A silicon carbide crystal growth method and device

Abstract

The present invention provides a silicon carbide crystal growth method and device, the method comprising: (1) assembly stage: (2) sublimation stage: controlling a plurality of partitions to rotate between the plurality of partitions and the inner wall of the partition and the cavity There is no gap between them, the first crucible is separated from the second crucible, and the silicon carbide raw material is heated to sublimate; (3) Crystal growth stage: control multiple partitions to rotate between multiple partitions and / or the inner wall of the partition and the cavity There is a gap between them, and the second crucible communicates with the first crucible through the gap, and the heating makes the silicon carbide raw material atmosphere pass through the gap to the seed crystal for crystal growth. By controlling the rotation of multiple partitions, the first crucible is separated from the second crucible, and the sublimated atmosphere of the silicon carbide raw material cannot be transmitted upwards, so as to avoid the formation of defects affecting the crystal quality and damage and pollution to the seed crystal caused by the unstable atmosphere in the early stage of growth. And the separator blocks the heat radiation from the raw material to the seed crystal, avoiding the sublimation of the seed crystal surface caused by the lack of silicon carbide atmosphere supplement during impurity removal.

Description

technical field [0001] The invention relates to a silicon carbide crystal growth method and device, belonging to the technical field of silicon carbide crystal growth. Background technique [0002] Silicon carbide (SiC) crystals have excellent semiconductor physical properties such as high thermal conductivity, high breakdown voltage, extremely high carrier mobility, and high chemical stability. They can be made into high-frequency, High-power electronic devices and optoelectronic devices have great application value in the fields of national defense, high technology, industrial production, power supply, and power transformation, and are regarded as the third-generation wide-bandgap semiconductor materials with great development prospects. [0003] The growth process of silicon carbide crystals grown by PVT method is carried out in a closed graphite crucible. The silicon carbide powder (or silicon, carbon solid mixture) as the growth source is placed at the bottom of the cru...

AI Technical Summary

Problems solved by technology

Unstable atmosphere transmission will affect the nucleation of silicon carbide atmosphere on the seed crystal, which can easily induce defects such as polymorphism and dislocation, which will affect the quality of crystallization

At the same time, some impurities in the powder will be sublimated below the growth temperature of silicon carbide, and the transfer to the surface of the seed crystal will induce nucleation problems

The silicon carbide crystal growth methods and devices in the prior art cannot completely block the upward transportation of the silicon carbide atmosphere in the early stage of crystal growth, thereby affecting the nucleation of the silicon carbide atmosphere on the seed crystal, which easily induces defects such as polymorphism and dislocation, and affects the crystal. the quality of

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