Spray pyrolysis of ZnO–TFTs utilizing a perfume atomizer

• Homogeneous deposition of ZnO layers utilizing a perfume atomizer.
• The Homogeneity is correlated to the droplet size distribution in the aerosol.
• Fabrication of ZnO–TFTs from non-toxic solvent by perfume atomizer is reported.
• High mobility of 5 cm2 V−1 s−1 and perfect on-set of 0 V are obtained for the TFTs.
• TFT performance is correlated with growth rate attributed to impurity level change.

Successful deposition of ZnO layers from non-toxic solvent by utilizing a perfume atomizer is demonstrated. The adsorption edge of the zinc oxide films was found to be 3.22 eV which is in good agreement with literature. In addition it is found that the homogeneity of the films increases in side geometry with increasing distance to the perfume atomizer due to the droplet size distribution along the x-axis of the aerosol. The films were used to fabricate ZnO–TFTs. A dominating influence of the grain sizes can be excluded by correlating atomic force microscopy (AFM) images to the electrical properties of the transistors deposited in different geometries but a strong influence of the transistor performance on the growth rate was found. The increase in performance with decreasing growth rate was attributed to a longer reaction time decreasing the impurity level in the films. The linear mobility, the on-set voltage and the on–off current ratio are found to be 5 cm2 V−1 s−1, 0 V and 106 for small growth rates, respectively. Hence the transistors show high mobility and an excellent switching behavior.