Wu Xianying

Preparation and Photocurrent Performance of Highly Ordered Titania Nanotube Implanted with Ag/Cu Metal Ions

Ag/Cu-doped titania nanotubes (Ag/TiNT, Cu/TiNT) are prepared by a metal vapor vacuum arc implanter. A scanning electronic microscope is employed for microstructural characterization. The photo-current performance of doped titania nanotubes under UV and visible light is tested by an electrochemical workstation CS300UA, the results show that the absorption edge of both Ag/TiNT and Cu/TiNT samples shifts to the visible light region and the band gap becomes narrower. Ag/TiNT possesses better photo-current ability than Cu/TiNT under UV and visible light. Titania doped with Ag and Cu metal ions is also studied based on the linearized augmented plane-wave method implemented by WIEN2k package, the result becomes better with the experimental performance.

Silicide synthesis by metal ion implantation and ion deposition

Silicides of cobalt with good properties were prepared using metal vapor vacuum arc (MEVVA) ion implantation. The epitaxial growth of Co silicide was observed by TEM. A continuous silicide layer with thickness of 80-200 nm was obtained. The sheet resistance of Co silicide decreases with increase of ion flux and ion dose. After annealing the sheet resistance decreases further. The phase transition from Co/sub 2/Si to CoSi/sub 2/ was observed when the ion flux and annealing temperature increased. Co (or Mo) silicide is synthesized using Co (or Mo) and Si ion alternant deposition. The coating quality is better than that of Co ion implantation. The power microwave transistors were fabricated using ion implantation, it shows that emitter resistance and noise of the transistor decrease markedly, the microwave property was improved obviously.