It was pointed out that CdTe thin films tended to suffer from poor electrical contact, due to the non-availability of a contacting material with a large work function for proper matching with p-type CdTe. The basic problem was the method of doping of the thin film. One solution was the formation of a p+ layer, on the CdTe surface, by the reaction or in-diffusion of dopants. Another approach was to alter the barrier height, before metal contact deposition, by depositing a layer of Cu-doped ZnTe. A method was presented here which could overcome some limitations of the other methods. By using an autocatalytic reduction process, Ni-P composite material was deposited onto the p-type CdTe surface. Upon annealing at 250C, the contact resistivity decreased to between 0.1 and 0.08Ωcm2. It was shown that the decrease in the resistance was due to the diffusion of P into the CdTe; with the formation of a p+ layer.

B.Ghosh, S.Purakayastha, P.K.Datta, R.W.Miles, M.J.Carter, R.Hill: Semiconductor Science and Technology, 1995, 10[l], 71-6