Apparatus for realizing automatic ending of crystal pulling

Abstract

The invention discloses an apparatus for realizing the automatic ending of crystal pulling. The apparatus comprises an ending signal window and a high resolution CCD camera. The ending signal window is arranged on the lateral side of the lower furnace chamber of a single crystal furnace. The CCD camera is movably arranged on a position corresponding to the ending signal window, and the signal output terminal of the CCD camera is connected to an industrial control computer and PLC. The provided apparatus can realize the visualization and automation of whole ending process of silicon crystal pulling. The stability and success rate of the ending of crystal pulling are largely improved. The economic loss caused by artificial operation in the ending process is reduced. The production efficiency of CZ silicon mono-crystal is largely improved, and the human cost is saved.

Description

technical field [0001] The invention relates to a device for realizing automatic finishing of Czochralski single crystal, belonging to the technical field of Czochralski single crystal. Background technique [0002] The Czochralski method is a method in which a rotating seed crystal is pulled from a melt in a crucible to prepare a single crystal, also known as the Czochralski method. The principle is: the polycrystalline silicon material is heated and melted, and after the temperature is suitable, the drawing of a single crystal ingot is completed through the steps of immersing the seed crystal, welding, seeding, shouldering, turning the shoulder, equal diameter, and finishing. . [0003] The role of the finisher is to prevent dislocation back delay. During the crystal pulling process, when the dislocation-free growth state is interrupted or the crystal pulling is completed and the crystal suddenly leaves the liquid surface, the grown dislocation-free crystal is subject to...

AI Technical Summary

Problems solved by technology

This approach has two disadvantages: on the one hand, the finishing process cannot be visualized

In the early and middle stages of closing, the speed of the closing process can only be judged by the experience of the operator, and then an appropriate pulling speed can be given; in this way, the closing process has a strong dependence on the personal skills of the operator, and it is easy to produce closing cards, closing On the other hand, with the continuous development of silicon single crystals in the direction of large diameters, the tailing time is greatly extended

The human cost of the manual intervention finishing method continues to increase, and the probability of incomplete tailing is further increased, which in turn reduces the production efficiency of Czochralski silicon single crystal and increases production costs

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