Carbon nitride — prospects for ultimate performance of superhard materials

In order to deposit thin solid films containing covalently bonded carbon nitride as a major matrix component, several different techniques for deposition were explored. They included reactive pulsed laser deposition, reactive DC magnetron sputtering and laser ablation of a frozen ethanol/liquid N2 double layer system. Surface analysis techniques showed that the concentrations of nitrogen were as high as 20 to 25 at% in the bulk and up to 40 at% in the upper layers of the resulting a-Ca-CNx films. The covalent bond of nitrogen to carbon was identified. It is similar to the nitrogen bonds in silicon nitride and boron nitride.