A closed-tube technique and radiotracer sectioning methods were used to study the diffusion of 32P in intrinsic and extrinsic material (table 83). It was found that the P diffusivity increased by a factor of about 10 with respect to the value for intrinsic material, in the case of the highest P content used. At between 950 and 1200C, the diffusivity of P could be described by:

intrinsic: D(cm2/s) = 5.3 x 100exp[-3.69(eV)/kT]

extrinsic: D(cm2/s) = 3.9 x 10-1exp[-3.12(eV)/kT]

The results were explained by assuming that the diffusion process was controlled mainly by monovacancies in the singly negatively charged state.

Phosphorus Isoconcentration Diffusion Studies in Silicon. J.S.Makris, B.J.Masters: Journal of the Electrochemical Society, 1973, 120[9], 1252-5