Residual contrast of threading edge dislocations is observed in synchrotron back‐reflection X‐ray topographs of 4H‐SiC epitaxial wafers recorded using basal plane reflections where both g · b = 0 and g · b × l = 0. The ray‐tracing simulation method based on the orientation contrast formation mechanism is applied to simulate images of such dislocations by applying surface relaxation effects. The simulated contrast features match the observed features on X‐ray topographs, clearly demonstrating that the contrast is dominated by surface relaxation. Depth profiling indicates that the surface relaxation primarily takes place within a depth of 5 µm below the surface.

中文翻译：

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在g·b = 0和g·b×l = 0的条件下，表面弛豫对同步加速器X射线地形图中穿线边缘位错的对比度的影响

在使用基底平面反射记录的4H-SiC外延晶片的同步加速器背向反射X射线形貌图中，观察到螺纹边缘位错的残留对比度，其中g  ·  b = 0和g  ·  b  ×  l =0。射线追踪模拟方法基于取向对比的形成机制被应用于通过施加表面弛豫效应来模拟这种位错的图像。模拟的对比度特征与X射线地形图上观察到的特征相匹配，清楚地表明对比度主要由表面弛豫控制。深度分析表明，表面松弛主要发生在表面以下5 µm的深度内。