Diffusion of Boron in Silicon through Oxide Layer

The diffusion of boron into silicon through thermally grown oxide layers has been studied by an open tube diffusion technique. The experimental data are interpreted by a two boundary diffusion model, and diffusion constant of boron in silicon oxide is determined at several temperatures. The diffusion constant obtained at 1150°C is 1.2×10 -16 cm 2 /sec with an activation energy of ΔH=78 kcal/mol. An anomalous diffusion is observed at a high impurity vapour pressure and a series of experimental results suggests conversion of silicon oxide into a “glassy layer” of unknown composition.