Growth method of granular SiC (silicon carbide) single crystals

Abstract

The invention provides a growth method of granular SiC (silicon carbide) single crystals to solve problems in the prior art. A porous graphite plate is coated with polymers with high carbon content, granulated SiC seed crystals are uniformly arranged on the surfaces of the polymers, the non-coated surface of the porous graphite plate is fixed on an upper cover of a graphite crucible, SiC powder is put at the bottom of the graphite crucible, the upper cover of the crucible and the SiC powder are arranged oppositely, the graphite crucible is put in an induction heating furnace for growth of SiC single crystals, the growth temperature ranges from 1,800 DEG C to 2,400 DEG C, the growth pressure ranges from 1*10<-4> Pa to 1*10<4> Pa, and the granular SiC single crystals are obtained. Accordingly, the granular SiC single crystals can be obtained directly, cutting operation is avoided, the granular SiC single crystals can be directly taken as raw materials of SiC gems, the productivity is improved, and the production cost is reduced.

Description

technical field [0001] The invention relates to the application field of high-frequency devices, and mainly relates to a method for growing a granular silicon carbide single crystal. Background technique [0002] The nature of the crystal itself determines whether the crystal is suitable as a gemstone raw material, mainly including refractive index, hardness and stability. The index of refraction reflects the crystal's ability to refract light, and gemstones made of materials with a high index of refraction can sparkle and show luster in sunlight. Hardness reflects the ability of gemstones to resist scratching, while stability ensures the long-term wearing and use of gemstones. SiC has a high refractive index (2.5-2.7), high hardness (Mohs hardness 8.5-9.25), and SiC is extremely stable and can withstand high temperatures above 1000°C in air, so SiC crystals are very suitable for making gems. [0003] A common method for the preparation of bulk SiC single crystals is the p...

AI Technical Summary

Problems solved by technology

However, this method in the prior art has the following disadvantages: the SiC crystal has high hardness, and the wire cutting cycle is long, which reduces the production efficiency; the SiC crystal cutting process needs to consume cutting consumables and the SiC crystal will be lost during the cutting process, which increases the production cost.

Due to the high hardness of SiC, it is very time-consuming to cut the bulk SiC single crystal into granular rough gemstones, resulting in low production efficiency

In addition, due to the inevitable cutting loss during the cutting process, the utilization efficiency of bulk SiC single crystal is reduced, which increases the production cost.

Images