Transparent conductive ZnO films for solar cells applications: photoelectric and spectral properties

摘要

Optimization of transparent conductive and textured-dielectric coatings to increase the efficiency and reflectance control is very important for solar cell applications. The developed technique has allowed us to obtain Li doped ZnO films with high transparency and low dark conductivivity. Measurements of dark and photoconductivity were carried out over a wide frequency range (0-10~(10) Hz). Photoelectric property studies have shown that with Li doping, it is possible to achieve an essential increase of photoconductivity. This phenomenon can be used for development of solid-state photodetectors in the UV range (290-340 nm). The current-voltage characteristics, current-optical power sensitivity and kinetics of rise and decay times of slow and fast components of the photoresponse were studied. It was found that the dark current and photocurrent have different conductivity mechanisms: hopping mechanism of charge transfer in the Hubbard model impurity band for dark conductivity current and drift mechanism of charge transfer in the conduction band for photoconductivity current.