Sputtering Deposited CuCrO2 and CuCrO2-ZnSnN2 Heterojunctions

There has been no experimental work on CuCrO2-ZnSnN2 heterojunctions (HJs), though theoretical work shows that their photoelectric conversion efficiency is around 20%. Here, CuCrO2 thin films and p CuCrO2-n ZnSnN2 HJs are prepared by varying the sputtering power of the Cu-Cr alloy target while the other parameters are held constant. The as-deposited CuxCryOz thin films are amorphous, with CuCrO2 as the major phase. The CuCrO2 thin films are p-type conductive, with an optical band gap of about 3.64–3.84 eV. The ZnSnN2 thin films are wurtzite and n-type conductive. The dark current density J versus voltage V curve measurements show that all the HJs showed rectification, while only the samples deposited at 40 and 50 W had a photo-induced current. Further analysis shows the HJs deposited at 40 W have the lowest shunt conductance, saturation current density, and trap density, implying an effect of fabrication conditions on the properties of HJs.