Diffusion experiments were performed on amorphous hydrogenated p-i-n diodes which were subjected to a constant or pulsed reverse electric field. Under a reverse field, the mean free path for the diffusion of interstitial H was enhanced by a factor of at least 4. The present results indicated that the enhancement was not due to the field-drift of charged H atoms, but rather to a reduction in the electronic carrier density under reverse bias. The carriers controlled the capture rate of interstitial H into Si-H traps and therefore controlled the lifetime and the mean free path for diffusion via interstitials.

P.V.Santos, N.M.Johnson, R.A.Street: Journal of Non-Crystalline Solids, 1993, 164-166[1], 277-80