The growth of the ZnTe buffer layer in Si based CdTe affects the surface roughness and FWHM of the material.In this paper,in order to verify the influence of the growth parameters of the ZnTe buffer layer grown by the migration enhanced epitaxy (MEE) technology in the molecular beam epitaxy Si based CdTe on the surface roughness and FWHM of the composite substrate material,the main parameters involved in the MEE growth process including Zn to Te numerical ratio,MEE growth temperature,Zn and Te beam intensity value are investigated.Three sets of experiments are designed,and high resolution X ray diffractometer,white light interferometer and infrared Fourier spectrometer are used to test the growth results of the epitaxial film and the influence of MEE growth parameters on the quality of composite substrate materials is summarized.The optimal epitaxial process conditions are obtained by experiments to improve the material quality.