Plasma emission monitoring (PEM) controlled DC reactive sputtered ZnO:Al thin films

► DC reactive sputtered ZnO:Al thin films have been prepared using a Zn:Al metallic target and plasma emission monitoring (PEM) control system. ► The relationship between the optical, electrical and structural properties of ZnO:Al thin films is discussed. ► A modified formula for the figure of merit is introduced and used in determining the optimum TCO conditions for the ZnO:Al films.