Removal of phosphorus and boron from molten silicon

• Project/Area Number: 21246115
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Metal making engineering
• Research Institution: The University of Tokyo
• Principal Investigator: MAEDA Masafumi 東京大学, 生産技術研究所, 教授 (70143386)
• Co-Investigator(Kenkyū-buntansha): OKABE Toru 東京大学, 生産技術研究所, 教授 (00280884) ; NAGAI Takashi 千葉工業大学, 工学部, 准教授 (40533633) ; OKURA Takahiko 東京大学, 生産技術研究所, 特任教授 (00400523) ; SASAKI Hideaki 東京大学, 生産技術研究所, 特任助教 (10581746)
• Project Period (FY): 2009 – 2011
• Project Status: Completed (Fiscal Year 2011)
• Budget Amount: ¥45,240,000 (Direct Cost: ¥34,800,000、Indirect Cost: ¥10,440,000); Fiscal Year 2011: ¥8,970,000 (Direct Cost: ¥6,900,000、Indirect Cost: ¥2,070,000); Fiscal Year 2010: ¥16,120,000 (Direct Cost: ¥12,400,000、Indirect Cost: ¥3,720,000); Fiscal Year 2009: ¥20,150,000 (Direct Cost: ¥15,500,000、Indirect Cost: ¥4,650,000)
• Keywords: 高純度化 / 太陽電池 / シリコン

Research Abstract

A process to remove phosphorus and boron from molten silicon was studied in order to produce solar-grade silicon at lower energy cost. Oxygen and water vapor were injected into silicon melted with electron beam under high vacuum. Evaporative removal of phosphorus was enhanced by injection of the reactive gases, and evaporation of oxidized boron was also indicated. The mechanism of the reactions was studied by development of a double Knudsen cell mass spectrometer equipped with a gas-injection apparatus. Evaporated species from Si-P alloys and boron were identified and evaluated quantitatively.

Research Products

• [Journal Article] Removal Rate of Phosphorus from Molten Silicon (2011)
  • Author(s): T. Kemmotsu, T. Nagai and M. Maeda;
  • Journal Title: High Temperature Materials and Processes Volume: Vol.1-2 Issue: 1-2 Pages: 17-22
  • DOI: 10.1515/htmp.2011.002
  • Peer Reviewed
• [Journal Article] Removal Rate of Phosphorus from Molten Silicon (2011)
  • Author(s): T.Kemmotsu, T.Nagai, M.Maeda
  • Journal Title: High Temperature Materials and Processes Volume: 1-2 Pages: 17-22
  • Peer Reviewed
• [Presentation] シリコンからの脱リンのための熱力学 (2013)
  • Author(s): 永井崇, 山下智司, 前田正史;
  • Organizer: 質量分析学会高温質量分析部会
  • Place of Presentation: 東京
  • Year and Date: 2013-03-11
• [Presentation] Thermodynamic Study for Removal of Phosphorus from Molten Silicon (2012)
  • Author(s): T. Nagai and M. Maeda
  • Organizer: The 7th Workshop on Reactive Metal Processing
  • Place of Presentation: Cambridge, MA, USA.
  • Year and Date: 2012-03-16
• [Presentation] Thermodynamic Study for Removal of Phosphorus from Molten Silicon (2012)
  • Author(s): Takashi Nagai, Hideaki Sasaki, Masafumi Maeda
  • Organizer: 2012 TMS Annual Meeting & Exhibition
  • Place of Presentation: Orlando, FL, USA.
  • Year and Date: 2012-03-14
• [Presentation] Thermodynamic Study for Removal of Phosphorus from Molten Silicon (2012)
  • Author(s): Takashi Nagai, Hideaki Sasaki, Masafumi Maeda
  • Organizer: 2012 TMS Annual Meeting & Exhibition
  • Place of Presentation: Orlando, FL, USA
• [Presentation] シリコンからの脱 リン のための熱力 学 (2011)
  • Author(s): 永井崇, 前田正史
  • Organizer: 日本金属学会秋季大会
  • Place of Presentation: 沖縄
  • Year and Date: 2011-11-07
• [Presentation] Removal of Phosphorus from Molten Silicon by Electron Beam Melting Technique (2011)
  • Author(s): Takashi Nagai and Masafumi Maeda
  • Organizer: European Metallurgical Conference EMC 2011(6th European Metallurgical Conference)
  • Place of Presentation: Dusseldorf, Germany.
  • Year and Date: 2011-06-28
• [Presentation] Purification of Silicon by Electron Beam Melting Technique (2011)
  • Author(s): T. Kageyama, T. Nagai and M. Maeda
  • Organizer: The 6th Workshop on Reactive Metal Processing
  • Place of Presentation: Pasadena, CA, USA (ポスター発表)
  • Year and Date: 2011-03-17
• [Presentation] Purification of Silicon by Electron Beam Melting Technique (2011)
  • Author(s): T. Nagai, T. Kageyama and M. Maeda
  • Organizer: 2011 TMS Annual Meeting & Exhibition
  • Place of Presentation: San Diego, CA, USA.
  • Year and Date: 2011-03-03
• [Presentation] Purification of Silicon by Electron Beam Melting Technique (2011)
  • Author(s): Takashi Nagai; Tomoki Kageyama; Masafumi Maeda
  • Organizer: TMS 2011 annual meeting
  • Place of Presentation: San Diego, California, USA
  • Year and Date: 2011-03-03
• [Presentation] Purification of Silicon by Electron Beam Melting Technique (2011)
  • Author(s): T.Nagai, T.Kageyama, M.Maeda
  • Organizer: 2011 TMS Annual Meeting & Exhibition
  • Place of Presentation: San Diego, USA
  • Year and Date: 2011-03-03
• [Presentation] Removal of Phosphorus from Molten Silicon by Electron Beam Melting Technique (2011)
  • Author(s): Takashi Nagai and Masafumi Maeda
  • Organizer: European Metallurgical Conference EMC 2011(6th European Metallurgical Conference)
  • Place of Presentation: Dusseldorf, Germany
• [Presentation] シリコンからの脱リンのための熱力学 (2011)
  • Author(s): 永井 崇, 前田正史
  • Organizer: 日本金属学会 秋季大会
  • Place of Presentation: 沖縄
• [Presentation] 電子ビーム溶解法による溶融 Si からの P の 除去 (2010)
  • Author(s): 永井崇,見持貴之,前田正史;
  • Organizer: 日本金属学会
  • Place of Presentation: 札幌.
  • Year and Date: 2010-09-26
• [Presentation] 電子ビーム溶解法による溶融SiからのPの除去 (2010)
  • Author(s): 永井崇、見持貴之、前田正史
  • Organizer: 日本金属学会2010年秋季大会
  • Place of Presentation: 北海道大学
  • Year and Date: 2010-09-26
• [Presentation] 電子ビーム溶解法による溶融SiからのPの除去 (2010)
  • Author(s): 永井崇, 見持貴之, 前田正史
  • Organizer: 日本金属学会
  • Place of Presentation: 北海道大学
  • Year and Date: 2010-09-26
• [Presentation] 溶融シリコンからの不純物除去 (2010)
  • Author(s): 景山友喜, 永井 崇, 木村久雄, 前田正史
  • Organizer: 資源・素材学会関東支部, 第7回「資源・素材・環境」技術と研究の交流会
  • Place of Presentation: 東京 (ポスター)
  • Year and Date: 2010-08-02