A GROWTH-MODEL FOR THE CARBONIZATION OF SILICON SURFACES

The kinetics of carbonization of (111)Si by rapid thermal processing w ith C3H8 diluted in H-2 were investigated and compared with published results on (100)Si. A mathematical description for the saturation beha viour was developed and fitted with the data received by ellipsometry and atomic force microscopy. These parameters an nucleation density, s ilicon diffusion flux and a ratio between vertical and horizontal grow th. The model agrees in the estimation of saturation thickness and tim e as a function of concentration and temperature. A. boundary concentr ation around 0.1% was found where the surface is already sealed off af ter heating up. Above this concentration the model failed. (C) 1997 El sevier Science S.A.