Development of crystal growth technology for architecture of microstructures in bulk multicrystals and its application to high-efficiency solar cells

2008 Fiscal Year Final Research Report

• Project/Area Number: 18686001
• Research Category: Grant-in-Aid for Young Scientists (A)
• Allocation Type: Single-year Grants
• Research Field: Applied materials science/Crystal engineering
• Research Institution: Tohoku University
• Principal Investigator: USAMI Noritaka Tohoku University, 金属材料研究所, 准教授 (20262107)
• Project Period (FY): 2006 – 2008
• Keywords: バルク多結晶 / 結晶成長 / 太陽電池

Research Abstract

多結晶の融液成長過程における結晶方位や結晶粒界の形成機構と制御因子を結晶成長学の観点から明確にし、得られた知見に基づき、結晶方位・粒界性格分布を制御したバルク多結晶の成長技術の開発を行った。実際に、結晶欠陥を低減したSiバルク多結晶を実現し、太陽電池の変換効率の向上を示すことで、多結晶組織を制御することがマクロ特性の改善に有用であることを実証した

Research Products

• [Journal Article] Quantitative analysis of sub-grain boundaries in Si multicrystals and their impact on electrical properties and solar cell performance (2009)
  • Author(s): K. Kutsukake, N. Usami, T. Ohtaniuchi, K. Fujiwara, and K. Nakajima
  • Journal Title: J. Appl. Phys 105 Pages: 044909
  • Peer Reviewed
• [Journal Article] Floating cast method to realize high-quality Si bulk multicrystals for solar cells (2009)
  • Author(s): Y. Nose, I. Takahashi, W. Pan, N. Usami, K. Fujiwara, and K. Nakajima
  • Journal Title: J. Cryst. Growth 311 Pages: 228-231
  • Peer Reviewed
• [Journal Article] 太陽電池用高品質シリコンバルク多結晶の製造技術 (2009)
  • Author(s): 宇佐美徳隆, 藤原航三, 沓掛健太朗, 中嶋一雄
  • Journal Title: 電子材料 48 Pages: 10-16
• [Journal Article] Poly-Si film with long carrier lifetime prepared by rapid thermal annealing of Cat-CVD amorphous silicon thin films (2008)
  • Author(s): K. Ohdaira, Y. Abe, M. Fukuda, S. Nishizaki, N. Usami, K. Nakajima, T. Karasawa, T. Torikai, and H. Matsumura
  • Journal Title: Thin Solid Films 516 Pages: 600-603
  • Peer Reviewed
• [Journal Article] Siバルク多結晶の組織制御による太陽電池の高効率化 (2008)
  • Author(s): 宇佐美 徳隆. 藤原航三, 沓掛健太朗, 中嶋一雄
  • Journal Title: 電子情報通信学会技術研究報告 108 Pages: 73-76
• [Journal Article] Impact of defect density in Si bulk multicrystals on gettering effect of impurities (2008)
  • Author(s): I. Takahashi, N. Usami, R. Yokoyama, Y. Nose, K. Kutsukake, K. Fujiwara, and K. Nakajima
  • Journal Title: Jpn. J. Appl. Phys 47 Pages: 8790-8792
  • Peer Reviewed
• [Journal Article] Structural origin of a cluster of bright spots in reverse bias electroluminescence image of solar cells based on Si multicrystals (2008)
  • Author(s): N. Usami, K. Kutsukake, K. Fujiwara, I. Yonenaga, and K. Nakajima
  • Journal Title: Appl. Phys. Express 1 Pages: 075001
  • Peer Reviewed
• [Journal Article] Growth mechanism of Si-faceted dendrites (2008)
  • Author(s): K. Fujiwara, K. Maeda, N. Usami, K. Nakajima
  • Journal Title: Phys. Rev. Lett 101 Pages: 055503
  • Peer Reviewed
• [Journal Article] In situ observation of Si faceted dendrite growth from low-degree-of-undercooling melts (2008)
  • Author(s): K. Fujiwara, K. Maeda, N. Usami, G. Sazaki, Y. Nose, A. Nomura, T. Shishido and K. Nakajima
  • Journal Title: Acta Materialia 56 Pages: 2663-2668
  • Peer Reviewed
• [Journal Article] Modification of local structures in multicrystals revealed by spatially resolved X-ray rocking curve analysis (2007)
  • Author(s): N. Usami, K. Kutsukake, K. Fujiwara, and K. Nakajima
  • Journal Title: J. Appl. Phys 102 Pages: 103504
  • Peer Reviewed
• [Journal Article] Formation mechanism of parallel twins related to Si-facetted dendrite growth (2007)
  • Author(s): K. Fujiwara, K. Maeda, N. Usami, G. Sazaki, Y. Nose and K. Nakajima
  • Journal Title: Scripta Materialia 57 Pages: 81-84
  • Peer Reviewed
• [Journal Article] Structure and its influence on electrical activity of a near {310}Σ5 grain boundary in bulk silicon (2007)
  • Author(s): K. Kutsukake, N. Usami, K. Fujiwara, Y. Nose, and K. Nakajima
  • Journal Title: Materials Transaction 48 Pages: 143-147
  • Peer Reviewed
• [Journal Article] Influence of structural imperfection of Σ5 grain boundaries in bulk multicrystalline Si on their electrical activities (2007)
  • Author(s): K. Kutsukake, N. Usami, K. Fujiwara, Y. Nose, and K. Nakajima
  • Journal Title: J. Appl. Phys 101 Pages: 063509
  • Peer Reviewed
• [Journal Article] Improvement in the conversion efficiency of single-junction SiGe solar cells by intentional introduction of the compositional distribution (2007)
  • Author(s): M. Tayanagi, N. Usami, W. Pan, K. Ohdaira , K. Ujiwara , Y. Nose , and K. Nakajima
  • Journal Title: J. Appl. Phys 101 Pages: 054504
  • Peer Reviewed
• [Journal Article] High-quality poly-crystalline silicon films with minority carrier lifetimes over 5μs formed by flash lamp annealing of precursor amorphous Si films prepared by catalytic chemical vapor deposition (2007)
  • Author(s): K. Ohdaira, S. Nishizaki, Y, Endo, T. Fujiwara, H. matsumura, N. Usami, and K. Nakajima
  • Journal Title: Jpn. J. Appl. Phys 46 Pages: 7198-7203
  • Peer Reviewed
• [Journal Article] シリコンバルク多結晶太陽電池の粒界設計に向けて (2007)
  • Author(s): 沓掛健太朗, 宇佐美徳隆, 藤原航三, 中嶋一雄
  • Journal Title: マテリアルインテグレーション 20 Pages: 31-36
  • Peer Reviewed
• [Journal Article] Effect of the compositional distribution on the photovoltaic power conversion of SiGe solar cells (2007)
  • Author(s): N. Usami, W. Pan, K. Fujiwara, M. Tayanagi, K. Ohdaira, and K. Nakajima
  • Journal Title: Solar Energy Mat. And Solar Cells 91 Pages: 123-128
  • Peer Reviewed
• [Journal Article] 太陽電池用Siバルク多結晶成長技術 (2007)
  • Author(s): 宇佐美徳隆, 藤原航三, 藩伍根, 沓掛健太朗, 野瀬嘉太郎, 中嶋一雄
  • Journal Title: 工業材料 55 Pages: 69-72
• [Journal Article] シリコンバルク多結晶の粒界制御に向けて (2006)
  • Author(s): 宇佐美徳隆, 沓掛健太朗, 藤原航三, 野瀬嘉太郎, 中嶋一雄
  • Journal Title: まてりあ 45 Pages: 720-724
  • Peer Reviewed
• [Journal Article] Microstructures of Si multicrystals and their impact on minority carrier diffusion length
  • Author(s): H.Y. Wang, N. Usami, K. Fujiwara, K. Kutsukake, K. Nakajima
  • Journal Title: Acta Materialia (in press)
  • Peer Reviewed
• [Presentation] 結晶成長過程における多結晶組織形成メカニズムとその制御 (2009)
  • Author(s): 宇佐美徳隆, 沓掛健太朗, 藤原航三, 中嶋一雄
  • Organizer: 第56回応用物理学関係連合講演会
  • Place of Presentation: 茨城県つくば市
  • Year and Date: 2009-03-31
• [Presentation] 結晶シリコン太陽電池の現状と課題:結晶成長技術開発の重要性 (2009)
  • Author(s): 宇佐美徳隆
  • Organizer: 電気学会
  • Place of Presentation: 北海道札幌市
  • Year and Date: 2009-03-19
• [Presentation] Comprehensive study of sub-grain boundaries in Si multicrystals toward defect engineering for high-efficiency solar cell (2008)
  • Author(s): N. Usami, K. Kutsukake, K. Fujiwara, and K. Nakajima
  • Organizer: 5th International Symposium on Advanced Science and Technology of Silicon Materials
  • Place of Presentation: Kona (USA)
  • Year and Date: 2008-11-12
• [Presentation] Toward defect engineering in Si multicrystal for high-efficiency solar cells : Fundamental mechanisms of generation of sub-grain boundaries, spatial distribution, electrical properties, and impact on solar cell performance (2008)
  • Author(s): N. Usami, K. Kutsukake, K. Fujiwara, T. Ohtaniuchi, and K. Nakajima
  • Organizer: 23rd European Photovoltaic Solar Energy Conference and Exhibition
  • Place of Presentation: Velencia(Spain)
  • Year and Date: 2008-09-03
• [Presentation] Reduction of shunt resistance in solar cells based on Si multicrystals by accumulated impurities at subgrain boundaries (2008)
  • Author(s): N. Usami, K.Kutsukake, K. Fujiwara, and K. Nakajima
  • Organizer: The Fourth Asian Conference on Crystal Growth and Crystal Technology (CGCT-4)
  • Place of Presentation: 宮城県仙台市
  • Year and Date: 2008-05-23
• [Presentation] Challenges toward high-efficiency solar cells (2008)
  • Author(s): N. Usami, K. Fujiwara, K. Kutsukake, and K. Nakajima
  • Organizer: Tech Horizon 200
  • Place of Presentation: Riverside (USA)
  • Year and Date: 2008-05-06
• [Presentation] Siバルク多結晶の組織制御による太陽電池の高効率化 (2008)
  • Author(s): 宇佐美徳隆, 藤原航三, 沓掛健太朗, 中嶋一雄
  • Organizer: 電子情報通信学会・シリコン材料・デバイス研究会
  • Place of Presentation: 沖縄県那覇市
  • Year and Date: 2008-04-12
• [Presentation] Fundamental study toward engineering of microstructures in Si multicrystals (2008)
  • Author(s): N. Usami, K. Fujiwara, K. Kutsukake, and K. Nakajima
  • Organizer: 4th Workshop on the Future Directions of Photovoltaics
  • Place of Presentation: Tokyo
  • Year and Date: 2008-03-06
• [Presentation] Fundamental study on Si melt growth toward engineering of microstructures in multicrystalline Si (2008)
  • Author(s): N. Usami, K. Kutsukake, K. Fujiwara, and K. Nakajima
  • Organizer: Mini PV conference
  • Place of Presentation: Trondheim, Norway
  • Year and Date: 2008-01-09
• [Presentation] Si-based crystals for photovoltaic and photonic applications (2007)
  • Author(s): N. Usami
  • Organizer: 日仏ジョイントフォーラム
  • Place of Presentation: Sendai, Japan
  • Year and Date: 2007-12-13
• [Presentation] Spatially resolved X-ray rocking curve analysis as a tool to invesitagte local structures in Si multicrystals (2007)
  • Author(s): N. Usami, K. Kutsukake, K. Fujiwara, and K. Nakajima
  • Organizer: The second international workshop on science and technology of crystalline Si solar cells
  • Place of Presentation: Xiamen, China
  • Year and Date: 2007-12-10
• [Remarks] ホームページ等
  • URL: http://www.xtalphys.imr.tohoku.ac.jp
• [Patent(Industrial Property Rights)] Si結晶インゴットの製造方法 (2007)
  • Inventor(s): 宇佐美徳隆, 中嶋一
  • Industrial Property Rights Holder: 東北大学
  • Industrial Property Number: 特許,特願2007-336605
  • Filing Date: 2007-08-23
• [Patent(Industrial Property Rights)] バルク多結晶材料の製造方法 (2006)
  • Inventor(s): 宇佐美徳隆, 藤原航三, 中嶋一雄
  • Industrial Property Rights Holder: 東北大学
  • Industrial Property Number: 特許,特願2006-227131
  • Filing Date: 2006-08-23