US 2004/0005744 A1Published application

Crystallization apparatus, optical member for use in crystallization apparatus, crystallization method, thin film transistor, and display

AssigneeAdvanced LCD Technologies Development Center Co., Ltd.

InventorsYukio Taniguchi, Masakiyo Matsumura, Hirotaka Yamaguchi, Mikihiko Nishitani, Susumu Tsujikawa, Yoshinobu Kimura, Masayuki Jyumonji

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Abstract

A crystallization apparatus includes an illumination optical system to illuminate a phase shift mask and which irradiates an amorphous semiconductor film with a light beam having an intensity distribution of an inverse peak type having a smallest light intensity in a point corresponding to a phase shift portion of the phase shift mask to generate a crystallized semiconductor film. A convergence/divergence element is disposed on a light path between the illumination optical system and phase shift mask. The convergence/divergence element converts the light beam supplied from the illumination optical system into a light beam having an upward concave intensity distribution in which the light intensity is lowest in the phase shift portion and in which the light intensity increases as distant from the phase shift portion to irradiate the phase shift mask.

Claims27

Dependent claims

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.

4 more elements

Dependencies are inferred from the claim text.