Crucible structure for growing 6-inch SiC single crystal by expanding diameter of 4-inch seed crystal

The utility model discloses a crucible structure for growing a 6-inch SiC single crystal through diameter expansion of a 4-inch seed crystal, the crucible structure comprises a crucible body, a crucible cover and a diameter expansion structure, the diameter expansion structure is detachably mounted on the crucible body, the diameter expansion structure sequentially comprises a first mounting part, a connecting part and a second mounting part, the first mounting part is connected with the crucible cover, the second mounting part is connected with the crucible body, and the connecting part is used for placing 4-inch seed crystals. According to the utility model, the quality of 6-inch single crystals is improved. The defects of the 6-inch single crystal grown through diameter expansion are much fewer than those of outsourced 6-inch single crystals, for example, the defects of phase change, edge polycrystal, inclusions, TSD, TED, BPD and other depths of the 6-inch single crystal grown through diameter expansion c