Double gate thin-film transistor and OLED display apparatus including the same
A double gate thin-film transistor (TFT), and an organic light-emitting diode (OLED) display apparatus including the double gate TFT, includes a double gate thin-film transistor (TFT) including: a first gate electrode on a substrate; an active layer on the first gate electrode; source and drain electrodes on the active layer; a planarization layer on the substrate and the source and drain electrodes, and having an opening corresponding to the active layer; and a second gate electrode in the opening.
1. A method of manufacturing an organic light-emitting diode (OLED) display apparatus, the method comprising:
forming a first gate electrode on a substrate;
forming a gate-insulating layer on the first gate electrode;
forming the active layer on the gate-insulating layer;
forming an interlayer insulating layer on the active layer;
forming source and drain electrodes on the interlayer insulating layer;
forming a planarization layer on the source and drain electrodes;
forming a pixel electrode on the planarization layer;
forming a pixel-defining layer (PDL) on the pixel electrode and the planarization layer;
forming a first opening for exposing a portion of the planarization layer corresponding to the first gate electrode by etching the PDL and the planarization layer, and a second opening for exposing a portion of the pixel electrode, by etching the PDL; and
forming an opposite electrode facing the pixel electrode in the first opening and facing the first gate electrode in the second opening.
2. The method of claim 1 , wherein the pixel electrode is electrically connected to one of the source or drain electrodes.
3. The method of claim 1 , wherein the opposite electrode is a second gate electrode corresponding to the first gate electrode.
4. The method of claim 1 , wherein a positive voltage is configured to be applied to the first gate electrode, and a negative voltage is configured to be applied to the opposite electrode.
5. The method of claim 1 , wherein the active layer comprises an oxide semiconductor.
6. The method of claim 1 , further comprising forming a light-emitting layer in the second opening before the forming of the opposite electrode.
7. A method of manufacturing a double gate thin-film transistor (TFT), the method comprising:
forming a first gate electrode on a substrate;
forming a gate-insulating layer on the first gate electrode;
forming an active layer on the gate-insulating layer;
forming an interlayer insulating layer on the active layer;
forming source and drain electrodes on the interlayer insulating layer;
forming a planarization layer on the source and drain electrodes;
forming an opening corresponding to the first gate electrode by etching the planarization layer; and
forming a second gate electrode in the opening, wherein the second gate electrode is a cathode electrode of an organic light-emitting diode (OLED) display apparatus.
8. The method of claim 7 , wherein the active layer comprises an oxide semiconductor.
9. The method of claim 7 , wherein a positive voltage is configured to be applied to the first gate electrode, and a negative voltage is configured to be applied to the second gate electrode.
10. A method of manufacturing an organic light-emitting diode (OLED) display apparatus, the method comprising:
forming a first gate electrode on a substrate;
forming an active layer on the first gate electrode;
forming source and drain electrodes on the active layer;
forming a planarization layer on the source and drain electrodes;
forming a pixel electrode on the planarization layer and electrically connected to one of the source or drain electrodes;
etching the planarization layer in a region corresponding to the first gate electrode;
forming a light-emitting layer on the pixel electrode; and
concurrently forming an opposite electrode corresponding to the pixel electrode and a second gate electrode corresponding to the first gate electrode by depositing a conductive material layer on an entire surface of the substrate including the light-emitting layer.
11. The method of claim 10 , further comprising:
forming a pixel-defining layer (PDL) on the pixel electrode and the planarization layer; and
forming a first opening for exposing a portion of the planarization layer corresponding to the first gate electrode by etching the PDL and the planarization layer, and a second opening for exposing a portion of the pixel electrode by etching the PDL;
wherein the conductive material layer is formed in the first and the second openings.
12. The method of claim 10 , further comprising:
forming a gate-insulating layer between the first gate electrode and the active layer; and
forming an interlayer insulating layer between the active layer and at least a portion of the source and drain electrodes.