An electron emission structure according to embodiments of the inventive concept includes a cathode electrode and electron emission yarns each having a yarn shape and disposed in the cathode electrode. Here, the cathode electrode includes a plurality of first conductive panels spaced apart from each other in a first direction and at least one second conductive panel that crosses the first conductive panels in the first direction. Also, each of the first conductive panels includes at least one groove at an upper portion thereof. The second conductive panel is inserted to the groove of each of the first conductive panels. Each of the electron emission yarns is disposed between the first conductive panels. Each of the electron emission yarns contacts the second conductive panel. Each of the electron emission yarns is mechanically fixed and vertically aligned as well as arranged regularly by the second conductive panel and one pair of adjacent first conductive panels of the first conductive panels.

An X-ray tube according to an embodiment of the inventive concept includes a cathode structure; an anode structure spaced vertically from the cathode structure, a gate electrode structure disposed between the cathode structure and the anode structure, an emitter array disposed between the cathode structure and the gate electrode structure, a tube sheath configured to connect the cathode structure and the anode structure, and a fixing unit connected with the gate electrode structure. The cathode structure includes a first rotation shaft and a cathode connected with the first rotation shaft as one body. The gate electrode structure includes a second rotation shaft and a gate electrode connected with the second rotation shaft through a bearing, and the second rotation shaft is connected with the first rotation shaft by a coupling unit. The gate electrode includes a gate electrode substrate and a protruding part that protrudes from the gate electrode substrate toward an emitter. The protruding part of the gate electrode includes a gate hole that vertically overlaps the emitter. The fixing unit includes a ferromagnetic structure attached to one surface of the gate electrode substrate and disposed on an outer portion of the substrate and a permanent magnet disposed adjacent to the ferromagnetic structure with the tube sheath therebetween.

Methods and systems for realizing a high radiance x-ray source based on a high density electron emitter array are presented herein. The high radiance x-ray source is suitable for high throughput x-ray metrology and inspection in a semiconductor fabrication environment. The high radiance X-ray source includes an array of electron emitters that generate a large electron current focused over a small anode area to generate high radiance X-ray illumination light. In some embodiments, electron current density across the surface of the electron emitter array is at least 0.01 Amperes/mm.sup.2, the electron current is focused onto an anode area with a dimension of maximum extent less than 100 micrometers, and the spacing between emitters is less than 5 micrometers. In another aspect, emitted electrons are accelerated from the array to the anode with a landing energy less than four times the energy of a desired X-ray emission line.

A MBFEX tube (1) for an x-ray device comprises, in a vacuum tube (20), an anode (30) designed as a cooling finger and securely arranged in the vacuum tube, and a plurality of securely arranged cathodes (40, 41, 42), wherein the vacuum tube (20) comprises a plurality of cathode feed lines (50) and no more than two high-voltage bushings (51, 52), in a high-voltage bushing (52) a coolant pipe (31) is passed through by an internal coolant inner pipe (32), the coolant pipe (31) and the coolant inner pipe (32) are provided for cooling the anode (30) with a liquid coolant, the cathodes (40, 41, 42) are provided for field emission of electrons and are arranged on the anode (30) for generating x-ray sources (Q).

The present disclosure relates to a CNT X-ray source apparatus, and more particularly, to a CNT X-ray source apparatus configured to maximize utilization of the internal space of a CNT X-ray tube body, having grooves made of an insulating material, and provided with a base portion for supporting a plurality of electrodes. With this configuration, mass production is possible. The CNT X-ray source apparatus of the present disclosure includes a cathode electrode; an emitter provided on the cathode electrode and responsible for emitting electrons; a gate electrode disposed above the cathode electrode and spaced apart from the cathode electrode by a predetermined interval; a focusing electrode for preventing scattering of electrons emitted from the emitter; and a base portion responsible for supporting one or more of the cathode electrode, the gate electrode, and the focusing electrode and formed of an insulating material. In this case, one or more grooves for accommodating at least one of the cathode electrode, the gate electrode, and the focusing electrode are formed in the base portion.

Some embodiments include an x-ray source, comprising: an anode; a field emitter configured to generate an electron beam; a first grid configured to control field emission from the field emitter; a second grid disposed between the first grid and the anode; and a middle electrode disposed between the first grid and the anode wherein the second grid is either disposed between the first grid and middle electrode or between the middle electrode and the anode.

An X-ray tube according to an embodiment of the inventive concept includes a cathode structure; an anode structure spaced vertically from the cathode structure, a gate electrode structure disposed between the cathode structure and the anode structure, an emitter array disposed between the cathode structure and the gate electrode structure, a tube sheath configured to connect the cathode structure and the anode structure, and a fixing unit connected with the gate electrode structure. The cathode structure includes a first rotation shaft and a cathode connected with the first rotation shaft as one body. The gate electrode structure includes a second rotation shaft and a gate electrode connected with the second rotation shaft through a bearing, and the second rotation shaft is connected with the first rotation shaft by a coupling unit. The gate electrode includes a gate electrode substrate and a protruding part that protrudes from the gate electrode substrate toward an emitter. The protruding part of the gate electrode includes a gate hole that vertically overlaps the emitter. The fixing unit includes a ferromagnetic structure attached to one surface of the gate electrode substrate and disposed on an outer portion of the substrate and a permanent magnet disposed adjacent to the ferromagnetic structure with the tube sheath therebetween.

Some embodiments include an x-ray source, comprising: an anode; a field emitter configured to generate an electron beam; a first grid configured to control field emission from the field emitter; a second grid disposed between the first grid and the anode; a third grid disposed between the first grid and the anode; and a middle electrode disposed between the first grid and the anode wherein the second grid is either disposed between the first grid and middle electrode or between the middle electrode and the anode; wherein the third grid is a mesh grid.

A field emission cathode device comprises a field emission cathode including a cylindrical substrate and a field emission material deposited on a cylindrical surface thereof. The field emission cathode defines a longitudinal axis. A solenoid extends concentrically about the cylindrical surface, and defines a gap therebetween. The solenoid defines opposed open ends perpendicular to the longitudinal axis. A current source directs a constant polarity (DC) current to the solenoid, that forms a magnetic field along the solenoid. A gate voltage source electrically connected to the solenoid or the field emission cathode interacts therewith to generate an electric field inducing the field emission cathode to emit electrons from the field emission material into the gap. The emitted electrons are responsive to the magnetic field to spiral within the gap and about the longitudinal axis, in correspondence with the current flow in the solenoid, through the first open end of the solenoid.

An X-ray radiator and an X-ray assembly are disclosed. The X-ray radiator according to an embodiment has an evacuated X-ray tube housing, mounted to be rotatable about a rotation axis, the X-ray tube housing including an anode and an electron source. The anode is arranged within the X-ray tube housing non-rotatably relative to the X-ray tube housing and is configured to generate X-ray radiation via electrons impacting upon a focal spot of the anode, the electron source being mounted substantially stationary within the X-ray tube housing relative to the rotation axis. The electron source has a main emitter and at least one subsidiary emitter for emitting electrons. The electron emission of the main emitter and/or of the at least one subsidiary emitter is controllable such that a spatial movement of the focal spot due to a movement of the electron source is reduced.