In situ control of SiOx composition by spectroscopic ellipsometry

This paper presents a study on the growth of SiOx thin films deposited by electron gun evaporation of SiO under O2 reactive atmosphere. The composition x of the films was determined by spectroscopic ellipsometry using the random bonding model (RBM) provided that the parameters used in the original model of Aspnes and Theeten [J. Appl. Phys. 50 (1979) 4928] were adapted to the growth conditions. The composition depended mainly on the flux ratio of the species arriving on the surface. This model had to be slightly modified to take into account the composition of the films evaporated without oxygen, exhibiting a x value of 1.2 instead of 1, and the incorporation of O2 in the growing film.