An investigation was made of the effects of F upon B diffusion in thin films which were used for metal-oxide semiconductor structures. Secondary ion mass spectroscopy was used to measure the B penetration profile, from p+-type polycrystalline Si into a Si substrate (via the oxide film), for various F doses. Experimental and simulated results were compared in order to determine the B diffusion coefficients in the oxide. It was found that the diffusion coefficients exhibited an Arrhenius behavior for each F dose. The diffusion coefficients at a F dose of 1016/cm2 were 30 times larger than those for no F dose. At a F dose of 1015/cm2, the diffusion coefficients were 5 times larger.

Effect of Fluorine on Boron Diffusion in Thin Silicon Dioxides and Oxynitride. T.Aoyama, K.Suzuki, H.Tashiro, Y.Toda, T.Yamazaki, K.Takasaki, T.Ito: Journal of Applied Physics, 1995, 77[1], 417-9