Improving the reliability of GaN HEMTs using MMC structures and free-standing GaN substrates

• Project/Area Number: 15K06013
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Electron device/Electronic equipment
• Research Institution: University of Fukui
• Principal Investigator: Asubar Joel 福井大学, テニュアトラック推進本部, 講師 (10574220)
• Co-Investigator(Kenkyū-buntansha): 葛原 正明 福井大学, 学術研究院工学系部門, 教授 (20377469)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Project Status: Completed (Fiscal Year 2017)
• Budget Amount: ¥4,940,000 (Direct Cost: ¥3,800,000、Indirect Cost: ¥1,140,000); Fiscal Year 2017: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2016: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000); Fiscal Year 2015: ¥3,120,000 (Direct Cost: ¥2,400,000、Indirect Cost: ¥720,000)
• Keywords: Gallium nitride / current collapse / power device / semiconductor / AlGaN/GaN HEMT / AlGaN/GaN / HEMT / Current Collapse / Breakdown Voltage / Stability / AlGaN-GaN / 窒化物半導体 / 電流コラプス / MIS / GaN / パワーデバイス / 自己発熱 / 多重台形チャネル / 酸素プラズマ処理

Outline of Final Research Achievements

Our aim is to achieve improved stability and reliability of AlGaN/GaN HEMTs using structure-based strategies such as using the so-called multi-mesa-channel. Investigations have revealed that the MMC HEMT is highly resistant to current collapse and other instabilities, making it a leading power electronics prospect. We also investigated other current collapse approaches that can be used in conjunction with MMC in the future such as high pressure water vapor annealing, oxygen plasma treatment, field-plate and metal-insulator-semiconductor structures.

Research Products

• [Journal Article] Correlation of AlGaN/GaN HEMTs electroluminescence characteristics with current collapse (2018)
  • Author(s): S. Ohi, T. Yamazaki, J. T. Asubar, H. Tokuda, and M. Kuzuhara
  • Journal Title: Appl. Phys. Express Volume: 11 Issue: 2 Pages: 024101-024101
  • DOI: 10.7567/apex.11.024101
  • Peer Reviewed
• [Journal Article] Impact of rounded electrode corners on breakdown characteristics of AlGaN/GaN high-electron mobility transistors (2018)
  • Author(s): Taisei Yamazaki, Joel T. Asubar, Hirokuni Tokuda, and Masaaki Kuzuhara
  • Journal Title: Applied Physics Express Volume: 11 Issue: 5 Pages: 0541021-0541025
  • DOI: 10.7567/apex.11.054102
  • NAID: 210000136205
  • Peer Reviewed
• [Journal Article] Analytical derivation of interface state density from sub-threshold swing in AlGaN/GaN metal-insulator-semiconductor high-electron-mobility transistors (2017)
  • Author(s): H. Tokuda, J. T. Asubar, and M. Kuzuhara
  • Journal Title: Jpn. J. Appl. Phys. Volume: 56 Issue: 10 Pages: 104101-104101
  • DOI: 10.7567/jjap.56.104101
  • NAID: 210000148328
  • Peer Reviewed
• [Journal Article] AlGaN/GaN MIS-HEMTs with high on/off current ratio of over 5 × 1010 achieved by ozone pretreatment and using ozone oxidant for Al2O3 gate insulator (2016)
  • Author(s): H. Tokuda, J. T. Asubar, and M. Kuzuhara
  • Journal Title: Japanese Journal of Applied Physics Volume: 55 Issue: 12 Pages: 120305-120305
  • DOI: 10.7567/jjap.55.120305
  • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Highly-stable and low-state-density Al2O3/GaN interfaces using epitaxial n-GaN layers grown on free-standing GaN substrates (2016)
  • Author(s): S. Kaneki, J. Ohira, S. Toiya, Z. Yatabe, J. T. Asubar and T. Hashizume
  • Journal Title: Appl. Phys. Lett. Volume: 109 Issue: 16
  • DOI: 10.1063/1.4965296
  • NAID: 120006360059
  • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Z. Yatabe, J. T. Asubar, and T. Hashizume (2016)
  • Author(s): Insulated gate and surface passivation structures for GaN-based power transistors
  • Journal Title: Journal of Physics D: Applied Physics Volume: 49 Issue: 39 Pages: 1-19
  • DOI: 10.1088/0022-3727/49/39/393001
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] Pushing the GaN HEMT towards its theoretical limit (2016)
  • Author(s): J. T. Asubar, J. Ng, H. Tokuda, M, Kuzuhara
  • Journal Title: Compound Semiconductor Magazine Volume: 22 Pages: 26-31
  • Open Access / Int'l Joint Research
• [Journal Article] AlGaN/GaN high-electron-mobility transistor technology for high-voltage and low-on-resistance operation (2016)
  • Author(s): M. Kuzuhara, J. T. Asubar, and H. Tokuda
  • Journal Title: Japanese Journal of Applied Physics Volume: 55 Issue: 7 Pages: 0701011-12
  • DOI: 10.7567/jjap.55.070101
  • NAID: 210000146739
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Highly Reduced Current Collapse in AlGaN/GaN HEMTs by Combined Application of Oxygen Plasma Treatment and Field-plate Structures (2016)
  • Author(s): J. T. Asubar, S. Yoshida, H. Tokuda, and M. Kuzuhara
  • Journal Title: Japanese Journal of Applied Physics Volume: 55 Issue: 4S Pages: 04EG07-04EG07
  • DOI: 10.7567/jjap.55.04eg07
  • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Impact of oxygen plasma treatment on the dynamic on-resistance of AlGaN/GaN high-electron-mobility (2015)
  • Author(s): Joel T. Asubar, Yoshiki Sakaida, Satoshi Yoshidai, Zenji Yatabe, Hirokuni Tokuda, Tamotsu Hashizume, Masaaki Kuzuhara
  • Journal Title: Applied Physics Express Volume: 8 Issue: 11 Pages: 1110011-4
  • DOI: 10.7567/apex.8.111001
  • Peer Reviewed / Int'l Joint Research / Acknowledgement Compliant
• [Journal Article] Current Collapse Reduction in AlGaN/GaN HEMTs by High-Pressure Water Vapor Annealing (2015)
  • Author(s): Joel T. Asubar, Yohei Kobayashi, Koji Yoshitsugu, Zenji Yatabe, Hirokuni Tokuda, Masahiro Horita; Yukiharu Uraoka, Tamotsu Hashizume, Masaaki Kuzuhara
  • Journal Title: IEEE Transactions on Electron Devices Volume: 62 Issue: 8 Pages: 2423-2428
  • DOI: 10.1109/ted.2015.2440442
  • Peer Reviewed / Int'l Joint Research
• [Presentation] Characterization of AlGaN/GaN recessed MIS-HEMTs using sputtered SiN as gate dielectric (2018)
  • Author(s): Wataru Gamachi, Joel Asubar, Hirokuni Tokuda, and Masaaki Kuzuhara
  • Organizer: 2018-nendo Shunki Dai-65-kai Ouyou Butsuri Gakku Kankei Rengou Koenkai (Japan Society of Applied Physics 65th Spring Meeting)
• [Presentation] Effective Suppression of Current Collapse in AlGaN/GaN HEMTs (2017)
  • Author(s): Joel T. Asubar, Hirokuni Tokuda, and Masaaki Kuzuhara
  • Organizer: 35th Samahang Pisika ng Pilipinas Physics Conference (SPP 2017)
  • Int'l Joint Research / Invited
• [Presentation] Investigation of Dynamic On-Resistance of Multi-Mesa-Channel AlGaN/GaN HEMTs (2017)
  • Author(s): Joel T. Asubar, Hirokuni Tokuda, Tamotsu Hashizume, and Masaaki Kuzuhara
  • Organizer: 6th International Symposium on Organic and Inorganic Electronic Materials and Related Nanotechnologies (EM-NANO 2017)
  • Int'l Joint Research
• [Presentation] Effect of Substrate Thermal Resistivity on Breakdown Voltage of AlGaN/GaN HEMTs (2017)
  • Author(s): Taisei Yamazaki, Joel T. Asubar, Hirokuni Tokuda, and Masaaki Kuzuhara
  • Organizer: 6th International Symposium on Organic and Inorganic Electronic Materials and Related Nanotechnologies (EM-NANO 2017)
  • Int'l Joint Research
• [Presentation] Enhancement-Mode AlGaN/GaN MOS-HEMTs with Recessed-Gate Structures Exhibiting High Threshold Voltage (2017)
  • Author(s): W. Gamachi, K. Ishii, J. T. Asubar, H. Tokuda, and M. Kuzuhara
  • Organizer: 6th International Symposium on Organic and Inorganic Electronic Materials and Related Nanotechnologies (EM-NANO 2017)
  • Int'l Joint Research
• [Presentation] Effect of Reverse Bias Annealing on the Properties of AlGaN/GaN MIS-HEMTs with Recessed-gate Structure (2017)
  • Author(s): W. Gamachi, K. Ishii, J. T. Asubar, H. Tokuda, and M. Kuzuhara
  • Organizer: 2017 International Meeting for Future of Electron Devices Kansai (IMFEDK 2017)
  • Int'l Joint Research
• [Presentation] Effects of Electronic States at Insulator/AlGaN Interfaces on Threshold Voltage Instability of Al2O3/AlGaN/GaN Structures (2016)
  • Author(s): Z. Yatabe, J. T. Asubar, Y. Nakamura, and T. Hashizume
  • Organizer: 2016 International Conference on Solid State Devices and Materials (SSDM 2016)
  • Place of Presentation: Tsukuba, Japan
  • Year and Date: 2016-09-26
  • Int'l Joint Research
• [Presentation] 24.Characterization of Insulators/(Al)GaN Interfaces for Improved Insulated Gate and Surface Passivation Structures of GaN-based Transistors (2016)
  • Author(s): Z. Yatabe, Y. Hori, W.C. Ma, J. T. Asubar, M. Akazawa, T. Sato, and T. Hashizume
  • Organizer: 第77回応用物理学会秋季学術講演会
  • Place of Presentation: Toki Messe, Niigata, Japan
  • Year and Date: 2016-09-13
  • Invited
• [Presentation] Improved linearity, stability, and thermal performance of multi-mesa-channel AlGaN/GaN HEMTs (2016)
  • Author(s): J. T. Asubar, H. Tokuda, M, Kuzuhara, Z. Yatabe, K. Nishiguchi, and T. Hashizume
  • Organizer: 34th Samahang Pisika ng Pilipinas Physics Conference
  • Place of Presentation: University of the Philippines Visayas, Iloilo, Philippines
  • Year and Date: 2016-08-18
  • Invited
• [Presentation] High on/off ratio AlGaN/GaN MIS-HEMTs with ALD deposited Al2O3 gate dielectric using ozone as an oxidant (2016)
  • Author(s): H. Tokuda, J. T. Asubar, M. Kuzuhara
  • Organizer: 2016 Asia-Pacific Workshop on Fundamentals and Applications of Advanced Semiconductor Devices
  • Place of Presentation: Hakodate, Japan
  • Year and Date: 2016-07-04
  • Int'l Joint Research
• [Presentation] Impact of Drain Electrode Shape Irregularities on Breakdown Voltage of AlGaN/GaN HEMTs (2016)
  • Author(s): S. Ohi, S. Makino, T. Yamazaki, H. Tokuda, J. T. Asubar, and M. Kuzuhara
  • Organizer: 2016 Compound Semiconductor Week
  • Place of Presentation: Toyama International Conference Center, Toyama, Japan
  • Year and Date: 2016-06-26
  • Int'l Joint Research
• [Presentation] Breakdown Voltages of AlGaN/GaN HEMTs Breakdown degradation of AlGaN/GaN HEMTs with multi-finger gate patterns (2016)
  • Author(s): S. Makino, S. Ohi, J. T. Asubar, H. Tokuda, and M. Kuzuhara
  • Organizer: 2016 International Meeting for Future of Electron Devices Kansai (IMFEDK 2016)
  • Place of Presentation: Ryukoku University Avanti Kyoto Hall, Kyoto, Japan
  • Year and Date: 2016-06-23
  • Int'l Joint Research
• [Presentation] AlGaN/GaN HEMTs on Free-standing GaN Substrates with Breakdown Voltage of 5 kV and Effective Lateral Critical Field of 1 MV/cm (2016)
  • Author(s): J. H. Ng, J. T. Asubar, H. Tokuda, and M. Kuzuhara
  • Organizer: 2016 International Conference on Compound Semiconductor Manufacturing Technology (CS Mantech 2016)
  • Place of Presentation: Miami, Florida, USA
  • Year and Date: 2016-06-16
  • Int'l Joint Research
• [Presentation] Effect of Metal Electrode Shape Irregularities on AlGaN/GaN HEMTs Breakdown Voltage Revealed by Electroluminescence (2016)
  • Author(s): S. Makino, T. Yamazaki, S. Ohi, H. Tokuda, J. T. Asubar, and M. Kuzuhara
  • Organizer: 40th Workshop on Compound Semiconductor Devices and Integrated Circuits (WOCSDICE) 2016
  • Place of Presentation: Aveiro, Portugal
  • Year and Date: 2016-06-06
  • Int'l Joint Research
• [Presentation] Highly Reduced Current Collapse in AlGaN/GaN HEMTs by Combined Application of Oxygen Plasma Treatment and Field-plate Structures (2015)
  • Author(s): Joel T. Asubar, Satoshi Yoshida, Hirokuni Tokuda, and Masaaki Kuzuhara
  • Organizer: 2015 International Conference on Solid State Devices and Materials (SSDM 2015)
  • Place of Presentation: Sapporo, Hokkaido, Japan
  • Year and Date: 2015-09-27
• [Presentation] Comparative study of oxygen plasma treatment and GaN cap layer effects on the current collapse of AlGaN/GaN HEMTs (2015)
  • Author(s): Joel T. Asubar, Yoshiki Sakaida, Satoshi Yoshida, Zenji Yatabe, Hirokuni Tokuda, Tamotsu Hashizume, and Masaaki Kuzuhara
  • Organizer: 11th Topical Workshop on Heterostructure Microelectronics (TWHM 2015)
  • Place of Presentation: Takayama, Japan
  • Year and Date: 2015-08-23
• [Presentation] Electrical Characterization of stepped AlGaN/GaN Heterostructures (2015)
  • Author(s): Shintaro Kodama, Joel T. Asubar, Hirokuni Tokuda, S, Nakazawa, M. Ishida, T. Ueda, and Masaaki Kuzuhara
  • Organizer: The 39th Workshop on Compound Semiconductor Devices and Integrated Circuits
  • Place of Presentation: Smolenice castle, Slovakia
  • Year and Date: 2015-06-08
• [Presentation] Suppressed Current Collapse in High Pressure Water Vapor Annealed AlGaN/GaN HEMTs (2015)
  • Author(s): Yohei Kobayashi, Joel T. Asubar, Koji Yoshitsugu, Hirokuni Tokuda, and Masahiro Horita, Yukiharu Uraoka, and Masaaki Kuzuhara
  • Organizer: 2016 International Conference on Compound Semiconductor Manufacturing Technology (CS MANTECH 2015)
  • Place of Presentation: Scottsdale, Arizona, USA
  • Year and Date: 2015-05-18
• [Presentation] Correlation between Electroluminescence and Current Collapse in AlGaN/GaN HEMTs (2015)
  • Author(s): Shintaro Ohi, Yoshiki Sakaida, Joel T. Asubar, Hirokuni Tokuda, and Masaaki Kuzuhara
  • Organizer: 2016 International Conference on Compound Semiconductor Manufacturing Technology (CS MANTECH 2015)
  • Place of Presentation: Scottsdale, Arizona, USA
  • Year and Date: 2015-05-18
• [Remarks]
  • URL: https://www.researchgate.net/profile/Joel_Asubar
• [Remarks]
  • URL: https://scholar.google.co.jp/citations?user=1NlRAggAAAAJ&hl=en&oi=sra