中文摘要：

研究了KrF准分子激光辐照对ZnO薄膜的本征缺陷.紫外（UV）发光以及表面形貌的影响,并对室温下ZnO的UV发射机理进行了详细探讨.结果表明激光辐照打断了薄膜内Zn—O键,氧空位（锌填隙）增多,导致表面电阻率下降,载流子浓度升高,调节激光辐照能量密度,可在较大范围内调控ZnO薄膜中的施主缺陷浓度;同时在激光热效应作用下,薄膜晶粒熔融长大,表面粗糙度大大降低;室温下ZnO薄膜的UV发光包括自由激子复合发光（FX）及其声子伴线（FX-LO）,缺陷浓度决定了FX与FX-LO的相对强度比,进而影响UV发射峰的强度以及位置.因此,激光辐照可以快速、有效地对ZnO薄膜内的缺陷浓度进行调控,从而控制其室温下的UV发射强度,这对于提高ZnO基光电器件的性能具有重要意义.

英文摘要：

The effect of KrF pulsed excimer laser irradiation on intrinsic defects,ultra-violet（UV） emission and surface morphology of ZnO thin films was investigated,and also the origin of room temperature UV emission was discussed in detail.It was found that,the KrF laser can break the Zn—O bonds;therefore,the concentration of VO（or Zni） defects increases,leading to the decrease of resistivity and increase of carrier concentration.By adjusting the laser energy densities,the donor defect concentration can be controlled in a wide range.Simultaneously,under the heat of laser,the melting grains connect with each other,resulting in the great decrease of surface roughness.Room temperature UV emission of ZnO film is composed of contribution from free-exciton（FX） recombination and its longitudinal-optical phonon replica（FX-LO）,the defect density determines the relative strengths of FX to FX-LO emission intensities,which strongly affect the peak position and intensity of UV emission of ZnO film.This investigation indicates that the laser irradiation is an effective technique to modulate the exciton emission by controlling the defect density,which is important for the application of high performance of UV emitting optoelectronic devices.