A theoretical study of the photovoltaic parameters of inorganic solar cells based on ZnO/Cu2O and ZnO/CuO heterojunctions was carried out to improve the energy conversion efficiency. The influence of the thickness, charge carrier concentration and band gap of Cu2O and CuO films, as well as ZnO, on the photovoltaic parameters of solar cells has been studied. The simulation results showed that the efficiency of solar cells is significantly affected by the contact potential difference, the diffusion length of minority charge carriers, the amount of generated photocurrent and the recombination rate. The maximum efficiency of a solar cell based on ZnO/Cu2O was obtained equal to 10,63%, which is achieved with a band gap, thickness and charge carrier concentration in Cu2O equal to 1.9 eV, 5 μm and 1015 cm–3 and band gap, thickness and the concentration of charge carriers in ZnO is equal to 3,4 eV, 20 nm and 1019 cm–3, as well as the displacement of the edges of the conduction bands is 0.8 eV. For a solar cell based on ZnO/CuO, a maximum efficiency of 18.27% was obtained with a band gap, thickness and charge carrier concentration in CuO equal to 1.4 eV, 3 μm and 1017 cm–3, as well as a displacement of the conduction band edges of 0.03 eV. The obtained results of modeling solar cells can be used in the design and manufacture of inexpensive and efficient photovoltaic structures.
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