Structural elements on reconstructed Si and Ge(110) surfaces -: art. no. 045305
Structural elements on reconstructed Si and Ge(110) surfaces -: art. no. 045305
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DOI：
10.1103/physrevb.70.045305
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发表时间：
2004-07-01
影响因子：
3.7
通讯作者：
Bechstedt, F
中科院分区：
文献类型：
--
作者：
Stekolnikov, AA;Furthmüller, J;Bechstedt, F
我们对Si和Ge(110)表面可能的重构元素进行了从头算研究。利用2x2、3x2和6x2晶胞，我们优化了在较大的Si(110)16x2或Ge(110)16x2/c(8x10)表面重构上可能存在的弯曲原子链、二聚体、不同的吸附原子分布和间隙原子的模型。我们证明了吸附原子重构获得了能量。只有表面上没有悬垂键的吸附原子模型才不可能出现在Si和Ge(110)表面上。吸附原子-静止原子的电子转移机制更为有利。吸附原子-四聚体-间隙3x2模型也稳定了Si和Ge表面，并导致了半导体行为(至少对Si是这样)。这种重建的空态的模拟扫描隧道显微镜(STM)图像看起来像在Si(110)16x2上观察到的五边形结构。一个6x2的五元团簇重建在能量上是完全不利的，尽管它也再现了空态的五角形STM图像。
We present ab initio studies of possible reconstruction elements on Si and Ge(110) surfaces. Using 2x2, 3x2, and 6x2 unit cells we optimize models with buckled atomic chains, dimers, different adatom distributions, and interstitial atoms which may exist on the larger Si(110)16x2 or Ge(110)16x2/c(8x10) surface reconstructions. We show that adatom reconstructions gain energy. Only the adatom model which seemingly leaves no dangling bonds cannot occur on Si and Ge(110) surfaces. An adatom-rest atom electron transfer mechanism is more favorable. An adatom-tetramer-interstitial 3x2 model also stabilizes the Si and Ge surfaces and leads to a semiconducting behavior (at least for Si). Simulated scanning tunneling microscopy (STM) images of empty states of this reconstruction look like the pentagon structures observed on Si(110)16x2. A 6x2 reconstruction with five-membered adclusters is energetically completely unfavorable, though it also reproduces the empty-state pentagonlike STM images.