Patent ID: 8018234

Claim:
Vacuum pressure measuring device having a vacuum volume, the device comprising: an electron source ( 1 ) for generating electrons; a reaction zone ( 30 ) for the formation of ions ( 22 ) through impact ionization, the electron source ( 1 ) communicating with the reaction zone ( 30 ) via a passage opening ( 40 ) for the electrons ( 21 ); the electron source ( 1 ) including an insulating housing ( 6 ) having a insulating wall encompassing a vacuum volume ( 7 ) containing a vacuum condition, the wall having a membrane carrier ( 4 ); a nanomembrane ( 5 ) supported by the membrane carrier ( 4 ) across the passage opening ( 40 ) and separating the vacuum volume ( 7 ) from the reaction zone ( 30 ) and from an outside region outside the housing ( 6 ) such that the vacuum volume ( 7 ) is gas-tight with respect to the reaction zone ( 30 ) and with respect to the outside region, the nanomembrane ( 5 ) being at least partly permeable to electrons; a cathode ( 2 ) in the vacuum volume ( 7 ) for the emission the electrons ( 21 ); and an anode configuration ( 3 ) in the proximity of the nanomembrane ( 5 ) and operating so that electrons ( 21 ) are conducted toward the nanomembrane ( 5 ) and at least some of the electrons penetrate the nanomembrane ( 5 ), the nanomembrane ( 5 ) bordering the vacuum volume of the vacuum pressure measuring device.