Method of making an electrical circuit

• US 8,307,549 B2
• Filed: 04/20/2004
• Issued: 11/13/2012
• Est. Priority Date: 11/20/2001
• Status: Expired due to Term

• Current Assignee: Touchsensor Technologies LLC (Methode Electronics Incorporated)
• Original Assignee: Touchsensor Technologies LLC (Methode Electronics Incorporated)
• Inventors: Caldwell, David W., Taylor, Michael Jon, Marshall, Michael L.
• Primary Examiner(s): ARBES, CARL J
• Application Number:
  US10/828,997
• Publication Number:
  US 20050020062A1
• Time in Patent Office: 3,129 Days
• Field of Search: 298/25, 298/32, 298/40, 298/46, 298/47, 298/52, 430/316, 438/316
• US Class Current: 29/847
• CPC Class Codes: C23C 14/562 for coating elongated substrates
• CPC Class Codes: G06F 2203/04113 Peripheral electrode pattern in resistive digitisers, i.e. electrodes at the periphery of the resistive sheet are shaped in patterns enhancing linearity of induced field
• CPC Class Codes: H01L 31/0232 Optical elements or arrangements associated with the device H01L31/0236 takes precedence; for photovoltaic cells H01L31/054; for photovoltaic modules H02S40/20
• CPC Class Codes: H05K 1/02 Details
• CPC Class Codes: H05K 1/0393 Flexible materials H05K1/038 takes precedence; specific organic compositions are classified in H05K1/0313 and subgroups
• CPC Class Codes: H05K 2201/0108 Transparent
• CPC Class Codes: H05K 2201/0326 Inorganic, non-metallic conductor, e.g. indium-tin oxide [ITO]
• CPC Class Codes: H05K 2203/0361 Stripping a part of an upper metal layer to expose a lower metal layer, e.g. by etching or using a laser
• CPC Class Codes: H05K 2203/1545 Continuous processing, i.e. involving rolls moving a band-like or solid carrier along a continuous production path
• CPC Class Codes: H05K 3/06 the conductive material being removed chemically or electrolytically, e.g. by photo-etch process semi-additive methods H05K3/108
• CPC Class Codes: H05K 3/24 Reinforcing the conductive pattern by solder coating H05K3/3457
• CPC Class Codes: Y10T 29/49117 Conductor or circuit manufacturing
• CPC Class Codes: Y10T 29/49155 Manufacturing circuit on or in base
• CPC Class Codes: Y10T 29/49156 with selective destruction of conductive paths
• CPC Class Codes: Y10T 29/49165 by forming conductive walled aperture in base

Abstract

A layer of transparent conductive material is disposed on a surface of a substrate. Further layers of conductive material are deposited on the layer of transparent conductive material or on an opposite surface of the substrate. The layers are selectively etched to yield a layout of pads for mounting electrical components and conductive traces forming an electrical circuit.

Claims

1. A method for fabricating an electrical circuit, comprising the steps of:

depositing a layer of a first conductive material onto a surface of a flexible substrate, wherein said layer of a first conductive material is substantially transparent and wherein at least a portion of said substrate is translucent or transparent;

depositing a layer of a second conductive material onto said layer of a first conductive material;

depositing an additional layer of conductive material onto said layer of a second conductive material;

selectively etching said layer of additional conductive material;

selectively etching a portion of said layer of a second conductive material; and

selectively etching a portion of said layer of a first conductive material.

2. The method of claim 1 wherein said first conductive material is indium tin oxide.

3. The method of claim 1 wherein said second conductive material is a conventional conductive material.

4. The method of claim 3 wherein said second conductive material is copper.

5. The method of claim 1 wherein said steps of selectively etching occur after said steps of depositing.

6. The method of claim 5 further comprising the steps of:

providing said flexible substrate on a supply roll; and

unrolling said flexible substrate from said supply roll;

wherein said steps of depositing said layer of a first conductive material onto said flexible substrate and depositing said layer of a second conductive material onto said layer of a first conductive material are conducted on a continuous basis.

7. The method of claim 6 further comprising the step of rolling said flexible substrate with said layers of conductive material applied thereto onto a take-up roll.

8. The method of claim 1 wherein said additional layer of conductive material is deposited by electroplating.

9. The method of claim 3 further comprising the step of electrically connecting an electrical component to said second conductive material.

10. The method of claim 5 wherein said step of electrically connecting said electrical component to said second conductive material comprises soldering said electrical component to said second conductive material.

11. The method of claim 1 wherein said layer of second conductive material is substantially transparent.

12. The method of claim 1 wherein said second conductive material is an oxide of niobium.

13. The method of claim 11 wherein said additional layer of conductive material comprises a conventional conductive material.

14. The method of claim 1 further comprising the step of electrically connecting an electrical component to said additional layer of conductive material.

15. The method of claim 14 wherein said step of electrically connecting said electrical component to said additional layer of conductive material comprises soldering said electrical component to said additional layer of conductive material.

16. The method of claim 1 wherein at least one of said steps of depositing occurs in a substantial vacuum.

17. The method of claim 1 further comprising the step of pretreating said surface of said substrate to enhance adhesion of said layer of first conductive material to said substrate.

18. The method of claim 1 further comprising the step of patterning said layer of a second conductive material to define said portion of said layer of a second conductive material to be etched in connection with said step of etching said layer of a second conductive material.

19. The method of claim 18 further comprising the step of patterning said layer of a first conductive material to define said portion of said layer of a first conductive material to be etched in connection with said step of etching said layer of a first conductive material.

20. The method of claim 1 further comprising the step of patterning said layer of a first conductive material to define said portion of said layer of a first conductive material to be etched in connection with said step of etching said layer of a first conductive material.

21. The method of claim 1 wherein said step of selectively etching said layer of a second conductive material is performed using an etchant that is selected to etch said layer of a second conductive material and to not substantially etch said layer of a first conductive material.

22. The method of claim 1 wherein said substrate is supplied to and taken up from a support drum that supports said substrate during said steps of depositing.

23. The method of claim 13 wherein said additional layer of conductive material comprises copper.

24. A method for fabricating an electrical circuit, comprising the steps of:

depositing a layer of a first conductive material onto a surface of a substrate, either directly or in connection with an intermediary layer between said layer of a first conductive material and said surface of a substrate;

depositing a layer of a second conductive material onto said layer of a first conductive material in connection with an interfacial layer deposited between said layer of a second conductive material and said layer of a first conductive material;

selectively etching a portion of said layer of a second conductive material;

selectively etching a portion of said interfacial layer; and

selectively etching a portion of said layer of a first conductive material.

25. The method of claim 24 wherein said step of etching said layer of a second conductive material is performed using an etchant that etches said layer of a second conductive material and that does not substantially etch said layer of a first conductive material.

26. The method of claim 24 wherein said layer of a first conductive material is substantially transparent.