Patent ID: 7649157
Filing Date: 2010-01-19
Classification: B23K

Abstract:
1. A chuck table for chucking a semiconductor wafer thereon in a machine for cutting semiconductor wafers along dividing lines by a laser beam, wherein said chuck table has thereon a surface with a workpiece holding area for holding a semiconductor wafer, said workpiece holding area having a shape similar to the semiconductor wafer but having a size smaller than a held semiconductor wafer; wherein said chuck table has an annular buffer groove formed in said surface to have a bottom recessed from said surface, said buffer groove surrounding the perimeter of said workpiece holding area so that the held semiconductor wafer projects outward from the periphery of said workpiece holding area to above said annular buffer groove; and wherein said buffer groove has a laser beam adsorbing member disposed on said bottom thereof, said adsorbing member having a property of absorbing the laser beam.