Effects of low-temperature annealing on Ohmic contact of Au/p-CdZnTe

Effect of annealing time at 333 K in air on the ohmic property of Au/p-CdZnTe contact was studied. Through I–V measurement, it was found that Au/p-CdZnTe had excellent ohmic property after 2 h annealing. SEM and XPS analyses showed that Au atoms diffused into CdZnTe during annealing. Diffused Au did not form any compound with any element in CdZnTe, but replaced Cd sites or occupied Cd vacancy as acceptors. Thus, the heavy p-type doping layer was formed and M-p+-p ohmic contact was obtained. At the same time, about 27.01% of Te in un-deposited CdZnTe surface layer was oxided into TeO2 during 2 h annealing.