| 摘要 |
PROBLEM TO BE SOLVED: To solve such a problem that a thin film transistor (TFT) fabricated based on a polycrystalline semiconductor film, obtained by performing laser annealing after introducing a metal element above an amorphous semiconductor film and performing heating treatment in the crystallization step of an amorphous semiconductor film, has very high electrical characteristics but variation may be remarkable.SOLUTION: A first polycrystalline semiconductor film, where amorphous areas are scattered in a continuous crystallization region, is obtained by introducing a metal element above an amorphous semiconductor film and performing heating treatment. The amorphous areas are confined in a predetermined range. When the first polycrystalline semiconductor film is irradiated with a laser beam in such a wavelength region that energy can be applied from the crystallization region to the amorphous areas, the amorphous areas can be crystallized without collapsing the crystallization region. When fabricating a TFT based on a second polycrystalline semiconductor film obtained via the crystallization step mentioned above, high electrical characteristics are obtained while suppressing variation. |
