Socket joint type silicon core lapping structure and method capable of increasing contact area and reducing electric resistance

Abstract

The invention belongs to a silicon core lapping method in a polysilicon production process by a Siemens method, and particularly relates to a socket joint type silicon core lapping structure and method capable of increasing contact area and reducing electric resistance. Both sides of a horizontal silicon core (2) are respectively provided with a lapping surface (6) formed by a bifacial trough (5), or provided with an end U bayonet (7); and the upper ends of two vertical silicon cores (3) are respectively provided with a lapping surface (6) formed by a bifacial trough (5), or provided with an end U bayonet (7). The lapping method comprises the following steps: preprocessing the horizontal silicon core and vertical silicon cores; and after lapping the silicon cores, putting the silicon cores in a reducing furnace, and introducing hydrogen and trichlorosilane to carry out reducing reaction, so that required polysilicon forms the silicon core on the silicon core surface, thereby implementing multiple reduction processes of polysilicon. By using the invention, the lap joint of the silicon cores has large contact surface, and the step of drawing silicon core spherosome in all existing techniques is not needed, thereby ensuring the increase of yield.

Description

【Technical field】 [0001] The invention belongs to a silicon core overlapping method in the process of producing polysilicon by the Siemens method, in particular to a plug-in silicon core overlapping structure and method which can increase the contact area and reduce resistance. 【Background technique】 [0002] At present, silicon core bonding technology is a very important technology in the process of polysilicon production by Siemens method. It is mainly used in a link of polysilicon production, that is, the reduction reaction process. The principle of the reduction reaction process is: the reduction reaction is carried out in a closed reduction furnace, and several closed loops are formed by lapping silicon cores in the reduction furnace before loading the furnace, which is the "bridge" in the jargon. "; each closed circuit is composed of two vertical silicon cores and one horizontal silicon core; the two vertical silicon cores of each closed circuit are respectively connec...

AI Technical Summary

Problems solved by technology

[0003] The Chinese patent that was first applied for: discloses a hole-type silicon core lapping method that can effectively increase the contact area and reduce resistance. This patent proposes a lapping method for spherical silicon cores. Silicon core spheres are arranged at both ends of the core, and jacks are respectively set at the lower part of the two silicon core spheres, and the plugs at the upper end of the vertical silicon core are matched with the jacks to form a connection method that increases the contact area and reduces resistance. However, in practical applications, it is found that when drilling holes on the horizontal silicon core sphere, it will often cause the horizontal silicon core sphere to crack, or even break, and the yield is relatively low, which increases the processing cost; End-drawing a sphere is also a relatively complex and costly process. This process is not only complicated, but also when drawing a horizontal silicon core sphere, if you are not careful, the high-frequency coil will contact the silicon core and cause ignition. The occurrence of the phenomenon may even cause the high-frequency coil to be scrapped, and affect the progress of the process. The drawing process must be stopped, and the next drawing process will be carried out by replacing the high-frequency coil. Among them, when the equipment is turned on again during the shutdown, it is necessary to prevent raw materials from The rod is oxidized during the drawing process, and the seed crystal must be replaced with a new one. At the same time, the silicon core furnace must be vacuumed, flushed with protective gas, and heated.

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