1693 results about "Electron source" patented technology

A novel field emitter material, field emission electron source, and commercially feasible fabrication method is described. The inventive field emission electron source produces reliable electron currents of up to 400 mA / cm2 at 200 volts. The emitter is robust and the current it produces is not sensitive to variability of vacuum or the distance between the emitter tip and the cathode. The novel emitter has a sharp turn-on near 100 volts.

The present invention is directed to a gas line electron beam exciter, gas line electron beam excitation system and method for exciting a gas using an electron beam exciter. The electron beam exciter generally comprises a variable density electron source for generating a cloud of electrons in an electron chamber and a variable energy electron extractor for accelerating electrons from the electron chamber as an electron beam and into an effluent stream for fluorescing species in the effluent. The electron density of the electron beam is variably controlled by adjusting the excitation power applied to the variable density electron source. The electrons in the electron chamber reside at a reference electrical potential of the chamber, typically near ground electrical potential. The electron energy of the electron beam is variably controlled by adjusting an electrical potential across the variable energy electron extractor, which energizes the electrons through an extraction hole of the chamber and toward the extractor. The greater the difference in the electrical potential between the electron extractor and the electron source, the higher the energy imparted to the electrons in the electron beam. The excitation power applied to the electron source can be adjusted independently from the electron energy of the electron beam, thereby altering the electron density of the electron beam without changing the energy level of the electrons of the electron beam.

A nitride-based field effect transistor includes a substrate, a channel layer comprising InAlGaN formed on the substrate, source and drain ohmic contacts in electrical communication with the channel layer, and a gate contact formed on the channel layer. At least one energy barrier opposes movement of carriers away from the channel layer. The energy barrier may comprise an electron source layer in proximity with a hole source layer which generate an associated electric field directed away from the channel. An energy barrier according to some embodiments may provide a built-in potential barrier in excess of about 0.5 eV. Method embodiments are also disclosed.

Various embodiments of the present invention relate to a plasma electron source apparatus. The apparatus comprises a cathode discharge chamber in which a plasma is generated, an exit hole provided in said cathode discharge chamber from which electrons from the plasma are extracted by an accelerating field provided between said cathode discharge chamber and an anode, at least one plasma confinement device, and a switching mechanism for switching the at least one plasma confinement device between a first value allowing for electron extraction from the plasma and a second value prohibiting electron extraction from the plasma. Associated methods are also provided.

A structure to generate x-rays has a plurality of stationary and individually electrically addressable field emissive electron sources with a substrate composed of a field emissive material, such as carbon nanotubes. Electrically switching the field emissive electron sources at a predetermined frequency field emits electrons in a programmable sequence toward an incidence point on a target. The generated x-rays correspond in frequency and in position to that of the field emissive electron source. The large-area target and array or matrix of emitters can image objects from different positions and / or angles without moving the object or the structure and can produce a three dimensional image. The x-ray system is suitable for a variety of applications including industrial inspection / quality control, analytical instrumentation, security systems such as airport security inspection systems, and medical imaging, such as computed tomography.

A multi-column electron beam inspection system is disclosed herein. The system is designed for electron beam inspection of semiconductor wafers with throughput high enough for in-line use. The system includes field emission electron sources, electrostatic electron optical columns, a wafer stage with six degrees of freedom of movement, and image storage and processing systems capable of handling multiple simultaneous image data streams. Each electron optical column is enhanced with an electron gun with redundant field emission sources, a voltage contrast plate to allow voltage contrast imaging of wafers, and an electron optical design for high efficiency secondary electron collection.

A system and method for limiting emittance growth in an electron beam is disclosed. The system includes an emitter element configured to generate an electron beam and an extraction electrode positioned adjacent to the emitter element to extract the electron beam out therefrom, the extraction electrode including an opening therethrough. The system also includes a meshed grid disposed in the opening of the extraction electrode to enhance intensity and uniformity of an electric field at a surface of the emitter element and an emittance compensation electrode (ECE) positioned adjacent to the meshed grid on the side of the meshed grid opposite that of the emitter element and configured to control emittance growth of the electron beam.

A nitride-based field effect transistor includes a substrate, a channel layer comprising InAlGaN formed on the substrate, source and drain ohmic contacts in electrical communication with the channel layer, and a gate contact formed on the channel layer. At least one energy barrier opposes movement of carriers away from the channel layer. The energy barrier may comprise an electron source layer in proximity with a hole source layer which generate an associated electric field directed away from the channel. An energy barrier according to some embodiments may provide a built-in potential barrier in excess of about 0.5 eV. Method embodiments are also disclosed.

In a scanning electron microscope, an emitted primary electron beam is diverted by an angle of at least about 45 degrees prior to incidence with a specimen. The beam may be bent by a magnetic separator. The separator may also serve to deflect secondary electron and back scattered electrons. As the angle of emissions and reflections from the specimen is close to the angle of incidence, bending the primary electron beam prior to incidence, allows the electron source to be located so as not to obstruct the travel of emissions and reflections to suitable detectors.

A micro-miniature x-ray apparatus comprises: a first chip subassembly including a source of x-rays including both Bremsstrahlung photons and characteristic x-rays; a second chip subassembly including a filter for transmitting the characteristic x-rays and blocking the Bremsstrahlung photons; a third chip subassembly including a movable element for focusing or collimating the transmitted characteristic x-rays into a beam and means for controlling the position of the focusing element. In one embodiment, the controlling means include a micro-electromechanical system (MEMS). In another embodiment, the position of the movable element determines how the x-ray beam is steered to the focal area. In still another embodiment, the x-ray source includes a field emitter electron source and a target responsive to the electrons for generating x-rays. In this case, the x-ray beam is also steered by selectively energizing the anode segments. In yet another embodiment, the movable element includes a Fresnel zone plate; in still another embodiment it includes an array of poly-capillaries. Advantageously, our x-ray source, including its focusing, collimating and steering components, can be fabricated small enough to be mounted at the end of a catheter. In addition, in some embodiments it can also fabricated sufficiently inexpensively to be disposable after each use.

An electron energy analyzer including a curved electrostatic low-pass reflector and a high-pass electrostatic transmissive filter. The reflector comprises a curved grid, preferably ellipsoidal, and an absorber electrode placed in back of the curved grid with respect to the electron source and biased negatively to the curved grid to act as a reflective low-pass filter and a collimating optics for the reflected beam. The transmissive filter includes first and second flat grids extending across the collimated reflected beam. The second grid on the side of the first grid opposite the curved grid is biased negatively to the first grid and the absorber electrode. A field free region is created by applying the same bias to the curved grid, the first grid, and chamber sidewall sleeve. An electron detector detects all electrons passed by the second grid in an energy band in the overlap of the high-pass and low-pass bands.

The invention comprises an X-ray tomography method and apparatus used in conjunction with multi-axis charged particle or proton beam radiation therapy of cancerous tumors. In various embodiments, 3-D images are generated from a series of 2-D X-rays images; the X-ray source and detector are stationary while the patient rotates; the 2-D X-ray images are generated using an X-ray source proximate a charged particle beam in a charged particle cancer therapy system; and the X-ray tomography system uses an electron source having a geometry that enhances an electron source lifetime, where the electron source is used in generation of X-rays. The X-ray tomography system is optionally used in conjunction with systems used to both move and constrain movement of the patient, such as semi-vertical, sitting, or laying positioning systems. The X-ray images are optionally used in control of a charged particle cancer therapy system.

One embodiment relates to a method of inspecting a substrate using electrons. Mirror-mode electron-beam imaging is performed on a region of the substrate at multiple voltage differences between an electron source and a substrate, and image data is stored corresponding to the multiple voltage differences. A calculation is made of a measure of variation of an imaged aspect of a feature in the region with respect to the voltage difference between the electron source and the substrate. Other embodiments and features are also disclosed.

An electron source include a first cathode electrode disposed over a substrate and terminated to provide electrons; an emitter layer disposed over the cathode electrode and formed from one or plurality vertically aligned and mono-dispersed nano-structures that are truncated to the same length, embedded in a solid matrix and protruding above the surface for emitting electrons; an insulator disposed over the emitter layer and having one or plurality of apertures, each is self-aligned with and exposes one nano-structure in the emitter layer; and a second gate electrode disposed over the insulator, having one or plurality of apertures self-aligned with the apertures in the insulator and terminated to extract electrons from the exposed nano-structures through the apertures. The gate aperture is substantially less than one micrometer and the gated nano-structures can have a density on the order of 108 / cm2. Such an electron source can be modulated with an extra low voltage, emits electrons with high current density and high uniformity, and operates with high energy-efficiency and long lifetime.

A system generates FIR laser radiation. An electron source generates an electron beam. A grating horn interacts with the electron beam to produce the FIR laser radiation. The grating horn may comprise a flat base and a pair of grating elements attached to the base, each of the grating elements being ruled with a grating period, the grating elements oriented in phase and in substantial symmetry about a normal to the flat base.

One embodiment disclosed relates to an apparatus for reflection electron beam lithography. An electron source is configured to emit electrons. The electrons are reflected to a target substrate by portions of an electron-opaque patterned structure having a lower voltage level and are absorbed by portions of the structure having a higher voltage level. Another embodiment relates to a novel method of electron beam lithography. An incident electron beam is formed and directed to an opaque patterned structure. Electrons are reflected from portions of the structure having a lower voltage level applied thereto and are absorbed by portions of the structure having a higher voltage level applied thereto. The reflected electrons are directed towards a target substrate to form an image and expose a lithographic pattern.

A multi-beam apparatus for observing a sample with high resolution and high throughput and in flexibly varying observing conditions is proposed. The apparatus uses a movable collimating lens to flexibly vary the currents of the plural probe spots without influencing the intervals thereof, a new source-conversion unit to form the plural images of the single electron source and compensate off-axis aberrations of the plural probe spots with respect to observing conditions, and a pre-beamlet-forming means to reduce the strong Coulomb effect due to the primary-electron beam.

An image formation apparatus is disclosed which includes, within an enclosure configured by a pair of substrates placed face to face and an external frame placed between the substrates, an electron source placed on one of the pair of substrates, an image formation material placed on the other substrate, and spacers placed between the substrates, characterized in that the spacers and the external frame is conductive and device is provided for electrically connecting the spacers and the external frame so that the equipotential surfaces between the spacers and the external frame are quasi-parallel when driven.

A radiation phase contrast imaging apparatus, including a radiation emission unit having a plurality of electron sources for emitting electron beams, and a target for emitting radiation through collision of electron beam emitted from each electron source, a first grating in which grating structures for diffracting radiation are disposed periodically, a second grating in which grating structures for transmitting and shielding radiation are disposed periodically, and a radiation image detector for detecting radiation transmitted through the second grating, in which the first and second gratings are disposed in an optical axis direction of the radiation so as to be able to substantially superimpose each image of the first grating formed based on radiation corresponding to each electron source on a surface of the second grating, and the radiation corresponding to each electron source forms each phase image of the same subject on the radiation image detector.

A method and apparatus for driving an electron source in which a high-quality image display is presented by correcting a non-uniform effective current distribution caused in cold cathode elements by leakage current. A digital video signal enters a shift register where a serial-to-parallel conversion is made for each line of an image based upon a shift clock signal. One line of the image data that has been subjected to the serial-to-parallel conversion is latched in a latch circuit and then applied to a voltage modulating circuit. The latter voltage-modulates the input data and sends the modulated signal to a voltage / current converting circuit. The latter converts the voltage quantity to a current quantity, which is applied to each of the cold cathode elements of a display panel through respective column terminals. A voltage V1 is applied to the selected row wire, and a voltage V2 (V2<> V1) is applied to all other row wires, for controlling the leakage current.

A thermionic electron source includes a substrate, at least two electrodes, and a thermionic emitter. The electrodes are electrically connected to the thermionic emitter. The thermionic emitter has a film structure. Wherein there a space is defined between the thermionic emitter and the substrate.

A multi-beam apparatus for observing a sample with high resolution and high throughput is proposed. In the apparatus, a source-conversion unit changes a single electron source into a virtual multi-source array, a primary projection imaging system projects the array to form plural probe spots on the sample, and a condenser lens adjusts the currents of the plural probe spots. In the source-conversion unit, the image-forming means is on the upstream of the beamlet-limit means, and thereby generating less scattered electrons. The image-forming means not only forms the virtual multi-source array, but also compensates the off-axis aberrations of the plurality of probe spots.

Disclosed are an electron-emitting element having a large operating current at a low operating voltage and excellent operation stability, and an electron source, an image display device and the like utilizing such an electron-emitting element, and further a method of fabricating such an element with few process steps at low cost. A cold cathode member is configured utilizing hybrid particle of a first particle serving to emit electrons into the space and a second particle being in the vicinity of the first particle and serving to control the position of the first particle. In this configuration, it is preferable that the first particle have a higher electron emission efficiency than the second particle and that the second particle be conductive.

An ionizer for forming a gas-cluster ion beam is disclosed including inlet and outlet ends partially defining an ionization region traversed by a gas-cluster jet and one or more plasma electron source(s) for providing electrons to the ionizing region for ionizing at least a portion of the gas-clusters to form a gas-cluster ion beam. One or more sets of substantially linear rod electrodes may be disposed substantially parallel to and in one or more corresponding partial, substantially cylindrical pattern(s) about the gas-cluster jet axis, wherein some sets are arranged in substantially concentric patterns with differing radii. In certain embodiments, the ionizer includes one or more substantially linear thermionic filaments disposed substantially parallel to the gas-cluster jet axis, heating means, electrical biasing means to judiciously bias sets of the linear rod electrodes with respect to the thermionic filaments to achieve electron repulsion.

The invention provides a method for further increasing an inspection speed, i.e. increasing the productivity of the inspection device in an SEM manner. The inspection device which inspects the surface of a substrate images in the direction of a sample W with expected times to form crossover after an electron generated from an electron source (25*1) forms crossover. When allowing the crossover to pass through, an electron as noise is removed from an opening, the crossover is set to be expected times and adjusted to be parallel electron beams to irradiate a substrate with a desired sectional shape. The electron beam is adjusted so as to keep unevenness in electron beam illumination intensity to up to 10%. Electrons emitted from the sample W are detected by a detector (25*11).