Strain relaxation of CdTe(100) layers grown by hot‐wall epitaxy on GaAs(100) substrates
Strain relaxation of CdTe(100) layers grown by hot‐wall epitaxy on GaAs(100) substrates
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GaAs(100)衬底上热壁外延生长的CdTe(100)层的应变弛豫
DOI：
10.1063/1.346079
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发表时间：
1990
影响因子：
3.2
通讯作者：
H. Fujiyasu
中科院分区：
文献类型：
--
作者：
H. Tatsuoka;H. Kuwabara;Y. Nakanishi;H. Fujiyasu
通过光学性质测量、X射线分析和透射电子显微镜研究了热壁外延生长在GaAs（100）衬底上的CdTe（100）层的应变弛豫。从透射电子显微镜观察可以认为，由于晶格失配，大部分应变的弛豫发生在界面处。然而，在厚度超过0.7 μm的层中，仍有少量的应变，数量级为10−3，并且随着层厚度的增加而松弛。在厚度超过10 μm的层中存在4×10−4的残余应变，这是由于层和衬底的热膨胀系数不同。此外，对于厚度超过17 μm的层，由于内部应变而分裂的基态（n=1）和第一激发态（n=2）自由激子态首次通过光致发光和反射光谱被观察到。结果表明，所制备的CdTe薄膜具有良好的结晶性和应变均匀性。
The strain relaxation of CdTe(100) layers grown on GaAs(100) substrates by hot‐wall epitaxy was investigated by measurement of optical properties, x‐ray analysis, and transmission electron microscopy. It is considered from transmission electron microscopy observation that relaxation of most of the strain due to lattice mismatch occurred at the interface. However, a small amount of strain, of the order of 10−3, remained in layers thicker than 0.7 μm, and it was relaxed as the layer thickness increased. The residual strain of 4×10−4, which exists in layers thicker than 10 μm, was due to the difference between the thermal expansion coefficients of the layer and the substrate. Moreover, for layers thicker than 17 μm, split ground (n=1) and first excited (n=2) free‐exciton states due to internal strain have for the first time been observed by photoluminescence and reflectance spectroscopy. The results show that CdTe layers with excellent crystallinity and homogeneity in strain are obtained.