Mask pattern, method of fabricating thin film transistor, and method of fabricating organic light emitting display device using the same

A method of fabricating an organic light emitting display device, comprising:

• forming amorphous silicon on a substrate;
• dividing the amorphous silicon on the substrate into rectangular silicon regions including a first silicon region, each of the silicon regions having a first width and a first length;
• radiating a laser beam on the amorphous silicon;
• crystallizing the amorphous silicon using a mask pattern comprising a plurality of N contiguous laser shot regions each having the first width and the first length, N being greater than or equal to 3, each of the laser shot regions having one or more transparent portions and zero or more non-transparent portions, no two of the laser shot regions having a same total area of respective said one or more transparent portions, the crystallizing of the amorphous silicon comprising crystallizing the first silicon region by radiating the laser beam through the mask pattern for a corresponding N laser shots on the amorphous silicon, each of the laser shots for radiating the laser beam through a respective one of the laser shot regions onto the first silicon region, the mask pattern moving width-wise by the first width or length-wise by the first length with respect to the substrate between consecutive ones of the laser shots, the crystallizing of the first silicon region yielding a plurality of regions comprising N radiated regions, each of the radiated regions being subjected to a different number of the laser shots from 1 to N;
• forming a semiconductor layer having a source region, a drain region, and a channel region of a thin film transistor (TFT);
• and
• forming a first electrode, an organic layer including at least an emission layer, and a second electrode on the TFT.