【摘要】 采用高分辨X射线衍射对在蓝宝石(0001)面生长的GaN外延膜的漫散射进行了研究.结果表明,GaN薄膜中存在缺陷团,其浓度随着穿透位错密度的增加而增加,其平均半径呈相反趋势.基于位错是点缺陷的聚集区,缺陷团优先在位错附近形成的效应对结果进行了解释.同时发现电子迁移率随缺陷团浓度的增加而减少.更多还原

【Abstract】 High-resolution X-ray diffraction has been employed to investigate the diffuse scattering in a (0001) oriented GaN epitaxial film grown on sapphire substrate.The analysis reveals that defect clusters are present in GaN films and their concentration increases as the density of threading dislocations increases.Meanwhile,the mean radius of these defect clusters shows a reverse tendency.This result is explained by the effect of clusters preferentially forming around dislocations,which act as effective sinks for the segregation of point defects.The electric mobility is found to decrease as the cluster concentration increases.更多还原