Spin-dependent electron transport through Si-based magnetic tunnel junctions

• Project/Area Number: 20H02199
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 21060:Electron device and electronic equipment-related
• Research Institution: The University of Tokyo
• Principal Investigator: Nakane Ryosho 東京大学, 大学院工学系研究科(工学部), 特任准教授 (50422332)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Project Status: Completed (Fiscal Year 2022)
• Budget Amount: ¥17,680,000 (Direct Cost: ¥13,600,000、Indirect Cost: ¥4,080,000); Fiscal Year 2022: ¥2,600,000 (Direct Cost: ¥2,000,000、Indirect Cost: ¥600,000); Fiscal Year 2021: ¥5,200,000 (Direct Cost: ¥4,000,000、Indirect Cost: ¥1,200,000); Fiscal Year 2020: ¥9,880,000 (Direct Cost: ¥7,600,000、Indirect Cost: ¥2,280,000)
• Keywords: 電子デバイス / 電子スピン伝導物理 / スピントロニクス / 半導体スピントロニクス / シリコンデバイス

Outline of Research at the Start

シリコン電界効果型トランジスタに伝導電子スピンの効果を取り入れたシリコンベーススピントランジスタの磁気抵抗効果を高めるために、低抵抗かつ高効率なスピン注入源となる強磁性トンネル接合を創製する。その目的を達成するために、スピン依存トンネル現象を定量的に解析して物理を明らかにするとともに、材料と作製条件の探索をおこない作製技術の開発をおこなう。トンネル障壁層の材料として、Siを酸窒化したSiONとエピタキシャルフェライト薄膜を用いて研究を遂行する。

Outline of Final Research Achievements

This project studied physics on spin-dependent electron transport via Si-based magnetic tunnel junctions as well as via Si inversion channels. Original theories were establised and used for the analyses of experimental spin-transport signals. The detailed analyses clarified physics that is very useful knowledge for high-performance Si-based spin transistors.

Academic Significance and Societal Importance of the Research Achievements

次世代IoT社会の実現に極めて有用なデバイス「シリコンベーススピントランジスタ」を実用に近づけるために重要な知見を多数明らかとした。また、オリジナルな物理モデルを確立して電子スピン伝導物理の詳細を定量的に解明した。この学術の深化は、該当研究分野の進展に大きく貢献することが期待できる。

Research Products

• [Journal Article] Electron Spin Transport in a Metal-Oxide-Semiconductor Si Two-Dimensional Inversion Channel: Effect of Hydrogen Annealing on Spin-Scattering Mechanism and Spin Lifetime (2022)
  • Author(s): Shoichi Sato, Masaaki Tanaka, and Ryosho Nakane
  • Journal Title: Physical Review Applied Volume: 18 Issue: 6
  • DOI: 10.1103/physrevapplied.18.064071
  • Peer Reviewed / Open Access
• [Journal Article] Spin transport in Si-based spin metal-oxide-semiconductor field-effect transistors: Spin drift effect in the inversion channel and spin relaxation in the n+－Si source/drain regions (2020)
  • Author(s): S. Sato, M. Tanaka, and R. Nakane
  • Journal Title: Physical Review B Volume: 102 Issue: 3 Pages: 035305-035305
  • DOI: 10.1103/physrevb.102.035305
  • Peer Reviewed
• [Journal Article] Enhancement of Room-Temperature Effective Spin Diffusion Length in a Si-Based Spin MOSFET With an Inversion Channel (2020)
  • Author(s): R. Nakane, S. Sato, and M. Tanaka
  • Journal Title: IEEE Journal of the Electron Devices Society Volume: 8 Pages: 807-812
  • DOI: 10.1109/jeds.2020.2993705
  • Peer Reviewed / Open Access
• [Presentation] Spin polarization and magnetoresistance in a back-gated spin MOSFET structure with Fe/Mg/MgO/SiOx/n+-Si junctions (2023)
  • Author(s): Shoichi Sato, Masaaki Tanaka and Ryosho Nakane
  • Organizer: 第70回応用物理学会春季学術講演会
• [Presentation] Generation of spin-polarized electrons in n + -Si by spin injection through a ferromagnetic tunnel junction: Role of the band diagram (2022)
  • Author(s): Baisen Yu, Shoichi Sato, Masaaki Tanaka, and Ryosho Nakane
  • Organizer: 2022 International Conference on Solid State Devices and Materials
  • Int'l Joint Research
• [Presentation] Electron spin polarization in a n+-Si channel: Analysis with the band diagram in ferromagnetic Fe/Mg/amorphous-MgO/SiO X /n+-Si(001) tunnel junctions (2022)
  • Author(s): Baisen Yu, Shoichi Sato, Masaaki Tanaka and Ryosho Nakane
  • Organizer: 第69回応用物理学会春季学術講演会
• [Presentation] 低接合抵抗を持つFe/Mg/SiN/n+-Si(001)磁性トンネル接合の作製とSiへのスピン注入 (2022)
  • Author(s): 赤木巌、佐藤彰一、田中雅明、中根了昌
  • Organizer: 第83回応用物理学会秋季学術講演会
• [Presentation] Effect of forming gas annealing on the enhancement of the electron spin lifetime in the inversion channel of Si-based spin MOSFETs (2020)
  • Author(s): S. Sato, S. Okamoto, M. Tanaka, and R. Nakane
  • Organizer: 第68回応用物理学会春季学術講演会
• [Presentation] Siへのスピン注入におけるトンネルスピン分極率の温度依存性の解析 (2020)
  • Author(s): 岡本祥太、佐藤彰一、田中 雅明、中根了昌
  • Organizer: 第68回応用物理学会春季学術講演会
• [Presentation] Spin-flip Mechanism in a Si Inversion Layer of Spin MOSFETs (2020)
  • Author(s): R. Nakane, S. Sato, S. Okamoto, and M, Tanaka
  • Organizer: The 78th Device Research Conference (DRC)
  • Int'l Joint Research
• [Presentation] , Spin transport in Si-based spin metal-oxide-semiconductor field-effect transistors: Spin drift effect in the inversion channel and spin relaxation in the n+-Si source/drain regions (2020)
  • Author(s): S. Sato, S. Okamoto, M. Tanaka, and R. Nakane
  • Organizer: 第81回応用物理学会秋季学術講演会
• [Presentation] シリコンベーススピン電界効果型トランジスタのデバイス物理 (2020)
  • Author(s): 中根了昌、佐藤彰一、田中雅明
  • Organizer: スピントロニクス学術研究基盤と連携ネットワーク拠点 2020 年度（令和２年度）年次報告会
  • Invited