83results about "Tube electron sources" patented technology

An electron beam apparatus is configured for dark field imaging of a substrate surface. Dark field is defined as an operational mode where the image contrast is sensitive to topographical features on the surface. A source generates a primary electron beam, and scan deflectors are configured to deflect the primary electron beam so as to scan the primary electron beam over the substrate surface whereby secondary and/or backscattered electrons are emitted from the substrate surface, said emitted electrons forming a scattered electron beam. A beam separator is configured to separate the scattered electron beam from the primary electron beam. The apparatus includes a cooperative arrangement which includes at least a ring-like element, a first grid, and a second grid. The ring-like element and the first and second grids each comprises conductive material. A segmented detector assembly is positioned to receive the scattered electron beam after the scattered electron beam passes through the cooperative arrangement. Other embodiments, aspects and features are also disclosed. The apparatus is configured to yield good topographical contrast, high signal to noise ratio, and to accommodate a variety of scattered beam properties that result from different primary beam and scan geometry settings.

The invention discloses a femtosecond electron diffraction device that includes light resource, electron generate and control system, sample room, electron measuring and imaging system, vacuum system and five shafts control system. The electron generating and controlling system includes photo cathode, anode, magnetic lens, X direction deflecting plate and Y direction deflecting plate. The invention decreases the distance from the cathode to sample and improves the time resolving power. The invention could be used to measure the structure dynamic information of transmission diffraction and reflection diffraction of the sample.

A mass spectrometer that allows easy replacement of an MCP (microchannel plate) and is enabled to secure orthogonality between an incident surface of the MCP and an ion track at high accuracy is provided. A flight tube 2 where ions fly is arranged in a vacuum vessel composed of a vacuum flange 6 and a body 1, and an MCP group 4 is attached to a tail end of the flight tube 2 via an MCP-IN electrode 3. A vacuum flange 6 is attachably and detachably attached to the body 1, and the MCP group 4, by a spring 710 provided on a circuit board 7 for detection attached to the vacuum flange 6, is urged toward an end portion of the flight tube 2 so that its orthogonality with respect to an ion flight track is secured.

The invention relates to the linear dynamic range of ion abundance measurement devices in mass spectrometers, such as time-of-flight mass spectrometers. The invention solves the problem of ion current peak saturation by producing a second ion measurement signal at an intermediate stage of amplification in a secondary electron multiplier, e.g. a signal generated between the two multichannel plates in chevron arrangement. Because saturation effects are observed only in later stages of amplification, the signal from the intermediate stage of amplification will remain linear even at high ion intensities and will remain outside saturation. In the case of a discrete dynode detector this could encompass, for example, placement of a detection grid between two dynodes near the middle of the amplification chain. The invention uses detection of the image current generated by the passing electrons.

The invention discloses a molecular four-dimensional imaging system based on femtosecond electron diffraction. The molecular four-dimensional imaging system comprises a femtosecond electronic gun system, an ultrasonic molecular beam system, a sample room, an ion velocity imaging system, a vacuum system and a relevant correction regulating system. Femtosecond electronic impulse is obtained by high-voltage electrode acceleration and magnetic lens focus; and direct and real-time molecular diffraction images can be obtained by the action of the electronic impulse and ultrasonic molecular beams. Auxiliary analysis information such as velocity distribution and angular distribution parameters of dissociation fragments can be obtained by integrating ion velocity imaging technology, so that electronic diffraction images of complicated molecular dynamic processes can be analyzed and identified better. The four-dimensional imaging system has relatively high time resolution capability and spatial resolution capability, can analyze four-dimensional dynamic images with femtosecond time resolution and atomic-scale spatial resolution conveniently under the assist of the ion velocity imaging technology.

The present invention relates to an ion trap mass spectrometer using a cold electron source, in a production of a portable mass spectrometer, in which a microchannel plate (MCP) module is used, initial electrons are induced by injecting ultraviolet photons emitted from an ultraviolet diode to a front surface of the MCP module, electron beams amplified from the electrons are amplified using a channeltron electron multiplier (CEM), the amplified electron beams are accurately adjusted and injected into an ion trap, thus increasing the amplification rate, and since a quadrupole field is used as an ion filter which returns the initially injected electrons to the inside of an ion trap mass separator, the ionization rate increases.

In accordance with the invention, the ion source of a time-of-flight mass spectrometer includes an electron gun having an electron source and at least one electrode for conditioning the flow of electrons, followed by at least one microchannel wafer for generating a pulsed secondary electron beam containing a greater number of electrons from a pulsed primary electron beam. The secondary electron beam enters a gas ionization area of an ion gun which produces a flow of ions which is then passed through the flight tube in order to be analyzed by an ion detector. This provides a high-performance ion source which is compact, sensitive and easy to integrate.

The present invention relates to an ultraviolet diode and an atomic mass analysis ionization source collecting device using an MCP. In the manufacturing of a portable atomic mass analyzer, an object of the present invention is to use an MCP electron multiplier plate, whereby ultraviolet photons emitted from an ultraviolet diode are irradiated on a front surface plate of the MCP electron multiplier plate to induce primary electrons, an amplified electron beam is collected from the electrons, and an electron beam is generated at a low temperature and low power and having a discharge time that is accurately controlled. The atomic mass analysis ionization source collecting device using an ultraviolet diode and an MCP according to the present invention comprises: an ultraviolet diode emitting ultraviolet rays by means of supplied power; an MCP electron multiplier plate inducing and amplifying primary electron discharge from ultraviolet photons from the ultraviolet diode, and collecting a large amount of electron beams from an MCP reverse surface plate; an electron condenser lens condensing the electron beam amplified through the MCP electron multiplier plate; an ion trap atomic mass separator ionizing gas sample molecules by means of an electron beam injected through the electron condenser lens; and an ion detector performing detection of ions separated from the ion trap atomic mass separator, by means of an atomic mass spectrum.

The invention provides a cathode system for an Electron Ionization (EI) source comprising a filament and current supply posts, the current supply posts dividing the filament into segments and each current supply post supplying or returning the current for at least two segments of the filament. Each filament segment is connected, for instance by spot welding, to the supply posts delivering the heating current. The filament segments may be arranged in a row, or substantially parallel to each other. Filament segments arranged in a row may form a closed loop, for instance, a ring. Other embodiments encompass the filament shape of a helical coil.

The invention relates to a plurality of molecule components included in a gas are to be ionized at the same time by PI method. For instance, a plurality of molecule components included in a gas generated at a certain instance are accurately analyzed in real time based on PI method. A gas analyzer is provided with a gas transfer apparatus for transferring a gas generated from a sample in a sample chamber to an analyzing chamber; an ionizer for ionizing the gas; a quadruple filter for separating ions by mass/charge ratio; and an ion detector for detecting the separated ions. The ionizer is provided with an ionizing region arranged in the vicinity of a gas exhaust of the gas transfer apparatus, and a lamp for applying light on the ionizing region. Since the lamp outputs light which has light directivity lower than that of a laser beam and travels by spreading, the gas entered the ionizing region in the ionizer receives light in a wide range, and the gas components inside are ionized at the same time.

The present invention relates to a device for obtaining the ion source of a mass spectrometer using an ultraviolet diode and a CEM module, having the purpose of inducing initial electron emission using a CEM module and by radiating ultraviolet photons emitted from the ultraviolet diode to the entrance of the CEM module to obtain a large amount of amplified electron beams from the exit and to produce electron beams the emission times of which are accurately controlled at low temperature and at low power. The present invention is characterized by a device for obtaining the ion source of a mass spectrometer using an ultraviolet diode and a CEM module, the device consisting essentially of: an ultraviolet diode emitting ultraviolet rays by means of supplied power; an electron multiplier inducing and amplifying the initial electron emission of ultraviolet photons from the ultraviolet diode and obtaining a large amount of electron beams from the exit; an electron condenser lens condensing the electron beams amplified by the electron multiplier; an ion trap mass separator ionizing gas sample molecules by the electron beams injected through the electron xondensing lens; and an ion detector detecting ions separated from the ion trap mass separator by mass spectrum, wherein the electron multiplier is a CEM module.

An electron source for electron-induced dissociation in an RF-free electromagnetostatic cell for use installation in a tandem mass spectrometer is provided. An electromagnetostatic electron-induced dissociation cell may include at least one magnet having an opening disposed therein and having a longitudinal axis extending through the opening, the magnet having magnetic flux lines associated therewith, and an electron emitter having an electron emissive surface comprising a sheet, the emitter disposed about the axis at a location relative to the magnet where the electron emissive surface is substantially perpendicular to the magnetic flux lines at the electron emissive surface.

The invention relates to a mass spectrometry analyzer, in particular to an ionization source for nano array modified enhanced photoelectronic emission based on vacuum ultraviolet light. The ionization source comprises a vacuum ultraviolet light source and an ionization chamber, wherein a plurality of transmission electrodes and vacuum differential pore electrodes are arranged in parallel at intervals inside the ionization chamber; nano gold arrays are deposited on the surfaces of the pore electrodes; the heights of the nano gold arrays are about dozens and hundreds of nanometers; through holes are formed in the axis directions of the electrodes; ultraviolet light emitted from a vacuum ultraviolet light source radiates to the pore electrodes in the axial direction; direct-current voltage is respectively applied to the transmission electrodes and the pore electrodes. According to the ionization source provided by the invention, a surface plasma resonance effect of the nano gold array is utilized, the efficiency in generating photoelectron from a vacuum ultraviolet lamp can be improved, the sensitivity is improved under the condition that the light intensity of the ultraviolet lamp is not changed, and in addition, due to oxidation resistance of the gold surface self, contamination of an oxidation gas to the surface of the metal electrode is alleviated, and the stability of the ionization source is improved.

The present invention relates to an anion generating and electron capture dissociation apparatus using cold electrons, which uses an MCP electron multiplier plate for generating an electron beam for ionization within an ion trap of a Fourier transform ion cyclotron resonance mass spectroscope, injects ultraviolet photons emitted from an ultraviolet diode across the entire surface of the MCP electron multiplier plate, uses an electron focusing lens to focus and inject an electron beam into the trap, and generates an ECD reaction by coupling electrons to molecules having multiple positive charges using a low energy electron beam emitting apparatus for the negative ionization of neutral molecules in the ion trap. The anion generating and electron capturing and analyzing apparatus of the present invention, which uses cold electrons and is configured of a cold electron generating module which generates a large number of cold electrons from ultraviolet photons emitted into a mass spectroscope in a high vacuum state, comprises a plurality of ultraviolet diodes emitting ultraviolet photons in the mass spectroscope, an MCP electron multiplier plate inducing and amplifying an initial electron emission of ultraviolet photons from the ultraviolet diodes, and generating a high capacity electron beam from a back plate, an electron focusing lens for focusing the electron beam amplified through the MCP electron multiplier plate, and a grid for adjusting the energy and current of electrons.

A portable quadrupole ion trap mass spectrometer includes an electron emission source, an ion trap including a ring electrode and first and second end cap electrodes arranged opposite sides of the ring electrode, and an ion detector for detecting an amount of ions discharged from the ion trap. The first end cap electrode includes a first aperture through which the electrons emitted by the electron source enter the ion trap, and the second end cap electrode includes a second aperture through which ions are discharged the ion trap. A first electron multiplier is disposed in the first aperture of the first end cap electrode and multiplies an amount of the electrons and input to the ion trap. An ion detector detects an amount of the ions discharged from the ion trap.

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

A quadrupole is filled with ions and the ions are cooled by applying a pressure and gas flow within the quadrupole. Ions are trapped in the quadrupole by applying a DC voltage and an RF voltage to quadrupole rods of the quadrupole, one or more DC voltages to a plurality of auxiliary electrodes of the quadrupole, and a DC voltage and an RF voltage to an exit lens at the end of the quadrupole. The ions are coherently oscillated after the filling and cooling by applying a coherent excitation between at least two rods of the quadrupole rods. The coherently oscillating ions are axially ejected through the exit lens and to a destructive detector for detection by changing one or more voltages of the one or more DC voltages of the plurality of auxiliary electrodes and changing the DC voltage of the exit lens.

A probe assembly can be connected and disconnected from its electrical harness within a vacuum chamber so that the probe assembly with the work piece mounted can be rotated and tilted without interference from a cable, and can then be reconnected without opening the vacuum chamber. Also described is a means of grounding a sample and probes when the probe assembly is disconnected from its electrical harness and a means of preventing damage to the probe mechanism and the probe itself by ensuring that the probes are not sticking up too far during operations.