Display with Hybrid Column Spacer Structures

• US 20170293174A1
• Filed: 09/08/2016
• Published: 10/12/2017
• Est. Priority Date: 04/08/2016
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Tai, Chia Hsuan, Chen, Cheng, Yu, Da, Dorjgotov, Enkhamgalan, Choi, Sang Un, Fan Jiang, Shih-Chyuan, Cha, Tae Woon, Ham, Yeon Sik, Chen, Yuan, Ge, Zhibing, Nemati, Hossein
• Granted Patent: US 10,690,970 B2
• Time in Patent Office: Days
• CPC Class Codes: G02F 1/133357 Planarisation layers
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G02F 1/133514 Colour filters
• CPC Class Codes: G02F 1/133528 Polarisers
• CPC Class Codes: G02F 1/133711 by organic films, e.g. polymeric films
• CPC Class Codes: G02F 1/13394 spacers regularly patterned on the cell subtrate, e.g. walls, pillars G02F1/133377 takes precedence
• CPC Class Codes: G02F 1/13398 Spacer materials; Spacer properties
• CPC Class Codes: G02F 1/13439 characterised by their electrical, optical, physical properties; materials therefor; method of making
• CPC Class Codes: G02F 1/136227 Through-hole connection of the pixel electrode to the active element through an insulation layer
• CPC Class Codes: G02F 1/136286 Wiring, e.g. gate line, drain line
• CPC Class Codes: G02F 1/1368 in which the switching element is a three-electrode device G02F1/136277 takes precedence
• CPC Class Codes: G02F 1/137 characterised by the electro-optical or magneto-optical effect, e.g. field-induced phase transition, orientation effect, guest-host interaction or dynamic scattering
• CPC Class Codes: G02F 2201/123 pixel
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display

Abstract

A liquid crystal display may have main column spacers and subspacer column spacers. The column spacers may have cross shapes formed from overlapping perpendicular rectangular column spacer portions respectively located on a color filter layer and a thin-film transistor layer. The column spacers may have a hybrid configuration in which some of the rectangular portions on the thin-film transistor layer extend vertically and some extend horizontally. Column spacers may be formed from planarization layer material, may be formed from locally thickened portions of a planarization layer, and may have circular shapes.

Claims

1. A display having perpendicular first and second lateral dimensions, comprising:

a color filter layer having an inner surface and an opposing outer surface;

a thin-film transistor layer having an outer surface and having an opposing inner surface that faces the inner surface of the color filter layer;

a layer of liquid crystal material between the color filter layer and the thin-film transistor layer;

main column spacers of which has a first elongated portion on the inner surface of the thin-film transistor layer that extends along the first lateral dimension and a second elongated portion on the inner surface of the color filter layer that extends along the second lateral dimension; and

subspacers each of which has a first elongated portion on the inner surface of the thin-film transistor layer that extends along the second lateral dimension and a second elongated portion on the inner surface of the color filter layer that extends along the first lateral dimension.

2. The display defined in claim 1 wherein the thin-film transistor layer comprises a substrate layer, thin-film transistor circuitry on the substrate layer, and a planarization layer on the thin-film transistor circuitry.

3. The display defined in claim 2 further comprising contact holes in the planarization layer.

4. The display defined in claim 3 wherein the first elongated portion of each subspacer fills at least one of the contact holes.

5. The display defined in claim 3 wherein the first elongated portion of each subspacer fills two of the contact holes.

6. The display defined in claim 3 wherein the first elongated portion of each subspacer fills three of the contact holes.

7. The display defined in claim 2 wherein the first elongated portion of each of the main column spacers and the planarization layer are formed from a common polymer material.

8. The display defined in claim 7 wherein the polymer material comprises positive acrylic photoresist.

9. The display defined in claim 2 further comprising indium-tin-oxide electrodes on the planarization layer.

10. The display defined in claim 9 further comprising indium-tin-oxide structures in at least part of the contact holes.

11. The display defined in claim 1 wherein the first elongated portion of each of the main column spacers and the second elongated portion of each of the main column spacers have rectangular outlines.

12. The display defined in claim 11 wherein the first elongated portion of each of the subspacers and the second elongated portion of each of the subspacers have rectangular outlines.

13. The display defined in claim 12 wherein the first and second elongated portions of each of the subspacers do not contact each other in absence of pressure that compresses the layer of liquid crystal material between the inner surfaces.

14. The display defined in claim 1 further comprising polymer alignment layers on the inner surfaces.

15. The display defined in claim 14 wherein the thin-film transistor layer comprises a planarization layer with contact holes and wherein at least some of the contact holes are filled with a polymer other than polymer from the polymer alignment layers.

16. A display, comprising:

a color filter layer having an inner surface and an opposing outer surface;

a thin-film transistor layer having an outer surface and having an opposing inner surface that faces the inner surface of the color filter layer, wherein the thin-film transistor layer comprises a substrate layer, thin-film transistor circuitry on the substrate layer, and a planarization layer on the thin-film transistor circuitry, wherein the planarization layer has first portions and second portions, and wherein the first portions are thicker than the second portions.

a layer of liquid crystal material between the color filter layer and the thin-film transistor layer; and

column spacers that each have a color filter layer portion that is formed on the inner surface of the color filter layer and have an opposing thin-film-transistor layer portion on the thin-film transistor layer that is formed as an integral part of a respective one of the first portions.

17. The display defined in claim 16 wherein the color filter layer comprises red, blue, and green color filter elements and wherein the thin-film transistor layer has chevron-shaped electrodes.

18. The display defined in claim 17 wherein the column spacers include main column spacers that extend between the inner surfaces of the color filter layer and the thin-film transistor layer.

19. The display defined in claim 18 wherein the column spacers include subspacers each having first and second subspacer portions with respective heights and wherein the main column spacers have heights that are greater than the sum of the heights of the first and second subspacer portions of the subspacers.

20. A display, comprising:

a color filter layer having an inner surface and an opposing outer surface;

a thin-film transistor layer having an outer surface and having an opposing inner surface that faces the inner surface of the color filter layer, wherein the thin-film transistor layer comprises a substrate layer and thin-film transistor circuitry on the substrate layer;

a layer of liquid crystal material between the color filter layer and the thin-film transistor layer; and

column spacers that extend between the inner surface of the thin-film-transistor layer and the inner surface of the color filter layer and that have circular shapes.