High-pressure sensor device and method for manufacturing same

• US 20060278002A1
• Filed: 06/14/2006
• Published: 12/14/2006
• Est. Priority Date: 06/14/2005
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Stoetzler, Arno, Henn, Ralf, Jasenek, Axel
• Granted Patent: US 7,802,481 B2
• Time in Patent Office: Days
• US Class Current: 73/706
• CPC Class Codes: G01L 19/0069 from the sensor to its support
• CPC Class Codes: G01L 19/148 Details about the circuit board integration, e.g. integrated with the diaphragm surface or encapsulation
• CPC Class Codes: G01L 9/0055 bonded on a diaphragm

Abstract

A high-pressure sensor device has a pressure sensor element and an electric circuit, in particular in the form of a semiconductor component, the pressure sensor element having a membrane deformable under the effect of pressure, and a functional layer, which experiences a change in its electrical properties when deformed, and which has at least one electric terminal area, and the design and the manufacturing process being simplified in particular by the fact that the semiconductor component is directly connected to the electric terminal area via a solder layer.

Claims

1. A high-pressure sensor device, comprising:

a pressure sensor element;

a solder layer; and

an electric circuit, wherein;

the pressure sensor element includes a membrane deformable under a pressure,

the pressure sensor includes a functional layer that undergoes a change in an electrical property thereof when deformed,

the functional layer includes at least one electric terminal area, and

the electric circuit is directly connected to the electric terminal area via the solder layer.

2. The high-pressure sensor device as recited in claim 1, wherein the functional layer is surface-bonded to the membrane.

3. The high-pressure sensor device as recited in claim 1, further comprising:

an insulation layer provided between the functional layer and the membrane.

4. The high-pressure sensor device as recited in claim 1, wherein:

the electric circuit is connected to two terminal areas of the functional layer via the solder layer, and

at least one elastic molded element for compensating thermal stresses is provided in the electric circuit between the two terminal areas.

5. The high-pressure sensor device as recited in claim 1, wherein the membrane includes steel.

6. The high-pressure sensor device as recited in claim 1, wherein the functional layer includes a piezoelectric material.

7. The high-pressure sensor device as recited in claim 6, wherein the functional layer includes an NiCrSi alloy.

8. The high-pressure sensor device as recited in claim 1, wherein:

the electric circuit in the form of a semiconductor component includes, on its bottom side facing the functional layer, an aluminum plating having an admixture of several percent silicon and copper, which is covered by a nickel layer.

9. The high-pressure sensor device as recited in claim 1, wherein the electric circuit is bonded to the functional layer by an organic bonding compound in at least one area in which no solder layer is provided.

10. The high-pressure sensor device as recited in claim 1, further comprising:

a housing surrounding electric circuit and the pressure sensor element, wherien;

the housing includes an external electric terminal, and

additional electric circuit elements of at least one of the electric circuit and the pressure sensor element are situated in the housing.

12. The high-pressure sensor device as recited in claim 1, wherein the electric circuit includes a semiconductor component.

11. A method for manufacturing a high-pressure sensor device, comprising:

connecting an electric circuit to terminal areas of a functional layer in such a way that solder is first applied to one of two elements; and

then joining and soldering the two elements using a soldering procedure.