V‐pit defects in InGaN/GaN were studied by numerical simulations of the strain field and X‐ray diffraction (XRD) reciprocal space maps. The results were compared with XRD and scanning electron microscopy (SEM) experimental data collected from a series of samples grown by metal–organic vapor phase epitaxy. Analysis of the principal strains and their directions in the vicinity of V‐pits explains the pseudomorphic position of the InGaN epilayer peak observed by X‐ray diffraction reciprocal space mapping. The top part of the InGaN layer involving V‐pits relieves the strain by elastic relaxation. Plastic relaxation by misfit dislocations is not observed. The creation of the V‐pits appears to be a sufficient mechanism for strain relaxation in InGaN/GaN epilayers.

中文翻译：

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通过SEM，XRD和数值模拟研究的V形坑缺陷形成导致InGaN / GaN外延层中的应变松弛

通过应变场的数值模拟和X射线衍射（XRD）倒数空间图研究了InGaN / GaN中的V坑缺陷。将结果与XRD和扫描电子显微镜（SEM）实验数据进行了比较，该数据是通过一系列金属有机气相外延生长的样品收集的。对V形凹坑附近的主要应变及其方向的分析解释了通过X射线衍射互易空间映射观察到的InGaN外延层峰的假晶位置。InGaN层的顶部具有V型坑，可通过弹性松弛来缓解应变。没有观察到因错位错位引起的塑性松弛。V坑的产生似乎是InGaN / GaN外延层中应变松弛的充分机制。