Substrate dividing method

摘要

A substrate dividing method which can thin and divide a substrate while preventing chipping, and cracking from occurring. This substrate dividing method comprises the steps of irradiating a semiconductor substrate 1 having a front face 3 formed with functional devices 19 with laser light while positioning a light-converging point within the substrate, so as to form a modified region including a molten processed region due to multiphoton absorption within the semiconductor substrate 1, and causing the modified region including the molten processed region to form a starting point region for cutting; and grinding a rear face 21 of the semiconductor substrate 1 after the step of forming the starting point region for cutting such that the semiconductor substrate 1 attains a predetermined thickness.

主权项

1. A semiconductor chip manufacturing method, wherein a semiconductor substrate having a plurality of circuit devices formed in matrix on a front face of the semiconductor substrate is divided into the circuit devices to obtain semiconductor chips, the manufacturing method comprising the steps of:
irradiating a laser light incident face of a substrate, the substrate comprising semiconductor material and having a surface formed with at least one semiconductor device, with laser light while positioning a light-converging point within the substrate, thereby forming a molten processed region embedded within the substrate along each line of a plurality of cutting lines arranged in a grid with respect to the substrate, the substrate having a front face and a rear face through the substrate, the front face of the substrate being formed with at least one functional device, the forming of each molten processed region resulting in the forming of a starting point region configured for cutting the substrate, and each molten processed region being located inside the substrate at a predetermined distance from the laser light incident face of the substrate; and grinding the rear face of the substrate after the forming of the starting point regions, thereby removing from the substrate at least a portion of the molten processed regions that were formed in the substrate; wherein a fracture generated in a thickness direction of the substrate from each starting point region reaches at least the front face of the substrate, thereby providing at least one semiconductor chip.