Abstract: Disclosed herein is a radiation detector, comprising: an avalanche photodiode (APD) with a first side coupled to an electrode and configured to work in a linear mode; a capacitor module electrically connected to the electrode and comprising a capacitor, wherein the capacitor module is configured to collect charge carriers from the electrode onto the capacitor; a current sourcing module in parallel to the capacitor, the current sourcing module configured to compensate for a leakage current in the APD and comprising a current source and a modulator; wherein the current source is configured to output a first electrical current and a second electrical current; wherein the modulator is configured to control a ratio of a duration at which the current source outputs the first electrical current to a duration at which the current source outputs the second electrical current.

Abstract: Disclosed herein are apparatuses for detecting radiation and methods of making them. The method comprises forming a recess into a semiconductor substrate, wherein a portion of the semiconductor substrate extends into the recess and is surrounded by the recess; depositing semiconductor nanocrystals into the recess, the semiconductor nanocrystals having a different composition from the semiconductor substrate; forming a first doped semiconductor region in the semiconductor substrate; forming a second doped semiconductor region in the semiconductor substrate; wherein the first doped semiconductor region and the second doped semiconductor region form a p-n junction that separates the portion from the rest of the semiconductor substrate.

Abstract: Disclosed herein is a detector having a pixel in a substrate and configured to detect radiation particles incident thereon; a first guard ring in the substrate, surrounding the pixel, and comprising a first doped semiconductor region in the substrate and a first electrically conductive layer in electrical contact to the first doped semiconductor region. The first electrically conductive layer overhangs the first doped semiconductor region toward an interior of the first guard ring.

Abstract: Disclosed herein is an apparatus suitable for detecting radiation, comprising: a plurality of pixels configured to generate an electric signal upon exposure to a radiation; an electronic system configured to read out the electric signal; wherein the electronic system comprises a first memory and a second memory; wherein the first memory is configured to store a plurality of data bits representing the electric signal generated by the pixel that the first memory is associated with; wherein the electronic system is configured to transmit a subset of bits among the plurality of data bits, from the first memory to the second memory; wherein the electronic system is configured to transmit the subset of bits from the second memory to a bus.

Abstract: Disclosed herein are various methods of packaging a semiconductor X-ray detector. The methods may include bonding chips including an X-ray absorption layer or including both an X-ray absorption layer and an electronic layer onto another support such as an interposer substrate or a printed circuit board.

Abstract: Disclosed herein is an apparatus suitable for detecting x-ray, comprising: an X-ray absorption layer configured to generate an electrical signal from an X-ray photon incident on the X-ray absorption layer; an electronics layer comprising an electronics system configured to process or interpret the electrical signal; and an interposer chip embedded in a board of an electrically insulating material; wherein the X-ray absorption layer is bonded to the electronics layer; wherein the electronics layer is bonded to the interposer chip.

Abstract: Disclosed herein is a method, comprising: for i=1, . . . , M, sending a pencil radiation beam (i) toward an image sensor, wherein the pencil radiation beam (i) is incident on an incident region (i) on an active area of the image sensor, wherein the pencil radiation beam (i) is aimed at a target region (i) on the active area, wherein M is a positive integer, for i=1, . . . , M, determining an offset (i) between the incident region (i) and the target region (i).

Abstract: Disclosed herein is an endoscope comprising: an insertion tube; a radiation detector configured to detect radiation particles in a first range of energy and radiation particles in a second range of energy.

Abstract: Disclosed herein is a radiation detector, comprising: an avalanche photodiode (APD) with a first side coupled to an electrode and configured to work in a linear mode; a capacitor module electrically connected to the electrode and comprising a capacitor, wherein the capacitor module is configured to collect charge carriers from the electrode onto the capacitor; a current sourcing module in parallel to the capacitor, the current sourcing module configured to compensate for a leakage current in the APD and comprising a current source and a modulator; wherein the current source is configured to output a first electrical current and a second electrical current; wherein the modulator is configured to control a ratio of a duration at which the current source outputs the first electrical current to a duration at which the current source outputs the second electrical current.

Abstract: Disclosed herein is a method for forming a radiation detector. The method comprises forming a radiation absorption layer and bonding an electronics layer to the radiation absorption layer. The electronics layer comprises an electronic system configured to process electrical signals generated in the radiation absorption layer upon absorbing radiation photons. The method for forming the radiation absorption layer comprises forming a trench into a first surface of a semiconductor substrate; doping a sidewall of the trench; forming a first electrical contact on the first surface; forming a second electrical contact on a second surface of the semiconductor substrate. The second surface is opposite the first surface. The method further comprises dicing the semiconductor substrate along the trench.

Abstract: Disclosed herein is a method for forming a radiation detector. The method comprises forming a radiation absorption layer and bonding an electronics layer to the radiation absorption layer. The electronics layer comprises an electronic system configured to process electrical signals generated in the radiation absorption layer upon absorbing radiation photons. The method for forming the radiation absorption layer comprises forming a trench into a first surface of a semiconductor substrate; doping a sidewall of the trench; forming a first electrical contact on the first surface; forming a second electrical contact on a second surface of the semiconductor substrate. The second surface is opposite the first surface. The method further comprises dicing the semiconductor substrate along the trench.

Abstract: Disclosed herein is a method comprising: forming electrical contacts on a first surface of an epitaxial layer supported on a substrate, the first surface being opposite from the substrate; bonding the epitaxial layer to an electronics layer, wherein the first surface faces the electronics layer and the electrical contacts on the first surface are bonded to electrical contacts of the electronics layer; exposing a second surface opposite the first surface by removing the substrate; and forming a common electrode on the second surface.

Abstract: Disclosed herein is a detector, comprising: a plurality of pixels, each pixel configured to count numbers of X-ray photons incident thereon whose energy falls in a plurality of bins, within a period of time; an X-ray absorption layer; wherein the X-ray absorption layer comprises an electrical contact within each of the pixels, and a focusing electrode surrounding the electrical contact and configured to direct to the electrical contact charge carriers generated by an X-ray photon incident within confines of the focusing electrodes; and wherein the detector is configured to add the numbers of X-ray photons for the bins of the same energy range counted by all the pixels.

Abstract: An apparatus for detecting X-ray, comprising an X-ray absorption layer comprising an electrode, an electronics layer and a wall sealing a space among electrical connections between the X-ray absorption layer and the electronics layer. The electronics layer comprises: a first and second voltage comparators configured to compare a voltage of an electrode to a first and second thresholds respectively; a counter configured to register a number of X-ray photons absorbed by the X-ray absorption layer; and a controller configured to: start a time delay from a time at which an absolute value of the voltage equals or exceeds an absolute value of the first threshold; activate the second voltage comparator during the time delay; cause the number registered by the counter to increase by one, if, during the time delay, an absolute value of the voltage equals or exceeds an absolute value of the second threshold.

Abstract: Disclosed herein is a method, comprising: for i=1, . . . , M, sending a pencil radiation beam (i) toward an image sensor, wherein the pencil radiation beam (i) is incident on an incident region (i) on the image sensor, wherein the pencil radiation beam (i) is aimed at a target region (i) on the image sensor, wherein M is a positive integer, wherein the image sensor comprises active areas spatially discontinuous from each other, and wherein the incident regions (i), i=1, . . . , M and the target regions (i), i=1, . . . , M are on the active areas; and for i=1, . . . , M, determining an offset (i) between the incident region (i) and the target region (i).

Abstract: Disclosed herein is a method comprising: obtaining a signal at a pixel in an array of pixels of a radiation detector, wherein the signal is generated from radiation incident on the radiation detector; obtaining a corrected signal by correcting the signal with a combination of a set of reference signals generated from the radiation at a set of reference pixels in the array, wherein a set of weights are respectively applied to the set of reference signals in the combination; and forming an image based on the corrected signal; wherein the set of weights is a function of a location of the pixel with respect to the array.

Abstract: An apparatus, system and method suitable for detecting X-ray are disclosed. In one example, the apparatus comprises: an X-ray absorption layer and a mask; wherein the mask comprises a first window and a second window, and a portion between the first window and the second window; wherein the first and second windows are not opaque to an incident X-ray; wherein the portion is opaque to the incident X-ray; and wherein the first and second windows are arranged such that charge carriers generated in the X-ray absorption layer by an X-ray photon propagating through the first window and charge carriers generated in the X-ray absorption layer by an X-ray photon propagating through the second window do not spatially overlap.

Abstract: Disclosed herein is an apparatus comprising: an X-ray source configured to direct X-rays through a human tissue; an X-ray detector configured to capture an image of the human tissue with the X-rays; wherein the apparatus is configured to identify an image of a blood vessel from the image of the human tissue and configured to determine a blood sugar level based on the image of the blood vessel.

Abstract: Disclosed herein is a method, comprising: causing emission of characteristic X-rays of a chemical element in an object by directing radiation to the object; capturing images of the object using the radiation that has transmitted through the object; capturing images of the chemical element in the object using the characteristic X-rays; reconstructing a three-dimensional image of the object based on the images of the object; determining a three-dimensional distribution of the chemical element in the object based on the images of the chemical element; and superposing the three-dimensional image of the object and the three-dimensional distribution of the chemical element in the object to form a superposed image of the object. The radiation directed to the object comes from multiple radiation sources. The images are captured with multiple image sensors. The radiation sources and the image sensors are stationary with respect to the object.

Abstract: Disclosed herein is a method comprising: forming a doped region of a semiconductor substrate by doping a surface of the semiconductor substrate with dopants; driving the dopants into the semiconductor substrate by annealing the semiconductor substrate; controlling doping profile of the doped region by repeating doping and annealing the semiconductor substrate; forming a first electrode on the semiconductor substrate, wherein the first electrode is in electrical contact with the doped region; forming an outer electrode arranged around the first electrode, wherein the outer electrode is electrically insulated from the first electrode.