Method for manufacturing flexible display device having an insulative overcoat and flexible display device having the same

• US 8,257,129 B2
• Filed: 03/11/2011
• Issued: 09/04/2012
• Est. Priority Date: 11/27/2006
• Status: Active Grant

• Current Assignee: LG Display Co., Ltd.
• Original Assignee: LG Display Co., Ltd.
• Inventors: Oh, Eui Yeol
• Primary Examiner(s): Green, Tracie Y
• Application Number:
  US13/046,435
• Publication Number:
  US 20110163067A1
• Time in Patent Office: 543 Days
• Field of Search: 313498-512, 445 24- 25, 257/40, 257/269
• US Class Current: 445/24
• CPC Class Codes: B29D 11/0073 Optical laminates
• CPC Class Codes: G02F 1/133305 Flexible substrates, e.g. plastics, organic film
• 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 27/1218 with a particular composition or structure of the substrate
• CPC Class Codes: H01L 27/1266 the substrate on which the devices are formed not being the final device substrate, e.g. using a temporary substrate
• CPC Class Codes: H10K 77/111 Flexible substrates
• CPC Class Codes: Y02E 10/549 Organic PV cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

A flexible display device and a method for manufacturing a flexible display are provided. The flexible display device includes a flexible substrate, a display element layer formed on the flexible substrate; an insulating protective layer covering the display element layer; and a rigid substrate. The rigid substrate has an etching selectivity at least 20 times greater than that of the insulating protective layer.

Claims

1. A manufacturing method for flexible display device, the method comprising:

forming an insulating protection layer on a first substrate;

forming a display element layer on the insulating protection layer;

attaching a flexible substrate on the display element layer;

forming an overcoat layer completely covering the display element layer and disposed between the display element layer and the flexible substrate; and

etching the first substrate to remove the first substrate using an etchant comprising a selective etching ratio of the insulating protection layer to the first substrate of less than 1/20.

2. The manufacturing method of a flexible display device according to claim 1, wherein the insulating protection layer has a thickness of 1 μ

m or less.

3. The manufacturing method of a flexible display device according to claim 1, wherein the forming the insulating protection includes depositing any one of:

a silicon layer, a silicon nitride layer, a silicon oxide layer, a metal oxide layer, and an organic layer on the first substrate.

4. The manufacturing method of a flexible display device according to claim 1, wherein the metal oxide layer includes at least one of:

chrome oxide (Cr_xO_y), tantalum oxide (TaxO_y), and Aluminum oxide (Al_xO_y).

5. The manufacturing method of a flexible display device according to claim 1, wherein the organic layer includes at least one of:

an acrylic organic material, BCB (benzo cyclobutene), PFBC (Perfluorocyclobutane), Teflon, Cytop, and Polyimide.

6. The manufacturing method of a flexible display device according claim 1, wherein the insulating protection layer comprises two or more layers.

7. The manufacturing method of a flexible display device according to claim 1, wherein the first substrate includes a glass substrate.

8. The manufacturing method of a flexible display device according to claim 7, wherein the etching the first substrate includes wet-etching the first substrate with an etchant including buffered hydrogen fluoride (HF+NH₄F:

BHF).

9. The manufacturing method of a flexible display device according to claim 8, further comprising:

before the etching the first substrate, forming a resin barrier on the first substrate on a side opposite to an insulating protection layer; and

after the etching the first substrate, removing the resin barrier.

10. The manufacturing method of a flexible display device according to claim 7, wherein the etching the first substrate includes dry-etching the first substrate with an etchant including any one of:

CF₄+O₂ and SF₆+O₂.

11. The manufacturing method of a flexible display device according to claim 1, wherein the first substrate includes a stainless substrate.

12. The manufacturing method of a flexible display device according to claim 11, wherein the etching the first substrate includes wet-etching the first substrate with an etchant including iron chloride (FeCl₂).