| ZnO film is a novel II - IV direct oxidic semiconductor with wide band gap energy of 3.3eV and exciton binding energy of 60meV at room temperature. Due to its the prerequisite for visible or ultraviolet light emission at room temperature, it has thetremendous potential applications for ultraviolet detectors, LEDs, LDs. ZnO thin film is used widely and effectively in the fields of surface acoustic wave devices, solar cell, gas sensors, varistors and so on because of its excellent piezoelectrical, transparent and conductive performance.In this paper, the Al3+-doped ZnO thin films were deposited on glass substrate (microscope slides) by Sol-Gel process from 2-methoxyethanol solution prepared by Zinc acetate as precursor,monoethanolamine as stabilizator and aluminum nitrate reaction. Homogenous, transparent, polycrystalline ZnO thin film was formed finally by dipping coating,film-plate on substrate conducted by drying, pre-heat-treatment and anealing.By the measurements of SEM, XRD, four-probe method and UV-Vis spectroscopy, the thin film was analysed. The result proved that the thin film with strongly preferred orientation of C-axis prependicular to the substrate surface;which surface was homogenous, dense and crackfree was the crystalline phase of hexagonal wurtzite. The thin film was composed of plentiful asteroidal crystal which crystal dimension approximate to 70100nm. The average transmittance of thin film in visible region was above 80%. The results of measurements else also proved that the thickness of 10 coatings was 1μm, this films resistivity was found to be 5×10-2Ω·cm.The resistivity of thin film influenced by dope-content, preheat treatment, anealing were reseached respectively.Chemical mechnism of ZnO thin film prepared by Sol-Gel technique wasdiscussed by DTA . And also try to discuss the conducting mechanism involving carrier concentration, mobility, scattering , energy band structure, grain boundary and defect.
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