Creation of high-performance Si-based spin transistors and development of their spin calculation functions

• Project/Area Number: 21H04561
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Medium-sized Section 21:Electrical and electronic engineering and related fields
• Research Institution: Kyoto University
• Principal Investigator: Shiraishi Masashi 京都大学, 工学研究科, 教授 (30397682)
• Project Period (FY): 2021-04-05 – 2024-03-31
• Project Status: Completed (Fiscal Year 2023)
• Budget Amount: ¥36,530,000 (Direct Cost: ¥28,100,000、Indirect Cost: ¥8,430,000); Fiscal Year 2023: ¥6,890,000 (Direct Cost: ¥5,300,000、Indirect Cost: ¥1,590,000); Fiscal Year 2022: ¥8,190,000 (Direct Cost: ¥6,300,000、Indirect Cost: ¥1,890,000); Fiscal Year 2021: ¥21,450,000 (Direct Cost: ¥16,500,000、Indirect Cost: ¥4,950,000)
• Keywords: スピントランジスタ / シリコン / スピン演算 / スピン流

Outline of Research at the Start

本提案では3年間の研究期間で、(i) 再構成可能論理回路創出に必要なスピン素子の磁気抵抗比100%を、従来にはなかったSiスピン素子の縦型化という発想と現在進行中の新規な素子作製技術の確立で、(ii)基盤研究(S)で実証に成功したスピン流XOR論理演算素子の発展による集積化が容易で切り替え可能な新規論理演算の実現で、それぞれクリアし、3年後にSiスピントロニクスを応用に資するレベルに確実に到達させることを目標とする。

Outline of Final Research Achievements

I have driven the research project by setting the following targets: (1)Realization of MR ratio of 100% using SI spin FET and creation of spin-based logic circuit using it, and (2)Realization of Magnetic Logic Gate(MLG) using Si spin FET. As for (1) I established approaches to circumvent the obstacles for realizing the MR ratio of 100%, (a)parasitic resistance problem and (b) the Schottky barrier problem, although the MR ratio of 100% was not unfortunately achieved. As for (2), I realized spin-based logic system and demonstrated calculations such as "NAND" and "OR" by using Si spin FETs.

Academic Significance and Societal Importance of the Research Achievements

低消費エネルギー情報演算のキーテクノロジーの１つであるスピン演算の視点から、毒性がなくユビキタス材料であるシリコンを用いたスピン演算を実現し、将来的な応用に向けた基盤技術を構築でいた点に大きな学術的・社会的意義を有する。

Research Products

• [Journal Article] Precise estimation of spin drift velocity and spin mobility in the absence of synthetic Rashba spin-orbit field in a Si metal-oxide-semiconductor (2023)
  • Author(s): H. Inoue, H. Koike, R. Ohshima, Y. Ando and M. Shiraishi
  • Journal Title: Physical Review B Volume: 108 Issue: 21 Pages: 214414-214414
  • DOI: 10.1103/physrevb.108.214414
  • Peer Reviewed
• [Journal Article] Realization of efficient tuning of the Fermi level in iron-based ferrimagnetic alloys (2022)
  • Author(s): N. Yamashita, E. Shigematsu, S. Honda, R. Ohshima, M. Shiraishi, and Y. Ando
  • Journal Title: Physical Review Materials Volume: 6 Pages: 104405-104405
  • Peer Reviewed
• [Presentation] 人工Rashba効果を考慮したシリコン中のスピンドリフト速度の定量的評価 (2023)
  • Author(s): 白石誠司, 井上元, 大島諒, 安藤裕一郎, 小池勇人
  • Organizer: 日本物理学会2024年春季大会
• [Presentation] Estimation of spin drift velocity and spin mobility in the absence of effective magnetic field due to Rashba-type SOI in n-type silicon spin MOSFET (2023)
  • Author(s): 井上元, 小池勇人, 大島諒, 安藤裕一郎,白石誠司
  • Organizer: 第84回応用物理学会秋季学術講演会
• [Presentation] Estimation of spin drift velocity considering effective magnetic field due to Rashba SOI in silicon spin MOSFET (2022)
  • Author(s): H. Inoue, M. Shiraishi, Y. Ando, R. Ohshima, E. Shigematsu, H. Koike
  • Organizer: 第83回応用物理学会秋季講演会