Artificial synthetic method of high-pure SiC power for semiconductor single-crystal growth

The invention provides a method for artificially synthesizing high-purity carborundum powder used for growing semiconductor single crystal. The method comprises the following steps of: (1) taking Si powder and C powder according to a mol ratio of 1 to 1; (2) putting the Si powder and the C powder into a crucible after the Si powder and the C powder are mixed uniformly, putting the crucible in a medium frequency induction heating furnace, vacuumizing a growth chamber of the heating furnace, and increasing the temperature to 1000 DEG C; charging high-purity argon gas, helium gas or mixture of argon gas and hydrogen into the growth chamber, heating the mixed gas up to a synthetic temperature of 1000 DEG C, and reducing the synthetic temperature to room temperature after maintaining for certain reaction time; (3) uniformly mixing powder of a product acquired in the primary synthesis, heating the product up to a secondary synthetic temperature of between 1600 and 2000 DEG C, synthesizing for 2 to 10 hours, and reducing the synthesized product to the room temperature to acquire high-purity SiC powder lot applicable to the semiconductor SiC single crystal growth. The method adopts a secondary synthetic method, not only can ensure that Si and C simple substance which are remained during the primary synthesis can completely react, but also can effectively remove most impurity elements carried in the Si powder and the C powder.