Oxide films, deposited onto Si by atomic layer chemical vapor deposition, were annealed in an 18O-enriched O atmosphere under various conditions. Cavity formation at the film surface was monitored by atomic force microscopy, and was found to depend upon the annealing parameters. The areal densities and profiles of O incorporated from the gas phase were determined by using nuclear reaction techniques. A propagating front of incorporated O from the gas/solid interface and towards the film/substrate interface was observed. This was modeled as a diffusion-reaction process, in which isotopic exchange was the reaction channel. The model reproduced the observed 18O profiles and areal densities, and their dependence upon the annealing parameters.

Diffusion Reaction of Oxygen in Aluminum Oxide Films on Silicon. E.B.O.da Rosa, I.J.R.Baumvol, J.Morais, R.M.C.de Almeida, R.M.Papaléo, F.C.Stedile: Physical Review B, 2002, 65[12], 121303 (4pp)