High-Performance Semitransparent Photodiodes Based on Zinc Oxide/C60/Copper Phthalocyanine Double Heterojunction

Photovoltaic devices based on metal oxide and organic semiconductor heterostructure generally exhibit poor performance due to inefficient exciton dissociation at the metal oxide/organic interface. Here, we present an enhancement in the performance of photodiodes fabricated via zinc oxide (ZnO)/C60/copper phthalocyanine (CuPc) double heterojunction solution. This obtained photodiode demonstrates photodetection in the wavelength range of 400-850 nm with high photoresponsivity (R), specific detectivity ( {D}^{\ast } ), and transparency. Remarkably high R of 9040, 64.0, and 2.0 A/W and {D}^{\ast } of 1.32\times 10^{{15}} , 2.86\times 10^{{12}} , and 1.10\times 10^{{11}} Jones were achieved, for representative wavelengths of 405, 650, and 850 nm, respectively. The device exhibited a maximal average, transparency of 0.444 in the wavelength range of 400-1000 nm. Investigation into the effects of C60 layer thickness ( {d}_{\text {C60}} ) revealed a strong dependence of both R and {D}^{\ast } on {d}_{\text {C60}} . For shorter wavelengths (405 and 450 nm), the maxima of {R} \sim {d}_{\text {C60}} curves were observed around {d}_{\text {C60}} =10 nm, whereas for longer wavelengths (532, 650, and 850 nm), they appeared at around {d}_{\text {C60}} =5 nm. The maxima of {D}^{\ast } \sim {d}_{\text {C60}} curves were consistently located at {d}_{\text {C60}} =5 nm for all measured wavelengths. Further investigations on the impact of CuPc layer thickness ( {d}_{\text {CuPc}} ) i