Charging device and charging method for growing SiC single crystals by PVT (physical vapor transport) method

Abstract

The invention discloses a charging device and charging method for growing SiC single crystals by a PVT (physical vapor transport) method, and belongs to the field of crystal growth. The device comprises a crucible and an auxiliary charging device for separating the side part and the middle part of the internal space of the crucible. According to the charging method, raw materials with different particle sizes are placed in different positions in the crucible; different functions are achieved; large-particle raw materials are located on the edge, thus the heat conductivity of a raw material area on the inner side of the crucible can be increased, and raw material carbonization generated by local overheating of the edge is reduced; and small-particle materials are located on the surface, thejoint filling capacity is high, and bottom carbonized C particles can be effectively prevented from being conveyed upwards. By adopting the charging method, inclusions in the crystals can be effectively reduced, the crystal quality can be improved, the crystals can be enabled to grow thicker, the yield can be increased, and meanwhile, no new material or new device is introduced, and the production cost is not additionally increased.

Description

Technical field [0001] The invention relates to the field of crystal growth, in particular to a charging device and a charging method for growing SiC single crystals by a PVT method. Background technique [0002] As a third-generation semiconductor material, SiC has many excellent properties such as wide band gap, high thermal conductivity, high electron saturation migration rate, and high breakdown electric field. Silicon carbide semiconductor has become an internationally recognized leader in power electronics, especially large The best electronic materials for the next 50 years of power power electronics can be used to make a new generation of high-efficiency and energy-saving power electronic devices, which are widely used in various fields of the national economy. [0003] In terms of SiC single crystal growth technology, the physical vapor transport (PVT) method is mainly used in the world to grow SiC single crystals. However, in the process of growing SiC single crystal by ...

AI Technical Summary

Problems solved by technology

However, there will be SiC crystal crystallization at the porous graphite network in the growth chamber, which blocks the upward transport of SiC gas phase components in the powder, greatly reduces the growth rate, and affects the yield.

[0005] A large part of the reason for the formation of C inclusions is that the charging method is unscientific, and the method of loading raw materials with different particle sizes into the crucible is unreasonable, so it is very necessary to optimize the charging method to reduce the formation of inclusions in the crystal

Images