Secondary ion mass spectroscopy was used to measure the diffusion of deuterium in hydrogenated amorphous silicon. For a film deposited in a dc glow discharge in SiH4 at a substrate temperature of 315C, the diffusion data obeyed:

D(cm2/s) = 1.17 x 10-2exp[-1.53(eV)/kT]

This result implied that degradation of these films due to hydrogen out-diffusion at 100C would not be significant until after more than 104 years

A SIMS Analysis of Deuterium Diffusion in Hydrogenated Amorphous Silicon. D.E.Carlson, C.W.Magee: Applied Physics Letters, 1978, 33[1], 81-3