Systems and methods are described herein for electron-beam lithography. In some aspects, a photo electron emitter and channel array assembly (PEECAA) may include a photo-electron emitting cathode having a uniform planar surface and an array of beam channels proximate to the cathode. In some cases, at least one of the cathode or the array of beam channels is removable from the PEECAA. The array of beam channels may include a grid of apertures, a plurality of beam channels, and a shared lens array including a plurality of lenses proximate to an exit of the plurality of beam channels. Individual apertures of the grid of apertures align with individual beam channels to allow electrons from the cathode to pass through the array of beam channels and the shared lens array to form a pixelated pattern, such that, upon exposure to the target, the pixelated pattern is permanently formed on the target.

A system for generating an electron beam array, comprising a light source, a first substrate having a plurality of plasmonic lenses mounted thereon, the plasmonic lenses configured to received light from the light source and produce an electron emission, and a plurality of electrostatic microlenses configured to focus the electron emissions into a beam for focusing on a wafer substrate. A light source modulator and digital micro mirror may be included which captures light from the light source and projects light beamlets on the plasmonic lenses.

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.

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.

To provide an electron microscope capable of performing the switching-over between normal illumination and annular illumination, wide-area irradiation, an interference pattern as desired or normal illumination in an expeditious and readily manner or achieving a better S/N ratio, the electron microscope comprises a photocathode 101 with negative electron affinity in use; an excitation optical system to excite the photocathode; and an electron optics system to irradiate an electron beam 13 generated from the photocathode by excitation light 12 irradiated through the excitation optical system onto a sample, the excitation optical system including a light source device 107 for the excitation light; and an optical modulation means 108 which is disposed in an optical path of the excitation light to perform spatial phase modulation to the excitation light.

The system includes a photocathode electron source, diffractive optical element, and a microlens array to focus the beamlets. A source directs a radiation beam to the diffractive optical element, which produces a beamlet array to be used in combination with a photocathode surface to generate an array of electron beams from the beamlets.

An interferometric electron microscope with increased irradiating electric current density which causes electron waves to interfere with each other and includes: an electron source; an irradiating lens system a focusing lens system an observational plane an artificial grating disposed between the electron source and the irradiating lens system and diffracting the electron beam emitted from the electron source to produce a first electron wave and a second electron wave; an electron beam biprism deflecting the first electron wave and the second electron wave to pass the first electron wave through the specimen for use as an object wave and to use the second electron wave as a reference wave; and an electron beam biprism in a focusing system deflecting the objective wave and the reference wave to superimpose the objective wave and the reference wave on the observational plane to produce an image.

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 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.

An electron beam source is provided that includes a vessel forming a chamber, a cathode disposed within the chamber, the cathode comprising a low dimensional electrically conductive material having an anisotropic restricted thermal conductivity, an electrode disposed in the chamber, the electrode being connectable to a power source for applying a positive voltage to the electrode relative to the cathode for accelerating free electrons away from the cathode to form an electron beam when the cathode is illuminated by electromagnetic (EM) radiation such that the cathode thermionically emits free electrons, and an electron emission window in the chamber for passing a generated electron beam out of the chamber. An electron microscope that incorporates the electron beam source is also provided.