Deuterium permeation through SiO2 thin film deposited on stainless steel substrate

The diffusivity of deuterium in low temperature deposited silicon oxide thin films has been studied in the temperature interval from 485 to 655 K using a D-2 gas phase permeation technique. The measured deuterium diffusion coefficient varies from (5.8 +/- 2.0) x 10(-14) cm(2)/s at 485 K to (5.1 +/- 1.8) x 10(-13) cm(2)/s at 655 K and has an activation energy of 0.34 +/- 0.02 eV in the entire temperature range with a pre-exponential factor of the order of 10(-10) cm(2)/s. Grain boundary diffusion through the polycrystalline silicon oxide thin film is suggested to be the rate limiting factor in the deuterium transport process. (C) 1997 Elsevier Science B.V.