Pressure sensor system

Patent metadata

Field	Value
Publication number	US-9909946-B2
Application number	US-201615379018-A
Country	US
Kind code	B2
Filing date	Dec 14, 2016
Priority date	Feb 21, 2013
Publication date	Mar 6, 2018
Grant date	Mar 6, 2018

Abstract

A pressure sensor system having a pressure sensor chip is specified. The pressure sensor chip is mounted on a mounting receptacle of a ceramic housing body having a pressure feed guided to the pressure sensor chip. The housing body is three-dimensionally shaped and monolithically formed and is formed by a ceramic material having a coefficient of thermal expansion which deviates by less than 30% from the coefficient of thermal expansion of the pressure sensor chip in a temperature range of greater than or equal to −40° C. and less than or equal to 150° C.

First claim

What is claimed is:

1. A pressure sensor system comprising:
a pressure sensor chip mounted on a mounting receptacle of a housing body comprising a ceramic material, the housing body having a pressure fitting and a pressure feed guided to the pressure sensor chip, the pressure feed extending from the pressure fitting up to the pressure sensor chip,
wherein the housing body comprises a non-planar three-dimensional surface topography on a mounting side on which the sensor chip is mounted,
wherein the housing body is a monolithic structure such that the pressure fitting comprising the ceramic material and the pressure feed comprising the ceramic material are part of the monolithic structure, wherein a coefficient of thermal expansion of the housing body deviates by less than 30% from the coefficient of thermal expansion of the pressure sensor chip in a temperature range of greater than or equal to −40° C. and less than or equal to 150° C.,
wherein the pressure fitting is cylindrical or conical, wherein the pressure feed comprises a through opening in the housing body that extends from a first end to an opposite second end, wherein the second end of the through opening is an opening in the mounting receptacle, wherein a cross-sectional dimension of the through opening at the first end is larger than a cross-sectional dimension of the through opening at the second end, and
wherein the pressure feed, leading toward the pressure sensor chip, is undercut-free.

2. The pressure sensor system according to claim 1 , wherein the pressure fitting has a round cross-section.

3. The pressure sensor system according to claim 1 , wherein the pressure fitting has a groove on a side facing the pressure sensor, the groove surrounding the pressure feed.

4. The pressure sensor system according to claim 1 , wherein the pressure sensor chip is based on silicon.

5. The pressure sensor system according to claim 1 , wherein the ceramic material comprises mullite.

6. The pressure sensor system according to claim 1 , wherein the ceramic material comprises aluminum oxide, zirconium oxide, aluminum nitride, silicon carbide, and/or silicon nitride.

7. The pressure sensor system according to claim 1 , the ceramic material consists of one or more selected from mullite, aluminum nitride, silicon carbide, and/or silicon nitride.

8. The pressure sensor system according to claim 1 , wherein the coefficients of thermal expansion of the housing body and the pressure sensor chip deviate by less than 10% from one another in a temperature range of greater than or equal to −50° C. and less than or equal to 200° C.

9. The pressure sensor system according to claim 1 , wherein the mounting receptacle is formed by a protrusion or a depression of the housing body and the pressure feed opens into the mounting receptacle.

10. The pressure sensor system according to claim 1 , wherein a signal processing chip is mounted on a further mounting receptacle of the housing body.

11. The pressure sensor system according to claim 1 , wherein the pressure sensor chip is mounted by a rigid connecting material directly on the mounting receptacle formed by a glass solder, a metallic solder, or an epoxy resin adhesive.

12. The pressure sensor system according to claim 1 , wherein the housing body is three-dimensionally shaped and monolithically formed by a ceramic injection molding method.

13. The pressure sensor system according to claim 1 , wherein the pressure sensor system comprises electrical connections on the housing body for electrical connection of at least the pressure sensor chip, which comprise one or more of the following elements: wiring carrier, conductor tracks, and bond wires.

14. The pressure sensor system according to claim 1 , wherein the pressure sensor chip is electrically contacted by bond wire connections covered with a polymer potting.

15. The pressure sensor system according to claim 1 , wherein the pressure sensor system comprises a cover fastened on the housing body above the pressure sensor chip.

16. The pressure sensor system according to claim 15 , wherein the cover is fastened on the housing body by a mechanical lock.

17. A method of forming a pressure sensor system, the method comprising:
providing a pressure sensor chip;
using a ceramic injection molding method, forming a housing body having a monolithical structure and comprising a non-planar three-dimensional surface topography on a mounting side; and
mounting the pressure sensor chip over the mounting side of the housing body, the housing body having a pressure fitting and a pressure feed guided to the pressure sensor chip such that the pressure fitting comprising a ceramic material and the pressure feed comprising the ceramic material are part of the monolithic structure, the pressure feed extending from the pressure fitting up to the pressure sensor chip, wherein the pressure fitting is cylindrical or conical, wherein the pressure feed comprises a through opening in the housing body that extends from a first end to an opposite second end, wherein the second end of the through opening is an opening in the mounting side, wherein a cross-sectional dimension of the through opening at the first end is larger than a cross-sectional dimension of the through opening at the second end, wherein the pressure feed, leading toward the pressure sensor chip, is undercut-free, and
wherein a coefficient of thermal expansion of the housing body deviates by less than 30% from the coefficient of thermal expansion of the pressure sensor chip in a temperature range of greater than or equal to −40° C. and less than or equal to 150° C.

18. The method of claim 17 , wherein forming the housing body comprises sintering at 1500° C. to 1750° C. in air.

19. The method of claim 17 , wherein forming the housing body comprises fixing a cover on the housing body above the sensor chip.

20. The method of claim 19 , wherein the cover is fastened on the housing by a mechanical lock.

21. A pressure sensor system comprising:
a pressure sensor chip mounted on a mounting receptacle of a housing body comprising a ceramic material, the housing body having a pressure fitting and a pressure feed guided to the pressure sensor chip such that the pressure fitting comprising the ceramic material and the pressure feed comprising the ceramic material are part of a monolithic structure, the pressure feed extending from the pressure fitting up to the pressure sensor chip,
wherein the mounting receptacle comprises a depression in the housing body,
wherein the pressure feed comprises a through opening in the housing body that extends from a first end to an opposite second end, wherein the second end of the through opening is an opening in the mounting receptacle, wherein a cross-sectional dimension of the through opening at the first end is larger than a cross-sectional dimension of the through opening at the second end, wherein the through opening comprises a first section comprising parallel sidewall and a second section comprising tapered sidewalls, wherein the second section comprises a first cross-sectional dimension at an end towards the first end and a second cross-sectional dimension at an opposite end towards the second end, wherein the second cross-sectional dimension is smaller than the first cross-sectional dimension.

Assignees

• Epcos Ag

Inventors

• Ihle Jan
• Peschka Andreas
• Hundertmark Bert
• Bohl Benjamin
• Ostrick Bernhard

Classifications

• C04B2235/3463

  Alumino-silicates other than clay, e.g. mullite · CPC title

• C04B35/185

  Mullite {3Al2O3-2SiO2} · CPC title

• G01L19/04 Primary

  Means for compensating for effects of changes of temperature {, i.e. other than electric compensation} · CPC title

• G01L19/0084

  to the outside of the housing (other details about the housing see G01L19/14) · CPC title

• C04B2235/6022

  Injection moulding · CPC title