配線の故障物理メカニズムと信頼度予測
    横川慎二
    Invited oral presentation, Japanese, JEITA 半導体デバイス信頼性セミナー, Invited, Domestic conference
    16 Nov. 2018
  • 局所クラスタ化した欠陥を伴うTDDB の寿命分布のパラメータ推定精度の研究
    國井喬介; 遠藤駿; 横川慎二
    Poster presentation, Japanese, ADMETA Satellite Workshop, Domestic conference
    02 Nov. 2018
  • エレクトロマイグーション のチップレベル 寿命分布の考察
    横川慎二; 國井喬介
    Poster presentation, Japanese, ADMETA Satellite Workshop, Domestic conference
    02 Nov. 2018
  • Parameter estimation accuracy of TDDB lifetime distribution with clustering defects using the Bayesian approach
    Kyosuke Kunii; Shun Endo; Shinji Yokogawa
    Oral presentation, English, Advanced Metallization Conference 2018, Asian session, Tokyo, International conference
    12 Oct. 2018
  • グローバル展開を前提とした超スマート社会の確立を目指すエネルギープラットフォーム
    市川 晴久; 横川 慎二; 川喜田 佑介
    Oral presentation, Japanese, 第9回横幹連合コンファレンス, Domestic conference
    06 Oct. 2018
  • グルーピング列挙による風力・太陽光・蓄電池複合システムの重複グルーピング最適化
    武田健吾; 澤田 賢治; 横川 慎二; 新誠一
    Oral presentation, Japanese, 第9回横幹連合コンファレンス, Domestic conference
    06 Oct. 2018
  • 創発的不具合における機能共鳴の分析と分類
    横川 慎二
    Oral presentation, Japanese, 第9回横幹連合コンファレンス, Domestic conference
    06 Oct. 2018
  • Temperature and Humidity Acceleration to Establish Lifetime Prediction Model for Cu-based Metallization
    P. Gomasang; S. Ogiue; S. Yokogawa; K. Ueno
    Oral presentation, English, International Conference on Solid State Devices and Materials, 応用物理学会, International conference
    10 Sep. 2018
  • アンケート分析によるエゾシカ肉の旨味評価と電気的測定評価との関連
    武山真弓; 横川慎二; 佐藤勝; 安井崇
    Oral presentation, Japanese, 電子情報通信学会電子部品・材料研究会8月度研究会, Domestic conference
    10 Aug. 2018
  • 畳み込みニューラルネットワークを用いたシステムの特性劣化の特徴量抽出と運用条件検討への応用
    遠藤駿; 横澤成望; 川上紗野花; 國井喬介; 横川慎二
    Oral presentation, Japanese, 信頼性・保全性シンポジウム, 日本科学技術連盟, Domestic conference
    19 Jul. 2018
  • Oxidation Structure Change of Copper Surface Depending on Accelerated Humidity
    P. Gomasang; S. Ogiue; K. Ueno; S. Yokogawa
    Oral presentation, English, IEEE International Interconnect Technology Conference, IEEE, International conference
    14 Jun. 2018
  • 特徴グラフを用いた汎用型CNN深層学習手法の開発
    高橋 慧; 沼尻 匠; 曽我部 完; 坂本 克好; 山口 浩一; 横川 慎二; 曽我部 東馬
    Oral presentation, Japanese, 人工知能学会全国大会, Domestic conference
    05 Jun. 2018
  • 量子事故符号化器の開発
    黄川田優太; 坂本克好; 山口浩一; 横川慎二; 曽我部東馬
    Oral presentation, Japanese, 人工知能学会全国大会, Domestic conference
    05 Jun. 2018
  • Hybrid Policy Gradient for Deep Reinforcement Learning
    P. S. THAKUR; M. SOGABE; K. SAKAMOTO; K. YAMAGUCHI; D. B. MALLA; S. YOKOGAWA; T. SOGABE
    Oral presentation, English, 人工知能学会全国大会, Domestic conference
    05 Jun. 2018
  • Physical and Statistical Analysis and Methodologies for Realizing Automotive-Level Extremely Low Defect Densities (FEOL/MOL/BEOL)
    Shinji Yokogawa
    Public discourse, English, International Conference on IC Design and Technology, Invited, IEEE, Otranto, Italy, International conference
    04 Jun. 2018
  • 風力・太陽光・蓄電池複合システムにおけるグルーピング最適化の検証
    武田健吾; 澤田賢治; 横川慎二; 新誠一
    Oral presentation, Japanese, 第30回自律分散システム・シンポジウム, Domestic conference
    28 Jan. 2018
  • テキストマイニングと機能共鳴分析法を用いた自動車のリコール情報の分析
    横川慎二; 國井喬介
    Oral presentation, Japanese, 第30回日本信頼性学会秋季信頼性シンポジウム, Domestic conference
    27 Nov. 2017
  • 畳み込みニューラルネットワークを用いた設備特性劣化のオンラインモニタリングデータ分析
    横澤成望; 横川慎二
    Oral presentation, Japanese, 第30回日本信頼性学会秋季信頼性シンポジウム, Domestic conference
    27 Nov. 2017
  • システムの不具合における創発性の影響について
    横川慎二
    Oral presentation, Japanese, 第60回自動制御連合講演会, Domestic conference
    10 Nov. 2017
  • Statistical evaluation of lifetime distribution with defect clustering by using two-step probability plot and multi-link test scheme
    Kazuki Tate; Shinji Yokogawa
    Poster presentation, English, Advanced Metallization Conference 2017, Asian session, Tokyo, International conference
    19 Oct. 2017
  • Application of fault tree analysis for interconnect reliability assessment
    Shinji Yokogawa; Kyosuke Kunii
    Poster presentation, English, Advanced Metallization Conference 2017, Asian session, Tokyo, International conference
    19 Oct. 2017
  • リチウムイオン二次電池の劣化における二変量ストレスの交互作用に着目した統計モデリング
    横川慎二; 國井喬介; 横澤成望
    Oral presentation, Japanese, 2017年電気化学秋季大会, 電気化学会, 長崎, Domestic conference
    10 Sep. 2017
  • 半導体集積回路配線の信頼性課題と寿命予測
    横川慎二
    Invited oral presentation, Japanese, 応用物理学会春季学術講演会, Invited, Domestic conference
    15 Mar. 2017
  • A simple method of parameter estimating for time-dependent clustering model in MOL/BEOL TDDB lifetime
    Shinji Yokogawa
    Oral presentation, English, Advanced Metallization Conference 2016, Asian session, International conference
    20 Oct. 2016
  • リチウムイオン二次電池の劣化における充放電サイクルと待機時間の影響
    横川慎二
    Oral presentation, Japanese, 日本信頼性学会春季信頼性シンポジウム, Domestic conference
    23 May 2016
  • A simulation study of impacts of global and local space variations on lifetime distribution in MOL/BEOL TDDB
    Shinji Yokogawa
    Oral presentation, English, Advanced Metallization Conference 2015, Asian session, International conference
    17 Sep. 2015
  • Middle of Line (MOL) Reliability - in between FEOL and BEOL -
    Shinji Yokogawa
    Public discourse, English, International Reliability Physics Symposium, Invited, International conference
    19 Apr. 2015
  • An analysis of statistical characteristics of lifetime distribution based on the defect clustering for MOL/BEOL TDDB
    Shinji Yokogawa
    Poster presentation, English, Advanced Metallization Conference 2014: 24th Asian Session, International conference
    23 Oct. 2014
  • Lifetime Prediction Model for Stress-induced Voiding in Cu/low-k Interconnects
    Shinji Yokogawa
    Oral presentation, English, Advanced Metallization Conference 2013: 23rd Asian Session, International conference
    08 Oct. 2013

Courses

  • Quality Control Ⅰ
    Oct. 2023 - Present
    The University of Electro-Communications
  • リスクマネジメント論
    Apr. 2023 - Present
    電気通信大学大学院
  • コンピュータリテラシー
    Apr. 2021 - Present
    電気通信大学
  • 信頼性と設計
    Oct. 2020 - Present
    早稲田大学大学院
  • 基礎科学実験A
    Oct. 2018 - Present
    The University of Electro-Communications
  • 信頼性工学
    Oct. 2016 - Present
    The University of Electro-Communications
  • Special Lecture on Mechanical and Electrical Engineering; Energy Infrastructure Paradigm and System Resilience Toward Carbon Neutrality
    Sep. 2023 - Sep. 2023
    Kitami Institute of Technology
  • Statistics Analysis
    2016
    Polytechnic University of Japan
  • Statistics Analysis
    2015
    Polytechnic University of Japan
  • 大学院総合コミュニケーション科学
    The University of Electro-Communications
  • 輪講B(学域・K課程)
    電気通信大学
  • 科学と人間(4)
    津田塾大学
  • 大学院総合コミュニケーション科学
    電気通信大学
  • ソフトウェア品質保証(集中講義)
    筑波大学
  • イノベイティブ総合コミュニケーションデザイン1
    The University of Electro-Communications
  • 信頼性工学特論
    職業能力開発総合大学校・職業能力開発研究学域
  • イノベイティブ総合コミュニケーションデザイン2
    The University of Electro-Communications
  • 統計解析特論
    職業能力開発総合大学校
  • オペレーションズリサーチ特論
    職業能力開発総合大学校・短期養成課程(国費留学生)
  • システム工学特論
    職業能力開発総合大学校・高度養成課程
  • 信頼性工学特論
    職業能力開発総合大学校・短期養成課程(国費留学生)
  • 品質管理
    職業能力開発総合大学校・総合課程

Affiliated academic society

  • 電気学会
  • 電子情報通信学会
  • IEEE
  • 応用物理学会
  • 日本品質管理学会
  • 日本信頼性学会

Research Themes

  • 小規模創電・蓄電の統合運用を可能にするインターネット型電力プラットフォーム
    横川 慎二
    日本学術振興会, 科学研究費助成事業 基盤研究(B), 電気通信大学, 基盤研究(B), 23H01636
    01 Apr. 2023 - 31 Mar. 2027
  • ポスト5G情報通信システム基盤強化研究開発事業/先端半導体製造技術の開発/Beyond 2nm及び短TAT半導体製造に向けた技術開発/国際連携による次世代半導体製造技術開発 《Beyond 2nm世代向け半導体技術開発》
    技術研究組合最先端半導体技術センター(NEDO再委託), Principal investigator
    Jan. 2024 - Jan. 2027
  • 都市型太陽電池による創電・蓄電の強化推進事業
    東京都, 大学研究者による事業提案制度, Principal investigator
    Apr. 2023 - Mar. 2026
  • 信頼性・安全性トラブル未然防止へのモバイルIoTモニタリングシステムの開発と展開
    鈴木和幸
    01 Apr. 2020 - 31 Mar. 2025
  • 円筒形太陽電池を用いた可搬式創蓄電設備の実証
    調布市, 子供・長寿・居場所区市町村包括補助事業, Principal investigator
    Nov. 2022 - Mar. 2025
  • 感染症予防難易度の高い社会福祉施設における環境特徴量抽出と空気質管理方法に関する研究
    横川慎二; 石垣陽; 喜多村紘子
    公益財団法人カシオ科学振興財団
    Nov. 2022 - Oct. 2023
  • 保育施設における感染症予防のための空気質管理方法と換気ガイドライン策定に関する研究
    横川慎二; 石垣陽; 喜多村紘子; 斎藤彰
    エスペック地球環境研究・技術基金
    Aug. 2022 - Aug. 2023
  • 小型CO2センサー群による密閉密集の可視化
    01 May 2021
  • 協調給電による再生可能エネルギー指向自律分散グリッドの開発と実証
    横川慎二
    Principal investigator
    30 Jun. 2017 - 31 Mar. 2021
  • リスクモードとオンラインモニタリング技術高度化に着目した未然防止体系の新展開
    鈴木和幸
    01 Apr. 2015 - 31 Mar. 2020
  • Advanced Metallization Conference 2019 29th Asian Session研究会助成
    公益財団法人村田学術振興財団, 研究会助成
    09 Oct. 2019
  • リチウムイオン二次電池の余寿命予測とリユースのための2変量寿命分布解析の応用
    横川慎二
    Apr. 2014 - Mar. 2017
  • 機械学習・深層学習を用いたリチウムイオン二次電池の市場信頼性予測の研究
    横川慎二
    公益財団法人カシオ科学振興財団, 研究協賛, Principal investigator
    2016
  • Research and Development on Next-Generation Quality and Reliability Information System
    SUZUKI Kazuyuki; TANAKA Kenji; ITOH Makoto; YAMAMOTO Watalu; JIN Lu; YOKOYAMA Masahiro; TSUBAKI Hiroe; NAGATSUKA Hideki; YOKOGAWA Shinji
    Japan Society for the Promotion of Science, Grants-in-Aid for Scientific Research, The University of Electro-Communications, Grant-in-Aid for Scientific Research (A), Outline of Research Findings The purpose of this study is to create the standard manufacturing process for high quality and high reliability products, based on Next-Generation QRIS (Quality and Reliability Information System) combining and utilizing the knowledge of quality control, reliability engineering, and advanced information and communication technology. Throughout this study, we aim the following matters: ①To ensure reliability and safety by improving the accuracy of personalized risk communication to individual customer. ②To establish the prevention system for troubles related to quality and reliability, focused on hazard, failure mode, top event mode, and effect. ③To renovate reliability engineering with the trends of the information age., 22241038
    01 Apr. 2010 - 31 Mar. 2015

Industrial Property Rights

  • 発電量推定装置
    Patent right, 特願2022-056979, Date applied: 30 Mar. 2022
  • 給電制御システム
    Patent right, 市川晴久, 横川慎二, 川喜田祐介, 特願2017-214821, Date applied: 07 Nov. 2017, 特許第7038402号, Date issued: 10 Mar. 2022
  • 発電量推定装置
    Patent right, 特願2021-037410, Date applied: 09 Mar. 2021
  • 蓄電池管理システム、蓄電池情報サーバ、充放電制御装置及び蓄電池
    Patent right, 市川晴久, 川喜田祐介, 澤田賢治, 横川慎二, 特願2015-150389, Date applied: 30 Jul. 2015

Social Contribution Activities

  • 2023年度宇宙転用可能性部品の宇宙適用ハンドブック改訂検討会委員
    Advisor, JAXA, Others
    27 Sep. 2023 - 29 Feb. 2024
  • 技術支援 一般社団法人電子情報技術産業協会 半導体信頼性技術委員会 半導体信頼性用語集策定TF
    Advisor, 一般社団法人電子情報技術産業協会, 一般社団法人電子情報技術産業協会, civic_organization
    Jun. 2019
  • 地域支援等への参画 神奈川県立多摩高等学校SSH運営指導委員会委員
    Organizing member
    01 Apr. 2019
  • 技術支援 一般社団法人電子情報技術産業協会 半導体信頼性技術委員会 区間推定TF
    Advisor, 一般社団法人電子情報技術産業協会, 一般社団法人電子情報技術産業協会, civic_organization
    Dec. 2016 - Jun. 2018

Media Coverage

  • "エコなeスポーツイベント、「可搬式円筒形太陽光発電モジュール」を活用 調布市、NTT東日本ら"
    都政新報
    Dec. 2023
  • 重さ2kgの新たな太陽電池,都と共同で実証実験進む
    Other than myself, 月刊Smart House, 9月号32-33ページ, Paper
    Sep. 2023
  • 上釜美憂のコレが知りたい!
    Other than myself, テレビ愛知, 5時スタ, Media report
    Aug. 2023
  • キーデバイス
    Other than myself, 日刊工業新聞, 日刊工業新聞, 経営ひと言, Paper
    Jul. 2023
  • 東京都と電通大、都市型太陽電池で協定 発電量2倍に
    Other than myself, 日本経済新聞社, 日本経済新聞, Paper
    Apr. 2023
  • 壁面に円筒型太陽電池 電通大、都と実証
    Other than myself, 電気新聞, Paper
    Apr. 2023
  • For Future先端技術 壊れても取り替え容易
    Other than myself, 日刊工業新聞社, 日刊工業新聞, Paper
    Jan. 2023
  • イマナマ! リチウムイオン電池を含んだ製品のトラブルや安全利用についての研究内容
    中国放送, Media report
    Jul. 2022
  • ニュースウォッチ9 "スマホ熱中症"について
    NHK, Media report
    Jul. 2022
  • 進化する世界の中でも「在り」つづけるファニチャー
    CARBON STOCK FURNITURE(東京ガスコミュニケーションズ株式会社), Others
    Jul. 2022
  • 職場・新常態/電気通信大学 センサーでCO2“見える化”
    日刊工業新聞, Paper
    Feb. 2022
  • ジモト応援!東京つながるNews
    J:COMチャンネル, Media report, 横川慎二教授、澤田賢治准教授(i-パワードエネルギー・システム研究センター)、安達宏一准教授(先端ワイヤレスコミュニケーション研究センター)、榎木光治准教授(機械知能システム学専攻)、石垣陽特任准教授(情報学専攻)の学内ワクチン接種会場でのAI/IoT環境センサの実証実験について、J:COMチャンネル(地デジ11Ch)「ジモト応援!東京つながるNews」で紹介
    Aug. 2021
  • 「ながら充電」に注意 携帯市場と電通大がスマホのバッテリー劣化を防ぐ研究
    iTmedia mobile, Others
    Apr. 2021
  • News23 石垣陽特任准教授(情報学専攻)がCO2濃度の可視化ついて解説し、本学の入学式準備での実験や、調布駅前商店街での実証例を紹介
    TBS, Media report
    Apr. 2021
  • イット!「ながら充電」でバッテリーの劣化が加速 「充電しながらゲーム」で8.9度の温度上昇も
    フジテレビ, Media report
    Apr. 2021
  • スッキリ スマホバッテリーの劣化原因などについて紹介
    日本テレビ, Media report
    Apr. 2021
  • スマホバッテリーの劣化や発熱について解説
    日刊ゲンダイ, Paper
    Apr. 2021
  • ""全学データをAI解析、認知症患者の問題行動予測 電通大が検証"" 全学の活動データをIoT(モノのインターネット)で集め、人口知能(AI)で絞り込んで解析する「IoT・AIキャンパス」プロジェクトについて
    日刊工業新聞, Paper
    Apr. 2021
  • ""新型コロナ 調布方式 医師巡回接種始まる"" 調布市が新型コロナウイルスワクチンの集団接種会場に、本学が開発したCO2センサーを導入
    東京新聞, Paper
    Apr. 2021

Academic Contribution Activities

  • IEEE Reliability Society Japan Joint Chapter
    Academic society etc, Planning etc, IEEE Reliability Society Japan Joint Chapter, 08 Dec. 2023 - Present
  • IEEE International Reliabiliby Physics Symposium, Program Committee
    Competition etc, Planning etc, IEEE, 14 Apr. 2024 - 18 Apr. 2024
  • IEEE Electron Devices Technology and Manufacturing Conference
    Competition etc, Planning etc, IEEE, 03 Mar. 2024 - 06 Mar. 2024
  • 日本信頼性学会第36回秋季シンポジウム
    Academic society etc, Planning etc, 日本信頼性学会, 02 Nov. 2023 - 02 Nov. 2023
  • Advanced Metallization Conference Plus 2023
    Competition etc, Planning etc, 応用物理学会, 11 Oct. 2023 - 13 Oct. 2023
  • 日本信頼性学会第31回春季シンポジウム
    Academic society etc, Planning etc, 日本信頼性学会, 01 Jun. 2023 - 01 Jun. 2023
  • IEEE International Reliabiliby Physics Symposium, Program Committee
    Competition etc, Peer review, IEEE, 26 Mar. 2023 - 30 Mar. 2023
  • 第13回横幹連合コンファレンス
    Academic society etc, Planning etc, 17 Dec. 2022
  • 日本信頼性学会第35回秋季シンポジウム
    Competition etc, Planning etc, 日本信頼性学会, 21 Nov. 2022
  • IEEE Reliability Society Japan Joint Chapter Seminar
    Academic society etc, Planning etc, IEEE Reliability Society Japan Joint Chapter, 26 Oct. 2022
  • Advanced Metallization Conference Plus 2022
    Competition etc, Others, 12 Oct. 2022 - 14 Oct. 2022
  • Reliability Engineering & System Safety
    Peer review etc, Peer review, Mar. 2022