CUTTING METHOD

• Main Author: FUKUMITSU KENJI
• Format: Patent
• Language: English
• Published: 11.10.2012
• Subjects: BASIC ELECTRIC ELEMENTS; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; ELECTRIC SOLID STATE DEVICES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR; PERFORMING OPERATIONS; SEMICONDUCTOR DEVICES; SOLDERING OR UNSOLDERING; TRANSPORTING; WELDING; WORKING BY LASER BEAM; WORKING CEMENT, CLAY, OR STONE; WORKING STONE OR STONE-LIKE MATERIALS

PROBLEM TO BE SOLVED: To provide a cutting method which can easily cut a silicon wafer.SOLUTION: Pulse laser light is emitted on condition that the peak power density of a focus point is not lower than 1×10(W/cm) by focusing the focus pint into the silicon wafer 2a, a melt treatment region 211a is formed in the silicon wafer 2a along a cut-scheduled line by relatively moving the pulse laser light along the cut-scheduled line, and a plurality of fine hollows 211b are formed at a side opposite to the incident side of the pulse laser light with the melt treatment region 211a which is the inside of the silicon wafer 2a sandwiched therebetween so as to be separated from one another along the cut-scheduled line. At this time, a pulse pitch of the pulse laser light is 2.00 μm to 7.00 μm. Then, cracks are generated with a reforming region 211 formed of the melt treatment region 211a and the fine hollows 211b as a starting point, and the silicon wafer 2a is cut along the cut-scheduled line.