Reflection type liquid crystal display device and method of manufacturing the same

• US 20050088591A1
• Filed: 08/09/2002
• Published: 04/28/2005
• Est. Priority Date: 01/14/2002
• Status: Active Grant

• Current Assignee: Samsung Display Company Limited (Samsung Electronics Co. Ltd.)
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Lee, Jeong-Ho, Choi, Sang-Gun, Song, Young-Goo
• Granted Patent: US 7,230,668 B2
• Time in Patent Office: Days
• US Class Current: 349/113
• CPC Class Codes: G02F 1/13458 Terminal pads
• 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 1/136295 Materials; Compositions; Manufacture processes
• CPC Class Codes: G02F 2203/02 reflective

Abstract

Disclosed are a reflection type LCD and method of manufacturing the same. A wiring layer having a first and second metal layer (102, 104) is formed on a substrate (100) including a display region (D) and a pad region (P). Upon the substrate (100) and the wiring layer is formed a first passivation layer (155), and contacts with a wiring terminal (115) and the first metal layer (102). A second passivation layer (180) is formed on the substrate except the pad region (P). The pad contact hole (160) extends to a position under the second passivation layer (180). The second passivation layer (180) covers a region in the pad contact hole (160) where the step coverage of the pad electrode (170) is poor, thereby preventing a battery effect.

Claims

1. A reflection type liquid crystal display device comprising:

a substrate including a display region and a pad region;

a wiring layer formed on the substrate, the wiring layer being comprised of a first metal layer and a second metal layer stacked on the first layer and including a wiring layer terminal located on the pad region;

a first passivation layer formed on the substrate and the wiring layer, the first passivation layer having a pad contact hole for exposing the wiring layer terminal and the first metal layer of a portion of the wiring layer connected to the wiring layer terminal;

a pad electrode continuously formed on sidewall and bottom of the pad contact hole and on a portion of the first passivation layer, the pad electrode being comprised of a transparent conductive layer and making contact with the wiring terminal and the first metal layer of a portion of the wiring layer connected to the wiring layer terminal;

a second passivation layer formed on the substrate except the pad region; and

a reflective electrode formed on the second passivation layer of the display region;

wherein the pad contact hole is formed so as to be extended to a position under the second passivation layer located on a boundary region between the display region and the pad region.

2. The refection type liquid crystal display device as claimed in claim 1, wherein the second metal layer of the wiring layer is-comprised of aluminum (Al) or aluminum alloy.

3. The reflection type liquid crystal display device as claimed in claim 1, wherein the pad electrode is formed so as to be extended along the pad contact hole to the boundary region between the display region and the pad region.

4. A reflection type liquid crystal display device comprising:

a substrate including a display region and a pad region;

a gate wiring formed on the substrate, the gate wiring being comprised of a first metal layer and a second metal layer stacked on the first metal layer, the gate wiring including a gate line prolonged in a first direction and a gate terminal formed on the pad region so as to be connected to an end of the gate line;

a gate insulating layer formed on the gate wiring and the substrate;

a data wiring formed on the gate insulating layer, the data wiring including a data line prolonged in a second direction perpendicular to the first direction and a data terminal formed on the pad region so as to be connected to an end of the data line;

a first passivation layer formed on the data wiring and the gate insulating layer, the first passivation layer having a first pad contact hole formed through the gate insulating layer to expose the gate terminal and the first metal layer that is a portion of the gate line connected to the gate terminal;

a gate pad electrode continuously formed on the sidewall and bottom of the first pad contact hole and on a portion of the first passivation layer, the gate pad electrode being comprised of a transparent conductive layer and making contact with the gate terminal and the first metal layer of a portion of the gate line connected to the gate terminal;

a second passivation layer formed on the substrate except the pad region; and

a reflective electrode formed on the second passivation layer of the display region;

wherein the first pad contact hole extends to a position under the second passivation layer located on a boundary region between the display region and the pad region.

5. The reflection type liquid crystal display device as claimed in claim 4, wherein the second metal layer of the gate wiring is comprised of aluminum or aluminum alloy.

6. The reflection type liquid crystal display device as claimed in claim 4, wherein the gate pad electrode is formed so as to be extended along the first pad contact hole to the boundary region between the display region and the pad region.

7. The reflection type liquid crystal display device as claimed in claim 4, further comprising a data pad electrode formed from a same layer as in the gate pad electrode, the data pad electrode making contact with the data terminal via a second pad contact hole formed through the gate insulating layer and the first passivation layer over the data terminal.

8. The reflection type liquid crystal display device as claimed in claim 4, wherein the first passivation layer is comprised of an inorganic material and the second passivation layer is comprised of an organic material.

9. The reflection type liquid crystal display device as claimed in claim 4, wherein the second passivation layer has a contact hole for exposing a portion of the data line over the display region.

10. The reflection type liquid crystal display device as claimed in claim 9, wherein the reflective electrode is connected to a portion of the data line over the display region through the contact hole.

11. A method of manufacturing a reflection type liquid crystal display device comprising the steps of:

forming a wiring layer on a substrate including a display region and a pad region, the wiring layer being comprised of a first metal layer and a second metal layer stacked on the first metal layer and including a wiring layer terminal located on the pad region;

forming a first passivation layer on the substrate and the wiring layer, the first passivation layer having a pad contact hole for exposing the wiring layer terminal and the first metal layer that is a portion of the wiring layer connected to the wiring layer terminal;

continuously forming a pad electrode comprised of a transparent conductive layer on the sidewall and bottom of the pad contact hole and on a portion of the first passivation layer, the pad electrode making contact with the wiring terminal and the first metal layer of a portion of the wiring layer connected to the wiring layer terminal;

forming a second passivation layer on the substrate except the pad region; and

forming a reflective electrode on the second passivation layer in the display region.

12. The method of manufacturing a reflection type liquid crystal display device as claimed in claim 11, wherein the second metal layer of the wiring layer is comprised of aluminum or aluminum alloy.

13. The method of manufacturing a reflection type liquid crystal display device as claimed in claim 11, wherein the step of forming the first passivation layer comprises the steps of:

forming the first passivation layer on the substrate and the wiring layer;

partially etching the first passivation layer to form the pad contact hole for exposing the wiring layer terminal and the second metal layer of a portion of the wiring layer connected to the wiring layer terminal; and

etching the exposed second metal layer to expose the underlying first metal layer.

14. The method of manufacturing a reflection type liquid crystal display device as claimed in claim 11, wherein the pad electrode is formed so as to be extended along the pad contact hole to the boundary region between the display region and the pad region.

15. A method of manufacturing a reflection type liquid crystal display device comprising the steps of:

forming a gate wiring on a substrate including a display region and a pad region, the gate wiring being comprised of a first metal layer and a second metal layer stacked on the first metal layer and including a gate line prolonged in a first direction and a gate terminal formed on the pad region so as to be connected to an end of the gate line;

forming a gate insulating layer on the gate wiring and the substrate;

forming a data wiring on the gate insulating layer, the data wiring including a data line prolonged in a second direction perpendicular to the first direction and a data terminal formed on the pad region so as to be connected to an end of the data line;

forming a first passivation layer on the data wiring and the gate insulating layer, the first passivation layer having a first pad contact hole formed through the gate insulating layer to expose the gate terminal and the first metal layer that is a portion of the gate line connected to the gate terminal;

continuously forming a gate pad electrode comprised of a transparent conductive layer on the sidewall and bottom of the first pad contact hole and on a portion of the first passivation layer, the gate pad electrode making contact with the gate terminal and the first metal layer of a portion of the gate line connected to the gate terminal;

forming a second passivation layer on the substrate except the pad region; and

forming a reflective electrode on the second passivation layer in the display region.

16. The method of manufacturing a reflection type liquid crystal display device as claimed in claim 15, wherein the second metal layer of the gate wiring is comprised of aluminum or aluminum alloy.

17. The method of manufacturing a reflection type liquid crystal display device as claimed in claim 15, wherein the step of forming the first passivation layer comprises the steps of:

forming the first passivation layer on the substrate and the data wiring;

partially etching the first passivation layer and the gate insulating layer to form the first pad contact hole for exposing the gate terminal and the second metal layer of a portion of the gate line connected to the gate terminal; and

etching the exposed second metal layer to expose the underlying first metal layer.

18. The method of manufacturing a reflection type liquid crystal display device as claimed in claim 17, wherein a second pad contact hole for exposing the data terminal is formed simultaneously in the step of forming the first pad contact hole.

19. The method of manufacturing a reflection type liquid crystal display device as claimed in claim 18, wherein a data pad electrode connected to the data terminal through the second pad contact hole is formed simultaneously in the step of forming the gate pad electrode.

20. The method of manufacturing a reflection type liquid crystal display device as claimed in claim 15, wherein the gate pad electrode is formed so as to be extended along the first pad contact hole to the boundary region between the display region and the pad region.

21. The method of manufacturing a reflection type liquid crystal display device as claimed in claim 15, wherein the first passivation layer is comprised of an inorganic material and the second passivation layer is comprised of an organic material.

22. The method of manufacturing a reflection type liquid crystal display device as claimed in claim 15, wherein a contact hole exposing a portion of the data line in the display region is formed in the step of forming the second passivation layer.