Method of quickly entering seeding process in production of monocrystalline silicon by large thermal field czochralski technique

Abstract

The invention discloses a method of quickly entering a seeding process in production of monocrystalline silicon by large thermal field czochralski technique. The method includes: after a silicon material melts, an upper shaft tungsten wire rope drives seed crystals to rotate, enabling a quartz crucible to do reverse rotation, at the same time lowering the upper shaft tungsten wire rope to contactthe seed crystals with molten silicon, then adjusting the power of a heater to seek the seeding temperature, when the heater maintains certain power for a period of time and the seed crystals are notfused, entering a steady temperature state; under the steady temperature state, lowering the seed crystals to the position of primary seed crystals to melt previously growing monocrystalline silicon,and then accelerating the reverse rotation speed of the quartz crucible to enter the seeding process. The method of quickly entering the seeding process in production of monocrystalline silicon by large thermal field czochralski technique provided by the invention can greatly shorten the temperature searching time and ensure slow decrease of the molten silicon temperature during seeding, thereby avoiding the problem of dislocation caused by thermal stress and surface tension of seed crystals due to rapid change of the molten silicon temperature, and reaching the effects of rapid entry of seeding and shortening of invalid labor hour.

Description

technical field [0001] The invention belongs to the technical field of monocrystalline silicon production by the Czochralski method, and in particular relates to a method for rapidly entering a crystal seeding process when producing monocrystalline silicon by the Czochralski method with a large thermal field. Background technique [0002] In the process of producing monocrystalline silicon by the Czochralski method, the brief process is to put the raw silicon material into the quartz crucible in the single crystal furnace, seal the furnace body and then pass in the protective gas, and heat the material block to Melting at about 1400°C, the crystal pulling process is completed through operations such as seeding, shoulder laying, shoulder turning, equal diameter, and finishing. [0003] In order to save the cost of producing monocrystalline silicon by the Czochralski method, increase the production capacity and feeding amount of the Czochralski method, generally adopt the meth...

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to provide a method for quickly entering the seeding process when producing single crystal silicon by using the large thermal field Czochralski method, which avoids the problem of dislocations caused by thermal stress and surface tension of the seed crystal due to rapid temperature changes of molten silicon