Type-II superlattice infrared detectors usually use mesa junctions to detect infrared radiation, in which the preparation process of metal electrodes is crucial. The control of physical etching and chemical etching on the morphology of superlattice detector electrode holes and the influence on the etching rate in the inductively coupled plasma (ICP) etching system are studied in depth. By adjusting parameters such as ICP ion source power, radio frequency power, and etching gas flow, the balance between physical etching and chemical etching in the etching system is broken, and the process control of the inclination angle of the electrode hole sidewall from 70° to 90° is achieved. This method can obtain smooth electrode hole sidewalls and suitable inclination angles, providing optimal deposition conditions for the growth of metal electrodes.