The present invention refers to a device for generating charged particle beams with tunable orbital angular momentum. The device firstly includes one or more components for providing a charged particle beam. It is further characterized by an electrical arrangement for imparting a tunable orbital angular momentum to the charged particle beam during operation. The orbital angular momentum of the produced charged particle vortex beam is tunable by adjusting the amount of electrical current. The chirality of the produced charged particle vortex beam is switchable by reversing the direction of the electrical current. The generation of the charged particle vortex beam from the present invention does not depend on the energy of the charged particle beams. The generation of the charged particle vortex beams from the present invention is predictable and reproducible.

The inventive concept relates to an apparatus for aging a field emission device configured to emitting electrons based on an electric field between a first electrode and a second electrode, and an aging method thereof. The apparatus according to an embodiment of an inventive concept includes a voltage generator and a current controller. The voltage generator increases the voltage applied to the first electrode to the target voltage level during the first time. The current controller increases the field emission current for the second time to the target current level and increases the pulse width of the field emission current for the third time to the target pulse width. According to the inventive concept, the performance of a large field emission device may be improved with high efficiency and low cost.

The present invention relates to a handheld material analyser comprising an air-tight chamber having an analysis aperture; an electron beam generation system adapted to direct a beam of electrons through the analysis aperture; an Energy-Dispersive X-ray (EDX) spectroscopy system having a detector located in the chamber; the chamber being adapted to operate at internal pressures between atmospheric pressure and a vacuum of the order of 1 Pa; and a gas inlet adapted to receive an inert gas for generating a plasma in the region of the photocathode. In this way, the plasma can clean the photocathode.

A photoinjector system containing modularly-structured waveguide-mode launcher, which is reversibly connected to the RF gun (containing a tubular construction formed with disattachably-affixed to one another structurally-complementary halves); and a solenoid magnet in operation enclosing such tubular structure in a central hollow. The resulting quality, power, and frequency rate of operation as well as cost of manufacturing and operation of the system are superior as compared with those of a related art system.

A chip scale encapsulated vacuum field emission device integrated circuit and method of fabrication therefor are disclosed. The vacuum field emission device is a monolithically fabricated triode vacuum field emission device, also known as a VACFET device. The VACFET device includes a substrate, a VACFET formed laterally on the substrate, and a containment shell that seals around a periphery of the VACFET and against the substrate. Preferably, the VACFET of the VACFET device includes an anode and a cathode formed on the substrate, a bottom gate and a top gate. The bottom gate is located between the anode and the cathode and the substrate, and the top gate is located above the anode and the cathode with respect to the substrate.

A field emission cathode device and method for forming a field emission cathode device involve a cathode element having a field emission surface disposed in spaced-apart relation to a gate electrode element so as to define a gap between the field emission surface and the gate electrode element. The gate electrode element extends laterally between opposing anchored ends. The gate electrode element is arranged to deform away from the field emission surface in response to heat, so as to increase the gap between the field emission surface and the gate electrode element.

An emitter (3) and a target (7) are arranged so as to face each other in a vacuum chamber (1), and a guard electrode (5) is provided at an outer circumferential side of an electron generating portion (31) of the emitter (3). The emitter (3) is supported movably in both end directions of the vacuum chamber (1) by the emitter supporting unit (4) having a movable body (40). The emitter supporting unit (4) is operated by an operating unit (6) connected to the emitter supporting unit (4). By operating the emitter supporting unit (4) by the operating unit (6), a distance between the electron generating portion (31) of the emitter (3) and the target (7) is changed, and a position of the emitter (3) is fixed at an arbitrary distance, then field emission is performed with the position of the emitter (3) fixed.

Provided herein is a field emission device. The field emission device includes a cathode which is connected to a negative power supply and emits electrons, an anode which is connected to a positive power supply and includes a target material receiving the electrons emitted from the cathode, and a ground electrode which is formed to face the anode and has an opening through which the electrons emitted from the cathode pass. The ground electrode is grounded so that when an arc discharge occurs due to high voltage operation of the anode, electric charge produced by the arc discharge is emitted to a ground.

A method of producing an electron emitting device includes: step A of providing an aluminum substrate or providing an aluminum layer supported by a substrate; step B of anodizing a surface of the aluminum substrate or a surface of the aluminum layer to form a porous alumina layer having a plurality of pores; step C of applying Ag nanoparticles in the plurality of pores to allow the Ag nanoparticles to be supported in the plurality of pores; step D of, after step C, applying a dielectric layer-forming solution onto substantially the entire surface of the aluminum substrate or the aluminum layer, the dielectric layer-forming solution containing, in an amount of not less than 7 mass % but less than 20 mass %, a polymerization product having siloxane bonds; step E of, after step D, at least reducing a solvent contained in the dielectric layer-forming solution to form the dielectric layer; and step F of forming an electrode on the dielectric layer.

A high-brightness electron beam source is disclosed. The electron beam source may include a broadband illumination source configured to generate broadband illumination. A tunable spectral filter may be configured to filter the broadband illumination to provide filtered illumination having an excitation spectrum. The electron beam source may further include a photocathode configured to emit one or more electron beams in response to the filtered illumination, wherein emission from the photocathode is adjustable based on the excitation spectrum of the filtered illumination from the tunable spectral filter.