Pressure Sensor and Method for its Manufacture

• US 20130263670A1
• Filed: 11/23/2011
• Published: 10/10/2013
• Est. Priority Date: 12/14/2010
• Status: Active Grant

• Current Assignee: Endress + Hauser GmbH + Company KG (Endress+Hauser AG)
• Original Assignee: Endress + Hauser GmbH + Company KG (Endress+Hauser AG)
• Inventors: Selders, Peter, Rossberg, Andreas, Schmidt, Elke, Berlinger, Andrea
• Granted Patent: US 9,459,169 B2
• Time in Patent Office: Days
• US Class Current: 73/700
• CPC Class Codes: B23K 31/02 relating to soldering or welding dip or wave soldering in the manufacture of printed circuits H05K3/34
• CPC Class Codes: G01L 7/00 Measuring the steady or quasi-steady pressure of a fluid or a fluent solid material by mechanical or fluid pressure-sensitive elements G01L11/004 takes precedence; transmitting or indicating the displacement of mechanical pressure-sensitive elements by electric , e.g., photoelectric or magnetic means G01L9/00; measuring differences of two or more pressure values G01L13/00; measuring two or more pressure values simultaneously G01L15/00
• CPC Class Codes: G01L 9/0044 Constructional details of non-semiconductive diaphragms
• CPC Class Codes: G01L 9/0075 using a ceramic diaphragm, e.g. alumina, fused quartz, glass

Abstract

A method for manufacturing a pressure sensor, comprising: providing a ceramic platform, a ceramic measuring membrane, and an intermediate ring; providing an active braze material by means of gas phase deposition at least on a first surface section of a first surface and on a second surface section of a second surface. The first surface is a platform surface, which is to be connected with the intermediate ring by means of the active hard solder, or braze, or a surface of the intermediate ring, which is to be connected with the platform by means of the active hard solder, or braze. The second surface is a measuring membrane surface, which is to be connected with the intermediate ring by means of the active hard solder, or braze, or a surface of the intermediate ring, which is to be connected with the measuring membrane by means of the active hard solder, or braze. The intermediate ring is positioned between the measuring membrane and the platform; the active hard solder, or braze, is heated in a soldering, or brazing, process, wherein the intermediate ring remains essentially solid during the soldering, or brazing, process.

Claims

1-16. -16. (canceled)

17. A method for manufacturing a pressure sensor, comprising the steps of:

providing a ceramic platform, a ceramic measuring membrane, and an intermediate ring;

providing an active hard solder or braze material by means of gas phase deposition at least on a first surface section of a first surface and on a second surface section of a second surface; and

heating the active hard solder, or braze, in a soldering, or brazing, process, wherein;

the first surface is a platform surface, which is to be connected with the intermediate ring by means of the active hard solder, or braze, or a surface of the intermediate ring, which is to be connected with the platform by means of the active hard solder, or braze;

the second surface is a measuring membrane surface, which is to be connected with the intermediate ring by means of the active hard solder, or braze, or a surface of the intermediate ring, which is to be connected with the measuring membrane by means of the active hard solder, or braze;

positioning the intermediate ring between the measuring membrane and the platform; and

wherein;

the intermediate ring remains essentially solid during the soldering, or brazing, process.

18. The method as claimed in claim 17, wherein:

said soldering, or brazing, process is a vacuum soldering, or brazing, process or a soldering, or brazing, process under protective gas.

19. The method as claimed in claim 17, wherein:

the intermediate ring comprises a metal material, especially W, MoTiZr or MoCu.

20. The method as claimed in claim 17, wherein:

the intermediate ring comprises a ceramic material, especially corundum.

21. The method as claimed in claim 17, wherein:

the intermediate ring has a thickness of not less than 10 μ

m.

22. The method as claimed in claim 17, wherein:

the intermediate ring has a thickness of no more than 60 μ

m, especially no more than 45 μ

m, preferably no more than 30 and especially preferably no more than 25 μ

m.

23. The method as claimed in claim 17, wherein:

the thickness of the active braze material provided by means of gas phase deposition on a surface section amounts to not less than 0.05 μ

m, preferably not less than 0.1 μ

m.

24. The method as claimed in claim 17, wherein:

the providing of the active hard solder, or braze, occurs by means of gas phase deposition in such a manner that the active hard solder, or braze, is provided by means of gas phase deposition on both surface sections of the platform, respectively the measuring membrane, to be joined with the intermediate ring and on at least one surface of the intermediate ring, preferably on both surfaces of the intermediate ring.

25. The method as claimed in claim 17, wherein:

providing of the active hard solder, or braze, by means of gas phase deposition occurs in such a manner that the active hard solder, or braze, is provided by means of gas phase deposition on both surfaces of the intermediate ring to be joined and on at least one of the sections of the platform, respectively the measuring membrane, to be joined with the intermediate ring surface, preferably on both surface sections, that of of the platform and that of the measuring membrane.

26. The method as claimed in claim 17, wherein:

providing of the active braze material by means of gas phase deposition occurs in such a manner that at least one ceramic surface, respectively one ceramic surface section, is coated at least with an active component of the active hard solder, or braze.

27. The method as claimed in claim 26, wherein:

on the layer of the active component, a mixture of all components of the active solder is deposited, in order to provide a solderable, or brazable, active hard solder, or braze; and

/or

a mixture of all components of the active hard solder, or braze, is provided on a surface, respectively a surface section, which is to be joined with the ceramic surface, respectively the ceramic surface section, on which the active component was deposited.

28. The method as claimed in claim 17, wherein:

the intermediate ring is a metal intermediate ring, wherein a bonding promoter, especially Ti, is deposited on the intermediate ring.

29. A pressure sensor, comprising:

a ceramic platform;

a ceramic measuring membrane; and

an intermediate ring, which is arranged between said platform and said measuring membrane, wherein;

said platform is connected with said intermediate ring by means of a first joint, and said intermediate ring is connected with the measuring membrane by means of a second joint; and

said first and second joints comprise, in each case, an active hard solder, or braze.

30. The pressure sensor as claimed in claim 29, wherein:

said measuring membrane and/or said platform comprise corundum; and

said active hard solder, or braze, comprises a Zr—

Ni—

Ti alloy.

31. The pressure sensor as claimed in claim 29, wherein:

said intermediate ring comprises a metal material, especially W, MoTiZr, MoCu, or a ceramic material, especially corundum.

32. The pressure sensor as claimed in claim 29, wherein:

said intermediate ring has a thickness of no more than 60 μ

m, especially no more than 45 μ

m, preferably no more than 30 and especially preferably no more than 20 μ

m.