Light trapping properties of surface textured ZnO:Al films deposited at various working pressures

Surface textured ZnO:Al (AZO) films with good optoelectronic and light trapping properties were prepared on glass substrates by direct current pulse magnetron sputtering followed by a wet chemical etching process in NaOH solution (5 wt%) at room temperature. The influence of working pressure on different properties of AZO films including etching rate, structural and optoelectronic properties, light trapping ability as well as etching behavior was studied in detail. Different surface features were observed with the increasing of working pressure. The relationship between surface textured structure and working pressure was discussed. The etched AZO film deposited at 0.8 Pa exhibited uniformly and distinctly crater-like surface textured structure, which is an effective textured surface for light trapping. Correspondingly, for the etched AZO film deposited at 0.8 Pa, high visible optical transparence, electrical conductivity and haze value were also achieved. (C) 2015 Elsevier Ltd and Techna Group S.r.l. All rights reserved.