Confocal differential interference contrast microscopy detected dots and line contrasts on the surface of epi-ready (0001) GaN wafers. Large and small dots consisted of pits, ~1.4 μm in width and ~7 nm in depth, and ~0.5 μm in width and ~2.7 nm in depth, respectively; the pits mainly formed on the outcrops of dislocations, with Burgers vectors |b|>c and b=a, respectively, via inadequate chemical mechanical polishing. Lines consisted of scratches induced via polishing. Deep scratches accompanied dense basal plane dislocation loops.

中文翻译：

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通过共焦微分干涉对比显微镜观察到的外延 GaN 晶片表面精细结构的识别

共焦微分干涉对比显微镜检测到外延就绪 (0001) GaN 晶片表面上的点和线对比。大点和小点由凹坑组成，宽约 1.4 微米，深约 7 纳米，宽约 0.5 微米，深约 2.7 纳米；由于化学机械抛光不充分，凹坑主要形成在位错的露头上，Burgers 向量分别 |b|>c 和 b=a。线条由抛光引起的划痕组成。深划痕伴随着密集的基底平面位错环。