Micromechanical component and manufacturing method for a micromechanical component

Patent metadata

Field	Value
Publication number	US-9156675-B2
Application number	US-201414322106-A
Country	US
Kind code	B2
Filing date	Jul 2, 2014
Priority date	Jul 4, 2013
Publication date	Oct 13, 2015
Grant date	Oct 13, 2015

Abstract

A micromechanical component includes a substrate having a cavern structured into the same, an at least partially conductive diaphragm, which at least partially spans the cavern, and a counter electrode, which is situated on an outer side of the diaphragm oriented away from the substrate so that a clearance is present between the counter electrode and the at least partially conductive diaphragm, the at least partially conductive diaphragm being spanned onto or over at least one electrically insulating material which at least partially covers the functional top side of the substrate, and at least one pressure access being formed on the cavern so that the at least partially conductive diaphragm is bendable into the clearance when a gaseous medium flows from an outer surroundings of the micromechanical component into the cavern. Also described is a manufacturing method for a micromechanical component.

First claim

What is claimed is:

1. A micromechanical component, comprising:
a substrate having a cavern structured into a functional top side of the substrate;
an at least partially conductive diaphragm, which at least partially spans the cavern; and
a counter electrode, which is situated on an outer side of the diaphragm directed away from the substrate so that a clearance is present between the counter electrode and the at least partially conductive diaphragm;
wherein the at least partially conductive diaphragm is spanned onto or over at least one electrically insulating material which at least partially covers the functional top side of the substrate, and
wherein at least one pressure access is formed on the cavern so that the at least partially conductive diaphragm is bendable into the clearance when a gaseous medium flows from an outer surroundings of the micromechanical component into the cavern.

2. The micromechanical component of claim 1 , wherein a plurality of trenches is formed in the substrate so that a bottom surface of the cavern is divided by the plurality of trenches.

3. The micromechanical component of claim 1 , wherein a plurality of depressions is formed on an inner side of the at least partially conductive diaphragm, which is exposed from the cavern.

4. A capacitive sensor device, comprising:
a micromechanical component, including:
a substrate having a cavern structured into a functional top side of the substrate;
an at least partially conductive diaphragm, which at least partially spans the cavern; and
a counter electrode, which is situated on an outer side of the diaphragm directed away from the substrate so that a clearance is present between the counter electrode and the at least partially conductive diaphragm;
wherein the at least partially conductive diaphragm is spanned onto or over at least one electrically insulating material which at least partially covers the functional top side of the substrate, and
wherein at least one pressure access is formed on the cavern so that the at least partially conductive diaphragm is bendable into the clearance when a gaseous medium flows from an outer surroundings of the micromechanical component into the cavern.

5. A microphone, comprising:
a micromechanical component, including:
a substrate having a cavern structured into a functional top side of the substrate;
an at least partially conductive diaphragm, which at least partially spans the cavern; and
a counter electrode, which is situated on an outer side of the diaphragm directed away from the substrate so that a clearance is present between the counter electrode and the at least partially conductive diaphragm;
wherein the at least partially conductive diaphragm is spanned onto or over at least one electrically insulating material which at least partially covers the functional top side of the substrate, and
wherein at least one pressure access is formed on the cavern so that the at least partially conductive diaphragm is bendable into the clearance when a gaseous medium flows from an outer surroundings of the micromechanical component into the cavern.

6. A manufacturing method for a micromechanical component, the method comprising:
forming an at least partially conductive diaphragm, with the aid of which a cavern which is structured into a functional top side of a substrate is at least partially spanned; and
forming a counter electrode, which is situated on an outer side of the diaphragm directed away from the substrate, a clearance being formed between the counter electrode and the at least partially conductive diaphragm;
wherein the at least partially conductive diaphragm is spanned onto or over at least one electrically insulating material which at least partially covers the top side of the substrate, and
wherein at least one pressure access is formed on the cavern so that the at least partially conductive diaphragm is bent into the clearance when a gaseous medium flows from an outer surroundings of the micromechanical component into the cavern.

7. The manufacturing method of claim 6 , wherein, prior to forming the at least partially conductive diaphragm, the cavern is filled at least partially with at least one sacrificial material on top of which at least one material of an inner side of the at least partially conductive diaphragm is deposited, the sacrificial material being etched away via at least one etch access formed spaced apart from the diaphragm.

8. The manufacturing method of claim 7 , wherein, prior to forming the at least partially conductive diaphragm, the cavern is filled only partially with the at least one sacrificial material so that at least one first cavity is formed which is covered by the at least one sacrificial material, at least one of the at least one electrically insulating material and the at least one material of the inner side of the at least partially conductive diaphragm.

9. The manufacturing method of claim 8 , wherein the at least one first cavity is formed in a plurality of trenches in the substrate, which divide a bottom surface of the cavern.

10. The manufacturing method of claim 7 , wherein, adjoining the sacrificial material which is later etched away and/or adjoining the at least one electrically insulating material, at least one second cavity is formed in a plurality of depressions on the inner side of the diaphragm.

11. The manufacturing method of claim 10 , wherein the at least one material of the inner side of the at least partially conductive diaphragm is deposited as an LPCVD layer, into which continuous recesses for establishing positions of the depressions later formed therein are structured, the diaphragm being reinforced with the aid of an epitaxial growth process forming the depressions having the at least one second cavity present therein.

12. A manufacturing method for a sensor device, the method comprising:
situating a micromechanical component at least one of in and on a sensor arrangement;
wherein the micromechanical component includes:
a substrate having a cavern structured into a functional top side of the substrate;
an at least partially conductive diaphragm, which at least partially spans the cavern; and
a counter electrode, which is situated on an outer side of the diaphragm directed away from the substrate so that a clearance is present between the counter electrode and the at least partially conductive diaphragm;
wherein the at least partially conductive diaphragm is spanned onto or over at least one electrically insulating material which at least partially covers the functional top side of the substrate, and
wherein at least one pressure access is formed on the cavern so that the at least partially conductive diaphragm is bendable into the clearance when a gaseous medium flows from an outer surroundings of the micromechanical component into the cavern.

13. A manufacturing method for a microphone, the method comprising:
situating a micromechanical component at least one of in and on a microphone arrangement;
wherein the micromechanical component includes:
a substrate having a cavern structured into a functional top side of the substrate;
an at least partially conductive diaphragm, which at least partially spans the cavern; and
a counter electrode, which is situated on an outer side of the diaphragm directed away from the substrate so that a clearance is present between the counter electrode and the at least partially conductive diaphragm;
wherein the at least partially conductive diaphragm is spanned onto or over at least one electrically insulating material which at least partially covers the functional top side of the substrate, and
wherein at leas

Assignees

• Kaelberer Arnd
• Reinmuth Jochen
• Classen Johannes
• Bosch Gmbh Robert

Inventors

• Kaelberer Arnd
• Reinmuth Jochen
• Classen Johannes

Classifications

• B81B2201/0257

  Microphones or microspeakers · CPC title

• H04R31/00

  Apparatus or processes specially adapted for the manufacture of transducers or diaphragms therefor {(manufacture of microstructural arrangements of deformable or non-deformable structures in general B81C1/00182)} · CPC title

• B81B2207/012

  the micromechanical device and the control or processing electronics being separate parts in the same package · CPC title

• B81C1/00682

  Treatments for improving mechanical properties, not provided for in B81C1/00658 - B81C1/0065 · CPC title

• 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