OXYGEN REDISTRIBUTION DURING DIFFUSION IN THIN SILICON LAYERS

During diffusion processes in thin solid layers, the usual assumption of a semi-infinite solid with constant bulk concentration is not valid . The well-known solution of the diffusion equation, based on compleme ntary error functions, is therefore not applicable, and numerical solu tions are normally used. In this work, we report an analytical solutio n for impurity redistribution by diffusion in thin layers. We compare the results of an explicit application of this analytical solution to oxygen out-diffusion in silicon-on-oxide structures with the experimen tal data, and discuss the limits of its applicability.