Environmental barrier material for organic light emitting device and method of making

• US 6,497,598 B2
• Filed: 05/02/2001
• Issued: 12/24/2002
• Est. Priority Date: 12/16/1998
• Status: Expired due to Term

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Battelle Memorial Institute
• Inventors: Affinito, John D.
• Primary Examiner(s): Ramsey, Kenneth J.
• Assistant Examiner(s): WILLIAMS, JOSEPH L
• Application Number:
  US09/847,233
• Publication Number:
  US 20010015620A1
• Time in Patent Office: 601 Days
• Field of Search: 445/24, 445/25, 445/58, 313/503, 313/504, 313/506, 313/509, 313/512, 428/690
• US Class Current: 445/24
• CPC Class Codes: H10K 2102/311 Flexible OLED
• CPC Class Codes: H10K 50/8445 multilayered coatings having a repetitive structure, e.g. having multiple organic-inorganic bilayers
• CPC Class Codes: Y02E 60/10 Energy storage using batteries

Abstract

The present invention is an environmental barrier for an OLED. The environmental barrier has a foundation and a cover. Both the foundation and the cover have a top of three layers of (a) a first polymer layer, (b) a ceramic layer, and (c) a second polymer layer. The foundation and/or the cover may have a at least one set of intermediate barrier each having (a) an intermediate polymer layer with (b) an intermediate ceramic layer thereon. In a preferred embodiment, the foundation has a substrate upon which at least a top is deposited. An OLED is constructed upon the top, opposite the substrate. The cover of at least a top then placed over the OLED. The placement may be by gluing or preferably by vacuum deposition. For use as a display, it is preferred that either the ceramic layer(s) in the foundation, cover or both is substantially transparent to the light emitted by the OLED. Each layer of the foundation and the cover is preferably vacuum deposited. Vacuum deposition includes monolayer spreading under vacuum, plasma deposition, flash evaporation and combinations thereof. It is further preferred that all layers are deposited and cured between rolls or rollers to avoid the defects that may be caused by abrasion over a roll or roller.

Claims

1. A method of making a flexible environmental barrier for an organic light emitting device, comprising the steps of:

(a) assembling a foundation by

(i) providing a substrate;

(ii) vacuum depositing a top by vacuum depositing a first polymer layer on the substrate, followed by vacuum depositing a first ceramic layer on the first polymer layer, then vacuum depositing a second polymer layer on the first ceramic layer;

(b) constructing said organic light emitting device on the second polymer layer;

(c) forming a cover by vacuum depositing a third polymer layer followed by vacuum depositing a second ceramic layer on the third polymer layer, then vacuum depositing a fourth polymer layer on the second ceramic layer; and

(d) encapsulating said organic light emitting device by placing said cover over said organic light emitting device thereby forming said flexible environmental barrier encapsulating said organic light emitting device.

2. The method as recited in claim 1, wherein said assembling further comprises:

placing at least one set of intermediate barrier between said substrate and said top, wherein each set is vacuum deposited by vacuum depositing (a) an intermediate polymer layer and vacuum depositing (b) an intermediate ceramic layer thereon.

3. The method as recited in claim 1, wherein said encapsulating further comprises:

placing at least one set of intermediate barrier between said light emitting organic device and said top, by vacuum depositing (a) an intermediate polymer layer and vacuum depositing (b) an intermediate ceramic layer thereon.

4. The method as recited in claim 1, wherein said first ceramic layer is substantially transparent.

5. The method as recited in claim 1, wherein said second ceramic layer is substantially transparent.

6. The method as recited in claim 1, wherein said placing is by laminating said cover over said organic light emitting device onto said foundation.

7. The method as recited in claim 1, wherein said placing is simultaneous with said forming wherein said forming is directly upon said organic light emitting polymer.

8. The method as recited in claim 1, wherein said substrate is a flexible substrate.

9. The method as recited in claim 8, wherein said flexible substrate is removed from said foundation.

10. The method as recited in claim 1, wherein said first ceramic layer is selected from the group consisting of metal oxide, metal nitride, metal carbide, metal oxynitride and combinations thereof.

11. The method as recited in claim 10, wherein said metal oxide is selected from the group consisting of silica, alumina, titania, indium oxide, tin oxide, indium tin oxide and combinations thereof.

12. The method as recited in claim 10, wherein said metal nitride is selected from the group consisting of aluminum nitride, silicon nitride and combinations thereof.

13. The method as recited in claim 1, wherein said foundation includes a flexible substrate selected from the group consisting of polymer, metal, paper, fabric and combinations thereof.

14. The method as recited in claim 1, wherein said first polymer, second polymer, third polymer, fourth polymer, or combinations thereof is selected from the group consisting of acrylic, methacrylic, polyester or polyethyleneterephthalate (PET), polyethylene, polypropylene, and combinations thereof.

15. The method as recited in claim 1, wherein said polymer is selected from the group consisting of acrylic, methacrylic, polyester or polyethyleneterephthalate (PET), polyethylene, polypropylene, and combinations thereof.

16. The method as recited in claim 1, wherein said substrate is a rigid substrate that is removed from the foundation.

17. A method of making an environmental barrier for an organic light emitting device, comprising the steps of:

(a) constructing a foundation by

(i) vacuum depositing at least one intermediate barrier on a substrate each intermediate barrier having (a) a first intermediate polymer layer with (b) a first intermediate ceramic layer thereon onto the substrate;

(ii) vacuum depositing a top of a first polymer layer on the substrate, a first ceramic layer on the first polymer layer, and a second top polymer layer on the first ceramic layer;

(b) constructing said organic light emitting device on the second top polymer layer of the top; and

(c) constructing a cover by

(i) vacuum depositing at least one intermediate barrier on said organic light emitting device, each intermediate barrier having (a) a second intermediate polymer layer with (b) a second intermediate ceramic layer thereon; and

(ii) vacuum depositing a first polymer layer on said at least one intermediate barrier with a second ceramic layer thereon and a second cover polymer layer on said second ceramic layer.