Organic light emitting diode display device including driving transistor having gate electrode under semiconductor layer
An organic light emitting diode display includes a driving transistor and a compensation transistor. The driving transistor includes a first gate electrode disposed on a substrate, a polycrystalline semiconductor layer disposed on the first gate electrode of the driving transistor and including a first electrode, a second electrode, and a channel, and a second gate electrode disposed on the polycrystalline semiconductor layer of the driving transistor. The compensation transistor includes a polycrystalline semiconductor layer including a first electrode, a second electrode, and a channel, and a gate electrode disposed on the polycrystalline semiconductor layer of the compensation transistor.
1. An organic light emitting diode display, comprising:
a substrate;
a pixel disposed on the substrate;
a scan line;
a data line;
a driving voltage line; and
an initialization voltage line,
wherein the scan line, the data line, the driving voltage line, and the initialization voltage line are connected to the pixel,
wherein the pixel comprises:
an organic light emitting element;
a first switching transistor connected to the scan line;
a driving transistor that applies a current to the organic light emitting element; and
a compensation transistor that compensates an operation of the driving transistor,
wherein the driving transistor comprises:
a first gate electrode; and
a polycrystalline semiconductor layer comprising a channel,
wherein the compensation transistor comprises:
a polycrystalline semiconductor layer comprising a channel; and
a first gate electrode disposed on the polycrystalline semiconductor layer of the compensation transistor,
wherein the first gate electrode of the driving transistor is disposed between the polycrystalline semiconductor layer of the driving transistor and the substrate.
2. The organic light emitting diode display of claim 1 , wherein the driving transistor further comprises:
a second gate electrode disposed on the polycrystalline semiconductor layer of the driving transistor.
3. The organic light emitting diode display of claim 2 , wherein the second gate electrode of the driving transistor receives a driving voltage that flows to the driving voltage line.
4. The organic light emitting diode display of claim 3 , wherein the driving transistor further comprises:
an overlapping layer disposed between the substrate and the first gate electrode of the driving transistor.
5. The organic light emitting diode display of claim 4 , wherein the driving voltage that flows to the driving voltage line is applied to the overlapping layer.
6. The organic light emitting diode display of claim 5 , further comprising:
a driving voltage application part that applies the driving voltage to the overlapping layer and the second gate electrode of the driving transistor.
7. The organic light emitting diode display of claim 1 , further comprising:
a second switching transistor,
wherein the first switching transistor is connected to the scan line and the data line, and the second switching transistor is connected to the scan line and the first gate electrode of the driving transistor.
8. The organic light emitting diode display of claim 7 , wherein the first switching transistor comprises:
a polycrystalline semiconductor layer comprising a channel; and
a first gate electrode disposed on the polycrystalline semiconductor layer of the first switching transistor.
9. The organic light emitting diode display of claim 8 , wherein the first switching transistor further comprises:
a second gate electrode disposed under the polycrystalline semiconductor layer of the first switching transistor,
wherein a driving voltage that flows to the driving voltage line is applied to the second gate electrode of the first switching transistor.
10. The organic light emitting diode display of claim 7 , wherein the first switching transistor comprises:
a gate electrode disposed on the substrate; and
a polycrystalline semiconductor layer disposed on the gate electrode of the first switching transistor and comprising a channel.
11. The organic light emitting diode display of claim 7 , wherein the second switching transistor comprises:
a polycrystalline semiconductor layer comprising a channel; and
a first gate electrode disposed on the polycrystalline semiconductor layer of the second switching transistor.
12. The organic light emitting diode display of claim 11 , wherein the second switching transistor further comprises:
a second gate electrode disposed under the polycrystalline semiconductor layer of the second switching transistor,
wherein the second gate electrode of the second switching transistor receives a driving voltage that flows to the driving voltage line.
13. The organic light emitting diode display of claim 12 , wherein the first switching transistor comprises:
a polycrystalline semiconductor layer comprising a channel; and
a first gate electrode disposed on the polycrystalline semiconductor layer of the first switching transistor.
14. The organic light emitting diode display of claim 13 , wherein the first switching transistor further comprises:
a second gate electrode disposed under the polycrystalline semiconductor layer of the first switching transistor,
wherein the second gate electrode of the first switching transistor receives the driving voltage that flows to the driving voltage line.
15. The organic light emitting diode display of claim 12 , wherein the driving transistor further comprises:
an overlapping layer disposed between the substrate and the first gate electrode of the driving transistor,
wherein the overlapping layer receives the driving voltage, and
the overlapping layer is electrically connected to the second gate electrode of the second switching transistor such that the driving voltage is applied to the second gate electrode of the second switching transistor.
16. The organic light emitting diode display of claim 15 , further comprising:
a driving voltage application part,
wherein the driving transistor further comprises a second gate electrode disposed on the polycrystalline semiconductor layer of the driving transistor, and
the driving voltage application part applies the driving voltage to the overlapping layer and the second gate electrode of the driving transistor.
17. The organic light emitting diode display of claim 7 , wherein the second switching transistor comprises:
a gate electrode disposed on the substrate; and
a polycrystalline semiconductor layer disposed on the gate electrode of the second switching transistor and comprising a channel.
18. The organic light emitting diode display of claim 1 , wherein the compensation transistor initializes the first gate electrode of the driving transistor.
19. The organic light emitting diode display of claim 18 , wherein the compensation transistor further comprises:
a second gate electrode disposed under the polycrystalline semiconductor layer of the compensation transistor,
wherein the second gate electrode of the compensation transistor receives a driving voltage that flows to the driving voltage line.
20. An organic light emitting diode display, comprising:
a substrate;
a pixel disposed on the substrate;
a scan line;
a data line;
a driving voltage line; and
an initialization voltage line,
wherein the scan line, the data line, the driving voltage line, and the initialization voltage line are connected to the pixel,
wherein the pixel comprises:
an organic light emitting element;
a first switching transistor connected to the scan line;
a driving transistor that applies a current to the organic light emitting element; and
a compensation transistor that compensates an operation of the driving transistor,
wherein the driving transistor comprises:
a first gate electrode;
a polycrystalline semiconductor layer comprising a channel; and
a second gate electrode disposed on the polycrystalline semiconductor layer of the driving transistor;
wherein the compensation transistor comprises:
a polycrystalline semiconductor layer comprising a channel; and
a first gate electrode disposed on the polycrystalline semiconductor layer of the compensation transistor,
wherein the compensation transistor does not comprise a second gate electrode disposed under the polycrystalline semiconductor layer of the compensation transistor,
wherein the first gate electrode of the driving transistor is disposed between the polycrystalline semiconductor layer of the driving transistor and the substrate.