Liquid crystal display units

• US 6,522,370 B2
• Filed: 03/20/2001
• Issued: 02/18/2003
• Est. Priority Date: 11/10/2000
• Status: Expired due to Term

• Current Assignee: Panasonic Liquid Crystal Display Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Hitachi, Ltd.
• Inventors: Takahashi, Takuya, Kawamura, Tetsuya, Ishii, Masahiro, Kasai, Tsutomu, Tamura, Katsumi, Kaneko, Toshiki, Onisawa, Kenichi
• Primary Examiner(s): Sikes, William L.
• Assistant Examiner(s): CHOWDHURY, TARIFUR RASHID
• Application Number:
  US09/811,553
• Publication Number:
  US 20020057394A1
• Time in Patent Office: 700 Days
• US Class Current: 349/43
• CPC Class Codes: G02F 1/136286 Wiring, e.g. gate line, drain line
• CPC Class Codes: G02F 1/13629 Multilayer wirings
• CPC Class Codes: G02F 1/136295 Materials; Compositions; Manufacture processes

Abstract

A liquid crystal display unit is used that has data lines made of a molybdenum-alloyed film having a chromium content from 2 wt. % or more, but up to 5 wt. %, or a molybdenum-alloyed film lamination (Mo—Cr) consisting of a first electroconductive film and a second electroconductive film, with the first electroconductive film having a chromium content from 2 wt. % or more, but up to 5 wt. % and the second electroconductive film being provided above the first electroconductive film and containing less chromium than the first electroconductive film does. The use of the data lines composed of these materials enables the following requirements to be satisfied: high dry-etching resistance, low resistance, low ACF contact resistance, low side etching rates, forward tapered wiring cross-sectional shape, and up to two lamination layers.

Claims

1. A liquid crystal display unit comprisingone pair of substrates, a liquid crystal layer held between said pair of substrates, a plurality of scanning lines formed on one of the two substrates, a plurality of data lines which cross said scanning lines in matrix form, thin film transistors formed near the crossing points of said scanning lines and data lines, and pixel electrodes connected to said thin film transistors, wherein the source electrode and drain electrode of each thin film transistor, and each data line, are made of a molybdenum alloy having a chromium content of 2 weight % or more, but up to 5 weight %.

2. A liquid crystal display unit according to claim 1 above, wherein said liquid crystal display unit is characterized in that the channel length of each thin film transistor is 7 μ

m or less.

3. A liquid crystal display unit according to claim 1 or 2 above, wherein said liquid crystal display unit is characterized in that it is so constructed as to bring said molybdenum alloy and an anisotropic conductive film into direct contact at the terminal portion of each data line mentioned above.

4. A liquid crystal display unit according to claim 1 or 2, above, wherein said liquid crystal display unit is characterized in that each scanning line includes aluminum or an aluminum alloy and in that each pixel electrode is constructed using an indium tin oxide or indium zinc oxide composed mainly of an amorphous phase.

5. A liquid crystal display unit according to claim 1 or 2 above, wherein said liquid crystal display unit is characterized in that each scanning line is constructed into a film lamination whose lower layer consists of aluminum or an aluminum alloy and whose upper layer consists of a molybdenum alloy with a zirconium content of 2.6 weight % or more, but up to 23 weight %, and in that each pixel electrode is constructed using an indium tin oxide or indium zinc oxide composed mainly of an amorphous phase.

6. A liquid crystal display unit according to claim 1 or 2 above, wherein said liquid crystal display unit is characterized in that its driver chips are mounted using the Chip-on-Glass (COG) method.

7. A liquid crystal display unit according to claim 6 above, wherein said liquid crystal display unit is characterized in that at least one portion of display data and reference potential data are electrically connected between said driver chips and in that of said two substrates, only the substrate provided with said thin-firm transistors has wiring formed and used as part of said electrical connection.

8. A liquid crystal display unit comprising

one pair of substrates, a liquid crystal layer held between said pair of substrates, a plurality of scanning lines formed on one of the two substrates, a plurality of data lines which cross said scanning signal lines in matrix form, thin film transistors formed near the crossing points of said scanning lines and data lines, and pixel electrodes connected to said thin film transistors, wherein said liquid crystal display unit is characterized in that the source electrode and drain electrode of each thin film transistor, and each data line, are each constructed into a film lamination consisting of a first electroconductive film and a second electroconductive film, in that said first electroconductive film is an alloy composed mainly of molybdenum alloy having a chromium content of 2 weight % or more, but up to 5 weight %, and in that the second electroconductive film is a molybdenum alloy located above the first electroconductive film and lower in chromium content than the first electroconductive film.

9. A liquid crystal display unit according to claim 8 above, wherein said liquid crystal display unit is characterized in that the channel length of each thin film transistor is 7 μ

m or less.

10. A liquid crystal display unit according to claim 8 or 9 above, wherein said liquid crystal display unit is characterized in that it is so constructed as to bring said molybdenum alloy and the anisotropic conductive films into direct contact at the terminal portion of each data line mentioned above.

11. A liquid crystal display unit according to claim 8 or 9 above, wherein said liquid crystal display unit is characterized in that each scanning line includes aluminum or an aluminum alloy and in that each pixel electrode is constructed using an indium tin oxide or indium zinc oxide composed mainly of an amorphous phase.

12. A liquid crystal display unit according to claim 8 or 9 above, wherein said liquid crystal display unit is characterized in that each scanning line is constructed into a film lamination whose lower layer consists of aluminum or an aluminum alloy and whose upper layer consists of a molybdenum alloy with a zirconium content of 2.6 weight % or more, but up to 23 weight %, and in that each pixel electrode is constructed using an indium tin oxide or indium zinc oxide composed mainly of an amorphous phase.

13. A liquid crystal display unit according to claim 8 or 9 above, wherein said liquid crystal display unit is characterized in that its driver chips are mounted using the Chip-on-Glass (COG) method.

14. A liquid crystal display unit according to claim 13 above, wherein said liquid crystal display unit is characterized in that at least one portion of display data and reference potential data are electrically connected between said driver chips and in that of said two substrates, only the substrate provided with said thin-firm transistors has wiring formed and used as part of said electrical connection.

15. A liquid crystal display unit comprising one pair of substrates, a liquid crystal layer held between said pair of substrates, a plurality of scanning lines formed on one of the two substrates, a plurality of data lines which cross said scanning lines in matrix form, thin film transistors formed near the crossing points of said scanning lines and data lines, and at least one pair of pixel electrodes and opposed electrodes formed on one of said two substrates in a plurality of pixels in an area enclosed with said scanning lines and data lines;

said pixel electrodes being supplied with data signals via said thin film transistors driven in accordance with the scanning supplied from the scanning signal lines, and said opposed electrodes being supplied with reference voltages via opposed voltage signal lines formed over said pixels, wherein said liquid crystal display unit is characterized in that the data lines and the pixel electrodes are each made of an alloy consisting mainly of molybdenum alloy with a chromium content of 2 weight % or more, but up to 5 weight %.

16. A liquid crystal display unit according to claim 15 above, wherein said liquid crystal display unit is characterized in that the source electrode and drain electrode of each thin film transistor are the same in film structure as said data lines and pixel electrodes, and in that the channel length of the thin film transistor is 7 μ

m or less.

17. A liquid crystal display unit according to claim 15 or 16 above, wherein said liquid crystal display unit is characterized in that each of said scanning lines includes aluminum or an aluminum alloy.

18. A liquid crystal display unit according to claim 15 or 16 above, wherein said liquid crystal display unit is characterized in that each scanning line is constructed into a film lamination whose lower layer consists of aluminum or an aluminum alloy and whose upper layer consists of a molybdenum alloy with a zirconium content of 2.6 weight % or more, but up to 23 weight %.

19. A liquid crystal display unit according to claim 15 or 16 above, wherein said liquid crystal display unit is characterized in that its driver chips are mounted using the Chip-on-Glass (COG) method.

20. A liquid crystal display unit according to claim 19 above, wherein said liquid crystal display unit is characterized in that at least one portion of display data and reference potential data are electrically connected between said driver chips and in that of said two substrates, only the substrate provided with said thin-firm transistors has wiring formed and used as part of said electrical connection.

21. A liquid crystal display unit comprising one pair of substrates, a liquid crystal layer held between said pair of substrates, a plurality of scanning lines formed on one of the two substrates, a plurality of data lines which cross said scanning lines in matrix form, thin film transistors formed near the crossing points of said scanning lines and data lines, and at least one pair of pixel electrodes and opposed electrodes formed on one of said two substrates in a plurality of pixels in an area provided between said scanning lines and data lines;

said pixel electrodes being supplied with data signals via said thin film transistors driven in accordance with the scanning signals supplied from the scanning lines, and said opposed electrodes being supplied with reference voltages via opposed voltage signal lines formed over said pixels, wherein said liquid crystal display unit is characterized in that the data lines and the pixel electrodes are each constructed into a film lamination consisting of a first electroconductive film and a second electroconductive film, in that said first electroconductive film is an alloy consisting mainly of molybdenum alloy with a chromium content of 2 weight % or more, but up to 5 weight %, and in that said second electroconductive film is a molybdenum alloy located above the first electroconductive film and lower in chromium content than the first electroconductive film.

22. A liquid crystal display unit according to claim 21 above, wherein said liquid crystal display unit is characterized in that the source electrode and drain electrode of each thin film transistor are the same in film structure as said data lines and pixel electrodes, and in that the channel length of the thin film transistor is 7 μ

m or less.

23. A liquid crystal display unit according to claim 21 or 22 above, wherein said liquid crystal display unit is characterized in that each of said scanning lines includes aluminum or an aluminum alloy.

24. A liquid crystal display unit according to claim 21 or 22 above, wherein said liquid crystal display unit is characterized in that each scanning signal line is constructed into a film lamination whose lower layer consists of aluminum or an aluminum alloy and whose upper layer consists of a molybdenum alloy with a zirconium content of 2.6 weight % or more, but up to 23 weight %.

25. A liquid crystal display unit according to claim 21 or 22 above, wherein said liquid crystal display unit is characterized in that its driver chips are mounted using the Chip-on-Glass (COG) method.

26. A liquid crystal display unit according to claim 25 above, wherein said liquid crystal display unit is characterized in that at least one portion of display data and reference potential data are electrically connected between said driver chips and in that of said two substrates, only the substrate provided with said thin-firm transistors has wiring formed and used as part of said electrical connection.