X-ray spectroscopic study of the electronic structure of boron carbonitride films obtained by chemical vapor deposition on Co/Si and CoO x /Si substrates

Abstract

Boron carbonitride films are synthesized by chemical vapor deposition from a mixture of triethylamine borane and ammonia on a metallic or oxidized cobalt sublayer sprayed over Si(100) substrates. Scanning electron microscopy shows that the surface of a BCxNy/Co/Si sample has a homogeneous fine-grained structure; filamentous entities are found on the surface of the BCxNy/CoOx/Si sample. The electronic structure of the films is investigated by X-ray photoelectron spectroscopy (XPS) and near-edge X-ray absorption fine structure spectroscopy (NEXAFS). An analysis of the spectra shows that BCxNy films are composed of graphite and hexagonal boron nitride (h-BN) regions and complex BCxNyOz components with B-C, N-C, B-O, N-O, and C-O bonds. The deposition of the BCxNy film on the oxidized Co sublayer results in an increase in the number of C-O, N-O, B-O, and C-N bonds and a decrease of the graphite and h-BN components and in the number of C-B bonds. The XPS data are used to estimate the surface elemental composition of the BCxNy/CoOx/Si sample. It is found that the film consists of 66 at.% graphite component and 3 at.% h-BN; the proportion of complex C0.46B0.11N0.05O0.38 components is 31 at.%.