| 摘要 |
In a laser irradiation system, since a heavy scanning stage moves at a high speed, vibration is caused. When the vibration transmits to a vibration isolator where an optical system that forms a beam spot and a system are mounted, a laser irradiation track formed on a substrate, which is not linear any more, is undulating in a reflection of the vibration. It is one of objects of the present invention to suppress the undulation of the irradiation tracks due to such vibration. A light-shielding film 122 is provided over a semiconductor film 123 that is a surface to be irradiated. When the light-shielding film 122 is provided, a portion of the incident beam 121, which has a low energy density, is shielded compellingly. As described above, providing the light-shielding film 122 makes it possible to enlarge a grain size in the semiconductor film without forming the state similar to the crystals formed in the case of performing laser crystallization with excimer laser. It is preferable that the light-shielding film 122 is as thin as possible in order to minimize an effect of diffraction.
|
