Hollow-core screw dislocations along [0001] in hexagonal silicon carbide single crystals, i.e. micropipes, are known to heal or close during annealing or epitaxial growth procedures. Although the healing and closing are understood to be caused by the dissociation of hollow-core superscrew dislocations into multiple closed-core elementary screw dislocations with Burgers vector of 1 c , the transformation mechanism, especially in terms of elastic energy, is unclear. Here, we propose a unique transitional configuration of the super-screw dislocations based on theoretical considerations to well explain the transformation mechanism, which consists of a 1 c -screw-dislocation cluster and dense basal-plane partial dislocation loops. An elastic energy calculation revealed that the activation energy for the loop creation based on the proposed model well explains experimentally derived tendencies of the healing process. Furthermore, we confirmed that the total elastic energy of ...

中文翻译：

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中空螺钉位错的转变：超螺钉位错的过渡构型

在退火或外延生长过程中，六角形碳化硅单晶即微管中沿着[0001]的中空螺杆位错已知会愈合或闭合。尽管愈合和闭合被理解为是由空心超螺旋位错解离为具有1c Burgers向量的多个闭合芯基本螺钉位错，但其转变机理，尤其是在弹性能方面尚不清楚。在这里，我们基于理论上的考虑，提出了一种超螺旋位错的独特过渡构型，以很好地解释由1 c螺旋位错簇和密集的基面部分位错环组成的转变机理。弹性能量计算表明，基于所提出模型的回路创建所需的活化能很好地说明了实验得出的愈合过程趋势。此外，我们证实了...的总弹性能