System and method for preparing electronic-grade polycrystalline silicon for low-internal-stress zone melting

Abstract

The invention discloses a system and a method for preparing electronic-grade polycrystalline silicon for low-internal-stress zone melting. The system for preparing the electronic-grade polycrystallinesilicon for low-internal-stress zone melting comprises: a polycrystalline silicon reduction furnace, wherein the polycrystalline silicon reduction furnace is internally provided with a bottom plate,a plurality of graphite chucks and a plurality of pairs of silicon rods, the silicon rods are arranged on the bottom plate through the graphite chucks, the plurality of pairs of silicon rods comprisea plurality of pairs of inner ring silicon rods and a plurality of pairs of outer ring silicon rods, each pair of silicon rods comprises a cross beam and two rod bodies; a plurality of inner ring silicon rod diameter detection units, wherein the inner ring silicon rod diameter detection units are connected with the inner ring silicon rods; a trichlorosilane-hydrogen feeding pipeline which is connected with the polycrystalline silicon reduction furnace, and the trichlorosilane-hydrogen feeding pipeline is connected with the polycrystalline silicon reduction furnace; and a plurality of dichlorosilane-hydrogen feeding nozzles, wherein the dichlorosilane-hydrogen feeding nozzles are arranged on the connecting line of the cross beam of the inner ring silicon rod and the center of the bottom plate. The system can be used for producing electronic-grade polycrystalline silicon products with relatively small internal stress for cell melting.

Description

technical field [0001] The invention relates to the technical field of polysilicon production, in particular, the invention relates to a system and a method for preparing electronic-grade polysilicon for low internal stress zone melting. Background technique [0002] Zone-fused monocrystalline silicon is a key material for electronic power devices. Target products include ordinary thyristors (SCR), power transistors (GTR), turn-off thyristors (GTO) and the third generation of new power electronic devices - power field effect transistors ( MOSFET) and insulated gate bipolar transistor (IGBT) and power integrated circuit (PIC), etc., are widely used in high voltage direct current transmission, static var compensation, electric locomotive traction, AC and DC power transmission, electrolysis, excitation, electric heating, high Performance AC and DC power supply and other power systems and electrical engineering. [0003] Compared with Czochralski single crystal silicon, zone me...

AI Technical Summary

Problems solved by technology

Among them, silicon rods with high thermal stress or hidden cracks are easy to burst in the subsequent machining process, or in the process of single crystal drawing, due to the partial heating of silicon rods by zone melting coils to induce bursts, damage to equipment Hazards caused by safe operation

It can be seen that the existing methods for preparing polysilicon for zone melting still need to be improved.

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