J. Phys. IV France 09 (1999) Pr8-265-Pr8-271
Study of the growth mechanisms of low-pressure chemically vapour deposited silica filmsF. Ojeda1, R. Cuerno2, R. Salvarezza3 and L. Vázquez1
1 Instituto de Ciencia de Materiales de Madrid, CSIC, Cantoblanco, 28049 Madrid, Spain
2 Departamento de Matemáticas y Grupo Interdisciplinar de Sistemas Complicados, Universidad Carlos III de Madrid, Av. Universidad 30, 28911 Leganés, Spain
3 INIFTA, Sucursal 4, Casilla de Correo 16, 1900 La Plata, Argentina
We have studied the surface morphology evolution of SiO2 films grown at 20 nm/min in a low-pressure chemical vapour deposition reactor from SiH4/O2 mixtures at low (611 K) and high (723 K) temperatures. Films have been deposited for times ranging from 10 min up to 48 hours. It is shown that the SiO2 growth at high temperature becomes stable, whereas at low temperature it is unstable (i.e., the surface roughness increases continuously with deposition time). This clear difference is explained on the basis of the different growth mechanisms operating under both experimental conditions. These results are compared with the predictions of the few theoretical works on growth evolution by chemical vapour deposition.
© EDP Sciences 1999