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Observation of Diamond Nanoparticles Generated in the Gas Phasse

The generation of nanoparticles in the gas phase during the chemical vapor deposition (CVD) process has been frequently reported with their subsequent deposition into films and nanostructures in many systems such as carbon, silicon and zinc oxide. To confirm the generation of diamond nanoparticles in the gas phase under the synthesis condition of diamond films by hot wire CVD (HWCVD), the transmission electron microscope (TEM) grid membrane was exposed for 1 ~ 10 sec using a capturing system and the grid membrane was observed by TEM. The TEM images showed that the captured diamond nanoparticles had 1 ~ 5 nm of diameter and 2.06 Å of crystalline lattice spacing, which indicates the spacing of {111} plane of diamond. In addition, to investigate the effect of electric bias on the deposition behavior of diamond nanoparticles in gas phase, the electric bias was applied to the holder of the TEM grid. The positive bias increased the number density of diamond nanoparticles whereas the negative bias decreased it, indicating that diamond nanoparticles are negatively charged.


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Observation of Diamond Nanoparticles Generated in the Gas Phasse