Thermal field for improving growth of zone-melting silicon and single crystal silicon

Abstract

The invention provides a thermal field for improving the growth of zone-melting silicon and single crystal silicon, and the thermal field comprises a coil main body and a cooling water pipe, wherein the cooling water pipe is embedded into the coil main body by welding, and the coil main body is a panel coil, and the upper surface of the coil main body is sunken towards the inner part of the coil to form a staircase structure symmetrical about the center, and the edge of the step of the outermost layer of the staircase structure is provided with a groove along the periphery direction. According to the skin effect of a current and the corner effect of a magnetic field, the density of a magnetic induction line at the place of the groove is increased by virtue of the groove design of the thermal field, and the magnetic field is strengthened, so that the purpose of effectively melting silicon projections is achieved, and the growth stability of the silicon single crystal is improved.

Description

technical field [0001] The invention belongs to the field of zone-melting silicon single crystals, and in particular relates to a thermal field for improving the growth of zone-melting silicon single crystals. Background technique [0002] Single crystal silicon growth mainly includes the Czochralski method and the zone melting method. In the process of zone melting silicon single crystal growth, cylindrical polycrystalline material needs to be used, and the roundness of polycrystalline bar material is required to be relatively high. If the bar has some ellipticity or the surface is not smooth enough, and the deviation between the coil and the feeding material during the crystal pulling process will cause silicon thorns to appear on the polycrystalline material, which is not easy to melt, causing discharge, affecting the pass rate and utilization rate and causing unnecessary losses. . With the development of power electronic devices and the increasingly fierce market compe...

AI Technical Summary

Problems solved by technology

[0003] The disadvantages of conventional coils are: the magnetic field lines are dense only at the coil seams, and as the diameter of the polycrystalline material increases, the effect of melting the silicon thorns only by the main seam is not very good, and the surface smoothness of the polycrystalline material and the roundness of the polycrystalline material are required very high

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