Patent ID: 7772519
Filing Date: 2010-08-10
Classification: B23K,G02B

Abstract:
1. A method for manufacturing a semiconductor device comprising: forming a semiconductor film comprising silicon over a substrate; emitting a laser beam from a laser; splitting the laser beam into first and second laser beams by using first parabolic mirror and second parabolic mirror, wherein a focal position of the first parabolic mirror is in front of an irradiation surface, and a focal position of the second parabolic mirror is in the rear of the irradiation surface, wherein end portions of the first parabolic mirror and the second parabolic mirror are spaced away from each other, and wherein a line connecting the focal positions of the first parabolic mirror and the second parabolic mirror does not vertically cross the irradiation surface; and irradiating the semiconductor film with the first and second laser beams.