Growth of GaAsPN alloys for flexible efficient photovoltaics

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K04488
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 21050:Electric and electronic materials-related
• Research Institution: Toyohashi University of Technology
• Principal Investigator: Yamane Keisuke 豊橋技術科学大学, 工学(系)研究科(研究院), 助教 (80610815)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 太陽電池 / 結晶成長 / 第一原理計算 / 希薄窒化物結晶

Outline of Final Research Achievements

We proposed dilute nitride crystals as a new material that can realize high-efficiency flexible solar cells that can be installed in various locations, and investigated the crystal formation mechanism, device demonstration, and extraction of issues for practical application. As a result, we established growth conditions for GaAsPN alloy crystals with the required absorption energy band (1.7 eV) and fabricated solar cell test devices. In order to overcome the nitrogen-induced point defects that were identified as an issue, we obtained important knowledge on the defect annihilation process from first-principles calculations. We have gotten a patent on the crystal flexibility as an elemental technology, and were able to summarize the obtained results in an academic paper.

Free Research Field

結晶工学

Academic Significance and Societal Importance of the Research Achievements

太陽電池応用に必要とされる吸収エネルギー帯をもつ希薄窒化物結晶の成長条件の確立と併せて、実用化に向けて、フレキシブル化（転写技術）に関する特許を取得できた。また、作製した太陽電池の効率は3%と未だ低いものの、実施例のない新規材料でデバイス動作を確認し、典型値を得たことには大きな意味があると考えられる。今後、転写技術を生かした、既存のフレキシブル太陽電池との組み合わせによる高効率化、格子定数とバンドギャップの自由度を活かした、大面積Si基板を活用できる様々な電子デバイスへの応用も期待される。