Method for manufacturing a connection between two ceramic parts, especially parts of a pressure sensor, and a ceramic product, especially a ceramic pressure sensor

• US 9,136,662 B2
• Filed: 10/28/2011
• Issued: 09/15/2015
• Est. Priority Date: 10/29/2010
• Status: Active Grant

• Current Assignee: Endress + Hauser GmbH + Company KG (Endress+Hauser AG)
• Original Assignee: Endress + Hauser GmbH + Company KG (Endress+Hauser AG)
• Inventors: Rossberg, Andreas, Philipps, Michael, Hegner, Frank, Drewes, Ulfert, Muller, Jorg, Doms, Marco
• Primary Examiner(s): Caputo, Lisa
• Assistant Examiner(s): DUNLAP, JONATHAN M
• Application Number:
  US13/881,533
• Publication Number:
  US 20130213138A1
• Time in Patent Office: 1,418 Days
• Field of Search: 737/00, 737/18, 228/121, 228/124.5, 228/262.75
• US Class Current: 1/1
• CPC Class Codes: B23K 1/0008 specially adapted for particular articles or work
• CPC Class Codes: B23K 1/008 Soldering within a furnace B23K1/012 takes precedence
• CPC Class Codes: B23K 1/19 taking account of the properties of the materials to be soldered
• CPC Class Codes: B23K 35/0222 for use in soldering, brazing B23K35/0205 takes precedence
• CPC Class Codes: B23K 35/32 with the principal constituent melting at more than 1550 degrees C
• CPC Class Codes: C04B 2235/6581 Total pressure below 1 atmosphere, e.g. vacuum
• CPC Class Codes: C04B 2235/72 Products characterised by the absence or the low content of specific components, e.g. alkali metal free alumina ceramics
• CPC Class Codes: C04B 2237/122 based on refractory metals
• CPC Class Codes: C04B 2237/127 The active component for bonding being a refractory metal
• CPC Class Codes: C04B 2237/128 The active component for bonding being silicon
• CPC Class Codes: C04B 2237/343 Alumina or aluminates
• CPC Class Codes: C04B 2237/592 whereby the interlayer is not continuous, e.g. not the whole surface of the smallest substrate is covered by the interlayer
• CPC Class Codes: C04B 2237/60 Forming at the joining interface or in the joining layer specific reaction phases or zones, e.g. diffusion of reactive species from the interlayer to the substrate or from a substrate to the joining interface, carbide forming at the joining interface
• CPC Class Codes: C04B 2237/708 of one or more of the interlayers
• CPC Class Codes: C04B 37/006 consisting of metals or metal salts
• 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 9/0075 using a ceramic diaphragm, e.g. alumina, fused quartz, glass
• CPC Class Codes: H01R 43/0235 for applying solder H01R43/0228 takes precedence

Abstract

A method for manufacturing a connection between two ceramic parts comprises: providing a first ceramic part and a second ceramic part; providing an active hard solder, or active braze, on at least one surface section of at least one of the ceramic parts; and heating the active hard solder, or active braze, in a vacuum soldering, brazing process. The entire active hard solder, or active braze, for connecting the first and second ceramic parts is provided in such a manner that at least one surface section of at least one of the ceramic parts, preferably both ceramic parts, is coated by means of gas phase deposition of the alloy of the active hard solder, or active braze.

Claims

1. A method for manufacturing a connection between two ceramic parts, comprising the steps of:

providing a first ceramic part and a second ceramic part;

providing an active hard solder, or active braze, on at least one surface section of at least one of the ceramic parts; and

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

the entire active hard solder, or active braze, for connecting the first and second ceramic parts is provided in such a manner that at least one surface section of at least one of the ceramic parts, preferably both ceramic parts, is coated by means of gas phase deposition of the alloy of the active hard solder, or active braze, and/or its components,

the gas phase deposition comprises a sputtering process or thermal evaporating, in order to transfer the components of the active hard solder, or active braze, into the gas phase,

the active hard solder, or active braze, has a plurality of components, and wherein, in the sputter process, a sputter target is used, which contains the components of the active hard solder, or active braze,

the active hard solder, or active braze, has a desired composition, in which components Ki of the active hard solder, or active braze, are present in a weight percent ci, and in the case of which the difference between the coefficient of thermal expansion of the active hard solder, or active braze, and the coefficient of thermal expansion of the material of the ceramic parts has a minimum, wherein the sputter target contains the components of the active hard solder, or active braze, in proportions ci, target, which have relative deviations di of the individual components from the desired composition ci, desired, as follows;

di;

=|(ci, target−

ci, desired)/ci, desired|

wherein di<

4%, preferably no more than 2% and especially preferably no more than 1%.

2. The method as claimed in claim 1, wherein:

the at least one surface section of the at least one ceramic part is coated by means of gas phase deposition, first of all, only with at least one active component of the active hard solder, or active braze.

3. Method as claimed in claim 2, wherein:

the coating with the at least one active component has a thickness of not less than 10 nm, especially not less than 40 nm, and preferably not less than 80 nm.

4. The method as claimed in claim 2, wherein:

the coating with the at least one active component has a thickness of no more than 400 nm, especially no more than 300 nm, and preferably no more than 200 nm.

5. The method as claimed in claim 2, wherein:

the at least one active component for gas phase deposition is brought into the gas phase by means of a sputter process; and

in the sputter process a sputter target is used, which contains only the at least one active component.

6. The method as claimed in claim 1, wherein:

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

7. The method as claimed in claim 1, wherein:

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

Ni—

Ti alloy, and wherein the at least one active component comprises Ti or Zr.

8. The method as claimed in claim 1, wherein:

the concentrations of the components of the active hard solder, or active braze, in the desired composition are as follows;

55<

c_Zr<

65.5, 20.5<

c_Ni<

27.5 and 14<

c_Ti<

17.5, especially 61<

c_Zr<

63.5, 21.5<

c_Ni<

24 and 14.5<

c_Ti<

15.5.

9. The method as claimed in claim 1, wherein:

the first ceramic part and the second ceramic part are pressure-tightly connected along an annular joint, which surrounds a hollow space between the first ceramic part and the second ceramic part;

the active hard solder, or active braze, is deposited on at least one annular surface section of a ceramic part; and

a region surrounded by the annular surface section is masked during deposition of the active hard solder, or active braze.

10. A ceramic product, obtainable according to the method defined in claim 1, the ceramic product, comprises:

a first ceramic part; and

a second ceramic part, said first and said second ceramic parts are joined by means of a joint, which comprises an active hard solder, or active braze, wherein;

said active hard solder, or active braze, in said joint has a thickness of no more than 20 μ

m, especially no more than 17 μ

m, preferably no more than 14 μ

m and especially preferably no more than 12 μ

m.

11. The ceramic product as claimed in claim 10, wherein:

the ceramic parts comprise corundum; and

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

Ni—

Ti alloy.

12. The ceramic product as claimed in claim 10, wherein:

the product is a pressure sensor;

said first ceramic part comprises a platform of the pressure sensor, said second ceramic part comprises said measuring membrane of the pressure sensor; and

said measuring membrane is connected pressure-tightly with the platform along an annular joint, which comprises the active hard solder, or active braze.