Organic light emitting diode display and manufacturing method thereof

• US 8,040,298 B2
• Filed: 01/10/2007
• Issued: 10/18/2011
• Est. Priority Date: 01/10/2006
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Choi, Joon-Hoo
• Primary Examiner(s): Eisen; Alexander
• Assistant Examiner(s): YEUNG, MATTHEW M
• Application Number:
  US11/621,723
• Publication Number:
  US 20070159433A1
• Time in Patent Office: 1,742 Days
• Field of Search: None
• US Class Current: 345/76
• CPC Class Codes: G09G 2300/0417 Special arrangements specific to the use of low carrier mobility technology
• CPC Class Codes: G09G 2300/0842 forming a memory circuit, e.g. a dynamic memory with one capacitor
• CPC Class Codes: G09G 2320/0214 with crosstalk due to leakage current of pixel switch in active matrix panels
• CPC Class Codes: G09G 3/3233 with pixel circuitry controlling the current through the light-emitting element
• CPC Class Codes: G09G 3/3291 in which the data driver supplies a variable data voltage for setting the current through, or the voltage across, the light-emitting elements
• CPC Class Codes: H01L 27/1214 comprising a plurality of TFTs formed on a non-semiconducting substrate, e.g. driving circuits for AMLCDs
• CPC Class Codes: H01L 27/1222 with a particular composition, shape or crystalline structure of the active layer
• CPC Class Codes: H01L 29/78678 with inverted-type structure, e.g. with bottom gate
• CPC Class Codes: H01L 29/78696 characterised by the structure of the channel, e.g. multichannel, transverse or longitudinal shape, length or width, doping structure, or the overlap or alignment between the channel and the gate, the source or the drain, or the contacting structure of the channel H01L29/78612 takes precedence; transistors having a drain offset region or a lightly doped drain [LDD] H01L29/78621
• CPC Class Codes: H10K 59/1213 the pixel elements being TFTs
• CPC Class Codes: H10K 59/131 Interconnections, e.g. wiring lines or terminals

Abstract

An OLED display according to an exemplary embodiment of the present invention includes a substrate, a gate line formed on the substrate and including a first control electrode, a data line intersecting the gate line, a switching TFT connected to the gate line and the data line, a driving TFT connected to the switching TFT, a first electrode connected to the driving TFT, a second electrode facing the first electrode, and a light emitting member formed between the first electrode and the second electrode. At least one of the switching TFT and the driving TFT includes a plurality of channels.

Claims

1. An organic light emitting diode display comprising:

a substrate;

a gate line formed on the substrate and including a first control electrode;

a secondary gate line substantially parallel to the gate line and including a secondary control electrode;

a data line intersecting the gate line;

a switching TFT connected to the gate line and the data line and having a first channel portion, a second channel portion, and a third channel portion;

a driving TFT connected to the switching TFT;

a first electrode connected to the driving TFT;

a second electrode opposite the first electrode; and

a light emitting member formed between the first electrode and the second electrode, wherein the first channel portion and the third channel portion are disposed on the secondary control electrode and the second channel portion is disposed on the first control electrode.

2. The organic light emitting diode display of claim 1, wherein the switching TFT includes a polycrystalline semiconductor.

3. The organic light emitting diode display of claim 1, wherein the driving TFT includes a polycrystalline semiconductor.

4. The organic light emitting diode display of claim 1, wherein the secondary gate line is supplied with a voltage different from that of the gate line.

5. The organic light emitting diode display of claim 4, wherein the secondary gate line is supplied with a positive voltage when the gate line is supplied with a gate-off voltage.

6. The organic light emitting diode display of claim 4, wherein the secondary gate line is floating when the gate line is supplied with a gate-off voltage.

7. The organic light emitting diode display of claim 1, wherein the secondary control electrode includes a first secondary control electrode and a second secondary control electrode, and the first control electrode is located between the first secondary control electrode and the second secondary control electrode.

8. The organic light emitting diode display of claim 7, wherein each interval between the first control electrode, and the first secondary control electrode and the second secondary control electrode, is about 4 μ

m or less.

9. The organic light emitting diode display of claim 7, wherein the plurality of channels include a first channel formed on the first secondary control electrode, a second channel formed on the first control electrode and a third channel formed on the second secondary control electrode.

10. The organic light emitting diode display of claim 9, wherein the first, second and third channels are formed on a polycrystalline semiconductor.

11. The organic light emitting diode display of claim 7, wherein the switching TFT comprises:

a first switching TFT including the first secondary control electrode, a first input electrode connected to the data line, and a first output electrode opposite the first input electrode;

a second switching TFT including the first control electrode, a second input electrode connected to the first output electrode, and a second output electrode opposite the second input electrode; and

a third switching TFT including the second secondary control electrode, a third input electrode connected to the second output electrode, and a third output electrode opposite the third input electrode.

12. The organic light emitting diode display of claim 11, wherein the first switching TFT, the second switching TFT and the third switching TFT include a polycrystalline semiconductor.

13. The organic light emitting diode display of claim 1,

wherein the secondary control electrode includes a first secondary control electrode and a second secondary control electrode,

wherein the switching TFT comprises a first semiconductor formed on the first control electrode and the secondary control electrode;

a first input electrode connected to the data line, and partially overlapping the first semiconductor;

a first input and output electrode partially overlapping the first secondary control electrode and the first control electrode, and including a portion opposite the first input electrode;

a second input and output electrode partially overlapping the second secondary control electrode, and including a portion opposite the first input and output electrode; and

a first output electrode partially overlapping the second secondary control electrode, and including a portion opposite the second input and output electrode; and

wherein the driving TFT comprises a second control electrode connected to the first output electrode;

a second semiconductor formed on the second control electrode; and

a second input electrode and a second output electrode partially overlapping the second semiconductor.

14. The organic light emitting diode display of claim 13, wherein the secondary control electrode surrounds the first control electrode, and the first control electrode is located between the first secondary control electrode and the second secondary control electrode.

15. The organic light emitting diode display of claim 14, wherein the secondary control electrode and the first control electrode are separated from each other by an interval of about 4 μ

m.

16. The organic light emitting diode display of claim 13, wherein the first input electrode, the first input and output electrode, the second input and output electrode and the first output electrode are connected to each other by the first semiconductor.

17. The organic light emitting diode display of claim 13, wherein the first semiconductor and the second semiconductor include a polycrystalline semiconductor.

18. The organic light emitting diode display of claim 13, wherein the secondary gate line is supplied with a voltage different from that of the gate line.

19. The organic light emitting diode display of claim 18, wherein the secondary gate line is supplied with a positive voltage when the gate line is supplied with a gate-off voltage.

20. The organic light emitting diode display of claim 18, wherein the secondary gate line is floating when the gate line is supplied with a gate-off voltage.