FLEXIBLE ORGANIC ELECTROLUMINESCENT DEVICE AND METHOD FOR FABRICATING THE SAME

• US 20150060778A1
• Filed: 12/20/2013
• Published: 03/05/2015
• Est. Priority Date: 08/30/2013
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: KIM, Su Ho, KIM, Sang Bae, JEON, Jun Tae, LEE, Yong Sam
• Granted Patent: US 9,876,064 B2
• Time in Patent Office: Days
• US Class Current: 257/40
• CPC Class Codes: H10K 50/844 Encapsulations
• CPC Class Codes: H10K 50/868 Arrangements for polarized light emission H10K50/86 takes precedence
• CPC Class Codes: H10K 59/1201 Manufacture or treatment
• CPC Class Codes: H10K 59/124 Insulating layers formed between TFT elements and OLED elements
• CPC Class Codes: H10K 59/8722 Peripheral sealing arrangements, e.g. adhesives, sealants
• CPC Class Codes: H10K 59/873 Encapsulations
• CPC Class Codes: H10K 59/8793 Arrangements for polarized light emission H10K59/8791 takes precedence
• CPC Class Codes: H10K 77/111 Flexible substrates
• CPC Class Codes: Y02E 10/549 Organic PV cells

Abstract

Provided is a flexible organic electroluminescent device and a method for fabricating the same. In the flexible electroluminescent device, line hole patterns are formed on surfaces of a plurality of inorganic layers positioned in a pad region in which a flexible printed circuit board is connected to prevent a path of cracks caused by repeated bending and spreading of the organic electroluminescent device from spreading to the interior of the device.

Claims

1. A flexible organic electroluminescent device comprising:

a substrate having a display region including a plurality of pixel regions and a non-display region including a pad region outside the display region;

a plurality of thin film transistors (TFTs) formed in the respective pixel regions on the substrate;

an interlayer insulating layer formed in the display region including the TFTs and the non-display region, and having at least one first line hole pattern formed in the pad region of the non-display region;

a passivation layer formed on the interlayer insulating layer;

wherein the at least one line hole pattern is formed in at least one of the interlayer insulating layer and the passivation layer and located at the non-display region;

a planarization layer formed on the passivation layer;

a first electrode formed in each pixel region on the planarization layer and connected to a drain electrode of each TFT;

a pixel defining layer formed around each pixel region of the substrate including the first electrode and the non-display region;

an organic light emitting layer formed separately in each pixel region on the first electrode; and

a second electrode formed on the entire surface of the display region above the organic light emitting layer.

2. The flexible organic electroluminescent device of claim 1, further comprising:

a lower passivation layer formed on the entire surface of the substrate including the second electrode;

an organic layer formed on the lower passivation layer in the display region;

an upper passivation layer formed on the first passivation layer including the organic layer;

a barrier film disposed to face the substrate; and

a polarization plate attached to the barrier film.

3. The flexible organic electroluminescent device of claim 1, wherein the substrate is a flexible glass substrate having flexible characteristics or is made of a flexible material.

4. The flexible organic electroluminescent device of claim 1, wherein the line hole patterns overlap.

5. The flexible organic electroluminescent device of claim 1, where the line hole patterns do not overlap.

6. The flexible organic electroluminescent device of claim 1, wherein the line hole patterns are formed at a pad region of the non-display region or at the non-display region including the pad region.

7. The flexible organic electroluminescent device of claim 1, wherein at least one line hole pattern is also formed in the pad region of the gate insulating layer.

8. The flexible organic electroluminescent device of claim 6, wherein the line hole pattern of a curve type formed at the non-display region including the pad region includes a first hole pattern having curve portions surrounding a trimming line formed at edges of an upper and a lower of the pad region, and a second hole pattern extended from the first hole pattern having linear portions surrounding the display region at the non-display region located at an outside of the display region opposite to the pad region.

9. The flexible organic electroluminescent device of claim 1, wherein a polyimide layer and a plurality of buffer layers are interposed between the substrate and the plurality of thin film transistors.

10. A method for fabricating a flexible organic electroluminescent device, the method comprising:

providing a substrate in which a display region including a plurality of pixel regions and a non-display region including a pad region outside the display region are defined;

forming a plurality of thin film transistors (TFTs) in the respective pixel regions on the substrate;

forming an interlayer insulating layer on the entire surface of the substrate including the TFTs;

forming a passivation layer on the interlayer insulating layer;

forming at least one line hole pattern in at least one of the interlayer insulating layer and the passivation layer located at the non-display region;

forming a planarization layer on the passivation layer;

forming a first electrode connected to a drain electrode of each TFT in each pixel region on the planarization layer;

forming a pixel defining layer around each pixel region of the substrate including the first electrode;

forming an organic light emitting layer in each pixel region above the first electrode; and

forming a second electrode on the entire surface of the display region including the organic light emitting layer.

11. The method of claim 10, further comprising:

forming a lower passivation layer on the entire surface of the substrate including the second electrode;

forming an organic layer on the lower passivation layer in the display region;

forming an upper passivation layer on the first passivation layer including the organic layer;

forming a polarization plate together with a barrier film on the upper passivation layer;

delaminating the substrate; and

laminating a back plate to the portion from which the substrate was delaminated, after the forming of the second electrode on the entire surface of the display region including the organic light emitting layer.

12. The method of claim 10, wherein the hole patterns are formed to overlap.

13. The method of claim 10, wherein the line hole patterns are formed to not overlap.

14. The method of claim 10, wherein the line hole patterns are formed at a pad region of the non-display region or at the non-display region including the pad region.

15. The method of claim 10, wherein at least one line hole pattern is formed in the pad region of the gate insulating layer.

16. The method of claim 14, wherein the line hole pattern formed at the non-display region including the pad region includes a first hole pattern having curved portions surrounding a trimming line formed at edges of an upper and a lower of the pad region, and a second hole pattern extended from the first hole pattern having linear portions surrounding the display region at the non-display region located at an outside of the display region opposite to the pad region.

17. The method of claim 10, wherein a polyimide layer and a plurality of buffer layers are interposed between the substrate and the plurality of thin film transistors.