ZAHNG Fusheng (1989-), male, Ph.D. E-mail: wulizfs@163.com
The micropipe (MP) in silicon carbide (SiC) single crystal substrate is a fatal defect for SiC-based devices, which will seriously affect the yield of SiC power devices. In this paper, the 6 in n-type 4H-SiC single crystals without micropipe defect were prepared by the optimized growth design based on physical vapor transport (PVT) method. The effects of the optimized growth design on the elimination of micropipes were also studied. Based on the principle of crystallography and kinetics, the mechanism of micropipe decomposition and closing is clarified. In summary, the optimized growth design adopted in this paper not only promotes the stability of SiC single crystal growth, but also can improve the crystalline quality of SiC single crystal, and can quickly reduce the density of micropipes. The prepared large size 6 in n-type 4H-SiC single crystals without micropipe defect will be more suitable for making high-voltage and ultra-high-voltage power devices.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |