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.

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.

An electron emission apparatus, an electron gun, and a method of fabrication of the electron gun are provided. The electron gun includes a cathode, a Wehnelt, and an anode. The cathode is configured to provide an electron beam. The Wehnelt has a bore. The bore is configured to pass the electron beam. The anode is disposed proximate to the cathode. The diameter of the bore of the Wehnelt and the offset between the Wehnelt and the cathode satisfy a predetermined dimensional relationship. The predetermined dimensional relationship is at least a function of a diameter of the bore of the anode and a distance between the Wehnelt and the anode.

A substrate processing apparatus includes a chamber, a pedestal provided in the chamber and having a substrate holding region to hold a substrate thereon, and a gas supply part to supply a gas into the chamber. A plurality of electron gun arrays two-dimensionally arranged so as to cover the substrate holding region is provided and configured to emit electrons toward the gas to cause interactions between the emitted electrons and the gas. A plurality of electron energy control parts is correspondingly provided at each of the electron gun arrays and configured to control energy of the electrons emitted from each of the electron gun arrays independently of each other.

A substrate processing apparatus includes a chamber, a pedestal provided in the chamber and having a substrate holding region to hold a substrate thereon, and a gas supply part to supply a gas into the chamber. A plurality of electron gun arrays two-dimensionally arranged so as to cover the substrate holding region is provided and configured to emit electrons toward the gas to cause interactions between the emitted electrons and the gas. A plurality of electron energy control parts is correspondingly provided at each of the electron gun arrays and configured to control energy of the electrons emitted from each of the electron gun arrays independently of each other.

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 fabrication method produces a mechanically patterned layer of group III-nitride. The method includes providing a crystalline substrate and forming a first layer of a first group III-nitride on a planar surface of the substrate. The first layer has a single polarity and also has a pattern of holes or trenches that expose a portion of the substrate. The method includes then, epitaxially growing a second layer of a second group III-nitride over the first layer and the exposed portion of substrate. The first and second group III-nitrides have different alloy compositions. The method also includes subjecting the second layer to an aqueous solution of base to mechanically pattern the second layer.

The present invention relates to an electron gun cathode mount adapted at one end to secure a thermionic cathode and at the other end to be connected to an attachment member, wherein the electron gun cathode mount is structured so as to be capable of, when in use, reducing heat transfer from the thermionic cathode to the attachment member, and the material forming the electron gun cathode mount has a thermal conductivity of less than 10 Wm.sup.?1K.sup.?1 at the operating temperature of the thermionic cathode in a direction from the thermionic cathode to the attachment member. The present invention also relates to an electron gun assembly having the electron gun cathode mount installed therein.

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.

Methods of marking paper products and marked paper products are provided. Some methods include irradiating the paper product to alter the functionalization of the paper.