Mg-doped SnO2 properties modulation applied to all-sputtered CdTe solar cells

Abstract

Mg-doped SnO2 (MTO) is a material with optical, electrical, morphological, structural and chemical properties that are modulated as a function of the doping level. This quality makes it an optimal material for different applications such as sensors or photovoltaic devices. In this work a complete and extensive range of MTO thin films doping levels was studied, obtaining Mg atomic concentration from 0 to 23 %, band gap from 3.2 to 3.8 eV, and transmittance of ∼ 96 %. Furthermore, RF-sputtering technique with a single Tin target and Mg shavings was used to obtain MTO thin films with modulable doping and parameters, a novel process to reduce costs versus other techniques. MTO was applied as a window layer in thin film solar cells, obtaining a maximum power conversion efficiency of 8.23 % for CdTe all-sputtered.