The present invention relates to large area field emission devices based on the incorporation of macroscopic, microscopic, and nanoscopic field enhancement features and a designed forced current sharing matrix layer to enable a stable high-current density long-life field emission device. The present invention pertains to a wide range of field emission sources and is not limited to a specific field emission technology. The invention is described as an X-ray electron source but can be applied to any application requiring a high current density electron source.

A CNT X-ray tube control system according to an embodiment of the present disclosure includes a CNT X-ray tube including an anode electrode, a gate electrode, and a cathode electrode, and configured to generate X-rays from electric field emission; a dummy load including an anode electrode, a gate electrode, and a cathode electrode, and configured not to generate X-rays, the dummy load being connected to the CNT X-ray tube in parallel; a high-voltage part configured to control a voltage applied to the CNT X-ray tube; and a controller configured to control the CNT X-ray tube, the dummy load, and the high-voltage part. Particularly, a portable X-ray generation apparatus reduced in size can be provided, the apparatus including the dummy load having the same structure as a CNT to minimize the voltage variation of the high-voltage part during the ON/OFF operation of the CNT.

A method for imaging one dimension nanomaterials is provided. Firstly, one dimension nanomaterials sample, an optical microscope with a liquid immersion objective and a liquid are provided. Secondly, the one dimensional nanomaterials sample is immersed in the liquid. Thirdly, the one dimensional nanomaterials sample is illuminated by an incident beam to generate resonance Rayleigh scattering. Forthly, the liquid immersion objective is immersed into the liquid to get a resonance Rayleigh scattering (RRS) image of the one dimensional nanomaterials sample. Fifthly, spectra of the one dimensional nanomaterials sample are measured to obtain chirality of the one dimensional nanomaterials sample.

An alternating stack of layers of a first epitaxial semiconductor material and a second epitaxial semiconductor material is formed on a substrate. A fin stack is formed by patterning the alternating stack into a shape of a fin having a parallel pair of vertical sidewalls. After formation of a disposable gate structure and an optional gate spacer, raised active regions can be formed on end portions of the fin stack. A planarization dielectric layer is formed, and the disposable gate structure is subsequently removed to form a gate cavity. A crystallographic etch is performed on the first epitaxial semiconductor material to form vertically separated pairs of an upright triangular semiconductor nanowire and an inverted triangular semiconductor nanowire. Portions of the epitaxial disposable material are subsequently removed. After an optional anneal, the gate cavity is filled with a gate dielectric and a gate electrode to form a field effect transistor.

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 method for assigning chirality of carbon nanotube is provided. Firstly, carbon nanotube sample, an optical microscope with a liquid immersion objective and a liquid are provided. Secondly, the carbon nanotube sample is immersed in the liquid. Thirdly, the carbon nanotube sample is illuminated by an incident beam to generate resonance Rayleigh scattering. Forthly, the liquid immersion objective is immersed into the liquid to get a resonance Rayleigh scattering (RRS) image of the carbon nanotube sample. Fifthly, spectra of the carbon nanotube sample are measured to obtain chirality of the carbon nanotube sample.

Disclosed is a field emission-type tomosynthesis system including a vacuum body having a space therein; a plurality of sources provided inside the body, wherein each of the sources emits a plurality of electrons; and a plurality of anodes disposed inside the body to face the sources and responsible for emitting a plurality of X-rays, wherein each of the anodes faces a corresponding source among the sources, and the electrons collide with each of the anodes to generate X-rays, wherein the X-ray emission angle of each of the anodes is capable of being independently adjusted so as to focus the X-rays emitted toward an object located outside the body. With this configuration, a plurality of X-rays is focused on an object and is emitted to the object to obtain information, and the information is synthesized, thereby improving the reliability of information about the object.

A method for manufacturing a carbon nanotube (CNT) of a predetermined length is disclosed. The method includes generating an electric field to align one or more CNTs and severing the one or more aligned CNTs at a predetermined location. The severing each of the aligned CNTs may include etching the predetermined location of the one or more aligned CNTs and applying a voltage across the one or more etched CNTs.

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.

Disclosed is an X-ray source, including: a cathode including a shielding channel through which an X-ray passes; emitters formed on an upper surface of the cathode, and arranged around the shielding channel; an anode positioned so as to face the cathode, and including an anode target in which an E-beam is focused; and a gate electrode positioned between the cathode and the anode, and including gate holes at positions corresponding to those of the emitters.