Lattice site locations of excess arsenic atoms in gallium arsenide grown by low‐temperature molecular beam epitaxy
Lattice site locations of excess arsenic atoms in gallium arsenide grown by low‐temperature molecular beam epitaxy
复制标题
低温分子束外延生长砷化镓中过量砷原子的晶格位置
DOI：
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发表时间：
1991
期刊：
影响因子：
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通讯作者：
Z. Liliental
中科院分区：
文献类型：
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作者：
K. Yu;Z. Liliental
在低衬底温度（~ 200°C）下通过分子束外延生长的GaAs缓冲层中存在的过量As原子通过粒子诱导x射线发射测量为~ 4×1020原子/cm3。用离子通道法研究了这些多余As原子在层中的点阵位置。我们的结果强烈表明，多余的As原子位于靠近取代As原子的间隙位置，并在< 110 >通道中投射位移~ 0.3 a。这些结果与TEM结果显示的< 111 >分裂间隙模型一致。在600℃退火后，这些多余的As原子聚结形成As沉淀。
The excess As atoms present in as‐grown GaAs buffer layers grown by molecular beam epitaxy at low substrate temperature (∼200 °C) was measured by particle induced x‐ray emission to be ∼4×1020 atoms/cm3. The lattice site location of these excess As atoms in the layer was studied by ion channeling methods. Our results strongly suggested that the excess As atoms are located in an interstitial position close to the substitutional As atoms with a projected displacement ∼0.3 A into the 〈110〉 channel. These results are consistent with the 〈111〉 split interstitials model suggested from TEM results. After annealing at 600 °C these excess As atoms coalesce forming As precipitates.