Centrally symmetric silicon carbide (SiC) single crystal growing device and method

Abstract

The invention relates to a centrally symmetric silicon carbide (SiC) single crystal growing device. The growing device comprises a graphite crucible with a cover, wherein the bottom of the graphite crucible is connected with a rotating system which rotates the graphite crucible; the rotating system comprises a rotating tray, a center rotating rod and a driving device which drives the center rotating rod to move actively; the driving device is in sealing connection with a vacuum growth cavity by a tee connector; the center rotating rod passes through the tee connector to be connected with the driving device. According to the growing device disclosed by the invention, the bottom of the graphite crucible is connected with the rotating system which rotates the graphite crucible, when the rotating system is used, the rotation speed of the center rotating rod is 1 to 60 revolutions per minute; a non-centrosymmetric thermal field caused by spiral induction coils and thermal insulation is avoided; a centrosymmetric thermal field is constructed, and the transmission of substances is in central axial symmetry, so that the obtained crystal is centrally symmetric; the thicknesses of all edges are identical, and the use ratio of crystal materials is improved.

Description

Technical field [0001] The invention relates to a SiC single crystal growth device and method with central symmetry, belonging to the technical field of crystal growth equipment. Background technique [0002] Compared with many other semiconductor single crystal materials, SiC crystal has high hardness (second only to diamond), high thermal conductivity (4.9W / cm·K), and low thermal expansion coefficient (3.1-4.5×10-6 / K) , Wide band gap (2.40-3.26eV), high saturation drift speed (2.0-2.5×107cm / s), strong critical breakdown field (2~3×106V / cm), high chemical stability, strong radiation resistance And other excellent performance. These excellent properties make SiC crystals have broad application prospects under high temperature, high pressure, and strong radiation working environment, and will have an important impact on the development of future electronic information industry technology. [0003] Physical Vapor Transport (Physical Vapor Transport-PVT) is the current mainstream me...

AI Technical Summary

Problems solved by technology

However, due to the following reasons in the traditional SiC crystal growth device, the grown crystal does not have central symmetry, so that the thickness of the crystal edge is not equal, which greatly reduces the utilization rate of the crystal material; 1) The induction coil of the traditional SiC crystal growth device is Helical, its shape does not have central axis symmetry; induction heating will cause the temperature field generated by the crucible heating element to have non-central axis symmetry, and make the material transmission present non-central axis symmetry

2) Insulation material does not have central axis symmetry

Although the design of the insulation layer can suppress the non-central axis symmetry to a certain extent and reduce the radial temperature gradient, it cannot change the asymmetry of the coil, and the grown crystal still has central symmetry, and with The insulation layer needs to be replaced regularly, and the repeatability is poor

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