A new method for the passivation of IR (1.5 - 5.0 μm) photo diode surfaces is offered using a mix of heavy fullerenes (HFull-mix):C ₇₆ + C ₇₈ + C ₈₄ + C ₉₀ + ⋯Principal operational characteristics of the diodes are researched. It is shown that with such passivation the dark current of the photo diodes decreases 14 %. The Peltier effect on heterojunction semiconductor A ³B ⁵/HFull-mix is found.