Ni doped ZnO thin films for diluted magnetic semiconductor materials

Ni doped ZnO (Zn1 xNixO) thin films were grown on quartz substrates via magnetron sputtering deposition process with the Ni concentrations of 5, 10 and 20 at.% in the films. The effects of Ni doping level and post annealing on the structural and magnetic properties of Zn1 xNixO films were investigated by means of X-ray diffraction (XRD), alternating gradient magnetometer (AGM) and photoluminescence (PL). A higher magnetic moment was acquired from the annealed Zn1 xNixO film doped with 5 at.% Ni, which was attributed to a better preferred orientation from a primary phase Ni:ZnO in the film. A relatively more pronounced ZnO(002) peak observed from the Zn1 xNixO film doped with 5 at.% Ni indicated a good crystallinity of the film, which was attributed to a lower level of Ni content in the film as well as the Ni ions substituted for the Zn ions to form Ni:ZnO. A slight shift in ZnO(002) peak position for the 5 and 10 at.% Ni doped ZnO films could be due to the distortion of the ZnO lattice caused by the Ni ion substituents for the Zn ions. 2007 Elsevier B.V. All rights reserved. PACS: 75.50.Pp; 75.50.Ss; 75.70. I; 78.55. m