In this paper, the PAD used in infrared detector chips is investigated. Although many domestic and foreign infrared detector manufacturers, research institutes have published their own electrode system, but for the design of the electrode is rarely mentioned, for the electrode system of the thickness of each layer of the film design is even rarer. An electrode system is designed by analyzing the physical properties of commonly used electrode materials and the validation test results show that this electrode system does not affect the performance of the device and can meet the reliability requirements of the device.