An X-ray source (10) for emitting an X-ray beam (101) is proposed. The X-ray source (10) comprises an anode (12) and an emitter arrangement (14) comprising a cathode (16) for emitting an electron beam (15) towards the anode (12) and an electron optics (18) for focusing the electron beam (15) at a focal spot (20) on the anode (12). The X-ray source (10) further comprises a controller (22) configured to determine a switching action of the emitter arrangement (14) and to actuate the emitter arrangement (14) to perform the switching action, the switching action being associated with a change of at least one of a position of the focal spot (20) on the anode (12), a size of the focal spot (20), and a shape of the focal spot (20). The controller (22) is further configured to predict before the switching action is performed, based on the determined switching action, the size and the shape of the focal spot (20) expected after the switching action. Further, the controller (22) is configured to actuate the electron optics (18) to compensate for a change of the size and the shape of the focal spot (20) induced by the switching action.

A source for generating ionizing radiation and in particular x-rays, to an assembly includes a plurality of sources and to a process for producing the source. The source comprises: a vacuum chamber; a cathode that is able to emit an electron beam into the chamber; an anode that receives the electron beam and that comprises a target that is able to generate ionizing radiation from the energy received from the electron beam; an electrode that is placed in the vicinity of the cathode and that allows the electron beam to be focused; a stopper ensuring the seal tightness of the vacuum chamber; and a mechanical part that is made of dielectric and that forms a portion of the vacuum chamber; and the stopper is fastened to the mechanical part by means of a conductive brazing film that is used to electrically connect the electrode.

A high dose output, through transmission and reflective target x-ray tube and methods of use includes, in general an x-ray tube for accelerating electrons under a high voltage potential having an evacuated high voltage housing, a hemispherical shaped through and reflective transmission target anode disposed in said housing, a cathode structure to deflect the electrons toward the hemispherical anode disposed in said housing, a filament located in the geometric center of the anode hemisphere disposed in said housing, a power supply connected to said cathode to provide accelerating voltage to the electrons.

According to one embodiment, an X-ray computed tomography apparatus includes an X-ray tube, a high voltage power supply, and focus size control circuitry. The X-ray tube includes a cathode, an anode, and a deflector configured to deflect the electrons from the cathode. The high voltage power supply generates a tube voltage to be applied between the cathode and the anode. The focus size control circuitry controls a focus size formed in the anode by applying to the deflector a deflecting voltage of a deflecting voltage value based on a tube voltage value of the tube voltage and a predetermined size, in order to form a focus of the predetermined size in the anode during the period where the tube voltage is applied by the high voltage power supply.

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.

Systems and methods are provided for improving thermal management strategies of a cathode assembly of an x-ray tube. In one embodiment, an x-ray tube comprises an anode assembly and a cathode assembly, wherein the cathode assembly includes one or more elements that include an internal porous section for controlling a flow of heat within the cathode assembly during operation of the x-ray tube. In this way, heat conduction to temperature sensitive aspects of the cathode assembly may be reduced, while enabling sufficient heat transfer to other parts of the cathode assembly to minimize deformation.

According to one embodiment, an X-ray tube includes an anode target, a cathode including a first filament and a converging electrode, and a vacuum envelope. The converging electrode includes a flat front surface, a flat first surface, a first groove portion, and a pair of first protruding portions. The pair of first protruding portions is formed to protrude from the first surface toward the front surface and sandwich the first groove portion in a first length direction. An upper surface is formed of a plurality of flat inclined surfaces.

An x-ray tube having at least one focusing cup and an anode. The x-ray tube may have a first filament positioned in a first location between the focusing cup and the anode, the first filament having a first size, and a second filament positioned in a second location between the focusing cup and anode, the second filament having a second size that is substantially the same as the first size. The x-ray tube may also include a switching mechanism configured to engage the second filament upon failure of the first filament.

Various methods and systems are provided for a cathode cup having a surface texturing to aid in adherence of emitter deposited films. In one embodiment, a method may include chemically and/or mechanically texturing a surface of a cathode cup to form a plurality of features with a higher than threshold depth of each feature, the surface of the cathode cup facing an emitter coupled to the cathode cup.

A apparatus may include a power supply to receive a first voltage potential and output a second voltage potential that is greater than the first voltage potential and a cathode emitter to emit ions in response to application of the second voltage potential. The apparatus may also include a step down transformer to receive the second voltage potential and output a third voltage potential that is less than the second voltage potential. The apparatus may also include a heating element to, in response to application of the third voltage potential, heat the cathode emitter and lower a work function of the cathode emitter.