Studies on the Pressure-dependency of the Diffusion of Iodine into CdTe

An investigation on the pressure dependency of the diffusion of iodine into CdTe at temperatures of 220°C, 360°C and 500°C is reported The diffusion profiles were found to be composed of four components which were characterised by effective diffusivities D₁, D₂, D₃ and D₄. For each component the diffusivity remained constant indicating that the diffusivity was independent of the CdI₂ pressures except at low pressures at 500°C. In the case of the corresponding surface concentrations, C_o, initially each component showed a decrease, went through a minimum and increased sharply before either gadually falling again or becoming constant as the CdI₂ pressure was reduced systematically. These features are discussed in this paper.