A novel solution-processed amorphous high-k dielectric for thin film transistors (TFTs) has been systemically studied with the objective of achieving high performance and reducing costs for the next generation displays. In this research, the amorphous hafnium silicon multiple oxide (HfSiOx) was fabricated by the simple spin-coating method. Here, we have demonstrated that the incorporation of a silicon oxide has significant effects on the properties of HfO2. The HfSiOx dielectrics have no obvious crystallization peaks even the annealing temperature reach up to 800 o C while the HfO2 films were crystallized at 400 o C. The HfSiOx films have an energy band gap of 6.05 eV, which was wider than HfO2 films (5.69 eV), the breakdown voltage was increased from 2.4 MV/cm (HfO2) to 2.9 MV/cm (HfSiOx) and the leakage current was decreased from 4.4×10 -7 A/cm 2 to 3.7×10 -7 A/cm 2 at an electric field of 2 MV/cm. To achieve optimized device performance, the influence of annealing temperature on the characteristics (including the surface and interface, the chemical and structural evolution) of the solution processed HfSiOx dielectrics was emphasized in this research. To demonstrate the HfSiOx application on oxide TFTs, we fabricated HfInZnO (HIZO) and ZnSnO (ZTO) TFTs with HfSiOx dielectrics, and both of them showed low off-state current indicating the HfSiOx is an attractive candidate used in TFTs. The ZTO TFTs with amorphous HfSiOx dielectrics were operated well under a gate voltage of -0.53 V, exhibiting a high saturation mobility of 153 cm 2 /V·s, a small subthreshold swing of 0.17 V/dec, a large on-off current ratio 3.4×10 7 .

The effects of nitrogen content on the microstructure and the mechanical properties of a cast nickel-base superalloy (CNS) have been investigated experimentally. Experimental results demonstrated that the grain structure of CNS samples was refined by increasing the nitrogen content, but the area percentage of microporosity has been augmented with increased nitrogen content. Increasing the nitrogen content resulted in the morphology evolution of carbide from an acicular or 'Chinese hieroglyphs' type to blocky one, while negligible change of the morphology of γ ′ precipitates was observed. Finally, it was found that the tensile strength has no obvious variation as the nitrogen content increases from 5 to 26 ppm, but it reduces sharply when the nitrogen content is raised to 34 ppm. The elongation decreases gradually with increasing nitrogen content.

X-ray photoelectron spectroscopy (XPS) was utilized to measure the valence band offset (ΔEV) of the TiZnSnO (TZTO)/Si heterojunction. TZTO films were deposited on Si (100) substrates using magnetron sputtering at room temperature. By using the Zn 2p3/2 and Sn 3d5/2 energy levels as references, the value of ΔEV was calculated to be 2.69 ± 0.1 eV. Combining with the experimental optical energy band gap of 3.98 eV for TZTO extracted from the UV-vis transmittance spectrum, the conduction band offset (ΔEC) was deduced to be 0.17 ± 0.1 eV at the interface. Hence, the energy band alignment of the heterojunction was determined accurately, showing a type-I form. This will be beneficial for the design and application of TZTO/Si hybrid devices.

The structural, morphological and optical properties of zinc oxide (ZnO) thin films were investigated. The ZnO thin films were deposited on glass substrate at room temperature (RT) through radio frequency magnetron sputtering in different O 2 flux (fixed Ar flux). The structural properties and morphology were studied by X-ray diffraction and atomic force microscopy, respectively. The highly crystallized ZnO thin films were obtained. It is found that all the films have preferential orientation in c-axis direction and the crystallinity of the films is strongly affected by O 2 flux. The crystallinity is improved greatly when the film is annealed in O 2 ambient. Atomic force microscopy results show that the films are compact and smooth. Near band edge emission peak in photoluminescence spectrum for the typical sample appears red-shift phenomena. All the films present a high transmittance of above 90% in the visible region.