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.

The electron gun is provided with a first anode electrode and a second anode electrode to generate an acceleration and deceleration electric field. A lens electric field makes it possible to irradiate a sample with an electron beam emitted from a part outside an optical axis of the photoelectric film without being blocked by a differential exhaust diaphragm. A wide range of electron beams off-optical axis can be used even in a high-brightness photocathode that requires high vacuum. As a result, the photoelectric film and the electron gun can be extended in life, can be stabilized, and can be increased in brightness. Further, it is possible to facilitate a control of emitting electron beams from a plurality of positions on the photoelectric film, a timing control of emitting electron beams from a plurality of positions, a condition control of an electron beam in an electron microscope using electron beams.

A pulsed generator of electrically charged particles includes a vacuum chamber; wherein the vacuum chamber is configured to maintain an internal operating pressure between 10-6 mbar and atmospheric pressure; the vacuum chamber is configured to accommodate a photocathode and an anode, the photocathode and the anode being separated by an adjustable distance less than or equal to 30 mm; the vacuum chamber includes a window enabling pulsed light to reach firstly a rear face of the photocathode; the anode is arranged downstream of the photocathode and has an orifice suitable for the passage of electrically charged particles; the generator of electrically charged particles includes a system to apply a difference in potential between the photocathode and the anode, the voltage being configured to accelerate the charged particles.

The present invention relates to a monochromator device. The monochromator device includes a first radiofrequency cavity positioned to receive an output beam from an electron source. A second radiofrequency cavity is positioned to receive the output beam from the first radiofrequency cavity. The first radiofrequency cavity and the second radiofrequency cavity are configured to, in combination, in combination, correct one or more energy deviations in time and space of the output beam.

An object is to provide an electron gun that makes it possible to verify whether or not an electron beam emitted form a photocathode is misaligned from a designed emission center axis. The object can be achieved by an electron gun including: a light source; a photocathode; and an anode. The electron gun includes an intermediate electrode arranged between the photocathode and the anode, an electron beam shielding member configured to block a part of an electron beam, a measurement unit configured to measure an intensity of an electron beam blocked by the electron beam shielding member, and an electron beam emission direction deflector arranged between the anode and the electron beam shielding member and configured to change a position where an electron beam that passed through the anode reaches the electron beam shielding member. The intermediate electrode has an electron beam passage hole and a drift space.

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 dielectric coated plasmonic photoemitter is provided. An aspect of the present photonic apparatus includes a conductive photoemitter including a dielectric material coating or layered on a metallic core. The dielectric material being configured to enhance a local optical field strength and current density of the photoemitter as compared to a bare photoemitter without the dielectric layer. The dielectric layered photoemitter being tunable to transmit photoemissions from corners thereof with different photonic characteristics depending on a laser wavelength pulse received.

The present disclosure addresses the problem of providing an electron gun that can directly monitor an intensity of an electron beam emitted from a photocathode using only the configuration provided to the electron gun, an electron beam applicator equipped with an electron gun, and a method for controlling an electron gun.

The aforementioned problem can be solved by an electron gun comprising a light source, a photocathode that emits an electron beam in response to receiving light from the light source, an anode, an electron-beam-shielding member with which it is possible to shield part of the electron beam, and a measurement unit that measures the intensity of the electron beam emitted from the photocathode using a measurement electron beam shielded by the electron-beam-shielding member.

According to one aspect of the present invention, an electron beam irradiation apparatus includes a photoelectric surface configured to receive irradiation of excitation light on a side of a front surface, and generate electron beams from a side of a back surface; a blanking aperture array mechanism provided with passage holes corresponding to the electron beams and configured to perform deflection control on each of the plurality of electron beams passing through the passage holes; and an adjustment mechanism configured to adjust at least one of an orbit of transmitted light that passes through at least one of arrangement objects including the photoelectric surface, the blanking aperture array mechanism, and the limit aperture substrate up to the stage and reaches the stage, among an irradiated excitation light, and an orbit of the electron beams, wherein the arrangement objects shield at least a part of the transmitted light.