Organic light-emitting diode (oled) display and method for manufacturing the same

A method of manufacturing an organic light-emitting diode (OLED) display, comprising:

• forming a first semiconductor layer and a second semiconductor layer over a substrate;
• forming a gate insulating layer over the first and second semiconductor layers and the substrate;
• forming a first gate electrode over the gate insulating layer such that the first gate electrode is formed directly above at least a portion the first semiconductor layer;
• forming a first interlayer insulating layer over the first gate electrode and the gate insulating layer;
• forming a second gate electrode over the first interlayer insulating layer such that the second gate electrode is formed directly above at least a portion of the first gate electrode;
• forming a third gate electrode over the first interlayer insulating layer such that the third gate electrode is formed directly above at least a portion of the second semiconductor layer;
• and
• doping the first and second semiconductor layers,
• wherein the width of the second gate electrode is less than that of the first gate electrode,
• wherein the first semiconductor layer includes a first channel region, a first source region, a first drain region, and a lightly doped region between i) the first channel region and ii) the first source and drain regions,
• wherein the lightly doped region overlaps the first gate electrode and does not overlap the second gate electrode.

An organic light-emitting diode (OLED) display including a plurality of thin film transistors (TFTs), each TFT comprising:

• a substrate;
• a semiconductor layer formed over the substrate and including a first channel region, a source region, a drain region, and a lightly doped region formed between i) the first channel region and ii) the source and drain regions;
• a first gate electrode formed directly over at least a portion of the semiconductor layer;
• and
• a second gate electrode formed directly over at least a portion of the first gate electrode,
• wherein the width of the second gate electrode is less than that of the first gate electrode,
• wherein at least a portion of the lightly doped region overlaps the first gate electrode and does not overlap the second gate electrode.