Relationship between lattice parameters and compositions of molecular beam epitaxial Hg1- x CdxTe films
Hg1－xCdxTe分子束外延薄膜晶格参数与组分关系的研究

High-resolution x-ray diffraction technology is applied to the measurement of lattice parameters and the study of strain for Hg_ 1-xCd_xTe films grown by molecular beam epitaxy. The results show that there exist both perpendicular strain and shear strain in Hg_ 1-xCd_xTe films. Based on crystal elastic theory, strain states in Hg_ 1-xCd_xTe films are analyzed and calculated, and the lattice parameters of Hg_ 1-xCd_xTe films at the relaxation state are obtained. It is found that the relationship between lattice parameters and compositions of Hg_ 1-xCd_xTe films agrees with Vegard's law, rather than Higgins formula proposed in earlier research. It is also found that the lattice parameters can be derived from the measured data of (224) plane spacing, and that the compositions of Hg_ 1-xCd_xTe films can also be evaluated by using Vegard's law with an error about 0.01.