Wet corrosion process of p-type contact hole of HgCdTe chip was studied,and the p-type contact holes of HgCdTe were prepared by wet etching under different conditions.The surface morphology of the holes was analyzed by scanning electron microscope (SEM),laser scanning microscope (LSM),and the electrical performance of the sample was characterized by the current-voltage curve characteristic.The experimental results show that the conventional wet etching process has some problems such as serious drilling erosion and poor uniformity.So,in the paper,an ultrasonic assisted wet corrosion process was proposed to prepare p-type contact holes with good morphology and uniformity.