The present invention discloses the semiconductor device having the substrate that reflects the laser beam on a surface; that absorbs the laser beam therein; or that partially reflects the laser beam on the surface and partially absorbs the laser beam in the laser annealing. Moreover, the substrate has a poly-crystalline semiconductor film having a large grain size. The present invention suppresses the effect due to the reflected light from a rear surface of the substrate and therefore the uniform laser annealing can be performed.