The invention provides an electron source including a columnar chip of a hexaboride single crystal, a metal pipe that holds the columnar chip of the hexaboride single crystal, and a filament connected to the metal pipe at a central portion. The columnar chip of the hexaboride single crystal is formed into a cone shape at a portion closer to a tip than a portion held in the metal pipe, and a tip end portion having the cone shape has a (310) crystal face. Schottky electrons are emitted from the (310) crystal face. According to the invention, it is possible to provide a novel electron source having monochromaticity, long-term stability of an emitter current, and high current density.

An electron beam system for wafer inspection and review of 3D devices provides a depth of focus up to 20 microns. To inspect and review wafer surfaces or sub-micron-below surface defects with low landing energies in hundreds to thousands of electron Volts, a Wien-filter-free beam splitting optics with three magnetic deflectors can be used with an energy-boosting upper Wehnelt electrode to reduce spherical and chromatic aberration coefficients of the objective lens.

An electron beam system for wafer inspection and review of 3D devices provides a depth of focus up to 20 microns. To inspect and review wafer surfaces or sub-micron-below surface defects with low landing energies in hundreds to thousands of electron Volts, a Wien-filter-free beam splitting optics with three magnetic deflectors can be used with an energy-boosting upper Wehnelt electrode to reduce spherical and chromatic aberration coefficients of the objective lens.

This invention provides a charged particle source, which comprises an emitter and means for generating a magnetic field distribution. The magnetic field distribution is minimum, about zero, or preferred zero at the tip of the emitter, and along the optical axis is maximum away from the tip immediately. In a preferred embodiment, the magnetic field distribution is provided by dual magnetic lens which provides an anti-symmetric magnetic field at the tip, such that magnetic field at the tip is zero.

This invention provides a charged particle source, which comprises an emitter and means for generating a magnetic field distribution. The magnetic field distribution is minimum, about zero, or preferred zero at the tip of the emitter, and along the optical axis is maximum away from the tip immediately. In a preferred embodiment, the magnetic field distribution is provided by dual magnetic lens which provides an anti-symmetric magnetic field at the tip, such that magnetic field at the tip is zero.

A charged particle beam source, such as for use in an electron microscope, can include an electrically conductive support member coupled to a base, a mounting member coupled to the support member and defining a bore, and an emitter member received in the bore and retained by a fixative material layer flowed around the emitter member in the bore.

A charged particle beam source that may include an emitter that has a tip for emitting charged particles; a socket; electrodes; a filament that is connected to the electrodes and to the emitter; electrodes for providing electrical signals to the filament; a support element that is connected to the emitter; and a support structure that comprises one or more interfaces for contacting only a part of the support element while supporting the support element.

A magnetically microfocused electron emission source apparatus is disclosed. The apparatus may include a magnetic emitter unit, wherein the magnetic emitter unit comprises an emitter. Further, the magnetic emitter unit may include one or more magnetic portions formed from one or more magnetic materials, wherein the one or more magnetic portions of the magnetic emitter unit are configured to generate a magnetic field proximate to a tip of the emitter of the magnetic emitter unit for enhancing focusing of the emitted electrons from the electron emitter.

An electron beam (EB) gun assembly for an EB furnace is provided. The EB gun assembly includes an EB gun-frame assembly including a skeleton frame and at least one EB gun mounted to the skeleton frame, and the EB gun-frame assembly is configured to rigidly mount onto a first EB chamber lid and melt material in a first EB chamber and be removed and rigidly mount onto a second EB chamber lid and melt material in a second EB chamber. In some forms, the EB gun assembly includes at least one mounting frame and the at least one EB gun is mounted to the at least one mounting frame and the at least one mounting frame is mounted to the skeleton frame.

Various embodiments of the present technology generally relate to devices and methods for generating and directing energetic electrons toward a target. More specifically, some embodiments relate to devices, systems, and methods for generating and directing energetic electrons based in the photoelectric effect and directing electric field-focused beams of the energetic electrons toward a target. Electron guns according to the present technology include one or more light sources to stimulate electron transmission, and a series of differentially charged stages to provide a hollow path allowing electrons generated by the photoelectric effect of the light irradiated on interior surfaces defining the path through the stages to travel to an exit of the electron gun. Each of the differentially charged stages have a different potential, thereby providing electrons having two or more different and tunable energy levels exiting as a beam from the electron gun.