Abstract

As a result of in situ irradiation in a high-resolution electron microscope, structure modelling, and calculation of images, it is shown that the incorporation of self-interstitial atoms into the extension region of the core of any dislocation is accompanied by their ordering in the form of cluster-like {111}, {001}, and {113} defects, which provide core relaxation. This fact made it possible to visualize for the first time the core structure of undissociated 60° dislocations of two types, glide (\(60_{{{\text{sh}}}}^{^\circ }\)) and sessile (\(60_{{{\text{gl}}}}^{^\circ }\)), which coexist at plastic deformation of Si. It is shown that incorporation of self-interstitial atoms into the dislocation core correlates with an increase of only the D2 line in the photoluminescence spectrum, while perfect sessile a/2〈110〉 dislocations with a core, consisting of paired 5/7-link atomic rings without dangling bonds, are responsible for the rise of the D1 line. This universal core occurs at coalescence of two \(60_{{{\text{sh}}}}^{^\circ }\) dislocations during their slip in intersecting planes {111}, \(60_{{{\text{sh}}}}^{^\circ }\) → \(60_{{{\text{gl}}}}^{^\circ }\) transition, and transformation of a Frank dislocation into a perfect one.

中文翻译：

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硅中位错核的结构转变及其与光致发光的关系

摘要

高分辨率电子显微镜中原位照射、结构建模和图像计算的结果表明，自填隙原子并入任何位错核心的扩展区域都伴随着它们在簇状 {111}、{001} 和 {113} 缺陷的形式，提供核心松弛。这一事实使得首次可视化两种类型的未解离 60°位错的核心结构成为可能，滑行（\(60_{{{\text{sh}}}}^{^\circ }\)）和固着( \(60_{{{\text{gl}}}}^{^\circ }\) )，它们共存于 Si 的塑性变形中。结果表明，自填隙原子掺入位错核仅与D的增加相关光致发光光谱中的 2 线，而具有核心的完美固着a /2〈110> 位错，由成对的 5/7 连接原子环组成，没有悬空键，是造成D 1 线上升的原因。这个通用核心发生在两个\(60_{{{\text{sh}}}}^{^\circ }\)位错在相交平面 {111} 中滑动期间的合并，\(60_{{{\text{ sh}}}}^{^\circ }\) → \(60_{{{\text{gl}}}}^{^\circ }\)过渡，并将弗兰克位错转化为完美位错。