Thin film transistor and organic light emitting pixel having the same

An organic light emitting pixel, comprising:

• an organic light emitting diode;
• a first thin film transistor that outputs a pixel voltage in response to a gate voltage;
• a second thin film transistor connected to the first thin film transistor and the organic light emitting diode and that is turned on in response to the pixel voltage to control a driving current flowing through the organic light emitting diode;
• and
• a capacitor connected to the first thin film transistor and the second thin film transistor to control a turn-on period of the second thin film transistor, at least one of the first thin film transistor and the second thin film transistor comprising:
• a control electrode;
• a semiconductor pattern that includes a first input area, an output area, a channel area formed between the first input area and the output area and overlapped with the control electrode to be insulated from the control electrode, and a second input area formed between and abutting the first input area and the channel area and doped with a doping concentration different from a doping concentration of the first input area;
• a first input electrode making direct contact with the first input area;
• a second input electrode making direct contact with the second input area and receiving a control voltage to control a threshold voltage;
• and
• an output electrode making direct contact with the output area.