Abstract: An electronic circuit and a method of generating an electrical discharge for an ionization detector system. The electronic circuit includes a transformer with a primary portion and a secondary portion. The circuit and method produce an electrical discharge across a set of electrodes. The discharge is stable over time and has relatively low peak currents associated therewith.

Abstract: A wireless sensor assembly for circumferential monitoring of gas stream properties comprises a drive system attachable to a hot gas path housing. A rake is movably coupled to the drive system for unrestricted circumferential movement. At least one RF sensor is disposed on the rake for generating a signal responsive to the gas stream properties. Circuitry is provided for remotely powering the at least one RF sensor and for remotely detecting the signal.

Abstract: Materials display innate resistance, capacitance, and inductance (RCL) properties and can therefore be distinguished in accordance with these properties. A high voltage is applied across a material, and a waveform is obtained whose rise time, frequency content, duration, and fall time represent the RCL properties of the material. The high voltage can be applied by passing air containing the material through a pair of screens held at a potential difference or by gluing a sample of the material to two rods held at a potential difference. The voltage may or may not be enough to cause the material to arc.

Abstract: It is sought to provide an ion measuring device, which can accurately and readily measure both positive and negative ion data and realize its size and thickness reduction.

Abstract: An ionizer that creates a corona current distribution having a balanced flow of positive and negative ions in a variable ion mobility gaseous environment, such as an environment of substantially nitrogen. The balanced flow of positive and negative ions is directed toward a workspace or target located in the gaseous environment downstream from the ionizer. The ionizer includes a counterelectrode, a positive ion emitter, a negative ion emitter, and a control circuit. The counterelectrode has at least two spatially isolated collecting surfaces. The positive and negative ion emitters are spatially isolated from each other so that the outputs of each of the emitters do not reach the other emitter.

Abstract: It is sought to provide an air ion measuring device, which permits holding the air passage rate in an ion detector as constant as possible to provide for improved air ion measurement reliability, permits its size and thickness reduction and also reduction of parts cost of the ion detector, permits ready cleaning thereof, provides a measure for coping with static electricity, provides good visual recognition property in the air ion data display and has excellent display property of displaying such data as other necessary data than air ion data and error data. An ion detector structure is formed by disposing a charge collector electrode 4 and repelling electrodes 5 in the vicinity of the opposite ends of the charge collector electrode on one side surface of an air passage 3, through which air is withdrawn from one end portion and exhausted from the other end portion, and disposing a further repelling electrode 6 on the other side surface of the air passage.

Abstract: A gas concentration detector for detecting a concentration of pollutant gas such as NOx or SOx contained in ambient air is composed of an oxide-semiconductor gas sensor heated by a heater and a controller for determining the gas concentration by comparing a concentration level detected by the gas sensor with a calculated comparison level. The comparison level is calculated so that it follows the detected level with a certain delay. The degree of the delay is set shorter in an unstable region- of the gas sensor than in a stable region, thereby to effectively determine the gas concentration even in the unstable region.

Abstract: A process of manufacturing a semiconductor device utilizing a thermo-chemical reaction is started based on preset initial settings, a state function of an atmosphere associated with the thermo-chemical reaction is measured, a state of the atmosphere and a change thereof are analyzed based on measurement data obtained by the measurement, and then, analysis data obtained by the analysis is fed back to a manufacturing process.

Abstract: A liquid metal ion source has an emitter electrode for emitting ions, an extraction electrode, proximate the emitter electrode for generating a focused electric field at a tip of the emitter electrode, and a suppression electrode proximate the extraction electrode for adjusting the strength of the focused electric field generated at the tip of the emitter electrode so that metal ions are extracted from liquid metal covering the tip of the emitter electrode at a desired emission current value. A storage device stores a function defining a relationship between variation (&Dgr;Ie) in current of the emitter electrode and variation (&Dgr;Vsup) in voltage of the suppression electrode as a function &Dgr;Ie=F(&Dgr;Vsup), with the voltage (Vext) of the extraction electrode being at a fixed value.

Abstract: A radio frequency (RF) probe analysis system has a broadband design. The analysis system includes a sampling unit for generating digital power signals based on a plurality of analog signals. The analog signals characterize power delivered from an RF power delivery system to a plasma chamber. The analysis system further includes a digital processing unit for generating a digital spectrum signal based on the digital power signals. The sampling unit simultaneously samples a first plurality of frequencies from the analog signals such the that digital spectrum signal defines signal levels for the first plurality of frequencies. The sampling unit may also simultaneously sample a second plurality of frequencies from the analog signals such that the digital spectrum signal further defines signal levels for the second plurality of frequencies. The broadband architecture of the sampling unit enables closed loop control of power delivered to the chamber to tolerances unachievable through conventional approaches.

Abstract: A detection device for analyzing charged particles. The charged particle analyzer comprises a source of charged particles and a charged particle detector spaced from the source and immersed within the source in an ionizable gas. The detector comprises at least one pair of electrodes, characterized in that the electrodes of the pair are spaced apart by a distance that is substantialy less than the spacing between the source and detector. The electrodes of the pair are maintained at different potentials, and the source is maintained at a potential different from the potentials of the electrodes. The potentials are selected such that charged particles emitted by the source are attracted from the source toward each of the pair of electrodes and such that charged particles adjacent the detector are accelerated to energies sufficient to ionize the gas.

Abstract: An apparatus for and method of making a discharge ionization detector. The apparatus comprises a detector body, a detector cavity, located in the detector body and having a discharge electrode and an second discharge electrode, wherein an electric discharge runs between the second discharge electrode and the discharge electrode, and a signal electrode which attracts ionized molecules, an inlet interface, through which a discharge gas enters the detector, an analyte inlet, through which the analyte enters the detector cavity, and an outlet through which the analyte and discharge gas exit the detector body, wherein the apparatus is hermetically sealed. The apparatus is hermetically sealed by vacuum brazing the components to the detector body. The present invention can also have a detector volume as small as 10 micro-liters or less.

Abstract: A method of fault identification in a plasma process powered by an RF source comprises initially determining, in respect of a given baseline plasma process, the changes in magnitude of a plurality of Fourier components of the RF source resulting from changes in a plurality of the process input parameters from their baseline values. These magnitude changes are stored as reference data. During a subsequent production run, the plasma process is monitored for faults and if one is found the baseline process is repeated with input parameter values nominally the same as the original baseline values. The changes in the Fourier components from the original baseline values are determined and compared with the reference data to determine which input parameter(s) have changed.

Abstract: In a plasma processing system, displacement current is removed from a current measurement by providing a secondary capacitor connected in parallel with a primary capacitor defined by an anode and a cathode spaced from one another within the plasma doping chamber. The secondary capacitor is chosen or adjusted to have a same or nearly the same capacitance as the primary capacitor. When a voltage pulse is applied to both the primary and secondary capacitors, the respective currents through the capacitors are measured. In order to remove the effects of the displacement current that is present at the leading and falling edges of the voltage pulse, and in order to measure the ion current within the doping chamber, the secondary current through the secondary capacitor is subtracted from the primary current through the primary capacitor.

Abstract: A sensor for detecting the flame occurring during a flashback condition in the fuel nozzle of a lean premix combustion system is presented. The sensor comprises an electrically isolated flashback detection electrode and a guard electrode, both of which generate electrical fields extending to the walls of the combustion chamber and to the walls of the fuel nozzle. The sensor is positioned on the fuel nozzle center body at a location proximate the entrance to the combustion chamber of the gas turbine combustion system. The sensor provides 360° detection of a flashback inside the fuel nozzle, by detecting the current conducted by the flame within a time frame that will prevent damage to the gas turbine combustion system caused by the flashback condition.

Abstract: An oxygen sensor device consisting a cylindrical tube of a ceramic solid electrolyte having an oxygen ion conducting property, a reference electrode formed on an inner surface of the cylindrical tube, and a measuring electrode formed on an outer surface of the cylindrical tube at a position at least opposed to the reference electrode, wherein a ceramic layer is formed on the outer surface of the cylindrical tube, the ceramic layer having an opening portion for exposing the surface of the measuring electrode and incorporating a heat-generating member therein, the heat-generating member being buried surrounding the opening portion. The oxygen sensor device as a whole has a cylindrical shape relaxing the concentration of thermal stress and exhibiting excellent thermal shock resistance. With the heat-generating member being buried near the sensing portion, the sensing portion is heated up to a predetermined activating temperature within short periods of time exhibiting an excellent sensor response.

Abstract: A measuring device for determining the oxygen content in gases is described. The measuring device is disposed between two magnets that are positioned at a distance from one another. The measuring device is equipped with a sensor that is held rotatably within a frame. The sensor has two parallelepipedic bodies that are both made hollow or solid and are connected to one another via a web-shaped structural element. The web-shaped structural element is fastened to the frame via at least one holding element, so that the sensor can be rotated about its center of gravity. The amount of rotation is dependent on the quantity of oxygen that is concentrated between the two magnets. A current can be conducted through a conductor track led on the surface of the sensor and generates a correspondingly high restoring force by which the sensor is brought into the position of rest again.

Abstract: The present invention is a method by which the deterioration judgement and the correction of an electrochemical carbon monoxide gas sensor are simply carried out without using the correction gas. The method of the present invention is that: the voltage is applied from the outside so that the working electrode of the electrochemical carbon monoxide gas sensor is operated as the negative electrode, and the counter electrode is operated as the positive electrode, and hydrogen is generated from the working electrode, and oxygen is generated from the counter electrode; after that, the potential of the working electrode and the counter electrode is returned to the operation potential as the sensor; and by using the reaction on the hydrogen remained in the vicinity of the working electrode, the sensor current is generated, thereby, it is tested whether the sensor is normally operated.

Abstract: The subject of the invention is a method for minimizing Coulombic losses in impactors and an impactor, in which Coulombic losses have been minimized. The method according to the invention is based on restricting the force effect of the charges accumulated in impactor's insulators on the charged particles. This restriction of the force effect can be realized, for example, by placing an electrically conductive surface between the insulator and the flow, or by forming an insulator so that the force effect is minimized.

Abstract: An ionizer creates a corona current distribution having a balanced flow of positive and negative ions in a variable ion mobility gaseous environment. The balanced flow of positive and negative ions are directed toward a workspace or target located in the gaseous environment and downstream from the ionizer. The ionizer includes a corona electrode, a counterelectrode, a corona-free dc bias electrode, and a control circuit. The corona electrode has a negative polarity. The counterelectrode has an ion collecting surface. The corona-free dc bias electrode has a positive polarity. The control circuit controls the output of the corona-free electrode so as to cause a balanced flow of positive and negative ions to be emitted from the ionizer and directed towards the workspace or target. In this manner, a static-free environment is created at the workspace or target.

Abstract: A method is provided for determining the ion component following a combustion process in a self-igniting internal combustion engine. At least two electrodes are located inside at least one cylinder, to which electrodes an electrical voltage can be applied, with the voltage being an AC voltage or having an AC voltage component.

Abstract: A circuit for monitoring and diagnosing an oxygen probe provided with a sensitive cell connected between a first and a second signal terminal, and a heating member connected between a battery and a heating terminal; the circuit comprises an interface stage and a control unit. The interface stage comprises a first resistor connected between a switch which is normally open and a supply line at a known potential and the first signal terminal, a second resistor connected between the first signal terminal and a second signal terminal and a third resistor connected between the second signal terminal and a reference potential line. The control unit further comprises a first analog-digital converter connected to the first signal terminal and a second analog-digital converter connected to the second signal terminal.

Abstract: An ion mobility sensor which can detect both ion and molecules simultaneously. Thus, one can measure the relative arrival times between various ions and molecules. Different ions have different mobility in air, and the ion sensor enables measurement of ion mobility, from which one can identify the various ions and molecules. The ion mobility sensor which utilizes a pair of glow discharge devices may be designed for coupling with an existing gas chromatograph, where various gas molecules are already separated, but numbers of each kind of molecules are relatively small, and in such cases a conventional ion mobility sensor cannot be utilized.

Abstract: A device for contactless measurement of a particle state variable of a flowing medium that contains electrically charged particles is disclosed, in which a sheet-like sensor element is disposed parallel to the particle flight direction, or at least two sensor elements, such as electrodes, are disposed in succession in the flow direction. At these electrodes, by means of the electrically charged particles flying past, charges are influenced, from which voltage signals can be generated with the aid of suitable amplifiers. To determine the particle concentration, the voltage alternation component is evaluated; to determine the particle velocity, the transport time &tgr; is evaluated; and to determine the particle throughput, both the signal height and the chronological displacement of the individual signals from one another are evaluated.

Abstract: A discharge ionization detector (DID) includes a sensor that uses an alternating current (AC) discharge through a working gas as an ionization source. The sensor includes a discharge chamber, into which the working gas is introduced, and an ionization chamber, into which a sample gas is introduced. UV photons from the discharge chamber and metastable particles that enter the ionization chamber from the discharge chamber ionize molecules in the sample gas. The ions generated from the ionized sample gas are measured as a current indicating the quantity of ionizable molecules in the sample gas. For selective identification of molecules in the sample gas, one or more chemical filters can filter the sample gas to separate target gases from gases that interfere with detection of the target gases. Additionally, a supply for the working gas can change the working gas to change the maximum energy available for ionization of the sample gas.

Abstract: A method and apparatus that provides in-situ monitoring of both the ion flux and the ion energy distribution of plasma processes to determine the endpoint of the etch process or the integrity and reproducibility of the deposition process where ion bombardment and energy distribution play critical roles in the process. A capacitance sensor is provided for measuring ion flux and ion distribution. At least one capacitance sensor is disposed within a plasma reactor at a first position for detecting ion flux emanating from a plasma within the plasma reactor. The capacitance sensor generates an ion flux measurement signal in response to the detection of the ion flux. Each of the at least one capacitance sensors is coupled to signal lines for routing an ion flux measurement signal outside the plasma reactor. A plurality of capacitance sensors may be formed as one of a plurality of rows of parts to be processed.

Abstract: Particles in a fluid cause an arc at a certain electric field whose value depends on the nature of the particles (size, composition, and the like). By applying an electric field across the fluid and determining the value of the electric field at which the arc occurs, the nature of the particles can be determined. For example, if their composition is known, their size can be determined, and vice versa. The device for carrying out such testing has a first electrode with an interior opening and a second electrode having a pin through the interior opening to define a passageway for the fluid. The electric field is varied, either by varying a voltage applied between the electrodes or by forming the passageway to be tapered. Multiple such passageways can be provided, as by forming the first electrode from honeycomb-expanded metal, thus reducing pressure drop, energy consumption without decreasing sensitivity to low concentrations.

Abstract: A gaseous fluorine detection system is provided which includes a generally enclosed sample cell containing a substrate comprising a material which interacts with fluorine gas to generate radiant energy. A gas sample of fluorine, the concentration levels of which are to be evaluated is flowed through the cell. A photomultiplier tube is positioned to receive the resulting radiant energy and generate an electrical output signal related to the level of said radiant energy. Means are provided for measuring the said photomultiplier output signal and relating same to the fluorine concentration of the gas sample provided to the cell.

Abstract: A multiple-channel photo-ionization detector (PID) determines the concentrations of specific gases or classes of gases. The PID includes a UV lamp, an optical window which is divided into multiple zones with each zone producing a UV light beam having a distinctive maximum photon energy. The ionization chamber of the PID includes multiple ion detectors. The PID measures ionization currents and concentrations of gases ionizable by each UV light beam. A method of determining the concentrations and/or identifications of the individual component gases uses differences and/or ratios of measured concentrations or currents.

Abstract: A dual-channel photo-ionization detector (PID) and a method for calculating the gas concentration in the PID are disclosed. The PID includes a UV light source which produces a UV light to ionize a gas, first and second identical ion detectors for measuring first and second currents including ion, and a UV shield which differentially shields the ion detectors from the UV light. The differential shielding of the ion detectors enables the PID to differentiate between current caused by ions and current caused by the photoelectric effect of the UV light. The detector measures a concentration of the gas irrespective of a variation of an intensity of the UV light. A heater in the PID stabilizes the temperature for measurements and prevents condensation in the PID.

Abstract: An improved tomographic technique for determining the power distribution of an electron or ion beam using electron beam profile data acquired by an enhanced modified Faraday cup to create an image of the current density in high and low power ion or electron beams. A refractory metal disk with a number of radially extending slits, one slit being about twice the width of the other slits, is placed above a Faraday cup. The electron or ion beam is swept in a circular pattern so that its path crosses each slit in a perpendicular manner, thus acquiring all the data needed for a reconstruction in one circular sweep. The enlarged slit enables orientation of the beam profile with respect to the coordinates of the welding chamber. A second disk having slits therein is positioned below the first slit disk and inside of the Faraday cup and provides a shield to eliminate the majority of secondary electrons and ions from leaving the Faraday cup.

Abstract: A plasma monitoring apparatus for monitoring a condition of plasma of a plasma load to which power is supplied from a high frequency power source through an impedance matcher provides with a first input impedance calculator for calculating an impedance as a first input impedance from a supply-side terminal of the matcher to the plasma load-side based on voltage, current and phase difference detected at the supply-side terminal of the matcher, a second input impedance calculator for calculating an impedance as a second input impedance from a load-side terminal of the matcher to the plasma load based on a impedance of a element of the matcher and the first input impedance and a plasma impedance calculator for calculating an impedance of the plasma load from the second input impedance and an impedance of a supply-side connecting the matcher and the plasma load.

Abstract: A composite alcohol testing pen includes a lower barrel (1), an upper barrel (2) and a gas detection device (3) The upper barrel (2) has a switch (21) and a light emitting diode (2) located at the outer surface, and a circuit board (4) and a battery (7) located inside. The circuit board (4) has an analyzing unit for analyzing alcohol concentration. The gas detection unit (3) receives breathing air from an users and detects the alcohol concentration contained therein.

Abstract: A static electricity measuring system including a probe, a measuring device, and a calibration device. The probe includes a sensor which detects an electric field and outputs signals representing the detected electric field. The measuring device measures static electricity on the basis of the signals output from the sensor. The calibration device generates a reference electric field. The measuring device is adjusted when the sensor detects the reference electric field produced by the calibration device.

Abstract: A gas sensor measuring a given component content in a gas is provided which has an outer and an inner metallic cover, a sensing unit, and an insulator. The sensing unit consists of a measuring electrode to be exposed to the gas to be measured and a reference electrode to be exposed to a reference gas in a reference gas chamber. The measuring electrode and the reference electrode are disposed adjacent each other through a solid electrolyte body. The inner metallic cover is installed on an end of a sensor housing. The outer metallic cover is installed on the periphery of the inner metallic cover. The insulator is mounted within the inner metallic cover and has formed therein holes through which sensor signal pickup leads pass. The insulator has an outer wall different in geometry from an inner wall of the inner metallic cover to define a portion of a reference gas passage therebetween which leads to the reference gas chamber.

Abstract: A method and apparatus for detecting a contaminant in a substrate. An array of anode elements is positioned in proximity to the substrate and is biased at a positive voltage relative to the substrate. The substrate is irradiated with photons having energies below an atomic ionization energy of the substrate, so as to ionize the contaminant to emit electrons. The emitted electrons are collected at one or more of the anode elements, thereby generating a current indicative of the presence of the contaminant in the semiconductor in proximity to the one or more of the anode elements.

Abstract: A plasma process end point determination method comprises the steps of measuring a physical quantity in a circuit for producing a plasma within a reaction chamber, and determining a plasma process end point on the basis of an inflection point of the measured physical quantity in relation to the passing of time.

Abstract: The invention relates to a circuit for measuring the electrode current of a ceramic gas sensor for measuring a gas. The ceramic gas sensor has first and second sensor electrodes arranged in a heatable ceramic and the first sensor electrode functions as a measuring electrode and the second sensor electrode functions as a reference electrode.

Abstract: The invention provides a method for predicting a process surface profile that a given plasma process will create on a process substrate. The prediction is based on a test surface profile, the experimental outcome of a test process which is in general different from the plasma process of interest. In another aspect, the invention provides a technique for defining a plasma process that will produce a desired surface profile. Thus, in related aspects, the invention also provides apparatus for predicting a process surface profile and determining process values, a method of configuring a plasma reactor, a method of making semiconductor devices requiring limited empirical calibration, and a device made according to the method.

Abstract: A method and apparatus are set forth which enables a gas chromatographic column output to be connected with a pulse discharge chamber in which chemically bound chlorine in volatile organic or inorganic samples is measured. A spark discharge is formed in the chamber to ionize and excite helium molecules to a metastable state. In turn, that transfers excitation to a trace of krypton gas in the chamber which is ionized, and the ionized krypton then preferentially binds with chemically bound chlorine. The latter binding occurs with the liberation of a photon centered at about 222 nanometers thereby defining a spectral region of interest which is measured by a photomultiplier tube to quantify chemically bound chlorine.

Abstract: An ion current detection device is disclosed that is designed to hold an ion current output voltage within a prescribed limit to ensure proper operation of a processing device connected to the output side thereof, while, at the same time, shortening the decay time of the LC resonance associated with an ignition coil. An ion current flows from one end of a capacitor and back to the other end thereof passing through an ignition coil secondary winding, a spark plug, an ion current detecting resistor, and a load resistor. A voltage equal to -(ion current value).times.detecting resistor value appears at a node between the ion current detecting resistor and the load resistor. This voltage is inverted by an inverting circuit and supplied as an ion current output to the processing circuit.

Abstract: An ionization detector for detection of an analyte includes a source chamber having a source of ionizing particles and receiving a fluid stream of detector gas; an ionization chamber connected to the source chamber at an ionization chamber entrance therebetween so as to allow metastables and photons to be generated in the source chamber and to be transferred in the fluid stream to the ionization chamber; a signal electrode assembly located in the ionization chamber; and a signal measuring circuit for measuring ionized analyte molecules. The signal electrode assembly includes a spaced array of electrodes including a collector electrode, a first signal electrode, and a second signal electrode. The first signal electrode is situated immediately downstream from the ionization chamber entrance and substantially upstream of the collector electrode, so as to extend the detection zone to the vicinity of the ionization chamber entrance.

Abstract: A chemical sensor comprising a gas detector having first and second printed wiring boards with opposed separated pairs of signal and grounded counter electrodes and processing electronics for processing ionic current signals derived from the signal and counter electrodes. A corona discharge source is provided that produces an ionized air stream containing a chemical that is to be detected. An insulating plate is disposed between the second printed wiring board of the gas detector and the corona discharge source that is used to electrically isolate the electrodes and processing electronics of the gas detector from the corona discharge source. An air flow passage is formed through the corona discharge source, the insulating plate, and the gas detector that allows the ionized air stream generated by the corona discharge source to flow past the signal and counter electrodes, so that the chemical may be detected.

Abstract: An ion current detection apparatus for an internal combustion engine includes a voltage limiting device for limiting an amount of counterelectromotive force of a primary coil of ignition coil applied to switching elements, a capacitor for applying an ion current detection voltage to a spark plug, and an ion current detection circuit for detecting an ion current wherein the capacitor is connected to the voltage limiting device.

Abstract: A combustion state detecting apparatus for an internal combustion engine is capable of ensuring a satisfactory ion current detection sensitivity and reliability by preventing discharge of bias voltage to an ignition coil to thereby protect the bias voltage against lowering.

Abstract: A method for performing a bakeout test on a vacuum chamber without causing the ion gauge to fail turns the ion gauge off when it is not needed, even during part of the time that the chamber is held at a high vacuum, so as to minimize the opportunity for contaminants to react with and damage the ion gauge filament. Specifically, the method turns the gauge off when any heating elements in the chamber are turned on, so the added heat does not exacerbate the problems with reactions with the filament. Thus, the method turns the gauge off when the chamber is too hot. In one embodiment, the method employs a heating jacket to keep the gauge and its adapter from forming a cold spot at which water vapor can condense during part of the test.

Abstract: There is provided a detector for detecting conductive contaminants entrained in an airflow. The detector comprises first and second electrically conductive meshes mounted in a spaced apart relationship to provide an operational gap. Each of the meshes is sized to provide a relatively large surface for substantially intersecting the airflow and is sufficiently porous so as not to substantially attenuate the airflow. The meshes form part of an energizable electric circuit wherein the operational gap constitutes a discontinuity of the circuit. The detector includes a capacitor connected in parallel to the portion of the circuit containing the operational gap for releasing a charge stored in the capacitor through the circuit discontinuity when one of the conductive contaminants simultaneously contacts the first and second meshes. The detector further provides for indication of a discharge of the capacitor and thereby the presence of one of the airborne conductive contaminants entrained in the airflow.

Abstract: A mechanism is provided for reducing contamination of the interior of an apparatus by a sample and for performing a stable measurement. An ion lens has an Einzel lens for converging an ion beam, a deflector for deflecting the ion beam and a pair of compensation electrodes each composed of one or more elements. A mechanism is provided for controlling a voltage to be applied to each of the electrodes as desired. Also, alternatively, a shield plate is provided in a flow path of the ion beam. A drive mechanism is provided for projecting and retracting the shield plate. With such an arrangement, it is possible not only to effectively detect a small amount of impurities contained in a sample but also to stably measure the concentration thereof.

Abstract: ECD with a non-radioactive electron source for generation of ions in a reaction chamber. The reaction chamber consists of two partial chambers, of which one is evacuated and contains the electron source, and the other contains connections for the feeding in of analysis gas as well as a collector electrode for detecting ions. The partition between the two partial chambers is permeable for electrons from the source but impermeable for gas molecules. The electron source may be a thermoemitter or a photocathode, which is irradiated from the outside through a window. In this way, contact between the analysis substance and the electron source is prevented, which increases measurement stability.

Abstract: A scanning differential mobility analysis system having a charging device, a scanning differential mobility analyzer, a flow control, and a particle detector. The charging probability and the flow rates can be dynamically adjusted according to the instant size of the particles under measurement.