Abstract: Disclosed herein is a radiation detector configured to absorb radiation particles incident on a semiconductor single crystal of the radiation detector and to generate positive charge carriers and negative charge carriers in the semiconductor single crystal. The semiconductor single crystal may be a cadmium zinc telluride (CdZnTe) single crystal or a cadmium telluride (CdTe) single crystal. The radiation detector comprises a first electrical contact in electrical contact with the semiconductor single crystal and a second electrical contact surrounding the first electrical contact or the semiconductor single crystal. The first electrical contact is configured to collect the negative charge carriers. The second electrical contact is configured to cause the positive charge carriers to drift out of the semiconductor single crystal.

Abstract: Disclosed herein is a computed tomography system, comprising: a table with a hole therein, wherein the table is configured to support a person lying face down thereon, with at least one of the person's breasts projecting through the hole; an X-ray source; an X-ray detector comprising a plurality of pixels; wherein the X-ray source is configured to rotate around the at least one of the person's breasts.

Abstract: An apparatus suitable for detecting X-ray is disclosed. In one example, the apparatus comprises an X-ray absorption layer comprising a first pixel and a second pixel, and a controller. The controller is configured for determining that carriers generated by a single X-ray photon are collected by the first pixel and the second pixel. The controller is also configured for determining energy of the single X-ray photon based on a first voltage detected from the first pixel and a second voltage detected from the second pixel. The first voltage and the second voltage are caused by the single X-ray photon.

Abstract: Disclosed herein is an X-ray imaging system suitable for detecting x-ray, comprising: a first X-ray detector, and a second X-ray detector; wherein the first X-ray detector is configured to move relative to the second X-ray detector; wherein a spatial resolution of the first X-ray detector is higher than a spatial resolution of the second X-ray detector; wherein a detection area of the first X-ray detector is smaller than a detection area of the second X-ray detector. Also described herein is a method of X-ray imaging using the X-ray imaging system.

Abstract: An apparatus suitable for detecting X-ray is disclosed. In one example, the apparatus comprises an X-ray absorption layer and a controller. The X-ray absorption layer comprises a first pixel and a second pixel. The controller is configured for determining that carriers generated by a first X-ray photon are collected by the first pixel and the second pixel, and resetting signals associated with the carriers collected by the first pixel and the second pixel.

Abstract: Disclosed herein is a method for making an apparatus suitable for detecting X-ray, the method comprising: obtaining a wafer and a substrate; wherein the substrate comprises an X-ray absorption layer comprising a first plurality of electrical contacts; wherein the wafer has multiple dies and comprises an electronic layer comprising a second plurality of electrical contacts and an electronic system configured to process or interpret signals generated by X-ray photons incident on the X-ray absorption layer; aligning the first plurality of electrical contacts to the second plurality of electrical contacts; mounting the wafer to the substrate such that the first plurality of electrical contacts are electrically connected to the second plurality of electrical contacts; wherein the substrate further comprises a transmission line electrically bridging at least some of the dies; wherein the second plurality of electrical contacts are configured to feed the signals to the electronic system.

Abstract: Disclosed herein is a radiation detector, comprising: a radiation absorption layer configured to absorb a radiation; a plurality of counters each associated with a bin and configured to register a number of particles of the radiation particles absorbed by the detector; a memory comprising a plurality of units, which can be dynamically allocated to the counters.

Abstract: An apparatus suitable for detecting X-ray is disclosed. In one example, the apparatus comprises an X-ray absorption layer comprising a pixel and a second pixel, and a layer of material or vacuum extending across a thickness of the X-ray absorption layer and encircling the pixel, wherein the layer of material is configured to prevent a charge carrier in the pixel from moving through the layer of material. In another example, the apparatus comprises an X-ray absorption layer comprising a plurality of columns of a semiconductor configured to absorb X-ray, and a layer of material or vacuum extending across a thickness of the X-ray absorption layer and encircling each of the columns, wherein the layer of material is configured to prevent transfer of a charge carrier between two of the columns.

Abstract: Disclosed herein is an apparatus and a method of making the apparatus. The method comprises obtaining a plurality of semiconductor single crystal chunks. Each of the plurality of semiconductor single crystal chunks may have a first surface and a second surface. The second surface may be opposite to the first surface. The method may further comprise bonding the plurality of semiconductor single crystal chunks by respective first surfaces to a first semiconductor wafer. The plurality of semiconductor single crystal chunks forming a radiation absorption layer. The method may further comprise forming a plurality of electrodes on respective second surfaces of each of the plurality of semiconductor single crystal chunks, depositing pillars on each of the plurality of semiconductor single crystal chunks and bonding the plurality of semiconductor single crystal chunks to a second semiconductor wafer by the pillars.

Abstract: Disclosed herein is a system configured to cause an element in a sample to emit fluorescent X-ray, the system comprising a detector with a plurality of pixels, each pixel configured to count numbers of X-ray photons incident thereon whose energy falls in a plurality of bins of different energy ranges respectively, within a period of time; wherein the detector is configured to sum the numbers counted by all the pixels from only the bins of the same energy range; wherein the detector is configured to identify the element based on the summed numbers.

Abstract: Disclosed herein is a method comprising: obtaining a third image from a first X-ray detector when the first X-ray detector and a second X-ray detector are misaligned; determining, based on a shift between a first image and the third image, a misalignment between the first X-ray detector and the second X-ray detector when the first and second detectors are misaligned; wherein the first image is an image the first X-ray detector should capture if the first and the second detectors are aligned.

Abstract: Disclosed herein is a detector, comprising: a plurality of pixels, a plurality of segments of guard ring, and a controller, is configured to count numbers of X-ray photons that incident on each pixel of the plurality, and whose energy falls in a plurality of bins, within a period of time. The controller, is configured to detect charge sharing between pixels and segments of guard ring. With charge sharing detected, the controller is also configured to disregard one single photon. With no charge sharing detected, the controller is configured to add the numbers of X-ray photons that incident on the all pixels, for the bins of the same energy range. The detector may compile all the added numbers as an energy spectrum of the incident X-ray photons thereon.

Abstract: Disclosed herein is a method, comprising: exposing an image sensor to a scene; measuring, as analog signals, intensities of light from the scene by a plurality of pixels of the image sensor; converting the analog signals to digital signals; and determining a total intensity of light of the scene by calculating a sum of the digital signals.

Abstract: Disclosed herein is an apparatus comprising: a radiation absorption layer comprising an electrode; a counter configured to register a number of radiation particles absorbed by the radiation absorption layer; a controller configured to start a time delay from a time at which an absolute value of an electrical signal on the electrode equals or exceeds an absolute value of a first threshold; wherein the controller is configured to cause the number registered by the counter to change, in response to the absolute value of the electrical signal equaling or exceeding an absolute value of a second threshold during the time delay.

Abstract: Disclosed herein is an apparatus comprising: an array of avalanche photodiodes (APDs), each of the APDs comprising an absorption region and an amplification region; wherein the absorption region is configured to generate charge carriers from a photon absorbed by the absorption region; wherein the amplification region comprises a junction with an electric field in the junction; wherein the electric field is at a value sufficient to cause an avalanche of charge carriers entering the amplification region, but not sufficient to make the avalanche self-sustaining; wherein the junctions of the APDs are discrete.

Abstract: Disclosed herein is a system comprising multiple layers of X-ray detectors. The top layer may have through-wafer vias. The other layers may have bonding wires. The bonding wires are shadowed by the X-ray absorption layers in the layers above.

Abstract: Disclosed herein is a method comprising: obtaining a substrate comprising an electronic system in or on the substrate, and a plurality of electric contacts on a first surface of the substrate, the electronic system being electrically connected to the electric contacts; obtaining a chip comprising an X-ray absorption layer, the X-ray absorption layer comprising an electrode; electrically connecting the electrode to at least one of the electric contacts by bonding the chip to the substrate; and thinning the substrate at a surface opposite the first surface.

Abstract: The present teaching relates to methods, systems, and apparatus for X-ray imaging with a detector capable of resolving photon energy. In one example, an X-ray microscope is disclosed. The X-ray microscope comprises an X-ray source and a detector. The X-ray source is configured for irradiating X-ray to a sample. The detector is configured for: detecting X-ray photons from the irradiated X-ray, determining energy of each of the detected X-ray photons, and generating an image of the sample based on detected X-ray photons that have energies in a predetermined range.