High growth-rate hydride-vapor-phase of aluminum nitride

氮化铝是一种有吸引力的短波长光电子器件的AlGaN基片。对于AlN和AlGaN的生长，使用图案化衬底的横向过生长对于控制位错渗透是有用的，因为不能应用利用掩模（例如SiO2）的选择性区域生长。在本研究中，通过HVPE生长厚AlN薄膜上的AlN/蓝宝石条纹图案化的种子具有三角形的横截面，和HVPE生长的薄膜的表面上的TDs的密度降低了一个数量级的AlN薄膜没有图案的种子。我们还用腐蚀坑法研究了外延AlN薄膜中的穿透位错。采用混合酸溶液（KOH+ NaOH）腐蚀AlN外延膜。根据这些尺寸将蚀刻坑分为TD组。

AlN is an attractive substrate for short-wavelength optoelectronics devices based on AlGaN. For growth of AlN and AlGaN, lateral overgrowth using a patterned substrate is useful for control of dislocation penetration, because selective-area growth with masks, such as SiO2, cannot be applied. In this study, thick AlN films were grown by HVPE on AlN/sapphire stripe patterned seeds with triangular shape in cross section, and the TDs density on the surface of HVPE-grown films was reduced one order of magnitude from a AlN film without pattern seeds. We also have investigated threading dislocations(TDs) in epitaxial AlN films by etch-pit method. Epitaxial AlN films were etched by mixed acid solution(KOH+ NaOH). The etch-pits were classified into TD groups by those sizes.