Atomistic structure of amorphous silicon nitride from classical molecular dynamics simulations
Atomistic structure of amorphous silicon nitride from classical molecular dynamics simulations
复制标题
经典分子动力学模拟中非晶氮化硅的原子结构
DOI：
10.1103/physrevb.83.165209
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发表时间：
2011
影响因子：
3.7
通讯作者：
S. Meloni
中科院分区：
文献类型：
--
作者：
M. Ippolito;S. Meloni
利用基于Billeter等人[S. R. Billeter，A. Curioni，D. Fischer和W. Andreoni，Phys. Rev. B 73，155329（2006）]环境依赖的经典力场我们研究了不同化学计量的SiN${}_{x}$样品的结构特征。我们的结果是在良好的协议与实验数据，并能够重现一些功能，到目前为止没有再现模拟。特别是，我们确定了含有N\char21{}N键的单元，这些单元被认为是负责从中子衍射数据和电子自旋共振，X射线光电子能谱，电子能量损失谱和光吸收实验中观察到的信号获得的径向分布函数中的未分配峰。我们已经确定了缺陷，这被认为是负责高浓度的电荷陷阱，使这种材料适用于建立非易失性存储器设备。我们分析了这些缺陷的浓度与样品的化学计量的依赖性。
By means of molecular dynamics simulations based on the Billeter et al. [S. R. Billeter, A. Curioni, D. Fischer, and W. Andreoni, Phys. Rev. B 73, 155329 (2006)] environment-dependent classical force field we studied the structural features of SiN${}_{x}$ samples at various stoichiometries. Our results are in good agreement with experimental data and are able to reproduce some features which so far were not reproduced by simulations. In particular, we identified units containing N\char21{}N bonds, which are thought to be responsible for an unassigned peak in the radial distribution function obtained from neutron diffraction data and signals observed in electron spin resonance, x-ray photoemission spectroscopy, electron-energy-loss spectroscopy, and optical absorption experiments. We have identified defects which are thought to be responsible for the high concentration of charge traps that makes this material suitable for building nonvolatile memory devices. We analyzed the dependency of the concentration of these defects with the stoichiometry of the sample.