Mechanical and electrical interconnects between conductive threads in fabrics to PCB, FPC, and rigid-flex circuits

Patent metadata

Field	Value
Publication number	US-9936581-B1
Application number	US-201715729482-A
Country	US
Kind code	B1
Filing date	Oct 10, 2017
Priority date	Oct 11, 2016
Publication date	Apr 3, 2018
Grant date	Apr 3, 2018

Abstract

An electrically interconnected assembly is a technology enabler for mechanical and electrical interconnects between conductive threads, such as those within fabrics and textiles, to electrical connection points, such as contact pads on a printed circuit board (PCB), a flexible printed circuit (FPC), and/or rigid-flexible circuit board. The electrically interconnected assembly uses an anisotropic conductive coated fabric to make an electrical and mechanical interconnect in fabrics or textiles. All fabrics or textiles can be anisotropic conductive coated and cut into sheet form or supplied in roll form.

First claim

What is claimed is:

1. An electrically interconnected assembly comprising:
a. an electronic device having a first surface and one or more electrical connection points on the first surface;
b. a first anisotropic conductive film having a first surface and a second surface opposing the first surface, wherein the first anisotropic conductive film is conductive along a z-axis that is perpendicular to the first surface and the second surface, further wherein the second surface of the first anisotropic film is coupled to the first surface of the electronic device;
c. one or more electrically conductive threads, at least a first portion of each electrically conductive thread is coupled to the first surface of the first anisotropic conductive film, and a second portion of the first portion of each electrically conductive thread is aligned with a corresponding one of the electrical connection points to form an electrical interconnection between the second portion of each electrically conductive thread and the corresponding one electrical connection point;
d. a second anisotropic conductive film having a first surface and a second surface opposing the first surface, wherein the second surface of the second anisotropic is coupled to the first surface of the first anisotropic conductive film with the first portion of each electrically conductive thread sandwiched in between the first anisotropic conductive film and the second anisotropic conductive film; and
e. a fabric coupled to the first surface of the second anisotropic conductive film.

2. The electrically interconnected assembly of claim 1 wherein the one or more electrically conductive threads are physically separated from each other.

3. The electrically interconnected assembly of claim 1 wherein the first anisotropic conductive film and the second anisotropic conducting film are non-conducting along a longitudinal plane perpendicular to the z-axis.

4. The electrically interconnected assembly of claim 1 wherein the first anisotropic conductive film comprises a plurality of electrically conductive particles intermixed within an adhesive.

5. The electrically interconnected assembly of claim 1 wherein each electrical connection point comprises a contact pad or solder bump.

6. The electrically interconnected assembly of claim 1 wherein the electronic device comprises a circuit board.

7. The electrically interconnected assembly of claim 6 wherein the circuit board comprises one of a flexible circuit board, a rigid printed circuit board, or a rigid-flexible printed circuit board.

8. The electrically interconnected assembly of claim 1 wherein each electrically conductive thread is one of a metal wire, a thread with an electrically conductive plating finish, an electrically conductive polymer or an electrically conductive fiber.

9. The electrically interconnected assembly of claim 1 wherein the first anisotropic conductive film and the anisotropic conductive film are compressed along the z-axis and non-compressed along an x-y plane.

10. A method of fabricating an electrically interconnected assembly, the method comprising:
a. attaching a first surface of a first anisotropic conductive film to a first surface of an electronic device, wherein the first surface of the electronic device includes one or more electrical connection points;
b. attaching at least a first portion of each of one or more electrically conductive threads to a second surface of the first anisotropic conductive film, and a second portion of the first portion of each electrically conductive thread is aligned with a corresponding one of the electrical connection points, wherein the attached electronic device, first anisotropic conductive film, and one or more electrically conductive threads form a sub-assembly;
c. attaching a first surface of a second anisotropic conductive film to a fabric to form a cap structure;
d. stacking the cap structure onto the sub-assembly such that a second surface of the second anisotropic conductive film is positioned on the first portions of the one or more conductive threads;
e. applying heat and pressure to the stacked cap structure and sub-assembly to form an electrical interconnection between the second portion of each electrically conductive thread and the corresponding one electrical connection point via the first and second anisotropic conductive films.

11. The method of claim 10 wherein applying pressure comprises compressing the first anisotropic conductive film along a z-axis that is perpendicular to the first surface and the second surface of the first anisotropic conductive film, and compressing the second anisotropic conductive film along the z-axis that is perpendicular to a second surface of the second anisotropic conductive film that opposes the first surface of the second anisotropic conductive film.

12. The method of claim 11 wherein the first anisotropic conductive film and the second anisotropic conductive film become conducting along the z-axis due to the applied pressure along the z-axis.

13. The method of claim 12 wherein the first anisotropic conductive film and the second anisotropic conducting film are non-conducting along a longitudinal plane perpendicular to the z-axis.

14. The method of claim 10 wherein the one or more electrically conductive threads are physically separated from each other.

Assignees

• Flex Ltd

Inventors

• Bergman Mark

Classifications

• H05K3/4635

  laminating flexible circuit boards using additional insulating adhesive materials between the boards · CPC title

• H05K1/144 Primary

  Stacked arrangements of planar printed circuit boards · CPC title

• H05K3/22

  Secondary treatment of printed circuits {(H05K3/1283 takes precedence; embedding circuits in grooves by pressure H05K3/107)} · CPC title

• H05K1/028

  Bending or folding regions of flexible printed circuits (H05K1/0283 takes precedence) · CPC title

• H05K1/118 Primary

  specially for flexible printed circuits, e.g. using folded portions · CPC title