Light emitting device comprising an organic led array on an ultra thin substrate

• US 5,530,269 A
• Filed: 03/28/1995
• Issued: 06/25/1996
• Est. Priority Date: 11/18/1993
• Status: Expired due to Term

• Current Assignee: Global OLED Technology LLC (LG Display Co., Ltd.)
• Original Assignee: Eastman Kodak Company
• Inventors: Tang, Ching W.
• Primary Examiner(s): Hille, Rolf
• Assistant Examiner(s): TRAN, MINH LOAN
• Application Number:
  US08/412,486
• Time in Patent Office: 455 Days
• Field of Search: 257/40, 257/88, 257/91, 257/99, 313/503, 313/504, 313/506, 313/509, 313/512, 313/500, 313/505
• US Class Current: 257/88
• CPC Class Codes: B41J 2/45 using light-emitting diode [LED] or laser arrays
• CPC Class Codes: H10K 50/11 characterised by the electroluminescent [EL] layers
• CPC Class Codes: H10K 50/805 Electrodes
• CPC Class Codes: H10K 59/00 Integrated devices, or assemblies of multiple devices, comprising at least one organic light-emitting element covered by group H10K50/00
• CPC Class Codes: H10K 59/17 Passive-matrix OLED displays
• CPC Class Codes: H10K 59/8051 Anodes
• CPC Class Codes: H10K 59/8052 Cathodes
• CPC Class Codes: Y10S 148/099 LED, multicolor

Abstract

A light emitting device that comprises an organic LED array containing a plurality of light emitting pixels, the pixels each being located on a common electrically insulative transparent substrate, is characterized in that the transparent support is ultra thin, having a thickness less than the pitch of the pixels. The pixels in the LED array can be arranged in intersecting columns and rows, or they can comprise a line array. A process for forming a light emitting device on an ultra thin transparent substrate comprises the following steps: (a) releasably laminating to an ultra thin electrically insulating transparent substrate a relatively thick rigid temporary support; (b) forming the LED array on the ultra thin substrate; (c) forming on a relatively thick rigid permanent support an electrical conductor patterned in conformity with the first electrode element and the second electrode element on the ultra thin substrate; (d) forming an array of electrically conductive malleable bonding bumps on the patterned electrical conductor located on the permanent support; (e) aligning the first and second electrode elements in correct registration with the patterned electrical conductor; (f) contacting the bonding bumps on the electrical conductor with the first and second electrode elements; (g) forming a physical and electrical connection between the bonding bumps and the first and second electrode elements; and (h) delaminating the temporary support from the ultra thin transparent substrate. Additionally, a transparent and electrically insulative sealant material can be introduced into the space between the ultra thin substrate and the electrical conductor on the permanent support.

Claims

1. A light emitting device that comprises an organic LED array containing a plurality of light emitting pixels having a predetermined pitch;

a plurality of light transmissive first electrode elements located on a common electrically insulative transparent substrate, each first electrode element being laterally spaced and electrically insulated from an adjacent first electrode element;

an organic electroluminescent medium located on a supporting surface formed by the substrate and every first electrode element; and

a second electrode element located on said organic electroluminescent medium, each said pixels including a first electrode element and a second electrode element,

characterized in that said electrically insulative transparent substrate is ultra thin, having a thickness less than the pitch of said pixels.

2. A light emitting device according to claim 1 wherein said pixels are arranged in a line array.

3. A fight emitting device according to claim 1 including a permanent support and wherein a patterned electrical conductor is located on said permanent support.

4. A light emitting device according to claim 3 wherein said patterned electrical conductor is physically and electrically connected to said first electrode element and said second electrode element.

5. A light emitting device according to claim 3 wherein said patterned electrical conductor is comprised of indium tin oxide or an evaporated metal.

6. A light emitting device according to claim 5 wherein said metal is Cr or Al.

7. A light emitting device according to claim 1 wherein said electrically insulative transparent substrate has a thickness of up to about 150 μ

m.

8. A light emitting device according to claim 7 wherein said transparent substrate has a thickness of about 25 μ

m to 50 μ

m.

9. A light emitting device according to claim 1 wherein said transparent substrate is glass.