Properties of Al-doped copper nitride films prepared by reactive magnetron sputtering

Cu3N and Al x Cu3N films were prepared with reactive magnetron sputtering method. The two films were deposited on glass substrates at 0.8 Pa N2 partial pressure and 100 °C substrate temperature by using a pure Cu and Al target, respectively. X-ray diffraction (XRD) measurements show that the un-doped film was composed of Cu3N crystallites with anti-ReO3 structure and adopted [111] preferred orientation. XRD shows that the growth of Al-doped copper nitride films (Al x Cu3N) was affected strongly by doping Al, the intensity of [111] peak decreases with increasing the concentration of Al and the high concentration of Al could prevent the Cu3N from crystallization. AFM shows that the surface of Al x Cu3N film is smoother than that of Cu3N film. Compared with the Cu3N films, the resistivities of the Al-doped copper nitride films (Al x Cu3N) have been reduced, and the microhardness has been enhanced.