Effect of N2-gas flow rates on the structures and properties of copper nitride films prepared by reactive DC magnetron sputtering

Copper nitride films were deposited on glass substrates by reactive DC magnetron sputtering at 100 °C substrate temperature. The influence of N2-gas flow rates on the structure, resistivity and microhardness of deposited films was investigated. X-ray diffraction measurements showed that the films were composed of Cu3N crystallites with anti-ReO3 structure and exhibited preferential orientation to the [111] and [100]. The preferred crystalline orientation of the films changed with the N2-gas flow rate, which should caused by the variation of Cu nitrification rate with N2-gas flow rate. Additionally, the N2-gas flow rate also affected the deposition rate, the resistivity and the microhardness of the Cu3N films. The optimum N2-gas flow rate for producing high-quality and well-oriented Cu3N films on glass substrates is 5–10 sccm, where the substrate temperature is 100 °C and the DC power is 50 W.