Al-doped zinc oxide (ZnO:Al) films were applied to liquid crystal displays (LCDs) as transparent electrodes substituting indium tin oxide (ITO). While the ZnO:Al-based twisted nematic LCD cell showed similar operational behavior to ITO-based counterpart, its electro-optical (EO) and residual dc (r-dc) characteristics were somewhat improved. Capacitance-voltage relations suggested that these improved EO and r-dc characteristics of the ZnO:Al-based LCD cell are due to the substantially lower density of charge carrier trapping centers in the polyimide layer∕electrode interface region, demonstrating high application potential of ZnO:Al films as transparent electrodes of LCDs.

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The effects of different annealing atmospheres on the chemical surface structure of HfO2 gate dielectric layers have been evaluated in terms of the improvement in the transconductance (gm), current on/off ratio (Ion/Ioff), and carrier mobility (μe) of a back-gated ZnO nanowire field-effect transistor (FET). Compared to O2 and N2 annealed HfO2-gated transistors, the H2 annealed HfO2-gated ZnO nanowire FET exhibited a higher transconductance of 1.77 × 10−7 A V−1, on/off current ratio of ∼1.2 × 104, and electron mobility of 11.90 cm2 V−1 s−1.

We present the annealing effects on nanochemistry and electrical properties in HfO2 dielectrics grown by metalorganic molecular-beam epitaxy. After the postannealing treatment of HfO2 films in the temperature range of 600–800°C, the thicknesses and chemical states of the films were examined by high-resolution transmission electron microscopy and angle-resolved x-ray photoelectron spectroscopy. By comparing the line shapes of core-level spectra for the samples with different annealing temperatures, the concentrations of SiO and Hf-silicate with high dielectric constant are found to be highest for HfO2 film annealed at 700°C. This result supports that the accumulation capacitance of the sample annealed at 700°C is not deteriorated in spite of a steep increase in interfacial layer thickness compared with that of the sample annealed at 600°C.

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