Abstract: The present disclosure discloses an apparatus. The apparatus according to the present disclosure may include a communication interface, one or more memories, and one or more processors. The one or more processors may be configured to: control the thin-film deposition devices to execute the thin-film deposition process by accessing the memory and executing a recipe; obtain in-process thin-film state data of the thin film from the thin-film measurement result received via the communication interface during the thin-film deposition process; and derive post-process thin-film state data of the thin film from the process condition data, the sensing data, and the in-process thin-film state data using a first correlation model.

Abstract: A device for simulating intermittent arc grounding faults in a power distribution network includes a sliding rail, a first and a second support frames, an insulated electrode disk, and an electrode disk motor. The first support frame is fixed on the left side of the slide rail, and the position of the second support frame relative to the first support frame can be adjusted through the sliding rail. The second support frame is provided with an electrode disk motor for driving the insulated electrode disk to rotate. An upper and a lower conductive bars are installed on the first support frame, their adjacent ends provided with an upper and a lower arc-shaped conductor sheets, and the insulated electrode disk having two circles of conductive pillars is located between the conductor sheets. The conductor sheets are respectively installed on the side of the conductive bars close to the conductive pillar.

Abstract: A gas sensing system for an air conditioner unit is provided. The air conditioner unit includes a bulkhead that divides a cabinet into an indoor portion and an outdoor portion, and a compressor circulates refrigerant through a sealed system. An electrically protected housing is positioned within the indoor portion and defines a sensor enclosure for receiving a gas sensor for measuring a gas concentration of leaked refrigerant within the sensor enclosure. The housing includes vent apertures to permit leaked refrigerant to enter the sensor enclosure while the vent apertures are covered by filters to prevent contaminants from entering the sensor enclosure.

Abstract: A method of monitoring a heating, ventilation, and air conditioning (HVAC) system for refrigerant leak. The method includes monitoring, by a controller, operation of the HVAC system and determining, using a plurality of leak detectors, whether refrigerant within the HVAC system is leaking. Responsive to a positive determination in the determining step, receiving, by the controller, a refrigerant leak warning signal and modifying, by the controller, operation of the HVAC system to prevent the refrigerant from entering an enclosed space.

Abstract: A grounding detection apparatus, a control method thereof and a pool system are provided. The grounding detection apparatus includes a detection circuit, which includes a live line connection terminal, a neutral line connection terminal, a grounding terminal, a first impedance circuit, a sampling resistance, a differential amplifying circuit and a comparison unit; a first terminal of the first impedance circuit is connected with the live line connection terminal; a second terminal of the first impedance circuit is connected with a first terminal of the sampling resistance and a first input terminal of the differential amplifying circuit; the sampling resistance is configured to convert a sampling current to a sampling voltage; the differential amplifying circuit is configured to amplify the sampling voltage to form an amplified sampling voltage; and the comparison unit is configured to compare a threshold voltage and the amplified sampling voltage and output a comparison result.

Abstract: Mobility analyzer comprising a first electrode and a second electrode, one of said electrodes being grounded and the other of said electrodes being connectable to a high-voltage source, which analyzer further comprises an aerosol inlet and a sheath flow outlet as well as at least one sample flow channel with a sample inlet and a sample outlet, wherein the electrodes are embodied in a plastic material provided with an electrically conductive coating.

Abstract: A particle sensor uses an electrostatic particle charging section in the form of an ionization chamber. A flow sensor arrangement is used to produce a signal which is representative of the amount of gas flow between the outside of the ionization chamber and the inside of the ionization chamber. This information is indicative of the flow conditions, and can be used to determine when adverse flow conditions are present which may adversely affect the performance or lifetime of the particle sensor.

Abstract: In one general aspect, a converter circuit includes a magnetic core and a coil assembly. The coil assembly includes a primary winding assembly, a secondary winding assembly, and an auxiliary winding assembly. The primary winding assembly includes a conductive medium arranged in at least one primary winding layer. The secondary winding assembly includes a conductive medium arranged in at least one secondary winding layer. The auxiliary winding assembly includes a conductive medium arranged in at least one auxiliary winding layer. The at least one auxiliary winding layer includes an auxiliary winding layer disposed adjacent to a layer of the at least one primary winding layer and adjacent to a layer of the at least one secondary winding layer.

Abstract: The present invention provides an ionization detector having a base having an enclosed chamber. The enclosed chamber has a first end and a second end. The detector also includes a first outlet which is a source of an excitable medium. A second outlet is provided which functions a source of an analyte that is transported by a carrier gas. An ionization source for creating a discharge from said excitable medium is also provided. The collector electrode generates a time dependent current based on its interaction with ionized analytes from which the analyte may be detected.

Abstract: A current measurement circuit converts a current signal IIN into a voltage signal VOUT. The current signal IIN is transmitted via a signal line. A shield line is arranged in the vicinity of at least a part of the signal line. A non-inverting amplifier includes an operational amplifier, and the current signal IIN is input to its non-inverting input terminal. The output signal of the non-inverting amplifier is input to its inverting input terminal as a feedback signal. An inverting amplifier amplifies the output signal of the non-inverting amplifier with inversion so as to generate a voltage signal VOUT. An impedance circuit includes a feedback resistor RF between the output terminal of the inverting amplifier and the non-inverting input terminal of the operational amplifier. A guard amplifier receives the electric potential at the inverting input terminal of the operational amplifier, and applies the electric potential to the shield line.

Abstract: An electrostatic coating apparatus includes a coating gun that sprays a coating material toward a coated matter, a high-voltage application apparatus that applies a high voltage to the coating gun, a bell-side current calculation unit that calculates a bell-side current to flow from the coating gun to the coated matter, an earth-side current measurement unit that measures an earth-side current to flow from the coated matter to the earth, and an earth check unit that detects an abnormal earth state of the coated matter, depending on a magnitude relation between the bell-side current calculated at the time of electrostatic coating and the bell-side current when the earth is properly connected, and a magnitude relation between the earth-side current measured at the time of the electrostatic coating and the earth-side current when the earth is properly connected.

Abstract: Non-destructive localization of open defects in electronic devices is performed with a DC SQUID based RF magnetometer capable of sensing coherent magnetic fields up to 200 MHz and higher. RF magnetic fields (or RF current) images are correlated to conductive paths layout of the electronic device, and the open defect is pinpointed at a location of RF current disappearance on the current image. The bandwidth limitations associated with transmission line delays between SQUID circuit and readout electronic, as well as with near-field coupling between different parts of the measurement scheme, are overcome by superimposing the RF flux emanating from device under study on the modulation flux to produce at the SQUID output a binary phase modulated RF voltage, which is processed to lock the static flux, and to control modulation regime by producing an AC bias for the RF flux.

Abstract: An aging treatment is performed by using cleaning gas obtained by mixing inert gas, as an impurity, to plasma gas. Plasma generation by dielectric-barrier discharge is performed until a predetermined period of time has elapsed by applying high AC voltage to an electrode while supplying the cleaning gas to a dielectric tube from a gas inlet.

Abstract: An analysis device comprising a discharge ionization current detector, a plasma gas supply section, a sample gas supply section, a flow rate setting condition holding section and a gas flow rate setting means controller. The flow rate setting condition holding section holds, as a flow rate setting condition, a relationship between a sample gas supply flow rate from the sample gas supply section and a supply flow rate of plasma gas to be set with respect to the sample gas supply flow rate and the gas flow rate controller is configured to set a plasma gas supply flow rate from the plasma gas supply section to a flow rate according to the sample gas supply flow rate, based on the flow rate setting condition held in the flow rate setting condition holding section.

Abstract: The presently disclosed embodiments are directed to the detection and monitoring of corona effluent. The present embodiments pertain to a corona sensing device that employs a film of organic charge transporting material, as the active component in a corona effluent sensing device, that is disposed onto a patterned electrode bearing support member.

Abstract: The presently disclosed embodiments are directed to the detection and monitoring of corona effluent. The present embodiments pertain to a corona sensing device that employs a film of organic charge transporting material, as the active component in a corona effluent sensing device, that is disposed onto a patterned electrode bearing support member.

Abstract: An arrangement to detect a lightning strike in a wind turbine is provided. According to the arrangement, the wind turbines contains an ozone sensor. The ozone sensor is located close to a component of the wind turbine. The component is constructed and arranged in a way that a lightning current, which results from a lightning strike into the wind turbine, is conducted through the component. The component is constructed and arranged in a way that the lightning current results in a corona generating a certain amount of ozone gas, which is detected by the ozone sensor.

Abstract: A structure and method for monitoring extrusion failures. The structure includes: a test wire having first and second ends; first and second vias contacting first and second ends of the test wire; a first monitor structure electrically isolated from the test wire and surrounding a periphery of the test wire; and a second monitor structure over the test wire, the second monitor structure electrically isolated from the test wire, the second monitor structure extending over at least the first end of the test wire.

Abstract: Systems and methods for determining the dimensions of insulating coating sections applied to a conductive component are disclosed. The method includes providing a specimen having an insulating coating section of a first surface area and a first thickness. The method further includes conducting a test of the specimen for propagating brush discharges. If the specimen exhibits propagating brush discharges, the method further includes reducing at least one of the first surface area and the first thickness to produce at least one of a second surface area or a second thickness, or reducing a first maximum distance that any portion of the insulating coating may extend from an adjacent static dissipative feature to produced a second maximum distance. In additional embodiments, insulating coating patterns may be established on the component based on at least one of the dimensions of the second surface area, the second thickness, or the second maximum distance.

Abstract: A method for determining film continuity and growth modes in thin dielectric films includes: depositing a material on the substrate using a first value of a growth metric; depositing an amount of charge on a surface of the material; repetitively measuring a surface voltage of the material until an onset of tunneling to provide a Vtunnel (or Etunnel) value; repeating the above steps for different values of the growth metric; and comparing the Vtunnel (or Etunnel) values for different values of the growth metric to provide a measure of the continuity of the material on the substrate. The growth modes of the material can be determined by comparing the first derivative of the Vtunnel or Etunnel per growth metric curve versus the growth metric, and examining the linearity of the results of the comparison. The growth metric parameters may include thickness, time, precursor cycles, or temperature.

Abstract: A device for the measuring membrane permeability in electrical/electrochemical/photo-electrochemical fields is provided. The device is a permeation cell and a tube mounted within the cell. An electrode is mounted at one end of the tube. A membrane is mounted within the cell wherein a corona is discharged from the electrode in a general direction toward the membrane thereby generating heated hydrogen atoms adjacent the membrane. A method for measuring the effects of temperature and pressure on membrane permeability and selectivity is also provided.

Abstract: A tracer material is embedded in a component of electrical equipment to detect excessive wear of the component when it is exposed to an electrical arc. As the component wears, the tracer material becomes exposed to the electrical arc and emits electromagnetic radiation, which is monitored continuously. The tracer material is selected so that it emits electromagnetic radiation when it is exposed to an electrical arc that is distinct from electromagnetic radiation emitted by any other parts of the component. A fluorescent tracer material may also be used.

Abstract: A tracer material is embedded in a component of electrical equipment to detect excessive wear of the component when it is exposed to an electrical arc. As the component wears, the tracer material becomes exposed to the electrical arc and emits electromagnetic radiation, which is monitored continuously. The tracer material is selected so that it emits electromagnetic radiation when it is exposed to an electrical arc that is distinct from electromagnetic radiation emitted by any other parts of the component.

Abstract: A test board is selectively usable as an interface between an integrated circuit device under test (DUT), such as a ball grid array package, and an automatic test equipment (ATE), and as an interface between a calibration apparatus and the ATE. The test board includes a socket, for electrically connecting to the ATE, which includes a plurality of contact terminals which are configured to directly contact terminals of the DUT during a test operation and to directly contact probes of the calibration apparatus during a calibration operation. The test board also includes an alignment mark which is positioned adjacent the socket and which can be sensed by the calibration apparatus during the calibration operation, and a test pad which is positioned adjacent the socket and which is configured to directly contact a test probe of the calibration apparatus for checking an operational state of the calibration apparatus.

Abstract: A method is described for measuring the capacitance and the equivalent oxide thickness of an ultra thin dielectric layer on a silicon substrate in which the dielectric layer is uniform or patterned. The surface of a dielectric layer is electrically charged by a flux on ions from a corona discharge source until a steady state is reached when the corona flux is balanced by the leakage current across a dielectric. The flux is abruptly terminated and the surface potential of a dielectric is measured versus time. The steady state value of the surface potential is obtained by extrapolation of the potential decay curve to the initial moment of ceasing the corona flux. The thickness of a dielectric layer is determined by using the steady state potential or by using the value of the surface potential after a predetermined time.

Abstract: A test system and data analysis procedure are provided for use in electrophotographic printing with a whole set of characteristics determined to be important for efficiency and high quality images. The test system and data analysis procedure characterize dielectric relaxation processes in materials in terms of charge transport parameters that may include intrinsic charge density, charge mobility, and charge injection from the contact surfaces. The materials may include photoconductive drums or belts, charging rolls, developer rolls, intermediate transfer belts and output media such as paper transparencies or textiles. The apparatus consists of a charging source, a voltage detector and a current detector in an open-circuit mode of measurement. The configuration closely simulates the actual application of the materials in electrophotography and thus, can yield information more relevant for the applications.

Abstract: A method and apparatus for detecting a partial discharge in a voltage transformer, the transformer having a first voltage winding and a second voltage winding. A grounded electrostatic shield being operably attached to the transformer, preferably between the windings. A radio frequency current transformer is operably connected to the electrostatic shield wherein the partial discharge occurring within the voltage transformer is detected.

Abstract: A measuring probe for determining the physical stability of emulsions and dispersions, is constructed from a rod comprising a material which is electrically nonconductive at least on the rod surface. The rod carries at least two conductivity-measurement electrodes separated from one another along the rod. These electrodes are separately supplied with electricity via the interior of the rod at one rod end. A method for determining the physical stability of emulsions and suspensions involves placing an emulsion or dispersion a sample container, immersing a measuring probe in the filled sample container, and measuring the conductivity of the emulsion or dispersion continuously or at intervals over a given period of time using the conductivity-measurement electrodes.

Abstract: The present invention relates to a system for controlling a thin film formation process using a corona discharge measurement technique. The system includes a thin film formation system operative to form a thin film based on one or more process parameters, a corona discharge measurement system operable to measure one or more properties of the thin film, and a processor operatively coupled to the thin film formation system and the corona discharge measurement system, wherein the processor analyzes the data from the corona discharge measurement system and a set of target data and controls the one or more process parameters via the thin film formation system based on the analysis. The present invention also relates to a method for controlling a thin film formation using a corona discharge technique.

Abstract: A corona discharge apparatus includes a control unit and a discharge unit. The control unit has a baseboard with a main power source circuit located thereon. A CPU, a memory as well as other elements such as an attachment for a gas supply source are] installed in a housing of the control unit. The discharge unit has a high voltage generation circuit including a high-frequency step-up transformer installed in a housing of the discharge unit. A cable including a power line and a signal communication line is detachably connectable to the control unit and the discharge unit to electrically couple the units together through connectors secured to the respective housings. A gas guide tube is also detachably connectable to the discharge unit housing to feed a gas from the gas supply source into the discharge unit.

Abstract: A test system and data analysis procedure are provided for use in electrophotographic printing with a whole set of characteristics determined to be important for efficiency and high quality images. The test system and data analysis procedure characterize dielectric relaxation processes in materials in terms of charge transport parameters that may include intrinsic charge density, charge mobility, and charge injection from the contact surfaces. The materials may include photoconductive drums or belts, charging rolls, developer rolls, intermediate transfer belts and output media such as paper transparencies or textiles. The apparatus consists of a charging source, a voltage detector and a current detector in an open-circuit mode of measurement. The configuration closely simulates the actual application of the materials in electrophotography and thus, can yield information more relevant for the applications.

Abstract: An automated test system is provided for evaluating characteristics of photoreceptors used in the electrophotographic process. The test system includes a dielectric material support adapted to receive said dielectric material one or more electrodes adapted to apply electrical energy from a source to a two dimensional area adjacent the support for storage by the dielectric material and a sensor for the electrical energy stored in the dielectric material and providing an output representation of the dielectric relaxation of the material in response to the stored energy over the two dimensional area. This test system provides advantages over conventional Electrostatic Charge Decay (ECD) methods by eliminating corona pre-charging and a moving detector when a full-length array is used. Also, this test system utilizes a lower cost current detector in comparison to conventionally used voltage detectors.

Abstract: A method of measuring total charge of an insulating layer on a semiconductor substrate includes applying corona charges to the insulating layer, and measuring a surface photovoltage of the insulating layer after applying each of the corona charges. The charge density of each of the corona charges is measured with a coulombmeter. A total corona charge required to obtain a surface photovoltage of a predetermined fixed value is determined and used to calculate the total charge of the insulating layer. The fixed value corresponds to either a flatband or midband condition.

Abstract: A floating plate ion monitoring system and method wherein an ion collector assembly comprises an ion conducting surface and shielding surface in spaced relation, the ion conducting surface being located to receive ion impingement thereon, and wherein a potential is applied to the shielding surface which duplicates and follows the voltage appearing on the ion conducting surface. As a result, the capacitance between the ion conducting surface and the shielding surface is established electrically and independent of the physical configuration of the ion collector assembly. The foregoing is accomplished by providing a unity gain connected operational amplifier and connecting the positive input thereof to the ion conducting surface and the inverting input thereof to the shielding surface. An indicator connected to the amplifier output monitors the voltage on the ion conducting surface.

Abstract: A corona discharge apparatus comprises a control unit and a discharge unit. The control unit has a baseboard with a main power source circuit located thereon. A CPU, a memory as well as other elements such as an attachment for a gas supply source are] installed in a housing of the control unit. The discharge unit has a high voltage generation circuit including a high-frequency step-up transformer installed in a housing of the discharge unit. A cable including a power line and a signal communication line is detachably connectable to the control unit and the discharge unit to electrically couple the units together through connectors secured to the respective housings. A gas guide tube is also detachably connectable to the discharge unit housing to feed a gas from the gas supply source into the discharge unit.

Abstract: The present invention provides a non-contact method for determining whether a contaminant is present in a semiconductor wafer having a substrate/dielectric interface formed thereon. in one advantageous embodiment, the method comprises field inducing a junction in equilibrium inversion in the semiconductor wafer device. A conventional corona source may be used to induce the junction to equilibrium inversion. This particular embodiment further includes forming a contaminant junction near the substrate/dielectric interface when the contaminant is present in the semiconductor wafer by adding charge and pulsing the junction out of equilibrium. A surface voltage measurement, which may be taken with a Kelvin probe, is obtained by measuring a change in a surface voltage as a function of time. The method further includes determining whether the contaminant is present in the semiconductor wafer from the change in the surface voltage.

Abstract: A method and an apparatus for touch-free testing of the insulating ability of an electric insulation on an electric conductor, where the testing item (8), the conductor, continuously is moved between a system of testing electrodes (2, 4), where the electric current path to the surface of the testing item is established by means of ionized atmospheric air, ion cloud or corona, between the testing electrodes (2, 4), made by a high frequenced high voltage generator (14) with low effect, where the testing item (8) is moved through the center of the electrode system (2, 4), that defects in the insulation are determined by means of a D.C. voltage established in an electric serial connection with the ion cloud, so that insulation defects in the testing item (8) will cause an electric current through the electric charge carrier in the form of ions, and that the electric current is registered by a current measuring circuit (18).

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: The present invention is directed to a system for, and method of, determining a non-contact, near-surface generation and recombination lifetimes and near surface doping of a semiconductor material. The system includes: (1) a radiation pulse source that biases a dielectric on top of the semiconductor material, (2) a voltage sensor to sense the surface voltage, and (3) a photon source to create carriers. For lifetime measurements both the excitation and measurement signals are time dependent and may be probed near the surface of the semiconductor to obtain various electrical properties. For high-field tunneling and leakage characteristics of a thin dielectric (<15 nm) on top of the semiconductor, a high bias charge density is used to induce tunneling, from which tunneling fields and charge-fluence to tunneling of the dielectric are determined.

Abstract: A testing device for detecting defects in insulation of electrosurgical instruments that includes an implement or wand having a distal end, an electrode for generating a spark adapted to detect a defect in the insulation, and mounting means for removably mounting the electrode to the distal end of the implement. The removable mounting means includes a shank that is received in a socket or bore defined in the distal end of the wand and is engageable with the wand within the socket so the shank can easily be removed from the socket after use. The wand is releasably engageable with the housing by a flexible bracket that extends from the housing. The device may include a pad having a reflective top surface with ridges upon which the surgical instrument to be tested is placed.

Abstract: This invention relates to an impulse generator which utilizes the properties of floating electrodes. An exemplary impulse generator comprises a floating electrode with a corona source, a series gap, an output terminal for connecting to a device undergoing electric impulse testing and a ground connection. The present invention generates an electric impulse signal for use in testing the impulse response or static electricity impulse response of an electronic circuit.

Abstract: Corona charge is applied to an oxide layer on a semiconductor wafer. Then ultraviolet light is used to erase a grid pattern of the corona charge. Opposite polarity corona charge is then applied to the layer, resulting in a grid of field-induced PN junctions. The surface photovoltage of the junctions is measured over time to provide a measure of the mobile charge in the oxide layer.

Abstract: A partial-discharge measuring device (3) which detects partial discharges in a gas-insulated, metal-enclosed, high-voltage system. The device includes an annular-gap antenna (6) arranged on the inner surface of the metal enclosure (1), a coaxial measuring cable (7) guided to a measuring instrument, and a tapering adaptor conductor (8) which connects the annular-gap antenna (6) and the coaxial measuring cable (7). The annular gap (9) of the antenna is determined by a plate-shaped electrode (10) which is inserted in an electrically insulated fashion into an opening (5), provided for a flanged attachment (4) in the metal enclosure (1). The adaptor conductor (8) includes an inner conductor, which supports the electrode (10), and is guided onto the shielded conductor (14) of the measuring cable (7), and an outer conductor which is guided onto the shield (15) of the measuring cable (7).

Abstract: A method for measuring the thickness of very thin oxide layers on a silicon substrate. A corona discharge source repetitively deposits a calibrated fixed charge density on the surface of the oxide. The resultant change in oxide surface potential for each charge deposition is measured. By choosing a starting value for an assumed oxide thickness, the approximate change in silicon bandbending per corona discharge step is determined. The cumulative changes in bandbending versus oxide surface potential yields an experimental bandbending versus bias characteristic. A theoretical bandbending versus bias characteristic is established. The experimental and theoretical characteristics are matched at the predetermined points thereof and then the assumed oxide thickness is iterated until both characteristics superimpose in the silicon accumulation region. The iterated oxide thickness that allows both characteristics to superimpose is the oxide thickness value being sought.

Abstract: A system and method for coincidence detection of ungrounded or inadequately grounded parts during the electrostatic coating process in order to improve production flow, provide an overall cost saving by efficient use of the coating material and prevention of accidental fires and false shutdown during production. The present invention utilizes a coincidence detection technique which performs a test for radio-frequency electromagnetic energy radiated by sparking and/or corona discharge caused by ungrounded parts outside a electrostatic coating area and a test for sensing and discriminating spurious radio-frequency electromagnetic energy radiated by sparking and/or corona discharge caused by any other external source. In accordance with one specific embodiment, the test performed outside the booth may include a further test for detecting ultraviolet energy radiated by the sparking and/or corona discharge.

Abstract: A pulsed discharge photoinoization detector is set forth which comprises a plurality of closed chambers for receiving different types of carrier gas flowing there through between inlets and outlets. The carrier gases are exposed to a pair of electrodes forming a spark across each chamber and through each carrier gas. At least one component of each type of carrier gas is excited within each chamber by the spark discharges, and the resonance energies of each type of carrier gas are different. The sample to be analyzed is split and a portion is injected into each of the closed chambers where it is exposed to the excited carrier gases. Carrier gases, upon decay, serve as sources of ionizing radiation of differing energy which react with compounds within the sample gas producing ionization currents which are a function of the types of sample gas compounds and the types of carrier gases.

Abstract: A pulsed rare gas photoionization detector apparatus is set forth and incorporates a closed chamber for receiving a carrier gas flowing there through between inlets and outlets, and the carrier gas is exposed to a pair of electrodes forming a spark across the chamber and through the carrier gas. One component of the carrier gas is a dopant which selected from a plurality of rare gases. The sample to be analyzed is injected into the closed chamber where it commingles with the carrier gas. One reaction involves the formation of selected dopant in an excited state, which upon decay, serves as a source of ionizing radiation which reacts with sample compounds producing detectable events. These events are used to identify and quantify unknown compounds contained in the sample. The methods and apparatus are especially useful in selectively ionizing the compounds to be measured while not ionizing other constituents of the sample. This greatly enhances the signal-to-noise ratio for detecting impurity compounds.

Abstract: A circular chamber is disclosed. Helium is introduced into the chamber to swirl in a circle to flow past a pair of spaced electrodes forming a spark in the helium. The chamber enables a sample detected by interaction with spark initiated ionization.

Abstract: An isolated detector for gas is set forth and incorporates a closed source chamber in cooperation with a sample chamber through which sample gas flows. Gas within the source chamber comprises Krypton which is excited to a metastable state by a pulsed, high voltage, direct current spark. Subsequent decay of metastable argon emits ionizing radiation which passes through a membrane window into the sample chamber thereby ionizing selected constituents within the sample gas. Charged particles resulting from the ionization of selected constituents are collected with voltage biased electrodes in the sample chamber, and the magnitude of the resulting current flow is related to the concentration of the ionized molecules or compounds. The apparatus for generating ionizing radiation requires no external source of gas, is rugged, is relatively inexpensive to manufacture and operate, and exhibits an operating life much longer than source lamps used in prior art devices.

Abstract: A method for measuring the thickness of very thin oxide layers on a silicon substrate. A corona discharge source repetitively deposits a calibrated fixed charge density on the surface of the oxide. The resultant change in oxide surface potential for each charge deposition is measured. By choosing a starting value for an assumed oxide thickness, the approximate change in silicon bandbending per corona discharge step is determined. The cumulative changes in bandbending versus oxide surface potential yields an experimental bandbending versus bias characteristic. A theoretical bandbending versus bias characteristic is established. The experimental and theoretical characteristics are matched at predetermined points thereof and then the assumed oxide thickness is iterated until both characteristics superimpose in the silicon accumulation region. The iterated oxide thickness that allows both characteristics to superimpose is the oxide thickness value being sought.