The diffusion of D in films was studied, at temperatures of between 485 and 655K, by using a D2 gas-phase permeation technique. It was found that the diffusivity ranged from 5.8 x 10-14 at 485K to 5.1 x 10-13cm2/s at 655K. The overall results could be described by:

D (cm2/s) = 1 x 10-10 exp[-0.34(eV)/kT]

Grain-boundary diffusion through thin films was suggested to be the rate-limiting process.

R.Checchetto, L.M.Gratton, A.Miotello, C.Tosello: Journal of Non-Crystalline Solids, 1997, 216, 65-70