Colour active matrix displays

• US 7,773,176 B2
• Filed: 05/16/2006
• Issued: 08/10/2010
• Est. Priority Date: 05/17/2005
• Status: Active Grant

• Current Assignee: Hydis Technology Company Limited (E Ink Holdings Incorporated)
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Fish, David A., Childs, Mark J., French, Ian D., Hector, Jason R.
• Primary Examiner(s): Le; Uyen-Chau N
• Assistant Examiner(s): TRAN, HOANG Q
• Application Number:
  US11/914,248
• Publication Number:
  US 20080212000A1
• Time in Patent Office: 1,547 Days
• Field of Search: 349/106
• US Class Current: 349/106
• CPC Class Codes: G02F 1/133305 Flexible substrates, e.g. plastics, organic film
• CPC Class Codes: G02F 1/133516 Methods for their manufacture, e.g. printing, electro-deposition or photolithography
• CPC Class Codes: G02F 1/133567 on the back side
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• 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 27/1266 the substrate on which the devices are formed not being the final device substrate, e.g. using a temporary substrate
• CPC Class Codes: H10K 59/38 comprising colour filters or colour changing media [CCM]

Abstract

A method of manufacturing a color active matrix display device comprises forming islands over a rigid carrier substrate, forming a plastic substrate over the rigid carrier substrate, forming an array of pixel circuits over the plastic substrate and forming a display layer over the array of pixel circuits. The rigid carrier substrate is then released from the plastic substrate and the plastic substrate then has channels defined by the islands. These are filled to define color filter portions. The formation of a plastic substrate on a rigid carrier, with the use of a subsequent lift off process, enables the circuit arrays to be made on very thin plastic sheets. The color filters can then be made on the outside of the LC cell. Depressions are formed in the plastic substrate registered to the circuit array, and these are filled in with color filter material, for example by ink jet printing.

Claims

1. A method of manufacturing a color active matrix display device, comprising:

forming islands over a rigid carrier substrate;

forming a plastic substrate over the rigid carrier substrate;

forming an array of pixel circuits over the plastic substrate;

forming a display layer over the array of pixel circuits;

releasing the rigid carrier substrate from the plastic substrate after forming the display layer, the plastic substrate having channels defined by the islands;

filling the channels to define color filter portions;

manufacturing a second substrate arrangement, wherein forming a display layer over the array of pixel circuits comprises mounting the first and second substrate arrangements with electro-optic material sandwiched therebetween, the active matrix display device thereby comprising first and second substrates with the electro-optic material sandwiched therebetween, wherein manufacturing the second substrate arrangement comprises providing a second rigid carrier substrate, and a second plastic substrate over the second rigid carrier substrate;

releasing the second rigid carrier substrate from the second plastic substrate; and

adding a polarizer to the second plastic substrate.

2. The method as claimed in claim 1, wherein filling the channels comprises printing color filters into the channels.

3. The method as claimed in claim 2, wherein the printing comprises ink jet printing.

4. The method as claimed in claim 1, wherein the rigid carrier substrate comprises a glass substrate.

5. The method as claimed in claim 1, further comprising forming a release layer between the plastic substrate and the rigid carrier substrate.

6. The method as claimed in claim 1, wherein each pixel circuit comprises at least a thin film transistor.

7. The method as claimed in claim 6, wherein each thin film transistor comprises an amorphous silicon TFT.

8. The method as claimed in claim 1, wherein the release is by a laser process.

9. The method as claimed in claim 1, further comprising adding a polarizer to the plastic substrate.

10. The method as claimed in claim 1, wherein the second rigid carrier substrate comprises a glass substrate.

11. The method as claimed in claim 1, further comprising a second release layer between the second plastic substrate and the second rigid carrier substrate.

12. The method as claimed in claim 1, wherein the release of the second rigid carrier substrate from the second plastic substrate is by a laser process.

13. The method as claimed in claim 1, wherein manufacturing the second substrate arrangement further comprises providing a top conductive layer.

14. The method as claimed in claim 13, wherein the top conductive layer comprises an ITO layer.

15. The method as claimed in claim 1, wherein forming the or each plastic substrate comprises applying a plastic coating to a rigid carrier substrate using a spin-on process.

16. The method as claimed in claim 1, wherein the or each plastic substrate comprises parylene.