Patent ID: 8530341

Claim:
A method of manufacturing an organic light emitting diode, comprising: forming an amorphous silicon film on a buffer layer disposed on a substrate; heat-treating the amorphous silicon film to form a microcrystalline silicon film; and scanning and irradiating a linear laser beam twice or more onto the microcrystalline silicon film to form a polysilicon film, wherein a subsequent scanning of the linear laser beam partially overlaps previous scanning of the linear laser beam in a width direction, wherein the heat-treating is performed at a temperature ranging from about 580° C. to about 750° C. for about 10 to 180 minutes, and wherein forming the polysilicon layer comprises forming a first region and a second region such that a difference in root-mean-square (RMS) surface roughness between the first region and the second region is no more than about 10%.