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Zinc oxide (ZnO) as a wide gap with the semiconductor material (crystal constant a = 0.3250nm c = 0.5206nm, the band gap of approximately room temperature 3.30Ev exciton binding energy of about 60 meV), has excellent compressive power, photovoltaic, gas sensing, pressure-sensitive and other characteristics, especially the introduction of small amounts of impurities can usually induced obvious changes in electrical and optical properties. To adjust or improve their performance by doping ZnO thin film research hotspot of. Al-doped ZnO (ZAO) is the most widely used. A lot of the ZAO films of technology, including RF sputtering, molecular beam epitaxy, electron beam reactive evaporation deposition, and sol-gel method. Sol - gel method has the advantages of simple process equipment, film uniformity, the stoichiometric ratio is easy to control, easy to doping and reduce costs. In this thesis, the sol - gel dip coating technology, good crystalline quality grown on quartz substrate, the good orientation ZAO film; through multiple sets of orthogonal experimental design, and explore the film preparation process optimization combination , Al 3 doping amount 1at.%, sol concentration of 0.8 mol / L, the coating layer eight-story, 500 ° C reducing atmosphere (N 2 : H get the best quality films 2 = 96:4) annealing, the film resistivity was 1.275 x 10 -3 Ω · cm, and the average light transmittance of the visible region of 84% ZAO Transparent conductive film preparation process; then, in order to further improve the film properties, they were doped with Sn and La elements prepared by the two double-doped transparent conductive film of the novel ZAO (ZAO: La, and ZAO: Sn). Of the structure, morphology and optical properties of the samples were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), four-probe and UV - visible spectrophotometer instrument. The results show that: the film has a strong (002) preferred orientation growth trend, with the ZnO crystal structure of the hexagonal lead-zinc; higher the annealing temperature, the stronger diffraction peak intensity of X-rays (002) crystal face, the more favorable the film grain growth, the grain size of the film is the larger, more complete crystallization; the ZAO film's resistance took the lead with Al 3 doping amount of the increase is reduced, followed by Al 3 rise of the doping amount of increase; the resistivity of the film is reduced with increasing temperature, but the temperature is too high resistivity resistivity on a downward trend, the reducing atmosphere annealing as compared with the air-annealed, the film resistivity was reduced by about three orders of magnitude; Sn and La elements added, help to improve the performance of thin film transmittance.
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