Patent ID: 6884699

Claim:
A process for making a polycrystalline silicon film comprising: forming an amorphous silicon film having a first region and a second region that partially overlaps the first region, on a substrate; condensing a laser beam having a wavelength not shorter than 390 nm and not loner than 640 nm to form a linear laser beam; forming a first polycrystalline portion by scanning the first region of the amorphous silicon film with the linear laser beam in a single scan direction so that the first polycrystalline portion extends in the scan direction; and forming a second polycrystalline portion that partially overlaps the first polycrystalline portion by scanning the second region of the amorphous silicon film and the part of the first region that overlaps the second region with the linear laser beam so that the second polycrystalline portion extends in the scan direction and is substantially parallel to the first polycrystalline portion.