中文摘要：

An Al0.2Ga0.8N/AlN/Al0.2Ga0.8N heterostructure was grown by metalorganic chemical vapor deposition on a sapphire(0001) substrate with a thick(> 1 μm) GaN intermediate layer. The Al composition was determined by Rutherford backscattering(RBS). Using the channeling scan around an off-normal [1213] axis in the(1010) plane of the Al0.2Ga0.8N layer, the tetragonal distortion eT, which is caused by the elastic strain in the epilayer, is investigated. The results show that eTin the high-quality Al0.2Ga0.8N layer is dramatically released by the AlN interlayer from 0.66% to 0.27%.

英文摘要：

An Al0.2Ga0.8N/AlN/Al0.2Ga0.8N heterostructure was grown by metalorganic chemical vapor deposition on a sapphire （0001） substrate with a thick （〉 1 μm） GaN intermediate layer. The Al composition was determined by Rutherford backscattering （RBS）. Using the channeling scan around an off-normal [1213] axis in the （1010） plane of the Al0.2Ga0.8N layer, the tetragonal distortion eT, which is caused by the elastic strain in the epilayer, is investigated. The results show that eT in the high-quality Al0.2Ga0.8N layer is dramatically released by the AIN interlayer from 0.66% to 0.27%.