Patent ID: 7202144

Claim:
A method of manufacturing a semiconductor thin film which forms a substantially belt-shaped crystal crystallized by scanning laser light or a substrate onto an arbitrary region of said semiconductor thin film and performing a laser irradiation thereon, said substantially belt-shaped crystal being crystallized such that crystalline grains grow in said scanning direction, said semiconductor thin film being formed on said substrate, wherein, on XY coordinates where value x of beam size W (μm) of said laser light measured in substantially the same direction as said scanning direction is defined as X axis, and where value y of scanning velocity Vs (m/s) is defined as Y axis, said crystallization processing is performed within a region where all of the following (condition 1), (condition 2), and (condition 3) hold; (condition 1) said beam size W is larger than wavelength of said laser beam, (condition 2) said scanning velocity Vs is smaller than upper-limit of crystal growth speed, (condition 3) x×(1/y)<25 μs.