Characterization of thin film optic properties of Zn O:Al on glass substrate for solar cell window

It has been characterized a ZnO:Al thin film growth using sputtering technique for solar cell window. The aims of this research is to get a ZnO:Al thin film that can be used as a TCO (Transparent Conducting Oxide) on amorphous silicon solar cell. To get an optimum properties, deposition process has been done for various parameters, such as composition/concentration of Al, substrate temperature, gas pressure and deposition time. Based on experiments result, it's found that the optimum result was achieved at temperature 450 °C, gas pressure 6 x 10^-2 torr and time 1,5 hours. From optical properties (transmittance) measurements using UV-vis, it was found that the optimum results was achieved at temperature 450 °C. At this conditions, wave length (500-800) nm, the transmittance was (50-82) %, at pressure 6 x 10^-2 torr the transmittance was (50- 80) % and at deposition time 1,5 hours was (49-81) %. For ZnO thin film, was at wave length (500-800) nm, the transmittance was (78 - 80) %. From micro structure analysis using SEM, it was found that the thickness layer of ZnO was 1.5 μm and 1.3 μm for ZnO:Al. While from surface morphology it was found that for ZnO thin layer the grains was distributed homogeneously, while for ZnO:Al the grains was distributed unhomogeneously. (author)