Magnetic, optical and electrical properties of Mn-doped CuCrO2 thin films prepared by chemical solution deposition method

CuCrO2 and CuCrO2:Mn thin films were prepared on sapphire substrates by chemical solution deposition method. The effects of the annealing temperatures and Mn concentration on the structural, electrical and optical properties were investigated. The X-ray diffraction measurement was used to confirm the c-axis orientation of CuCrO2 and CuCrO2:Mn thin films. The maximum transmittances of the films in the visible region are about 65% with direct band gaps of 3.25 eV. All films showed the p-type conduction and semiconductor behavior. The electrical conductivity decreases rapidly with the increase of Mn content, the maximum of the electrical conductivity of 1.35 × 10−2 S cm−1 is CuCrO2 film deposited at 600 °C temperature in 10−3 Torr vacuum, which is about four orders of magnitude higher than that of the Mn-doped CuCrO2 thin film. The energy band of the samples is constructed based on the grain-boundary scattering in order to investigate the conduction mechanism. Moreover, the samples exhibit a clear ferromagnetism, which was likely ascribed to originating from the double-exchange interaction between the Mn3+ and Cr3+ ions.