Correlation between optical properties and microstructure of undoped Zno thin films grown by PLD

PLD 법으로 성장한 undoped ZnO 박막의 광학적 특성과 미세구조 상관관계

We described the growth of undoped ZnO thin films and their optical properties changing with a various growth temperature. The un doped ZnO thin films were grown on c-$Al_2O_3$ substrates using pulsed laser deposition (PLD) at room temperature, 200, 400, and $600^{\circ}C$, respectively. Field emission microscopy (FE-SEM) measurements showed that the grain size of undoped ZnO thin films are increasing as a increase of growth temperature. In addition, we were investigated that the structural and optical properties of undoped ZnO thin films by x-ray diffraction (XRD) and photoluminescence (PL) studied. Also, we could confirmed that the exciton luminescence was strongly related to charge trap by grain boundary of the samples using micro-PL measurement.