Ab initio -based approach to initial growth processes on GaAs ( 111 ) B − ( 2 × 2 ) surfaces: Self-surfactant effect of Ga adatoms revisited
Ab initio -based approach to initial growth processes on GaAs ( 111 ) B − ( 2 × 2 ) surfaces: Self-surfactant effect of Ga adatoms revisited
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DOI：
10.1103/physrevb.77.233306
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发表时间：
2008-06
影响因子：
3.7
通讯作者：
H. Tatematsu;K. Sano;T. Akiyama;K. Nakamura;T. Ito
中科院分区：
文献类型：
--
作者：
H. Tatematsu;K. Sano;T. Akiyama;K. Nakamura;T. Ito
用我们的从头算方法研究了$\text{GaAs}(111)B\text{\ensuremath{-}}(2\ifmmode\times\else\texttimes\fi{}2)$表面的初始生长过程，其中As原子的脱附行为是通过比较总能电子结构计算得到的脱附能和量子统计力学估计的化学势来描述的。我们发现，在有Ga吸附原子的表面上，As-三聚体的脱附发生在40021700K以上，而在无Ga吸附原子的表面上，As-三聚体脱附发生在80021000K以上。由Ga吸附原子引发的As-三聚体脱附的促进作用也可以从能带稳定性的角度来解释。
The initial growth processes on $\text{GaAs}(111)B\text{\ensuremath{-}}(2\ifmmode\times\else\texttimes\fi{}2)$ surfaces are investigated using our ab initio-based approach, in which desorption behavior of As atoms is described by comparing the calculated desorption energy obtained by total-energy electronic-structure calculations with the chemical potential estimated by quantum statistical mechanics. We find that the As-trimer desorption on the $(2\ifmmode\times\else\texttimes\fi{}2)$ surfaces with Ga adatoms occurs beyond 400\char21{}700 K while the desorption without Ga adatom does beyond 800\char21{}1000 K. The promotion of the As-trimer desorption triggered by Ga adatoms called ``self-surfactant effect'' is also found to be interpreted in terms of the band-energy stabilization.