溶胶凝胶工艺制备NaMgZnO复合薄膜结构和发光性能研究

The structure and luminescence properties of NaMgZnO composite thin films prepared by sol-gel method

利用溶胶-凝胶旋涂工艺在玻璃基底上生长NaxMg0.2Zn0.8-xO(x=0.02、0.04、0.06)复合薄膜和本征ZnO薄膜.使用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、紫外-可见分光光度计(UV-Vis)和光致发光系统(PL)分别对薄膜的晶体结构、表面形貌、光学透过率和光致发光性能进行表征.结果表明:引入Na元素和Mg元素可有效提高薄膜的结晶质量,随着Na掺杂量的增加,薄膜的晶粒尺寸逐渐增大,x=0.06时,薄膜平均晶粒尺寸相对最大,达到43.9nm.由扫描电镜结果可知,x=0.02时薄膜晶粒较为致密,而当x=0.06时,出现若干较大白色晶粒,可能是过量的Na元素以NaCl的形式析出所致.PL谱分析可知,样品主要有2个发射峰,一个是位于370nm左右强度较大的紫外发射峰;另一个是500nm附近的绿光峰.而组分为Na0.02Mg0.2Zn0.78O复合薄膜的光致发光谱仅有一个强度较大的紫外发光峰,并且其强度远高于其他样品,说明此时薄膜的紫外发光性能得到了明显的提高.

The sol-gel spinning process was used to grow NaxMg0.2Zn0.8-xO(x=0.02,0.04,0.06) composite films and intrinsic ZnO films on common glass substrates.X-ray diffraction (XRD),scanning electron microscope (SEM),ultraviolet-visible spectrophotometer (UV-Vis) and photoluminescence (PL) were used to analyze and study the structure,lattice parameters,crystal quality,surface morphology,optical transmittance and photoluminescence of the films.The results show that the addition of Na element and Mg element of ZnO thin films can effectively improve the crystal quality of the films.With the increase of Na + doping amount,the grain size of the film increases gradually.When x =0.06,the average grain size of the film is the largest,reaching 43.9 nm.The scanning electron microscopy shows that the film grains are denser when x =0.02,and when x =0.06 the films appear large white grains,which may be caused by excessive Na element precipitation in the form of NaCl.According to the PL spectrum analysis,the samples mainly have two emission peaks,one is the ultraviolet emission peak with a strong intensity at around 370 nm,and the other is the green light emission peak near 500 nm.The PL spectrum of the composition of Na 0.02 Mg 0.2 Zn 0.78 O composite film has only ultraviolet emission peak with higher intensity.Compared with other films,the intensity of the ultraviolet emission peak is enhanced by about 2~8 times,and the ultraviolet luminescence of the film performance has been significantly improved.