Abstract: Introduced herein are a dimensionless relationship between a volumetric flow rate, a head and a kinematic viscosity in a pump operation and a method that uses the dimensionless relationship to predict a viscous performance of a pump from water performance characteristics. Using the introduced dimensionless relationship, which is called Ketan's viscous head number, the introduced method determines a viscous head correlation that allows the prediction of the pump performance to be made accurately at any given speed, flow rate and viscosity. The introduced Ketan's viscous head number and method thus allow a prediction of a pump performance in a viscous application to be made from water performance characteristics without physically testing the pump in the viscous application.

Abstract: A plasma reaction cell includes a discharge chamber with a base plate, a side wall, and a cooling plate. A discharge stack mounted within the discharge chamber includes a first insulation plate, a first conductive spacer, a second insulation plate, and a second conductive spacer. An electrode electrically coupled to the first conductive spacer extends through the side wall of the discharge chamber. A first gas channel formed between the first conductive spacer and the first insulation plate has a first end in fluid communication with a first gas port and a second end in fluid communication with a second gas port. A second gas channel formed between the first conductive spacer and the second insulation plate has a first end in fluid communication with the first gas port and a second end in fluid communication with the second gas port.

Abstract: A system and method for controlling an amount of outgassing caused by implanting ions into a photoresist disposed on a workpiece. The amount of outgassing is based on the species being implanted, the type of photoresist, the energy of the implant, and the amount of dose that has already been implanted, among other effects. By controlling the effective beam current, the amount of outgassing may be maintained below a predetermined threshold. By developing and utilizing the relationship between effective beam current, dose completed and rate of outgassing, the effective beam current may be controlled more precisely to implant the workpiece in the most efficient manner while remaining below the predetermined outgassing threshold.

Abstract: This disclosure relates to a plasma processing system for controlling plasma density near the edge or perimeter of a substrate that is being processed. The plasma processing system may include a plasma chamber that can receive and process the substrate using plasma for etching the substrate, doping the substrate, or depositing a film on the substrate. This disclosure relates to a plasma processing system for controlling plasma density near the edge or perimeter of a substrate that is being processed. In one embodiment, the plasma density may be controlled by reducing the rate of loss of ions to the chamber wall during processing. This may include biasing a dual electrode ring assembly in the plasma chamber to alter the potential difference between the chamber wall region and the bulk plasma region.

Abstract: Apparatus and methods associated with operating a plasma torch are disclosed. According to some implementations, the apparatus and methods involve the delivery of a process gas to a shuttle valve at first and second pressures for the purpose of altering an axial position of a valve element located inside the shuttle valve. The shuttle valve is configured such that at different axial positions of the valve element the flow of process gas into the plasma torch is altered.

Abstract: A system for determining an operational state of an atmospheric pressure plasma. The system has a transformer for coupling power into the atmospheric pressure plasma, a current sampling circuit configured to sample at least one current pulse flowing through a primary winding of the transformer, and a programmed microprocessor configured to determine, from a waveform of the current pulse, the operational state of the atmospheric pressure plasma. The operational state is one of: a no plasma state, a plasma origination state indicative of an ignited arc expanding into a plasma by gas flow thereinto, and a plasma maintenance state indicative of the plasma being expanded.

Abstract: Provided herein are approaches for performing electrodynamic mass analysis with a radio frequency (RF) biased ion source to reduce ion beam energy spread. In some embodiments, a system may include an ion source including a power supply, the ion source operable to generate a plasma within a chamber housing, and an extraction power assembly including a first power supply and a second power supply electrically coupled with the chamber housing of the ion source, wherein the first power supply and the second power supply are operable to bias the chamber housing of the ion source with a time modulated voltage to extract an ion beam from the ion source. The system may further include an electrodynamic mass analysis (EDMA) assembly operable to receive the ion beam and perform mass analysis on the ion beam.

Abstract: Embodiments of systems, devices, and methods relating to a beam system. An example beam system includes a charged particle source configured to generate a beam of charged particles, a pre-accelerator system configured to accelerate the beam, and an accelerator configured to accelerate the beam from the pre-accelerator system. The pre-accelerator system can cause the beam to converge as it is propagated from the source to an input aperture of the accelerator. The pre-accelerator system can further reduce or eliminate source disturbance or damage caused by backflow traveling from the accelerator toward the source.

Abstract: A vacuum chuck includes a pedestal including a first surface on which a substrate may be mounted. The first surface of the substrate may include a vacuum hole to provide a vacuum pressure below the substrate, a vacuum groove connected to the vacuum hole, and a gas hole surrounding the vacuum groove to transmit a bottom gas to the substrate. A vacuum pipe may be provided to connect to the vacuum hole, and a gas pipe may be provided to connect to the gas hole. The diameter of the vacuum hole may be about 2 to about 3 micrometers, and a width of the vacuum groove may be about 1.6 to about 2.5 micrometers.

Abstract: A charged particle beam apparatus (100) is described. The charged particle beam apparatus includes a first vacuum region (121) in which a charged particle beam emitter (105) for emitting a charged particle beam (102) along an optical axis (A) is arranged, a second vacuum region (122) downstream of the first vacuum region and separated from the first vacuum region by a first gas separation wall (132) with a first differential pumping aperture (131), wherein the first differential pumping aperture (131) is configured as a first beam limiting aperture for the charged particle beam (102); and a third vacuum region (123) downstream of the second vacuum region and separated from the second vacuum region by a second gas separation wall (134) with a second differential pumping aperture (133), wherein the second differential pumping aperture (133) is configured as a second beam limiting aperture for the charged particle beam (102).

Abstract: An atomic beam generator includes a cathode constituted as a housing having an emission surface provided with an irradiation port through which an atomic beam is emissive; an anode disposed inside the cathode to generate plasma between the cathode and the anode; and a magnetic field generating unit including a first magnetic field generating unit that generates a first magnetic field and a second magnetic field generating unit that generates a second magnetic field, and guiding positive ions produced in the cathode to the emission surface by generating, in the cathode, the first magnetic field and the second magnetic field both parallel to the emission surface such that a magnetic field direction is leftward in the first magnetic field and is rightward in the second magnetic field when viewed from an emission surface side on condition of the first magnetic field being positioned above the second magnetic field.

Abstract: The present invention relates to a method of manufacturing a mold for a diffraction grating light guide plate by using two mask films, the mold having first to fourth pattern portions provided on one surface thereof, and to a method of manufacturing a diffraction grating light guide plate.

Abstract: The present invention prevents breakage of a chip by using a simple configuration even when an extraction-electrode power source cannot apply voltage to an extraction electrode due to a malfunction, etc. This charged particle beam device is provided with: a charged particle source; an extraction electrode that extracts charged particles from the charged particle source; an extraction-electrode power source that applies voltage to the extraction electrode; an accelerating electrode for accelerating the charged particles; an accelerating power source that applies voltage to the accelerating electrode; and a diode and a resistor which are connected in series between a middle stage of the accelerating power source and the output side of the extraction-electrode power source.

Abstract: An ion source includes a vacuum chamber having a cooling mechanism, an ion generation container for reacting an ionized gas with an ion material so as to generate ions, an extraction electrode for extracting ions generated in the ion generation container and generating an ion beam, and a shielding member provided inside and in the vicinity of an inner wall of the vacuum chamber, and having a main body made of a conductive metal for blocking deposition of an insulating material on the inner wall (10d) of the vacuum chamber. The main body of the shielding member has a plurality of protruding support portions that is in contact with the inner wall of the vacuum chamber for supporting the main body in a manner such that the main body is fitted at a distance from the inner wall of the vacuum chamber.

Abstract: A microwave processing system includes: a broadband variable frequency microwave (VFM) source; a plurality of waveguide applicators, each of which includes a waveguide transition and is capable of supporting a selected subset of frequencies within the bandwidth of the broadband VFM source; a microwave switching means allowing the microwave source to be connected to any one of the waveguide transitions so that microwave power is delivered to the corresponding waveguide applicator; and wherein each of the waveguide applicators includes at least one channel through which a microwave transparent tube may be run so that process fluid flowing through the tube may be exposed to microwave power in the applicator.

Abstract: A photon source comprising a quantum structure capable of defining one or more quantum levels such that a photon may be emitted from the quantum structure due to a transition between at least two quantum levels, a control signal configured to vary the transition energy, the transition energy being the energy separation between the at least two quantum levels; and a laser input beam configured to irradiate the quantum structure, the control signal being configured to bring the transition energy into resonance with the laser input beam and out of resonance with the laser input beam, such that the transition energy is resonant with the energy of the laser input beam for a time less than the time to output two photons from the transition.

Abstract: A cusped-field thruster for a space system, wherein the cusped-field thruster comprises: at least two substantially annular permanent magnets arranged in an antipolar manner, wherein a magnetic pole piece is formed between the permanent magnets, and an anode, which comprises a permanent-magnetic material. The cusped-field thruster is configured such that a cusp is formed in a region adjacent to the anode of the cusped-field thruster.

Abstract: In a configuration of an isolation circuit using a transformer of a high-frequency-isolation gate driver circuit in the frequency band from 1 to 100 MHz, a period for resetting the exciting current is eliminated, generation of self-resonance phenomenon after resetting is cancelled to reduce generation of noise current, and malfunctions of the switching element due to noise is prevented. In driving plural gate circuits by RF signals, exciting current is allowed to pass through a primary coil of a gate driver transformer alternately in both directions continuously all the time, in a configuration for isolating drive input signals by the gate driver transformer. Accordingly, the reset period that is required when the exciting current flows only in one way becomes unnecessary, and thus generation of self-resonance phenomenon after resetting is canceled. Then, generation of noise current caused by the self-resonance phenomenon is reduced.

Abstract: The present invention relates to methods and apparatus for ion milling, and more particularly relates to methods and apparatus for smoothing a surface using ion milling.

Abstract: An ion accelerator includes: an inner magnet having a channel extending through it in an axial direction; an outer magnet extending around the inner magnet, the magnets having like polarities so as to produce a magnetic field having two locations of zero magnetic field strength. The locations are spaced apart in the axial direction; and an anode and a cathode are arranged to generate an electrical potential difference between the locations.

Abstract: A plasma processing apparatus (5) comprises an outer shell (51) which is provided with a reaction chamber (52) in the interior, a bottom electrode which is arranged in the reaction chamber (52) and a cantilever support device (53) which goes through the outer shell (51) and supports the bottom electrode. The cantilever support device (53) is pivotally mounted on the side wall of the outer shell (51) and can rotate in the outer shell (51). The plasma processing apparatus (5) further comprises a locating device so as to selectively fix the relative position of the cantilever support device (53) and the outer shell (51).

Abstract: The invention relates to a method for operating an arc source, whereby an electric spark discharge is ignited and run on the surface of a target and the spark discharge is simultaneously fed a direct current with an associated constant voltage DV as well as a pulsed current generated by a periodically applied voltage signal. The voltage at the arc source is boosted over several microseconds and the shape of the voltage signal is in essence arbitrarily selectable.

Abstract: A method for managing the broad band microwave and TeraHertz (THz) radiation in a free electron laser (FEL) having a wiggler producing power in the electromagnetic spectrum. The method includes placement of broadband microwave and TeraHertz (THz) radiation absorbers on the upstream end of the wiggler. The absorbers dampen the bounced back, broad band microwave and THz radiation returning from the surfaces outside the nose of the cookie-cutter and thus preventing broadening of the electron beam pulse's narrow longitudinal energy distribution. Broadening diminishes the ultimate laser power from the wiggler. The broadband microwave and THz radiation absorbers are placed on either side of the slot in the cookie-cutter that shapes the wake field wave of the electron pulse to the slot shape of the wiggler chamber aperture. The broad band microwave and THz radiation absorber is preferably a non-porous pyrolytic grade of graphite with small grain size.

Abstract: A method for temporally and spatially aligning a laser-based x-ray source and maintaining alignment is disclosed. A pump laser beam, which interacts with a plasma source to create an electron beam, is aligned with the electron beam. A scattering laser beam is overlapped with the pump laser beam at an intersection point. The pump laser beam and scattering laser beam alignments are monitored and adjusted to maintain optimal alignment during operation of the laser-based x-ray source.

Abstract: A RF electrode for generating, plasma in a plasma chamber comprising an optical feedthrough. A plasma chamber comprising an RF electrode and a counter-electrode with a substrate support for holding a substrate, wherein a high-frequency alternating field for generating the plasma can be formed between the RF electrode and the counter-electrode. The chamber comprising an RF electrode with an optical feedthrough. A method, for in situ analysis or in situ processing of a layer or plasma in a plasma chamber, wherein the layer is disposed on counter-electrode and an RF electrode is disposed on the side lacing the layer. Selection of an RF electrode having an optical feedthrough, and at least one step in which electromagnetic radiation is supplied through the optical feedthrough for purposes of analysis or processing of the layer or the plasma, and by at least one other step in which the scattered or emitted or reflected radiation is supplied to an analysis unit.

Abstract: A multiple function atmospheric pressure ion source interfaced to a mass spectrometer comprises multiple liquid inlet probes configured such that the sprays from two or more probes intersect in a mixing region. Gas phase sample ions or neutral species generated in the spray of one probe can react with reagent gas ions generated from one or more other probes by such ionization methods as Electrospray, photoionization, corona discharge and glow discharge ionization. Reagent ions may be optimally selected to promote such processes as Atmospheric Pressure Chemical Ionization of neutral sample molecules, or charge reduction or electron transfer dissociation of multiply charged sample ions. Selected neutral reagent species can also be introduced into the mixing region to promote charge reduction of multiply charged sample ions through ion-neutral reactions. Different operating modes can be performed alternately or simultaneously, and can be rapidly turned on and off under manual or software control.

Abstract: A system for adaptive electron beam scanning may include an inspection sub-system configured to scan an electron beam across the surface of a sample. The inspection sub-system may include an electron beam source, a sample stage, a set of electron-optic elements, a detector assembly and a controller communicatively coupled to one or more portions of the inspection sub-system. The controller may assess one or more characteristics of one or more portions of an area of the sample for inspection and, responsive to the assessed one or more characteristics, adjust one or more scan parameters of the inspection sub-system.

Abstract: A high brightness ion source with a gas chamber includes multiple channels, wherein the multiple channels each have a different gas. An electron beam is passed through one of the channels to provide ions of a certain species for processing a sample. The ion species can be rapidly changed by directing the electrons into another channel with a different gas species and processing a sample with ions of a second species. Deflection plates are used to align the electron beam into the gas chamber, thereby allowing the gas species in the focused ion beam to be switched quickly.

Abstract: Methods and apparatus for a carbon ion source head. An ionization chamber is configured to receive a process gas containing carbon and a noble carrier gas; a cathode is disposed in the ionization chamber and configured to emit electrons in thermionic emission; a graphite coating is provided on at least a portion of the cathode; and an outlet on the ionization chamber is configured to output carbon ions. A method for ion implantation of carbon is disclosed. Additional alternative embodiments are disclosed.

Abstract: An ion source for use in a radiation generator includes an active cathode configured to emit electrons on a trajectory away from the active cathode, at least some of the electrons as they travel interacting with an ionizable gas to produce ions. In addition, there is at least one extractor downstream of the active cathode having a potential such that the ions are attracted toward the at least one extractor.

Abstract: An ion generator includes: an arc chamber; a repeller that includes a repeller plate provided within the arc chamber and a repeller extension portion inserted through a through hole communicating the inside and the outside of the arc chamber; and a supporting structure that is provided outside the arc chamber and that supports the repeller so that a gap is ensured between the repeller extension portion and an inner wall of the through hole. The supporting structure includes a cover member that forms, outside the arc chamber, a small chamber communicating with the gap, and an insulation member that electrically insulates the arc chamber and the repeller from each other.

Abstract: An insulation structure of high voltage electrodes includes an insulator having an exposed surface and a conductor portion, which includes a joint region in contact with the insulator, and a heat-resistant portion provided, along at least part of an edge of the joint region, in such a manner as to be adjacent to the exposed surface of the insulator. The heat-resistant portion is formed of an electrically conductive material whose melting point is higher than that of the conductor portion. The heat-resistant portion may be so provided as to have a gap between the insulator and the exposed surface.

Abstract: A sputter source is provided. The sputter source includes a shaft extending through a central region of the sputter source. A first end of the shaft is coupled to a drive and a second end of the shaft is coupled to a bottom plate. A first plate having a ramped surface is included where the first plate is stationary. A second plate having a ramped surface is provided where the second plate is disposed above the first plate such that portions of the ramped surfaces contact each other. The second plate is coupled to the shaft, wherein the second plate is operable to rotate and move axially as the shaft rotates in a first direction and wherein the second plate is operable to remain stationary as the shaft rotates in a second direction.

Abstract: A hybrid plasma reactor includes a reactor body having a plasma discharge space, a gas inlet, and a gas outlet; a hybrid plasma source including an inductive antenna inductively coupled to plasma formed in the plasma discharge space and a primary winding coil transformer coupled to the plasma and wound in a magnetic core; and an alternating switching power supply for supplying plasma generation power to the inductive antenna and the primary winding coil. The hybrid plasma reactor induces a plasma discharge using the inductively coupled plasma source and the transformer coupled plasma source, so that it has a wide operational area from a low pressure area to a high pressure area.

Abstract: An electron microscope is provided. In another aspect, an electron microscope employs a radio frequency which acts upon electrons used to assist in imaging a specimen. Furthermore, another aspect provides an electron beam microscope with a time resolution of less than 1 picosecond with more than 105 electrons in a single shot or image group. Yet another aspect employs a super-cooled component in an electron microscope.

Abstract: A system and method comprising an ion production chamber having a plasma source disposed in said chamber, a harvest gas disposed to flow through the chamber from an inlet to an outlet, and a jet, said jet operable to introduce a sample into the harvest gas flow. In some embodiments the system includes using helium as the harvest gas. Certain embodiments include introducing a sample perpendicular to the harvest gas flow and using multiple sample introduction jets to increase mixing efficiency. The charge sample may be coupled to a MEMS-based electrometer.

Abstract: A compact cold plasma device for generating cold plasma having temperatures in the range 65 to 120 degrees Fahrenheit. The compact cold plasma device has a magnet-free configuration and an induction-grid-free configuration. An additional configuration uses an induction grid in place of the input electrode to generate the cold plasma. A high voltage power supply is provided that includes a controllable switch to release energy from a capacitor bank to a dual resonance RF transformer. A controller adjusts the energy input to the capacitor bank, as well as the trigger to the controllable switch.

Abstract: A method is disclosed for reducing particle contamination in an ion implantation system, wherein an ion beam is created via the ion source operating in conjunction with an extraction electrode assembly. A cathode voltage is applied to the ion source for generating ions therein, and a suppression voltage is applied to the extraction assembly for preventing electrons in the ion beam from being drawn into the ion source. The suppression voltage is selectively modulated, thereby inducing a current flow or an arc discharge through the extraction assembly to remove deposits on surfaces thereof to mitigate subsequent contamination of workpieces.

Abstract: Described herein is a method and apparatus for removing metal oxides on a surface of a component via electron attachment. In one embodiment, there is provided a field emission apparatus, wherein the electrons attach to at least a portion of the reducing gas to form a negatively charged atomic ions which removes metal oxides comprising: a cathode comprising an electrically conductive and comprising at least one or more protrusions having a high surface curvature, wherein the cathode is surrounded by a dielectric material which is then surrounded by an electrically conductive anode wherein the cathode and anode are each connected to an electrical voltage source, and the dielectric material between the cathode and anode is polarized to provide an electric field at one or more protrusions and thereby electrons from the cathode.

Abstract: A device for generating a cold, HF-excited plasma under atmospheric pressure conditions can be used advantageously for plasma treatment of materials for cosmetic and medical purposes. The device contains a metal housing functioning as a grounded electrode in the region of the emergent plasma, wherein an HF generator, an HF resonance coil having a closed ferrite core suitable for the high frequency, an insulating body acting as a gas nozzle, and a high-voltage electrode mounted in the insulating body are disposed in such a manner that they are permeated or circulated around by process gas. By integrating the plasma nozzle and required control electronics in a miniaturized handheld device, or by using a short high-voltage cable, the invention allows compliance with the electromagnetic compatibility directives and allows the power loss to be minimized and thus a mobile application to be implemented.

Abstract: A switchable ion gun switchable between a cluster mode setting for producing an ion beam substantially comprising ionised gas clusters and an atomic mode setting for producing an ion beam substantially comprising ionised gas atoms, comprising: a source chamber having a first gas inlet; a gas expansion nozzle for producing gas clusters in the presence of gas atoms by expansion of a gas from the source chamber through the nozzle; an ionisation chamber for ionising the gas clusters and gas atoms; wherein the ionisation chamber has a second gas inlet for admitting gas directly into the ionisation chamber to form ionised gas atoms; and a variable mass selector for mass selecting the ionised gas clusters and ionised gas atoms to produce an ion beam variable between substantially comprising ionised gas clusters and substantially comprising ionised gas atoms.

Abstract: An ion source is provided that includes at least one electron gun. The electron gun includes an electron source for generating a beam of electrons and an inlet for receiving a gas. The electron gun also includes a plasma region defined by at least an anode and a ground element, where the plasma region can form a plasma from the gas received via the inlet. The plasma can be sustained by at least a portion of the beam of electrons. The electron gun further includes an outlet for delivering at least one of (i) ions generated by the plasma or (ii) at least a portion of the beam of electrons generated by the electron source.

Abstract: In accordance with one embodiment of the present invention, an end-Hall ion source has an electron emitting cathode, an anode, a reflector, an internal pole piece, an external pole piece, a magnetically permeable path, and a magnetic-field generating means located in the permeable path between the two pole pieces. The anode and reflector are enclosed without contact by a thermally conductive cup that has internal passages through which a cooling fluid can flow. The closed end of the cup is located between the reflector and the internal pole piece and the opposite end of the cup is in direct contact with the external pole piece, and wherein the cup is made of a material having a low microhardness, such as copper or aluminum.

Abstract: The present disclosure provides for various advantageous methods and apparatus of controlling electron emission. One of the broader forms of the present disclosure involves an electron emission element, comprising an electron emitter including an electron emission region disposed between a gate electrode and a cathode electrode. An anode is disposed above the electron emission region, and a voltage set is disposed above the anode. A first voltage applied between the gate electrode and the cathode electrode controls a quantity of electrons generated from the electron emission region. A second voltage applied to the anode extracts generated electrons. A third voltage applied to the voltage set controls a direction of electrons extracted through the anode.

Abstract: A showerhead electrode assembly for a plasma processing chamber, which includes a showerhead electrode; a heater plate secured to the showerhead electrode; at least one pressure controlled heat pipe secured to an upper surface of the heater plate, the at least one pressure controlled heat pipe having a heat transfer liquid contained therein, and a pressurized gas, which produces a variable internal pressure within the at least one pressure controlled heat pipe; a top plate secured to an upper surface of the at least one heat pipe; and wherein the variable internal pressure within the at least one pressure controlled heat pipe during heating of the showerhead electrode by the heater plate displaces the heat transfer liquid from a thermal path between the top plate and the heater plate, and when removing excess heat from the showerhead electrode returns the heat transfer liquid to the thermal path.

Abstract: The invention relates to a system for generating an ion stream which may be useful for various applications. In one application, the ion stream may be used to excite nano-spheres. In another application, the ion stream may be used for sterilization and therapy in accordance with the teachings of the invention.

Abstract: A temperature controlled dielectric window of an inductively coupled plasma processing chamber includes a dielectric window forming a top wall of the plasma processing chamber having at least first and second channels therein. A liquid circulating system includes a source of cold liquid circulating in a first closed loop which is not in fluid communication with the channels, a source of hot liquid circulating in a second closed loop which is in fluid communication with the channels, and first and second heat exchangers. The cold liquid passes through the first heat exchanger at a controllable flow rate and temperature of the hot liquid is adjusted by heat exchange with the cold liquid as the hot liquid passes through the first heat exchanger and then through the inlet of the first channel.

Abstract: A field emission device is configured as a heat engine, wherein the configuration of the heat engine is variable as a function of time. A method corresponding to a field emission device comprises applying an anode electric potential to an anode region that is greater than a cathode electric potential of a cathode region, applying a gate electric potential to a gate region to release a set of electrons from the cathode region, passing the set of electrons from the gate region to a suppressor region, applying a suppressor electric potential to decelerate the set of electrons between the suppressor region and the anode region, binding the set of electrons in the anode region, and varying at least one of the anode electric potential, gate electric potential, and suppressor electric potential as a function of time.

Abstract: An ion source uses at least one induction coil to generate ac magnetic field to couple rf/VHF power into a plasma within a vessel, where the excitation coil may be a single set of turns each turn having lobes or multiple separate sets of windings. The excitation coil is positioned outside and proximate that side of the vessel that is opposite to the extraction slit, and elongated parallel to the length dimension of the extraction slit. The conducting shield(s) positioned outside or integrated with the well of the vessel are used to block the capacitive coupling to the plasma and/or to collect any rf/VHF current may be coupled into the plasma. The conducting shield positioned between the vessel and the coil set can either shield the plasma from capacitive coupling from the excitation coils, or be tuned to have a higher rf/VHF voltage to ignite or clean the source.

Abstract: The present invention relates to inductively coupled plasma mass spectrometry (ICPMS) in which a collision cell is employed to selectively remove unwanted artefact ions from an ion beam by causing them to interact with a reagent gas. The present invention provides a first evacuated chamber (6) at high vacuum located between an expansion chamber (3) and a second evacuated chamber (20) containing the collision cell (24). The first evacuated chamber (6) includes a first ion optical device (17). The collision cell (24) contains a second ion optical device (25). The provision of the first evacuated chamber (5) reduces the gas load on the collision cell (24), by minimising the residual pressure within the collision cell (24) that is attributable to the gas load from the plasma source (1). This serves to minimise the formation, or re-formation, of unwanted artefact ions in the collision cell (24).