Thin Film Zn-Mg-Al-O Produced by r. f. Sputtering Used in Antimony Sulfide Solar Cells

Abstract

© 2018 by the Authors. Zn 0.80 Mg 0.17 Al 0.0 3O (AZMO) thin film of 180-200 nm in thickness was produced by radio frequency (r. f.) argon-ion sputtering from commercial ZnO:Al and Mg-metal targets with 150 and 200 W of applied r. f. power. AZMO film is of bandgap 3.62 eV, compared with 3.25 eV for Zn 0.96 Al 0.04 O (AZO) film. The electrical conductivity (s) of AZO film is 80 -1 cm -1 , which reduces to 0.2 -1 cm -1 when the film was heated in air at 300°C. For AZMO film these values are, 10 and 10 -4-1 cm -1 , respectively. Thus, the AZMO film is converted to a high resistive transparent n-type film for solar cell. Such films on F-doped SnO 2 (FTO) film was used in antimony sulfide solar cell: FTO/AZMO/Sb2S3/C-Ag. This cell showed notable increase in the short circuit current density (10.86 mA/cm 2 ) with respect the solar cell, FTO/CdS/Sb2S3/C (6.28 mA/cm 2 ). The increase is due to improved external quantum efficiency toward the ultraviolet region. The open circuit voltage of these cells are 0.478 V and 0.627 V, respectively, with conversion efficiencies of 1.3% and 1.13%.