【作者】 谢岩；

【导师】 周建；

【作者基本信息】 武汉理工大学 ， 材料学， 2010， 硕士

【摘要】 铝掺杂氧化锌(AZO)薄膜,一种新兴的宽禁带半导体材料,其透明导电性可广泛应用于制备透明电极和太阳能电池的透明窗口材料,其紫外发光性能可应用于紫外探测器和激光器。AZO薄膜的制备方法主要有磁控溅射,化学气相沉积以及溶胶-凝胶等方法。制备具有可重复性和稳定性的大面积均匀透明导电氧化锌薄膜是目前研究的热点,本论文以溶胶-凝胶法为制备方法,制备了具有高透光率,较低电阻率和一定光致发光性能的AZO薄膜。本论文以二水合乙酸锌作为锌源,六水氯化铝作为铝源,乙二醇甲醚作为有机溶剂,单乙醇胺作为稳定剂,按照一定比例混合,配置成溶胶,并通过旋涂镀膜和退火热处理的方法制备了具有一定光学性能和电学性能的AZO薄膜,讨论了不同衬底,不同退火温度、不同掺杂量、梯度掺杂、缓冲层对AZO薄膜结构形貌、光学性能和电学性能的影响。实验结果表明,硅衬底比玻璃衬底更利于制备具有c轴择优取向的高质量AZO薄膜,且硅衬底上制备的AZO薄膜具有更低的电阻率。硅衬底上铝掺杂量为1.0at%,退火温度为600℃,退火时间为180min时,可以获得具有优异光学性能和电学性能的AZO薄膜,该薄膜的最低电阻率可达4.64×10-3Ω·cm,其尖锐的本征发光峰和近紫外发光峰也表明该薄膜具有较完整的晶体结构；AZO薄膜的透光率受退火温度和掺杂浓度的影响不大,主要受薄膜厚度影响。随铝掺入量的增加,AZO薄膜的表面平整度下降,电导率下降,本征发光峰强度降低,可见光区发光峰强度明显升高；但梯度掺杂的AZO薄膜表面平整度和均匀度有明显提高,而且可以在较大的退火温度区间内获得较稳定的低电阻率,以及较强的本征发光峰；MgO缓冲层的加入使的具有优异光学性能和电学性能的AZO薄膜更容易制备,明显提高了薄膜的质量,而且提高了所制备薄膜的稳定性。室温下ZnO的禁带宽度为3.2eV,铝的掺杂明显提高了ZnO薄膜的禁带宽度,AZO薄膜的禁带宽度随退火温度的升高逐渐降低,随铝掺杂浓度的增加而逐渐升高。更多还原

【Abstract】 Al-doped ZnO (AZO) thin film is a new kind of wide band gap semiconductor material, which can be widely used in preparing transparent electrode and transparent window materials because of its transparent and conductive properties. The UV emission properties can be used in UV detectors and laser. AZO thin films were prepared by magnetron sputtering, chemical vapor deposition, sol-gel method and so on. At present, the most important things for researchers in making the AZO thin film is the stability, reproducibility and uniformity in a large area. In this paper, AZO thin films of high transparency, low resistivity, high photoluminescence properties have been prepared by sol-gel method.In this thesis, the author choose zinc acetate dihydrate as zinc source, aluminum chloride hexahydrate as the aluminum source, ethylene glycol monomethyl ether as an organic solvent, monoethanolamine as stabilizer. The sol was prepared according to a certain ratio, and through spin coating and annealing process, the AZO thin films with excellent optical and electrical properties were prepared. The influence on the morphology, optical properties and electrical properties of AZO thin films were researched, setting the influence factor as different substrates, different annealing temperatures, different intermingled quantity, gradient doping and buffer layer.The experiment results showed that the silicon substrate was more favorable than the glass substrate in preparing oriented along the c-axis plane of AZO thin films and had lower resistivity on silicon substrate. When alumina doping content of 1.0at%, the annealing temperature was 600℃, the annealing time was 180min, the AZO thin film with the most excellence photoluminescence properties and low resistivity can be prepared, the lowest resistivity of the thin film was 4.64×10-3Ω·cm. The sharp intrinsic emission peak and near the UV emission peak indicated that the film had excellent photoluminescence properties. The annealing temperature and doping concentration didn’t affect the transmittance of AZO thin films, which mainly affected by film thickness. With the increase of aluminum doped concentration, the surface roughness of AZO thin films became poor, the electrical conductivity decreased, the intrinsic luminescence peak intensity decreased and the visible emission peak intensity increased significantly. Compared to non-gradient doping, AZO thin films by gradient doped possess more stable and low resistivity in a wider annealing temperature area, as well as higher intrinsic PL peak intensity. MgO buffer layer’s adding made the preparation of AZO thin films with excellent optical and electrical properties more easily and more stable. The band gap of AZO thin films is 3.2eV in room temperature, the aluminum doped increased the band gap of AZO thin films significantly. With the annealing temperature increased, the band gap decreased, with the increase of aluminum doped concentration, the film’s band gap increased gradually.更多还原