Onset of plasticity in InxGa1-xAs multilayers
Onset of plasticity in InxGa1-xAs multilayers
复制标题
InxGa1-xAs 多层膜开始出现塑性
DOI：
10.1016/j.actamat.2009.08.056
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发表时间：
2010
期刊：
影响因子：
9.4
通讯作者：
Korte S
中科院分区：
文献类型：
--
作者：
Korte S
为了确定相干应变对屈服应力的影响，研究了零净应变的相干应变InxGa1-−-xAs多层膜。用纳米压痕和透射电子显微镜研究了变形行为。纳米压痕显示，屈服开始所需的压力随着共聚应变的增加而降低，这与以前的工作一致，而硬度保持不变。透射电子显微镜显示，变形在某一层中更为普遍。利用这些观测结果，发展了一个直接的分析，即多层的屈服压力与由其固有屈服压力和共格应变共同决定的较弱层中的流动开始有关。这与实验观测结果吻合较好，也与文献中关于薄膜内应力效应的观测结果一致。
Coherently strained InxGa1−xAs multilayers with zero net strain have been investigated in order to determine the influence of coherency strains on the yield stress. The deformation behaviour has been studied using both ex- and in situ nanoindentation and transmission electron microscopy. Nanoindentation showed that the pressure required for the onset of yield decreased with increasing coherency strain, consistent with previous work, while the hardness remained constant. Transmission electron microscopy revealed that deformation was more prevalent in one layer. Using these observations, a straightforward analysis has been developed in which the yield pressure of the multilayer is related to the onset of flow in the weaker layer determined by both its intrinsic yield pressure and coherency strains. This gives good agreement with the experimental observations and is consistent with the observations of the effects of internal stresses in films elsewhere in the literature.