高能 238 U离子辐照AlN 晶体薄膜的光学特性研究

通过傅里叶变换红外光谱、拉曼光谱和光致发光谱测试手段分析了由HIRFL 提供的高能238U离 子辐照AlN 晶体薄膜的光学特性变化。辐照后出现了A1(To)，A1(Lo)，E1(To) 和E2 等声子振动吸收模式，并且辐照使其在样品近表面Al—N 等振动模式遭到破坏后悬空的Al— 键很快与空气中的O离子发生结合，形成了Al—O 键。综合分析得出了蓝光发射带是与O 离子相关的VAl-ON-3N 和VAl-2ON-2N两种类型缺陷以及F-型缺陷聚合所致；绿光发射带是由基底中Al 原子产生的价带之间的跃迁所致。 AlN thin film irradiated with 100 MeV 238U ions delivered from HIRFL (Heavy Ion Research Facility in Lanzhou) were investigated by Fourier Transform Infrared spectra, Raman spectra and Photoluminescence spectra. Phonon vibration absorption modes including A1(To), A1(Lo), E1(To) and E2 appeared in the irradiated samples. The irradiation made the Al—N bonds broken and the formation of Al—dangling bonds, which combined soon with oxygen atoms existing in air to form Al—O bonds. Blue light emission band are related to the two types of defects of VAl-ON-3N and VAl-2ON-2N and F-type defects aggregation. Green light emission band is due to energy transition among valence band of Al atoms in sapphire substrate.