Effect of oxygen to argon flow ratio on the properties of Al-doped ZnO films for amorphous silicon thin film solar cell applications

Transparent conductive oxide thin films in solar cell fabrication have attracted much attention due to their high conductivity and transmittance. In this paper, we have investigated the aluminum-doped zinc oxide (AZO) thin films prepared by radiofrequency magnetron sputtering on Asahi U-type SnO2 glass with different O2/Ar flow ratios in vacuum chamber. Furthermore, the micro-structural, electrical, and optical properties of AZO/SnO2 films were studied. The change in O2/Ar flow ratios is found to significantly affect the haze value, and slightly affect electrical resistivity and transmittance of the films. Afterward, the fabricated AZO thin films with different O2/Ar flow ratios were used for building the solar cell devices. The current–voltage and external quantum efficiency characteristics were investigated for the solar cell devices. The optimized O2/Ar flow ratio of 3 for solar device shows the best efficiency of 10.41%, and a 20% increase in short-circuit current density compared to typical Asahi solar cells.

► A thin Al-doped zinc oxide (AZO) film has been deposited on SnO2 substrates.
► The AZO film deposited at an O2/Ar ratio of 3 shows low resistivity and high haze.
► The AZO film contains tiny grains that enhance light scattering.
► The amorphous silicon solar cell with the AZO layer shows a 20% increase in Jsc.