Adjustable resolution electron energy loss spectroscopy methods and apparatus are disclosed herein. An example method includes operating an electron microscope in a first state, the first state including operating a source of the electron microscope at a first temperature, obtaining, by the electron microscope, a first EELS spectrum of a sample at a first resolution, the first resolution based on the first temperature, operating the electron microscope in a second state, the second state including operating the source of the electron microscope at a second temperature, the second temperature different than the first temperature, and obtaining, by the electron microscope, a second EELS spectrum of the sample at a second resolution, the second resolution based on the second temperature, wherein the second resolution is different than the first resolution.

The present invention is to provide an electron microscope capable of being activated to an appropriate temperature by disposing an NEG at an extraction electrode around an electron source. The present invention is an electron microscope provided with an electron gun, in which the electron gun includes an electron source, an extraction electrode, and an accelerating tube, the accelerating tube is connected to the extraction electrode at a connection portion, the extraction electrode includes a first heater and a first NEG, and the first heater and the first NEG are spaced apart in an axial direction of an electron beam emitted from the electron source.

An emitter includes an insulator, a pair of terminals attached to the insulator separately from each other, at least one filament attached between the pair of terminals in an arch shape, and an electron source fixed to the filament. The filament has bent portions between a contact with respect to the electron source and contacts with respect to the terminals. A device is provided with the emitter.

An extraction set including an extraction plate, a blocker and the holding mechanism for the blocker is disclosed. The extraction set includes an extraction plate that may be constructed of titanium coated with a ceramic material. The extraction plate is attached to the ion source using pins. The extraction plate also includes raised outline in its inner surface which is used to secure the blocker to the inner surface of the extraction plate. The ends of the blocker are secured by two holders disposed on opposite sides of the extraction aperture. The mechanism used for attaching the extraction plate to the ion source also improves the temperature uniformity of the extraction plate.

An ElectroMagnetic-Mechanical Pulser (EMMP) generates electron pulses at a continuously tunable rate between 100 MHz and 20-50 GHz, with energies up to 0.5 MeV, duty cycles up to 20%, and pulse widths between 100 fs and 10 ps. A dielectric-filled Traveling Wave Transmission Stripline (TWTS) that is terminated by an impedance-matching load such as a 50 ohm load imposes a transverse modulation on a continuous electron beam. The dielectric is configured such that the phase velocity of RF propagated through the TWTS matches a desired electron energy, which can be between 100 and 500 keV, thereby transferring electromagnetic energy to the electrons. The beam is then chopped into pulses by an adjustable aperture. Pulse dispersion arising from the modulation is minimized by a suppressing section that includes a mirror demodulating TWTS, so that the spatial and temporal coherence of the pulses is substantially identical to the input beam.

A method for detecting electron beam filament wear in an electron beam source, the method comprising the steps of: enlarging a beam spot emanating from the electron beam source on a work table to a predetermined minimum size, capturing an image of the beam spot on the work table by a camera, comparing the captured image of the beam spot with a reference image, and detecting filament wear if the captured image is deviating more than a predetermined value from the reference image.

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.

Provided herein are approaches for dynamically modifying plasma volume in an ion source chamber by positioning an end plate and radio frequency (RF) antenna at a selected axial location. In one approach, an ion source includes a plasma chamber having a longitudinal axis extending between a first end wall and a second end wall, and an RF antenna adjacent a plasma within the plasma chamber, wherein the RF antenna is configured to provide RF energy to the plasma. The ion source may further include an end plate disposed within the plasma chamber, adjacent the first end wall, the end plate actuated along the longitudinal axis between a first position and a second position to adjust a volume of the plasma. By providing an actuable end plate and RF antenna, plasma characteristics may be dynamically controlled to affect ion source characteristics, such as composition of ion species, including metastable neutrals.

A magnetic gun lens and an electrostatic gun lens can be used in an electron beam apparatus and can help provide high resolutions for all usable electron beam currents in scanning electron microscope, review, and/or inspection uses. An extracted beam can be directed at a wafer through a beam limiting aperture using the magnetic gun lens. The electron beam also can pass through an electrostatic gun lens after the electron beam passes through the beam limiting aperture.

An emitter includes an insulator, a pair of terminals attached to the insulator separately from each other, at least one filament attached between the pair of terminals in an arch shape, and an electron source fixed to the filament. The filament has bent portions between a contact with respect to the electron source and contacts with respect to the terminals. A device is provided with the emitter.