Novel broadband mid-infrared emitting quantum structures fabricated by metal organic vapor phase epitaxy

2024 Fiscal Year Final Research Report

• Project/Area Number: 22K04245
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 21060:Electron device and electronic equipment-related
• Research Institution: University of Miyazaki
• Principal Investigator: Maeda Koji 宮崎大学, 工学部, 教授 (50219268)
• Co-Investigator(Kenkyū-buntansha): 藤澤 剛 法政大学, 理工学部, 教授 (70557660) ; 荒井 昌和 宮崎大学, 工学部, 准教授 (90522003)
• Project Period (FY): 2022-04-01 – 2025-03-31
• Keywords: 超格子 / 中赤外発光 / フォトルミネッセンス / バンド構造計算 / MOCVD / 発光遷移 / 温度依存性 / 励起強度依存性

Outline of Final Research Achievements

The goal of this research is to create a device capable of emitting infrared light over a wide range of wavelengths. First, band structure calculations revealed that a design between higher energy levels was more important than between the lowest levels for strong light emission at room temperature. Next, materials were fabricated based on that design, but the luminescence was weaker than expected. Therefore, we improved the intensity by devising protective and buffer layers, which were not taken into account in the calculations. From the luminescence details, it was found that the emission tended to match the predicted spectral shape at low temperatures and in weak light, but that there were wavelength differences and a decrease in intensity in strong light. Although luminescence over a wide wavelength range was achieved at room temperature, due to the decrease in luminescence intensity with increasing temperature, we will aim to reduce defects in the future.

Free Research Field

半導体物性

Academic Significance and Societal Importance of the Research Achievements

室温で励起強度を変化させて発光強度やスペクトル形状まで計算し、その構造を実際に作製し計算と実験のスペクトルを比較したことは、学術的に意義がある。まだ、発光強度は強くないが計算上中赤外領域で広い発光波長範囲をもつtype II超格子が実現できる可能性を示せたことは、実現する上で意義がある結果となった。