An infra-red and secondary ion mass spectrometric study was made of diffusion in undoped, radio-frequency sputtered, multi-layered, hydrogenated or deuterated, amorphous material. The results indicated that the long-range motion of atomic H was suppressed when the micro-void content exceeded a critical value that was related to the initial SiH2 and SiH3 content. A marked power-law time dependence (exponent = 0.75) of the diffusion constant, when below the critical value of 7at%, was explained in terms of H migration involving mobile intrinsic defects and an exponential distribution of traps for H atoms or defects.

J.Shinar, R.Shinar, S.Mitra, J.Y.Kim: Physical Review Letters, 1989, 62[17], 2001-3