The theory on the ceramic crucible size can expand without limit, only limited size is limited to the practical application of ingot furnace. The greater the silicon ingot, the better the quality of the product. The defects and impurities that affect the quality of the ingot will tend to the edge of the ingot. A large size of silicon ingot can produce more and more useful, better quality products, the higher the material rate. Therefore, the international trend tends to produce a larger size of silicon ingot. The large size of the quartz crucible is 32 (784mm).
At present, the weight of the domestic cast polysilicon is generally 400~450kg, the size is 880mm * 880mm * 400mm.
The main difference between the application of the ceramic crucible and the quartz crucible in the application of the polysilicon is the difference of its thermal performance. Some thermal properties of the two different, such as, linear expansion coefficient: ceramic crucible and quartz glass crucible of linear expansion coefficient is very low, linear expansion coefficient is very low for 0.6x10-6/, near zero expansion;
Thermo resistance: ceramic and quartz glass crucible with extremely low expansion coefficient, the onetime capital has very good resistance to thermal shock. The sample is heated to 1000 DEG C water will not burst again into 20. It is usually used to measure the thermal shock resistance of the water by the times of the repeated heating. The main difference is that the softening temperature and the loss of. |