Patent ID: 8017507

Claim:
The method of manufacturing a polycrystalline semiconductor thin film, comprising: a semiconductor film forming step in which a nonmonocrystalline semiconductor thin film including a large heat capacity part having a large heat capacity and a small heat capacity part having a small heat capacity is formed on a substrate; and an annealing step in which a laser beam of an energy density with which the small heat capacity part melts completely but the large heat capacity part does not melt completely is irradiated to the non-monocrystalline semiconductor thin film, wherein in the laser annealing step, the laser beam is a pulse laser beam of a spot diameter processed to be in a linear shape having a short axis and a long axis, and the laser beam is irradiated while being moved sequentially in a short axial direction with a moving distance not more than a grain diameter of a seed crystal of the non-single crystalline semiconductor thin film in the short axial direction.