Liquid crystal display apparatus

• US 5,187,602 A
• Filed: 07/10/1991
• Issued: 02/16/1993
• Est. Priority Date: 07/12/1990
• Status: Expired due to Term

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Ikeda, Mitsushi, Murooka, Michio
• Primary Examiner(s): Sikes, William L.
• Assistant Examiner(s): MAI, HUY KIM
• Application Number:
  US07/727,865
• Time in Patent Office: 587 Days
• Field of Search: 359/58, 359/59, 359/87, 359/79, 340/784, 357/23.7, 437/101
• US Class Current: 349/39
• CPC Class Codes: G02F 1/136213 Storage capacitors associated with the pixel electrode
• CPC Class Codes: H01L 29/42384 for thin film field effect transistors, e.g. characterised by the thickness or the shape of the insulator or the dimensions, the shape or the lay-out of the conductor

Abstract

An object is to provide an active matrix type liquid crystal display apparatus with a substrate for a liquid crystal driving semiconductor device which is free from point defects, rise of production costs, and shortcircuit in a storage capacitance portion. The liquid crystal display apparatus has a substrate for a liquid crystal driving semiconductor device with a display picture element group consisting of driving semiconductor devices 15 and storage capacitances, the display picture element group being disposed on one major surface of a transparent substrate 13, wherein the storage capacitance is formed by disposing an anodic oxide film 18 between a display electrode 16 and a storage capacitance metallic line 1b made of TaN, for example, and disposed on the one major surface of the transparent substrate 13.

Claims

1. A liquid crystal display apparatus comprising:

a transparent substrate;

driving thin film transistors disposed on said transparent substrate;

display picture elements, each connected to a respective one of said driving thin film transistors; and

storage capacitance devices, each connected in parallel with a corresponding one of said display picture elements, wherein each of said storage capacitance devices includes

a storage capacitance metallic line made of a metal containing Ta and N, said storage capacitance metallic line being disposed on said transparent substrate, and

a metal oxide film formed by anodically oxidizing the surface of said storage capacitance metallic line, and

wherein the corresponding one of said display picture elements is disposed on said metal oxide film.

2. The liquid crystal display apparatus as set forth in claim 1, wherein the metal containing Ta and N, contains at least one metal selected from a group of Ta--N, Mo--Ta--N, W--Ta--N, Nb--Ta--N, Al--W--Ta--N, Al--Nb--Ta--N, Ti--W--Ta--N, Ti--Nb--Ta--N, Zr--W--Ta--N, and Zr--Nb--Ta--N.

3. The liquid crystal display apparatus as set forth in claim 1, wherein the metal containing Ta and N is Ta₀.8 N₀.2.

4. The liquid crystal display apparatus as set forth in claim 1, wherein the metal containing Ta and N is Ta₀.85 N₀.15.

5. The liquid crystal display apparatus as set froth in claim 1, wherein the metal containing Ta and N is laminated with one or more layers of Ta--N, Nb--Ta--N, Ta--Mo--N, Ta--W--N, or Ta--Nb--N.

6. The liquid crystal display apparatus as set forth in claim 1, wherein the content of N of the metal containing Ta and N, is 45 atomic % or less.

7. The liquid crystal display apparatus as set forth in claim 1, wherein a metal layer selected from a group of Al, Cu, Au, and Pt is formed as a bottom layer of the metal containing Ta and N.

8. The liquid crystal display apparatus as set forth in claim 1, wherein said metal oxide film contains a metal selected from a group of Ta, Al, Mo--Ta, W--Ta, Nb--Ta, Al--W--Ta, Ti--W--Ta, Zr--W--Ta, and Zr--Nb--Ta.

9. The liquid crystal display apparatus as set forth in claim 8, wherein said metal oxide film is Ta--O or Ta--N--O.

10. The liquid crystal display apparatus as set forth in claim 8, wherein said metal oxide film is (Ta₀.8 N₀.2)_x O_Y.

11. The liquid crystal display apparatus as set forth in claim 1, wherein the metal containing Ta and N has a dielectric constant ε

_s and a resistivity ρ

which satisfy the following relationship;

space="preserve" listing-type="equation">ε

.sub.s ×

ρ

≧

1.9×

10.sup.12.

12. A liquid crystal display apparatus comprising:

a transparent substrate;

driving thin film transistors disposed on said transparent substrate;

a plurality of display picture elements, each display picture element being connected to and driven by a corresponding driving thin film transistor; and

storage capacitance devices, each connected in parallel with a corresponding one of said plurality of display picture elements, wherein each of said storage capacitance devices includes

a storage capacitance metallic line made of a metal containing Ta and N, said storage capacitance metallic line being disposed on said transparent substrate, and

a metal oxide film formed by anodically oxidizing the surface of said storage capacitance metallic line, and

wherein the corresponding display picture element is disposed on said metal oxide film, and

wherein the metal containing Ta and N has a dielectric constant ε

_s and a resistivity ρ

which satisfy the following relationship;

space="preserve" listing-type="equation">ε

s×

ρ

>

1.9×

10.sup.12.

13. The liquid crystal display apparatus as set forth in claim 12, wherein said metal oxide of a metal contains Ta and N.

14. A liquid crystal display apparatus comprising:

a transparent substrate;

driving thin film transistors disposed on said transparent substrate;

display picture elements, each connected to a respective one of said driving thin film transistors; and

storage capacitance devices, each connected in parallel with a corresponding one of said display picture elements, wherein each of said storage capacitance devices includes

a storage capacitance metallic line made of metal layers containing Ta and N selected from Ta--N, Nb--Ta--N, Ta--Mo--N, and Ta--W--N, the metal layers laminating a Ta layer as an intermediate layer, said storage capacitance metallic line being disposed on said transparent substrate, and

a metal oxide film formed by anodically oxidizing the surface of said storage capacitance metallic line, and

wherein the corresponding one of said display picture elements is disposed on said metal oxide film.