Al掺杂对ZnO薄膜形貌和光学性能的影响

Effect of Al Doping on Morphology and Optical Properties of ZnO Films

摘要:

采用溶胶-凝胶旋涂法在FTO玻璃衬底上制备得到了不同Al掺杂浓度的ZnO薄膜(AZO)。利用XRD、FESEM、UV-vis和PL等测试手段对样品结构、形貌和光学性能进行了表征。结果表明,合成的AZO薄膜均为六方纤锌矿结构且峰强随掺杂浓度的升高而减弱；同时,颗粒形貌由不规则向规则球形转变且尺寸逐渐减小；PL谱中的近紫外发射峰和晶格缺陷峰值随掺杂浓度的升高先增大后降低；由UV-vis吸收光谱可知,AZO薄膜在设定波长内的光吸收处于波动状态,且当Al掺杂浓度为3%时,光吸收强度最高,禁带宽度减小到3.12eV。

Abstract:

Al-doped ZnO (AZO) thin films were prepared on FTO glass by sol-gel method. The phase, morphology and optical properties of the samples were characterized by XRD, FESEM, UV-vis and PL spectroscopy. The results indicate that all the AZO thin films were hexagonal wurtzite structure, and the peak of which decreases with the increase of doping concentration. The morphology of particles transforms from irregular to regular sphere with a decreasing size. The corresponding PL spectra show that the near ultraviolet emission and defect peak increase firstly and then decrease with the increase of doping concentration. The UV-vis absorption spectrum shows that the optical absorption of the AZO thin films is in a fluctuating state. The band-gap of the samples doped with 3% Al reduces to 3.12eV.