A Method for Improving Wafer Edge Warpage

Abstract

The present invention relates to the field of semiconductors. A method for improving warping of the edge of a silicon wafer, characterized in that the silicon wafers after slicing are sequentially subjected to the following grinding steps: step 1, grinding the edge of the silicon wafer with a chamfering wheel, performing a chamfering diameter grinding, and a chamfering The diameter grinding amount is A, and A is 230μm-270μm; Step 2, conduct a double-sided grinding with a wide grinding wheel, and the wide removal amount of a double-sided grinding is B, and B is 28μm-32μm; Step 3, use a chamfering grinding wheel Grinding the edge of the silicon wafer, performing secondary chamfering diameter grinding, the secondary chamfering diameter grinding amount is C, and C is 730μm-770μm; step 4, perform secondary double-sided grinding with a wide grinding wheel, and the secondary double-sided grinding The wide removal amount is D, and D is 33μm-37μm; A+C=1000μm, B+D=65μm. After adopting the above-mentioned grinding steps, the wide-width problem caused by the warping of the edge of the silicon wafer is effectively improved.

Description

technical field [0001] The invention relates to the field of semiconductors, in particular to a method for grinding silicon wafers. Background technique [0002] The position where the slice warpage is too large is mainly concentrated near the entry point and exit point of the steel wire. According to past experience and the current level of wire cutting, edge warping is difficult to be further effectively improved. [0003] The traditional method of chamfering silicon wafers is to directly grind the diameter of the metal grinding wheel, and the removal amount is about 1000um, and the diameter is ground to the specification requirements. According to this traditional processing method for chamfering, the defect rate of edge warping is high, because edge warping will cause a large difference in the width of the warping point during chamfering. The width is an extremely important parameter index and rigid requirement for customer requirements. Generally, the width of the sam...

AI Technical Summary

Problems solved by technology

According to this traditional processing method for chamfering, the edge warping defect rate is high, because edge warping will cause a large difference in the width of the warping point when chamfering

The width is an extremely important parameter index and rigid requirement for customer requirements. Generally, the width of the same side cannot exceed 40um, and the width of the front and back sides of the same position cannot exceed 100um. The width must exceed 150um, especially the warping of the entry point and the exit point, and the width must exceed 200um, which will lead to scrapping

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