Structural and magnetic characterization of Mn-doped ZnO films grown by spray pyrolysis method

Mn-doped ZnO films on Si substrate could be grown by the spray pyrolysis method at 500 degrees C under an air atmosphere. Although the orientation (0 0 0 2) peak intensity became small with increasing Mn concentration, the lattice constant of the c-axis expanded monotonously with increasing Mn concentration. This indicated that the Mn ion was understood to have occupied the Zn site without changing wurtzite structure. Furthermore, the magnetic signal which increased with decreasing temperature was presumably due to superparamagnetic clusters in the ZnO film because (chi - chi(0))(-1), chi and chi(0) represented the susceptibility and the temperature-independent paramagnetic contribution from the substrate, respectively, could be well fitted with the Curie law, giving almost zero Curie temperature. (C) 2007 Elsevier B.V. All rights reserved.