A photon counting detector and CT imaging system

Abstract

The application relates to a photon counting detector and a CT imaging system. The photon counting detector comprises a detection medium, a signal processing chip and a conductive layer. The detection medium comprises a plurality of pixels, each of which is used for converting incident X-ray radiation into an electrical signal. The signal processing chip is used for processing the electrical signal. One end of the conductive layer is connected to the pixels of the detection medium, and the other end is connected to the pins of the signal processing chip. The conductive layer is a flexible conductive layer. By setting the conductive layer as a flexible conductive layer, the advantages of the two materials can be considered. The electrical conductivity can be used to realize the interconnection of the high-density pixel detection medium and the signal processing chip, and the flexibility of the material can be used to cope with the internal stress introduced by environmental changes, thereby improving the reliability of the photon counting detector module.

Description

Technical Field

[0001] This application relates to the field of medical device technology, and in particular to a photon counting detector and a CT imaging system incorporating the photon counting detector. Background Technology

[0002] Photon counting detectors are widely used in fields such as medical imaging and high-energy physics. Currently, the mainstream technology of semiconductor photon counting detectors still uses compound semiconductor materials (such as tellurium, zinc, cadmium, and cadmium telluride) as the detection medium, and combines them with ASICs based on semiconductor materials to realize X-ray detection and signal processing respectively. The detection medium and signal processing chip are fabricated separately, and then the interconnection of the detection medium and signal processing chip is realized through packaging technology.

[0003] In hybrid semiconductor pixel detector structures, the probe medium and the signal processing chip (ASIC) are two distinct components with different coefficients of thermal expansion and surface warpage characteristics. When external environmental conditions (such as temperature, humidity, vibration, etc.) change, these two components expand or contract at different rates and amplitudes, generating thermal stress. This thermal stress can damage the electrical connections between them, ultimately causing reliability issues in the detector module and affecting the detector's stability and lifespan.

[0004] Existing technologies typically employ rigid connection methods, such as welding and conductive adhesives. These methods lack sufficient elastic deformation capacity in response to environmental changes, failing to effectively alleviate thermal stress and leading to easy breakage or poor contact at the connection points. Therefore, there is an urgent need for a flexible connection structure that can adapt to environmental changes and alleviate thermal stress, in order to improve the reliability and stability of photon counting detectors. Utility Model Content

[0005] Therefore, it is necessary to address the reliability issues of detector modules by providing a photon counting detector and a CT imaging system containing the photon counting detector, which has the advantages of allowing a certain degree of relative displacement or deformation at the connection points, absorbing or buffering stress, vibration or thermal expansion in the system, reducing environmental-induced electrical connection failures, and improving detector reliability.

[0006] To address the aforementioned technical problems and improve the reliability of the photon counting detector module, this application provides a photon counting detector, comprising a detection medium, a signal processing chip, and a conductive layer. The detection medium includes multiple pixels, each pixel converting incident X-ray radiation into an electrical signal. The signal processing chip processes the electrical signal. One end of the conductive layer is connected to a pixel in the detection medium, and the other end is connected to a pin of the signal processing chip. The conductive layer is a flexible conductive layer.

[0007] Preferably, the conductive layer is composed of a combination of organic flexible material and conductive filler, and the conductive layer is a flexible conductive sphere or anisotropic conductive film.

[0008] Furthermore, the flexible conductive sphere comprises a metal layer and an insulating sphere, wherein the metal layer is a conductive filler, the insulating sphere is a flexible polymeric organic material, and the metal layer covers the outer surface of the insulating sphere.

[0009] Furthermore, the anisotropic conductive film comprises an insulating layer and a conductive medium; the insulating layer is a flexible polymeric organic material, and the conductive medium is formed by bonding together multiple conductive particles or by combining multiple conductive metal wires; the conductive medium is embedded in the insulating layer.

[0010] Furthermore, the conductive medium has two ends protruding from the insulating layer, with one end of the conductive medium soldered to the pixel of the detection medium and the other end soldered to the pin of the signal processing chip.

[0011] Furthermore, the diameter of the flexible conductive ball is less than or equal to the width of the pixel of the detection medium, or the width of the conductive medium is less than or equal to the width of the pixel of the detection medium.

[0012] This application also provides another photon counting detector, comprising: a detection medium including a plurality of pixels configured to convert incident X-ray radiation into electrical signals; a signal processing chip including a plurality of processing units, each processing unit corresponding to one of the pixels; the processing units and the pixels being connected via a flexible conductive layer material or an elastic conductive material.

[0013] Preferably, the processing unit is connected to the pixel via a flexible conductive layer material, the flexible conductive layer material comprising an organic flexible material and a metal layer covering the organic flexible material.

[0014] Furthermore, the processing unit is connected to the pixel via a flexible conductive layer material, which includes an organic flexible material and conductive particles embedded in the organic flexible material.

[0015] This application also provides a CT imaging system including the aforementioned photon counting detector.

[0016] In the aforementioned photon counting detector, the photon counting detector includes a detection medium, a signal processing chip, and a conductive layer. The detection medium includes multiple pixels, each of which converts incident X-ray radiation into an electrical signal. The signal processing chip processes the electrical signal. One end of the conductive layer is connected to the pixel of the detection medium, and the other end is connected to a pin of the signal processing chip. The conductive layer is a flexible conductive layer. In this embodiment, by setting the conductive layer as a flexible conductive layer, the advantages of both materials can be combined. Its conductivity allows for high-density interconnection between the pixel detection medium and the signal processing chip, while its flexibility can cope with internal stress introduced by environmental changes, thereby improving the reliability of the photon counting detector module. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments of this application or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is an overall structural diagram of a photon counting detector in one embodiment;

[0019] Figure 2 This is a schematic diagram of a photon counting detector in one embodiment of this application, where the conductive layer is a flexible conductive sphere;

[0020] Figure 3 This is a schematic diagram of an anisotropic conductive film as the conductive layer of a photon counting detector in another embodiment of this application.

[0021] Reference numerals: Detector medium 11, Signal processing chip 12, Conductive layer 13, Metal layer 22, Insulating sphere 21, Conductive medium 32, Insulating layer 31. Detailed Implementation

[0022] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0023] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0024] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0025] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0026] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0027] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0028] Photon-counting computed tomography (PCCT) is a novel medical imaging technique that utilizes a photon-counting detector (PCD) to directly measure the energy of each incident X-ray photon, rather than the energy integration mode of traditional CT. By distinguishing photons of different energies, PCCT offers advantages such as multi-spectral imaging, material composition identification, and low-dose, high-resolution imaging.

[0029] Photon counting detectors are typically semiconductor pixel detectors, which can be structurally divided into hybrid semiconductor pixel detectors and monolithically integrated semiconductor pixel detectors. The former allows for more flexible integration between the detection medium and the signal processing ASIC, while the latter can achieve higher pixel density. For CT, since the current mainstream technology for semiconductor photon counting detectors still uses compound semiconductor materials (such as zinc cadmium telluride and cadmium telluride) as the detection medium, and combines them with silicon semiconductor-based ASICs to realize X-ray detection and signal processing respectively, a monolithically integrated structure cannot be used. Instead, the detection medium and readout chip are fabricated separately, and then the interconnection between the pixelated detection medium and the ASIC is achieved through high-density packaging technology.

[0030] See Figure 1 , Figure 1 A schematic diagram of a photon counting detector according to an embodiment of this application is shown. This embodiment provides a photon counting detector comprising: a detection medium 11 including multiple pixels, each pixel being used to convert incident X-ray radiation into an electrical signal; a signal processing chip 12 for processing the electrical signal; and a conductive layer 13, one end of which is connected to a pixel of the detection medium 11, and the other end of which is connected to a pin of the signal processing chip 12. The conductive layer 13 is a flexible conductive layer.

[0031] The photon counting detector includes a detection medium 11, which is mainly used to convert incident X-ray radiation into electrical signals. The detection medium 11 is a semiconductor material, such as CdTe, CdZnTe, GaAs, or Si. The detector is divided into multiple electrodes, with each electrode being a pixel. Therefore, the detection medium 11 is divided into multiple photon detector pixels, each of which can independently receive X-ray signals and generate corresponding electrical signals. These pixels are usually arranged in an array to form the sensing area of ​​the detector. When X-rays irradiate the detection medium 11, electron-hole pairs are generated in the semiconductor material. Under the influence of an electric field, these charges are collected and form electrical signals. Specific materials for the detection medium include commonly used high atomic number, high-density semiconductors such as tellurium (Cd), zinc (Zn), and cadmium (Te), suitable for high-energy X-rays (such as medical CT), with excellent quantum efficiency and energy resolution; silicon (Si), used for low-energy photons (such as small animal imaging or synchrotron radiation), which is low in cost and easy to process; and gallium arsenide (GaAs) or cadmium selenide (CdSe), optimized for specific energy spectra. The structure of the detector medium 11 is typically a pixel array (such as pixels ranging from 0.1*0.1 mm² to 1*1 mm²). A pixel is the smallest independent detection unit in the detector array, responsible for capturing a single X-ray photon and generating a corresponding electrical signal. Each pixel responds to the photon independently, avoiding signal crosstalk.

[0032] The signal processing chip 12 includes multiple processing units, each with pins that are connected one-to-one with the pixels of the detection medium 11. The signal processing chip 12 receives electrical signals from the detection medium 11, amplifies, shapes, filters, and converts these signals into digital signals for output. The signal processing chip 12 can be an application-specific integrated circuit (ASIC) or other types of signal processing circuits. Its core modules include: a preamplifier that converts weak charge signals (fC level) into voltage pulses; a pulse shaper that optimizes the signal-to-noise ratio and limits the pulse width to avoid pile-up; a threshold discriminator that sets energy thresholds and counts only photons exceeding the threshold, supporting multi-level analysis (e.g., 58 energy thresholds); and a counter and data buffer that classifies and counts photons according to energy thresholds and outputs the data to the backend system in real time.

[0033] The conductive layer 13 is connected at one end to a pixel on the detection medium 11 and at the other end to a pin on the signal processing chip 12, for transmitting electrical signals between the detection medium 11 and the signal processing chip 12. The conductive layer 13 is a flexible conductive layer, composed of a combination of a flexible polymeric organic material and conductive fillers. The flexible polymeric organic material provides the conductive layer 13 with flexibility, allowing it to adapt to any slight height differences or unevenness that may exist between the detection medium 11 and the signal processing chip 12, ensuring a good electrical connection. The conductive fillers provide the conductive properties of the conductive layer 13, enabling the smooth transmission of electrical signals.

[0034] In this embodiment, the polymeric organic flexible material of the flexible conductive layer is typically an insulating material with a certain degree of elasticity and stable molecular structure, such as silicone rubber, polyurethane, polypropylene, or polyethylene. The conductive filler is typically a conductive material with high conductivity, resistance to oxidation, and a certain degree of elasticity, such as metal particles, metal fibers, carbon nanotubes, or graphene. By mixing the polymeric organic flexible material and the conductive filler in a certain proportion, a flexible conductive layer with good flexibility and conductivity can be obtained.

[0035] Compared with existing technologies, this embodiment sets the conductive layer as a flexible conductive layer composed of a combination of polymeric organic flexible material and conductive filler. This can take into account the advantages of both materials. It can utilize the conductivity to achieve high-density interconnection between the pixel detection medium and the signal processing chip, and utilize the flexibility of the material to cope with the internal stress introduced by environmental changes, thereby improving the reliability of the photon counting detector module.

[0036] In one embodiment, the conductive layer (13) is composed of a combination of organic flexible material and conductive filler, and the conductive layer 13 is a flexible conductive sphere or anisotropic conductive film.

[0037] like Figure 2 The diagram illustrates a photon counting detector in one embodiment of this application, where the conductive layer is a flexible conductive sphere. In this embodiment, the conductive layer is a flexible conductive sphere comprising a metal layer 22 and an insulating sphere 21. The metal layer 22 is a conductive filler, and the insulating sphere 21 is a flexible polymeric organic material. The metal layer 22 covers the outer surface of the insulating sphere 21. The insulating sphere 21 can be a tiny sphere made of polymeric materials such as silicone rubber or polyurethane, possessing a certain degree of elasticity and flexibility. The metal layer 22 can be a metal material such as gold, silver, copper, or nickel, which is coated onto the outer surface of the insulating sphere 21 through electroplating, chemical deposition, or other methods to form a conductive outer shell.

[0038] One end of the flexible conductive sphere is soldered to a pixel of the detection medium 11, and the other end is soldered to a pin of the signal processing chip 12. Because the insulating sphere 21 is elastic, when there is a slight height difference or unevenness between the detection medium 11 and the signal processing chip 12, the flexible conductive sphere can adapt to this difference through its own deformation, ensuring the reliability of the electrical connection. At the same time, the metal layer 22 provides a good conductive path, enabling the smooth transmission of electrical signals.

[0039] In this embodiment, the diameter of the flexible conductive ball is less than or equal to the width of a pixel in the detection medium 11. This design ensures that each flexible conductive ball connects to only one pixel, avoiding signal interference between adjacent pixels. For example, if the pixel width of the detection medium 11 is 100 micrometers, the diameter of the flexible conductive ball should not exceed 100 micrometers. In practical applications, a suitable diameter flexible conductive ball can be selected based on the specific size of the pixel. If adjacent pixels are conductive, they will establish an electrical connection, leading to severe crosstalk between channels. The back-end ASIC circuit cannot distinguish the source of the signal, causing signal chain disorder.

[0040] Specifically, for example, the insulating sphere 21 is made of silicone rubber and has a diameter of 50 micrometers. Silicone rubber has good elasticity and temperature resistance, and can maintain stable mechanical properties over a wide temperature range. The metal layer 22 adopts a nickel-gold double-layer structure, with an inner nickel layer of 2 micrometers thickness and an outer gold layer of 0.5 micrometers thickness. The nickel layer provides good adhesion and mechanical strength, while the gold layer provides excellent electrical conductivity and oxidation resistance.

[0041] The flexible conductive ball is connected to the pixels of the detection medium 11 and the pins of the signal processing chip 12 by a soldering process. Specifically, solder paste is first applied to the pixels of the detection medium 11 and the pins of the signal processing chip 12, then the flexible conductive ball is placed on the solder paste, and finally the solder paste is melted by a reflow soldering process to form a strong solder connection with the metal layer 22 of the flexible conductive ball.

[0042] In this embodiment, the pixel width of the detection medium 11 is 100 micrometers, and the diameter of the flexible conductive ball is 50 micrometers, which is smaller than the pixel width. This ensures that each flexible conductive ball is connected to only one pixel, thus avoiding signal interference between adjacent pixels.

[0043] In this embodiment, the diameter of the flexible conductive ball is 30 micrometers, which is smaller than the pixel width of the detection medium 11 (100 micrometers). To improve the reliability of the connection, multiple flexible conductive balls are placed on each pixel to form a redundant connection. Specifically, four flexible conductive balls are evenly distributed on each pixel, and these flexible conductive balls are connected to the pixel and the pins of the signal processing chip 12 through a soldering process.

[0044] The use of multiple flexible conductive balls improves connection reliability. Even if one flexible conductive ball fails, the others can still maintain electrical connection, ensuring normal signal transmission. At the same time, the uniform distribution of multiple flexible conductive balls reduces the mechanical stress on each individual ball, extending the connection's lifespan.

[0045] Compared with traditional rigid conductive connection methods, flexible conductive spheres have the following advantages: By using a flexible conductive sphere as the conductive layer and a metal layer covering the surface of the insulating sphere, the conductivity of the metal layer can be used to interconnect high-density pixel detection media and signal processing chips. The flexible conductive sphere can adapt to small height differences and unevenness between the detection media and the signal processing chip, improving the reliability of the connection. The elastic properties of the flexible conductive sphere can alleviate the stress caused by the mismatch of thermal expansion coefficients and reduce connection failures caused by temperature changes.

[0046] like Figure 3 As shown, the photon counting detector provided in this embodiment is basically the same as that described above, except for the specific form of the conductive layer 13. In this embodiment, the conductive layer 13 is an anisotropic conductive film. The anisotropic conductive film includes an insulating layer 31 and a conductive medium 32; the insulating layer 31 is a flexible polymer organic material, and the conductive medium 32 is a conductive filler; the conductive medium 32 is embedded in the insulating layer 31.

[0047] Anisotropic conductive film (ACF) is a flexible bonding material that conducts electricity in the vertical direction and is insulating in the lateral direction. The insulating layer is made of a flexible polymer organic material to form a lateral insulating plate, and conductive fillers, such as conductive particles or conductive metals, are embedded in the insulating plate. This allows the flexible polymer material to adapt to differences in thermal expansion or mechanical deformation.

[0048] In this embodiment, the conductive medium 32 protrudes from the insulating layer 31 at both ends. One end of the conductive medium 32 is soldered to the pixel of the detection medium 11, and the other end is soldered to the pin of the signal processing chip 12. The protrusion of the conductive medium 32 from the insulating layer 31 at both ends enables directional conductivity. This structural design allows the conductive medium 32 to form a reliable electrical connection with the pixel of the detection medium 11 and the pin of the signal processing chip 12, while the insulating layer 31 provides mechanical support and electrical insulation.

[0049] The conductive medium 32 is composed of multiple conductive particles bonded together, or of multiple conductive metal wires combined. When conductive particles are used, these particles can be metals such as gold, silver, copper, and nickel, or carbon-based materials such as carbon nanotubes and graphene. These conductive particles are fixed together with an adhesive to form a conductive path. When conductive metal wires are used, these wires can be fine metal wires made of metals such as gold, silver, copper, and nickel, which are arranged in parallel to form a conductive path.

[0050] The conductive metal wire extends beyond the insulating layer 31 at both ends. One end is soldered to the pixel of the detection medium 11, and the other end is soldered to the pin of the signal processing chip 12. The soldering process uses ultrasonic welding, which can achieve a strong connection between metals at low temperatures, avoiding damage to the detection medium 11 and the signal processing chip 12 caused by high temperatures.

[0051] In this embodiment, the pixel width of the detection medium 11 is 100 micrometers, and the width of the conductive medium 32 is 60 micrometers, which is smaller than the pixel width. This ensures that each conductive medium 32 connects to only one pixel, thus avoiding signal interference between adjacent pixels.

[0052] In this embodiment, the width of the conductive medium 32 is less than or equal to the width of a pixel in the detection medium 11. Specifically, when the conductive medium is conductive particles, the width of the particles must be less than or equal to the pixel width. When the conductive medium is conductive metal wire, the conductive metal wire can be oriented to form a three-dimensional shape, such as a cylinder or cube. The width of the three-dimensional conductive metal wire must be less than or equal to the width of a pixel in the detection medium. The purpose of this design is to ensure that each conductive medium 32 connects only one pixel, avoiding signal interference between adjacent pixels. For example, if the pixel width of the detection medium 11 is 100 micrometers, then the width of the conductive medium 32 should not exceed 100 micrometers. In practical applications, a suitable width of conductive medium 32 can be selected according to the specific size of the pixel.

[0053] Specifically, for example, in anisotropic conductive films, the insulating layer 31 is made of polyurethane material with a thickness of 30 micrometers. Polyurethane material has good flexibility and insulation properties, and can maintain stable mechanical properties over a wide temperature range. The conductive dielectric 32 is made of bonded metal particles, which are gold-plated copper particles with a diameter of 5 micrometers, and have a distribution density of 10,000 particles per square millimeter in the insulating layer 31.

[0054] Specifically, the conductive medium 32 is composed of multiple conductive metal wires. These conductive metal wires are gold-plated copper wires with a diameter of 10 micrometers, arranged in parallel within the insulating layer 31, with a spacing of 20 micrometers between adjacent wires. This structural design enables the conductive medium 32 to have good conductivity in the vertical direction while maintaining insulation in the horizontal direction, thus avoiding signal interference between adjacent pixels.

[0055] Compared with traditional rigid conductive connection methods, anisotropic conductive films can adapt to the small height difference and unevenness between the detection medium 11 and the signal processing chip, thus improving the reliability of the connection. Secondly, the flexible properties of anisotropic conductive films can alleviate the stress caused by the mismatch of thermal expansion coefficients and reduce connection failures caused by temperature changes.

[0056] In another embodiment, the pixel structure of the probe medium 11 and the connection of the conductive layer 13 are as follows: the probe medium 11 is made of GaAs semiconductor material and has a thickness of 0.5 mm. An aluminum electrode is deposited on the upper surface of the probe medium 11 to form a cathode; a gold electrode is deposited on the lower surface to form an anode, and the medium is divided into a 16×16 pixel array, with each pixel measuring 0.5 mm × 0.5 mm. A 50-micrometer-wide isolation trench is provided between the pixels to reduce charge sharing effects between adjacent pixels.

[0057] The signal processing chip 12 is an application-specific integrated circuit (ASIC) containing 256 signal processing channels, each corresponding to one pixel. The signal processing chip 12 is manufactured using a 0.13-micron CMOS process and has a chip size of 8 mm × 8 mm.

[0058] The conductive layer 13 uses flexible conductive balls to connect the pixels of the detection medium 11 and the pins of the signal processing chip 12. The diameter of the flexible conductive balls is 30 micrometers, much smaller than the pixel size of 0.5 millimeters, ensuring the accuracy and reliability of the connection. To improve the reliability of the connection, nine flexible conductive balls are evenly distributed on each pixel to form a redundant connection.

[0059] In one embodiment, a photon counting detector includes a detection medium and a signal processing chip. The detection medium includes a plurality of photodetector pixels configured to convert incident X-ray radiation into electrical signals. The signal processing chip includes a plurality of processing units, each corresponding one-to-one with a photodetector pixel. The processing units and photodetector pixels are connected through a flexible conductive layer material or an elastic conductive material.

[0060] In this embodiment, the detection medium is made of a high-purity semiconductor material, such as CdTe, CdZnTe, GaAs, or Si. Multiple pixels are formed on the detection medium, arranged in a two-dimensional array. The size of each pixel can range from 50μm*50μm to 200μm*200μm. When X-ray radiation is incident on the detection medium, electron-hole pairs are generated in the semiconductor material, forming an electrical signal.

[0061] The signal processing chip is manufactured using CMOS technology and contains multiple processing units, each corresponding to one pixel. Each processing unit includes circuit modules such as a preamplifier, shaping amplifier, comparator, and counter, which amplify, shape, and count the electrical signals generated by the photodetector pixels to achieve photon counting.

[0062] The processing unit and the pixel are connected via a flexible conductive layer material, which includes an organic flexible material and a metal layer covering the organic flexible material. The organic flexible material can be a polymer such as polyimide, polyurethane, or epoxy resin, which has good elasticity and heat resistance. The metal layer can be a metal with good conductivity such as gold, silver, copper, or nickel, which is coated onto the surface of the organic flexible material through processes such as electroplating or vapor deposition to form a conductive path.

[0063] Alternatively, the processing unit and the photodetector pixels are connected via a flexible conductive layer material, which includes an organic flexible material and conductive particles embedded in the organic flexible material. The organic flexible material can also be a polymer such as polyimide, polyurethane, or epoxy resin. The conductive particles can be metal particles such as gold, silver, copper, or nickel, or carbon-based conductive materials such as carbon nanotubes or graphene, uniformly distributed within the organic flexible material to form a conductive network.

[0064] In one embodiment, a CT imaging system is included, comprising a photon-counting detector as described in the foregoing embodiments, and further including an X-ray source, a gantry, a data acquisition system, and an image reconstruction system. The X-ray source generates X-ray radiation, the gantry supports the X-ray source and the photon-counting detector, and enables them to rotate around the object being inspected. The data acquisition system acquires data output from the photon-counting detector, and the image reconstruction system reconstructs CT images based on the acquired data.

[0065] In practical applications, the working process of a CT imaging system is as follows: First, the X-ray source is turned on to generate X-ray radiation; after the X-ray radiation passes through the object being inspected, it is detected by a photon counting detector, which converts the X-ray signal into an electrical signal and processes it through a signal processing chip; the processed data is acquired by the data acquisition system and transmitted to the image reconstruction system; the image reconstruction system reconstructs the CT image based on the acquired data and displays it on a monitor for doctors to diagnose or industrial inspection personnel to analyze.

[0066] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0067] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A photon counting detector, characterized in that, The photon counting detector includes: The detection medium (11) includes multiple pixels, each of which is used to convert incident X-ray radiation into an electrical signal; A signal processing chip (12) is used to process the electrical signal; The conductive layer (13) is connected at one end to the pixel of the detection medium (11) and at the other end to the pin of the signal processing chip (12). The conductive layer (13) is a flexible conductive layer.

2. The detector according to claim 1, characterized in that, The conductive layer (13) is composed of organic flexible material and conductive filler, and the conductive layer (13) is a flexible conductive ball or anisotropic conductive film.

3. The detector according to claim 2, characterized in that, The flexible conductive sphere includes a metal layer (22) and an insulating sphere (21). The metal layer (22) is a conductive filler, and the insulating sphere (21) is a polymer organic flexible material. The metal layer (22) covers the outer surface of the insulating sphere (21).

4. The detector according to claim 2, characterized in that, The anisotropic conductive film includes an insulating layer (31) and a conductive medium (32); the insulating layer (31) is a flexible polymer organic material, and the conductive medium (32) is formed by bonding multiple conductive particles or by combining multiple conductive metal wires; the conductive medium (32) is embedded in the insulating layer (31).

5. The detector according to claim 4, characterized in that, The conductive medium (32) has two ends protruding from the insulating layer (31). One end of the conductive medium (32) is soldered to the pixel of the detection medium (11), and the other end is soldered to the pin of the signal processing chip (12).

6. The detector according to claim 2, characterized in that, The diameter of the flexible conductive ball is less than or equal to the width of a pixel in the detection medium (11).

7. The detector according to claim 4, characterized in that, The width of the conductive medium (32) is less than or equal to the width of the pixel of the probe medium (11).

8. A photon counting detector, characterized in that, include: The detection medium (11) includes multiple pixels configured to convert incident X-ray radiation into electrical signals; The signal processing chip (12) includes multiple processing units, each of which corresponds to one pixel. The processing unit is connected to the pixel via a flexible conductive layer material or an elastic conductive material.

9. The detector according to claim 8, characterized in that, The processing unit is connected to the pixel via a flexible conductive layer material, which includes an organic flexible material and a metal layer covering the organic flexible material; or... The processing unit is connected to the pixel via a flexible conductive layer material, which includes an organic flexible material and conductive particles embedded in the organic flexible material.

10. A CT imaging system, characterized in that, include: The photon counting detector as described in any one of claims 1-9.

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