碩士
國立清華大學
物理學系
93
In order to classify the superconducting phase within Ba2YRu1-xCuxO6 (BaY2116) system, both BaY2116 crystals and bulks have been prepared and investigated. Crystals were grown in a ...homemade furnace with PbO+PbF2 flux, that is a high temperature solution growth technique, and bulks were prepared by a typical solid state reaction Crystals were grown from 1120℃ to 1100℃ by a cooling rate 0.2℃~0.5℃ per hour, where bulks were sintered in air at 1460℃~1485℃ for 2 hours. XRD, SQUID, SEM/EDS and EPMA were performed on these two kinds of samples. Bulks were further examined by R-T and TEM to obtain more information about electrical properties and nanostructure.
The EDS mapping of the crystal surface showed that Cu and Ru can not coexist in the same region, and it also contained PbO precipitation. Some region only had Y, Ba, Cu, and O. Inside the crystal, the Ba3YRu2O9 was surrounded by Ba2YRuO6 and accompanied with Pt and Cu precipitations. The diamagnetic signal was eliminated after polishing the su
碩士
國立中央大學
化學工程與材料工程研究所
99
Eutectic alunimun/amorphous-germanium (Al/a-Ge) bilayer thin film is characterized by its remarkable hermetic sealing in wafer-level bonding in microelectromechanical ...system (MEMS) devices. This study investigates metal-induced crystallization (MIC) of the amorphous Ge and the layer exchange of Al and Ge. The a-Ge(100 nm)/Al(100 nm) bilayer thin films were deposited by sputtering technique and separately sealed in glass tubes in a vacuum of 10^-3 Torr. The samples were analyzed mainly by scanning electron microscopy (SEM), energy dispersive Spectrometer (EDS) analysis, and x-ray photoelectron spectroscopy (XPS). From the results we found that the diffusion behavior was impervious to the time evolution at room temperature. a-Ge began induced crystallization by Al when annealing at 200°C. Layer exchange of Al and Ge occurred at 300°C of annealing for 10 days. A kinetic mechanism is developed to explain the layer exchange phenomenon of Al and Ge system. Extrusions were found on the su
