AlN／蓝宝石模板上生长的 Al 0．6Ga0．4N薄膜结构与光学性能研究

摘要

In this work ,Al0.6Ga0.4N films grown on AlN/sapphire templates by metalorganic chemical va-por deposition (MOCVD) system were characterized by high resolution XRD and low temperature cath-odoluminescence (CL ) methods .It’s found that there exists phase separation phenomenon in the films by XRD measurements .The optical properties obtained from CL spectra confirmed this phenomenon further . The generation of phase separation is attributed to stress relaxation in thick films and the low surface mob-ility of Al atoms .%采用MOCVD方法在 AlN/蓝宝石模板上生长高铝组分 Al0．6 Ga0．4 N 薄膜，并采用高分辨率XRD（HRXRD）及阴极荧光（CL）方法对其进行了表征．结果表明，AlGaN薄膜产生了相分离，其原因为厚膜中的应力弛豫及Al原子低的表面迁移率．