LASER BEAM MACHINING METHOD

摘要

A laser beam machining method capable of accurately cutting a workpiece along predicted cut lines, comprising the steps of forming cut start areas (8) in the workpiece (1) along the predicted cut lines (5) by reformed areas (7) formed by multiple photon absorption, and radiating laser beam (L2) having a permeability for the non-reformed areas of the workpiece (1) onto the workpiece (1) along the predicted cut lines (5) to produce cracks (24) in the workpiece (1) starting at the cut start areas (5), whereby the workpiece (1) can be accurately cut along the predicted cut lines (5) and, since chips (25) are separated from each other by extending an extension film (19) for fixing the workpiece (1) thereto, the certainty of cutting of the workpiece (1) along the predicted cut lines (5) can be further increased.