衬底温度对PLD方法制备的ZnO薄膜的光学和电学特性的影响

Effect of Substrate Temperature on the Optical and Electronic Properties of ZnO Film Prepared by PLD

利用脉冲激光沉积法(PLD)在c面蓝宝石衬底上制备了ZnO薄膜并对其进行了X射线衍射(XRD)、反射式高能电子衍射(RHEED)、光致发光(PL)谱和霍尔(Hall)测试。RHEED和XRD分析表明,温度在350℃至550℃之间时,ZnO薄膜的结晶质量随着衬底温度的升高而提高,当衬底温度进一步升高后,ZnO薄膜的结晶质量开始下降。四个样品中,衬底温度为550℃的样品具有最清晰的规则点状RHEED图像和半高宽最窄的(0002)衍射峰。PL谱和Hall测量的结果表明,衬底温度为550℃的样品还具有最好的发光性质和最大的霍尔迁移率。

ZnO thin films were prepared on c-plane sapphire substrates by pulsed laser deposition （PLD）, and their optical and electronic properties were characterized using the measurements of XRD, RHEED, PL spectra and Hall effect. The results of RHEED and XRD indicate that the crystal quality of the ZnO thin film escalated with the increase of substrate temperature from 350℃ to 550℃. When the substrate temperature further increased, the crystal quality of the thin film deteriorated. Among the four samples, the one prepared at 550℃ exhibited the clearest regular spotty RHEED image and the narrowest FWHM of （0002） peak. The results of PL spectra and Hall measurement indicate that samples prepared at 550℃ exhibit good optical property and the highest Hall mobility.