Fabrication of ZnO and CuCrO2:Mg thin films by pulsed laser deposition with in situ laser annealing and its application to oxide diodes

In situ laser annealing used in pulsed laser deposition of ZnO and Mg-doped CuCrO2 transparent semiconductor films was shown to be effective in improving their electrical and crystalline properties. The X-ray diffraction analyses and electrical measurements of the film samples deposited on glass substrates revealed that the laser irradiation of films at an energy of approximately 30 mJ/cm2 at 266 nm with a repetition frequency of 20 Hz and pulse duration of 20 ns during the deposition resulted in electrical characteristics that were similar to those obtained in the case of depositions with substrate heating. The pulsed laser deposition technique for ZnO and CuCrO2:Mg semiconductor films was expanded with the assistance of in situ laser annealing to form multilayer structures intended for transparent p-n heterojunctions. Consequently, we fabricated a p-n junction in the structure of p-CuCrO2:Mg/n-ZnO/n+-ZnO on a glass substrate at room temperature. The resulting junction exhibited rectifying current–voltage characteristics and the multilayer thin films used to form the p-n junction exhibited an optical transparency of 70% in the visible region with a thickness of 0.4 μm.