Abstract
Transparent and conducting Al-doped ZnO thin films with c-axis-preferred orientation were prepared on glass substrate via sol-gel route. The physical and chemical changes during thermal treatment were analyzed by TG-DSC spectra and the crystallization quality was characterized by XRD patterns. The optimized preheating and post-heating temperatures were determined at ∼420°C and ∼530°C, respectively. From thermodynamic and kinetics views, we investigated the mechanism of orientation growth with (002) plane parallel to the substrates. The surface morphologies of the films, post-heated at 420°C, 450°C, 530°C and 550°C, respectively, were observed by SEM micrographs. The film post-heated at 530°C shows a homogenous dense microstructure and exhibits the minimum sheet resistance of 140 Ω/Sq. The visible optical transmittance of all the films is beyond 90%. In addition, the annealing treatment in vacuum can contribute greatly to the electrical conductivity.
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Chen, J., Chen, D. & Chen, Z. Optimization of the process for preparing Al-doped ZnO thin films by sol-gel method. Sci. China Ser. E-Technol. Sci. 52, 88–94 (2009). https://doi.org/10.1007/s11431-009-0002-y
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DOI: https://doi.org/10.1007/s11431-009-0002-y