Novel crucible capable of reducing inclusions in silicon carbide single crystals and method for growing single crystals by using crucible

Abstract

The invention relates to a novel crucible capable of reducing inclusions in silicon carbide single crystals and a method for growing single crystals by using the crucible. The novel crucible comprises an outer crucible and a crucible cover, wherein an inner crucible is arranged in the outer crucible; the inner crucible comprises a bottom and a side wall; the side wall is a double-layer side wall; the double-layer side wall comprises an inner wall and an outer wall; small holes penetrating through the inner wall are formed in the inner wall; an annular end cover for sealing an interlayer between the inner wall and the outer wall is arranged at the upper end opening of the double-layer side wall. The inner crucible of the crucible closes SiC powder, which is located at a high temperature position and is easy to carbonize, in the interlayer between the inner wall and the outer wall of the inner crucible, so that powdered carbonized tiny carbon particles cannot be transported to the surfaces of seed crystals; meanwhile, powder in an inner cavity achieves a filter effect on a pyrolytic gas phase in the interlayer, so that the carbon particles are prevented from being transmitted to the surfaces of the SiC single crystals; therefore, carbon inclusions in the SiC single crystals are greatly reduced, and even in the SiC single crystals with the thickness of 20 mm, still no carbon inclusions are generated.

Description

technical field [0001] The invention relates to a novel crucible for reducing inclusions in silicon carbide single crystals and a method for growing single crystals using the crucible, belonging to the technical field of crystal growth equipment. Background technique [0002] Compared with many other semiconductor single crystal materials, silicon carbide (SiC) crystal has high hardness (second only to diamond), high thermal conductivity (4.9W / cm K), low thermal expansion coefficient (3.1-4.5×10 -6 / K), large band gap (2.40-3.26eV), high saturation drift speed (2.0-2.5×10 7 cm / s), the critical breakdown field is strong (2~3×10 6 V / cm), high chemical stability, strong radiation resistance and other excellent properties. These excellent properties enable SiC semiconductor devices to work in extreme environments of high temperature, high pressure, and strong radiation. They have broad application prospects in the fields of optoelectronics and power electronics, and will have ...

AI Technical Summary

Problems solved by technology

However, the seed crystal axis is suitable for growing silicon carbide in liquid phase, but not suitable for growing high-quality silicon carbide single crystal by physical vapor transport method.

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