当前位置: X-MOL 学术Comp. Mater. Sci. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Intersections of two stacking faults in zincblende GaN
Computational Materials Science ( IF 3.1 ) Pub Date : 2020-07-01 , DOI: 10.1016/j.commatsci.2020.109620
Zdeněk Antoš , Petr Vacek , Roman Gröger

Abstract The structure and energetics of an isolated { 1 1 1 } stacking fault and the interactions of two non-coplanar { 1 1 1 } stacking faults in zincblende GaN are investigated using an empirical potential of the Tersoff-Brenner type. For a single stacking fault, a metastable configuration is found only when the fault is created on the { 1 1 1 } plane in the glide set, which results in local transformation into a more stable wurtzite structure. This energetically favorable configuration is separated from the unfaulted crystal by a large energy barrier. Interactions between two stacking faults on non-coplanar { 1 1 1 } planes, where one fault corresponds to the metastable configuration created in the glide set and the second fault is created on a different { 1 1 1 } plane, lead to a reduction of the aforementioned energy barrier and an increase of the energy of the second metastable fault. The intersection of the two faults results in a significant reconstruction of atomic positions around the line common to both faults. Apart from the wurtzite stacking, the structure of this intersection shows a partial transformation into the rocksalt structure that is normally stable only at high pressures. The presence of this high-energy rocksalt structure is avoided if the second fault is non-planar. In this case, four different structures of the intersection exist. We demonstrate that one of these structures agrees well with TEM observations.

中文翻译:

闪锌矿 GaN 中两个堆垛层错的交点

摘要 利用 Tersoff-Brenner 型经验势研究了闪锌矿 GaN 中孤立的 { 1 1 1 } 堆垛层错的结构和能量学以及两个非共面 { 1 1 1 } 堆垛层错的相互作用。对于单个堆垛层错,只有在滑移组的 { 1 1 1 } 平面上产生断层时才会发现亚稳态配置,这导致局部转变为更稳定的纤锌矿结构。这种能量上有利的配置通过一个大的能量势垒与无缺陷的晶体分开。非共面 { 1 1 1 } 平面上的两个堆垛层错之间的相互作用,其中一个断层对应于滑移组中创建的亚稳态配置,第二个断层在不同的 { 1 1 1 } 平面上创建,导致上述能垒的降低和第二亚稳断层能量的增加。两个断层的交叉导致两个断层共有的线周围的原子位置的显着重建。除了纤锌矿堆积之外,该交叉点的结构显示出部分转变为通常仅在高压下稳定的岩盐结构。如果第二个断层是非平面的,就可以避免这种高能岩盐结构的存在。在这种情况下,存在四种不同的交叉结构。我们证明这些结构之一与 TEM 观察结果非常吻合。除了纤锌矿堆积之外,该交叉点的结构显示出部分转变为通常仅在高压下稳定的岩盐结构。如果第二个断层是非平面的,就可以避免这种高能岩盐结构的存在。在这种情况下,存在四种不同的交叉结构。我们证明这些结构之一与 TEM 观察结果非常吻合。除了纤锌矿堆积之外,该交叉点的结构显示出部分转变为通常仅在高压下稳定的岩盐结构。如果第二个断层是非平面的,就可以避免这种高能岩盐结构的存在。在这种情况下,存在四种不同的交叉结构。我们证明这些结构之一与 TEM 观察结果非常吻合。
更新日期:2020-07-01
down
wechat
bug