ZnO缓冲层厚度对Al掺杂ZnO薄膜性能的影响

Effects of ZnO buffer layer thickness on the properties of Al doped ZnO thin films

采用射频磁控溅射法在不同厚度的ZnO缓冲层上制备了Al掺杂ZnO(AZO)薄膜.利用X射线衍射(XRD)、扫描电子显微镜(SEM)、紫外-可见分光光度计(UV-VIS)和荧光分光光度计(PL)等表征技术,研究了AZO薄膜的微观结构、表面形貌和发光特性.XRD分析结果表明,加入适当厚度的ZnO缓冲层后可有效地降低晶格失配和因热膨胀系数不同引起的晶格畸变.薄膜在可见光范围内的透射率随着缓冲层厚度的增加先增大后降低,平均透过率超过80%.通过对样品光致发光(PL)谱的研究发现ZnO缓冲层样品在室温下的光致发光峰有了明显增高.这说明利用低温缓冲层生长的AZO薄膜的结晶质量和光学性质都得到了明显改善.

The Al-doped ZnO（AZO） thin films with different ZnO buffer layer thickness are deposited on ZnO buffer layer by reactive RF magnetron sputtering technology.The microstructure,surface morphology,luminescence properties of the AZO thin films are characterized by X-ray diffraction（XRD）,scanning electron microscopy（SEM）,UV-VIS spectrophotometer and photoluminescence（PL） spectrum,respectively.XRD measurements reveal that ZnO buffer layer at low temperature can reduce the lattice distortion caused by lattice misfit and difference of the thermal expansion coefficients.The transmittance first increase and then decrease with increasing ZnO buffer layer thickness and the AZO films show the average transmittance above 80% in the visible range.The PL spectra peak value of the sample which have ZnO buffer layer increases obviously at room temperature.The crystal quality and optical properties of the AZO thin film are improved significantly.