Patent ID: 6890803

Claim:
A method for forming a thin film transistor (TFT) of an organic light emitting display (OLED), the method comprising the steps of: providing a substrate; depositing a first metal layer on the substrate; performing a first photo-etching process (PEP) to remove a portion of the first metal layer to form a gate of the TFT on the surface of the substrate; forming a gate insulating layer on the gate; depositing a microcrystalline silicon layer on the gate insulation layer; forming an amorphous silicon layer on the microcrystalline silicon layer; forming a doped n+ layer on the amorphous silicon layer; performing a second PEP to remove a portion of the doped n+ layer, the amorphous silicon layer, and the microcrystalline silicon layer; forming a second metal layer on the substrate; performing a third PEP to form a source and a drain of the TFT on the surface of the substrate, and simultaneously to remove a portion of the doped n+ layer to expose the amorphous silicon layer; and forming a passivation layer on the substrate.