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Guoqiang Xie

Publications and source records attributed to Guoqiang Xie.

2 recordsLinked to original sources

Growth of tungsten nanodendrites on SiO2 substrate using electron-beam-induced deposition.

Tungsten nanodendrite structures were fabricated on an insulator SiO2 substrate using an electron-beam-induced deposition process in a high voltage transmission electron microscope. The effect of electron beam accelerating voltage on the nanodendrite structures was investigated. The morphologies and their growth rates did not have obvious difference for the deposition at accelerating voltages from 400 to 1000 kV. A mechanism for the growth and morphology of the nanodendrite structure was proposed involving charge-up produced on the surface of the substrate, movement of charges to and accumulation at the convex surface of the substrate and the tips of the deposits. High-energy electron irradiation enhanced diffusion of W atoms in the nanodendrites, promoted crystallization of W grains, so that more crystallized W nanodendrite structures were achieved by the electron-beam-induced deposition process using higher energy electron beams.

Dendrites↗

Electron microscopy observation of interface in diffusion-bonded copper joint.

The microstructure at the interface of diffusion-bonded joints of oxygen-free high-conductivity copper for two kinds of surface conditions, with and without argon ion bombardment treatment, was investigated using scanning and high-resolution transmission electron microscopy and energy-dispersive X-ray spectroscopy. The results showed that argon ion bombardment effectively removed the surface oxide film layer and lowered the height of the surface asperity, so that inclusion formation was decreased and void shrinkage time was shortened at the interface of the bonded copper joints, and the tensile strength of diffusion-bonded copper joints was improved obviously.

Journal Article↗