XRR and SAXS Study of Hydrogenated Amorphous Silicon Oxycarbide (a-SiOC:H) Films

Abstract

Thin films of hydrogenated silicon-oxycarbide (a-SiOCx:H) have largely replaced pure silicon oxide films as back end of line (BEOL) processing in Ultra Large Scale Integrate Circuit (ULSI). A single chamber system for hot wire chemical vapor deposition (HWCVD) was employed to deposit different films of a-SiOCx:H with 0.5 < x < 0.8. All films were characterized by infrared spectroscopy and X-ray photoelectron spectroscopy (XPS) to determine the stoichiometry and the presence of various bonding configurations of constituent atoms. We used X-ray reflectivity (XRR) and Small angle X- ray scattering (SAXS) to determine the porosity and inhomogeneities (clustering) in the films.