Method of manufacturing thin film transistor and method of manufacturing organic light emitting display having thin film transistor

A method of manufacturing a thin film transistor comprising:

• forming a gate electrode on an insulating substrate;
• forming a gate insulating layer on the gate electrode;
• forming a semiconductor layer including oxygen ions on the gate insulating layer, the semiconductor layer including a channel region, a source region, and a drain region;
• forming a passivation layer on the semiconductor layer by coating a material;
• forming a photoresist film on the passivation layer and then patterning the photoresist film to expose the source region and drain region of the semiconductor layer;
• and
• forming a source electrode and a drain electrode to contact the semiconductor layer in the source region and the drain region, respectively,
• wherein a carrier density of the semiconductor layer is 1E+17 to 1E+18/cm3.

A method of manufacturing an organic light emitting display comprising:

• forming a gate electrode on an insulating substrate;
• forming a gate insulating layer on the gate electrode;
• forming a semiconductor layer including oxygen ions on the gate insulating layer, the semiconductor layer including a channel region, a source region, and a drain region on the gate insulating layer;
• forming a passivation layer on the semiconductor layer by coating a material;
• forming a photoresist film on the passivation layer and then patterning the photoresist film to expose the source region and drain region of the semiconductor layer;
• forming a source electrode and a drain electrode to contact the semiconductor layer in the source region and the drain region, respectively;
• forming a planarization layer on the passivation layer, the source electrode, and the drain electrode, and patterning the planarization layer to expose the source electrode or the drain electrode;
• forming a first electrode on the planarization layer to contact the exposed source electrode or the drain electrode;
• forming a pixel definition layer on the planarization layer and the first electrode, and exposing the first electrode in a light emitting region thereof;
• and
• forming an organic thin film layer on the exposed first electrode and forming a second electrode on the pixel definition layer and the organic thin film layer,
• wherein a carrier density of the semiconductor layer is 1E+17 to 1E+18/cm3.