Ying-Ge Yang

Thickness dependence of structural, optical and electrical properties of ZnO:Al films prepared on flexible substrates

The thickness dependence of structural, optical and electrical properties of the ZnO:Al films on polypropylene adipate (PPA) substrates have been studied. It was observed that with an increase in film thickness, the crystallite sizes and the density of the films were increased, the resistivity was decreased, and the average transmittance in the wavelength range of the visible spectrum was also slightly decreased.

Bias voltage dependence of properties for ZnO:Al films deposited on flexible substrate

Abstract Highly transparent conducting Al-doped zinc oxide (ZnO:Al) films with good adherence were deposited on water-cooled polypropylene adipate (PPA) substrate using bias r.f. magnetron sputtering. Films with resistivities as low as 4.6×10 −4 Ω cm and transmittance over 80% have been obtained by adjusting the negative bias voltage of the substrate. The dependence of the structural, electrical and optical properties of these films on the substrate bias voltage was studied in detail.

Comparison of the properties for ZnO:Al films deposited on polyimide and glass substrates

Transparent conducting aluminum–doped zinc oxide (ZnO:Al) films have been prepared on polyimide (PI) and Corning 7059 substrates by r.f. magnetron sputtering technique at low substrate temperature (25–210 °C). Polycrystalline ZnO:Al films having a preferred orientation with the c-axis perpendicular to the substrate were deposited with resistivity as low as 8.5 × 10 −4 cm on PI substrates and 7.1 ×10 − 4 cm on glass substrates. The average transmittance exceeded 74 and 85% in the visible spectrum for 360 and 390 nm thick films deposited on PI and glass, respectively. A comparison of the properties of the films deposited on glass and organic substrates was performed.

Preparation and properties of GaN nanostructures by post-nitridation technique

Abstract Nanostructure GaN films were prepared by post-nitridation technique. The morphology and structure of GaN nanowires are investigated by using transmission electron microscopy and scanning electron microscopy. The growth mechanism of the GaN nanowires is unlikely to be controlled by the well-known vapor–liquid–solid mechanism, vapor–solid phase was involved in the growth of GaN nanostructures. A strong blue photoluminescence is observed for room temperature measurement.

Structure and luminescence of GaN films by sputtering post-annealing-reaction technique

Abstract Gallium nitride (GaN) films were prepared on quartz substrates by sputtering post-annealing-reaction technique. The sputtered Ga 2 O 3 films were used as a precursor for GaN growth. X-ray diffractometer, X-ray photoelectron spectroscopy and TEM measurement results indicate that the obtained GaN films are polycrystalline films with hexagonal structure, which consist of single-crystalline nanorods. A strong blue photoluminescence located at 458 nm and a UV photoluminescence located at 370 nm is observed at room temperature.

Investigation of preparation and characterization of GaN films on sapphire (0001) substrates

Gallium nitride (GaN) films were prepared on sapphire (0001) substrates by post-nitridation technique. XRD, XPS, and TEM measurement results indicate that the polycrystalline GaN with hexagonal wurtzite structure was successfully grown. Intense room-temperature photoluminescence peaked at 466 nm of the films is observed.

Properties for GaN films on silicon (111) substrates

High-quality gallium nitride (GaN) films were prepared on Si substrates by sputtering post-annealing-reaction technique. XRD, XPS, and SAED reveal that the films consists of hexagonal wurtzite GaN wiht c-axis oriented polycrystalline grains. A strong UV photoluminescence located at 354 nm is observed for room temperature measurement. The bandgap of these films has a blueshift wiht respect to bulk GaN.

Structural properties of SnO2:Sb transparent conducting films deposited on flexible substrates

Antimony doped tin oxide films have been deposited on flexible substrates such as polyimide and polypropylene adipate. And the structural properties of the films have been investigated. The XRD measurements reveal that all of the obtained films were polycrystalline with the rutile structure. With increasing the substrate temperature and film thickness, the crystallinity of the resulting films is improved and the crystalline size becomes larger. The substrate temperature and film thickness dependence of crystallinity for the SnO2:Sb films were further revealed by their atomic force micrographs, which is consistent with the XRD observations. The XPS details of the SnO2:Sb films are also given. The tin core levels Sn 3d5/2 are observed at 486.5 and 494.9 eV, respectively, while the O 1s peak is obtained at 530.6 eV. It can be seen that the oxygen peak in the spectra is asymmetric, which is due to the concealed Sb 3d peak. The gap between the Sn 3d5/2 and Sn 3d3/2 levels is approximately the same as in the standard spectrum of Sn.