FINGERPRINT SENSOR, DISPLAY DEVICE, AND METHOD OF MANUFACTURING DISPLAY DEVICE

• US 20180130857A1
• Filed: 11/06/2017
• Published: 05/10/2018
• Est. Priority Date: 11/07/2016
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Inventors: LEE, Sun Hwa, JEON, Mu Kyung, KIM, II Gon
• Granted Patent: US 10,546,902 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: G06V 40/1306 non-optical, e.g. ultrasonic or capacitive sensing
• CPC Class Codes: G09G 2300/0842 forming a memory circuit, e.g. a dynamic memory with one capacitor
• CPC Class Codes: G09G 2300/0861 with additional control of the display period without amending the charge stored in a pixel memory, e.g. by means of additional select electrodes
• CPC Class Codes: G09G 2310/0262 The addressing of the pixel, in a display other than an active matrix LCD, involving the control of two or more scan electrodes or two or more data electrodes, e.g. pixel voltage dependent on signals of two data electrodes
• CPC Class Codes: G09G 2354/00 Aspects of interface with display user
• CPC Class Codes: G09G 3/2092 Details of a display terminals using a flat panel, the details relating to the control arrangement of the display terminal and to the interfaces thereto suitable for both CRT and flat panel G09G5/003; specific for a CRT G09G1/165
• CPC Class Codes: G09G 3/3233 with pixel circuitry controlling the current through the light-emitting element
• CPC Class Codes: H01L 27/14678 Contact-type imagers
• CPC Class Codes: H10K 50/844 Encapsulations
• CPC Class Codes: H10K 50/86 Arrangements for improving contrast, e.g. preventing reflection of ambient light
• CPC Class Codes: H10K 59/1201 Manufacture or treatment
• CPC Class Codes: H10K 59/122 Pixel-defining structures or layers, e.g. banks
• CPC Class Codes: H10K 59/131 Interconnections, e.g. wiring lines or terminals
• CPC Class Codes: H10K 59/40 OLEDs integrated with touch screens
• CPC Class Codes: H10K 59/65 OLEDs integrated with inorganic image sensors
• CPC Class Codes: H10K 59/873 Encapsulations

Abstract

A display device includes a display pixel and a sensor pixel. The display pixel includes a light-emitting element including a first pixel electrode. The display pixel further includes a pixel circuit electrically coupled to the light-emitting element. The sensor pixel includes a sensor electrode overlapping the first pixel electrode. The sensor pixel further includes a sensor circuit electrically coupled to the sensor electrode. The first pixel electrode includes a first opening in a region overlapping the sensor electrode.

Claims

1. A display device, comprising:

a display pixel comprising;

a light-emitting element comprising a first pixel electrode; and

a pixel circuit electrically coupled to the light-emitting element; and

a sensor pixel comprising;

a sensor electrode overlapping the first pixel electrode; and

a sensor circuit electrically coupled to the sensor electrode,

wherein the first pixel electrode comprises a first opening in a region overlapping the sensor electrode.

2. The display device according to claim 1, wherein the light-emitting element further comprises:

a second pixel electrode; and

a light-emitting layer disposed between the first pixel electrode and the second pixel electrode.

3. The display device according to claim 2, further comprising:

a pixel definition layer overlapping the pixel circuit and the sensor circuit,

wherein the pixel definition layer comprises a second opening that exposes at least a portion of the second pixel electrode.

4. The display device according to claim 3, wherein:

a portion of the first pixel electrode is disposed on the pixel definition layer; and

the pixel definition layer covers the sensor electrode.

5. The display device according to claim 4, wherein materials of the sensor electrode and the second pixel electrode are equivalent.

6. The display device according to claim 5, wherein the sensor electrode and the second pixel electrode are disposed at a same layer.

7. The display device according to claim 4, wherein, in a plan view, the sensor electrode is spaced apart from the second pixel electrode.

8. The display device according to claim 4, further comprising:

an encapsulation layer overlapping the second pixel electrode.

9. The display device according to claim 3, wherein:

a portion of the first pixel electrode is disposed on the pixel definition layer; and

the sensor electrode overlaps the first pixel electrode.

10. The display device according to claim 9, wherein the sensor electrode is electrically coupled to the sensor circuit through the first opening in the first pixel electrode.

11. The display device according to claim 10, wherein:

the sensor circuit comprises a transistor and a capacitor electrode; and

the sensor electrode is electrically coupled to the transistor in the sensor circuit through the first opening in the first pixel electrode.

12. The display device according to claim 11, wherein:

the first pixel electrode further comprises a second opening in a region overlapping the capacitor electrode of the sensor circuit; and

the sensor electrode is electrically coupled to the capacitor electrode in the sensor circuit through the second opening in the first pixel electrode.

13. The display device according to claim 9, further comprising:

an insulating layer disposed between the first pixel electrode and the sensor electrode.

14. The display device according to claim 9, wherein the sensor electrode overlaps the display pixel.

15. The display device according to claim 14, wherein the sensor electrode comprises a third opening that overlaps the light-emitting layer.

16. The display device according to claim 13, wherein the sensor electrode is electrically coupled to the sensor circuit through a contact hole in the insulating layer, the first opening in the first pixel electrode, and a contact hole in the pixel definition layer.

17. The display device according to claim 3, further comprising:

an encapsulation layer disposed on the first pixel electrode,

wherein a portion of the first pixel electrode is disposed between the pixel definition layer and the encapsulation layer, and

wherein a portion of the encapsulation layer is disposed between the sensor electrode and the first pixel electrode.

18. The display device according to claim 17, wherein the sensor electrode is electrically coupled to the sensor circuit through a contact hole in the encapsulation layer, the first opening in the first pixel electrode, and a contact hole in the pixel definition layer.

19. The display device according to claim 17, wherein the sensor electrode overlaps the display pixel.

20. The display device according to claim 19, wherein the sensor electrode comprises a second opening overlapping the light-emitting layer.

21. The display device according to claim 2, wherein:

the first pixel electrode comprises a first portion overlapping the light-emitting layer and a second portion overlapping the sensor electrode; and

the first opening is formed in the second portion of the first pixel electrode.

22. The display device according to claim 1, wherein the first opening in the first pixel electrode comprises a laser-etched surface.

23. The display device according to claim 1, wherein the pixel circuit and the sensor circuit are disposed at a same layer or disposed at different layers.

24. The display device according to claim 1, wherein:

the pixel circuit is coupled to a display scan line and a data line; and

the pixel circuit is configured to;

receive a data signal via the data line; and

supply a drive current corresponding to the data signal to the light-emitting element.

25. The display device according to claim 1, wherein:

the sensor circuit is coupled to a first sensor scan line, a second sensor scan line, and an output line;

the sensor circuit is configured to output a current through the output line; and

a magnitude of the current output to the output line varies in response to a change in capacitance between the sensor electrode and a finger overlapping the sensor electrode.

26. The display device according to claim 25, wherein the sensor circuit comprises:

a first transistor comprising a gate electrode coupled to the sensor electrode, the first transistor being configured to control the current that is output through the output line;

a second transistor comprising a gate electrode coupled to the second sensor scan line and coupled between a reference voltage line and the first transistor;

a third transistor comprising a gate electrode coupled to the first sensor scan line and coupled between the reference voltage line and the sensor electrode; and

a capacitor electrode configured to form a capacitor with the sensor electrode, the capacitor electrode being coupled to the second sensor scan line.

27. The display device according to claim 26, wherein:

the sensor circuit further comprises a fourth transistor;

the fourth transistor comprises a gate electrode coupled to a sensor control line; and

the fourth transistor is coupled between an auxiliary voltage line and the sensor electrode.

28. The display device according to claim 26, wherein:

the sensor pixel comprises a plurality of sensor pixels; and

the display device further comprises a fourth transistor coupled in common between an auxiliary voltage line and sensor electrodes of the plurality of sensor pixels.

29. A fingerprint sensor, comprising:

sensor scan lines;

output lines; and

sensor pixels coupled to the sensor scan lines and the output lines,

wherein, among the sensor pixels, a sensor pixel coupled to an i-th (“

i”

being an integer of two or more) sensor scan line and an i−

1-th sensor scan line, and a j-th (“

j”

being a natural number) output line comprises;

a first transistor coupled between the j-th output line and a first node, the first transistor comprising a gate electrode coupled to a second node;

a second transistor coupled between a reference voltage line and the first node, the second transistor comprising a gate electrode coupled to the i-th sensor scan line;

a third transistor coupled between the second node and the reference voltage line, the third transistor comprising a gate electrode coupled to the i−

1-th sensor scan line;

a first capacitor coupled between the second node and the i-th sensor scan line; and

a second capacitor coupled to the second node.

30. A method of manufacturing a display device comprising a sensor electrode, the method comprising:

forming a pixel circuit on a substrate;

forming a sensor electrode on the substrate;

forming a light-emitting element on the substrate, the light-emitting element comprising a first pixel electrode, a light-emitting layer, and a second pixel electrode; and

forming, via a laser, a first opening in a portion of the first pixel electrode, the first opening overlapping the sensor electrode,

wherein the light-emitting element is coupled to the pixel circuit.

31. The method according to claim 30, wherein the sensor electrode is disposed between the first pixel electrode and the substrate.

32. The method according to claim 30, further comprising:

forming, via a laser, a second opening in a portion of the first pixel electrode, the second opening overlapping the sensor electrode and being spaced apart from the first opening.

33. The method according to claim 32, wherein the first pixel electrode is disposed between the sensor electrode and the substrate.

34. The method according to claim 33, wherein an insulating layer is disposed between the sensor electrode and the first pixel electrode.

35. The method according to claim 34, wherein an encapsulation layer is disposed between the sensor electrode and the first pixel electrode.