Flexible and stretchable sensors formed by patterned spalling

• US 9,874,534 B2
• Filed: 11/01/2016
• Issued: 01/23/2018
• Est. Priority Date: 11/20/2015
• Status: Active Grant

• Current Assignee: International Business Machines Corporation
• Original Assignee: International Business Machines Corporation
• Inventors: Bedell, Stephen W., Han, Shu-Jen, Li, Ning, Sadana, Devendra K.
• Primary Examiner(s): Ha, Nathan W
• Application Number:
  US15/340,550
• Publication Number:
  US 20170146474A1
• Time in Patent Office: 448 Days
• CPC Class Codes: A61B 2562/164 the sensor is mounted in or on a conformable substrate or carrier
• CPC Class Codes: G01N 27/04 by investigating resistance
• CPC Class Codes: H01L 21/02524 Group 14 semiconducting materials
• CPC Class Codes: H01L 24/83 using a layer connector
• CPC Class Codes: H01L 27/0288 using passive elements as protective elements, e.g. resistors, capacitors, inductors, spark-gaps
• CPC Class Codes: H01L 27/0802 Resistors only
• CPC Class Codes: H01L 28/20 Resistors
• CPC Class Codes: H10N 30/85 Piezoelectric or electrostrictive active materials

Abstract

A material removal process referred to as spalling is used to provide flexible and stretchable sensors that can be used for healthcare monitoring, bio-medical devices, wearable electronic devices, artificial skin, large area sensing, etc. The flexible and stretchable sensors of the present application have high sensitivity that is comparable to that of a bulk silicon sensor. The flexible and stretchable sensors comprise single crystalline spring-like structures that couple various resistor structures together.

Claims

1. A structure comprising:

a flexible and stretchable sensor embedded within a flexible substrate, said flexible and stretchable sensor comprising a single crystalline spring-like structure coupling a neighboring pair of resistor structures together; and

at least one other flexible and stretchable sensor embedded within said flexible substrate, said at least one other flexible and stretchable sensor comprising another single crystalline spring-like structure coupling another neighboring pair of resistor structures together.

2. The structure of claim 1, wherein said single crystalline spring-like structure is a single crystalline semiconductor material.

3. The structure of claim 2, wherein said single crystalline semiconductor material is silicon.

4. The structure of claim 1, wherein each resistor structure comprises a doped semiconductor material.

5. The structure of claim 4, wherein said doped semiconductor material and said single crystalline spring-like structure both comprise a same semiconductor material.

6. The structure of claim 1, wherein said flexible substrate is a tape.

7. The structure of claim 1, wherein a surface of each resistor structure is exposed.

8. The structure of claim 7, wherein said surface of each resistor is coplanar with a topmost surface of said flexible substrate.

9. The structure of claim 1, wherein single crystalline spring-like structure is located directly beneath each resistor structure.

10. The structure of claim 1, wherein said single crystalline spring-like structure has a piezoelectric coefficient of from 2E¹² mV or greater.

11. The structure of claim 2, wherein said single crystalline semiconductor material is composed of Ge, SiGe, SiGeC, SiC, a III-V compound semiconductor or a II-VI compound semiconductor.

12. The structure of claim 4, wherein said doped semiconductor material comprises a p-type semiconductor material.

13. The structure of claim 4, wherein said doped semiconductor material comprises an n-type semiconductor material.

14. The structure of claim 4, wherein aid doped semiconductor material has a dopant concentration of from 1E16 atoms/cm³ to 1E19 atoms/cm³.

15. The structure of claim 1, wherein each resistor comprises doped polysilicon.

16. The structure of claim 1, wherein each resistor comprises a ceramic.

17. The structure of claim 1, wherein each resistor comprises a carbon film.

18. The structure of claim 1, wherein each resistor comprises a metal oxide.