Reflection type liquid crystal display provided with transparent pixel electrode and manufacture method thereof

• US 20050151901A1
• Filed: 03/09/2005
• Published: 07/14/2005
• Est. Priority Date: 11/18/1998
• Status: Active Grant

• Current Assignee: NLT Technologies, Ltd. (Tianma Microelectronics Company Limited)
• Original Assignee: Hironori Kikkawa, Michiaki Sakamoto
• Inventors: Sakamoto, Michiaki, Kikkawa, Hironori
• Granted Patent: US 7,046,321 B2
• Time in Patent Office: Days
• US Class Current: 349/113
• CPC Class Codes: G02F 1/133553 Reflecting elements associated to illuminating devices G02F1/133605
• CPC Class Codes: G02F 1/136222 Colour filters incorporated in the active matrix substrate
• CPC Class Codes: G02F 1/136227 Through-hole connection of the pixel electrode to the active element through an insulation layer

Abstract

In order to realize the manufacture of a reflection type liquid crystal display in the same manufacture processes as those of a transmission type liquid crystal display, a photolithography mask capable of forming both a gate electrode 22 and a reflective layer 23, and a photolithography mask capable of forming only the gate electrode 22 are prepared, and by using either one of the masks, the reflection type liquid crystal display in which both the gate electrode 22 and the reflective layer 23 are formed on a transparent insulation substrate 21, and the transmission type liquid crystal display in which only the gate electrode 22 is formed are selectively manufactured.

Claims

1-15. -15. (canceled)

16. A method of manufacturing a reflection type liquid crystal display, comprising the steps of:

forming a plurality of switching elements on one surface of a liquid crystal display panel substrate;

forming a reflective layer with the same material as a material constituting said switching element during the step of forming said plurality of switching elements;

forming an insulation layer on said reflective layer; and

forming a transparent pixel electrode on said insulation layer so as to be electrically connected to an electrode constituting said switching element.

17. The method of manufacturing the reflection type liquid crystal display according to claim 16, wherein said switching element is a thin film transistor, and said reflective layer is formed of the same material as a material of said gate electrode and formed on the same plane as a plane of said gate electrode in the step of forming the gate electrode of said thin film transistor.

18. The method of manufacturing the reflection type liquid crystal display according to claim 16, wherein said switching element is a thin film transistor, and said reflective layer is formed of the same material as a material of a source/drain electrode and formed on the same plane as a plane on which said source/drain electrode is formed in the step of forming the source/drain electrode of said thin film transistor.

19. The method of manufacturing the reflection type liquid crystal display according to claim 17, comprising the step of forming a rough portion on said substrate before the step of forming said reflective layer, so that said reflective layer is formed to cover said rough portion.

20. The method of manufacturing the reflection type liquid crystal display according to claim 18, comprising the step of forming a rough portion on said gate insulation film before the step of forming said reflective layer, so that said reflective layer is formed to cover said rough portion.

21. The method of manufacturing the reflection type liquid crystal display according to claim 16, comprising the step of forming a color filter layer on said insulation layer before the step of forming said transparent pixel electrode, so that a second insulation layer is formed on said color filter layer to form said transparent pixel electrode.

22. The method of manufacturing the reflection type liquid crystal display according to claim 16, comprising the step of forming a shielding film on said switching elements before the step of forming said transparent pixel electrode.

23. The method of manufacturing the reflection type liquid crystal display according to claim 17, comprising the steps of:

preparing a first mask for photolithography having a pattern to simultaneously form said gate electrode and the reflective layer on said substrate and a second mask for photolithography having a pattern to form only said gate electrode on said substrate; and

using either one of said first and second masks to form both said gate electrode and said reflective layer, or only said gate electrode on said substrate.

24. The method of manufacturing the reflection type liquid crystal display according to claim 18, comprising the steps of:

preparing a first mask for photolithography having a pattern to form said source/drain electrode and said reflective layer on said gate insulation film and a second mask for photolithography having a pattern to form only said source/drain electrode on said gate insulation film; and

using either one of said first and second masks to form both said source/drain electrode and said reflective layer, or said source/drain electrode on said gate insulation film.