Patent ID: 7772523
Filing Date: 2010-08-10
Classification: B23K,H01L

Abstract:
1. A laser irradiation apparatus comprising: a first laser oscillator; a second laser oscillator; a slit for blocking an end portion of a first laser beam emitted from the first laser oscillator; a condensing lens; means for delivering a second laser beam emitted from the second laser oscillator so as to cover a range irradiated with the first laser beam on an irradiation surface; means for moving the irradiation surface in a first direction relative to the first laser beam and the second laser beam; and means for moving the irradiation surface in a second direction relative to the first laser beam and the second laser beam, wherein the first laser oscillator and the second laser oscillator are pulsed lasers having a repetition rate of 10 MHz or more, wherein the first laser beam is a harmonic and the second laser beam is a fundamental wave, and wherein a laser spot of the second laser beam covers the whole beam spot of the first laser beam on the irradiation surface.