MICROMECHANICAL SENSOR AND METHOD FOR MANUFACTURING A MICROMECHANICAL SENSOR

• US 20160033274A1
• Filed: 07/31/2015
• Published: 02/04/2016
• Est. Priority Date: 07/31/2014
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: REINMUTH, Jochen, MAUL, Robert
• Granted Patent: US 10,001,374 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G01C 19/5621 the devices involving a micromechanical structure
• CPC Class Codes: G01C 19/5656 the devices involving a micromechanical structure
• CPC Class Codes: G01C 19/5712 the devices involving a micromechanical structure
• CPC Class Codes: G01C 19/5733 Structural details or topology
• CPC Class Codes: G01C 19/5769 Manufacturing; Mounting; Housings
• CPC Class Codes: G01P 15/125 by capacitive pick-up

Abstract

A micromechanical sensor is provided as including a substrate having a main extension plane and a mass element movable relative to the substrate, the movable mass element being coupled to the substrate via a spring structure, the spring structure including a first and a second spring element, the first and second spring elements extending essentially in parallel to each other in sections and being coupled to each other in sections, the spring structure including a first and a second compensation element for quadrature compensation, the first compensation element being connected to the first spring element, the second compensation element being connected to the second spring element, the first spring element having a first spring structure width extending along a transverse direction, the second spring element having a second spring structure width extending along the transverse direction, the first compensation element in a first subarea extending in parallel to the transverse direction along a first width, the first spring structure width and the first width being different, the second compensation element in a second subarea extending in parallel to the transverse direction along a second width, the second spring structure width and the second width being different.

Claims

1. A micromechanical sensor, comprising:

a substrate having a main extension plane;

a mass element movable relative to the substrate; and

a spring structure via which the movable mass element is coupled to the substrate, wherein;

the spring structure includes a first spring element and a second spring element,

the first and second spring elements extend essentially in parallel to each other in sections,

the spring structure includes a first compensation element and a second compensation element for quadrature compensation,

the first compensation element is connected to the first spring element,

the second compensation element is connected to the second spring element,

the first spring element has a first spring structure width extending along a transverse direction,

the second spring element has a second spring structure width extending along the transverse direction,

the first compensation element in a first subarea extends in parallel to the transverse direction along a first width,

the first spring structure width and the first width are different,

the second compensation element in a second subarea extends in parallel to the transverse direction along a second width, and

the second spring structure width and the second width are different.

2. The micromechanical sensor as recited in claim 1, wherein:

a flank of the first spring element extends along a longitudinal direction toward the substrate,

at least one of;

the first width of the first compensation element and the second width of the second compensation element are essentially equally large when the longitudinal direction and a normal direction are oriented in parallel to each other, the normal direction being oriented essentially perpendicularly to the main extension plane of the substrate, and

the first width of the first compensation element and the second width of the second compensation element are different when the longitudinal direction and the normal direction are not oriented in parallel to each other.

3. The micromechanical sensor as recited in claim 1, wherein:

the first compensation element is connected to the first spring element in such a way that the first compensation element is at least partially situated between the substrate and the first spring element, and

the second compensation element is connected to the second spring element in such a way that the second compensation element is at least partially situated between the substrate and the second spring element.

4. The micromechanical sensor as recited in claim 1, wherein:

a first cross-sectional area of the first spring element and a second cross-sectional area of the second spring element have the same cross-sectional shape.

5. The micromechanical sensor as recited in claim 4, wherein the first spring structure width and the second spring structure width are equally large.

6. The micromechanical sensor as recited in claim 1, wherein:

the first compensation element in a further first subarea extends in parallel to the transverse direction along a further first width,

the second compensation element in a further second subarea extends in parallel to the transverse direction along a further second width, and

at least one of the further first width is greater than the first spring structure width and the further second width is greater than the second spring structure width.

7. The micromechanical sensor as recited in claim 6, wherein the first subarea is primarily situated in an area of the first spring element facing the second spring element, the second subarea being primarily situated in an area of the second spring element facing the first spring element.

8. A method for manufacturing a micromechanical sensor, comprising:

in a first manufacturing step, depositing a first layer on a substrate;

in a second manufacturing step, creating a recess area in the first layer,

in a third manufacturing step, depositing a second layer on the first layer,

in a fourth manufacturing step, structuring the second layer, a spring structure and a mass element being formed of the second layer, the spring structure being configured in such a way that a first spring element and a second spring element of the spring structure extend essentially in parallel to each other in sections;

in a fifth manufacturing step, exposing the mass element and the spring structure, the first layer being at least partially removed, wherein in the fourth manufacturing step, during the structuring of the second layer, a first compensation element and a second compensation element for quadrature compensation are formed in the recess area, so that the first compensation element is connected to the first spring element, and the second compensation element is connected to the second spring element.

9. The method as recited in claim 8, wherein:

the spring structure is configured in such a way that the first spring element has a first spring structure width extending along a transverse direction, and the second spring element has a second spring structure width extending along the transverse direction,

in the fourth manufacturing step the first compensation element is configured in such a way that the first compensation element in a first subarea extends in parallel to the transverse direction along a first width,

the first spring structure width and the first width are different,

in the fourth manufacturing step the second compensation element is configured in such a way that the second compensation element in a second subarea extends in parallel to the transverse direction along a second width, and

the second spring structure width and the second width are different.

10. The method as recited in claim 8, wherein at least one of:

in an area facing the second spring element the first compensation element is connected to the first spring element, and

in an area facing the first spring element the second compensation element is connected to the second spring element.

11. The method as recited in claim 8, wherein:

in the fourth manufacturing step the first spring element is configured in such a way that a flank of the first spring element extends along a longitudinal direction toward the substrate,

a trench angle is enclosed between the longitudinal direction and a normal direction that is essentially perpendicular to a main extension direction of the substrate, and

the spring structure is formed in such a way that at least one of;

at least one of a first width and a further first width of the first compensation element is predefined by the trench angle, and

at least one of a second width and a further second width of the second compensation element is predefined by the trench angle).