Patent ID: 7018749

Claim:
A crystallization apparatus comprising: a phase shift mask; and an illumination system which illuminates the phase shift mask, the crystallization apparatus irradiating a polycrystal semiconductor film or an amorphous semiconductor film with a light ray having a light intensity distribution with an inverse peak pattern that a light intensity is minimum in an area corresponding to a phase shift portion of the phase shift mask, thereby generating a crystallized semiconductor film, the crystallization apparatus further comprising an image forming optical system which has an image side numerical aperture set to a value required to generate the light intensity distribution with the inverse peak pattern and sets the polycrystal semiconductor film or the amorphous semiconductor film and the phase shift mask to an optically conjugate relationship, the phase shift mask having a boundary area which extends in a first direction across the phase shift mask, and a first area and a second area which are arranged on opposite sides of the boundary area in a second direction intersecting the first direction, and the first and second areas having a predetermined phase difference therebetween, and the boundary area having a phase distribution which varies from a phase of the first area to a phase of the second area in the second direction.