5068 results about "Electron bunches" patented technology

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.

Provided is a process for preparing graphene on a SiC substrate, based on metal film-assisted annealing, comprising the following steps: subjecting a SiC substrate to a standard cleaning process; placing the cleaned SiC substrate into a quartz tube and heating the quartz tube up to a temperature of 750 to 1150° C.; introducing CCl4vapor into the quartz tube to react with SiC for a period of 20 to 100 minutes so as to generate a double-layered carbon film, wherein the CCl4 vapor is carried by Ar gas; forming a metal film with a thickness of 350 to 600 nm on a Si substrate by electron beam deposition; placing the obtained double-layered carbon film sample onto the metal film; subsequently annealing them in an Ar atmosphere at a temperature of 900 to 1100° C. for 10-30 minutes so as to reconstitute the double-layered carbon film into double-layered graphene; and removing the metal film from the double-layered graphene, thereby obtaining double-layered graphene. Also provided is double-layered graphene prepared by said process.

The present invention relates to photoresist monomers, polymers formed therefrom and photoresist compositions suitable for photolithography processes employing a DUV light source, such as KrF (249 nm) and ArF(193 nm); EUV; VUV; E-beam; ion-beam; and X-ray. Photoresist monomers of the present invention are represented by the following Chemical Formula 1: wherein, m is 1 or 2.Polymers of the present invention comprise repeating units derived from the comonomer of Chemical Formula 1, preferably together with monomers of the following Chemical Formula 2: wherein,R* is an acid-labile group, andl is 1 or 2.

A process and apparatus for free form fabrication of a three-dimensional work piece comprising (a) feeding raw material in a solid state to a first predetermined location; (b) depositing the raw material onto a substrate as a molten pool deposit under a first processing condition; (c) monitoring the molten pool deposit for a preselected condition; (d) comparing information about the preselected condition of the monitored molten pool deposit with a predetermined desired value for the preselected condition of the monitored molten pool deposit; (e) solidifying the molten pool deposit; (f) automatically altering the first processing condition to a different processing condition based upon information obtained from the comparing step (d); and repeating steps (a) through (f) at one or more second locations for building up layer by layer a three-dimensional work piece. The apparatus is characterized by a detector that monitors a preselected condition of the deposited material and a closed loop electronic control device for controlling operation of one or more components of the apparatus in response to a detected condition by the detector.

The present invention relates to a method for forming a three-dimensional article through successively depositing individual layers of powder material that are fused together so as to form the article, said method comprising the steps of: providing at least one electron beam source emitting an electron beam for heating and / or fusing said powder material. Controlling the electron beam source in a first mode when said formation of said three dimensional article is in a first process step. Controlling said electron beam in a second mode when said formation of said three dimensional article is in a second process step, wherein in said first mode an electron beam current from said electron beam source is controlled in a feed-forward mode and in said second mode said electron beam current is controlled in a feed-back mode.

An embodiment of a method of suspending a graphene membrane across a gap in a support structure includes attaching graphene to a substrate. A pre-fabricated support structure having the gap is attached to the graphene. The graphene and the pre-fabricated support structure are then separated from the substrate which leaves the graphene membrane suspended across the gap in the pre-fabricated support structure. An embodiment of a method of depositing material includes placing a support structure having a graphene membrane suspended across a gap under vacuum. A precursor is adsorbed to a surface of the graphene membrane. A portion of the graphene membrane is exposed to a focused electron beam which deposits a material from the precursor onto the graphene membrane. An embodiment of a graphene-based structure includes a support structure having a gap, a graphene membrane suspended across the gap, and a material deposited in a pattern on the graphene membrane.

Combination of nanolithography and wet chemical etching including the fabrication of nanoarrays of sub-50 nm gold dots and line structures with deliberately designed approximately 12-100 nm gaps. These structures were made by initially using direct write nanolithography to pattern the etch resist, 16-mercaptohexadecanoic acid (MHA), on Au / Ti / SiOx / Si substrates and then wet chemical etching to remove the exposed gold. These are the smallest Au structures prepared by a wet chemical etching strategy. Also, Dip-Pen Nanolithography (DPN) has been used to generate resist layers on Au, Ag, and Pd that when combined with wet chemical etching can lead to nanostructures with deliberately designed shapes and sizes. Monolayers of mercaptohexadecanoic acid (MHA) or octadecanethiol (ODT), patterned by DPN, were explored as etch resists. They work comparably well on Au and Ag, but ODT is the superior material for Pd. MHA seems to attract the FeCl3 etchant and results in nonuniform etching of the underlying Pd substrate. Dots, lines, triangles and circles, ranging in size from sub-100 to several hundred nm have been fabricated on these substrates. These results show how one can use DPN as an alternative to more complex and costly procedures like electron beam lithography to generate nanostructures from inorganic materials.

A process (and apparatus for performing the process) for layer manufacturing a three-dimensional work piece comprising the steps of; feeding raw material in a solid state to a first predetermined location; exposing the raw material to an electron beam to liquefy the raw material; depositing the raw material onto a substrate as a molten pool deposit, the deposit having a forward edge region in an x-y plane with a forward edge region width and a trailing edge region in the x-y plane with a trailing edge region width, under at least one first processing condition; monitoring the molten pool deposit for at least one preselected condition using detecting of scatter from a scanning electron beam contemporaneously with the depositing step; solidifying the molten pool deposit; automatically altering the first processing condition to a different processing condition based upon information obtained from the comparing step; and repeating steps at one or more second locations for building up layer by layer, generally along a z-axis that is orthogonal to the x-y plane, a three-dimensional work piece.

This invention relates to components useful for medical articles, such as a syringe assembly, having sliding surface(s) coated with a composition including organopolysiloxane(s), the coating being adhered to the surface(s) of the component by crosslinking induced by oxidative treatment and irradiation with an isotope, electron beam or ultraviolet radiation or heat treatment; medical articles including the same; methods to reduce static and kinetic friction between slidable surfaces; and articles of low friction prepared thereby.

Methods, and structures formed thereby, are disclosed for forming laterally grown structures with nanoscale dimensions from nanoscale arrays which can be patterned from nanoscale lithography. The structures and methods disclosed herein have applications with electronic, photonic, molecular electronic, spintronic, microfluidic or nano-mechanical (NEMS) technologies. The spacing between laterally grown structures can be a nanoscale measurement, for example with a spacing distance which can be approximately 1-50 nm, and more particularly can be from approximately 3-5 nm. This spacing is appropriate for integration of molecular electronic devices. The pitch between posts can be less than the average distance characteristic between dislocation defects for example in GaN (ρ=1010 / cm2→d=0.1 μm) resulting an overall reduction in defect density. Large-scale integration of nanoscale devices can be achieved using lithographic equipment that is orders of magnitude less expensive that that used for advanced lithographic techniques, such as electron beam lithography.

A high resolution and high data rate spot grid array printer system is provided, wherein an image representative of patterns to be recorded on a reticle or on a layer of a semiconductor die is formed by scanning a substrate with electron beams. Embodiments include a printer comprising an optical radiation source for irradiating a photon-electron converter with a plurality of substantially parallel optical beams, the optical beams being individually modulated to correspond to an image to be recorded on the substrate. The photon-electron converter produces an intermediate image composed of an array of electron beams corresponding to the modulated optical beams. A de-magnifier is interposed between the photon-electron converter and the substrate, for reducing the size of the intermediate image. A movable stage introduces a relative movement between the substrate and the photon-electron converter, such that the substrate is scanned by the electron beams.

A closed-loop control method for an electron beam freeform fabrication (EBF3) process includes detecting a feature of interest during the process using a sensor(s), continuously evaluating the feature of interest to determine, in real time, a change occurring therein, and automatically modifying control parameters to control the EBF3 process. An apparatus provides closed-loop control method of the process, and includes an electron gun for generating an electron beam, a wire feeder for feeding a wire toward a substrate, wherein the wire is melted and progressively deposited in layers onto the substrate, a sensor(s), and a host machine. The sensor(s) measure the feature of interest during the process, and the host machine continuously evaluates the feature of interest to determine, in real time, a change occurring therein. The host machine automatically modifies control parameters to the EBF3 apparatus to control the EBF3 process in a closed-loop manner.

A vinyl-group-containing dendrimer useful in coating and printing and is curable by any one of conventional triggers such as heating, ultraviolet light, infrared light, electron beams and gamma rays, the composition comprising a vinyl-group-containing dendrimer (A) comprising a core portion, branching portions, branches and at least 4 terminal portions and having a vinyl group as a terminal portion and a long-chain group and a curable unsaturated-group-containing compound (B), and the composition comprising a vinyl-group-containing dendrimer (A) obtained by reacting a polyfunctional compound (a) having at least three active-hydrogen-containing groups in a terminal per molecule and having at least five active hydrogen atoms per molecule with a long-chain-group-containing compound (b) having a functional group reactive with an active hydrogen atom so as to leave part of the active hydrogen atoms, thereby obtaining a long-chain-group-containing multi-branched compound (X), and reacting the long-chain-containing multi-branched compound (X) with a vinyl-group-containing compound (c) having a functional group reactive with an active hydrogen atom and a curable unsaturated-group-containing compound (B).

The invention is to a dual beam process for providing an ion-conducting membrane with a thin metal or metal-oxide film. The process includes the cleaning of a membrane surface with a low energy electron beam followed by the deposition of the metal or metal-oxide film by a high energy electron beam of ions.

A one-step process using electron beam radiation to polymerize pressure sensitive adhesives on web from acrylate emulsions is disclosed. The radiation may be supplied in a single or multiple dose. Products using such pressure sensitive adhesives are also disclosed.

A medical article is provided including a chamber formed from a cyclic polyolefin having an inner surface in sliding engagement with an exterior surface of a sealing member, the inner surface of the chamber being coated with a first organopolysiloxane having a viscosity ranging from about 5,000 centistokes to about 100,000 centistokes; and a sealing member having an exterior surface coated with a second organopolysiloxane having a viscosity ranging from about 10,000 centistokes to about 500,000 centistokes, the coatings being adhered to the surfaces by crosslinking induced by irradiation with an isotope, electron beam, or ultraviolet radiation, as well as methods of reducing breakloose force, sustaining force, and / or sticktion between engaging surfaces in such articles.

A method for increasing the resolution when forming a three-dimensional article through successive fusion of parts of a powder bed, said method comprising providing a vacuum chamber, providing an electron gun, providing a first powder layer on a work table inside said vacuum chamber, directing an electron beam from said electron gun over said work table causing the powder layer to fuse in selected locations to form a first cross section of said three-dimensional article, providing a second powder layer on said work table, directing the electron beam over said work table causing said second powder layer to fuse in selected locations to form a second cross section of said three-dimensional article, reducing the pressure in the vacuum chamber from a first pressure level to a second pressure level between the providing of said first powder layer and said second powder layer.

The present invention relates to technology and apparatus with high energy beam to sinter or melt and deposit material successively to realize laminated solid manufacture. The present invention features that the electronic beam scan controller controls the electronic beam to scan fast in pattern projection mode for heating powder homogeneously. Each scanning of the electronic beam has short time in the selected area, so that the scan initiating point has no great temperature change generated during the whole scanning course. Through one or several frames of scanning, the material in the forming area has temperature synchronously raised to reach the sintering or re-melting temperature for deposition onto the forming area before synchronous cooling. The present invention has greatly reduced heat stress and raised forming precision and quality.

The invention discloses equipment for manufacturing a large-size metal part in a high energy beam additive manufacturing mode and a control method of the equipment. The equipment comprises a work cavity, a worktable, a control system, a high energy beam scanning generator, a powder storage hopper, a powder laying device and a gas purification module, wherein the worktable is composed of a forming cylinder and a powder recycling cylinder, and the upper surface of the forming cylinder and the upper surface of the powder recycling cylinder are coplanar and form a work plane. The control system controls the high energy beam scanning generator and the powder laying device to move opposite to the worktable in the powder laying direction. The equipment for manufacturing the large-size metal part in the high energy beam additive manufacturing mode and the control method of the equipment largely shorten the waiting time caused by pre-installation of a powder bed when a common laser / electron beam selective melting technology is used for processing a part, thereby obviously improving the forming efficiency of high energy beam additive manufacturing. Through the application of the equipment for manufacturing the large-size metal part in the high energy beam additive manufacturing mode and the control method of the equipment, a metal part with a meter-grade size, high performance, high accuracy and a complex structure can be manufactured efficiently and rapidly.

X-ray pixel beam array systems and methods for electronically shaping radiation fields and modulating radiation field intensity patterns for radiotherapy are disclosed. One exemplary pre-clinical system may include addressable electron field emitters (102, 104) that are operable to emit a plurality of electron pixel beams (106, 108, 110). Each electron pixel beam may correspond to an x-ray target (124) and x-ray pixel beam collimation aperture (136, 138) to convert a portion of energy associated with the electron pixel beam to a corresponding x-ray pixel beam (140, 142). Further, the x-ray pixel beam array collimator (130) forms a one-to-one correspondence between individual electron pixel beam and its corresponding x-ray pixel beam. One exemplary clinical system may include a high-energy electron source (1203), an n-stage scanning system (1210), x-ray pixel beam targets (1212), and an x-ray pixel beam array collimator (1214). A controller (1206) may sequentially direct electron beam pulses to predetermined x-ray pixel targets and produce an electronically controlled radiation field direction, pattern; and intensity pattern.

A medical accelerator system is provided for simultaneous radiation therapy to all treatment fields. It provides the single dose effect of radiation on cell survival. It eliminates the inter-field interrupted, subfractionated fractionated radiation therapy. Single or four beams S-band, C-band or X-band accelerators are connected to treatment heads through connecting beam lines. It is placed in a radiation shielding vault which minimizes the leakage and scattered radiation and the size and weight of the treatment head. In one version, treatment heads are arranged circularly and connected with the beam line. In another version, a pair of treatment heads is mounted to each ends of narrow gantries and multiple such treatment heads mounted gantries are assembled together. Electron beam is steered to all the treatment heads simultaneously to treat all the fields simultaneously. Radiating beam's intensity in a treatment field is modulated with combined divergent and pencil beam, selective beam's energy, dose rate and weight and not with MLC and similar devices. Since all the treatment fields are treated simultaneously the dose rate at the tumor site is the sum of each of the converging beam's dose rate at depth. It represents the biological dose rate. The dose rate at d-max for a given field is the individual machine dose rate. Its treatment options includes divergent or pencil beam modes. It enables to treat a tumor with lesser radiation toxicities to normal tissue and higher tumor cure and control.

An electron beam inspection system of the image projection type includes a primary electron optical system for shaping an electron beam emitted from an electron gun into a rectangular configuration and applying the shaped electron beam to a sample surface to be inspected. A secondary electron optical system converges secondary electrons emitted from the sample. A detector converts the converged secondary electrons into an optical image through a fluorescent screen and focuses the image to a line sensor. A controller controls the charge transfer time of the line sensor at which the picked-up line image is transferred between each pair of adjacent pixel rows provided in the line sensor in association with the moving speed of a stage for moving the sample.

A process and apparatus for free form fabrication of a three-dimensional work piece comprising (a) feeding raw material in a solid state to a first predetermined location; (b) depositing the raw material onto a substrate as a molten pool deposit under a first processing condition; (c) monitoring the molten pool deposit for a preselected condition; (d) comparing information about the preselected condition of the monitored molten pool deposit with a predetermined desired value for the preselected condition of the monitored molten pool deposit; (e) solidifying the molten pool deposit; (f) automatically altering the first processing condition to a different processing condition based upon information obtained from the comparing step (d); and repeating steps (a) through (f) at one or more second locations for building up layer by layer a three-dimensional work piece. The apparatus is characterized by a detector that monitors a preselected condition of the deposited material and a closed loop electronic control device for controlling operation of one or more components of the apparatus in response to a detected condition by the detector.

A dual filament x-ray tube assembly (16) includes an evacuated envelope (52) having an anode (54) disposed at a first end of the evacuated envelope (52) and a cathode assembly (62) disposed at a second end of the evacuated envelope (52). The cathode assembly includes a variable-length filament assembly (72, 74; 100) which emits electron beams for impingement on the anode (54) at focal spots having varying lengths. The cathode assembly (62) further includes a cathode cup (64, 66, 68; 110, 112) which is subdivided into a plurality of electrically insulated deflection electrodes (64, 66, 68; 110, 112). A filament select circuit (80) selectively and individually heats a portion of the variable-length filament assembly (72, 74). Electron beams emitted from the filament assembly (72, 74) are electrostatically focused and controlled by applying potentials to different ones of the deflection electrodes (64, 66, 68; 110, 112). The x-ray tube assembly (16) provides longer focal spots for thick-slice scanning applications and shorter focal spots for thin-slice scanning applications along with the benefit of electrostatic focusing and control.