We present the experimental results on mapping characterization of the effects of photo-electrochemical (PEC) and inductive coupled plasma (ICP) etchings for both p-type and n-type GaN Schottky contacts by using scanning internal photoemission microscopy to clarify the current transport mechanism. The photoyield (Y) increased in the PEC etched regions by 4%–5% for the n-GaN, by 15% for the p-GaN samples. We proposed a model that the ICP etching induced donor-type damages in the vicinity of the GaN surfaces. In the ICP etched regions, Y increased by 10% for the n-GaN as well, but significantly decreased by 80% for the p-GaN samples. The PEC etching has less effect on the Schottky characteristics than the ICP etching, especially in the p-type sample.

我们通过使用扫描内部光电电子显微镜来阐明电流传输机制，展示了光电化学 (PEC) 和电感耦合等离子体 (ICP) 蚀刻对 p 型和 n 型 GaN 肖特基接触的影响的映射表征的实验结果. 在 PEC 蚀刻区域，n-GaN的光产率 ( Y ) 增加了 4%–5%，p-GaN 样品增加了 15%。我们提出了一个模型，即 ICP 蚀刻在 GaN 表面附近引起施主型损伤。在 ICP 蚀刻区域，n-GaN 的Y 也增加了 10%，但 p-GaN 样品的Y显着降低了 80%。PEC 蚀刻对肖特基特性的影响比 ICP 蚀刻小，尤其是在 p 型样品中。