Research of the photoelectric parameters of ZnO/Cu2O heterojunction solar cells

Theoretical modeling of ZnO/Cu₂O heterojunction solar cells has been carried out to optimize its structure and increase the energy conversion efficiency. The effect of the thickness and defect concentration in Cu₂O and ZnO layers on the efficiency of a solar cell is studied. It was found that the optimal thickness of the Cu₂O and ZnO layers should be 5 µm and 20 nm, respectively. It is shown that to obtain a high efficiency of a solar cell, the defect concentration (copper vacancies) in the Cu₂O layer should be 10¹⁵ cm⁻³, and the defect concentration (oxygen vacancies) in the ZnO layer should be 10¹⁹ cm⁻³. The maximum efficiency of a solar cell based on ZnO/Cu₂O is 6 %. The experimental formation of Cu₂O and ZnO layers by magnetron sputtering at room temperature has been carried out, their surface morphology has been studied, and experimental samples of oxide solar cells have been created.