The present invention provides an emitter, which comprises carbon nanotubes and is excellent in the efficiency of electron emission, and an X-ray tube comprising the same.

A carbon nanotube fiber carpet structure includes a backing material; and a plurality looped carbon nanotube (CNT) fiber conductors fixed to the backing material extending outward from the backing material in an array. The CNT fiber conductor may include at least one of a CNT thread, a CNT fiber, a CNT film, and a CNT ribbon, and the CNT fiber conductor may include a first end and a second end, the first end fixed to the backing material, and the second end fixed to the backing material a predetermined distance from the first end in order to form a loop of the CNT fiber conductor extending away from a backing material surface. The CNT fiber conductor may be woven into the backing material to form a plurality of loops of the CNT fiber conductor extending away from a backing surface material, and the backing material may be a conductive material.

A technique relates to a semiconductor device. An emitter electrode and a collector electrode are formed in a dielectric layer such that a nanogap separates the emitter electrode and the collector electrode, a portion of the emitter electrode including layers. A channel is formed in the dielectric layer so as to traverse the nanogap. A top layer is formed over the channel so as to cover the channel and the nanogap without filling in the channel and the nanogap, thereby forming a vacuum channel transistor structure.

A new ultra-thin high-efficiency photo-electric devices utilizing a plasmonic cavity with subwavelength hole-array (PlaCSH) and various practical devices utilizing such PlaCSH including new light emitting diode (LED), a new photoelectron source, and a new photodetector/solar cell having a photonic resonant cavity with a top metallic layer that is light transmissive, a bottom metallic layer and a middle layer of semiconductor positioned between the top metallic layer and the bottom metallic layer.

A robust cold cathode uses an electron emitting construct design possibly for an x-ray emitter device. The electron beam emitted by the emitting construct is focused and accelerated by an electrical field towards an electron anode target. A shield is provided to prevent a cold cathode from being damaged by ion bombardment in high-voltage applications and a non-emitter zone may provide a robust ion bombardment zone. The system is further configured to provide an angled target anode or a stepped target anode to further reduce the ion bombardment damage.

Controlling total emission current of an electron emitting construct in an x-ray emitting device by providing a cathode, providing multiple active areas each active area having a gated cone electron source, including multiple emitter tips arranged in an array, a gate electrode, and a gate interconnect lead connected to the gate electrode, providing an x-ray emitting construct comprising an anode, the anode being an x-ray target, situating the x-ray emitting construct facing the active areas face each other, selecting a set of active areas, and activating selected active areas by conductively connecting a voltage source to their associated the gate electrode interconnect lead.

Example compact modular electron beam units are provided that can be used to generate electron beams using field emitter elements. A modular electron beam unit may comprise an electron beam source including a base portion, at least one field emitter element coupled to the base portion, the field emitter element including a field emitter tip, at least one gate electrode and a membrane window disposed over the at least one gate electrode.

An electron emitting construct design of an x-ray emitter device is disclosed configured to facilitate radiation in the X-ray spectrum and further relates to preventing a cold cathode from being damaged by ion bombardment in high-voltage applications. The electron beam emitted by the emitting construct is focused and accelerated by an electrical field towards an electron anode target operable to attract electron beam to an associated focal spot, wherein the generated ions are accelerated along a trajectory perpendicular to the electric field in parallel to the surface of the electron anode target. More specifically, the present invention relates to realizing a robust cold cathode to avoid ion bombardments damages in high-voltage applications, by means of setting non-emitter zone surrounded by or set between the emitter areas. The system is further configured to provide an angled target anode or a stepped target anode to further reduce the ion bombardment damage.

The disclosure relates to an image capture device comprising an electron receiving construct and an electron emitting construct, and further comprising an inner gap providing an unobstructed space between the electron emitting construct and the electron receiving construct. The disclosure further relates to an x-ray emitting device comprising an x-ray emitting construct and an electron emitting construct, said x-ray emitting construct comprising an anode, the anode being an x-ray target, wherein the x-ray emitting device may comprise an inner gap providing an unobstructed space between the electron emitting construct and the x-ray emitting construct. The disclosure further relates to an x-ray imaging system comprising an image capture device and an x-ray emitting device.

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.