| 摘要 |
PROBLEM TO BE SOLVED: To provide laser annealing which allows for high speed operation of a transistor, by growing grains in the channel region of the transistor in the direction of current flow, thereby reducing grain boundary in the channel region in the current flow direction.SOLUTION: Laser light is condensed by a micro lens array toward an amorphous silicon film, and a region corresponding to each micro lens is irradiated with the laser light thus condensed. The part thus irradiated is thereby melted and then solidified, and modified to a polysilicon film. In this case, a mask is placed so that the aperture thereof is interposed in the optical path of each micro lens, and the irradiation pattern of laser light in each irradiation part is defined by the aperture. The laser light passing through each aperture imparts such a temperature distribution that the temperature is low relatively to the irradiation part near the edge of the aperture, and high in the center of the aperture. Consequently, the current flow direction of the polysilicon film is substantially orthogonal to a part of the edge of the aperture. |
