Patent attributes
A crystallization apparatus of the present invention irradiates a non-single-crystal semiconductor film with a luminous flux having a predetermined light intensity distribution to crystallize the film, and comprises a phase modulation device comprising a plurality of unit areas which are arranged in a certain period and which mutually have substantially the same pattern, and an optical image forming system disposed between the phase modulation device and the non-single-crystal semiconductor film. The unit area of the phase modulation device has a reference face having a certain phase, a first area disposed in the vicinity of a center of each unit area and having a first phase difference with respect to the reference face, and a second area disposed in the vicinity of the first area and having substantially the same phase difference as that of the first phase difference with respect to the reference face.