The cathode member for electron beam generation of the present disclosure includes: 95% by area or more of a single phase or two phases of a compound composed of iridium and cerium. A total content of one or more subcomponents of metallic iridium and an oxide of one or more elements of iridium and cerium is 5% by area or less of the cathode member.

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).

The present invention is directed to a method for the fabrication of electron field emitter devices, including carbon nanotube (CNT) field emission devices. The method of the present invention involves depositing one or more electrically conductive thin-film layers onto a electrically conductive substrate and performing lithography and etching on these thin film layers to pattern them into the desired shapes. The top-most layer may be of a material type that acts as a catalyst for the growth of single- or multiple-walled carbon nanotubes (CNTs). Subsequently, the substrate is etched to form a high-aspect ratio post or pillar structure onto which the previously patterned thin film layers are positioned. Carbon nanotubes may be grown on the catalyst material layer. The present invention also described methods by which the individual field emission devices may be singulated into individual die from a substrate.

Electron emitters and methods of fabricating the electron emitters are disclosed. According to certain embodiments, an electron emitter includes a tip with a planar region having a diameter in a range of approximately (0.05-10) micrometers. The electron emitter tip is configured to release field emission electrons. The electron emitter further includes a work-function-lowering material coated on the tip.

Template-guided growth of carbon nanotubes using anodized aluminum oxide nanopore templates provides vertically aligned, untangled planarized arrays of multiwall carbon nanotubes with Ohmic back contacts. Growth by catalytic chemical vapor deposition results in multiwall carbon nanotubes with uniform diameters and crystalline quality, but varying lengths. The nanotube lengths can be trimmed to uniform heights above the template surface using ultrasonic cutting, for example. The carbon nanotube site density can be controlled by controlling the catalyst site density. Control of the carbon nanotube site density enables various applications. For example, the highest possible site density is preferred for thermal interface materials, whereas, for field emission, significantly lower site densities are preferable.

There is provided a method for manufacturing a plurality of nanostructures comprising the steps of providing a plurality of spherical Zn structures and oxidizing the spherical structures in ambient atmosphere at a temperature in the range of 350° C. to 600° C. for a time period in the range of h to 172 h, such that ZnO nanowires protruding from the spherical structures are formed. There is also provided a field emission arrangement comprising a cathode having the aforementioned ZnO nanowire structures arranged thereon.

In an embodiment, a method includes forming a first diamond layer on a substrate and inducing a layer of graphene from the first diamond layer by heating the substrate and the first diamond layer. The method includes forming a second diamond layer on top of the layer of graphene and applying a mask to the second diamond layer. The mask includes a shape of a cathode, an anode, and one or more grids. The method further includes forming a two-dimensional cold cathode, a two-dimensional anode, and one or more two-dimensional grids by reactive-ion electron-beam etching. Each of the two-dimensional cold cathode, the two-dimensional anode, and the one or more two-dimensional grids includes a portion of the first diamond layer, the graphene layer, and the second diamond layer such that the graphene layer is positioned between the first diamond layer and the second diamond layer.

A field emission device comprises one or more emitter elements, each having a high aspect ratio structure with a nanometer scaled cross section; and one or more segmented electrodes, each surrounding one of the one or more emitters. Each of the one or more segmented electrodes has multiple electrode plates. This abstract is provided to comply with rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

A nanotip apparatus which includes nanotips arranged in a pattern on a semiconductor base. Each of the nanotips have a pointed tip portion and a base portion in contact with the semiconductor base. Further, each of the nanotips include a gradient of silicon germanium (SiGe) with the highest concentration of germanium being at the pointed tip portion and the lowest concentration of germanium being at the base in contact with the semiconductor base. Also disclosed is a method in which the nanotips may be formed.

Nanoscale field-emission devices are presented, wherein the devices include at least a pair of electrodes separated by a gap through which field emission of electrons from one electrode to the other occurs. The gap is dimensioned such that only a low voltage is required to induce field emission. As a result, the emitted electrons energy that is below the ionization potential of the gas or gasses that reside within the gap. In some embodiments, the gap is small enough that the distance between the electrodes is shorter than the mean-free path of electrons in air at atmospheric pressure. As a result, the field-emission devices do not require a vacuum environment for operation.