Liquid crystal display device and method of manufacturing liquid crystal display device

• US 8,384,860 B2
• Filed: 05/29/2008
• Issued: 02/26/2013
• Est. Priority Date: 06/26/2007
• Status: Expired due to Fees

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Kikuchi, Tetsuo, Kitagawa, Hideki, Imai, Hajime, Hara, Yoshihito, Imade, Mitsunori, Shimada, Junya
• Primary Examiner(s): NGUYEN, THANH NHAN P
• Application Number:
  US12/666,461
• Publication Number:
  US 20100182527A1
• Time in Patent Office: 1,734 Days
• Field of Search: None
• US Class Current: 349/113
• CPC Class Codes: G02F 1/133553 Reflecting elements associated to illuminating devices G02F1/133605
• CPC Class Codes: G02F 1/133555 Transflectors
• CPC Class Codes: G02F 1/13439 characterised by their electrical, optical, physical properties; materials therefor; method of making
• CPC Class Codes: G02F 1/136286 Wiring, e.g. gate line, drain line
• CPC Class Codes: G02F 2203/03 scattering

Abstract

A liquid crystal display device has a plurality of pixels and a reflection section for reflecting incident light toward a display surface. The reflection section includes a metal layer having a plurality of apertures, and a reflective layer formed on the metal layer with an insulating layer interposed therebetween. A surface of the reflective layer includes a plurality of recesses or protrusions formed in accordance with a cross-sectional shape of the metal layer.

Claims

1. A liquid crystal display device having a plurality of pixels, and comprising,

in each of the plurality of pixels, a reflection section for reflecting incident light toward a display surface, wherein,

the reflection section includes a metal layer having a plurality of apertures, and a reflective layer formed on the metal layer with an insulating layer interposed therebetween;

a surface of the reflective layer includes a plurality of recesses or protrusions formed in accordance with a cross-sectional shape of the metal layer;

regarding distance between two adjacent apertures among the plurality of apertures of the metal layer, a shortest distance is no less than 0.3 μ

m and no more than 3.0 μ

m; and

wherein the metal layer includes a plurality of main portions and a linking portion connecting the plurality of main portions, the linking portion has a width which is narrower than a width of each of a first main portion and a second main portion which are connected by the linking portion, and the linking portion has a width of no less than 0.3 μ

m and no more than 3.0 μ

m.

2. The liquid crystal display device of claim 1, wherein, of a narrow-width portion where the distance between two adjacent apertures among the plurality of apertures is no less than 0.3 μ

m and no more than 3.0 μ

m, a portion having a width of d (where d is any arbitrary value from 0.3 to 3.0) μ

m or less has a length which is d μ

m or less.

3. The liquid crystal display device of claim 1, wherein, of the linking portion, a length of a portion having a width of d (where d is any arbitrary value from 0.3 to 3.0) μ

m or less is d μ

m or less, the length being taken along a direction which is perpendicular to the width direction.

4. The liquid crystal display device of claim 3, wherein the width of the first main portion and the second main portion is equal to or greater than 1.4 times the width of the linking portion.

5. The liquid crystal display device of claim 1, wherein, as viewed from a substrate normal direction, each of the first main portion and the second main portion has a substantially square shape;

the linking portion links corner portions of the first main portion and the second main portion; and

sides of the first main portion and the second main portion which are in contact with the linking portion have a length of no less than 1.0 μ

m and no more than 10.0 μ

m.

6. The liquid crystal display device of claim 1, wherein,

a pair of electrodes for forming a storage capacitor are formed in each of the plurality of pixels;

and

the metal layer constitutes one of the pair of electrodes.

7. The liquid crystal display device of claim 6, wherein,

a transistor is formed in each of the plurality of pixels;

the reflective layer is electrically connected to a source electrode or a drain electrode of the transistor; and

the pair of electrodes are constituted by the metal layer and the reflective layer.

8. The liquid crystal display device of claim 1, wherein the surface of the reflective layer includes a plurality of recesses formed in accordance with a cross-sectional shape of the metal layer, and, regarding distance between two adjacent recesses among the plurality of recesses, a shortest distance is no less than 0.3 μ

m and no more than 3.0 μ

m.

9. The liquid crystal display device of claim 1, wherein,

a transistor is formed in each of the plurality of pixels;

and

the metal layer is made of a same material as a gate electrode of the transistor, and the reflective layer is made of a same material as a source electrode or a drain electrode of the transistor.

10. The liquid crystal display device having a plurality of pixels, and comprising,

in each of the plurality of pixels, a reflection section for reflecting incident light toward a display surface, wherein,

the reflection section includes a metal layer having a plurality of apertures, and a reflective layer formed on the metal layer with an insulating layer interposed therebetween;

a surface of the reflective layer includes a plurality of recesses or protrusions formed in accordance with a cross-sectional shape of the metal layer;

regarding distance between two adjacent apertures among the plurality of apertures of the metal layer, a shortest distance is no less than 0.3 μ

m and no more than 3.0 μ

m; and

wherein, a semiconductor layer having a recess or aperture is formed between the insulating layer and the reflective layer in the reflection section; and

the surface of the reflective layer has a recess or protrusion formed in accordance with a cross-sectional shape of the semiconductor layer.

11. The liquid crystal display device of claim 10, wherein a side face of the recess or protrusion formed on the surface of the reflective layer has a level difference which is formed in accordance with a cross-sectional shape of the metal layer and the semiconductor layer.

12. The liquid crystal display device having a plurality of pixels, and comprising,

in each of the plurality of pixels, a reflection section for reflecting incident light toward a display surface, wherein,

the reflection section includes a metal layer having a plurality of apertures, and a reflective layer formed on the metal layer with an insulating layer interposed therebetween;

a surface of the reflective layer includes a plurality of recesses or protrusions formed in accordance with a cross-sectional shape of the metal layer;

.

regarding distance between two adjacent apertures among the plurality of apertures of the metal layer, a shortest distance is no less than 0.0 μ

m and no more than 3.0 μ

m; and

further comprising;

a liquid crystal layer, an interlayer insulating layer and a pixel electrode;

wherein the pixel electrode wherein the pixel electrode interposed between the liquid crystal layer and the reflective layer, wherein a surface of the pixel electrode facing the liquid crystal layer is formed flat without conforming to a shape of the recess or protrusion of the reflective layer.

13. A production method for a liquid crystal display device having a plurality of pixels and including, in each of the plurality of pixels, a reflection section for reflecting incident light toward a display surface, the production method comprising the steps of:

forming a metal film on a substrate;

forming a resist layer on the metal film;

removing a portion of the resist layer;

performing an etching via the resist layer, thereby patterning the metal film to form a metal layer; and

forming a reflective layer on the metal layer, wherein,

in the step of forming the metal layer, the metal layer is formed so that a plurality of apertures are formed in the metal layer in the reflection section, and regarding distance between two adjoining apertures among the plurality of apertures, a shortest distance is no less than 0.3 μ

m and no more than 3.0 μ

m; and

in the step of forming the metal layer, the metal layer is formed so that the metal layer in the reflection section includes a plurality of main portions and a linking portion connecting the plurality of main portions, and that a minimum value of width of the linking portion is no less than 0.3 μ

m and no more than 3.0 μ

m.

14. The production method of claim 13, wherein, in the step of forming the reflective layer, a plurality of recesses or protrusions are formed on a surface of the reflective layer in accordance with a cross-sectional shape of the metal layer.

15. The production method of claim 13, wherein,

a transistor is formed in each of the plurality of pixels;

a gate electrode of the transistor is formed in the step of forming the metal layer; and

in the step of forming the reflective layer, a source electrode and a drain electrode of the transistor are formed.

16. The production method for a liquid crystal display device having a plurality of pixels and including, in each of the plurality of pixels, a reflection section for reflecting incident light toward a display surface, the production method comprising the step of:

forming a metal film on a substrate;

forming a resist layer on the metal film;

removing a portion of the resist layer;

performing an etching via the resist layer, thereby patterning the metal film to form a metal layer; and

forming a reflective layer on the metal layer, wherein,

in the step of forming the metal layer, the metal layer is formed so that a plurality of apertures are formed in the metal layer in the reflection section, and regarding distance between two adjacent apertures among the plurality of apertures, a shortest distance is no less than 0.3 μ

m and no more than 3.0 μ

m; and

wherein, in the step of removing a portion of the resist layer, a plurality of apertures are formed in the resist layer as the resist layer is removed; and

regarding distance between two adjacent apertures among the plurality of apertures in the resist layer, a shortest distance is no less than 0.3 μ

m and no more than 3.0 μ

m.

17. The production method for a liquid crystal display device having a plurality of pixels and including, in each of the plurality of pixels, a reflection section of reflecting incident light toward a display surface the production method comprising the steps of:

forming a metal film on a substrate;

forming a resist layer on the metal film;

removing a portion of the resist layer;

performing an etching via the resist layer, thereby patterning the metal film to form a metal layer; and

forming a reflective layer on the metal layer, wherein,

in the step of forming the metal layer, the metal layer is formed so that a plurality of apertures are formed in the metal layer in the reflection section, and regarding distance between two adjacent apertures among the plurality of apertures, a shortest distance is no less than 0.3 μ

m and no more than 3.0 μ

m; and

forming a semiconductor layer between an insulating layer and the reflective layer in the reflection section, the semiconductor layer having a recess or aperture, wherein,

in the step of forming the reflective layer, a recess or protrusion is formed on a surface of the reflective layer in accordance with a cross-sectional shape of the semiconductor layer.