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A room temperature‐processed ZnO thin film transistors (TFT) with zirconium oxide (ZrO2) are demonstrated as a gate dielectric, fabricated by dc magnetron sputtering. The oxygen flow rate dependence of ZrO2 thin films on the optical, structural, and electrical properties is investigated. Nanocrystalline ZrO2 films with a grain size of 6.2–16.8 nm are obtained at room temperature and grain size is found to be a function of oxygen flow rate during deposition. The electrical characterization of the gate dielectric is carried out using the device structure Al‐ZrO2‐Al. The leakage properties and dielectric constants are computed for the gate dielectric grown at different oxygen flow rates. Further, bottom gate staggered ZnO thin film transistors are fabricated with the configuration glass/Al/ZrO2/ZnO/Al and the devices exhibit a field effect mobility of ≈43 cm2 V−1 s−1, a low operating voltage of 1.5 V and on/off ratio of 103. This work could lead to the possibility of low operating voltage TFTs for the next generation display technologies.

The SILAR deposited CdS films were incorporated with various concentrations of zinc using zinc acetate and zinc chloride precursors. The presence of zinc was found to alter the crystal structure and energy bandgap of the films. The bandgap increased by nearly 44% with the increase of zinc concentration in the films. The photoluminescence spectra of the films revealed the presence of several localized defects levels within the forbidden bandgap. The peak spectral response wavelength was found to vary from 500 nm to 400 nm with the increase of zinc. The photocurrent was found to increase with the Cd:Zn ratio. The films with relatively high concentrations of zinc were found to be better suited for the photodetector applications due to their higher photocurrent to dark current ratio.