Large room temperature magnetoresistance of transparent Fe and Ni doped ZnO thin films

Abstract

The electrical, optical, and magnetic properties of pure, 1%Fe, and 1%Ni doped ZnO thin films grown by spray pyrolysis technique were studied. All samples are transparent (T ≈ 85%) in VIS and near infrared region of wavelength. Ni and Fe doped ZnO layers are paramagnetic. Resistivity versus temperature has semiconducting behavior. Large value of magnetoresistance at 300 K at 1.3 T: MR = 56%/T for 1%Fe doped ZnO and MR = 28%/T for 1%Ni doped samples have been observed. These exceptional values of MR at room temperature originate probably from hopping conductivity in polycrystalline diluted magnetic semiconductor in paramagnetic high dilution limit.