A photocathode emitter includes a transparent substrate, a photocathode layer, and a plasmonic structure array disposed between the transparent substrate and the photocathode layer. The plasmonic structure array is configured to operate at a wavelength from 193 nm to 430 nm. The plasmonic structure array can be made of aluminum. An electron beam can be generated from a light beam directed at the plasmonic structure array of the photocathode emitter.

According to one embodiment, an electron-emitting element includes a first member and a second member. The first member includes a semiconductor member of an n-type. The second member includes a diamond member a p-type and includes at least one selected from the group consisting of diamond and graphite. The semiconductor member includes at least one selected from the group consisting of a first material, a second material, and a third material. The first material includes nitrogen and at least one selected from the group consisting of B, Al, In, and Ga. The second material includes at least one selected from the group consisting of ZnO and ZnMgO. The third material includes at least one selected from the group consisting of BaTiO.sub.3, PbTiO.sub.3, Pb(Zr.sub.x, Ti.sub.1-x)O.sub.3, KNbO.sub.3, LiNbO.sub.3, LiTaO.sub.3, Na.sub.xWO.sub.3, Zn.sub.2O.sub.3, Ba.sub.2NaNb.sub.5O.sub.5, Pb.sub.2KNb.sub.5O.sub.15, and Li.sub.2B.sub.4O.sub.7.

Embodiments of the present invention describe electrical potential energy to electrical kinetic energy converters, ozone generators, and light emitters. A system for energy conversion from electrical potential energy to electrical kinetic energy may include a discharge device and a power supply. The power supply can be coupled with the discharge device, and supplies energy to the discharge device to form an initial electric field. The discharge device may further include at least two electrodes that are either mesh electrodes or wire-array electrodes. Furthermore, a space between the at least two electrodes is filled with a gas medium and an electric field is created by the power supply in a normal direction relative to planes formed by the elements of electrodes.

The invention discloses a photocathode comprising an amorphous substrate such as a glass substrate (110) presenting an input face that will receive incident photons and a back face opposite the front face. Nanowires (120) made from at least one III-V semiconducting material are deposited on the back face of the substrate and extend from this face in a direction away from the front face. The invention also relates to a method for manufacturing such a photocathode by MBE.

A photocathode can include a body fabricated of a wide bandgap semiconductor material, a metal layer, and an alkali halide photocathode emitter. The body may have a thickness of less than 100 nm and the alkali halide photocathode may have a thickness less than 10 nm. The photocathode can be illuminated with a dual wavelength scheme.

A photocathode emitter can include a transparent substrate, a photocathode layer, and a plasmonic structure array disposed between the transparent substrate and the photocathode layer. The plasmonic structure can serve as a spot-confining structure and an electrical underlayer for biasing the photocathode. The plasmonic structure can confine the incident light at subwavelength sizes.

A photocathode utilizes an field emitter array (FEA) integrally formed on a silicon substrate to enhance photoelectron emissions, and a thin boron layer disposed directly on the output surface of the FEA to prevent oxidation. The field emitters are formed by protrusions having various shapes (e.g., pyramids or rounded whiskers) disposed in a two-dimensional periodic pattern, and may be configured to operate in a reverse bias mode. An optional gate layer is provided to control emission currents. An optional second boron layer is formed on the illuminated (top) surface, and an optional anti-reflective material layer is formed on the second boron layer. An optional external potential is generated between the opposing illuminated and output surfaces. An optional combination of n-type silicon field emitter and p-i-n photodiode film is formed by a special doping scheme and by applying an external potential. The photocathode forms part of sensor and inspection systems.

A flat top laser beam is used to generate an electron beam with a photocathode that can include an alkali halide. The flat top profile can be generated using an optical array. The laser beam can be split into multiple laser beams or beamlets, each of which can have the flat top profile. A phosphor screen can be imaged to determine space charge effects or electron energy of the electron beam.

A method of manufacturing a multi-layer image intensifier wafer includes fabricating first and second glass wafers, each having an array of cavities that extend between respective openings in first and second surfaces of the respective glass wafer; doping a semiconductor wafer to generate a plurality of electrons for each electron that impinges a first surface of the semiconductor wafer and to direct the plurality of electrons to a second surface of the semiconductor wafer, bonding a photo-cathode wafer to the first glass wafer; bonding the semiconductor wafer between the first and second glass wafers, and bonding the second glass wafer between the semiconductor wafer and an anode wafer (e.g., a phosphor screen or other electron detector). A section of the multi-layer image intensifier wafer may be sliced and evacuated to provide a multi-layer image intensifier.

A photocathode structure, which can include one or more of Cs.sub.2Te, CsKTe, CsI, CsBr, GaAs, GaN, InSb, CsKSb, or a metal, has a protective film on an exterior surface. The protective film includes one or more of ruthenium, nickel, platinum, chromium, copper, gold, silver, aluminum, or an alloy thereof. The protective film can have a thickness from 1 nm to 10 nm. The photocathode structure can be used in an electron beam tool like a scanning electron microscope.