Provided is a method for manufacturing an electric field emission device. The method for manufacturing the electric field emission device includes winding a carbon nanotube yarn around outer circumferential surfaces of a metal plate in a first direction, pressing both side surfaces of the metal plate through a pair of metal structures, wherein a top surface of the metal plate is exposed from the metal structures, and an area of the top surface of the metal plate is less than that of each of both the side surfaces of the metal plate, and cutting the carbon nanotube yarn at an edge portion of the top surface of the metal plate in the first direction to form a plurality of emitters.

A method of preparing tunable inorganic patterned nanofeatures by infiltration of a block copolymer scaffold having a plurality of self-assembled periodic polymer microdomains. The method may be used sequential infiltration synthesis (SIS), related to atomic layer deposition (ALD). The method includes selecting a metal precursor that is configured to selectively react with the copolymer unit defining the microdomain but is substantially non-reactive with another polymer unit of the copolymer. A tunable inorganic features is selectively formed on the microdomain to form a hybrid organic/inorganic composite material of the metal precursor and a co-reactant. The organic component may be optionally removed to obtain an inorganic feature s with patterned nanostructures defined by the configuration of the microdomain.

The purpose of the present invention is to provide an emitter that is made of hafnium carbide (HfC) and that releases electrons in a stable and highly efficient manner, a method for manufacturing the emitter, and an electron gun and electronic device in which the emitter is used. In this nanowire equipped emitter, the nanowires are made of hafnium carbide (HfC) single crystal, the longitudinal direction of the nanowires match the <100> crystal direction of the hafnium carbide single crystal, and the end part of the nanowires through which electrons are to be released comprise the (200) face and the {310} face of the hafnium carbide single crystal, with the (200) face being the center and the {311} faces surrounding the (200) face.

An electron source has an insulating base, a pair of conductive terminals, an insulating support member, a drift isolation member, an emitter-cathode, and one or more heating elements. The conductive terminals are exposed from a first surface of the insulating base. The insulating support member extends from the first surface of the insulating base. The drift isolation member is disposed at an end of the insulating support member remote from the insulating base. The emitter-cathode is coupled to the drift isolation member. The one or more heating elements are coupled to the conductive terminals and the drift isolation member. The combination of the drift isolation member with the insulating support member can prevent stress-induced drift from impacting position of the emitter-cathode, thereby improving the mechanical stability of the electron source.

An electron emission source is provided. The electron emission source includes a first electrode, an insulating layer, and a second electrode. The first electrode, the insulating layer, and the second electrode are successively stacked with each other. the second electrode is a graphene layer, and the graphene layer is an electron emission end to emit electron. A thickness of the graphene layer ranges from about 0.1 nanometers to about 50 nanometers.

A method for making field emission devices so that they have emitter tips in the form of a needle-like point with a width and length configured such that ratio of the width to the length ranges from about 0.001 to about 0.05, and associated methods for making the tips by 3-D printing.

A cathode structure for cold field electron emission and method of fabricating a single-tip cathode structure for cold field electron emission. The cathode structure comprises a pointed cathode wire; and a graphene-based coating on at least a tip of the pointed cathode wire. In a preferred embodiment, graphene is coated on nickel tips by chemical vapour deposition wherein nickel functions as a catalyst for growth of graphene. The cathode structure provides stable cold field emission for electron microscopy and lithography applications and exhibits an ultralow work function value of about 1.1 eV.

The purpose of the present invention is to provide a charged particle source that exhibits small energy dispersion for charged particle beams emitted under a high angular current density condition and allows stable acquisition of large charged particle currents even for a small light source diameter. The charged particle source according to the present invention has a spherical virtual cathode surface from which charged particles are emitted, and the virtual cathode surface for charged particles emitted from a first position on a tip end surface of an emitter and the virtual cathode surface for charged particles emitted from a second position on the tip end surface of the emitter match each other (see FIG. 4).

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.

An electron emission source is provided. The electron emission source comprises a first electrode, an insulating layer, and a second electrode, The first electrode, the insulating layer, and the second electrode are successively stacked with each other. the second electrode is a graphene layer, and the graphene layer is an electron emission end to emit electron. A thickness of the graphene layer ranges from about 0.1 nanometers to about 50 nanometers.