LASER IRRADIATION DEVICE AND LASER IRRADIATION METHOD

摘要

PROBLEM TO BE SOLVED: To provide a laser irradiation device for forming laser beams for which energy density distribution on an irradiation plane is uniform and a laser irradiation method using it, and to provide a method for manufacturing a semiconductor device by using a semiconductor film obtained by crystallizing the semiconductor film and activating impurity elements by such a laser irradiation method. SOLUTION: The laser irradiation device is provided with a laser and two or more mirrors having a concave surface for uniformizing an energy density of the laser beam emitted from the laser in one direction. A focus position of a first mirror is present between the first mirror and the irradiation plane, and the focus position of a second mirror is not present between the second mirror and the irradiation plane but is present behind the irradiation plane. Then, by such a laser irradiation device, the semiconductor film or the like is irradiated with the laser.