Photoluminescence Spectroscopy Study Of Impurities And Defects In Ion-implanted ZnO Single Crystal

The development of semiconductor materials is the cornerstone of the progress of social productivity.As a new type of semiconductor materials,ZnO has great application potential in the field of photoelectric devices due to its excellent performance.But the existence of large number of intrinsic point defects in ZnO makes its luminescence behavior very difficult to summarize which greatly hampers the development of ZnO related optoelectronic devices.Therefore,it is important to study mechanism of luminescence property of defects in ZnO.This thesis mainly contains two part of work.We obtain different doping level of F dopped and Na dopped ZnO bulk single crystal using ions implantation method respectively.We mainly explore the role of the impurities in ZnO by photoluminescence(PL),Raman scattering,Secondary ion mass spectrometry(SMIS)and electron paramagnetic resonance(EPR).The main results could be summarized as follows:1.F+ion-implanted c-plane(0001)ZnO single crystal was prepared under different implantation dose and annealing temperature.Raman scattering shows damage can be effectively removed with annealing.F atoms are in the substitution position of O atoms in ZnO single crystal,playing the role of shallow donors.PL shows When Annealing temperature exceeds 600 ? or more,F atoms outdiffuse as the annealing time prolonged.That makes DAP emission move toward Vo related defects emission.When the annealing temperature is lower than 600 ?,F atoms stay in ZnO single crystal as the annealing time prolonged thus having no effect on the luminous behavior of DAP emission.What's more,we found that the energy of F neutral bound exciton(D0X)emission is about 3.364 eV.When annealing temperature is lower,the value of D0X is lower than 3.364 eV because of F outdiffusion at high temperature.When the dose increases,no matter the annealing temperature,F atoms concentration is too high to cause reduction of D0X emission peak value.2.Na+ ion-implanted a-plane(1120)ZnO single crystal was prepared under different implantation dose and annealing temperature.Raman scattering shows annealing can remove crystal damage.Low temperature PL was used to evaluate the acceptor evolution with annealing temperature and in Na-implanted a-plane bulk ZnO.After 650? annealing,the crystals implanted with 1014-1016 cm-2 dose of Na show acceptor bound exciton PL around 3.35 eV,suggesting the formation of Na acceptor.The acceptor level is determined to be 171 meV.