Silicon carbide crystal growth method and equipment for supplementing gaseous carbon source and silicon source

Abstract

The invention provides a silicon carbide crystal growth method and equipment for supplementing a gaseous carbon source and a silicon source, the equipment comprises a furnace body, a graphite crucible heater and a growth tank, a porous partition plate is arranged in the graphite crucible and divides the graphite crucible into a crystal growth cavity and a gas diffusion cavity, the height of the crystal growth cavity is defined as M, the upper edge of the gas diffusion cavity is arranged in an area from the position 1/3M above the porous partition plate to the horizontal center line of the porous partition plate, and the bottom of the gas diffusion cavity is fixedly connected with a gas inlet assembly; and the heater is used for uniformly heating the crystal growth cavity. The equipment comprises the crystal growth cavity and the gas diffusion cavity, and components are adjusted by supplementing the gaseous carbon source and the silicon source, so that the balance of the carbon component and the silicon component in the space near a silicon carbide crystal is kept in the crystal growth process, and the defects of spiral dislocation, stacking fault, microtubule and the like of the silicon carbide crystal are avoided, and the utilization rate of silicon carbide raw materials is improved.

Description

technical field [0001] The invention relates to a silicon carbide crystal growth method and equipment for supplementing gaseous carbon sources and silicon sources, and belongs to the technical field of silicon carbide crystal growth. Background technique [0002] The industrial growth of silicon carbide crystals mainly adopts the physical vapor transport (PVT) method, that is, the gas generated by the sublimation and decomposition of silicon carbide raw materials is transported to the seed crystal for recrystallization by heating above 2100 ° C, and silicon carbide (SiC) with a large area is obtained. ) single crystal. [0003] But at high temperature, silicon (Si) element and silicon-rich atomic groups are easier to escape from the raw material and transported into the growth chamber space, so the silicon element in the raw material is faster than the carbon (C) element during the crystal growth process. The carbonization of the raw material (that is, the C content in the ...

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Problems solved by technology

[0003] But at high temperature, silicon (Si) element and silicon-rich atomic groups are easier to escape from the raw material and transported into the growth chamber space, so the silicon element in the raw material is faster than the carbon (C) element during the crystal growth process. The carbonization of the raw material (that is, the C content in the raw material is higher than the Si content), after carbonization, the raw material will produce carbon-rich atomic groups, which will deposit on the crystal to form inclusion defects, and the inclusion defects will further grow into screw dislocations, layer Larger-scale defects such as faults and micropipes seriously affect the crystal quality of silicon carbide, which in turn affects the yield and product quality of downstream processes such as epitaxial process and device process; at the same time, crystal growth must be stopped when the raw material carbonization is serious, resulting in A large amount of waste, the ratio of the weight of crystals obtained in the industry to the weight of raw materials input is less than one-third, and the waste of raw materials is serious

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