Epitaxial abrupt interfaces of multinary compound semiconductors

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K05354
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 30010:Crystal engineering-related
• Research Institution: National Institute of Advanced Industrial Science and Technology
• Principal Investigator: Nishinaga Jiro 国立研究開発法人産業技術総合研究所, エネルギー・環境領域, 主任研究員 (90454058)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: 多元系化合物半導体 / 結晶成長 / 電子デバイス / 光デバイス / 分子線エピタキシー / 太陽電池

Outline of Final Research Achievements

Multinary-compound semiconductors have potentials for many applications, and electronic and optical devices made from multinary compounds expect to achieve high performance, high functionality, and low environmental impact. However, the formation of their heterointerfaces, which are essential for device applications, has been extremely difficult due to thermal diffusion and chemical reactions between the elements. In this research, we succeeded in suppressing segregation and thermal diffusion during deposition by precisely controlling the compound composition, and abrupt heterointerfaces were achieved. High efficiency solar cells were realized using the abrupt heterointerfaces.

Free Research Field

半導体工学

Academic Significance and Societal Importance of the Research Achievements

多元系化合物半導体エピタキシャル成長の研究は、30年以上前に国際的に盛んであったが、ガラス基板上多結晶太陽電池がトレンドとなって以降、研究の進展はまったくない。本研究によって、変換効率10%であった単結晶Cu(In,Ga)Se2太陽電池が、変換効率21.3%に改善された。単結晶化されたCu(In,Ga)Se2は、表面ポテンシャルが均一となり、基礎的物性の評価に最適といえる。本研究は多元系化合物半導体ヘテロ界面の基礎研究であり、今後、急峻なヘテロ界面を利用した量子効果デバイスへの展開が期待される。