Method for preparing transitional metal-doped silicon carbide material through self-propagation high-temperature synthesis

Abstract

The invention provides a method for preparing a transitional metal-doped silicon carbide material through self-propagation high-temperature synthesis. The method comprises the following steps of: taking silica powder, carbon black and ammonium chloride as initiative raw materials of a reaction, wherein the particle size of the silica powder is 200 to 400 meshes, the particle size of the carbon black is 20 to 60nm, and the using amount of the ammonium chloride is 0.5 to 3 percent of the total mass of the silica powder and the carbon black; ball-milling the initiative raw materials of the reaction for 2 to 4 hours; adding transition metal powder in an amount which is 0.5 to 10 percent of the total mass of the silica powder and the carbon black and polytetrafluoroethylene in an amount which is 1 to 20 percent of the total mass of the silica powder and the carbon black into the ball-milled raw materials for secondary ball milling; sieving the raw materials which are subjected to secondaryball milling with a 60-mesh sieve, and placing into a graphite crucible; putting the graphite crucible into a high-pressure reactor, performing vacuum pumping, washing gas, aerating argon under the pressure of between 0.5 and 5MPa, electrifying and igniting, and performing a self-propagation high-temperature combustion synthesis reaction; and performing impurity removal treatment on a material synthesized by the reaction. By the method, production period is short, the process is simple, and controlled doping can be realized.

Description

technical field [0001] The invention relates to the field of preparation of inorganic non-metallic materials, in particular to a method for self-propagating high-temperature synthesis of transition-type metal-doped silicon carbide materials. Background technique [0002] Silicon carbide (SiC) is one of the most mature wide-bandgap semiconductor materials at present. It has excellent properties such as strong oxidation resistance, high temperature resistance, small thermal expansion coefficient, high thermal stability, and high thermal conductivity. Compared with traditional semiconductor materials represented by silicon (Si) and gallium arsenide (GaAs), silicon carbide has the advantages of wide band gap, high thermal conductivity, high saturation electron drift velocity and high bonding energy. More importantly, silicon carbide materials with microwave attenuation properties have been widely used in military fields such as microwave weapons, electronic countermeasures, rad...

AI Technical Summary

Problems solved by technology

At present, silicon carbide doping mostly adopts high-temperature solid-state reaction method, ion implantation method, epitaxy control method, and laser synthesis method. Complex application and promotion

For example, a silicon carbide doping method uses high-temperature solid-state reaction to do manganese (Mn) doped silicon carbide. The mixed powder needs to be pressed into small balls, placed in a corundum tube, and then flushed with high-purity argon after being evacuated. Place it in a furnace at 1000°C for 24 hours, and then sinter at 1450°C for 24 hours to obtain manganese-doped silicon carbide powder. The test period is long and the process is cumbersome.

Another method of silicon carbide doping is to inject vanadium into the surface of silicon carbide to re-epitaxially grow a layer of heavily doped layers, but the process is more complicated and the cost is higher.

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