Patent ID: 8263479

Claim:
A method of cutting a semiconductor substrate, the method comprising the steps of: irradiating a semiconductor substrate having a front face and a rear face and a sheet bonded thereto by way of a die-bonding resin layer with laser light, having a wavelength that enables the laser light to transmit through the semiconductor substrate, while locating a light-converging point within the semiconductor substrate, thereby forming a modified region caused by photon absorption beneath the face of the semiconductor substrate, the modified region forming a part which is to be cut; and expanding the sheet after forming the part which is to be cut, thereby cutting and separating the semiconductor substrate with the die-bonding resin layer bonded thereto into adjacent separated portions of the semiconductor substrate each having at least a portion of the die-bonding resin layer bonded thereto, forming a gap between the adjacent separated portions of the semiconductor substrate, and cutting and separating at least the semiconductor substrate along the part which is to be cut, wherein the die-bonding resin layer simultaneously begins to be separated into pieces at the same time the semiconductor substrate is separated into pieces in response to expanding of the sheet.