Production of a-Si from supercooled liquid Si

• Project/Area Number: 26709057
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Partial Multi-year Fund
• Research Field: Metal making/Resorce production engineering
• Research Institution: Tohoku University (2015-2016); Japan Aerospace Exploration Agency (2014)
• Principal Investigator: OKADA JUNPEI 東北大学, 金属材料研究所, 准教授 (90373282)
• Project Period (FY): 2014-04-01 – 2017-03-31
• Project Status: Completed (Fiscal Year 2016)
• Budget Amount: ¥24,570,000 (Direct Cost: ¥18,900,000、Indirect Cost: ¥5,670,000); Fiscal Year 2016: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000); Fiscal Year 2015: ¥2,990,000 (Direct Cost: ¥2,300,000、Indirect Cost: ¥690,000); Fiscal Year 2014: ¥19,890,000 (Direct Cost: ¥15,300,000、Indirect Cost: ¥4,590,000)
• Keywords: アモルファス / シリコン / 過冷却液体 / 静電浮遊法 / 急冷 / 液体急冷 / 静電浮遊 / 浮遊法 / 急冷凍結

Outline of Final Research Achievements

Amorphous (a-) silicon (Si) is an important semiconductor used for thin film transistors and solar panels. In 1975, Spear et al. demonstrated that thin films of a-Si deposited by Plasma-Enhanced Chemical Vapor Deposition (PECVD) from silane (SiH4) are useful for semiconductor devices, which constitutes a breakthrough for a-Si applications1. On the other hand, it has long been challenged to obtain a “bulk” a-Si from liquid (l-) Si. However, all attempts have failed so far. In this research project, we tried to produce bulk a-Si directly from supercooled l-Si. Combining an electrostatic levitator with a quenching system, we quenched supercooled l-Si at 300 K below the melting temperature to obtain bulk a-Si.

Research Products

• [Int'l Joint Research] City University of Hong Kong Kowloon(China)
• [Int'l Joint Research] Northeastern University(米国)
• [Int'l Joint Research] City University of Hong Kong Kowloon(中国)
• [Journal Article] Visualizing the Mixed Bonding Properties of Liquid Boron with High-Resolution X-Ray Compton Scattering (2015)
  • Author(s): J. T. Okada, P.H.-L. Sit, Y. Watanabe, B. Barbiellini, T. Ishikawa, Y.J. Wang, M. Itou, Y. Sakurai, A. Bansil, R. Ishikawa, M. Hamaishi, P.-F. Paradis, K. Kimura, T. Ishikawa, and S. Nanao
  • Journal Title: Physical Review Letters Volume: 114 Issue: 17 Pages: 177401-177401
  • DOI: 10.1103/physrevlett.114.177401
  • Peer Reviewed / Int'l Joint Research
• [Presentation] Ｐｈｙｓｉｃａｌ Ｐｒｏｐｅｒｔｉｅｓ ｏｆ Ｌｉｑｕｉｄ Ｂｏｒｏｎ (2017)
  • Author(s): Ｊｕｎｐｅｉ ＯＫＡＤＡ
  • Organizer: Ｍａｔｅｒｉａｌｓ Ｓｃｉｅｎｅ ＆ Ｔｅｃｈｎｏｌｏｇｙ ２０１７
  • Place of Presentation: Ｐｉｔｔｓｂｕｒｇｈ， ＵＳＡ
  • Year and Date: 2017-10-08
  • Int'l Joint Research / Invited
• [Presentation] Ｔｈｅｒｍｏｐｈｙｓｉｃａｌ Ｐｒｏｐｅｒｔｙ ｏｆ Ｓｕｐｅｒｃｏｏｌｅｄ－ｌｉｑｕｉｄ Ｓｉｌｉｃｏｎ (2017)
  • Author(s): Ｊｕｎｐｅｉ ＯＫＡＤＡ
  • Organizer: ＩＳＴＳ２０１７
  • Place of Presentation: Ｍａｔｓｕｙａｍａ， ＪＡＰＡＮ
  • Year and Date: 2017-06-05
  • Int'l Joint Research
• [Presentation] Ｔｈｅｒｍｏｐｈｙｓｉｃａｌ Ｐｒｏｐｅｒｔｉｅｓ ｏｆ Ｓｕｐｅｒｃｏｏｌｅｄ－ｌｉｑｕｉｄ Ｓｉｌｉｃｏｎ (2016)
  • Author(s): Ｊｕｎｐｅｉ ＯＫＡＤＡ
  • Organizer: Ｔｈｅ １８ｔｈ Ｉｎｔｅｒｎａｔｉｏｎａｌ Ｃｏｎｆｅｒｅｎｃｅ ｏｎ Ｃｒｙｓｔａｌ Ｇｒｏｗｔｈ ａｎｄ Ｅｐｉｔａｘｙ
  • Place of Presentation: Ｎａｇｏｙａ， ＪＡＰＡＮ
  • Year and Date: 2016-08-07
  • Int'l Joint Research
• [Presentation] 超高温融体の物性ーホウ素は融けても半導体 (2016)
  • Author(s): 岡田純平
  • Organizer: 日本化学会第96春季年会
  • Place of Presentation: 同志社大学
  • Year and Date: 2016-03-26
  • Invited
• [Presentation] Bonding Characteristics of High Temperature Liquids Studies by Elsctrostatic Levitator (2015)
  • Author(s): J.Okada, P. Sit, T. Ishikawa, Y. Watanabe, B. Barbiellini, A. Bansil, M. Itou, Y. Sakurai, K. Kimura, S. Nanao
  • Organizer: ISPS-6/ITTW2015
  • Place of Presentation: Kyoto, Japan
  • Year and Date: 2015-09-16
  • Int'l Joint Research
• [Presentation] 静電浮遊法を用いた高温融体の物性研究と準安定相探索 (2015)
  • Author(s): 岡田純平
  • Organizer: 日本セラミックス協会年会 サテライトプログラム
  • Place of Presentation: 岡山大学
  • Year and Date: 2015-03-18
  • Invited