An attempt to prepare ZnO-based thin films for varistor was made by metallic alkoxide method. Zn(CH{sub}3COO){sub}2, Bi(OCH{sub}3){sub}3, CoCl{sub}2 and MnCl{sub}2 were the starting materials. Each additive was 1 mol.% to Zn. An appropriate concentration of 2,2'-iminodiethanol was added to a 2-propanol suspension of the starting materials to give a clear solution. The homogeneous films preferentially oriented to the c-axis could be dip coated on the SiO{sub}2 glass substrate. By dip coating into the Zn, Co and Mn mixed solution for the first 20 times and then into the Bi solution for 2 times, the crystallinity of the films was improved. The composition of this film was confirmed using the ICPS method. Nonlinear current-voltage characteristics have been observed on the films sintered at 1073 K for 48 hrs. Long annealing time for the grain growth of ZnO is considered to be important for the nonlinear current-voltage characteristics.
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