Diffusion anneals were carried out at temperatures ranging from 20 to 270C in evacuated silica ampoules, using diffusion sources of elemental I or CdI2; both under saturated vapor pressure conditions. The concentration profiles were measured by using radiotracer/sectioning or secondary ion mass spectrometric techniques. It was found that the profiles comprised 4 sections (table 4). A computer analysis which was based upon the sum of 4 complementary error functions gave satisfactory agreement with the data. The fastest diffusing component furnished diffusivity values which agreed with previously published data, but the overall results indicated that I which was diffused into CdTe from the vapor was not suitable as a long-term stable dopant when sharp junctions were required.

E.D.Jones, J.Malzbender, J.B.Mullin, N.Shaw: Journal of Crystal Growth, 1994, 138, 279-84

Figure 16

Diffusivity of In in p-Type CdTe as a Function of Temperature

(hole concentration = a: 109 to 1010, b: 1016 to 2 x 1016, c: 1014 to 2 x 1014/cm3)