ALD of in-doped ZnO

Atomic layer deposition (ALD) windows for ZnO and ZnS films using DEZn, H2S and H2O as precursors were determined and the deposited films were characterized. Doping of ZnO with In during ALD by periodic exposure to TMIn was studied with an emphasis on the structural properties of the films. XRD results show compressive stress in the film induced by the larger In atom, which leads to smaller grain size. Based on these results stacked layers of ZnOS/ZnO:In and sputtered ZnOS/ZnO:Al were deposited on CIGS thin films to compare the performance of the ALD TCO to that of our standard TCO. The finished cell with ZnO:In as TCO shows relatively low Jsc and Rse compared with the cell using sputtered ZnO:Al as TCO.