Al、N掺杂ZnO薄膜的制备及其ZnO第一性原理计算

发布时间：2018-02-26 07:28

  本文关键词： AACVD Al、N掺杂ZnO 双源 雾化间隔 第一性原理计算　出处：《燕山大学》2015年硕士论文　论文类型：学位论文

【摘要】：氧化锌透明导电薄膜由于在光学器件、透明导电电极以及太阳能电池薄膜潜在的应用而越来越引起重视。本文通过气溶胶辅助化学气相沉积法(AACVD)制备Al、N掺杂ZnO薄膜并通过第一性原理计算给以理论上指导。通过X射线衍射仪(XRD)、紫外-可见分光光度计(UV-Vis Spectrophotometer)、荧光光谱仪、四探针、原子力显微镜(AFM)以及扫描电子显微镜(SEM)分别对ZnO薄膜结构、光电学性能以及表面形貌进行表征。分析结果表明通过AACVD法制备的薄膜都为具有高纯度的六方纤锌矿结构的ZnO。前驱液体积对AZO薄膜晶体取向和结晶度没有太大影响,但会明显影响到薄膜的光电学性能以及薄膜的形貌,其中前驱液为35 ml时薄膜具有最佳的性能,方阻仅为1.63 K?/□,透过率为88.53%。通过双源法可以将不同前驱液制备的薄膜各种优良性能结合到一起,即制备具有较高透过率又具有低电阻的高质量AZO薄膜。当乙醇为15 ml和甲醇为20 ml时AZO薄膜具有最佳的光电学性能,质量因子为5.64×10-4。薄膜的表面形貌也严重依赖前驱液中乙醇和甲醇的比例。采用间歇式雾化会提高薄膜的各方面性能,通过对雾化间隔以及雾化时间对薄膜性能的影响的研究当雾化时间一定时,雾化间隔4 min所制备的薄膜具有最佳的性能,当雾化间隔恒定时,雾化时间为8 min时AZO性能最好。N掺杂ZnO薄膜时,Zn和N最佳比例为1:0.5,通过Al-N共掺与单掺ZnO薄膜的比较,共掺ZnO薄膜的性能要优于单掺时ZnO薄膜的性能。温度对Al-N薄膜性能的影响非常明显,尤其在光学性能和形貌上。当温度为350℃时薄膜透过率仅为65.7%,制备Al-N共掺薄膜最佳的衬底温度为400℃。通过第一性原理计算,N原子替代O原子和Al-N共掺时,ZnO呈现p型导电,但当N替代Zn位时薄膜为n型导电。不同掺杂ZnO所需要的形成能也不同,Al掺杂和Al-N共掺所需要的形成能低,而N替代O位时所需要的形成能要低于N替代Zn位时所需要的形成能。缺陷会明显影响Al-N共掺ZnO的电子结构和光学性能,当ZnO中存在Oi缺陷时所需要的形成能最低。
[Abstract]:Zinc oxide transparent conductive thin films due to optical devices, The potential applications of transparent conductive electrodes and solar cell thin films have attracted more and more attention. In this paper, AlN doped ZnO thin films were prepared by aerosol assisted chemical vapor deposition (ACVD) and theoretically indicated by first principles calculation. Through X-ray diffractometer, UV-Vis Spectrophotometerium, fluorescence Spectrometer, UV-Vis Spectrophotometer, UV-Vis Spectrophotometer, fluorescence Spectrometer, UV-Vis Spectrophotometer, fluorescence Spectrometer, UV-Vis Spectrophotometer, fluorescence Spectrometer, Four probes, atomic force microscopy (AFM) and scanning electron microscopy (SEM) were used to study the structure of ZnO films. The results showed that the films prepared by AACVD method were all hexagonal wurtzite structures with high purity. The volume of precursor solution had no great effect on the orientation and crystallinity of AZO thin films. However, the optoelectronic properties and the morphology of the films are obviously affected. The film has the best performance when the precursor solution is 35 ml, and the square resistance is only 1.63 K? R -, the transmittance is 88.53. Through the dual source method, we can combine all kinds of excellent properties of the films prepared by different precursors. High quality AZO thin films with high transmittance and low resistance were prepared. When ethanol was 15 ml and methanol was 20 ml, AZO thin films had the best optoelectronic properties. The quality factor is 5.64 脳 10 ~ (-4). The surface morphology of the film also depends heavily on the ratio of ethanol to methanol in the precursor solution. The effects of atomization interval and atomization time on the properties of the film were studied. When the atomization time was constant, the film prepared by the atomization interval of 4 min had the best performance, when the atomization interval was constant, When the atomization time is 8 min, the best ratio of Zn and N is 1: 0.5 when AZO is doped with ZnO. The comparison between Al-N co-doped and single-doped ZnO films is carried out. The properties of co-doped ZnO films are better than that of single-doped ZnO films, and the effect of temperature on the properties of Al-N films is very obvious. Especially in terms of optical properties and morphology, when the temperature is 350 鈩，

本文编号：1537060