Growth temperature on ZnO:Al thin films morphology and optical properties

ZnO:Al thin films were deposited on a glass substrate by a sol-gel method with a combined two-step, spin coating and growth treatment in a water bath. The effect of Al incorporation and the bath growth temperature on the crystal structure, morphology and optical properties of the samples are investigated. The results showed that the morphology of 3% Al-doped film was rod-like nanostructure at 40 degrees C and granular at 60 and 90 degrees C. The lattice strain increases after the Al-doping at 40 and 60 degrees C. And the strain of 3% Al-doped film decreased with increasing the bath growth temperature. The optical band gap of pure and 3% Al-doped film at different bath growth temperature is calculated. Relatively better visible light transmittance and photoluminescence (PL) characteristics were obtained at 40 degrees C. Blue emission associated with surface defects was observed.

Automated summary

ZnO:Al thin films were deposited on a glass substrate using a sol-gel method with a two-step, spin coating and growth treatment in a water bath, resulting in different crystal structures and morphologies. Optimal optical properties, including better visible light transmittance and photoluminescence, were observed in the 3% Al-doped film at 40 degrees C, where a blue emission associated with surface defects was also identified.