InSb-based high operation temperature InAlSb infrared detectors are the development direction of a new generation of infrared detectors. The study of surface oxide layers of detector substrates is the basis of the direction. Spectroscopic Ellipsometry (SE) and X-ray Photoelectron Spectroscopy (XPS) are used to analyze the surface oxide layers of the detector substrates grown by the existing processing. By selecting better corrosion liquid from common corrosion liquid, adjusting its ratio and adding inorganic acid, better surface oxidation treatment liquid is obtained. The stability of the surface oxide layer after treatment is compared and the variation of the main components is analyzed. Finally, the substrates which meet the parameters of surface oxide layers for Epi-ready InSb wafers are obtained. This work lays the foundation for subsequent study of high operation temperature detection components.