Effect of Substrate Temperature on the Optical Properties of SnxSey/ZnO:Al P-N Junction Solar Cell

Abstract

Zinc Oxide was doped with various percentages of Aluminum ranging from 0% to 10% by mass. Tin (Sn) and selenium (Se) metal samples were mixed in different ratios of increasing selenium. Deposition of both SnSe and ZnO:Al thin films on glass substrate was done by a method of evaporation using Edwards Auto 306 RF/DC Magnetron evaporation system under the following conditions; deposition temperature 500K, pressure of 3.5×10-5 millibars and a current of 3.5A. Transmittance and reflectance data in the range 300nm-1500nm was obtained using a double beam solid spec 3700 UV-VIS-NIR shimadzu spectrophotometer. Doping of 5% aluminium and a synthesized ratio of 1:1.0 for ZnO:Al and SnSe thin films respectively was obtained as the optimum values. The optimized Al doped ZnO was deposited at different deposition temperature ranging from 350K-550K. Transmittance percentage in the visible region was used to optimize deposition temperature and 510K was obtained as the optimum value. Band gap energies of optimized ZnO:Al and SnxSey was found to be 3.61±0.05 eV and 1.37±0.05 eV respectively.