• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.806-807
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• 2006

• Journal of the Korean Vacuum Society
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• v.7 no.s1
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• pp.85-99
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• 1998

A ultrahigh vacuum chemical vapor deposition(UHVCVD)/metalorganic chemical vapor deposition(MOMBE) system equipped with a radio frequency(RF)-plasma cell was employed to grow GaN layer on the sapphire at a low temperature. The x-ray photoelectron spectroscopy analysis of nitrogen composition on the nitridated sapphite surface indicated that a nitridation process is mostly affected by the RF power at low temperature. Atomic force microscope images of nitridated surface the protrusion density on the nitridated sapphire is dependent on the nitridation temperature. The crystallinity of GaN grown at $450^{\circ}C$ was found to be much improved when the sapphire was nitridated at low temperature prior to the GaN layer growth. Moreover, a strong photoluminescence spectrum of GaN grown by UHVCVD/MOMBE with a rf-nitrogen plasma was observed for the first time at room temperature.

• Advances in materials Research
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• v.1 no.1
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• pp.75-81
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• 2012

In this work, the Co-doped ZnO rods were prepared by the hydrothermal method. The size of these rods can be changed from micro-size to nano-size by using different solutions during the preparation. The results of transmission electron microscopy (TEM) and selected area electron diffraction (SAED) showed that the as-prepared nano-sized Co-doped rods have single-crystal structure. The polarized Raman experiments were presented on an individual micro-sized Co-doped ZnO rod in the $X(YY)\vec{X}$, $X(ZY)\vec{X}$ and $X(ZZ)\vec{X}$ configurations, the results of polarized Raman indicated that these rods are crystallized and their growth direction is parallel to c-axis.

• Proceedings of the Korean Vacuum Society Conference
• /
• 1997.07a
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• pp.56-57
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• 1997

• Polymer Science and Technology
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• v.26 no.4
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• pp.305-312
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• 2015

• Proceedings of the Korean Vacuum Society Conference
• /
• 2003.08a
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• pp.68-68
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• 2003

• Proceedings of the Korean Powder Metallurgy Institute Conference
• /
• 2004.11a
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• pp.71-72
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• 2004

• 한국전자현미경학회:학술대회논문집
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• 2002.05a
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• pp.54-56
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• 2002

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1671-1672
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• 2007

• Proceedings of the Korean Powder Metallurgy Institute Conference
• /
• 2006.09b
• /
• pp.896-897
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• 2006

In the viewpoint of engineering, materials problem is a key problem, which determines whether the exploitation of fusion energy will be success. The most important class of fusion materials is plasma-facing materials (PFM). W, as high Z high melting-point metal is one of the most important candidate materials due to its high plasma erosion resistance. Improving the ductility of W and W based alloy, lowering its ductile-brittleness transition temperature for meeting the requirements of fusion application is an important task. In this paper, severalpowder meatllurgy methods of fabricating W and W based materials are being investigated.