Impurity doping and compensation mechanisms in CdTe

Abstract A short theoretical analysis of the main mechanisms governing the efficiency of impurity doping in CdTe is first presented. Then doping experiments with donor (Al, In, Cl, Br, I) and acceptor (N, As) impurities are reviewed. It has been shown that uncompensated n-type and p-type doping up to a limit in the range 10 17 –10 19 cm −3 , depending on the element, can be achieved under proper conditions of incorporation. The implication of impurities in the fabrication steps of CdS/CdTe solar cells, including the CdCl 2 treatment, is briefly discussed. Finally, the present state of knowledge about particular native point defects in tellurium-saturated CdTe ( V Cd , Te Cd ) is examined.