Laser processing method

Abstract

For processing a workpiece (100) held by a chuck table (10) with branched pulsed laser beams, if it is assumed that branch intervals (36) at which adjacent ones of the branched pulsed laser beams are spaced from each other on a surface of the workpiece (100) are represented by L, a value calculated by dividing a processing feed speed at which the chuck table (10) is moved with respect to a condensing lens (25) by a processing feed unit (14) by the frequency of the pulsed laser beam at a processing point where the branched pulsed laser beams are applied to the workpiece (100) is represented by S, and any integer is represented by n, then the branching intervals, the processing feed speed, and the frequency of the pulsed laser beam are established to satisfy the relationship of L ≠ n × S. The most suitable drawing: FIG. 5.