Abstract:
A field-emission electron gun including an electron emission tip, an extractor anode, and a mechanism creating an electric-potential difference between the emission tip and the extractor anode. The emission tip includes a metal tip and an end cone produced by chemical vapor deposition on a nanofilament, the cone being aligned and welded onto the metal tip. The electron gun can be used for a transmission electron microscope.
Abstract:
A tip of an electron beam source includes a core carrying a coating. The coating is formed from a material having a greater electrical conductivity than a material forming the surface of the core.
Abstract:
A method of preparing an ultra sharp tip, in particular a single atom tip, is provided, comprising providing a tip having a shank, an apex, and a coating covering the shank and the apex; locally removing the coating from the apex by field evaporation; and partially or fully restoring the coating at the apex.
Abstract:
A field emission electron source includes a CNT needle and a conductive base. The CNT needle has an end portion and a broken end portion; the end portion is contacted with and electrically connected to a surface of the conductive base. The CNTs at the broken end portion form a taper-shape structure, wherein one CNT protrudes and is higher than the adjacent CNTs.