Advanced research on semiconductor optical device materials by controlling phonon transport under non-thermal equilibrium state

2016 Fiscal Year Final Research Report

• Project/Area Number: 25286048
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Crystal engineering
• Research Institution: Chiba University
• Principal Investigator: Ishitani Yoshihiro 千葉大学, 工学(系)研究科(研究院), 教授 (60291481)
• Co-Investigator(Kenkyū-buntansha): 篠塚 雄三 和歌山大学, システム工学部, 教授 (30144918) ; 矢口 裕之 埼玉大学, 理工学研究科, 教授 (50239737)
• Co-Investigator(Renkei-kenkyūsha): Ken Morita 千葉大学, 大学院工学研究科, 准教授 (30448344) ; Bei Ma 千葉大学, 大学院工学研究科, 助教 (90718420)
• Research Collaborator: Kensuke Oki 千葉大学, 工学部, 技術補佐員
• Project Period (FY): 2013-04-01 – 2017-03-31
• Keywords: フォノンエンジニアリング / 励起子 / 結晶欠陥 / 窒化物半導体 / 光物性

Outline of Final Research Achievements

Phonon processes affect various carrier dynamics dominating the device properties of semiconductors: energy conversion efficiency of solar cells, association and dissociation of excitons, nonradiative carrier recombination, and so forth are the examples. Many reports discuss the detail dynamics of electron-hole-exciton system, whereas the analysis including all of phonon, electron, and radiation is still at primitive stage. In this research we have characterized the flow of excitation and deexcitation of electron-hole-exciton system by integrating various elementary processes including phononic one and various parameters of electron density and several temperatures reflecting kinetic energies depending on physical material properties, excitation condition, and device structures. Further, we have obtained some results on the effects of phonon localization on the exciton stability and transition rate related to deep levels in GaN.

Free Research Field

半導体工学