An investigation was made of diffusion into intrinsic n-type crystals which were doped with P to 5 x 1015/cm3, and into B pre-diffused extrinsic p-type crystals, by using a closed-tube diffusion technique. Profiles were determined by means of neutron activation and 72Ga radioactive tracer and sectioning techniques. The overall results for 900 to 1050C could be described by:

D (cm2/s) = 2.9 x 100 exp[-3.76(eV)/kT]

An observed increase in Ga diffusivity, with hole concentration, was explained in terms of a generalized monovacancy diffusion model in which the diffusion of ionized substitutional impurities was assumed to be controlled mainly by the concentration of vacancies of the opposite charge type.

J.S.Makris, B.J.Masters: Journal of Applied Physics, 1971, 42[10], 3750-4