Phosphorus oxychloride remover for phosphorus diffusion furnace

Abstract

The invention discloses a phosphorus oxychloride remover for a phosphorus diffusion furnace, which comprises a buffer box and an exhaust tube, wherein the buffer box comprises a square buffer box body; a Teflon coating is applied onto the inner wall of the buffer box; the back side wall of the buffer box body is provided with a furnace tube opening; the front side of the buffer box body is open and is provided with an air-tight door; the right side of the air-tight door is hinged with the buffer box body; a locking structure is arranged between the left side of the air-tight door and the buffer box body; the air-tight door is provided with a diversion structure; the right side wall of the buffer box body is provided with an exhaust tube opening; the exhaust tube is a U tube; one end of the exhaust tube is provided with an air inlet, and the other end of the exhaust tube is provided with an air outlet higher than the air inlet, and connected with an exhaust fan; the furnace tube of the phosphorus diffusion furnace extends into the buffer box through the furnace tube opening; and the air inlet of the exhaust tube is communicated with the buffer box through the exhaust tube opening. The invention can quickly cool exhaust gas discharged from the diffusion furnace tube by using natural air and misty dilute ammonia water so as to avoid melting the Teflon coating of the exhaust tube, and can also quickly liquefy the phosphorus oxychloride in the exhaust tube.

Description

technical field

[0001] The invention relates to the field of manufacturing semiconductor discrete devices and solar cells. Background technique

[0002] Phosphorus diffusion is a necessary process for manufacturing PN junctions of semiconductor discrete devices, integrated circuit chips and solar cells. At present, the technology used in this process is thermal diffusion technology. Semiconductor discrete devices are mainly used to manufacture diodes, triodes, power devices, IGBTs and thyristors, etc. This series of products has sales of tens of billions in China, and the production capacity is very large. On the other hand, as the use of solar cells, silicon wafers are also widely used. More than 70% of solar cells in the world use silicon wafers as cells. In 2011, the production capacity of 25GW has been achieved, and the polycrystalline consumption has reached 180,000 tons, which is six times the semiconductor consumption, so the output of solar energy is greater than th...

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