Apparatus for automatically detecting fusion jointing state of crystal and fusion silicon liquid level in vertical pulling type single crystal furnace

Abstract

The invention relates to a straight pulling type single crystal production technology, aiming at providing an automatic detecting device for the fusion state of the single crystal and a silica fused liquid surface in a straight pulling type single crystal furnace. The device comprise a pulley, a sector conductor, a cable rope pipe externally coated with insulation materials, a steel cable, a metal seedholder, a quartz crucible, a graphite crucible, and a crucible push-off pin and the sector conductor of conductive materials; wherein, the steel cable, the pulley, a furnace body and a detecting warning circuit form a loop. The device can automatically detect the fusion state of the crystal and the liquid surface, and judge the fusion time; avoid the fusion accidents of the seedholder resulted from seedholder over-descending due to human behaviors; can monitor the fusion state of the crystal and the liquid surface in real time during the whole process, and warn the separation of the liquid surface in time; reduce labor intensity, improve the automation degree of the straight pulling type single crystal furnace and provide key techniques for the full automatic design of the single crystal furnace.

Description

technical field [0001] The invention relates to a Czochralski single crystal production technology, in particular to an automatic detection device for the welding state of crystal and molten silicon liquid surface in a Czochralski single crystal furnace. Background technique [0002] In the production process of Czochralski monocrystalline silicon, it needs to go through many process steps from polycrystalline silicon material to pulling out monocrystalline silicon rods. It is necessary to monitor the state of the fusion between the crystal and the molten silicon surface. The seeding process is a growth process of fine grains. Before the seeding starts, the seed rod needs to be slowly inserted into the molten silicon liquid surface. When the liquid surface temperature reaches the requirements of fine grain growth, the liquid surface temperature and the increase of the seed crystal can be controlled. speed to achieve fine grain growth. During the descent of the seed crystal...

AI Technical Summary

Problems solved by technology

While the seed crystal is descending, it is necessary to judge the welding state of the seed crystal and the molten silicon liquid surface, and stop the descent when it is found to be welded. If the seed crystal is too low, it will cause the accident of complete melting of the seed crystal or melting of the seed crystal chuck.

In actual production, the descending process of the seed crystal must be manually operated by the operator, and the welding state can be judged by the naked eye, which increases the labor intensity and has potential accidents caused by human factors.

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