Transparent substrate with invisible electrodes and device incorporating the same

• US 7,843,061 B2
• Filed: 11/30/2004
• Issued: 11/30/2010
• Est. Priority Date: 12/01/2003
• Status: Active Grant

• Current Assignee: The Swatch Group Research And Development Ltd
• Original Assignee: Asulab SA (The Swatch Group AG)
• Inventors: Grupp, Joachim, Poli, Gian-Carlo, Baroni, Pierre-Yves
• Primary Examiner(s): Wilson; Allan R.
• Assistant Examiner(s): Chen; Yu
• Application Number:
  US10/998,800
• Publication Number:
  US 20050116343A1
• Time in Patent Office: 2,191 Days
• Field of Search: 257/43, 257/449, 257/617, 257/746, 257/749, 257/59, 257/72, 257/448, 257/E31.126, 257/E23.015, 977/781, 977/784, 977/780, 349/143
• US Class Current: 257/749
• CPC Class Codes: G02F 1/13439 characterised by their electrical, optical, physical properties; materials therefor; method of making
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: Y02E 10/50 Photovoltaic [PV] energy
• CPC Class Codes: Y10S 977/781 Possessing nonosized surface openings that extend partially into or completely through the host material
• CPC Class Codes: Y10S 977/784 Electrically conducting, semi-conducting, or semi-insulating host material

Abstract

The electrodes (7) and the contact zones (15) are structured in a film of a transparent conductive oxide (TCO), deposited on a transparent support (1) possibly coated with an intermediate film (3), while being separated by dielectric spaces (9) formed by nano fissures (11) obtained by UV radiation and passing through the TCO film. A protective film (13) can coat the electrodes (7) and the dielectric spaces (9).

Claims

1. A transparent substrate with invisible electrodes, the transparent substrate including:

(a) a transparent support; and

(b) a transparent conductive film deposited on the transparent support,

wherein the transparent conductive film includes invisible electrodes having invisible contact zones, structured with contours separated by non-conductive spaces, wherein the non-conductive spaces include nano fissures formed in the conductive film so as to interrupt electrical conductivity between neighbouring electrodes, and so as to form the invisible electrodes and the invisible contact zones, and wherein the nano fissures have a maximum width of about 500 nanometers.

2. The substrate according to claim 1, wherein the transparent conductive film is a transparent conductive oxide (TCO), selected from the group consisting of tin and indium oxide (ITO), In₂O₃ and SnO₂ doped with Sb.

3. The substrate according to claim 2, wherein the conductive film is an ITO film having a thickness of between 50 and 100 nm.

4. The substrate according to claim 2, wherein the conductive film is an ITO film having a thickness of between 65 and 75 nm.

5. The substrate according to claim 1, wherein the transparent conductive film is a doped conductive polymer with conjugated double bonds, selected from the group consisting of a polyacetylene and polyanilines.

6. The substrate according to claim 1, wherein an intermediate layer made of a transparent hard non-conductive material or hard coating is inserted between the support and the conductive film.

7. The substrate according to claim 6, wherein the intermediate layer is formed of a resin incorporating SiO₂ and having a thickness at least equal to 20 μ

m.

8. The substrate according to claim 1, wherein the majority of the nano fissures pass through the entire conductive film.

9. The substrate according to claim 1, wherein the support is made of a material selected from the group consisting of polymethylene methacrylate (PMMA) and polycarbonate (PC).

10. The substrate according to claim 1, wherein the electrodes and the non-conductive spaces are further coated with a protective film that have anti-reflective properties.

11. The substrate according to claim 10, wherein the protective film does not cover the contact zones of the electrodes.

12. The substrate according to claim 1, wherein the substrate forms a touch-type control screen for an electronic apparatus in which the substrate is integrated.

13. The substrate according to claim 1, wherein the substrate forms at least one closing plate for a liquid crystal display cell or a photovoltaic cell for an electronic apparatus.