A diffusion potential was proposed for 2 different materials and their interface. An interfacial impurity flux model was derived by using this potential. The flux model was related to measurable physical parameters; such as diffusion coefficients in the 2 materials, and segregation coefficients. This model also included the transport segregation coefficient, which had to be determined experimentally. This theory was applied to the profiles of B which was diffused from polysilicon into Si. The concentration discontinuity at the polysilicon/Si interface appeared clearly in time. This was explained by the present interfacial impurity flux model. The segregation transport coefficient was deduced to be 5 x 10-6cm/s.

K.Suzuki, T.Fukano: Journal of the Electrochemical Society, 1991, 138[1], 230-3