Abstract Multilayer TaC coatings with layers of different porosities, that provide corrosion resistance and controlled wettability against molten metal are prepared via a wet powder process and a subsequent sintering process. A porous TaC top layer with a dense TaC underlayer formed on a graphite substrate is applied as a reactor component. It is found that this layer significantly increases the surface area of a molten Ga source via capillary action due to its high open porosity. It is also demonstrated that this layer enhances the Ga vapor supply rate, and thus the growth rate, during halogen-free vapor-phase epitaxial growth of GaN crystals.

中文翻译：

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GaN晶体生长系统多功能反应器组件湿粉工艺制备的多孔可控多层TaC涂层

摘要 通过湿粉工艺和随后的烧结工艺制备了具有不同孔隙率层的多层 TaC 涂层，该涂层具有抗腐蚀性和对熔融金属的可控润湿性。在石墨基板上形成具有致密 TaC 底层的多孔 TaC 顶层用作反应器组件。发现该层由于其高开孔率而通过毛细作用显着增加了熔融Ga源的表面积。还表明，在 GaN 晶体的无卤气相外延生长过程中，该层提高了 Ga 蒸气供应速率，从而提高了生长速率。