Published online by Cambridge University Press: 28 February 2011
Variations in refractive index (density) with growth temperature are taken as a rough measure of residual compressive stress in dry SiO2 films. This paper presents experimental data regarding the relaxation of these stresses by a low-temperature (600–900°C) oxygen corona discharge process. For an initial oxide layer of 1100 Å thickness grown at 800°C, relaxation is complete after a corona treatment of 10 minutes at -lμA. The dose of O− ions required is found to be about 1–1.5% of the total oxygen atoms in the initial layer. The difference in dose between oxide on (111) and (100) Si is found to be proportional to the respective density changes from the initial oxide to fully relaxed oxide.