Abstract: A vacuum pressure measuring device with an electron source has a reaction zone for forming ions by impact ionization, wherein the electron source communicates with the reaction zone via a passage for the electrons. The electron source is surrounded by an insulating housing with a vacuum chamber, and a partition part is designed as a membrane carrier, carrying a nanomembrane at least in one section, the membrane separating the vacuum chamber from the outer region in a gastight manner and being at least partially designed to be electron-permeable. The vacuum chamber has a cathode for the emission of electrons. In the region of and/or on the nanomembrane, an anode arrangement is provided such that electrons are conducted against the nanomembrane and at least partially through it. The nanomembrane abuts the vacuum chamber of the vacuum pressure measuring device.

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 ?m to 30 ?m. 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.

Abstract: A vacuum measuring cell with a membrane between two planar housing parts has a first housing part forming a reference vacuum volume and the second housing part forming a measuring vacuum volume with a connection for the medium to be measured and a mechanism for measuring the membrane deflection. The membrane surface exposed to the medium to be measured is a structured surface.

Abstract: A cathode configuration for emission of electrons has a reaction zone connected to an entrance opening for the supply of neutral particles. The opening communicates with the cathode configuration for the ionization of the neutral particles and an ion extraction system communicates with the reaction zone. Ions from the extraction system are sent to a detection system and a mechanism for the evacuation of the mass spectrometer arrangement. The cathode configuration includes a field emission cathode with an emitter surface, wherein at a short distance from this emitter surface, an extraction grid is disposed for the extraction of electrons, which grid substantially covers the emitter surface. The emitter surface encompasses herein at least partially a hollow volume such that a tubular structure is formed.

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 ?m to 30 ?m. 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.

Abstract: A pressure measuring cell has a first housing body and a membrane arranged proximate the housing body, both of ceramic. The membrane has a peripheral edge joined to the first housing body to create a reference pressure chamber. A second housing body made of ceramic material is opposite the membrane and is joined to the peripheral edge of the membrane, the second housing body together with the membrane forming a measurement pressure chamber. The second housing body has a port for connecting the pressure measuring cell to a medium to be measured. The first housing body, the second housing body and the membrane are tightly connected along the peripheral edge of the membrane in a central area of the first housing body a hole is formed, reaching through the first housing body and at least in the central region of the membrane and opposite the hole a surface of the membrane is formed as a first optically reflective area.

Abstract: A vacuum pressure measuring device with an electron source has a reaction zone for forming ions by impact ionization, wherein the electron source communicates with the reaction zone via a passage for the electrons. The electron source is surrounded by an insulating housing with a vacuum chamber, and a partition part is designed as a membrane carrier, carrying a nanomembrane at least in one section, the membrane separating the vacuum chamber from the outer region in a gastight manner and being at least partially designed to be electron-permeable. The vacuum chamber has a cathode for the emission of electrons. In the region of and/or on the nanomembrane, an anode arrangement is provided such that electrons are conducted against the nanomembrane and at least partially through it. The nanomembrane abuts the vacuum chamber of the vacuum pressure measuring device.

Abstract: A pressure measuring cell has a first housing body and a membrane arranged proximate the housing body, both of ceramic. The membrane has a peripheral edge joined to the first housing body to create a reference pressure chamber. A second housing body made of ceramic material is opposite the membrane and is joined to the peripheral edge of the membrane, the second housing body together with the membrane forming a measurement pressure chamber. The second housing body has a port for connecting the pressure measuring cell to a medium to be measured. The first housing body, the second housing body and the membrane are tightly connected along the peripheral edge of the membrane in a central area of the first housing body a hole is formed, reaching through the first housing body and at least in the central region of the membrane and opposite the hole a surface of the membrane is formed as a first optically reflective area.

Abstract: A manufacturing method for a vacuum measuring cell provides first and second Al2O3 ceramic or sapphire housing bodies on opposite sides of an Al2O3 ceramic or sapphire membrane sealed to the bodies at its opposite peripheral edges. A reference vacuum chamber and a measuring vacuum chamber are on opposite sides of the membrane. An optical transparent window is provided in the first housing body and an optically reflective material is provided on a central region of the membrane. A lens is above the optical transparent window for optically linking to the optically reflective material on the membrane and an optical fiber outside the reference vacuum chamber and at a distance from the optical transparent window feeds light through the lens and window and in and out onto the optically reflective material on the membrane so that the level of membrane deflection is detected by a Fabry-Perot Interferometer.

Abstract: A vacuum measuring cell with a membrane between two planar housing parts has a first housing part forming a reference vacuum volume and the second housing part forming a measuring vacuum volume with a connection for the medium to be measured and a mechanism for measuring the membrane deflection. The membrane surface exposed to the medium to be measured is a structured surface.

Abstract: A shield arrangement for a vacuum measuring cell has a tubular shield housing encompassing a shield and an exit port for connection to a vacuum measuring cell and a connection opening for the object space to be measured. The shield is between the two openings and is implemented as a screw shield with spiral convolutions, its thread flange in the outer diameter being in contact on the inner wall of the shield housing such that a gas throughflow between the outer diameter of the thread flange and the inner wall is inhibited and is substantially forced into the spiral thread flight, and the exit port is on one side of the tubular section and the connection opening is on the other, opposite side and the screw shield is implemented such that in the axial line of vision the shield arrangement between the two openings is optically tight.

Abstract: A manufacturing method for a vacuum measuring cell provides first and second Al2O3 ceramic or sapphire housing bodies on opposite sides of an Al2O3 ceramic or sapphire membrane sealed to the bodies at its opposite peripheral edges. A reference vacuum chamber and a measuring vacuum chamber are on opposite sides of the membrane. An optical transparent window is provided in the first housing body and an optically reflective material is provided on a central region of the membrane. A lens is above the optical transparent window for optically linking to the optically reflective material on the membrane and an optical fibre outside the reference vacuum chamber and at a distance from the optical transparent window feeds light through the lens and window and in and out onto the optically reflective material on the membrane so that the level of membrane deflection is detected by a Fabry-Perot Interferometer.

Abstract: An electron-emitting cathode consists of an electrically conducting emitter layer attached to a side wall which consists of stainless steel and a gate which is fixed at a mall distance inside a concave emitter surface of the emitter layer. The cathode surrounds a reaction area containing a cylindrical grid-like anode and a central ion collector which consists of a straight axial filament. An ion collector current reflecting the density of the gas in the reaction region is measured by a current meter while a gate voltage is kept between the ground voltage of the emitter layer and a higher anode voltage and is regulated in such a way that an anode current is kept constant. The emitter layer may consists of carbon nanotubes, diamond-like carbon, a metal or a mixture of metals or a semiconductor material, e.g., silicon which may be coated, e.g., with carbide or molybdenum. The emitter surface can, however, also be a portion of the inside surface of the side wall roughened by, e.g., chemical etching.

Abstract: A vacuum measuring cell has a first housing body and a membrane, both of Al2O3 ceramic or sapphire. The membrane is planar with a peripheral edge joined by a first seal to the first housing body to form a reference vacuum chamber. A second housing body of Al2O3 ceramic or sapphire opposite the membrane, is joined to the peripheral edge of the membrane by a second seal to form a measurement vacuum chamber. A port connects the vacuum measuring cell to a medium to be measured. At least in the central area of the first housing body, an optical transparent window is formed and at least the central region of the membrane has an optically reflective surface. Outside the reference vacuum chamber, in opposition to and at a distance from the window, an optical fibre is arranged for feeding in and out light onto the surface of the membrane.

Abstract: A shield arrangement for a vacuum measuring cell has a tubular shield housing encompassing a shield and an exit port for connection to a vacuum measuring cell and a connection opening for the object space to be measured. The shield is between the two openings and is implemented as a screw shield with spiral convolutions, its thread flange in the outer diameter being in contact on the inner wall of the shield housing such that a gas throughflow between the outer diameter of the thread flange and the inner wall is inhibited and is substantially forced into the spiral thread flight, and the exit port is on one side of the tubular section and the connection opening is on the other, opposite side and the screw shield is implemented such that in the axial line of vision the shield arrangement between the two openings is optically tight.

Abstract: A capacitive vacuum measuring cell has a first housing body and a membrane, both of Al2O3 ceramic or sapphire. The membrane is planar with a peripheral edge joined by a first seal to the first housing body to form a reference vacuum chamber. A second housing body of Al2O3 ceramic or sapphire opposite the membrane, is joined to the peripheral edge of the membrane by a second seal to form a measurement vacuum chamber. A port connects the vacuum measuring cell to a medium to be measured. At least in the central area of the first housing body, an optical transparent window is formed and at least the central region of the membrane has an optically reflective surface. Outside the reference vacuum chamber, in opposition to and at a distance from the window, an optical fibre is arranged for feeding in and out light onto the surface of the membrane.

Abstract: An electron-emitting cathode consists of an electrically conducting emitter layer attached to a side wall which consists of stainless steel and a gate which is fixed at a mall distance inside a concave emitter surface of the emitter layer. The cathode surrounds a reaction area containing a cylindrical grid-like anode and a central ion collector which consists of a straight axial filament. An ion collector current reflecting the density of the gas in the reaction region is measured by a current meter while a gate voltage is kept between the ground voltage of the emitter layer and a higher anode voltage and is regulated in such a way that an anode current is kept constant. The emitter layer may consists of carbon nanotubes, diamond-like carbon, a metal or a mixture of metals or a semiconductor material, e.g., silicon which may be coated, e.g., with carbide or molybdenum. The emitter surface can, however, also be a portion of the inside surface of the side wall roughened by, e.g., chemical etching.