Micromechanical component and method for producing a micromechanical component

Patent metadata

Field	Value
Publication number	US-9688527-B2
Application number	US-201414468214-A
Country	US
Kind code	B2
Filing date	Aug 25, 2014
Priority date	Aug 26, 2013
Publication date	Jun 27, 2017
Grant date	Jun 27, 2017

Abstract

A micromechanical component is provided having a substrate having a main plane of extension, a first electrode extending mainly along a first plane in planar fashion, a second electrode extending mainly along a second plane in planar fashion, and a third electrode extending mainly along a third plane in planar fashion, the first, second, and third plane being oriented essentially parallel to the main plane of extension and being situated one over the other at a distance from one another along a normal direction that is essentially perpendicular to the main plane of extension, the micromechanical component having a deflectable mass element, the mass element being capable of being deflected both essentially parallel and also essentially perpendicular to the main plane of extension, the second electrode being connected immovably to the mass element, the second electrode having, in a rest position, a first region of overlap with the first electrode along a projection direction essentially parallel to the normal direction, and having a second region of overlap with the third electrode along a projection direction parallel to the projection direction, the mass element extending in planar fashion mainly along the third plane, the mass element having a recess that extends completely through the mass element, extending in planar fashion along the third plane and parallel to the normal direction, the third electrode being situated at least partly in the recess.

First claim

What is claimed is:

1. A micromechanical component, comprising:
a substrate having a main plane of extension;
a first electrode extending mainly along a first plane in planar fashion;
a second electrode extending mainly along a second plane in planar fashion;
a third electrode extending mainly along a third plane in planar fashion, wherein the first, second, and third planes are oriented essentially parallel to the main plane of extension and are situated one over another at a distance from one another along a normal direction that is essentially perpendicular to the main plane of extension; and
a deflectable mass element capable of being deflected both essentially parallel and also essentially perpendicular to the main plane of extension, wherein:
the second electrode is connected immovably to the mass element,
the second electrode has, in a rest position, a first region of overlap with the first electrode along a projection direction essentially parallel to the normal direction, and having a second region of overlap with the third electrode along a further projection direction parallel to the projection direction,
the mass element extends in planar fashion mainly along the third plane,
the mass element includes a recess that extends completely through the mass element and extends in planar fashion along the third plane and parallel to the normal direction, and
the third electrode is situated at least partly in the recess.

2. The micromechanical component as recited in claim 1 , wherein:
the second electrode has, parallel to the normal direction, a first distance from the first electrode and a second distance from the third electrode, and
the first distance and the second distance are essentially equally large.

3. The micromechanical component as recited in claim 1 , wherein the second electrode is made self-supporting.

4. The micromechanical component as recited in claim 1 , wherein the first region of overlap and the second region of overlap are at least one of:
equally large,
situated alongside one another along the direction of projection parallel to the normal direction, and
mirror-symmetrical relative to an axis of symmetry extending essentially parallel to the second plane.

5. The micromechanical component as recited in claim 1 , further comprising:
a first layer applied on the substrate and including the first electrode;
a second layer applied on the first layer and including the second electrode; and
a third layer applied on the second layer and including the third electrode, the mass element, the recess, and the third electrode being formed one of at least partially and completely from the same third layer.

6. The micromechanical component as recited in claim 1 , wherein:
the first electrode and the third electrode are connected in stationary fashion to the substrate,
the recess has a main direction of extension, and
the third electrode extends in oblong fashion mainly along an electrode direction parallel to the main direction of extension inside the recess.

7. The micromechanical component as recited in claim 1 , further comprising:
a further first electrode; and
a further third electrode, wherein:
the first electrode and the further first electrode are situated alongside one another and electrically insulated from one another along the direction of projection parallel to the normal direction,
the third electrode and further third electrode are situated alongside one another and electrically insulated from one another along the direction of projection parallel to the normal direction, and
the further third electrode extends in oblong fashion mainly along a further electrode direction essentially parallel to the electrode direction inside the recess.

8. The micromechanical component as recited in claim 1 , further comprising:
a detection electrode that extends in planar fashion mainly along the second plane, wherein:
the detection electrode is configured for a capacitive detection of a deflection of the mass element along the normal direction, and
the first electrode is situated at least partly between the detection electrode and the substrate, along the direction of projection parallel to the normal direction.

9. The micromechanical component as recited in claim 5 , wherein:
the third layer has a third layer height extending parallel to the normal direction, and
at least one of the mass element, the recess, and the third electrode extends parallel to the normal direction along a height essentially equal to the third layer height.

10. The micromechanical component as recited in claim 1 , wherein:
the first electrode and the third electrode are quadrature compensation electrodes,
the first electrode is configured to produce a compensating force acting on the second electrode essentially in a direction of the first electrode, and
the third electrode is configured to produce a further compensating force acting on the second electrode essentially in a direction of the third electrode.

11. A method for producing a micromechanical component that includes a substrate having a main plane of extension, comprising:
applying a first layer on the substrate in a first production step;
forming a first electrode in the first layer that extends in planar fashion mainly along a first plane essentially parallel to the main plane of extension;
applying a second layer on the first layer in a second production step;
forming a second electrode in the second layer that extends in planar fashion mainly along a second plane essentially parallel to the first plane;
applying a third layer on the second layer in a third production step;
forming a third electrode one of at least partly and completely in the third layer that extends in planar fashion along a third plane essentially parallel to the second plane;
forming a mass element one of at least partly and completely in the third layer that extends in planar fashion mainly along the third plane essentially parallel to the second plane;
connecting the mass element immovably to the second electrode;
forming a recess in the mass element that extends completely through the mass element along a direction of projection essentially perpendicular to the main plane of extension;
situating the third electrode one of at least partly and completely in the recess of the mass element; and
connecting the third electrode in stationary fashion to the substrate, the second electrode, the mass element, and the third electrode being underetched one of at least partly and completely in a fourth production step.

12. The method as recited in claim 11 , wherein in the third production step the third layer is structured in such a way that the third layer has a third layer height extending parallel to the normal direction, and wherein at least one of the mass element, the recess, and the third electrode extends along a height essentially equal to the layer height.

Assignees

• Bosch Gmbh Robert

Inventors

• Frey Jens
• Reinmuth Jochen

Classifications

• B81B2203/04

  Electrodes · CPC title

• B81B3/0086 Primary

  Electrical characteristics, e.g. reducing driving voltage, improving resistance to peak voltage · CPC title

• G01P3/44

  for measuring angular speed (G01P3/56 takes precedence) · CPC title

• B81B3/0027 Primary

  Structures for transforming mechanical energy, e.g. potential energy of a spring into translation, sound into translation · CPC title

• G01C19/574

  the devices having two sensing masses in anti-phase motion · CPC title