Wafer cutting method

Abstract

The invention discloses a wafer cutting method. The wafer cutting method comprises the steps of firstly using laser for cutting along a pre-cutting mark on the front surface of a wafer, wherein the depth of the cutting channel cut by the laser exceeds the final thickness of the wafer; attaching a grinding adhesive film layer to the front surface of the wafer; and grinding the back surface of the wafer attached with the grinding adhesive film layer, grinding the wafer to a final target thickness to separate chips from each other, attaching the adhesive film layer to the back surface of the ground wafer, fixing the ground wafer on a wafer frame through the adhesive film layer, and removing the grinding adhesive film layer on the front surface of the wafer; continuously cutting along the longitudinal and transverse cutting channels between the chips by using laser to cut the adhesive film layer on the back surface of the wafer; and finally separating the adhesive film layer from the chipsin a low-temperature state. The cutting method is used for cutting an ultrathin wafer. The problem of collapse during wafer cutting is avoided. The cutting yield of the wafer is improved.

Description

technical field [0001] Embodiments of the present invention relate to the field of semiconductor manufacturing, and in particular, to a wafer cutting method. Background technique [0002] Integrated circuit chips continue to develop in the direction of high density and thinness. In order to meet the requirements, wafers need to be thinned and cut. Wafer thinning technology is the key technology of stacked chip packaging. As the number of chip stacking layers continues to increase, the thickness of the chip is gradually thinning. [0003] At present, the traditional process of wafer thinning and dicing includes process steps such as blade half-cutting, front-side film coating, back-side grinding, back-side film coating, front-side film removal, and wafer cutting. The cutting tool used in the wafer cutting process is a blade. [0004] The inventors of the present application found that in the prior art, using a mechanical blade to directly act on the surface of the wafer to c...

AI Technical Summary

Problems solved by technology

[0004] The inventors of the present application found that in the prior art, the use of a mechanical blade to directly act on the wafer surface to cut the wafer will cause stress damage inside the wafer, and the wafer is prone to chipping when the blade is cut.

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