Transparent ZnO films were fabricated on glass substrates by a chemical bath deposition method using zinc acetate solutions also containing AlCl3. A predominant effect of the Al3+ addition seemed to be suppression of the growth of ZnO crystals and change of the crystallographic orientation of ZnO films. The c-axis and the a-axis of the ZnO films came to stand parallel and vertical to the substrate, respectively, by increasing the Al3+ concentration. A post ultraviolet irradiation to the films led to a decrease in the sheet resistance from the order of 106 to 104 Ω·sq.-1 without changing the morphology or the crystallinity. This might be related to the photocatalytic effect of ZnO to decompose residual organics in the films and increase the number of carriers. The ZnO film obtained from the solution with 1.0 mol % AlCl3 showed the lowest sheet resistance of 2.5 × 104 Ω·sq.-1.
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