The sur face passivation treatment of mercury cadmium telluride in frared detectors has a signi ficant impact on the device's dark current , uhich determines the device's detection per formance. In order to investigate the inhibitory effect of di f ferent grouth methods of sur face passivation layers on dark current , a molecular beam epitaxy system was used to grow mercury cadmium telluride material on a Si substrate.CTe/ ZnS passivation film layers were groun by magnetron sputtering and in-situ passivation methods , respectively. A variable area photovoltaic detector was prepared on HgCdTe material using semiconductor technology. By testing the dark current of devices with di f ferent passivation film layers, the relationship between zero bias resistance and area product (R, A) and the ratio of perimeter area (p/A) was analyzed.The result shous that Si-based mercury cadmium telluride devices with magnetron sputtering growth passivation layers exhibit signi ficant tunneling currents, while Si-based mercury cadmium telluride devices with in-situ passivation grouth passivation layers can more ef fectively suppress sur face leakage currents. By fitting the variation of the R. A factor of the device with the PN junction area , it can be seen that devices with in situ growth of passivation layers have better passivation ef fects. The preparation and testing of variable area devices can effectively and intuitively reflect device per formance.