Stretchable electronic device

Patent metadata

Field	Value
Publication number	US-11516909-B2
Application number	US-201917053483-A
Country	US
Kind code	B2
Filing date	May 21, 2019
Priority date	May 25, 2018
Publication date	Nov 29, 2022
Grant date	Nov 29, 2022

Abstract

An electronic device (100) comprises a stretchable substrate (30) with a flap (30f) formed by a cut (40) in the substrate (30). The flap (30f) is disconnected by the cut (40) from a surrounding main section (30m) of the substrate (30) except on one side. The flap (30f) is exclusively connected to the main section (30m) via a connected section (30c) of the substrate (30) between two ends (40a, 40b) of the cut (40). An electronic component (10) is disposed on the flap (30f) with electrical contacts (11,12) connected to conductive tracks (21,22) disposed on the substrate (30). The conductive tracks (21,22) extend between the component (10) disposed on the flap (30f), and other parts (10r) of the electronic device (100) outside the flap (30f) via the connected section (30c). The flap (30f) with the component (10) is disposed in a pocket formed by surrounding lamination layers (31,32).

First claim

The invention claimed is:

1. An electronic device comprising: a stretchable substrate with a flap formed by a U-shaped cut in the stretchable substrate, wherein the flap is: disconnected by the U-shaped cut from a main section of the stretchable substrate except on one side, and exclusively connected to the main section via a connected section of the substrate between a first end and a second end of the U-shaped cut; an electronic component disposed on the flap with electrical contacts connected to conductive tracks disposed on the substrate, wherein the conductive tracks extend between the electronic component disposed on the flap, and other parts of the electronic device outside the flap via the connected section; and a first lamination layer and a second lamination layer on opposing sides of the stretchable substrate, wherein the flap with the electronic component is disposed in a pocket formed between the first lamination layer and the second lamination layer, wherein the first and second lamination layers are exclusively adhered to the main section of the stretchable substrate so the flap with the electronic component is exclusively attached to the first and second lamination layers via the connected section of the stretchable substrate; wherein the electronic component is globtopped by a solid material disposed entirely on the flap.

2. The electronic device according to claim 1 , wherein the electronic component is disposed entirely on the flap surrounded on all but one side by the cut, wherein the electronic component is distanced by a flap margin from an edge of the connected section.

3. The electronic device according to claim 1 , wherein the U-shaped cut extends in different directions over a cut length around a perimeter of the component, wherein the U-shaped cut extends between the first end and the second end of the U-shaped cut over an angle in a plane of the substrate around a center of the electronic component, and wherein the angle is at least two-hundred-fifty degrees.

4. The electronic device according to claim 1 , wherein a width of the flap tapers at the connected section.

5. The electronic device according to claim 1 , wherein the U-shaped cut has a semi-circular or a semi-oval shape.

6. The electronic device according to claim 1 , wherein the stretchable substrate is stretchable to reversibly expand a size of the stretchable substrate along one or more dimensions by at least ten percent without breaking.

7. The electronic device according to claim 1 , wherein the stretchable substrate has an elastic modulus lower than an elastic modulus of the electronic component, by at least a factor ten.

8. The electronic device according to claim 1 , wherein the stretchable substrate has a Young's modulus of less than one gigapascal at 25° C.

9. The electronic device according to claim 1 , comprising a plurality of components disposed on a respective plurality of flaps.

10. The electronic device according to claim 1 , wherein a length of the electronic component is more than a width of the electronic component, wherein the electronic component is arranged with a longer of the electronic component facing a connected edge of the flap, and wherein the conductive tracks approach and reach the electronic component exclusively from one or both of longer sides of the electronic component.

11. The electronic device according to claim 1 , wherein the conductive tracks pass below the electronic component between the electronic component and substrate to approach the electrical contacts from a center of the electronic component outward.

12. The electronic device according to claim 1 , wherein the conductive tracks comprise a first conductive and a second conductive track that approach the electronic component from opposing sides of the electronic component, wherein the first conductive track curls around the electronic component to approach from a side of the electronic component opposite the connected section, and wherein the second conductive track approaches the electronic component directly from a side of the connected section.

13. A method of manufacturing an electronic device, the method comprising: creating a U-shaped cut in a stretchable substrate to provide a flap in the stretchable substrate, wherein the flap is: disconnected by the U-shaped cut from a main section of the stretchable substrate except on one side, and exclusively connected to the main section via a connected section of the substrate between a first end and a second end of the U-shaped cut; providing an electronic component on the flap with electrical contacts connected to conductive tracks disposed on the substrate, wherein the conductive tracks extend between the component disposed on the flap, and other parts of the electronic device outside the flap via the connected section; and providing a first lamination layer and a second layer on opposing sides of the stretchable substrate, wherein the flap with the electronic component is disposed in a pocket formed between the first lamination layer and the second lamination layer, wherein the first and second lamination layers are exclusively adhered to the main section of the stretchable substrate so the flap with the electronic component is exclusively attached to the first and second lamination layers via the connected section of the stretchable substrate; wherein the electronic component is globtopped by a solid material disposed entirely on the flap.

14. The method according to claim 13 , wherein a first intermediate adhesive layer and a second intermediate adhesive layer are provided exclusively between the main section of the substrate and the first and second lamination layers.

Assignees

• TNO

Inventors

• Barink Marco
• Smits Edsger Constant Pieter
• Van Den Brand Jeroen

Classifications

• H05K1/189 Primary

  characterised by the use of flexible or folded printed circuits · CPC title

• H05K3/281

  by means of a preformed insulating foil (H05K3/284 takes precedence) · CPC title

• H05K2201/09281

  Layout details of a single conductor · CPC title

• H05K1/0277

  Bendability or stretchability details (H05K1/038, H05K3/4691 take precedence) · CPC title

• H05K2201/0129

  Thermoplastic polymer, e.g. auto-adhesive layer; Shaping of thermoplastic polymer · CPC title