A preliminary screening method and device for silicon carbide crystal ingots

Abstract

The present invention provides a preliminary screening method and device for a silicon carbide crystal ingot, the method comprising the following steps: (1) grinding or cutting the surface of the silicon carbide crystal ingot to obtain a transparent or translucent silicon carbide crystal ingot; (2) Use an ultraviolet light source to irradiate the silicon carbide ingot to obtain the light transmission wavelength of the silicon carbide ingot, compare the light transmission wavelength with the standard color wavelength range to determine whether the micropipe density or inclusion density is qualified, and screen to obtain the micropipe The silicon carbide crystal ingot with qualified density or inclusion density is carried out in the next step; the standard color wavelength is the light-transmitting color wavelength of a standard silicon carbide crystal ingot with qualified micropipe and inclusion density after being irradiated with the same ultraviolet light source range. After grinding and cutting the silicon carbide ingot, the degree of visualization is improved, and the silicon carbide ingot with qualified micropipe density or inclusion density is screened by ultraviolet irradiation, which improves the accuracy of the initial screening and reduces the cost of subsequent processing. Detection of work intensity.

Description

technical field [0001] The present application relates to a preliminary screening method and device for silicon carbide crystal ingots, belonging to the technical field of semiconductor material processing equipment. Background technique [0002] After the silicon carbide crystal ingot is prepared, it needs to go through subsequent processing, quality inspection and other steps, and the products that pass the quality inspection can be further used. Since the crystal ingot needs to be sliced ​​during processing, not only the workload is heavy; but also if the defective products fail to pass the quality inspection, the overall utilization of the defective products is limited because they have already been sliced. [0003] After the silicon carbide crystal ingot is opened, human judgment can be carried out, and preliminary screening can be carried out to remove obviously unqualified products, which can reduce the workload of subsequent processing and quality inspection. Howeve...

AI Technical Summary

Problems solved by technology

However, for silicon carbide ingots, the visibility is low, and human judgment is difficult, and at the same time, judgment errors are prone to occur.

The existing silicon carbide ingots need to be processed and sliced, and all the obtained wafers enter the quality inspection, remove the unqualified products and keep the qualified products, and the work intensity is relatively high.

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