The diffusion of O into SiO2-encapsulated polycrystalline CdSe films was investigated at 350 to 500C by using secondary ion mass spectrometry. The O profiles in the SiO2 indicated that both isotopic O exchange and the diffusion of molecular O along short-circuit paths occurred with activation energies of 1.1 and 0.66eV, respectively. The activation energies determined for the diffusion of O in the grains (0.39eV) were smaller than the values determined for diffusion in the grain boundaries (0.70eV), and was attributed to impurities and intrinsic defects accumulating at the grain boundaries.

Oxygen and Indium Diffusion into SiO2 Encapsulated Polycrystalline CdSe Films. R.M.Langford, M.J.Lee, S.W.Wright, C.P.Judge, R.J.Chater, T.J.Tate: Journal of Electronic Materials, 2001, 30[8], 925-30