Fiber comprising micro devices and metal interconnects with controlled elasticity

Patent metadata

Field	Value
Publication number	US-12494302-B2
Application number	US-202318332326-A
Country	US
Kind code	B2
Filing date	Jun 9, 2023
Priority date	Aug 12, 2022
Publication date	Dec 9, 2025
Grant date	Dec 9, 2025

Abstract

An elastic and conductive fiber includes a cladding with a channel and a conductor disposed therein. The cladding may be made of a thermoplastic elastomer. The conductive fiber includes an excess length of conductor disposed inside of the channel so that the conductive fiber can stretch without applying substantial strain to the conductor and without substantially changing the electrical resistance of the conductive fiber. The conductor inside of the channel may have a buckled shape or a helical shape.

First claim

The invention claimed is:

1 . A fiber comprising:
a cladding including a channel formed therein; and a conductor disposed in the channel, the conductor having a buckled shape and a length longer than a length of the cladding by about 4% to about 100%, wherein the channel has a cross-sectional diameter about 5 to about 500 times larger than a cross-sectional diameter of the conductor.

2 . The fiber of claim 1 , wherein the conductor has a length that is at least 20% longer than the length of the cladding.

3 . The fiber of claim 1 , wherein a length of the fiber is at least about 1000 times longer than a width of the fiber.

4 . The fiber of claim 1 , wherein the conductor comprises a first wire and further comprising a second wire.

5 . The fiber of claim 1 , wherein the channel is a first channel, the conductor is a first conductor, the cladding includes a second channel formed therein, and further comprising a second conductor disposed in the second channel.

6 . The fiber of claim 1 , further comprising at least one device electrically coupled to the conductor and disposed in the channel.

7 . The fiber of claim 6 , wherein the at least one device is electrically coupled to the conductor in series.

8 . The fiber of claim 6 , wherein the conductor is a first conductor, and further comprising:
a second conductor embedded in the cladding, wherein the at least one device is electrically coupled in parallel to the first conductor and the second conductor.

9 . The fiber of claim 6 , wherein the at least one device comprises at least one of a diode, a photodiode, a light emitting diode, a laser diode, a photodetector, or a transistor.

10 . The fiber of claim 6 , wherein the at least one device comprises at least one of a memory chip, a processor, a microcontroller, or a thermistor.

11 . The fiber of claim 1 , wherein the cladding comprises a thermoplastic elastomer material.

12 . The fiber of claim 11 , wherein the thermoplastic elastomer material comprises at least one of poly (styrene-b-(ethylene-co-butylene)-b-styrene), thermoplastic polyurethane, or cyclic olefin copolymer elastomer.

13 . The fiber of claim 1 , wherein the conductor comprises a conductive metal.

14 . The fiber of claim 13 , wherein the conductive metal comprises at least one of copper, tungsten, iron, aluminum, titanium, chromium, nickel, gold, or silver.

15 . The fiber of claim 1 wherein the conductor has a conductivity of at least 10 7 S m −1 .

16 . The fiber of claim 1 , wherein:
the cladding comprises cyclic olefin copolymer elastomer, the conductor comprises copper, the length of the conductor is about 20% to about 30% longer than the length of the cladding, and the fiber has a diameter of about 1 mm to about 4 mm.

17 . A fabric comprising the fiber of claim 1 woven or knitted into the fabric.

18 . A method comprising:
forming a fiber comprising a cladding and a portion of a conductor disposed in a channel formed in the cladding; stretching the cladding along a longitudinal axis of the fiber to pull a second portion of the conductor into the channel; and after stretching the cladding, relaxing the cladding to induce buckling of the conductor in the channel, wherein the channel has a cross-sectional diameter about 5 to about 500 times larger than a cross-sectional diameter of the conductor.

19 . The method of claim 18 , wherein buckling of the conductor causes the conductor to have a length that is at least 20% longer than a length of the fiber.

20 . A fiber comprising:
a cladding including a channel formed therein; a conductor disposed in the channel, the conductor having a buckled shape and a length longer than a length of the cladding by about 4% to about 100%; and at least one device electrically coupled to the conductor and disposed in the channel, wherein the at least one device is electrically coupled to the conductor in series.

21 . A fiber comprising:
a cladding including a channel formed therein; and a solid metal conductor disposed in the channel, the solid metal conductor having a buckled shape and a length longer than a length of the cladding by about 4% to about 100%.

Assignees

• Massachusetts Inst Technology

Inventors

• Marion Juliette
• Anikeeva Polina Olegovna
• Fink Yoel

Classifications

• D04B1/16

  synthetic threads · CPC title

• D10B2401/061

  elastic · CPC title

• D03D15/30

  characterised by the structure of the fibres or filaments · CPC title

• D03D15/283

  synthetic polymer-based, e.g. polyamide or polyester fibres (cellulose-based artificial fibres D03D15/225) · CPC title

• D03D15/25

  Metal · CPC title