At temperatures encountered in thermal oxidation, silicon dioxide flows viscoelastically, A reduced-dimension, generalized boundary element method for modeling such a problem has been developed. A modified Kelvin's solution is used as the kernel; constant-velocity loading is chosen to operate with a wide range of stress relaxation times. Simulation results are reported for simple cases of focal oxidation.>

Thermal oxidation of silicon involves the diffusion of oxidant molecules from the gas-oxide interface to the oxide-silicon interface, and the transport of newly formed oxide away from the latter. Under suitable formulations these two processes can be shown to be boundary-value problems of harmonic and biharmonic nature. Based on these properties, a boundary integral equation method (BIEM) has been developed for modeling oxidation. This method achieves simplicity and efficiency by solving a two-dimensional problem using line integrals on the boundaries. The use of source distributions as intermediary solutions facilitates direct calculations of a wide variety of boundary parameters.