Pixel and display device having the same
A display device includes pixels at least one of which includes a light emitting element connected between a first power source and a second power source, a first transistor connected between the first power source and the light emitting element and controlling a driving current flowing through the light emitting element in response to a voltage of a first node, a switching transistor connected to the first node and including and active layer that includes first and second conductive regions spaced apart from each other, first and second channel regions disposed between the first and second conductive regions, and a common conductive region disposed between the first and second channel regions, and a conductive pattern overlapping the active layer to face the common conductive region.
1. A display device comprising:
a substrate;
a pixel disposed on and above a main surface of the substrate and in a display area, the pixel comprising:
a light emitting element, the light emitting element being electrically connected between a first power source and a second power source;
a first transistor electrically connected between the first power source and the light emitting element and controlling a driving current flowing through the light emitting element in response to a voltage of a first node;
a switching transistor electrically connected to the first node and including an active layer, the active layer comprising:
first and second conductive regions spaced apart from each other;
a first channel region and a second channel region spaced apart from each other and disposed between the first and second conductive regions; and
a common conductive region disposed between the first and second channel regions; a conductive pattern that overlaps a center of the common conductive region of the active layer in plan view, the center being a plane within the common conductive region that is equal distant between a first boundary between the conductive pattern and the first channel region and a second boundary between the conductive pattern and the second channel region, plan view being from a direction perpendicular to the main surface of the substrate;
a first gate electrode overlapping the first channel region, and a second gate electrode overlapping the second channel region, the second gate electrode not overlapping the first gate electrode in plan view; and
the conductive pattern does not overlap both of the first and second channel regions.
2. The display device according to claim 1 , wherein the conductive pattern is disposed under the active layer to overlap the common conductive region.
3. The display device according to claim 1 , wherein the conductive pattern is disposed not to overlap the first and second conductive regions.
4. The display device according to claim 1 , wherein the conductive pattern is disposed not to overlap at least one of the first and second channel regions.
5. The display device according to claim 1 , wherein the switching transistor comprises a plurality of sub transistors including a first sub transistor and a second sub transistor electrically connected in series with each other.
6. The display device according to claim 5 , wherein
the first sub transistor includes the first conductive region, the first channel region, the common conductive region, and a first gate electrode overlapping the first channel region, and
the second sub transistor includes the second conductive region, the second channel region, the common conductive region, and a second gate electrode overlapping the second channel region and electrically connected to the first gate electrode.
7. The display device according to claim 5 , wherein the switching transistor comprises at least three sub transistors electrically connected in series with each other.
8. The display device according to claim 7 , wherein
the active layer includes at least two common conductive regions disposed between active layers of the at least three sub transistors, and
the pixel includes at least two conductive patterns respectively overlapping the at least two common conductive regions and spaced apart from each other.
9. The display device according to claim 1 , wherein the conductive pattern has a substantially symmetrical shape with respect to the common conductive region on a line connecting the first and second conductive regions.
10. The display device according to claim 1 , wherein the conductive pattern is electrically isolated.
11. The display device according to claim 1 , wherein the conductive pattern is electrically connected to a gate electrode of the switching transistor.
12. The display device according to claim 1 , wherein the conductive pattern is electrically connected to a source electrode of the switching transistor.
13. The display device according to claim 1 , wherein the conductive pattern is electrically connected to a power source.
14. The display device according to claim 1 , wherein the switching transistor comprises at least one of:
a second transistor electrically connected between a first electrode of the first transistor and a data line and including a gate electrode electrically connected to a scan line;
a third transistor electrically connected between a second electrode of the first transistor and the first node and including a gate electrode connected to the scan line; and
a fourth transistor electrically connected between the first node and an initialization power source and including a gate electrode electrically connected to a first control line.
15. The display device according to claim 14 , wherein
the third transistor includes the common conductive region, and
the conductive pattern is disposed under the active layer of the third transistor to overlap the common conductive region.
16. The display device according to claim 14 , wherein
the fourth transistor includes the common conductive region, and
the conductive pattern is disposed under the active layer of the fourth transistor to overlap the common conductive region.
17. The display device according to claim 1 , wherein
the pixel includes a plurality of switching transistors,
a predetermined number of the switching transistors are configured of multi-structure transistors each including the first and second channel regions and the common conductive region, and
the conductive pattern is disposed under the common conductive region of each of the multi-structure transistors.
18. A pixel comprising:
a substrate;
a light emitting element disposed on and above a main surface of the substrate and electrically connected between a first power source and a second power source;
a first transistor electrically connected between the first power source and the light emitting element and controlling a driving current flowing through the light emitting element in response to a voltage of a first node;
a switching transistor electrically connected to the first node, and including an active layer, the active layer comprising:
first and second conductive regions spaced apart from each other;
a first channel region and a second channel region spaced apart from each other and disposed between the first and second conductive regions; and
a common conductive region disposed between the first and second channel regions;
a conductive pattern that overlaps a center of the common conductive region of the active layer in plan view, the center being a plane within the common conductive region that is equal distant between a first boundary between the conductive pattern and the first channel region and a second boundary between the conductive pattern and the second channel region, plan view being from a direction perpendicular to the main surface of the substrate;
a first gate electrode overlapping the first channel region, and a second gate electrode overlapping the second channel region, the second gate electrode not overlapping the first gate electrode in plan view; and
the conductive pattern does not overlap both of the first and second channel regions.
19. The pixel according to claim 18 , wherein the conductive pattern is disposed under the active layer to be electrically isolated.
20. The pixel according to claim 18 , wherein the conductive pattern is electrically connected to a gate or source electrode of the switching transistor or a power source.