Ceramic pressure measurement cell and method for production thereof

A pressure measurement cell, comprising:

• a ceramic measurement membrane;
• and
• a ceramic counterpart;
• and
• an active solder stop layer, wherein:
• said measurement membrane is joined pressure-tight with said counterpart, forming a pressure chamber between said measurement membrane and said counterpart by means of an active brazing solder;
• said solder stop layer is on a surface of said measurement membrane and/or said counterpart, which layer prevents the active brazing solder from inwardly radially entering said pressure chamber via said solder stop layer when said measurement membrane is joined with said counterpart;
• said solder stop layer comprises a metal oxide or a reduced form of the metal oxide, said metal oxide comprises at least one oxidation step, which has an oxygen coexistence decomposition pressure of not less than 1−23 MPa (10−23· bar) and not more than 1−12 MPa (10−12· bar) at an inverse temperature of 8·10−4/K assuming an activity coefficient of Rakt=1 and an oxygen coexistence decomposition pressure of not less than 1−27 MPa (10−27 bar) and not more than 1−15 MPa (10−15 bar) bar at an inverse temperature of 9·10−4/K, assuming an activity coefficient of Rakt=1.

A method of bonding two ceramic components using an active brazing solder, comprising:

• providing the two ceramic components;
• preparing a solder stop layer on at least one surface of at least one ceramic component, which separates a portion of the surface to be wetted by the solder from a portion to be kept free of the solder;
• providing the active brazing solder between the first and the second ceramic component in the surface areas of the first and of the second component to be wetted by the active brazing solder;
• heating the ceramic components and the active brazing solder under vacuum up to a temperature at which the active brazing solder melts and reacts with the ceramic components;
• and
• allowing the ceramic components to cool down, wherein:
• the solder stop layer comprises a metal oxide, which has an oxygen coexistence decomposition pressure of not less than 1−23 MPa (10−23· bar) and not more than 1−12 MPa (10−12· bar) at an inverse temperature of 8·10−4/K and an oxygen coexistence decomposition pressure of not less than 1−27 MPa (1027 bar) and not more than 1−15 MPa (10−15 bar) at an inverse temperature of 9.10−4/K.