METHOD FOR PRODUCING A VACUUM MEASURING CELL OF THE MEMBRANE TYPE
First Claim
1. Method for the production of a vacuum measuring cell (8) with a diaphragm (2) as pressure transducer, wherein on the one side of the diaphragm (2) spaced apart is disposed a first housing plate (1) in the margin region with a joining means (3) forming a seal, such that between them a reference vacuum chamber (7) is formed, and that on the other side of the diaphragm (2) spaced apart a second housing plate (4) is disposed in the margin region with a joining means (3) forming a seal, such that between them a measuring vacuum chamber (9) is formed, and that the second housing plate (4) includes an opening and, communicating with such opening and the measuring vacuum chamber (9), connection means (5) with joining means (6) are disposed forming a seal for the joining of the measuring vacuum chamber (9) with the medium to be measured, wherein at least the diaphragm (2) and the two housing plates (1, 4) are realized as ceramic parts (1, 2, 4) of an aluminum oxide, characterized in that for at least one of the joining means (3, 6) aluminum with a thickness in the range from 0.5 μ
- m to 30 μ
m is disposed in the joining region between the ceramic parts (1, 2, 4) to be joined, and that the ceramic parts (1, 2, 4) to be joined are pressed together at increased temperature in the range from 600°
C. to 680°
C. in a process gas atmosphere encompassing the parts, which atmosphere includes a reducing gas, during a time in the range from 30 to 90 minutes, and that subsequently a tempering step is carried out in a second process gas atmosphere which includes oxygen, wherein the tempering takes place in a temperature range from 450°
C. to 575°
C. such that the metallic aluminum is substantially oxidized to aluminum oxide.
3 Assignments
0 Petitions
Accused Products
Abstract
Method for producing a vacuum measuring cell having a pressure transducer diaphragm with housing plates sealed on opposite sides to form reference and measuring vacuum chambers. An opening in one plate communicates with the measuring vacuum chamber and has a sealed connection for joining to medium to be measured. The diaphragm and plates are aluminum oxide ceramic and at least one of the seals is aluminum with a thickness of 0.5 μm to 30 μm. The ceramic parts are pressed together at increased temperature of 600° C. to 680° C. in a process gas atmosphere including a reducing gas, during a time of 30 to 90 minutes, and subsequently a tempering step is carried out in a second process gas atmosphere including oxygen, tempering taking place at a temperature of 450° C. to 575° C. such that the metallic aluminum is oxidized into aluminum oxide.
-
Citations
17 Claims
-
1. Method for the production of a vacuum measuring cell (8) with a diaphragm (2) as pressure transducer, wherein on the one side of the diaphragm (2) spaced apart is disposed a first housing plate (1) in the margin region with a joining means (3) forming a seal, such that between them a reference vacuum chamber (7) is formed, and that on the other side of the diaphragm (2) spaced apart a second housing plate (4) is disposed in the margin region with a joining means (3) forming a seal, such that between them a measuring vacuum chamber (9) is formed, and that the second housing plate (4) includes an opening and, communicating with such opening and the measuring vacuum chamber (9), connection means (5) with joining means (6) are disposed forming a seal for the joining of the measuring vacuum chamber (9) with the medium to be measured, wherein at least the diaphragm (2) and the two housing plates (1, 4) are realized as ceramic parts (1, 2, 4) of an aluminum oxide, characterized in that for at least one of the joining means (3, 6) aluminum with a thickness in the range from 0.5 μ
- m to 30 μ
m is disposed in the joining region between the ceramic parts (1, 2, 4) to be joined, and that the ceramic parts (1, 2, 4) to be joined are pressed together at increased temperature in the range from 600°
C. to 680°
C. in a process gas atmosphere encompassing the parts, which atmosphere includes a reducing gas, during a time in the range from 30 to 90 minutes, and that subsequently a tempering step is carried out in a second process gas atmosphere which includes oxygen, wherein the tempering takes place in a temperature range from 450°
C. to 575°
C. such that the metallic aluminum is substantially oxidized to aluminum oxide. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17)
- m to 30 μ
Specification