【作者】 龙涛；

【导师】 朱德贵；

【作者基本信息】 西南交通大学 ， 材料学， 2004， 硕士

【摘要】 本文概概述了透明导电薄膜的性能、制备技术和应用前景。并以ZnSO₄．7H₂O和NH₄Al（SO₄）₂．12H₂O为主要原料，NH₄HCO₃为沉淀剂采用液相共沉淀法制备了Al₂O₃，含量为2.5wt％的ZnO／Al₂O₃，超细复合粉末；分别在不同温度下对复合粉末进行H₂气还原处理：分别以ZnO／Al₂O₃复合粉末、还原ZnO／Al₂O₃复合粉末、纳米ZnO与纳米γ-Al₂O₃的混合粉末为原料采用热等静压（HIP）工艺制备了ZnO／Al₂O₃陶瓷靶材；对ZnO／Al₂O₃陶瓷靶材进行射频磁控溅射和直流磁控溅射制备了铝掺杂氧化锌（ZAO）透明导电薄膜。 采用XRD、SEM和TEM等分析方法，分析了ZnO／Al₂O₃复合粉末及前驱体、ZnO／Al₂O₃陶瓷靶材和ZAO透明导电薄膜的相组成与形貌；用TG／DSC热分析法研究了粉末前驱体的热分解情况；用XPS分析法研究了还原温度对粉末性能的影响；用激光粒度分析技术测定了复合粉末的平均粒度及其分布；用原子吸收谱（AAS）分析了粉末前驱体中各杂质元素的含量：用显微硬度分析法分析了靶材的维氏硬度（H_γ）和断裂韧性(K_IC)；测定并分析了靶材的体电阻率、薄膜的方块电阻及体电阻率和薄膜的可见光透射率： 对复合粉末的分析研究表明：各复合粉末样品均存在不同程度的颗粒“团聚”：前驱体经680℃×12h焙烧后得到的复合粉末性能较好，粉末体积平均粒径为12.250μm；粉末的还原温度超过700℃时，ZnO发生分解。 各靶材样品的XRD、SEM和TEM分析结果表明：以还原和未还原ZAO粉为原料的靶材组织中出现了第二相组织：ZnAl₂O₄，而以纳米ZnO、Al₂O₃粉为原料的靶材组织中未见第二相。靶材的力学性能和导电性分析结果表明：以还原粉为原料的靶材导电性和综合力学性能最佳，且各靶材的致密 西南交通大学硕士研究生学位论文第n页度均在97%以上，断裂韧性接近或超过1.oMPa.m，/，，电阻率均在10一3Q.。。量级，靶材具有良好的机械加工和电火花加工性能。 薄膜的电学性能分析结果表明:ZAO薄膜的电阻率受基片温度（Ts）、溅射功率和溅射气氛中氧浓度的影响较大。TS为330℃时直流磁控溅射法制得的ZAO薄膜的电阻率为9.3 xlo一，Q .Cm，是本文得到的最低薄膜电阻率;采用射频磁控溅射法制备的ZAO薄膜电阻率在TS为330℃时也降至最低为l.4x1o一:，Q.em。 薄膜的透光性分析结果表明:各薄膜样品的可见光透射率平均值均在80%以上;随着基片温度的升高，薄膜透射率升高，且薄膜透射曲线吸收边缘向短波方向移动。更多还原

【Abstract】 In this paper, the properties, preparation methods and applications of transparent conducting thin films were reviewed. ZnO/Al2O3 compound powders with 2.5wt% Al2O3 were synthesized by coprecipitation method using ZnSO4.7H2O and NH4Al(SO4)2 12H2O as the raw materials and NH4HCO3 as the precipitator. Then the compound powders were reduced by H2 gas at different temperatures. Three kinds of ZnO/Al2O3 ceramic targets were fabricated by hot isostatic pressing (HIP) method with three kinds of powders: reduced compound powder, compound powder and nanometer powders. Aluminum-doped zinc oxide (ZAO) transparent conducting thin films were prepared with ZnO/Al2O3 ceramic targets by r.f. or dc magnetron sputtering method.Phase compositions and morphologies of ZnO/Al2O3 compound powders, pioneer-precipitates of the compound powders, ZnO/Al2O3 ceramic targets and ZAO transparent conducting thin films were investigated by XRD, SEM and TEM. Thermochemistry performances of the pioneer-precipitates of the compound powders were investigated by TG/DSC methods. XPS was applied to analyze the influences of reduction process on the properties of powders. The particles size and size distribution of the compound powders were studied by laser technology. Moreover atomic absorption spectroscopy (AAS) method was used to determine the proportion of impurity elements in the pioneer-precipitate of the compound powders. The hardness Hy and fracture toughness KIC of the targets were determined through microhardness analysis. The resistivity of the targets, the sheet resistance and optical transmittance ofZAO films were measured.The investigation for the compound powders and pioneer-precipitates indicates that particle conglomerations exist in all the compound powders. And the particle size of the compound powder is 12.25 \xm in average. The powder baked at 680C is perfect in properties, and zinc oxide will decompose when the reduction temperature exceeds 700 C,Results of XRD, SEM and TEM for the targets indicate that secondary phase ZnAl2O4 exists in the targets synthesized with reduced or unreduced compound powders, but not in the target synthesized with nanometer powders. The analytical results for the mechanical and electrical properties of the targets indicate that the target synthesized with reduced compound powders has the best general properties, furthermore the relative densities and fracture toughness of all the targets exceed 97% and 1.0 MPa.m1/2 respectively, and the resistivity of the targets attains 10-3.cm. These results indicate that ZAO targets synthesized by HIP can be easily machined by electrical and mechanical machining.Investigation for electrical properties of the films indicates that substrate temperature, sputtering power and oxygen fraction have great impacts on the properties of the films. The resistivity of the films prepared by dc magnetron sputtering under the substrate temperature 330C is 9.3x10-4.cm which is the lowest resistivity of the films in this paper. The lowest resistivity of the films prepared by r.f. magnetron sputtering under the substrate temperature 330C is 1.4x10-3.cmStudy for optical transmittance of the films indicates that the average value of the optical transmittance of the films exceeds 80%. With the substratetemperature increasing the average optical transmittance increases and the absorption edge of the transmission curve of the films moves toward short wavelength.更多还原