Slow positron beam study of hydrogen ion implanted ZnO thin films

•Hydrogen introduced by ion implantation can form hydrogen-related defect complex.•VZn+OH defect complex is identified by positron annihilation and IR spectroscopy.•Irradiation defects suppress the luminescence process.

The effects of hydrogen related defect on the microstructure and optical property of ZnO thin films were investigated by slow positron beam, in combination with x-ray diffraction, infrared and photoluminescence spectroscopy. The defects were introduced by 90 keV proton irradiation with doses of 1×1015 and 1×1016 ions cm−2. Zn vacancy and OH bonding (VZn+OH) defect complex were identified in hydrogen implanted ZnO film by positron annihilation and infrared spectroscopy. The formation of these complexes led to lattice disorder in hydrogen implanted ZnO film and suppressed the luminescence process.