Strain isolation structures for stretchable electronics

• US 9,844,145 B2
• Filed: 06/28/2016
• Issued: 12/12/2017
• Est. Priority Date: 06/11/2012
• Status: Active Grant

• Current Assignee: Medidata Solutions Incorporated (Dassault Systemes SA)
• Original Assignee: MC10, Inc.
• Inventors: Hsu, Yung-Yu
• Primary Examiner(s): Tran, Binh
• Application Number:
  US15/194,995
• Publication Number:
  US 20160309594A1
• Time in Patent Office: 532 Days
• Field of Search: 361749, 361784, 361789
• CPC Class Codes: H05K 1/0271 Arrangements for reducing stress or warp in rigid printed circuit boards, e.g. caused by loads, vibrations or differences in thermal expansion
• CPC Class Codes: H05K 1/028 Bending or folding regions of flexible printed circuits H05K1/0283 takes precedence
• CPC Class Codes: H05K 1/0283 Stretchable printed circuits
• CPC Class Codes: H05K 1/036 Multilayers with layers of different types
• 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 1/09 Use of materials for the conductive, e.g. metallic pattern
• CPC Class Codes: H05K 1/118 specially for flexible printed circuits, e.g. using folded portions
• CPC Class Codes: H05K 1/147 at least one of the printed circuits being bent or folded, e.g. by using a flexible printed circuit H05K1/148 takes precedence
• CPC Class Codes: H05K 1/148 Arrangements of two or more hingeably connected rigid printed circuit boards, i.e. connected by flexible means
• CPC Class Codes: H05K 1/185 Components encapsulated in the insulating substrate of the printed circuit or incorporated in internal layers of a multilayer circuit semiconductor chips encapsulated by interconnect and support structures H01L23/5389, H01L24/00
• CPC Class Codes: H05K 1/189 characterised by the use of a flexible or folded printed circuit H05K3/326 takes precedence
• CPC Class Codes: H05K 2201/0133 Elastomeric or compliant polymer elastomeric conductor H05K2201/0314
• CPC Class Codes: H05K 2201/0154 Polyimide
• CPC Class Codes: H05K 2201/0187 with regions of different dielectrics in the same layer, e.g. in a printed capacitor for locally changing the dielectric properties
• CPC Class Codes: H05K 2201/09245 Crossing layout alternating conductors H05K2201/097
• CPC Class Codes: H05K 2201/1028 Thin metal strips as connectors or conductors
• CPC Class Codes: H05K 2201/10287 Metal wires as connectors or conductors
• CPC Class Codes: H05K 2201/2009 Reinforced areas, e.g. for a specific part of a flexible printed circuit
• CPC Class Codes: H05K 3/4691 Rigid-flexible multilayer circuits comprising rigid and flexible layers, e.g. having in the bending regions only flexible layers
• CPC Class Codes: H05K 3/4694 Partitioned multilayer circuits having adjacent regions with different properties, e.g. by adding or inserting locally circuit layers having a higher circuit density H05K3/4691 takes precedence

Abstract

Buffer structures are provided that can be used to reduce a strain in a conformable electronic system that includes compliant components in electrical communication with more rigid device components. The buffer structures are disposed on, or at least partially embedded in, the conformable electronic system such that the buffer structures overlap with at least a portion of a junction region between a compliant component and a more rigid device component. The buffer structure can have a higher value of Young'"'"'s modulus than an encapsulant of the conformable electronic system.

Claims

1. An apparatus comprising:

a device component;

a conductive stretchable interconnect electrically coupled with the device component at a junction region;

a first buffer structure including a first buffer structure main body, a first projection portion, and a second projection portion, the first projection portion extending outwardly from the first buffer structure main body and being disposed along a first side of the conductive stretchable interconnect, the second projection portion extending outwardly from the first buffer structure main body and being disposed along a second opposing side of the conductive stretchable interconnect;

a second buffer structure including a second buffer structure main body, a third projection portion, and a fourth projection portion, the third projection portion extending outwardly from the second buffer structure main body and being disposed along the first side of the conductive stretchable interconnect, the fourth projection portion extending outwardly from the second buffer structure main body and being disposed along the second opposing side of the conductive stretchable interconnect; and

an encapsulant encapsulating the device component, the junction region, and the buffer structure.

2. The apparatus of claim 1, wherein the first buffer structure main body has a disk shape.

3. The apparatus of claim 2, wherein the first projection portion and the second projection portion each have a polygonal shape.

4. The apparatus of claim 2, wherein the first buffer structure is positioned such that at least a portion of the first buffer structure main body overlaps with the device component.

5. The apparatus of claim 1, wherein the first buffer structure is positioned such that at least a portion of the first buffer structure contacts the device component or the conductive stretchable interconnect.

6. The apparatus of claim 1, wherein the first buffer structure is positioned such that at least a portion of the encapsulant extends between the first buffer structure and the device component.

7. The apparatus of claim 1, wherein the first buffer structure main body has an annular shape.

8. The apparatus of claim 1, wherein the first buffer structure main body has a torus shape.

9. The apparatus of claim 1, wherein the second buffer structure is positioned such that at least a portion of the device component or the conductive stretchable interconnect is disposed between the first buffer structure and the second buffer structure.

10. The apparatus of claim 1, wherein a central point of the first buffer structure and a central point of the second buffer structure are generally coincident with each other.