由有機金屬化學氣相沈積成長不同中斷時間對生成氮化銦奈米粒的影響研究

Abstract

我們利用重複次數的「成長中斷模式」（growth interruptions）在700oC成功成長出無金屬銦顆粒（In droplet）的氮化銦微結構。可以解決氮化銦難以在高溫成長的問題。實驗結果顯示當每次截斷TMIn供應而保持NH3通入的時間超過15秒，重複45次之後表面不但沒有金屬銦顆粒存在，PL發光譜峰也由0.75eV降低至0.7eV。這個結果，據我們所知已不遜於世界級的水準。利用時間解析光譜量測所顯示低溫載子侷限能量大約20 meV，超過一般量測約5至10 meV的結果，我們判斷0.7eV的發光是經由靠近價帶的深層能階所主導。

We introduced repetitive growth interruptions for successfully growth of InN dots without In droplets at 700 oC once interruption time at each cycle exceeds 15 seconds. Total amount of indium atoms at droplet-existing and droplet-free regime are valued at 3.96±0.38 and 4.38±0.69 mol/cm2.Although a~20% of volume of the hollow dots might be overestimating at droplet-free regime, it is probably suggested In convert to InN rather than evaporation. We observed not only the conversion process, long enough interruption times results in a PL peak energy at 0.7eV rather than 0.75eV. Temperature-dependent PL measurement showed the S-shaped behavior below 220K that indicates a strong localization effect. Results of time-resolved photoluminescence reveals the localization energy about 20meV, and we probably believed the 0.7eV emission involves a deep level.