Gas permeabilities in thermally grown silicon dioxide films

The permeability characteristics of six gases, argon, helium, oxygen, nitrogen, carbon dioxide and hydrogen, in thermally grown silicon dioxide films have been evaluated. By studying the dependence of permeabilities on temperature, pressure and molecular weigth, it has been established that the controlling mechanism of transport is viscous flow through micropores. This implies, contrary to what is commonly assumed, that gas permeabilities in thermally grown silicon dioxide films decreases with an increase in temperature, and suggests that annealing temperatures should be low for favorable gas fluxes.