COMPUTER-SIMULATION OF HIGH FLUENCE OXYGEN PROFILES IN SILICON

A fast computer programme has been developed to calculate high fluence oxygen distributions after implantation into unmasked silicon or through masking oxide layers. Using a TRIM-profile to represent the incremental fluence distribution, the oxygen redistribution due to swelling, sputtering and diffusion is calculated. The results show that for substoichiometric fluences the peak of the high dose profile is moving downwards for unmasked and upwards for masked silicon, due to swelling being the dominant process in the first case and sputtering being the dominant process in the latter case. Once a buried SiO2layer is formed the upper interface is always moving upwards, the lower one always downwards, but interface velocities and shapes strongly depend on the existence of a masking layer. © 1990.