Nondestructive measurement of crystal defects using multiphoton excitation photoluminescence

2022 Fiscal Year Final Research Report

• Project/Area Number: 20H02640
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 30010:Crystal engineering-related
• Research Institution: Osaka University
• Principal Investigator: Tomoyuki Tanikawa 大阪大学, 大学院工学研究科, 准教授 (90633537)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: ワイドギャップ半導体 / 結晶欠陥 / 多光子励起フォトルミネッセンス / 窒化ガリウム / 酸化ガリウム / ダイヤモンド / シリコンカーバイド

Outline of Final Research Achievements

Observation, classification, and identifiation of crystal defects in widegap semiconductors were demonstrated using multiphoton excitation photoluminescence, and three-dimensional distribution of crystal defects was visualized. In GaN and SiC, dislocations can be visualized as dark lines due to the non-radiative recombination center nature of dislocations, and dislocation species can be identified and classified from shading and three-dimensional images. Furthermore, it was found that in SiC, through-plane dislocations and basal plane dislocations are observed as emission surfaces at wavelengths of around 400-500 nm for stacking faults. In Ga2O3, nanopipes can be visualized and correlated with surface hillock growth. In diamond, dislocations were observed as emission lines, revealing complex bending and propagation behavior during heteroepitaxial growth.

Free Research Field

結晶工学

Academic Significance and Societal Importance of the Research Achievements

多光子励起フォトルミネッセンス法による結晶欠陥評価技術は、次世代半導体に複雑に分布する結晶欠陥の三次元分布を非破壊で可視化できる強力なツールとして、GaN、SiC、Ga2O3、ダイヤモンドと４種類の材料について適用できることを本研究課題を通じて示すことができた。これらの成果を基に結晶工学の発展と、次世代半導体を用いた光デバイスや電子デバイスの性能向上や信頼性向上に貢献しうるものと期待している。