【摘要】 采用1000W卤钨灯作为光源,对GaN外延膜在KOH溶液中进行化学腐蚀,以显示晶体位错.采用扫描电子显微镜、原子力显微镜观察位错密度及表面形貌,得到了清晰的腐蚀图形.提出了腐蚀机理,光照激发位错处产生电子空穴对,加速位错处的腐蚀速率.GaN表面出现了大量的六角腐蚀坑(位错露头).优化了KOH溶液的腐蚀条件.更多还原

【Abstract】 A new method for the light-assisted wet etching of GaN is demonstrated,the light source for which is a tungsten halide lamp.The dislocation density and surface morphology are investigated by scanning electron microscopy and atomic force microscopy,and an optimal etching morphology is obtained.It is also demonstrated that the light source induces electron-hole pairs and enhances the etching rate at the dislocation sites.Many hexagonal etching pits,which emergence at the dislocations,are observed.The etching mechanism is discussed,and an optimal etching condition is proposed.更多还原