Three-dimensional semiconductor pixel detector and manufacturing method thereof

Abstract

The invention relates to a three-dimensional semiconductor pixel detector and a manufacturing method thereof. A pre-prepared array carrier provided with a plurality of detection cavities arranged in an array is obtained, the inner surfaces of the detection cavities are provided with conductive layers, each detection cavity is internally provided with a central electrode of a detection pixel, the central electrodes are not in contact with the inner surfaces of the detection cavities, and the conductive layers are used as surface electrodes of the detection pixels; preparing a detection medium of a detection pixel in each detection cavity of the array carrier by adopting a preset low-temperature growth mode to obtain a three-dimensional semiconductor pixel detector comprising the array carrier and the detection pixel in each detection cavity; a detection medium in the detection cavity is located between the central electrode and the conductive layer; in each detection cavity, the detection medium surrounds the central electrode, and the surface electrode surrounds the detection medium. And the collection time of carriers can be greatly shortened, so that the saturation counting rate, the energy resolution and other performances are improved, the process is simple, the cost is low, and the applicable material range is wider.

Description

Three-dimensional semiconductor pixel detector and its manufacturing method Technical Field

[0001] This disclosure relates to the field of semiconductor technology, and in particular to a three-dimensional semiconductor pixel detector and a method for manufacturing the same. Background Technology

[0002] In radiation detection and imaging systems, detectors typically consist of a two-dimensional array of detection units or pixels, each pixel including sensor material and corresponding signal processing circuitry. During detection, incident rays or particles interact with the sensor and are converted into electrical signals, either directly (using semiconductors) or indirectly (using scintillators). The signal processing circuitry then converts these electrical signals into voltage signals and performs amplification and digitization. Each pixel detects the physical information of the rays or particles incident on its respective region, including energy and intensity. The radiation distribution measured by different pixels ultimately forms an image. The size of the detection unit or pixel is crucial to image resolution. Semiconductor detectors, achieved through microfabrication processes, can realize pixel sizes of hundreds or even tens of micrometers to achieve high-resolution radiation imaging; these detectors are also known as semiconductor pixel detectors. However, semiconductor pixel detectors suffer from limitations such as size constraints, significant signal loss, and high manufacturing costs. Summary of the Invention

[0003] In view of this, the present disclosure proposes a three-dimensional semiconductor pixel detector and a method for manufacturing the same.

[0004] According to one aspect of this disclosure, a method for manufacturing a three-dimensional semiconductor pixel detector is provided, comprising:

[0005] A pre-prepared array carrier is obtained, wherein a plurality of detection cavities are arranged in an array, a conductive layer is disposed on the inner surface of the detection cavity, and a central electrode of a detection pixel is disposed in each detection cavity. The central electrode is not in contact with the inner surface of the detection cavity, and the conductive layer is used as the surface electrode of the detection pixel.

[0006] The detection medium of the detection pixel is prepared in each of the detection cavities of the array carrier using a preset low-temperature growth method to obtain a three-dimensional semiconductor pixel detector, which includes the array carrier and the detection pixel in each of the detection cavities;

[0007] In the detection cavity, the detection medium is located between the central electrode and the conductive layer; in each detection cavity, the detection medium surrounds the central electrode, and the surface electrode surrounds the detection medium.

[0008] Each of the central electrodes is columnar and the length of the central electrode is greater than the width of the cross-section of the central electrode;

[0009] The array carrier is made of insulating material, and the detection medium is made of semiconductor material.

[0010] In one possible implementation, the shape of the detection cavity includes at least one of the following: cylindrical, prismatic, spherical, or ellipsoidal; and / or

[0011] The cross-sectional shape of the detection cavity includes at least one of the following: circular, polygonal, or polygonal with rounded corners.

[0012] In one possible implementation, the central electrode is a conductive pillar, and the material of the conductive pillar is a conductive material.

[0013] In one possible implementation, the central electrode comprises an insulating pillar and a layer of conductive material covering the side or a top surface of the insulating pillar.

[0014] In one possible implementation, when the probe cavity is cylindrical or prismatic in shape and the central electrode comprises an insulating pillar and a conductive material layer covering the sides of the insulating pillar, the array carrier is fabricated, comprising:

[0015] An insulating material layer and a first photoresist are sequentially prepared on a substrate, and the first photoresist is patterned based on a first photomask to obtain a first shielding layer. The pattern of the first shielding layer matches the plurality of center electrodes to be prepared. The first annular region in the insulating material layer corresponding to each of the center electrodes is not covered by the first shielding layer. The center of the first annular region is the same as the cross-sectional center of the center electrode, and the inner diameter of the first annular region is equal to the cross-sectional diameter of the insulating column of the center electrode to be prepared, and the outer diameter of the first annular region is greater than the cross-sectional diameter of the insulating column of the center electrode to be prepared.

[0016] Under the shielding of the first shielding layer, ion implantation is performed on the insulating material layer to implant ions into each of the first annular regions, and then the first shielding layer is removed.

[0017] By selectively etching the first annular region, insulating pillars of multiple central electrodes and a first annular space surrounding each of the central electrodes are obtained.

[0018] A conductive material layer is prepared on the side of each of the insulating pillars to obtain multiple central electrodes, and each of the first annular spaces is filled with a filling medium.

[0019] A second photoresist is prepared on top of the insulating material layer, and the second photoresist is patterned based on the second photomask to obtain a second shielding layer; the pattern of the first shielding layer matches the plurality of detector cavities to be prepared, the second annular region in the insulating material layer corresponding to each detector cavity is not covered by the second shielding layer, the center of the second annular region is the same as the cross-sectional center of the detector cavity, the outer diameter of the second annular region is equal to the cross-sectional diameter of the detector cavity to be prepared, and the inner diameter of the second annular region is greater than the cross-sectional diameter of the central electrode to be prepared;

[0020] Under the shielding of the second shielding layer, ion implantation is performed on the insulating material layer to implant ions into each of the second annular regions, and then the second shielding layer is removed.

[0021] The second annular region is etched by selective etching to obtain a plurality of second annular spaces surrounding the central electrode, and each second annular space is filled with conductive material as a surface electrode.

[0022] A third photoresist is prepared on the insulating material layer, and the third photoresist is patterned based on the third photomask to obtain a patterned photoresist. The filling medium in each of the first annular spaces is removed using the patterned photoresist as a mask, and then the patterned photoresist and the substrate are removed to obtain the array carrier.

[0023] In one possible implementation, when the shape of the detection cavity is any one of cylindrical, prismatic, spherical, or ellipsoidal, the array carrier is prepared by:

[0024] The array carrier was prepared using 3D printing.

[0025] In one possible implementation, the semiconductor material includes at least one of the following: cadmium telluride, cadmium zinc telluride, gallium arsenide, and perovskite.

[0026] In one possible implementation, the preset low-temperature growth method includes at least one of the following: solution method, CVD, PVD, and 3D printing.

[0027] In one possible implementation, the width of the cross-section of the probe cavity is 2 to 20 times the width of the cross-section of the central electrode; and / or

[0028] The height of the central electrode is 2 to 100 times the width of the cross-section of the central electrode.

[0029] According to another aspect of this disclosure, a three-dimensional semiconductor pixel detector is provided, manufactured using the above method, comprising: an array carrier, a plurality of detector pixels, each of the detector pixels including a central electrode, a detector medium, and a surface electrode;

[0030] An array carrier is provided with multiple detection cavities arranged in an array, each of which is used to carry a corresponding detection pixel;

[0031] Each of the detection cavities is provided with a central electrode of the detection pixel, and the inner surface of the detection cavity is provided with a surface electrode of the detection pixel, with the detection medium disposed between the surface electrode and the central electrode; in each of the detection cavities, the detection medium surrounds the central electrode and the surface electrode surrounds the detection medium;

[0032] Each of the central electrodes is columnar and the height of the central electrode is greater than the width of the cross-section of the central electrode;

[0033] The array carrier is made of insulating material, and the detection medium is made of semiconductor material.

[0034] The present disclosure provides a three-dimensional semiconductor pixel detector and its manufacturing method. A pre-prepared array carrier is obtained, in which multiple detector cavities are arranged in an array. A conductive layer is disposed on the inner surface of each detector cavity, and a central electrode of a detector pixel is disposed in each detector cavity. The central electrode is not in contact with the inner surface of the detector cavity, and the conductive layer serves as the surface electrode of the detector pixel. A detection medium for the detector pixel is prepared in each detector cavity of the array carrier using a preset low-temperature growth method, resulting in a three-dimensional semiconductor pixel detector. The three-dimensional semiconductor pixel detector includes the array carrier and the detector pixel located in each detector cavity. The detection medium in each detector cavity is located between the central electrode and the conductive layer. In each detector cavity, the detection medium surrounds the central electrode, and the surface electrode surrounds the detection medium. Each central electrode is columnar, and the length of the central electrode is greater than the width of its cross-section. The array carrier is made of an insulating material, and the detection medium is made of a semiconductor material. This method is applicable to detector medium materials with high resistivity and capable of low-temperature growth. By using a three-dimensional pixel electrode structure, the carrier collection time in a three-dimensional semiconductor pixel detector can be significantly reduced, thereby improving the saturation count rate and energy resolution of the detector. Compared with existing deep trench etching methods, this method is simpler, lower in cost, and applicable to a wider range of materials.

[0035] Other features and aspects of this disclosure will become clear from the following detailed description of exemplary embodiments with reference to the accompanying drawings. Attached Figure Description

[0036] The accompanying drawings, which are included in and form part of this specification, illustrate exemplary embodiments, features, and aspects of this disclosure together with the specification and serve to explain the principles of this disclosure.

[0037] Figures 1 and 2 show schematic diagrams of the structure of semiconductor pixel detectors in related technologies.

[0038] Figure 3 shows a flowchart of a method for manufacturing a three-dimensional semiconductor pixel detector according to an embodiment of the present disclosure.

[0039] Figure 4 shows a schematic diagram of the structure of a three-dimensional semiconductor pixel detector according to an embodiment of the present disclosure.

[0040] Figure 5 shows a schematic cross-sectional view of a detector pixel in a three-dimensional semiconductor pixel detector according to an embodiment of the present disclosure.

[0041] Figure 6 shows a schematic diagram of the structure of the central electrode in a three-dimensional semiconductor pixel detector according to an embodiment of the present disclosure.

[0042] Figures 7 and 8 show schematic diagrams illustrating the fabrication process of an array carrier in a three-dimensional semiconductor pixel detector according to an embodiment of the present disclosure.

[0043] Figure 9 shows a schematic flowchart of step S102 in a method for manufacturing a three-dimensional semiconductor pixel detector according to an embodiment of the present disclosure.

[0044] Figures 10-12 show schematic diagrams of the preparation of the probe medium in a method for manufacturing a three-dimensional semiconductor pixel detector according to an embodiment of the present disclosure. Detailed Implementation

[0045] Various exemplary embodiments, features, and aspects of this disclosure will now be described in detail with reference to the accompanying drawings. The same reference numerals in the drawings denote elements that have the same or similar functions. Although various aspects of the embodiments are shown in the drawings, they are not necessarily drawn to scale unless specifically indicated otherwise.

[0046] As used herein, the terms “comprising,” “including,” “having,” or variations thereof are open-ended and include one or more of the stated features, integrals, elements, steps, components, or functions, but do not exclude the presence or addition of one or more other features, integrals, elements, steps, components, functions, or groups thereof.

[0047] When an element is referred to as “connected,” “coupled,” “responding,” or a variation thereof relative to another element, it may be directly connected, coupled, or responding to another element, or there may be an intermediate element present.

[0048] Although the terms first, second, third, etc., may be used herein to describe various elements / operations, these elements / operations should not be limited by these terms. These terms are only used to distinguish one element / operation from another. Therefore, without departing from the teachings of the inventive concept, a first element / operation in some embodiments may be referred to as a second element / operation in other embodiments.

[0049] The term “exemplary” as used herein means “serving as an example, embodiment, or illustration.” Any embodiment illustrated herein as “exemplary” is not necessarily to be construed as superior to or better than other embodiments.

[0050] Furthermore, to better illustrate this disclosure, numerous specific details are set forth in the following detailed description. Those skilled in the art will understand that this disclosure can be practiced without certain specific details. In some instances, methods, means, components, and circuits well known to those skilled in the art have not been described in detail in order to highlight the main points of this disclosure.

[0051] It should be noted that the information (including but not limited to user device information, user personal information, etc.), data (including but not limited to data used for analysis, data stored, data displayed, etc.) and signals involved in this application are all authorized by the user or fully authorized by all parties, and the collection, use and processing of related data must comply with the relevant laws, regulations and standards of the relevant regions.

[0052] In related technologies, a semiconductor pixel detector includes at least two electrodes: a cathode and an anode. A bias voltage is typically applied to the electrodes to create a drift electric field. Electron-hole pairs (charge carrier pairs) generated by radiation or particles drift towards the anode and cathode respectively under the influence of the drift electric field until they are collected. During the carrier drift process, a current signal is induced on the electrodes.

[0053] To achieve signal independence between detection units, semiconductor pixel detectors are typically implemented using a two-dimensional planar array. As shown in Figure 1, for semiconductor materials with high resistivity, only one electrode, such as the anode, needs to be divided into a two-dimensional array. However, for semiconductor materials with low resistivity, such as silicon, as shown in Figure 2, doping is required to form a pn junction in the two-dimensional array to achieve signal isolation between detection units. In detectors with two-dimensional planar electrodes, electrons and holes are collected along the thickness of the detector. When detecting high-energy X / γ rays, the detector often requires a certain thickness. As the detector thickness increases, the maximum drift distance of charge carriers increases, and the collection time also increases. In high-count-rate radiation applications, such as X-ray CT imaging, the carrier collection time often limits the detector's saturation count rate. Furthermore, for compound semiconductors such as cadmium telluride, the carrier lifetime is usually short due to defects in the material. During drift, carriers are trapped by defects, causing signal loss. Therefore, the longer the carrier collection distance, the greater the signal loss, and additional fluctuations are introduced, leading to a decrease in energy resolution.

[0054] To reduce the collection distance and time of charge carriers, a three-dimensional silicon pixel detector electrode structure has been proposed, as shown in Figure 3. Each pixel electrode is a cylindrical structure penetrating deep into the silicon substrate. After charge carriers are generated, they are collected by adjacent electrodes, and the collection distance is no longer determined by the detector thickness, but only by the pixel size. However, this type of three-dimensional silicon pixel detector often requires deep reactive ion etching (DRIE), which involves expensive equipment and complex processes, with a maximum depth on the order of hundreds of micrometers. Furthermore, three-dimensional pixel detector structures manufactured using this method can only be implemented on silicon-based semiconductor materials, limiting their applicability.

[0055] To address the aforementioned technical problems, this disclosure provides a three-dimensional semiconductor pixel detector and its manufacturing method. A pre-prepared array carrier is obtained, in which multiple detector cavities are arranged in an array. A conductive layer is disposed on the inner surface of each detector cavity, and a central electrode for a detector pixel is disposed in each detector cavity. The central electrode is not in contact with the inner surface of the detector cavity, and the conductive layer serves as the surface electrode of the detector pixel. A detection medium for the detector pixel is prepared in each detector cavity of the array carrier using a preset low-temperature growth method, resulting in a three-dimensional semiconductor pixel detector. The three-dimensional semiconductor pixel detector includes the array carrier and the detector pixel located in each detector cavity. The detection medium in each detector cavity is located between the central electrode and the conductive layer. In each detector cavity, the detection medium surrounds the central electrode, and the surface electrode surrounds the detection medium. Each central electrode is columnar, and its length is greater than the width of its cross-section. The array carrier is made of an insulating material, and the detection medium is made of a semiconductor material. This method is applicable to detector medium materials with high resistivity and capable of low-temperature growth. By using a three-dimensional pixel electrode structure, the carrier collection time in a three-dimensional semiconductor pixel detector can be significantly reduced, thereby improving the saturation count rate and energy resolution of the detector. Compared with existing deep trench etching methods, this method is simpler, lower in cost, and applicable to a wider range of materials.

[0056] As shown in Figure 3, the manufacturing method of the three-dimensional semiconductor pixel detector provided in this embodiment includes steps S101 and S102. This method can manufacture the three-dimensional semiconductor pixel detector shown in Figure 4.

[0057] As shown in Figure 3, in step S101, a pre-prepared array carrier is obtained. The array carrier is provided with multiple detection cavities arranged in an array. A conductive layer is provided on the inner surface of the detection cavity, and a central electrode of the detection pixel is provided in each detection cavity. The central electrode does not contact the inner surface of the detection cavity, and the conductive layer is used as the surface electrode of the detection pixel.

[0058] In one possible implementation, the shape of the detection cavity can be a three-dimensional shape such as a cylinder, prism, sphere, or ellipsoid, and this disclosure does not limit this.

[0059] In one possible implementation, as shown in FIG5, the shape of the cross-section of the detection cavity may include at least one of the following: a circle, a polygon, a polygon with rounded corners, etc., and this disclosure does not limit it.

[0060] In one possible implementation, as shown in Figure 6, the central electrode can be a conductive pillar, and the material of the conductive pillar is a conductive material. The central electrode may include an insulating pillar and a conductive material layer covering the side or top surface of the insulating pillar. When the central electrode includes an insulating pillar and a conductive material layer covering the top surface of the insulating pillar, the thickness of the conductive material layer can be 30%-60% of the total height of the central electrode. For example, as shown in Figure 6, the thickness of the conductive material layer is 50% of the total height of the central electrode, meaning the height of the insulating pillar and the thickness of the conductive material layer are the same, each accounting for half of the height of the central electrode.

[0061] In one possible implementation, where the probe cavity is cylindrical or prismatic in shape and the central electrode comprises an insulating pillar and a conductive material layer covering the sides of the insulating pillar, as shown in Figures 7 and 8, the fabrication of the array carrier may include:

[0062] As shown in Figure 7, an insulating material layer and a first photoresist are sequentially fabricated on a substrate, and the first photoresist is patterned based on a first photomask to obtain a first masking layer. As shown in Figure 7, the pattern of the first masking layer matches the multiple center electrodes to be fabricated. The first annular region in the insulating material layer corresponding to each of the center electrodes is not covered by the first masking layer. The center of the first annular region is the same as the cross-sectional center of the center electrode, and the inner diameter of the first annular region is equal to the cross-sectional diameter of the insulating pillar of the center electrode to be fabricated, while the outer diameter of the first annular region is larger than the cross-sectional diameter of the insulating pillar of the center electrode to be fabricated.

[0063] Then, as shown in Figure 7, under the shielding of the first shielding layer, ion implantation is performed on the insulating material layer to implant ions into each of the first annular regions, and then the first shielding layer is removed. Ion implantation achieves a preset etching ratio (e.g., 2-10) between the first annular regions and other regions of the insulating material layer. As shown in Figure 7, selective etching can then be used to etch the first annular regions, obtaining multiple insulating pillars of central electrodes and a first annular space surrounding each of the central electrodes. Next, as shown in Figure 7, a conductive material layer is fabricated on the sides of each insulating pillar to obtain multiple central electrodes, and each of the first annular spaces is filled with a filling medium. This filling medium needs to be configured based on the material of the insulating material layer so that its selective etching ratio with the insulating material layer and the central electrodes reaches a preset value (e.g., 2-10).

[0064] Next, as shown in Figure 8, a second photoresist is prepared on top of the insulating material layer, and the second photoresist is patterned based on the second photomask to obtain a second shielding layer. The pattern of the first shielding layer matches the plurality of probe cavities to be prepared. The second annular region in the insulating material layer corresponding to each probe cavity is not covered by the second shielding layer. The center of the second annular region is the same as the cross-sectional center of the probe cavity, and the outer diameter of the second annular region is equal to the cross-sectional diameter of the probe cavity to be prepared, while the inner diameter of the second annular region is larger than the cross-sectional diameter of the central electrode to be prepared.

[0065] Then, as shown in Figure 8, under the shielding of the second shielding layer, ion implantation is performed on the insulating material layer to implant ions into each of the second annular regions, and then the second shielding layer is removed. Ion implantation achieves a selective etching ratio between the second annular regions and other regions of the insulating material layer that reaches a preset value (e.g., 2-10). Then, as shown in Figure 8, selective etching can be used to etch the second annular regions to obtain multiple second annular spaces surrounding the central electrode, and each second annular space is filled with conductive material as a surface electrode.

[0066] Finally, as shown in Figure 8, a third photoresist (not shown) is prepared on the insulating material layer, and the third photoresist is patterned based on the third photomask to obtain a patterned photoresist (not shown). The patterned photoresist is then used as a mask to remove the filling medium in each of the first annular spaces. The patterned photoresist is then removed, and the substrate (not shown) is then removed to obtain the array carrier.

[0067] In one possible implementation, when the shape of the detection cavity is any one of cylindrical, prismatic, spherical, or ellipsoidal, the preparation of the array carrier may include: preparing the array carrier by three-dimensional printing.

[0068] As shown in Figures 3 and 9, in step S102, the detection medium of the detection pixel is prepared in each of the detection cavities of the array carrier using a preset low-temperature growth method to obtain a three-dimensional semiconductor pixel detector. The three-dimensional semiconductor pixel detector includes the array carrier and the detection pixel in each of the detection cavities.

[0069] In the detection cavity, the detection medium is located between the central electrode and the conductive layer; in each detection cavity, the detection medium surrounds the central electrode, and the surface electrode surrounds the detection medium.

[0070] Each of the central electrodes is columnar and its length is greater than the width of its cross-section.

[0071] The array carrier is made of an insulating material, and the detection medium is made of a semiconductor material. In some embodiments, the semiconductor material used in the detection medium may include cadmium telluride, cadmium zinc telluride, gallium arsenide, perovskite, etc., and this disclosure does not limit this.

[0072] In one possible implementation, the width of the cross-section of the probe cavity is 5 to 20 times the width of the cross-section of the central electrode; in some embodiments, the width of the cross-section of the probe cavity may further be 2 to 20 times the width of the cross-section of the central electrode, for example, it can be 2 times, 3 times, 5 times, etc.

[0073] In one possible implementation, the height of the central electrode is 2 to 100 times the width of the cross-section of the central electrode. In some embodiments, the height of the central electrode is 2 to 20 times the width of the cross-section of the central electrode. For example, it can be 2 times, 3 times, 5 times, 10 times, etc.

[0074] In one possible implementation, the preset low-temperature growth method may include at least one of the following: solution method, CVD (Chemical Vapor Deposition), PVD (Physical Vapor Deposition), or 3D printing.

[0075] As shown in Figure 10, in the solution method, the array carrier can be placed in a semiconductor material solution. After confirming that the semiconductor material solution has completely immersed each detection cavity of the array carrier, the temperature of the semiconductor material solution is controlled by a temperature control device to allow the semiconductor material to precipitate at a low temperature and grow semiconductor crystals in each detection cavity, thus obtaining the detection medium.

[0076] As shown in Figure 11, in PVD, semiconductor materials are placed on a heating base and heated by electricity to evaporate them into a vacuum chamber controlled by a vacuum pump. The semiconductor materials evaporated in the vacuum chamber then move to the array carrier. The temperature of the array carrier is controlled by a temperature control base, and semiconductor materials can be deposited in each detection chamber to obtain the detection medium.

[0077] As shown in Figure 12, in 3D printing, the semiconductor solution is vaporized and then printed into crystals or thin films in each probe cavity through 3D printing nozzles to form the probe medium. Alternatively, a laser is used to ionize a semiconductor target material into a high-temperature plasma plume, which is then directed through a 3D printing nozzle in a vacuum environment to an array carrier at a low temperature under temperature control. The plume rapidly cools and solidifies instantaneously in the probe cavity to form the probe medium.

[0078] It should be noted that although the above embodiments have been used as examples to illustrate the three-dimensional semiconductor pixel detector and its manufacturing method, those skilled in the art will understand that this disclosure is not limited thereto. In fact, users can flexibly set the steps and device structure according to their personal preferences and / or actual application scenarios, as long as they conform to the technical solutions of this disclosure.

[0079] The various embodiments of this disclosure have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or technical improvements to the embodiments in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A method for manufacturing a three-dimensional semiconductor pixel detector, characterized in that, include: A pre-prepared array carrier is obtained, wherein a plurality of detection cavities are arranged in an array, a conductive layer is disposed on the inner surface of the detection cavity, and a central electrode of a detection pixel is disposed in each detection cavity. The central electrode is not in contact with the inner surface of the detection cavity, and the conductive layer is used as the surface electrode of the detection pixel. A detection medium for the detection pixel is prepared in each detection cavity of the array carrier using a preset low-temperature growth method to obtain a three-dimensional semiconductor pixel detector. The three-dimensional semiconductor pixel detector includes the array carrier and the detection pixel located in each detection cavity. The detection medium in each detection cavity is located between the central electrode and the conductive layer. In each detection cavity, the detection medium surrounds the central electrode, and the surface electrode surrounds the detection medium. Each central electrode is columnar, and the length of the central electrode is greater than the width of its cross-section. The array carrier is made of an insulating material, and the detection medium is made of a semiconductor material.

2. The method according to claim 1, characterized in that, The shape of the detection cavity includes at least one of the following: cylindrical, prismatic, spherical, ellipsoidal; and / or the shape of the cross section of the detection cavity includes at least one of the following: circular, polygonal, polygonal with rounded corners.

3. The method according to claim 1 or 2, characterized in that, The central electrode is a conductive pillar, and the material of the conductive pillar is a conductive material.

4. The method according to claim 1 or 2, characterized in that, The central electrode includes an insulating pillar and a layer of conductive material covering the side or top surface of the insulating pillar.

5. The method according to claim 4, characterized in that, When the probe cavity is cylindrical or prismatic in shape, and the central electrode includes an insulating pillar and a conductive material layer covering the side of the insulating pillar, the array carrier is fabricated by: sequentially fabricating an insulating material layer and a first photoresist on a substrate, and patterning the first photoresist based on a first photomask to obtain a first shielding layer; the pattern of the first shielding layer matches the plurality of central electrodes to be fabricated, and a first annular region in the insulating material layer corresponding to each of the central electrodes is not covered by the first shielding layer, the center of the first annular region is the same as the cross-sectional center of the central electrode, and the first annular region... The inner diameter is equal to the cross-sectional diameter of the insulating pillar of the central electrode to be prepared, and the outer diameter of the first annular region is greater than the cross-sectional diameter of the insulating pillar of the central electrode to be prepared. Under the shielding of the first shielding layer, ion implantation is performed on the insulating material layer to implant ions into each of the first annular regions, and then the first shielding layer is removed. The first annular regions are etched by selective etching to obtain multiple insulating pillars of central electrodes and a first annular space surrounding each of the central electrodes. A conductive material layer is prepared on the side of each insulating pillar to obtain multiple central electrodes, and each of the first annular regions is filled with a filling medium. A ring-shaped space is formed; a second photoresist is prepared above the insulating material layer, and the second photoresist is patterned based on a second photomask to obtain a second shielding layer; the pattern of the first shielding layer matches the plurality of detector cavities to be prepared; the second ring-shaped region in the insulating material layer corresponding to each detector cavity is not covered by the second shielding layer; the center of the second ring-shaped region is the same as the cross-sectional center of the detector cavity, and the outer diameter of the second ring-shaped region is equal to the cross-sectional diameter of the detector cavity to be prepared, and the inner diameter of the second ring-shaped region is greater than the cross-sectional diameter of the central electrode to be prepared; under the shielding of the second shielding layer... The insulating material layer is ion implanted to implant ions into each of the second annular regions, and then the second shielding layer is removed. The second annular regions are selectively etched to obtain a plurality of second annular spaces surrounding the central electrode, and each of the second annular spaces is filled with conductive material as a surface electrode. A third photoresist is prepared on the insulating material layer, and the third photoresist is patterned based on a third photomask to obtain patterned photoresist. The filling medium in each of the first annular spaces is removed using the patterned photoresist as a mask, and then the patterned photoresist and the substrate are removed to obtain the array carrier.

6. The method according to claim 4, characterized in that, When the shape of the detection cavity is any one of cylindrical, prismatic, spherical, or ellipsoidal, the array carrier is prepared by means of: preparing the array carrier by means of three-dimensional printing.

7. The method according to claim 1 or 2, characterized in that, The semiconductor material includes at least one of the following: cadmium telluride, cadmium zinc telluride, gallium arsenide, and perovskite.

8. The method according to claim 1 or 2, characterized in that, The preset low-temperature growth method includes at least one of the following: solution method, CVD, PVD, and 3D printing.

9. The method according to claim 1, characterized in that, The width of the cross-section of the detection cavity is 2 to 20 times the width of the cross-section of the central electrode; and / or the height of the central electrode is 2 to 100 times the width of the cross-section of the central electrode.

10. A three-dimensional semiconductor pixel detector, characterized in that, Manufactured using the method described in any one of claims 1-9, comprising: an array carrier and a plurality of detection pixels, each detection pixel comprising a central electrode, a detection medium, and a surface electrode; the array carrier having a plurality of detection cavities arranged in an array, each detection cavity for carrying a corresponding detection pixel; wherein, a central electrode of the detection pixel is disposed in each detection cavity, a surface electrode of the detection pixel is disposed on the inner surface of the detection cavity, and the detection medium is disposed between the surface electrode and the central electrode; in each detection cavity, the detection medium surrounds the central electrode, and the surface electrode surrounds the detection medium; wherein, each central electrode is columnar and the height of the central electrode is greater than the width of the cross-section of the central electrode; the array carrier is made of an insulating material, and the detection medium is made of a semiconductor material.

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