Micromechanical structure comprising carbon material and method for fabricating the same

Patent metadata

Field	Value
Publication number	US-10106398-B2
Application number	US-201514724224-A
Country	US
Kind code	B2
Filing date	May 28, 2015
Priority date	May 28, 2015
Publication date	Oct 23, 2018
Grant date	Oct 23, 2018

Abstract

A micromechanical structure comprises a substrate and a functional structure arranged at the substrate. The functional structure comprises a functional region which is deflectable with respect to the substrate responsive to a force acting on the functional region. The functional structure comprises a carbon layer arrangement, wherein a basis material of the carbon layer arrangement is a carbon material.

First claim

What is claimed is:

1. A micromechanical structure comprising:
a substrate; and
a functional structure arranged at the substrate;
wherein the functional structure comprises a functional region which is deflectable with respect to the substrate responsive to a force acting on the functional region;
wherein the functional structure comprises a carbon layer arrangement comprising a layer, wherein a basis material of the layer of the carbon layer arrangement is a carbon material;
wherein an average amount of the carbon material within the carbon layer material varies within the layer of the carbon layer arrangement along a thickness direction of the functional structure; and
wherein the carbon material is doped with a dopant of at least one material, and wherein the average amount of the carbon material varies along the thickness direction based on a varying degree of doping of the carbon material with the dopant of the at least one material along the thickness direction, wherein the dopant is a metal, a transition metal and/or a metalloid comprising silicon.

2. The micromechanical structure according to claim 1 , wherein an average amount of the carbon material in the layer of the carbon layer arrangement is at least 90% at a region of the carbon layer arrangement.

3. The micromechanical structure according to claim 1 , wherein the carbon material of the carbon layer arrangement comprises a first portion and a second portion, the first portion having an sp 2 hybridization and the second portion having an sp 3 hybridization, wherein an average amount of the first portion or of the second portion varies within the layer of the carbon layer arrangement along a thickness direction of the functional structure.

4. The micromechanical structure according to claim 1 , wherein the layer of the carbon layer arrangement comprises a doping material of the carbon material, wherein an average concentration of the doping material is at least 0.001% at a region of the carbon layer arrangement.

5. The micromechanical structure according to claim 1 , wherein a base area of the layer of the carbon layer arrangement comprises at least a part of a circular shape, a ring shape, a star shape, a polygon shape, an elliptical shape, a honeycomb structured shape or a combination thereof.

6. The micromechanical structure according to claim 1 , wherein the functional structure is a membrane structure and wherein the micromechanical structure is a part of a sound transducer structure.

7. The micromechanical structure according to claim 1 , wherein the functional structure is a bending beam structure comprising a cantilevered portion and the deflectable functional region.

8. The micromechanical structure according to claim 1 , wherein a lateral extension of the functional structure along a lateral direction perpendicular to a thickness direction is at least 50 times greater than a thickness of the functional structure along the thickness direction.

9. A micromechanical sound transducer comprising the micromechanical structure according to claim 1 .

10. The micromechanical structure according to claim 1 , wherein an average concentration of the at least one material is at least 1018 per cm3 at a region of the carbon layer arrangement.

11. The micromechanical structure according to claim 4 , wherein the doping material is one of a metal material, a nitrogen material, a fluorine material, and a phosphorus material.

12. The micromechanical sound transducer according to claim 9 , wherein the micromechanical sound transducer is a microphone.

13. The micromechanical sound transducer according to claim 9 , wherein the micromechanical sound transducer is a loudspeaker.

14. A micromechanical structure comprising:
a substrate; and
a functional structure arranged at the substrate;
wherein the functional structure comprises a functional region which is deflectable with respect to the substrate responsive to a force acting on the functional region;
wherein the functional structure comprises a base layer arrangement and a functional layer;
wherein a basis material of the functional layer is a carbon material;
wherein an average amount of the carbon material within the functional layer varies along a thickness direction of the functional structure; and
wherein the carbon material is doped with a dopant of at least one material, and wherein the average amount of the carbon material varies along the thickness direction based on a varying degree of doping of the carbon material with the dopant of the at least one material along the thickness direction, wherein the dopant is a metal, a transition metal and/or a metalloid comprising silicon.

15. The micromechanical structure according to claim 14 , wherein the base layer arrangement is a conductive base layer arrangement.

16. The micromechanical structure according to claim 14 , wherein an average amount of the carbon material in the functional layer is at least 90% at a region of the functional layer.

17. The micromechanical structure according to claim 14 , wherein the functional layer comprises a doping material of the carbon material, wherein an average concentration of the doping material is at least 0.001% at a region of the functional layer.

18. The micromechanical structure according to claim 14 , wherein the functional structure is a membrane structure and wherein the micromechanical structure is part of a sound transducer structure.

19. The micromechanical structure according to claim 14 , wherein the functional structure is a bending beam structure comprising a cantilevered portion and the deflectable functional region.

20. The micromechanical structure according to claim 14 , wherein a first portion of the carbon material comprises an sp 3 hybridization.

21. The micromechanical structure according to claim 14 , wherein a second portion of the carbon material comprises an sp 2 hybridization.

22. A micromechanical sound transducer comprising a micromechanical structure according to claim 14 .

23. The micromechanical structure according to claim 17 , wherein the doping material is one of a metal material, a nitrogen material, a fluorine material, and a phosphorus material.

24. The micromechanical structure according to claim 20 , wherein the first portion is at least 30% of the carbon material.

25. The micromechanical structure according to claim 20 , wherein an average amount of the carbon material comprising the sp 3 hybridization varies along a thickness direction of the functional structure.

26. The micromechanical structure according to claim 20 , wherein an average amount of the carbon material comprising the sp 2 hybridization varies along a thickness direction of the functional structure.

27. The micromechanical structure according to claim 20 , wherein the carbon material essentially comprises an sp 3 hybridization and wherein the base layer arrangement comprises a basis material being carbon essentially comprising an sp 2 hybridization.

28. The micromechanical structure according to claim 21 , wherein the second portion is at least 30% of the carbon material.

29. The micromechanical sound transducer according to claim 22 , wherein the micromechanical sound transducer is a microphone.

30. The micromechanical sound transducer according to claim 22 , wherein the micromechanical sound transdu

Assignees

• Infineon Technologies Ag

Inventors

• Schmid Ulrich
• Frischmuth Tobias
• Irsigler Peter
• Grille Thomas
• Maurer Daniel
• Hedenig Ursula
• Kahn Markus
• Denifl Guenter
• Schneider Michael

Classifications

• B81B2203/0127

  Diaphragms, i.e. structures separating two media that can control the passage from one medium to another; Membranes, i.e. diaphragms with filtering function · CPC title

• B81B2201/0257

  Microphones or microspeakers · CPC title

• H04R2201/003

  Mems transducers or their use · CPC title

• B81C1/00

  Manufacture or treatment of devices or systems in or on a substrate (B81C3/00 takes precedence) · CPC title

• B81C1/00309

  suitable for fluid transfer from the MEMS out of the package or vice versa, e.g. transfer of liquid, gas, sound · CPC title