摘要 |
A workpiece including an irregularly shaped portion on a dividing line is divided along the dividing line by detecting the location of the irregularly shaped portion, applying a detecting laser beam to an area of the workpiece except for the detected location, along the dividing line to detect the height of a surface of the workpiece except for the location, applying and focusing a machining laser beam having a wavelength which permeates the workpiece within the workpiece while moving a focused spot of the machining laser beam based on the detected height of the surface of the workpiece to form a modified layer in an area of the workpiece except for at least the location of the irregularly shaped portion along the dividing line, and applying an external force to the modified layer to divide the workpiece along the dividing line. |