A charged particle source is provided that exhibits small energy dispersion for charged particle beams emitted under a high angular current density condition and allows stable acquisition of large charged particle currents even for a small light source diameter. The charged particle source has a spherical virtual cathode surface from which charged particles are emitted, and the virtual cathode surface for charged particles emitted from a first position on a tip end surface of an emitter and the virtual cathode surface for charged particles emitted from a second position on the tip end surface of the emitter match each other.

A charged particle source is provided that exhibits small energy dispersion for charged particle beams emitted under a high angular current density condition and allows stable acquisition of large charged particle currents even for a small light source diameter. The charged particle source has a spherical virtual cathode surface from which charged particles are emitted, and the virtual cathode surface for charged particles emitted from a first position on a tip end surface of an emitter and the virtual cathode surface for charged particles emitted from a second position on the tip end surface of the emitter match each other.

The invention relates to an electron source comprising a conductive substrate, a conductor disposed facing the substrate, the electron source emitting an electron beam when the conductor is positively biased with respect to the substrate, and an electrically insulating crystal arranged on the substrate, facing the conductor, the substrate defining with the crystal a void including at least one peak located at a distance from the crystal, the crystal having, in a plane parallel to the substrate, dimensions of less than 100 nm and a thickness of less than 50 nm.

The invention relates to an electron source comprising a conductive substrate, a conductor disposed facing the substrate, the electron source emitting an electron beam when the conductor is positively biased with respect to the substrate, and an electrically insulating crystal arranged on the substrate, facing the conductor, the substrate defining with the crystal a void including at least one peak located at a distance from the crystal, the crystal having, in a plane parallel to the substrate, dimensions of less than 100 nm and a thickness of less than 50 nm.

A light modulated electron source utilizes a photon-beam source to modulate the emission current of an electron beam emitted from a silicon-based field emitter. The field emitter's cathode includes a protrusion fabricated on a silicon substrate and having an emission tip covered by a coating layer. An extractor generates an electric field that attracts free electrons toward the emission tip for emission as part of the electron beam. The photon-beam source generates a photon beam including photons having an energy greater than the bandgap of silicon, and includes optics that direct the photon beam onto the emission tip, whereby each absorbed photon creates a photo-electron that combines with the free electrons to enhance the electron beam's emission current. A controller modulates the emission current by controlling the intensity of the photon beam applied to the emission tip. A monitor measures the electron beam and provides feedback to the controller.

A light modulated electron source utilizes a photon-beam source to modulate the emission current of an electron beam emitted from a silicon-based field emitter. The field emitter's cathode includes a protrusion fabricated on a silicon substrate and having an emission tip covered by a coating layer. An extractor generates an electric field that attracts free electrons toward the emission tip for emission as part of the electron beam. The photon-beam source generates a photon beam including photons having an energy greater than the bandgap of silicon, and includes optics that direct the photon beam onto the emission tip, whereby each absorbed photon creates a photo-electron that combines with the free electrons to enhance the electron beam's emission current. A controller modulates the emission current by controlling the intensity of the photon beam applied to the emission tip. A monitor measures the electron beam and provides feedback to the controller.

Apparatuses, methods, and systems for ultra-fast beam current adjustment for a charged-particle inspection system include an charged-particle source configured to emit charged particles for scanning a sample; and an emission booster configured to configured to irradiate electromagnetic radiation onto the charged-particle source for boosting charged-particle emission in a first cycle of a scanning operation of the charged-particle inspection system, and to stop irradiating the electromagnetic radiation in a second cycle of the scanning operation.

Apparatuses, methods, and systems for ultra-fast beam current adjustment for a charged-particle inspection system include an charged-particle source configured to emit charged particles for scanning a sample; and an emission booster configured to configured to irradiate electromagnetic radiation onto the charged-particle source for boosting charged-particle emission in a first cycle of a scanning operation of the charged-particle inspection system, and to stop irradiating the electromagnetic radiation in a second cycle of the scanning operation.

An object is to provide an electron gun that can extend the lifetime of a photocathode. The object can be achieved by an electron gun including: a substrate having a photocathode film formed on a first face; a light source for irradiating the photocathode film with excitation light; an anode; a heater device for heating the photocathode film and/or the substrate; and an output adjustment device that adjusts a heating temperature of the heater device.

An object is to provide an electron gun that can extend the lifetime of a photocathode. The object can be achieved by an electron gun including: a substrate having a photocathode film formed on a first face; a light source for irradiating the photocathode film with excitation light; an anode; a heater device for heating the photocathode film and/or the substrate; and an output adjustment device that adjusts a heating temperature of the heater device.