A second laser light of a continuous wave oscillation is irradiated to a region melted by a first laser light of a pulsed oscillation having a harmonic. Specifically, the first laser light has a wavelength not longer than that of visible light (830 nm, preferably not more than 780 nm). The absorption coefficient of the second laser light to a semiconductor film considerably increases because the semiconductor film is melted by the first laser light, and therefore the second laser light becomes easy to be absorbed in the semiconductor film.