Proposal of improving energy conversion efficiency of solar cell by phonon confinement

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K17511
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Crystal engineering
• Research Institution: Chiba University
• Principal Investigator: MA BEI 千葉大学, 大学院工学研究院, 助教 (90718420)
• Research Collaborator: Ishitani Yoshihiro ; Miyake Hideto
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: フォノン

Outline of Final Research Achievements

(1) Assuming an AlGaN-based quantum well structure and phonon localization as a parameter and comparing optical phonons with acoustic phonons, it has been found that the optical phonon has the most influence on the carrier extraction rate.
(2) electron concentration distribution in high density Si-doped GaN films
As a result of fitting analysis based on the infrared reflection spectrum, a changing in the electron concentration distribution in the depth direction was obtained for the sample with an electron concentration of 3E20 cm-3 estimated by Hall measurement. From the spectrum of Raman spectroscopy, it is considered that in the high electron concentration sample, the crystallinity deterioration due to doping, the formation of the acceptor level due to the occupation of the N position of Si, and the electron concentration reduction towards the surface due to the doping to the interstitial site.

Free Research Field

半導体

Academic Significance and Societal Importance of the Research Achievements

量子井戸構造のフォノン・キャリア動的過程計算では、光学フォノンを制御することで、励起子発光の効率改善を示した。薄膜の測定結果では、電子濃度の空間的解析を行った。材料中の転位や不純物の空間濃度解析はそれらの制御、フォノンバンド構造制御等による空間的フォノン輸送制御に役に立つ。