Correlation of deposition and IR properties of amorphous carbon nitride films

Abstract

The nitrogen-doped amorphous carbon film becomes infra-red-active when a nitrogen atom substitutes for carbon atoms in a graphite ring. It shows a broad active band in the range 1100–1900 cm−1, which is quite similar to its Raman spectrum and CN triple stretching peak that is around 2200 cm−1. In this study, a set of amorphous carbon nitride (a-C:N) films with different sputtering parameters was analyzed by a grazing-angle IR spectrometer. The IR spectra of a-C:N thin films are sensitive to changes in sputter parameters, such as the percentage nitrogen in the carried gas, flow ratio, power and the thickness of the carbon layer. A comparison of IR data to the ESCA analysis implies that nitrogen atoms are incorporated in the graphite ring in different modes or conformations as the sputtering parameters are changed.