Amorphous thin films of silicon boron carbon nitride (SiCBN) were deposited in a multigun radio frequency magnetron sputtering system using reactive co-sputtering of silicon carbide (SiC) and boron nitride targets. Films of different compositions were obtained by varying the ratios of argon and nitrogen gas in the sputtering ambient. The films were annealed in dry oxygen ambient in the temperature range 300-900 degrees C. Subsequent surface characterization of the annealed films was performed using X-ray photoelectron spectroscopy to investigate the chemical composition and oxidation kinetics at the different annealing temperatures. Studies revealed that the carbon and nitrogen concentrations in the films are highly sensitive to annealing temperatures. Higher annealing temperatures lead to broken C-N bonds, resulting in the loss of C and N content. Temperatures beyond 700 degrees C lead to complete loss of nitrogen, and the silicon and boron in the films interacted with oxygen to form SiO2 and B2O3. (C) 2007 The Electrochemical Society.