Based on the fabrication technology of MW HgCdTe,the recent research progress on molecular beam epitaxy growth of SW HgCdTe on Si composite substrate is reported.Through the original temperature calibration,the use of in situ measurements such as RHEED and pyrometry,the temperature controlling figure profile of MW MCT,a customized temperature controlling figure profile for SW MCT was built and optimized.The defects density of optimized Si based SW HgCdTe is less than 3000 cm-2 and the surface is smooth and uniform.SW/MW dual band HgCdTe has been also fabricated based on this technology.