Deformation of silicon - Insights from microcompression testing at 25-500°C
Deformation of silicon - Insights from microcompression testing at 25-500°C
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DOI：
10.1016/j.ijplas.2011.05.009
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发表时间：
2011-11-01
影响因子：
9.8
通讯作者：
Clegg, W. J.
中科院分区：
文献类型：
--
作者：
Korte, S.;Barnard, J. S.;Clegg, W. J.
硅和其他脆性材料在室温附近的塑性变形通常在高围压下进行研究，尽管有人认为这可能会改变位错核心结构。在这里，研究了使用微压缩的可能性。使用该方法，在 25 至 500 摄氏度之间测量不同柱直径的硅微柱的屈服应力，直径恒定为 2 μm。没有发现尺寸对屈服应力有明显影响，但从裂纹失效到主要是塑性变形的转变与先前提出的轴向分裂的简单模型一致。通过透射电子显微镜分析变形样本，以阐明操作性脱位机制。这表明，在 500 摄氏度时，变形是通过孪生和部分位错的形成而发生的，而在 100 摄氏度时，变形与微裂纹和仅弱解离位错有关。 (C) 2011 Elsevier Ltd. 保留所有权利。
The plastic deformation of silicon and other brittle materials near room temperature has conventionally been studied under high confining pressures, although it has been suggested that these may modify the dislocation core structure. Here, the possibility of using microcompression has been studied. Using this method the yield stress of silicon micropillars was measured for different pillar diameters and between 25 and 500 degrees C for a constant diameter of 2 mu m. No pronounced effect of size on the yield stress was found, but the transition from failure by cracking to predominately plastic deformation was shown to be consistent with a previously proposed simple model for axial splitting. Deformed specimens were analysed by transmission electron microscopy to elucidate the operative dislocation mechanisms. This showed that at 500 degrees C deformation occurs by twinning and formation of partial dislocations, whereas at 100 degrees C it is associated with micro-cracking and only weakly dissociated dislocations. (C) 2011 Elsevier Ltd. All rights reserved.