Line beam light source, line beam irradiation device, and laser lift off method

A line beam irradiation apparatus comprising:

• a work stage;
• a line beam source for irradiating a work placed on the work stage with a line beam;
• and
• a transporting device for moving at least one of the work stage and the line beam source such that an irradiation position of the line beam on the work moves in a direction transverse to the line beam,
• wherein the line beam source includes a plurality of semiconductor laser devices and a support for supporting the plurality of semiconductor laser devices,
• each of the plurality of semiconductor laser devices includes a semiconductor multilayer stack which has a facet, the facet including an emission region from which laser light is to be emitted, the emission region having a size in a fast axis direction that is parallel to a layer stacking direction of the semiconductor multilayer stack and a size in a slow axis direction that is perpendicular to the layer stacking direction, and
• the plurality of semiconductor laser devices are arranged along a same line extending in the fast axis direction, and the laser light emitted from the emission regions of respective ones of the plurality of semiconductor laser devices diverge parallel to the same line to form the line beam.