Improving the Thermal Stability of Cu3N Films by Addition of Mn

Mn-doped Cu3N films were deposited by cylindrical magnetron sputtering equipment on the common glass at room temperature. The incorporation of Mn can change the preferred growth orientation from Cu-rich plane (111) to N-rich plane (100) due to the improvement of nitridation of Cu. The shrinkage of the lattice and the X-ray photoelectron spectroscopy results reveal that Mn should replace Cu atoms in the lattice or be segregated in the grain boundaries. The thickness of Mn-doped film is smaller than that of the pure one due to the less physisorption of N species among the columnar grains. The mean grain size and the energy gap become larger with increasing Mn concentration to 2.2 at.% and then decrease when the concentration of Mn is higher than 2.2 at.%. Notably, weak doping of 1.5 at.% Mn successfully promotes the decomposed temperature by ∼50 °C. According to the results of XRD and SEM for Mn-doped films annealed in vacuum, a possible decomposed mechanism with increasing the annealing temperature is proposed.