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.

According to some aspects, a carrier configured for use with a broadband x-ray source comprising an electron source and a primary target arranged to receive electrons from the electron source to produce broadband x-ray radiation in response to electrons impinging on the primary target is provided. The carrier comprising a housing configured to be removeably coupled to the broadband x-ray source and configured to accommodate a secondary target capable of producing monochromatic x-ray radiation in response to incident broadband x-ray radiation, the housing comprising a transmissive portion configured to allow broadband x-ray radiation to be transmitted to the secondary target when present, and a blocking portion configured to absorb broadband x-ray radiation.

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.

An X-ray tube including a vacuum vessel, a cathode and an anode fixedly disposed inside the vacuum vessel, and a rotary mechanism that rotates the vacuum vessel, where the cathode is disposed on the circumference with a rotary shaft of the rotary mechanism as its center and includes multiple cathode parts that can individually be turned ON/OFF, and where the anode includes parts opposite to the multiple cathode parts, respectively.

According to some aspects, a carrier configured for use with a broadband x-ray source comprising an electron source and a primary target arranged to receive electrons from the electron source to produce broadband x-ray radiation in response to electrons impinging on the primary target is provided. The carrier comprising a housing configured to be removeably coupled to the broadband x-ray source and configured to accommodate a secondary target capable of producing monochromatic x-ray radiation in response to incident broadband x-ray radiation, the housing comprising a transmissive portion configured to allow broadband x-ray radiation to be transmitted to the secondary target when present, and a blocking portion configured to absorb broadband x-ray radiation.

An X-ray generator includes an X-ray tube, an X-ray tube accommodation portion, and a power source unit having an internal substrate supplying a voltage to the X-ray tube sealed inside an insulating block. Insulating oil is enclosed in a space defined by an upper surface of the insulating block and an inner surface of the X-ray tube accommodation portion. A high-voltage power supply unit connected to a target support portion is disposed on the upper surface. At least one protrusion portion protruding to an insulating valve side beyond a boundary portion where the high-voltage power supply unit, the upper surface, and the insulating oil meet and surrounding the high-voltage power supply unit is provided on the upper surface. An apex portion of the protrusion portion is separated from an imaginary plane including an end portion of the insulating valve and extending in a direction orthogonal to a tube axis.

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.

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.

An X-ray generator includes an X-ray tube, an X-ray tube accommodation portion, and a power source unit having an internal substrate supplying a voltage to the X-ray tube sealed inside an insulating block. Insulating oil is enclosed in a space defined by an upper surface of the insulating block and an inner surface of the X-ray tube accommodation portion. A high-voltage power supply unit connected to a target support portion is disposed on the upper surface. At least one protrusion portion protruding to an insulating valve side beyond a boundary portion where the high-voltage power supply unit, the upper surface, and the insulating oil meet and surrounding the high-voltage power supply unit is provided on the upper surface. An apex portion of the protrusion portion is separated from an imaginary plane including an end portion of the insulating valve and extending in a direction orthogonal to a tube axis.