Patent ID: 10330549

Abstract:
A pressure measurement cell, comprising: a ceramic measurement membrane and a ceramic counterpart. The measurement membrane is joined to the counterpart in a pressure-tight manner forming a pressure chamber between the measurement membrane and the counterpart by means of an active brazing solder. The pressure measurement cell furthermore has a solder stop layer on a surface of the measurement membrane and/or the counterpart, wherein the solder stop layer has a metal oxide or a reduced form of the metal oxide. The metal oxide has at least one oxidation stage, which, assuming an activity coefficient of Rakt=1 at an inverse temperature of 8·10−4/K, 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) and which, assuming an activity coefficient of Rakt=1, at an inverse temperature of 9·10−4/K has 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). Suitable metal oxides are, for example, oxides of chromium, tungsten or titanium.