X-ray detection substrate and x-ray detector

Abstract

This disclosure relates to an X-ray detection substrate and an X-ray detector. The X-ray detection substrate includes: a substrate, including at least a detection functional region; a driving circuit layer formed on the substrate, the driving circuit layer including a plurality of detection pixel circuits located in the detection functional region; a first electrode layer formed on the side of the driving circuit layer away from the substrate and located in the detection functional region, the first electrode layer including a plurality of mutually disconnected first electrodes arranged in an array, each first electrode being connected to a detection pixel circuit; a conversion material layer located in the detection functional region and covering the first electrode layer; at least one surface of the conversion material layer parallel to the thickness direction of the substrate is a first X-ray receiving surface; and a second electrode layer located in the detection functional region and covering the conversion material layer, the second electrode layer being configured to apply a reference voltage. The X-ray detection substrate of this solution has good energy spectrum detection capability and a wide range of applications.

Description

Technical Field

[0001] This disclosure relates to the field of detection technology, and more specifically, to an X-ray detection substrate and an X-ray detector. Background Technology

[0002] X-ray inspection technology is widely used in industrial non-destructive testing, container scanning, circuit board inspection, medical, security, and other fields, and has broad application prospects. However, current X-ray flat panel detectors cannot obtain X-ray information of different energies, which limits their image resolution and application range. Summary of the Invention

[0003] The purpose of this disclosure is to provide an X-ray detection substrate and an X-ray detector, thereby overcoming, at least to some extent, one or more problems caused by limitations and defects in related technologies.

[0004] The first aspect of this disclosure provides an X-ray detection substrate, comprising:

[0005] The substrate includes at least a probe functional region;

[0006] A driving circuit layer is formed on the substrate, and the driving circuit layer includes a plurality of detection pixel circuits located in the detection functional area;

[0007] A first electrode layer is formed on the side of the driving circuit layer away from the substrate and located in the detection functional area. The first electrode layer includes a plurality of mutually disconnected first electrodes arranged in an array, and each first electrode is connected to a detection pixel circuit.

[0008] A conversion material layer is located in the detection functional area and covers the first electrode layer. The conversion material layer is used to convert the received X-rays into charge carriers. At least one surface of the conversion material layer that is parallel to the thickness direction of the substrate is a first X-ray receiving surface. A plane of the conversion material layer that is perpendicular to the thickness direction of the substrate is a second X-ray receiving surface. The second X-ray receiving surface is located on the side of the conversion material layer away from the first electrode layer.

[0009] A second electrode layer is located in the detection functional area and covers the conversion material layer. The second electrode layer is configured to apply a reference voltage and is a transparent electrode layer.

[0010] In one exemplary embodiment of this disclosure,

[0011] The substrate further includes a light collimation region, which is located on the side of the detection functional region closer to the first X-ray receiving surface;

[0012] The X-ray detection substrate further includes a light collimation layer, which is located in the light collimation region.

[0013] In one exemplary embodiment of this disclosure, the light collimating layer includes at least an X-ray absorbing layer;

[0014] Wherein, in the direction perpendicular to the first X-ray receiving surface, the X-ray absorbing layer covers a portion of the first X-ray receiving surface, or the X-ray absorbing layer does not overlap with the first X-ray receiving surface.

[0015] In one exemplary embodiment of this disclosure, the first X-ray receiving surface has a first region and a second region located on the side of the first region away from the substrate;

[0016] The orthographic projection of the X-ray absorbing layer onto the first X-ray receiving surface covers the first region of the first X-ray receiving surface and does not overlap with the second region of the first X-ray receiving surface.

[0017] In one exemplary embodiment of this disclosure, the ratio between the dimension of the first region in the thickness direction of the substrate and the dimension of the first X-ray receiving surface in the thickness direction of the substrate is less than or equal to 0.1.

[0018] In one exemplary embodiment of this disclosure,

[0019] The side of the X-ray absorbing layer furthest from the substrate is closer to the substrate than the side of the first electrode layer furthest from the substrate; or

[0020] The side of the X-ray absorbing layer away from the substrate is flush with the side of the first electrode layer away from the substrate.

[0021] In one exemplary embodiment of this disclosure, a plurality of the first electrodes are arranged in an array in a row direction and a column direction, wherein the row direction and the column direction are perpendicular to each other, and the row direction is a direction perpendicular to the first X-ray receiving surface; wherein,

[0022] From the direction away from the first X-ray receiving surface, the length of each of the first electrodes in each row of the first electrodes increases sequentially; or

[0023] From the direction away from the first X-ray receiving surface, the lengths of each first electrode in each row of first electrodes are equal;

[0024] Wherein, the length of the first electrode is the dimension of the first electrode in the row direction.

[0025] In one exemplary embodiment of this disclosure, the widths of each of the first electrodes are equal, wherein the width of the first electrode is the dimension of the first electrode in the column direction.

[0026] In one exemplary embodiment of this disclosure, the material of the conversion material layer is amorphous selenium, mercuric iodide, lead iodide, bismuth iodide, or zinc cadmium telluride.

[0027] In one exemplary embodiment of this disclosure,

[0028] The detection pixel circuit includes a transistor and a storage capacitor; the transistor includes a gate and an active layer opposite to each other in the thickness direction of the substrate, and a source and a drain connected to both ends of the active layer, the drain being connected to the first electrode; the storage capacitor includes a first electrode plate and a second electrode plate opposite to each other in the thickness direction of the substrate, the first electrode plate being disposed on the same layer as the gate and disconnected from each other, the second electrode plate being disposed on the same layer as the source and the drain, and the second electrode plate being connected to the drain.

[0029] The driving circuit layer further includes a gate line, a data line, and a common signal line formed on the substrate and located in the detection functional area; the gate line is disposed on the same layer as the gate and connected; the data line is disposed on the same layer as the source and connected; and the common signal line is disposed on the same layer as the first electrode plate and connected.

[0030] In one exemplary embodiment of this disclosure, the substrate is made of glass or polyimide.

[0031] A second aspect of this disclosure provides an X-ray detector comprising a plurality of X-ray detection substrates, wherein the X-ray detection substrates are any of the X-ray detection substrates described above, the plurality of X-ray detection substrates being stacked in the thickness direction of the substrate, and the first X-ray receiving surfaces of each of the X-ray detection substrates being flush.

[0032] In one exemplary embodiment of this disclosure, in any two adjacent X-ray detector substrates, the substrate of one is adjacent to the second electrode layer of the other.

[0033] In one exemplary embodiment of this disclosure, the plurality of X-ray detection substrates are divided into multiple groups, each group including two X-ray detection substrates, wherein the second electrode layer of one of the substrates in each group is adjacent to the second electrode layer of the other.

[0034] In one exemplary embodiment of this disclosure, the distance between the conversion material layers of any two adjacent X-ray detector substrates is equal.

[0035] Other features and advantages of this disclosure will become apparent from the following detailed description, or may be learned in part from practice of this disclosure.

[0036] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0037] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure. It is obvious that the drawings described below are merely some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0038] Figures 1 to 3 Schematic diagrams of the structure of the X-ray detection substrate according to different embodiments of this disclosure are shown respectively;

[0039] Figure 4 A schematic diagram of the energy spectrum detection principle of the X-ray detection substrate according to an embodiment of the present disclosure is shown;

[0040] Figure 5 A plan view of a portion of the structure of the X-ray detector substrate according to an embodiment of the present disclosure is shown;

[0041] Figure 6 It shows Figure 5 A schematic cross-sectional view of the structure shown along the AA direction;

[0042] Figure 7 and Figure 8 Schematic diagrams of the structure of the X-ray detectors described in different embodiments of this disclosure are shown respectively;

[0043] Figure 9 and Figure 10 The following are schematic plan views of partial structures of the X-ray detection substrate according to different embodiments of the present disclosure. Detailed Implementation

[0044] The technical solutions of this disclosure will be further described in detail below through embodiments and in conjunction with the accompanying drawings. In this specification, the same or similar reference numerals indicate the same or similar components. The following description of the embodiments of this disclosure with reference to the accompanying drawings is intended to explain the overall concept of this disclosure and should not be construed as a limitation thereof.

[0045] Furthermore, in the following detailed description, numerous specific details are set forth for ease of explanation to provide a thorough understanding of the embodiments disclosed herein. However, it will be apparent that one or more embodiments may be practiced without these specific details.

[0046] Unless otherwise defined, the technical or scientific terms used in this disclosure shall have the ordinary meaning understood by one of ordinary skill in the art to which this disclosure pertains. The terms "first," "second," and similar terms used in this disclosure do not indicate any order, quantity, or importance, but are merely used to distinguish different components.

[0047] As used in this disclosure, the words “including” or “having” or similar terms mean that the element or object preceding the word covers the element or object listed after the word and its equivalents, without excluding other elements or objects.

[0048] like Figures 1 to 3 As shown, this embodiment of the present disclosure provides an X-ray detection substrate 10, which may include a substrate 101, a driving circuit layer 102, a first electrode layer, a conversion material layer 104, and a second electrode layer 105.

[0049] Specifically, the substrate 101 may include at least a detection functional region 101a; a driving circuit layer 102 may be formed on the substrate 101, and the driving circuit layer 102 may include a plurality of detection pixel circuits located in the detection functional region 101a; a first electrode layer may be formed on the side of the driving circuit layer 102 away from the substrate 101 and located in the detection functional region 101a; this first electrode layer may be a patterned structure, that is: the first electrode layer may include a plurality of mutually disconnected and arrayed first electrodes 103, each first electrode 103 It is connected to a detection pixel circuit; the conversion material layer 104 can be located in the detection functional area 101a and cover the first electrode layer, that is: the orthogonal projection of the first electrode layer on the substrate 101 is located within the orthogonal projection of the conversion material layer 104 on the substrate 101; the second electrode layer 105 can be located in the detection functional area 101a and cover the conversion material layer 104, that is: the orthogonal projection of the conversion material layer 104 on the substrate 101 is located within the orthogonal projection of the second electrode layer 105 on the substrate 101, and this second electrode layer 105 is configured to apply a reference voltage.

[0050] In embodiments of this disclosure, the conversion material layer 104 is used to convert the received X-rays into charge carriers. The electron-hole pairs contained in the charge carriers drift to the first electrode layer and the second electrode layer 105 under the action of an electric field, and are collected by the first electrode layer and the second electrode layer 105 to generate a current signal.

[0051] It should be understood that, in this embodiment, the conversion material layer 104 and the second electrode layer 105 located in the detection functional area 101a can be a single-layer structure without patterning, but this is not a limitation. The structure of the conversion material layer 104 and the second electrode layer 105 can be adjusted according to the actual situation, as long as the X-ray detection substrate 10 can achieve its detection function. In the first electrode layer, each first electrode 103 is disconnected from each other, and each first electrode 103 is connected to a corresponding detection pixel circuit, thus making each first electrode 103 equivalent to a detection point.

[0052] In the embodiments of this disclosure, at least one surface of the conversion material layer 104 parallel to the thickness direction Z of the substrate 101 can be a first X-ray receiving surface 104a. When multiple X-rays of different energies, for example, when two types of X-rays, including low-energy and high-energy X-rays, are simultaneously incident from the first X-ray receiving surface 104a parallel to the thickness direction Z of the substrate 101, the generation probability of electrons excited by the interaction of X-rays of different energies with the conversion material layer 104 at different depths has different distributions. Therefore, by applying an electric field through the first electrode layer and the second electrode layer 105 to collect the electrons generated at different depths, the incident intensity of the two types of X-rays can be deduced from the depth distribution of the generated electrons, and the energy spectrum and energy resolution can be obtained simultaneously. In other words, the X-ray detection substrate 10 of the embodiments of this disclosure can realize energy spectrum detection and obtain the energy spectrum information of the image. In the medical field, this is beneficial for the resolution of soft tissues, etc., and helps in diagnosis.

[0053] in, Figure 4 The measured values ​​shown can be the energy spectrum information detected by the X-ray detection substrate of this disclosure. From these measured values, the energy received by the X-ray detection substrate, such as... Figure 4 The information shown is related to low-energy X-rays and high-energy X-rays.

[0054] Furthermore, the plane perpendicular to the thickness direction Z of the substrate 101 in the conversion material layer 104 of this embodiment can also be a second X-ray receiving surface. When using the second X-ray receiving surface perpendicular to the thickness direction Z of the substrate 101, the X-ray detection substrate 10 can also be used as a conventional flat panel detector. It should be understood that the conventional flat panel detector mentioned here refers to an X-ray detector that cannot perform energy spectrum detection. It should be noted that the first X-ray receiving surface 104a mentioned later is mainly a surface parallel to the thickness direction Z of the substrate 101.

[0055] Based on the foregoing, the X-ray detection substrate 10 of this embodiment can be used as both a conventional flat panel detector and an energy spectrum detector, greatly expanding its application range.

[0056] Furthermore, when the X-ray detection substrate 10 of this embodiment is used as an energy spectrum detector, compared with conventional energy spectrum detectors manufactured using processes incompatible with glass substrates, such as single crystal, sapphire, and APD (avalanche photodiode), the X-ray detection substrate 10 of this embodiment can be manufactured using glass substrate processes to reduce costs.

[0057] It should be noted that the glass-based process mentioned in the embodiments of this disclosure refers to using glass as substrate 101, or using PI (polyimide layer) grown on glass as substrate 101. In other words, in the X-ray detection substrate 10 of this embodiment, the material of its substrate 101 can be glass, and the functional film layers required in the X-ray detection substrate 10 (e.g., the aforementioned driving circuit layer 102, first electrode layer, conversion material layer 104, second electrode layer 105, etc.) can be directly formed on this glass substrate. This substrate 101 is part of the X-ray detection substrate 10; but not limited thereto, the material of the substrate 101 can also be polyimide (PI). When the material of the substrate 101 is PI, the manufacturing method of this X-ray detection substrate 10 can be as follows: first, a PI material layer is grown on the glass substrate, and this PI material layer is the substrate 101 of the X-ray detection substrate 10; then, other film layers required for the X-ray detection substrate 10 are formed on this substrate 101, such as the aforementioned driving circuit layer 102, first electrode layer, conversion material layer 104, second electrode layer 105, etc.; then, the substrate 101 is peeled off from the glass substrate to form the entire X-ray detection substrate 10.

[0058] In embodiments of this disclosure, the pixel detection circuit may include transistors and storage capacitors, combined with Figure 5 and Figure 6 It is known that this transistor includes a gate 1021a and an active layer 1021b opposite to each other in the thickness direction Z of the substrate 101, and a source 1021c and a drain 1021d connected to both ends of the active layer 1021b.

[0059] For example, this transistor can be a bottom-gate type, meaning that the gate 1021a is located on the side of the active layer 1021b closest to the substrate 101. The orthogonal projection of the active layer 1021b onto the substrate 101 may overlap with the orthogonal projection of the gate 1021a onto the substrate 101. The material of the gate 1021a can be a metal or alloy such as copper (Cu), silver (Ag), aluminum (Al), molybdenum (Mo), chromium (Cr), or titanium (Ti) to shield the active layer 1021b from light, thus ensuring transistor performance. However, it is not limited to this; the transistor can also be a top-gate type, meaning that the gate 1021a is located on the side of the active layer 1021b furthest from the substrate 101, depending on the specific situation. The active layer 1021b may include amorphous silicon (a-Si), indium gallium zinc oxide (IGZO), or low-temperature polycrystalline silicon (LTPS). The source 1021c and drain 1021d are arranged in the same layer, and the source 1021c and drain 1021d can be a sandwich structure, for example, Ti (titanium), Al (aluminum), Ti (titanium) are stacked in sequence. Al is easy to oxidize, and the Ti / Al / Ti sandwich structure design can add Ti above and below Al to effectively prevent Al oxidation.

[0060] Combination Figure 5 and Figure 6 As shown, the storage capacitor may include a first electrode 1022a and a second electrode 1022b that are opposite each other in the thickness direction Z of the substrate 101, that is, the orthogonal projection of the first electrode 1022a on the substrate 101 overlaps with the orthogonal projection of the second electrode 1022b on the substrate 101; the first electrode 1022a is disposed in the same layer as the gate 1021a, and the second electrode 1022b is disposed in the same layer as the source 1021c and the drain 1021d.

[0061] It should be understood that, in this disclosure, "same layer" refers to a layer structure formed using the same film deposition process to create a specific pattern, and then using the same mask to form a single patterning process. That is, one patterning process corresponds to one mask (also called a photomask). Depending on the specific pattern, a single patterning process may include multiple exposure, development, or etching processes, and the specific pattern in the formed layer structure can be continuous or discontinuous. These specific patterns may also be at different heights or have different thicknesses. This simplifies the manufacturing process, saves manufacturing costs, and improves production efficiency.

[0062] In the embodiments of this disclosure, the first plate 1022a of the storage capacitor is disconnected from the gate 1021a of the transistor, the second plate 1022b of the storage capacitor is connected to the drain 1021d of the transistor, and the drain 1021d of the transistor is also connected to the first electrode 103.

[0063] It should be understood that the detection pixel circuit includes not only the aforementioned transistors and storage capacitors, but also other structures such as... Figure 6 As shown, when the transistor is a bottom-gate type, the detection pixel circuit may further include a gate insulating layer 1026 located between the active layer 1021b and the gate 1021a and between the first electrode plate 1022a and the second electrode plate 1022b, and also includes an interlayer dielectric layer 1027 located between the source / drain electrode 1021d and the first electrode layer. Based on this, as Figure 5 and Figure 6 As shown, the first electrode 103 can be connected to the drain 1021d of the transistor through a via structure H that penetrates the interlayer dielectric layer 1027.

[0064] It should be noted that the gate insulating layer 1026 and the interlayer dielectric layer 1027 are integral layers in the entire driving circuit layer 102. The gate insulating layer 1026 and the interlayer dielectric layer 1027 can be made of inorganic materials such as silicon oxide, silicon nitride, and silicon oxynitride.

[0065] In addition, such as Figure 5 and Figure 6 As shown, the driving circuit layer 102 may further include a gate line 1023, a data line 1024, and a common signal line 1025 formed on the substrate 101 and located in the detection functional region 101a; the gate line 1023 is disposed on the same layer as and connected to the gate 1021a of the transistor; the data line 1024 is disposed on the same layer as and connected to the source 1021c; and the common signal line 1025 is disposed on the same layer as and connected to the first electrode plate 1022a.

[0066] In the embodiments of this disclosure, the orthogonal projection of the first electrode 103 on the substrate 101 can completely cover the orthogonal projection of the transistor and storage capacitor of the detector pixel circuit connected thereto on the substrate 101, but is not limited thereto, and may also cover part of the structure of the transistor or part of the structure of the storage capacitor, depending on the specific circumstances.

[0067] For example, the first electrode 103 can be a metal or alloy such as copper (Cu), silver (Ag), aluminum (Al), molybdenum (Mo), chromium (Cr), or titanium (Ti). When the first electrode 103 covers the active layer 1021b of the transistor, the first electrode 103 can shield the active layer 1021b from light to ensure the performance of the transistor. However, it is not limited to this. The first electrode 103 can also be made of other materials, such as indium tin oxide (ITO). The first electrode 103 can also be a composite structure, such as a light-shielding metal layer and a transparent metal oxide layer located away from the substrate 101, depending on the specific situation.

[0068] In the embodiments of this disclosure, a plurality of first electrodes 103 in the first electrode layer are specifically arranged in an array along the row direction M and the column direction N, wherein the row direction M and the column direction N are perpendicular to each other, and the row direction M is perpendicular to the first X-ray receiving surface 104a. Since lower-energy X-rays are completely absorbed in the region near the first X-ray receiving surface 104a, and higher-energy X-rays are completely absorbed in the region away from the first X-ray receiving surface 104a, that is, from the direction away from the first X-ray receiving surface 104a, the energy of the completely absorbed X-rays increases. Based on this, in order to ensure that the portion corresponding to each first electrode 103 can completely absorb X-rays within the corresponding energy spectrum band, such as... Figure 9 As shown, from the direction away from the first X-ray receiving surface 104a, the length of each first electrode 103 in each row of first electrodes can be increased sequentially. That is to say, X-rays of different energy ranges will be completely absorbed within the range of different electrode lengths.

[0069] It should be noted that the design of each first electrode 103 in the first electrode layer of this embodiment is not limited to the aforementioned sequential increase in length from the direction away from the first X-ray receiving surface 104a, but can also be as follows: Figure 10 As shown, the lengths of the first electrodes 103 in each row of the first electrodes are equal in the direction away from the first X-ray receiving surface 104a, in order to reduce the design difficulty; however, it is not limited to this, and the lengths of the first electrodes 103 in each row of the first electrodes may decrease sequentially in the direction away from the first X-ray receiving surface 104a, etc., depending on the specific situation.

[0070] In the embodiments of this disclosure, the width of each first electrode 103 in the first electrode layer is equal. In addition, the thickness of each first electrode 103 in the first electrode layer may be equal, but is not limited thereto. The width and thickness of each first electrode 103 may also be unequal, depending on the specific circumstances.

[0071] In addition, the spacing between two adjacent first electrodes 103 in the row direction M can be equal, and the spacing between two adjacent first electrodes 103 in the column direction N can be equal to reduce the design difficulty, but it is not limited to this and depends on the specific situation.

[0072] It should be noted that the length of the first electrode 103 mentioned in the embodiments of this disclosure is the dimension of the first electrode 103 in the row direction M, and the width of the first electrode 103 is the dimension of the first electrode 103 in the column direction N.

[0073] For example, the shape of each first electrode 103 in the first electrode layer can be as follows: Figure 9 and Figure 10The rectangular shape shown is intended to reduce design complexity, but it is not limited to this and can also be other shapes, such as elliptical or rhomboid, depending on the specific circumstances. In the embodiments of this disclosure, the conversion material layer 104 can be a direct conversion material layer. This direct conversion material layer is used to directly convert the received X-rays into charge carriers. Compared to the scheme where the conversion material layer is an indirect conversion material layer, it should be understood that the indirect conversion material layer mentioned here refers to a structure that first uses a fluorescent scintillator material to convert X-rays into visible light, and then uses a photoelectric conversion material to convert the visible light into charge carriers. Since the direct conversion material layer of this disclosure can directly convert X-rays into charge carriers, it can alleviate the loss of X-ray energy and improve the accuracy of energy spectrum detection.

[0074] For example, the material of this direct conversion material layer can be amorphous selenium (a-Se), mercuric iodide (HgI2), lead iodide (PbI2), bismuth iodide (BiI2), or cadmium zinc telluride (CZT), but is not limited to these, and can also be other materials that can convert X-rays into charge carriers.

[0075] The second electrode layer 105 can be a transparent electrode layer, for example, its material can be a transparent metal oxide material such as ITO. This design can reduce the absorption of X-rays by the second electrode layer 105 when using the second X-ray receiving surface that is perpendicular to the thickness direction Z of the substrate 101 for detection. However, it is not limited to this. The second electrode layer 105 can also be made of other metal materials, depending on the specific situation.

[0076] For example, in this embodiment of the present disclosure, when the substrate 101 is a glass substrate, the sum of the thicknesses of the substrate 101 and the driving circuit layer 102 can be 2μm to 3μm, such as 2μm, 2.2μm, 2.4μm, 2.6μm, 2.8μm, 3μm, etc.; the thicknesses of the first electrode layer and the second electrode layer 105 can be less than or equal to 1μm, such as 0.1μm, 0.3μm, 0.5μm, 0.7μm, 0.9μm, 1μm, etc. μm, etc. The thickness of the conversion material layer 104 can be from 200μm to 500μm, such as 200μm, 250μm, 300μm, 350μm, 400μm, 450μm, 500μm, etc. It should be understood that the sum of the thicknesses of the substrate 101 and the driving circuit layer 102, the thicknesses of the first electrode layer and the second electrode layer 105, and the thickness of the conversion material layer 104 are not limited to the ranges mentioned above, but depend on the specific circumstances.

[0077] In one embodiment of this disclosure, the substrate 101 may further include a light collimation region 101b, which is located on the side of the detection functional region 101a near the first X-ray receiving surface 104a (i.e., the first X-ray receiving surface 104a parallel to the thickness direction Z of the substrate 101). The light collimation region 101b is provided with a light collimation layer. That is, when X-rays are incident from the side of the first X-ray receiving surface 104a parallel to the thickness direction Z of the substrate 101, the X-rays can first pass through the light collimation region 101b and then enter the conversion material layer 104 of the detection functional region 101a.

[0078] In this embodiment of the disclosure, the stray light in the X-rays can be absorbed or corrected by using a light collimation layer, so that the X-rays entering the conversion material layer 104 are basically parallel to the substrate 101, thereby improving the energy spectrum detection accuracy and increasing the signal-to-noise ratio.

[0079] For example, this light collimating layer may include at least an X-ray absorption layer 106. In this embodiment, the light collimating layer utilizes the X-ray absorption layer 106 to absorb stray light in the X-rays, ensuring that the X-rays entering the conversion material layer 104 are substantially parallel to the substrate 101, thereby achieving light collimation. For instance, the X-ray absorption layer 106 may be a lead layer, meaning it can be made of lead, but is not limited to this; other materials can also be used, as long as they can absorb X-rays.

[0080] In the direction perpendicular to the first X-ray receiving surface 104a (i.e., the row direction M), the X-ray absorbing layer 106 may cover a portion of the first X-ray receiving surface 104a, or the X-ray absorbing layer 106 may not overlap with the first X-ray receiving surface 104a, that is, at least a portion of the first X-ray receiving surface 104a may not overlap with the X-ray absorbing layer 106.

[0081] It should be noted that the area in the first X-ray receiving surface 104a that does not overlap with the X-ray absorbing layer 106 is the main X-ray receiving area. If there is an area in the first X-ray receiving surface 104a that overlaps with the X-ray absorbing layer 106, this overlapping area can be understood as the X-ray stray light absorption area.

[0082] In an alternative embodiment, such as Figure 2As shown, the first X-ray receiving surface 104a has a first region 104aa and a second region 104ab located on the side of the first region 104aa away from the substrate 101; wherein, the orthographic projection of the X-ray absorbing layer 106 on the first X-ray receiving surface 104a covers the first region 104aa of the first X-ray receiving surface 104a and does not overlap with the second region 104ab of the first X-ray receiving surface 104a. This design facilitates the fabrication of the X-ray absorbing layer 106 and, while ensuring good energy spectrum detection, can also effectively absorb stray light in X-rays to improve the signal-to-noise ratio.

[0083] Optionally, the ratio between the dimension of the first region 104aa in the thickness direction Z of the substrate 101 and the dimension of the first X-ray receiving surface 104a in the thickness direction Z of the substrate 101 is less than or equal to 0.1. For example, if the thickness of the conversion material layer 104 is 500 μm, that is, if the dimension of the first X-ray receiving surface 104a in the thickness direction Z of the substrate 101 is 500 μm, then the dimension of the second region 104ab in the first X-ray receiving surface 104a corresponding to the X-ray absorption layer 106 in the thickness direction Z of the substrate 101 is less than or equal to 50 μm, such as 10 μm, 20 μm, 30 μm, 40 μm, 50 μm, etc. This design ensures good energy spectrum detection while effectively absorbing stray light in X-rays to improve the signal-to-noise ratio.

[0084] In another alternative embodiment, such as Figure 3 As shown, the side of the X-ray absorbing layer 106 away from the substrate 101 is closer to the substrate 101 than the side of the first electrode layer away from the substrate 101. In other words, the side of the X-ray absorbing layer 106 away from the substrate 101 is closer to the substrate 101 than the side of the conversion material layer 104 near the substrate 101. This increases the energy spectrum detection area and effectively absorbs stray light in the X-rays, thereby improving the signal-to-noise ratio. It should be noted that in this embodiment, the distance between the X-ray absorbing layer 106 and the conversion material layer 104 in the thickness direction Z of the substrate 101 should not be too large, for example, less than 10 μm, to ensure that the X-ray absorbing layer 106 can effectively absorb stray light in the X-rays.

[0085] In yet another alternative embodiment, such as Figure 1 As shown, the side of the X-ray absorption layer 106 away from the substrate 101 is flush with the side of the first electrode layer away from the substrate 101. This design ensures good energy spectrum detection while effectively absorbing stray light in X-rays to improve the signal-to-noise ratio.

[0086] In the embodiments of this disclosure, the X-ray absorbing layer 106 can be fabricated after the functional film layers on the detection functional region 101a are fabricated. That is, after the second electrode layer 105 is fabricated, an X-ray absorbing material, such as lead material, can be coated on the light collimation region 101b to form the X-ray absorbing layer 106.

[0087] It should be noted that the collimating layer of this embodiment is not limited to using the aforementioned X-ray absorption layer 106 to absorb stray light in X-rays to achieve collimation. The collimating layer of this embodiment can also be a lens structure. This lens structure can correct stray light in X-rays to achieve collimation, that is, make X-rays with large deviations in direction basically parallel to the substrate 101 after passing through the lens structure, thereby improving the energy spectrum detection accuracy and increasing the signal-to-noise ratio.

[0088] It should also be noted that, in addition to the light collimation layer, the light collimation region 101b of the substrate 101 may also have peripheral circuit structures, depending on the specific circumstances.

[0089] Furthermore, in the embodiments of this disclosure, after the second electrode layer 105 is fabricated, an encapsulation layer covering the second electrode layer 105 can be fabricated for encapsulation and protection. However, this is not a limitation, and the encapsulation layer may not be provided.

[0090] This disclosure also provides an X-ray detector, such as... Figure 7 and Figure 8 As shown, it includes multiple X-ray detection substrates 10, which are structures described in any of the foregoing embodiments and will not be repeated here. The multiple X-ray detection substrates 10 are stacked in the thickness direction Z of the substrate 101.

[0091] In the embodiments of this disclosure, by combining multiple X-ray detection substrates 10 to form an X-ray detector, a 2D energy spectrum resolution image can be directly acquired. Compared with the scheme of acquiring 2D energy spectrum image data by scanning using a single X-ray detection substrate 10, time can be saved, thereby reducing the X-ray irradiation time. Consequently, when applied in the medical field, radiation to the human body can be reduced.

[0092] Optionally, the first X-ray receiving surfaces 104a of each X-ray detector substrate 10 are flush. This design can reduce the design difficulty of data processing while directly acquiring 2D energy spectrum resolution images.

[0093] In an alternative embodiment, combined with Figure 2 and Figure 7As shown, in any two adjacent X-ray detector substrates 10, the substrate 101 of one is adjacent to the second electrode layer 105 of the other. This design ensures that the distance between the conversion material layers 104 of any two adjacent X-ray detector substrates 10 is equal, thereby making the image data acquired by each X-ray detector substrate 10 more balanced, so as to ensure that the final energy spectrum image data can better reflect the actual situation; in addition, this design can also reduce the design difficulty.

[0094] In another alternative embodiment, combined with Figure 2 and Figure 8 As shown, multiple X-ray detection substrates 10 are divided into multiple groups, each group including two X-ray detection substrates 10, with the second electrode layer 105 of one substrate adjacent to the second electrode layer 105 of the other substrate in each group. Optionally, the distance between the conversion material layers 104 of any two adjacent X-ray detection substrates 10 is equal. To ensure that the distance between the conversion material layers 104 of any two adjacent X-ray detection substrates 10 is equal, the thickness of structures such as the substrate 101, electrode layer, or encapsulation layer can be adjusted. It should be noted that, in addition to the aforementioned X-ray detection substrates 10, the X-ray detector of this disclosure may also include other components and elements, such as a housing, circuit board, etc. Those skilled in the art can supplement these components according to the specific application requirements of the X-ray detector, which will not be elaborated here.

[0095] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the disclosure herein. This disclosure is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the appended claims.

Claims

1. An X-ray detection substrate, characterized in that, The X-ray detection substrate comprises: a substrate comprising at least a detection functional region; a driving circuit layer formed on the substrate, and the driving circuit layer comprises a plurality of detection pixel circuits located in the detection functional region; a first electrode layer formed on a side of the driving circuit layer away from the substrate and located in the detection functional region, the first electrode layer comprises a plurality of first electrodes arranged in an array and disconnected with each other, and each first electrode is connected with a detection pixel circuit; a conversion material layer located in the detection functional region and covering the first electrode layer, the conversion material layer is used for converting X-rays received thereby into carriers, at least one surface of the conversion material layer parallel to a thickness direction of the substrate is a first X-ray receiving surface, and a plane of the conversion material layer perpendicular to the thickness direction of the substrate is a second X-ray receiving surface, and the second X-ray receiving surface is located on a side of the conversion material layer away from the first electrode layer; a second electrode layer located in the detection functional region and covering the conversion material layer, and the second electrode layer is configured to be loaded with a reference voltage, and the second electrode layer is a transparent electrode layer.

2. The X-ray detection substrate according to claim 1, wherein: the substrate further comprises a light collimation region located on a side of the detection functional region close to the first X-ray receiving surface; and the X-ray detection substrate further comprises a light collimation layer located in the light collimation region.

3. The X-ray detection substrate according to claim 2, characterized in that The light collimation layer comprises at least an X-ray absorption layer. In a direction perpendicular to the first X-ray receiving surface, the X-ray absorption layer covers a partial region of the first X-ray receiving surface, or the X-ray absorption layer does not overlap with the first X-ray receiving surface.

4. The X-ray detection substrate according to claim 3, wherein: the first X-ray receiving surface has a first region and a second region located on a side of the first region away from the substrate; and a projection of the X-ray absorption layer on the first X-ray receiving surface covers the first region of the first X-ray receiving surface and does not overlap with the second region of the first X-ray receiving surface.

5. The X-ray detection substrate according to claim 4, wherein: a ratio between a size of the first region in a thickness direction of the substrate and a size of the first X-ray receiving surface in the thickness direction of the substrate is less than or equal to 0.

1.

6. The X-ray detection substrate according to claim 3, wherein: a side of the X-ray absorption layer away from the substrate is closer to the substrate than a side of the first electrode layer away from the substrate; or the side of the X-ray absorption layer away from the substrate is flush with the side of the first electrode layer away from the substrate.

7. The X-ray detection substrate of claim 1, wherein, The plurality of first electrodes are arranged in an array in a row direction and a column direction, the row direction and the column direction are perpendicular to each other, and the row direction is perpendicular to the first X-ray receiving surface; and from a direction away from the first X-ray receiving surface, lengths of the first electrodes in each row of the first electrodes increase successively; or from a direction away from the first X-ray receiving surface, lengths of the first electrodes in each row of the first electrodes decrease successively. The length of each of the first electrodes is equal in each row of the first electrodes from a direction away from the first X-ray receiving surface; The length of the first electrode is a dimension of the first electrode in the row direction.

8. The X-ray detection substrate according to claim 7, characterized in that The width of each of the first electrodes is equal, wherein the width of the first electrode is a dimension of the first electrode in the column direction.

9. The X-ray detection substrate of claim 1, wherein, The material of the conversion material layer is amorphous selenium, mercury iodide, lead iodide, bismuth iodide, or cadmium zinc telluride.

10. The X-ray detection substrate according to claim 1, wherein, The detection pixel circuit comprises a transistor and a storage capacitor; the transistor comprises a gate and an active layer opposite in a thickness direction of the substrate, and a source and a drain connected to both ends of the active layer, and the drain is connected to the first electrode; the storage capacitor comprises a first plate and a second plate opposite in the thickness direction of the substrate, the first plate is arranged in the same layer as the gate and is disconnected from each other, and the second plate is arranged in the same layer as the source and the drain, and the second plate is connected to the drain; The driving circuit layer further comprises a gate line, a data line and a common signal line formed on the substrate and located in the detection functional area; the gate line is arranged in the same layer as the gate and is connected; the data line is arranged in the same layer as the source and is connected; and the common signal line is arranged in the same layer as the first plate and is connected.

11. The X-ray detection substrate according to any one of claims 1 to 10, wherein The material of the substrate comprises glass or polyimide.

12. An X-ray detector, characterized by A plurality of X-ray detection substrates according to any one of claims 1 to 11 are stacked in a thickness direction of the substrate, and the first X-ray receiving surfaces of the X-ray detection substrates are flush.

13. The X-ray detector of claim 12, characterized in that In any two adjacent X-ray detection substrates, the substrate of one is adjacent to the second electrode layer of the other.

14. The X-ray detector of claim 13, characterized in that The plurality of X-ray detection substrates are divided into groups, each group comprising two X-ray detection substrates, and the second electrode layer of one in each group is adjacent to the second electrode layer of the other.

15. The X-ray detector of claim 14, characterized in that The distance between the conversion material layers of any two adjacent X-ray detection substrates is equal.

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