Wafer processing method

Abstract

The present invention provides a wafer processing method capable of reliably dividing a wafer in which devices are formed by functional layers laminated on the surface of a substrate along lanes without reducing the bending strength of the devices. A wafer processing method is a method of dividing a wafer formed with a device through a functional layer laminated on the surface of a substrate along a plurality of intervals dividing the device. The wafer processing method includes: forming a scribe groove The process is to irradiate laser beams with absorptive wavelengths with respect to the functional layer from the surface side of the wafer along the spaced roads formed on the wafer, and form scribe grooves that do not reach the substrate along the spaced roads in the functional layer; modified layer formation process irradiating laser light with a wavelength that is transmissive to the substrate of the wafer from the back side of the wafer along the intervals, forming a modified layer along the intervals inside the substrate; The wafer exerts an external force to split the wafer along the lanes.

Description

technical field [0001] The present invention relates to a method for processing a wafer in which devices are formed by functional layers stacked on the surface of a substrate, and divided along a plurality of partitions dividing the devices. Background technique [0002] As is well known to those skilled in the art, in the semiconductor device manufacturing process, a plurality of IC (Integrated circuit, integrated circuit), LSI (Large Scale Integration, large-scale integrated circuits) and other devices are formed into matrix semiconductor wafers. The semiconductor wafer formed in this way divides the above-mentioned devices by dividing lines called streets, and the semiconductor wafer thus formed is divided along the streets to manufacture individual semiconductor devices. [0003] Recently, in order to improve the processing capability of semiconductor chips such as ICs and LSIs, semiconductor wafers of the following method have been put into practical use by laminating ...

AI Technical Summary

Problems solved by technology

Therefore, there is a problem that the bending strength of the device is lowered because the outer peripheral edge of the surface side of the substrate constituting the device divided along the street is melted and re-solidified by laser processing.

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