Flexible and stretchable sensors formed by patterned spalling
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.
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 2E 12 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/cm 3 to 1E19 atoms/cm 3 .
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.