Patent ID: 8546065

Claim:
A method of crystallizing a semiconductor layer, the method comprising: disposing a mask for crystallizing a semiconductor layer on a substrate having a semiconductor layer formed thereon, wherein the mask comprises: a plurality of first main-slit portions extending along an inclined direction with respect to a first direction, the first main-slit portions being disposed substantially parallel to one another and along a second direction substantially perpendicular to the first direction; a plurality of second main-slit portions being spaced apart from the first main-slit portions in the first direction, the second main-slit portions extending along the inclined direction with the same length as the first main-slit portions and disposed substantially parallel to one another and along the second direction; at least one upper slit portion disposed substantially parallel to and above the first main-slit portions along the second direction, the upper slit portions extending toward the second main-slit portions to be longer than the first main-slit portions; and at least one lower slit portion being disposed substantially parallel to and under the second main-slit portions along the second direction, the lower slit portions extending toward the first main-slit portions to be longer than the second main-slit portions, irradiating a first area of the substrate with a laser beam through the mask to enhance crystallinity of a portion of the semiconductor layer, by intermittently moving the mask along the first direction with respect to the substrate and irradiating the substrate through the mask at successive positions of the first area; moving the mask along the second direction with respect to the substrate; and irradiating a second area of the substrate with a laser beam through the mask to enhance crystallinity of a portion of the semiconductor layer, by intermittently moving mask along an inversion direction of the first direction and irradiating the substrate through the mask at successive positions of the second area.