Atomistic simulation of structural phase transformations in monocrystalline silicon induced by nanoindentation
Atomistic simulation of structural phase transformations in monocrystalline silicon induced by nanoindentation
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纳米压痕诱导单晶硅结构相变的原子模拟
DOI：
10.1088/0957-4484/17/9/031
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发表时间：
2006-05-14
期刊：
影响因子：
3.5
通讯作者：
Oh, S. I.
中科院分区：
文献类型：
--
作者：
Kim, D. E.;Oh, S. I.
在原子层面详细研究了纳米压痕过程中硅的结构相变。对单晶硅（100）和（111）表面的纳米压痕进行了分子动力学模拟，这支持了结构相变各向异性行为的理论预测。模拟表明，相变的微观方面根据接触面的晶体取向而变化，并与硅的滑移系直接相关。在沿中心线的转变区域中，当硅分别在[100]和[111]方向加载时，观察到了Si - II的晶体结构和非晶结构。同时，具有四重配位的亚稳相，如Si - III和Si - XII，是由硅滑移方向的不均匀畸变形成的，并沿<110>方向被观察到。此外，我们的结果表明，在（100）表面纳米压痕过程中，加载引起的偏应力加上静水压力是结构相变为Si - II的一个不可或缺的因素。
Structural phase transformations of silicon during nanoindentation were investigated in detail at the atomic level. The molecular dynamics simulations of nanoindentation on the (100) and (111) surface of single crystalline silicon were simulated, and this supported the theoretical prediction of the anisotropic behaviour of structural phase transformations. Simulations showed that microscopic aspects of phase transformation varied according to the crystallographic orientation of the contact surface and were directly linked to the slip system of silicon. In the transformed region along the centreline, the crystalline structure of Si-II and the amorphous structure were observed when silicon was loaded in the [100] and [111] directions, respectively. Simultaneously, metastable phases with fourfold coordination, such as Si-III and Si-XII, were formed by the inhomogeneous distortion in the slip direction of silicon and observed along the < 110 > direction. Additionally, our results indicated that the deviatoric stress added to the hydrostatic pressure induced by loading was an indispensable factor for the structural phase transformation to Si-II during nanoindentation on the (100) surface.