X-ray photoelectron spectroscopy studies on the bonding properties of oxygenated amorphous carbon nitride thin films synthesized by pulsed laser deposition at different substrate temperatures

Abstract

Oxygenated amorphous carbon nitride thin films (a-CN x O y ) were deposited by pulsed laser deposition of camphoric carbon (CC) target at various substrate temperatures (ST). The influence of ST on the bonding properties of a-CN x O y films was investigated. The nitrogen to carbon (N/C) atomic ratio and oxygen to carbon (O/C) atomic ratio, bonding state and microstructure of the deposited a-CN x O y films were characterized by X-ray photoelectron spectroscopy (XPS) and been confirmed using standard measurement techniques. The bonding states between the C and N, and C and O in the deposited films are found significantly influenced by the ST during deposition process. The N/C and O/C atomic ratio of the a-CN x O y films reached the maximum value at 400 °C. The XPS C 1s shows the bonding state of a-CN x O y films changes from diamond-like tetrahedral (sp 3) carbon and carbon (C–C) bonding to graphite-like trihedral (sp 2) C C bonding with the increase of ST. While, the XPS N 1s shows the sp 3 C–N bonds increases with higher rates compared with sp 2 C N bonds up to 400 °C, after which it decreases with higher ST. The C–N bonding of C–N, C N and C N were observed in the deposited a-CN x O y films.