Producing silicon carbide based ceramic sintered body that is useful e.g. for fabricating semiconductors, comprises sintering powder body in inert gas atmosphere, and performing gas pressure sintering in nitrogen-containing atmosphere

摘要

The process comprises sintering a powder body in an inert gas atmosphere at a pressure of 1-100 mbar and at a temperature of 2000-2200[deg] C, and performing a gas pressure sintering or a sintering-hot-isostatic press in a nitrogen-containing atmosphere. The powder body: comprises silicon carbide (88 wt.%), a boron-containing additive such as boron carbide in which boron is present in an amount of 0.1-1.5 wt.%, carbon (0.5-3 wt.%) and/or a carbon source material that supplies free carbon in the sintering process, and a nitrogen-containing additive. The process comprises sintering a powder body in an inert gas atmosphere at a pressure of 1-100 mbar and at a temperature of 2000-2200[deg] C, and performing a gas pressure sintering or a sintering-hot-isostatic press in a nitrogen-containing atmosphere. The powder body: comprises silicon carbide (88 wt.%), a boron-containing additive such as boron carbide in which boron is present in an amount of 0.1-1.5 wt.%, carbon (0.5-3 wt.%) and/or a carbon source material that supplies free carbon in the sintering process, a nitrogen-containing additive in which nitrogen is present in an amount of 0.01-2.3 wt.%, an aluminum-containing additive in which aluminum is present in an amount of 0.01-2 wt.%, and a temporary process auxiliary material; and is prepared by mixing starting materials together in an aqueous solution and drying to form a shaped body. The aluminum-containing additive is included in the powder body only when the powder body contains the nitrogen-containing additive. An independent claim is included for a silicon carbide based ceramic sintered body.