Key Words:Nitrogen compounds;Copper compounds - Energy gap - Grain boundaries - Grain growth - Iron - Semiconductor doping - Thermodynamic stability;Columnar grain - Copper nitride - Cylindrical magnetron sputtering - Doped films - Fe-doped - Grain shapes - Mean-grain size - Preferred growth
Abstract:Fe-doped Cu<inf>3</inf>N films were prepared by cylindrical magnetron sputtering equipment at room temperature. The doping of Fe with the proper concentration results in a change in the preferred growth orientation from the Cu-rich plane (1 1 1) to the N-rich plane (1 0 0), which relates to the evolution of the surface grain shape from pyramid to sphere. Excessive doping of Fe is not favourable for the crystallization of Cu<inf>3</inf>N films. The cross-sections of the doped films with preferred growth orientations of [1 0 0] exhibit regular columnar grains. The variation between the lattice constant and the XPS results reveals that Fe probably replaces the position of Cu atoms in the lattice or is segregated in the grain boundaries. Weaker bonding of Cu-N results in a reduction of thermal stability for Fe-doped Cu<inf>3</inf>N films. And the incorporation of Fe can effectively modify the energy gap. According to the variations in the mean grain size, the peak of N1s and the energy gap, it is inferred that a doping limitation exists around 2.0 at%. © 2014 IOP Publishing Ltd.<br/>
Volume:47
Issue:18
Translation or Not:no
