Abstract: A turbo-molecular vacuum pump of increased pumping capacity has parallel access toward two initial impeller-rotors. An additional annular space is provided around the periphery of the first rotor and the conventional first stator disc is omitted, thus creating an accelerated annual gas flow entering directly into the second rotor without an accumulation of pressure.

Abstract: A vacuum pump includes a housing having an inlet port and an exhaust port, at least one molecular drag stage within the housing, the molecular drag stage including a rotor and a stator that defines a tangential flow channel which opens onto a surface of the rotor, and a motor that rotates the rotor so that gas is pumped from the inlet port to the exhaust port. The stator defines one or more obstructions in the channel. The obstructions alter gas flow through the channel and produce turbulence under viscous or partially viscous flow conditions.

Abstract: A hybrid turbomolecular vacuum pump includes a housing having an inlet port and an exhaust port, one or more axial flow stages located within the housing, each of the axial flow stages including a stator and an impeller, each having inclined blades, at least one additional vacuum pumping stage which is not an axial flow stage, the additional vacuum pumping stage being located within the housing and including a stator and an impeller, and a motor to rotate the impellers such that gas is pumped from the inlet port to the exhaust port. The vacuum pump does not include a molecular drag stage having a rotating cylindrical drum or a rotating disk with a flat pumping surface. The additional vacuum pumping stage may be a modified molecular drag stage, wherein the impeller includes a disk having a roughened or grooved pumping surface, and/or a regenerative stage.

Abstract: Vacuum pumping apparatus includes a housing, one or more primary pumping stages disposed in the housing, a motor coupled to the primary pumping stages, the motor including at least one stationary surface and at least one moving surface when the motor is energized, the stationary and moving surfaces of the motor defining an auxiliary pumping stage coupled in series with the primary pumping stages to pump gas through a pumping channel between the stationary and moving surfaces of the motor, the housing having a first exhaust port between the primary pumping stages and the auxiliary pumping stage, and a second exhaust port at an outlet of the auxiliary pumping stage, and a valve connected in series with the first exhaust port and configured to close when an inlet pressure of the vacuum pumping apparatus is below a predetermined pressure.

Abstract: A vacuum pump includes a housing having an inlet port and an exhaust port, at least one molecular drag stage within the housing, the molecular drag stage including a rotor and a stator that defines a tangential flow channel which opens onto a surface of the rotor, and a motor that rotates the rotor so that gas is pumped from the inlet port to the exhaust port. The stator defines one or more obstructions in the channel. The obstructions alter gas flow through the channel and produce turbulence under viscous or partially viscous flow conditions.

Abstract: A vacuum pump includes a housing having an inlet port and an exhaust port, at least one molecular drag stage within the housing, the molecular drag stage including a rotor in the form of a molecular drag disk and a stator that defines a tangential flow channel which opens onto a surface of the disk, the rotor having an axis of rotation, and a motor that rotates the rotor so that gas is pumped from the inlet port to the exhaust port. The channel has a cross-section in a plane that contains the axis of rotation which varies in dimension as a function of distance from the axis of rotation. The channel cross-section is selected to limit the tendency for backflow in viscous or partially viscous flow conditions.

Abstract: A molecular drag compressor includes a rotor disk coupled to a drive shaft for rotation about an axis, a stator disposed about the rotor disk, the stator defining a tangential flow channel, an inlet to the tangential flow channel and an outlet from the tangential flow channel, and a stationary baffle disposed in the tangential flow channel adjacent to the outlet. The baffle and the rotor disk have a gap between them. A surface of the baffle facing the rotor disk has cavities configured to produce turbulent gas flow through the gap between the baffle and the rotor disk and to thereby reduce leakage.

Abstract: A hybrid turbomolecular vacuum pump includes a housing having an inlet port and an exhaust port, one or more axial flow stages located within the housing, each of the axial flow stages including a stator and an impeller, each having inclined blades, at least one additional vacuum pumping stage which is not an axial flow stage, the additional vacuum pumping stage being located within the housing and including a stator and an impeller, and a motor to rotate the impellers such that gas is pumped from the inlet port to the exhaust port. The vacuum pump does not include a molecular drag stage having a rotating cylindrical drum or a rotating disk with a flat pumping surface. The additional vacuum pumping stage may be a modified molecular drag stage, wherein the impeller includes a disk having a roughened or grooved pumping surface, and/or a regenerative stage.

Abstract: A molecular drag compressor includes a rotor disk coupled to a drive shaft for rotation about an axis, a stator disposed about the rotor disk, the stator defining a tangential flow channel, an inlet to the tangential flow channel and an outlet from the tangential flow channel, and a stationary baffle disposed in the tangential flow channel adjacent to the outlet. The baffle and the rotor disk have a gap between them. A surface of the baffle facing the rotor disk has cavities configured to produce turbulent gas flow through the gap between the baffle and the rotor disk and to thereby reduce leakage.

Abstract: A vapor jet vacuum pump includes a housing having an inlet port and a foreline conduit, a vapor jet assembly within the housing, a vapor source for supplying a vapor to the vapor jet assembly, and at least one ejector stage. The ejector stage includes an ejector nozzle mounted in the foreline conduit and a fluid inlet located external to the housing and coupled by an ejector conduit to the ejector nozzle. The fluid inlet may be an air inlet for drawing in air at atmospheric pressure. The ejector stage may be driven by a backing pump coupled to the foreline conduit.

Abstract: A vapor jet vacuum pump includes a housing having an inlet port and a foreline conduit, a vapor jet assembly within the housing, a vapor source for supplying a vapor to the vapor jet assembly, and at least one ejector stage. The ejector stage includes an ejector nozzle mounted in the foreline conduit and a fluid inlet located external to the housing and coupled by an ejector conduit to the ejector nozzle. The fluid inlet may be an air inlet for drawing in air at atmospheric pressure. The ejector stage may be driven by a backing pump coupled to the foreline conduit.

Abstract: Methods and apparatus for controlling power supplied to vapor jet vacuum pumps are provided. A vapor jet vacuum pumping system includes a vapor jet pump having an inlet port, an exhaust port, a jet assembly and an boiler, the boiler including a heater, and a power controller for automatically controlling power supplied to the heater in response to at least one control parameter. The power may be controlled in response to a programmed sequence, to a sensed pressure in a process chamber, to control signals from a process control system, or to combinations of these control parameters.

Abstract: A vacuum pump includes a housing having an inlet port and an exhaust port, a plurality of vacuum pumping stages located within the housing and disposed between the inlet port and the exhaust port, and a motor. The vacuum pumping stages include gas drag stages, each including a stator and an impeller. The impellers of successive ones of the gas drag stages are configured for efficient operation at progressively higher pressures. The impellers of the gas drag stages may have pumping surfaces with a surface topography for efficient operation at progressively higher pressures. The motor rotates the impellers such that gas is pumped from the inlet port to the exhaust port.

Abstract: Vacuum pumping apparatus includes a rotor, a motor for rotating the rotor about an axis of rotation, a stator mounted in proximity to the rotor and a housing enclosing the rotor and the stator. The stator includes at least one spiral channel having an open side facing the rotor. The housing defines an inlet in fluid communication with the inner portion of the spiral channel. Gas is pumped outwardly with respect to the axis of rotation through the spiral channel as the motor rotates the rotor. The stator may include two or more spiral channels coupled in parallel. The spiral channels may decrease in cross-sectional area from larger at the inner portion of the stator to smaller at the outer portion of the stator. The vacuum pumping apparatus may include a second vacuum pumping stage on a second side of the rotor and a series connection between the first and second vacuum pumping stages. The second vacuum pumping stage may have a variety of different configurations.

Abstract: A vacuum pump, such as a turbomolecular pump, a molecular drag pump or a hybrid pump, is adapted for use with a backing pump. The vacuum pump includes a housing having an inlet port and an exhaust port for coupling to the backing pump, one or more vacuum pumping stages disposed in the housing, each of the vacuum pumping stages having a stationary member and a rotating member, and a gas turbine. The gas turbine includes a gas inlet, a gas outlet coupled to the exhaust port, and a rotor coupled to the rotating members of the vacuum pumping stages. A gas flow, produced by the backing pump, through the gas turbine causes the rotor and the rotating members of the vacuum pumping stages to rotate, wherein gas is pumped by the vacuum pumping stages from the inlet port to the exhaust port.

Abstract: A high-vacuum pump includes a first vacuum pump section and a second vacuum pump section coupled in series and having an interstage region between them. The vacuum pump further includes a housing containing the first and second vacuum pump sections. The housing includes a high conductance peripheral duct surrounding all or part of the interstage region and coupled to the interstage region. The housing defines a first inlet port coupled to an inlet of the first vacuum pump section, a second inlet port coupled to the peripheral duct, and an exhaust port coupled to an outlet of the second vacuum pump section. Examples of high-vacuum pumps according to the invention include turbomolecular vacuum pumps, diffusion pumps and mixed vacuum pumps which include both axial flow stages and molecular drag stages.

Abstract: A vacuum pump includes a housing having an inlet port and an exhaust port, a motor disposed in the housing, and one or more vacuum pumping stages disposed in the housing and operationally coupled to the motor for pumping gas from the inlet port to the exhaust port. The motor includes a stator disposed on a central axis and a rotor disposed around the stator. The rotor rotates about the central axis when the motor is energized. The motor may be located at the center of the housing, and the vacuum pumping stages may be disposed around the motor in an annular configuration. The inverted motor configuration facilitates a compact vacuum pump structure.

Abstract: Vacuum pumping apparatus includes a non-scroll type auxiliary pump and a scroll pump disposed in a single housing. The auxiliary pump and the scroll pump are connected in series and are driven by a common motor. Typically, the auxiliary pump has a relatively high pumping speed and the scroll pump has a relatively high compression ratio. The auxiliary pump may be a regenerative blower, a roots-type blower or a screw-type blower. When a co-rotating scroll pump is utilized, a regenerative blower may be formed at or near the outer periphery of a disk on which the non-orbiting scroll blade is mounted. In another configuration, first and second scroll pumps are disposed within a housing. The scroll blade sets of the first and second scroll pumps have different orbiting radii. Scroll pump leakage may be reduced by forming a closed-loop seal around the inlet region of the scroll pump and connecting the inlet region to an intermediate pressure.

Abstract: A molecular drag compressor includes a rotor disk and a stator that defines a tangential flow channel having an inlet and an outlet. A stationary baffle is disposed in the tangential flow channel adjacent to the outlet. The baffle is spaced from the rotor disk by a gap. A surface of the baffle facing the rotor disk has surface irregularities including peaks for defining the gap and valleys between the peaks for accumulation of particles. The surface irregularities may form a series of grooves. The molecular drag compressor is preferably utilized in a high vacuum pump which includes an axial turbomolecular compressor and a molecular drag compressor. Additional features which limit the effect of particulate accumulation in molecular drag compressors are disclosed.

Abstract: A single potential ion source includes a single conical electrode encircled by a cylindrical magnet. At least one filament is placed proximate to the electrode. This arrangement serves to accelerate electrons created by energy from the filament toward a center axis of the conical electrode. The electrons collide with gas particles to create a focused ion stream. The stream may be directed into a magnetic field in a mass spectrometer tube.