LASER IRRADIATION METHOD, AND SEMICONDUCTOR DEVICE FORMATION METHOD USING THE SAME

摘要

PROBLEM TO BE SOLVED: To provide a laser irradiation method that irradiates a uniform laser beam to an irradiated object even if the irradiated object has variable thicknesses in it. SOLUTION: When irradiating a laser beam to an irradiated object that has variable thicknesses, the laser beam is irradiated while the distance between a lens that condenses the laser beam to the irradiated object's surface and the irradiated object is kept constant by use of an autofocusing mechanism. In particular, when the irradiated object is irradiated with the laser beam while the irradiated object is relatively moved to a first and a second direction of the beam spot formed on its surface, the distance between the lens and the irradiated object is controlled by the autofocusing mechanism before moving it either to the first direction or the second one. COPYRIGHT: (C)2006,JPO&NCIPI