Polycrystalline silicon ingot furnace

Abstract

The invention discloses a polycrystalline silicon ingot furnace which can enable the resistivity of a cast ingot to be distributed uniformly. A stop block for sealing a gas outlet is arranged at the gas outlet of a gas inlet pipe of the polycrystalline silicon ingot furnace, a plurality of spiral holes with the same helical direction are formed in the stop block, the plurality of the spiral holes are arranged around the central axis of the gas inlet pipe, inlets of the spiral holes are positioned on the upper surface of the stop block, and outlets of the spiral holes are positioned on the lower surface of the stop block. After argon gas passes through the spiral holes, the gas outlet way of the argon gas is changed from original direct blowing to rotating gas outlet, and the argon gas which is sprayed out of the spiral holes in a rotating manner can drive a silicon solution in a crucible to rotate, so that impurities contained in the silicon solution can be fully diffused in the silicon solution, the distribution of liquid-phase components is uniform, and the uniform distribution of the resistivity of the cast ingot is ensured; furthermore, the stirring of the silicon solution in the crucible can enable the volatile impurities contained in the silicon solution to be volatilized as soon as possible so as to ensure the quality and performance of the cast ingot. The polycrystalline silicon ingot furnace is suitable for popularization and application in the field of polycrystalline silicon production equipment.

Description

technical field [0001] The invention relates to the field of polysilicon production equipment, in particular to a polysilicon ingot casting furnace. Background technique [0002] Solar cells can convert light energy into electrical energy, which is a key point in the development of a modern energy-saving society. According to different substrate materials, existing solar cells are divided into polycrystalline silicon solar cells, monocrystalline silicon solar cells and quasi-monocrystalline silicon solar cells. Among them, the conversion efficiency of monocrystalline silicon solar cells is high, but the production cost is also high. The conversion efficiency of polycrystalline silicon solar cells is 1%-2% lower than that of monocrystalline silicon solar cells, but its production cost is also low. The battery is a battery between a monocrystalline silicon battery and a polycrystalline silicon solar battery. Comprehensive consideration, the current solar cells on the market ...

AI Technical Summary

Problems solved by technology

However, too long time after the silicon material is melted will lead to the destruction of the silicon nitride coating inside the crucible. Therefore, after the silicon material is melted, it will start to cool down to the crystal growth temperature. The free volatilization time is short, and most of the volatile impurities Before volatilization, it enters the crystal growth stage, and the impurities are solidified in the silicon ingot. At this time, the viscosity of the silicon liquid is relatively high, and the non-volatile impurities and volatile impurities are not fully diffused in the silicon solution. Uneven distribution leads to impurity-enriched areas in the solidified ingot, resulting in uneven distribution of the resistivity of the ingot, which seriously affects the quality and performance of the ingot itself

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