Czochralski method for growing long-lifetime P-type boron-doped silicon single crystal

Abstract

The invention relates to a Czochralski method for growing a long-lifetime P-type boron-doped silicon single crystal, which is a special Czochralski silicon single crystal growing method for growing a long-lifetime P-type silicon single crystal. A P(100) silicon single crystal grown with the method under a phi 20'' thermal device with the charging capacity of 70-90kg has the diameter of phi 150-200cm, the electrical resistivity of 3-20 ohm.cm and the lifetime value larger than 300 microseconds. By means of the method provided by the invention, the minority carrier lifetime of the crystal is prolonged, which not only indicates that the microcosmic crystal lattice completeness is greatly improved but also indicates that the contamination and the diffusion pollution of impurities to a crystalbar during crystal growth are greatly decreased. If the P-type silicon wafer is applied to solar power generation, photoelectric conversion efficiency can be greatly improved, and if the P-type silicon wafer is applied to an integrated circuit substrate, relevant quality parameters of a product can be greatly improved. The method provided by the invention ensures that the minority carrier lifetime of the integral crystal bar is greatly prolonged, and the minority carrier lifetime of a cross section tends to be distributed uniformly, therefore, the product upgrade of a single crystal silicon lattice with high completeness and high purity is realized, and the method has a wide application range.

Description

technical field [0001] The invention relates to a method for growing a P-type high-life boron-doped silicon single crystal by a Czochralski method, specifically a method for growing a P-type (doped with boron), <100> crystal orientation, a resistivity of 3-20Ω·cm, and a high lifespan by a Czochralski method. method for silicon single crystals. Under the condition of implementing the process of the present invention, not only the overall minority carrier life of the crystal rod is greatly improved, but also the distribution of the minority carrier life of the section tends to be uniform, and the product upgrade with high integrity and high purity of the single crystal silicon lattice is realized, which is much better than the conventional process. Great development. The improvement of the crystal minority carrier lifetime by the invention not only shows that the integrity of the microscopic lattice is greatly improved, but also shows that the contamination of the crystal...

AI Technical Summary

Problems solved by technology

[0003] The P silicon single crystal ingot produced by the conventional method has the following characteristics: the overall minority carrier lifetime is low (the lifetime of the single crystal head and tail skin cannot reach 300 microseconds, and most of them are less than 50 microseconds); the minority carrier lifetime distribution of the crystal rod section is uneven ( The surface of the ingot or the edge of the section of the ingot is far below the center)