Patent ID: 7011709

Claim:
A crystallization apparatus comprising: an illumination optical system to emit a light beam having a homogeneous intensity distribution to a non-crystallized semiconductor film, so that the non-crystallized semiconductor film is irradiated with the light beam to crystallize the non-crystallized semiconductor film, the crystallization apparatus further comprising: an optical conversion element which converts the light beam having the homogeneous intensity distribution to a light beam having a periodical upward concave intensity distribution; and a phase shift mask which passes the light beam, gives a phase difference between parts of the light beam, and converts the light beam having the homogeneous intensity distribution into a light beam having a periodical intensity distribution of an inverse peak type, the phase shift mask having a phase shift portion to determine a position where the intensity distribution of the inverse peak type is minimized, the optical conversion element being positioned on a light path between the illumination optical system and non-crystallized semiconductor film, the phase shift mask being positioned on the light path between the optical conversion element and non-crystallized semiconductor film, and the optical conversion element and phase shift mask being positioned so that a minimum position of the upward concave intensity distribution is disposed opposite to the phase shift portion, and the light beam which is converted by the optical conversion element and phase shift mask and with which the non-crystallized semiconductor film is irradiated having the intensity distribution including an inverse peak portion inside an upward concave portion.