Improvement of quality in nitrides semiconductor slab-type photonic crystals and their application to photonic integrated circuits

2023 Fiscal Year Final Research Report

• Project/Area Number: 20K14788
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 21060:Electron device and electronic equipment-related
• Research Institution: The University of Electro-Communications
• Principal Investigator: Tajiri Takeyoshi 電気通信大学, 大学院情報理工学研究科, 准教授 (00842949)
• Project Period (FY): 2020-04-01 – 2024-03-31
• Keywords: III族窒化物半導体 / フォトニック結晶

Outline of Final Research Achievements

Air-suspended gallium nitride thin films with periodic refractive indices in plane (GaN slab-type photonic crystals) are expected for photonic circuit applications in visible wavelengths. This study addressed the improvement of their fabrication by employing a novel chemical etching technique where chemical reactions are induced by laser light. Using this method, we selectively removed the indium gallium nitride underneath the GaN slab-type photonic crystal. This led to GaN photonic crystal cavities with higher confinement strength for visible light, compared to conventional methods. This work would pave the way towards high-quality fabrication of optical circuit elements based on GaN slab-type photonic crystals for visible light control.

Free Research Field

ナノフォトニクス

Academic Significance and Societal Importance of the Research Achievements

本成果は、GaNスラブ型フォトニック結晶をこれまでより高品質に作製するための新たな加工技術を明らかにしたものである。GaNスラブ型フォトニック結晶を基盤とする微細な可視光制御素子の高品質化が進展することで、可視光帯で動作する微細な素子を集積した光回路技術への応用展開が期待される。また、GaN系半導体のデバイス加工技術として従来から用いられる光電気化学エッチング法の高度化は、光デバイスの枠組みを超えた広範なデバイスの作製技術としても、今後その貢献が期待される。