Radiation detector and method for manufacturing a radiation detector

Abstract

The purpose is to provide a radiation detector and a method for manufacturing a radiation detector. According to an embodiment, the radiation detector includes: a photodiode layer including at least one pixel; and a scintillator layer including at least one geometric body, the at least one geometric body including a scintillation material and a polymer, wherein the scintillation material is configured to convert incident ionizing radiation into non-ionizing electromagnetic radiation, and wherein the at least one geometric body is configured to direct at least a portion of the converted electromagnetic radiation to the at least one pixel. There is provided a radiation detector and a method for manufacturing a radiation detector.

Description

Technical Field

[0001] The present disclosure relates to radiation detectors, and more particularly, to radiation detectors and methods for manufacturing radiation detectors. Background Art

[0002] Scintillator-based detectors can be used to detect ionizing radiation, such as x-ray radiation, γ-radiation, α-radiation, β-radiation, and neutron radiation. A scintillator-based detector can include a scintillator layer and a photodiode layer. The scintillator layer can convert incident ionizing radiation into non-ionizing radiation, and the photodiode layer can in turn convert the non-ionizing radiation into a detectable current. Summary of the Invention

[0003] The present summary is provided to introduce some concepts that will be further described below in the detailed description. The present summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

[0004] The aim is to provide a radiation detector and a method for manufacturing a radiation detector. The foregoing aim and other aims are achieved by the features of the independent claims. Further implementations are apparent from the dependent claims, the description, and the drawings.

[0005] According to a first aspect, a radiation detector includes: a photodiode layer including at least one pixel; and a scintillator layer including at least one geometric body, the at least one geometric body including a scintillation material and a polymer, wherein the scintillation material is configured to convert incident ionizing radiation into non-ionizing electromagnetic radiation, and wherein the at least one geometric body is configured to direct at least a portion of the converted electromagnetic radiation into the at least one pixel. Since the at least one geometric body includes a polymer, 3D printing can be used to produce the at least one geometric body. This can enable the at least one geometric body to be shaped at a reduced manufacturing cost.

[0006] In an implementation of the first aspect, the at least one geometric body is configured to direct the converted electromagnetic radiation into the at least one pixel using reflections inside the at least one geometric body. With such a configuration, the at least one geometric body can achieve using total internal reflection (TIR) to enhance the guiding of the converted electromagnetic radiation into the pixel.

[0007] In a further implementation of the first aspect, the at least one geometric body further includes a reflective layer located on a surface of the at least one geometric body, the reflective layer including a material that is reflective to the converted electromagnetic radiation. With such a configuration, the at least one geometric body can be capable of directing the converted electromagnetic radiation into the pixel with improved efficiency.

[0008] In yet another implementation of the first aspect, at least one geometric body includes a first surface and a second surface opposite to the first surface, wherein the surface area of the first surface is larger than that of the second surface, and wherein the second surface is closer to the photodiode layer than the first surface. With such a configuration, at least one geometric body can, for example, increase the effective surface area of each pixel.

[0009] In yet another implementation of the first aspect, at least one geometric body includes a first surface and a second surface, wherein the first surface and / or the second surface is substantially convex. With such a configuration, at least one geometric body can use the convex surface to direct the converted electromagnetic radiation into the pixel.

[0010] In yet another implementation of the first aspect, the first surface or the second surface is in contact with the photodiode layer. With such a configuration, for example, the converted electromagnetic radiation can be effectively transferred from at least one geometric body into the pixel.

[0011] In yet another implementation of the first aspect, at least one geometric body includes a height and a width, and the ratio between the height and the width is greater than one. With such a configuration, the conversion efficiency of at least one geometric body can be improved.

[0012] In yet another implementation of the first aspect, the refractive index of at least one geometric body varies in the plane of the photodiode layer. The varying refractive index can enhance the guiding of the converted electromagnetic radiation into at least one pixel.

[0013] In yet another implementation of the first aspect, the polymer includes at least one of the following: acrylonitrile butadiene styrene; polylactic acid; polyvinyl alcohol; polyethylene terephthalate; polyethylene terephthalate copolyester; high impact polystyrene; nylon; or thermoplastic elastomer. With such a configuration, at least one geometric body can be 3D printed using a conventional 3D printing process and / or equipment.

[0014] In yet another implementation of the first aspect, at least one geometric body includes a first geometric body and a second geometric body, wherein the first geometric body includes a first scintillation material, and wherein the second geometric body includes a second scintillation material. With such a configuration, different wavelength ranges can be detected using the same detector.

[0015] In yet another implementation of the first aspect, the first scintillation material is configured to convert ionizing radiation in a first wavelength range into a first non-ionizing electromagnetic radiation, and wherein the second scintillation material is configured to convert ionizing radiation in a second wavelength range into a second non-ionizing electromagnetic radiation. With such a configuration, different wavelength ranges can be detected using the same detector.

[0016] In another implementation of the first aspect, the polymer includes a scintillating material. With such a configuration, the ionizing radiation can be converted into non-ionizing electromagnetic radiation by utilizing the scintillation characteristics of the polymer itself.

[0017] According to the second aspect, a method for manufacturing a radiation detector includes: providing a photodiode layer including at least one pixel; 3D printing a scintillator layer onto the photodiode layer using a polymer, wherein the scintillator layer includes at least one geometric body, the at least one geometric body includes a scintillating material and a polymer, wherein the scintillating material is configured to convert incident ionizing radiation into non-ionizing electromagnetic radiation, and wherein the at least one geometric body is configured to guide the converted electromagnetic radiation into at least one pixel. With such a method, the at least one geometric body can be shaped with improved accuracy and / or reduced manufacturing cost.

[0018] In one implementation of the second aspect, the method further includes adding the scintillating material to the polymer before 3D printing.

[0019] In another implementation of the second aspect, one of the following is used to perform 3D printing: stereolithography; binder jetting; fused deposition modeling; digital light processing; selective laser sintering; or laminated object manufacturing.

[0020] In another implementation of the second aspect, the at least one geometric body is configured to guide the converted electromagnetic radiation into at least one pixel using reflections inside the geometric body.

[0021] In another implementation of the second aspect, the at least one geometric body further includes a reflective layer located on the surface of the geometric body, and the reflective layer includes a material that is reflective to the converted electromagnetic radiation.

[0022] In another implementation of the second aspect, the at least one geometric body includes a first surface and a second surface opposite to the first surface, wherein the surface area of the first surface is larger than that of the second surface, and wherein the second surface is closer to the photodiode layer than the first surface.

[0023] In another implementation of the second aspect, the at least one geometric body includes a first surface and a second surface, wherein the first surface and / or the second surface is substantially convex.

[0024] In another implementation of the second aspect, the first surface or the second surface is in contact with the photodiode layer.

[0025] In yet another implementation of the second aspect, at least one geometric body includes a height and a width, and the ratio between the height and the width is greater than one.

[0026] In yet another implementation of the second aspect, the refractive index of at least one geometric body varies in the plane of the photodiode layer. The varying refractive index can enhance the guiding of the converted electromagnetic radiation into at least one pixel.

[0027] In yet another implementation of the second aspect, the polymer includes at least one of the following: acrylonitrile butadiene styrene; polylactic acid; polyvinyl alcohol; polyethylene terephthalate; polyethylene terephthalate copolyester; high impact polystyrene; nylon; or thermoplastic elastomer.

[0028] In yet another implementation of the second aspect, at least one geometric body includes a first geometric body and a second geometric body, wherein the first geometric body includes a first scintillating material, and wherein the second geometric body includes a second scintillating material.

[0029] In yet another implementation of the second aspect, the first scintillating material is configured to convert ionizing radiation in a first wavelength range into a first non-ionizing electromagnetic radiation, and wherein the second scintillating material is configured to convert ionizing radiation in a second wavelength range into a second non-ionizing electromagnetic radiation.

[0030] In yet another implementation of the second aspect, the polymer includes a scintillating material.

[0031] It can be understood that the implementations of the second aspect described above can be used in combination with each other. Several implementations can be combined together to form additional implementations.

[0032] Many accompanying features will be more easily understood, because these accompanying features become better understood by referring to the following detailed description considered in conjunction with the drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Hereinafter, example embodiments are described in more detail with reference to the drawings, in which:

[0034] Figure 1 A schematic representation of a cross-sectional view of a radiation detector according to an embodiment is shown;

[0035] Figure 2 A schematic representation of a perspective view of a radiation detector according to an embodiment is shown;

[0036] Figure 3 A schematic representation of a perspective view of a radiation detector according to an embodiment is shown;

[0037] Figure 4Shows a schematic representation of a cross-sectional view of a radiation detector according to an embodiment;

[0038] Figure 5 Shows a schematic representation of a perspective view of a radiation detector according to an embodiment;

[0039] Figure 6 Shows a schematic representation of a cross-sectional view of a radiation detector according to an embodiment;

[0040] Figure 7a Shows a schematic representation of a cross-sectional view of a radiation detector according to an embodiment;

[0041] Figure 7b Shows a schematic representation of a cross-sectional view of a radiation detector according to another embodiment;

[0042] Figure 8 Shows a schematic representation of a perspective view of a radiation detector according to an embodiment;

[0043] Figure 9 Shows a schematic representation of a cross-sectional view of a radiation detector according to an embodiment;

[0044] Figure 10 Shows a schematic representation of a cross-sectional view of a radiation detector according to an embodiment; and

[0045] Figure 11 Shows a flowchart representation of a method for manufacturing a radiation detector according to an embodiment.

[0046] Hereinafter, the same reference numerals refer to the same features or at least functionally equivalent features. Detailed Description

[0047] In the following description, reference is made to the accompanying drawings, which form a part of the present disclosure, and in which specific aspects in which the present disclosure may be embodied are shown in a diagrammatic manner. It should be understood that other aspects may be utilized and structural or logical changes may be made without departing from the scope of the present disclosure. Since the scope of the present disclosure is defined by the appended claims, the following detailed description should not be construed in a limiting sense.

[0048] For example, it should be understood that the disclosure related to the described method can also be applicable to the corresponding apparatus or system configured to perform the method, and vice versa. For example, if specific method steps are described, the corresponding apparatus may include units for performing the described method steps, even if such units are not explicitly described or shown in the figures. On the other hand, for example, if a specific device is described based on functional units, the corresponding method may include steps for performing the described functions, even if such steps are not explicitly described or shown in the figures. Additionally, it should be understood that, unless otherwise specifically stated, the features of the various example aspects described herein can be combined with each other.

[0049] Figure 1 A schematic representation of a cross-sectional view of a radiation detector 100 according to an embodiment is shown.

[0050] According to an embodiment, the radiation detector 100 includes: a photodiode layer 101, which includes at least one pixel 102; and a scintillator layer 103, which includes at least one geometric body 104, and at least one geometric body 104 includes a scintillation material and a polymer. The scintillation material is configured to convert incident ionizing radiation 105 into non-ionizing electromagnetic radiation 106. The geometric body 104 is configured to direct at least a portion of the converted electromagnetic radiation 106 into at least one pixel 102.

[0051] Since at least one geometric body 104 includes a polymer, 3D printing can be used to produce at least one geometric body 104. This can enable various shapes for at least one geometric body 104, which can enhance the directing of the converted electromagnetic radiation 106 into at least one pixel 102.

[0052] According to an embodiment, at least one geometric body 104 includes a height and a width, and the ratio between the height and the width is greater than one. The ratio may refer to the height divided by the width. Thus, the height can be greater than the width. The height can be measured in a direction substantially perpendicular to the plane of the photodiode layer 101. The width can be measured substantially within the plane of the photodiode layer 101. Due to the height of at least one geometric body 104, the geometric body 104 can be capable of converting more ionizing radiation 105 into non-ionizing radiation 106. Alternatively or additionally, the ratio between the height and the width can be greater than, for example, 2, 3, 4, 5, 6, 7, 8, 9, or 10.

[0053] According to an embodiment, at least one geometric body 104 is configured to direct the converted electromagnetic radiation 106 into at least one pixel 102 using reflections inside the geometric body 104. Since the refractive index of the material of the at least one geometric body 104 can be greater than the refractive index of the surrounding material such as air, the converted electromagnetic radiation 106 can undergo one or more total internal reflections (TIR) within the geometric body 104. Thus, TIR can direct the converted electromagnetic radiation 106 into at least one pixel 102.

[0054] According to an embodiment, the polymer includes a scintillating material. The polymer itself can have scintillation properties. Alternatively or additionally, the scintillating material can be added to the polymer. Before being added to the polymer, the scintillating material can be, for example, in powder form.

[0055] As used herein, the term "ionizing radiation" can refer to, for example, x-ray radiation, γ-ray radiation, α-radiation, or β-radiation. The wavelength of the ionizing radiation 105 can be, for example, less than 1 nm. The ionizing radiation 105 can include various wavelengths.

[0056] The scintillating material can include, for example, gadolinium oxysulfide (GOS). GOS can be doped with, for example, terbium, praseodymium, and / or fluorine. Alternatively or additionally, the scintillator material can include: cesium iodide (CsI), sodium iodide (NaI), garnet, perovskite, and / or oxide scintillators such as silicates, tungstates, oxyorthosilicates.

[0057] The grain size of the scintillating material can be, for example, in the range of 10 micrometers (μm) to 200 micrometers (μm), or in any sub-range of this range, such as 10 μm to 100 μm, 50 μm to 150 μm, or 30 μm to 130 μm.

[0058] The coating weight of the scintillating material can be, for example, in the range of 40 milligrams to 500 milligrams per square centimeter (mg / cm 2 ) or in any sub-range of this range, such as 40 mg / cm 2 to 400 mg / cm 2 , 50 mg / cm 2 to 300 mg / cm 2 or 100 mg / cm 2 to 400 mg / cm 2 .

[0059] Figure 2 A schematic representation of a perspective view of a radiation detector 100 according to an embodiment is shown. Figure 2 The radiation detector 100 shown in the embodiment of Figure 1 can be similar to the radiation detector 100 shown in the embodiment of

[0060] At least one geometric body 104 may include, for example, a columnar body. Examples of such columnar bodies are shown in the Figure 1 and Figure 2 embodiments. When the ionizing radiation 105 enters the at least one geometric body 104, the scintillation material in the at least one geometric body 104 may convert the ionizing radiation 105 into non-ionizing electromagnetic radiation 106. The non-ionizing radiation 106 may have a longer wavelength than the ionizing radiation 105.

[0061] The converted electromagnetic radiation 106 may be referred to as non-ionizing radiation, converted non-ionizing radiation, non-ionizing electromagnetic radiation, converted electromagnetic radiation, converted non-ionizing radiation, or the like.

[0062] The converted electromagnetic radiation 106 may be, for example, non-ionizing electromagnetic radiation. The converted electromagnetic radiation 106 may include, for example, infrared (IR) radiation, visible light (VIS) radiation, and / or ultraviolet (UV) radiation. The wavelength of the converted electromagnetic radiation 106 may be longer than the wavelength of the ionizing radiation 105. For example, the wavelength of the converted electromagnetic radiation may be in the range of 100 micrometers (μm) to 10 nanometers (nm). The converted electromagnetic radiation 106 may include electromagnetic radiation of various wavelengths.

[0063] The height of the at least one geometric body 104 may be used to configure the conversion efficiency of the at least one geometric body 104.

[0064] Since the refractive index of the at least one geometric body 104 may be greater than the refractive index of the surrounding material, such as air, the converted electromagnetic radiation 106 may undergo reflection inside the at least one geometric body 104. Thus, at least a portion of the converted electromagnetic radiation 106 may be substantially confined within the at least one geometric body 104. Thus, the at least one geometric body 104 may guide the converted electromagnetic radiation 106 into at least one pixel 102. Therefore, the at least one geometric body 104 may be configured to act as a waveguide for the converted electromagnetic radiation 106. In this way, the at least one geometric body 104 may reduce the leakage / crosstalk of the converted electromagnetic radiation 106 between adjacent pixels 102.

[0065] Although in the Figure 1 embodiments, the cross-section of the at least one geometric body 104 in the plane of the photodiode layer 101 may be shown as circular, the cross-section of the at least one geometric body 104 may have any shape. For example, the cross-section may be rectangular, square, triangular, elliptical, or any polygon.

[0066] In some embodiments, the scintillator layer 103 may include a plurality of geometric bodies 104. In some embodiments, the scintillator layer 103 may include at least two geometric bodies 104.

[0067] At least one pixel 102 may be configured to convert the converted electromagnetic radiation 106 into a current. A voltage may be applied across the photodiode layer 101, and the electron-hole pairs generated in the pixel 102 may be detected as a current.

[0068] As can be understood by those skilled in the art, at least one pixel 102 may be implemented in various ways. For example, each pixel 102 may include an n-type semiconductor and the remainder of the photodiode layer may include a p-type semiconductor. When a voltage is applied across the pn junction, the current caused by the electron-hole pairs generated in the pn junction by the converted electromagnetic radiation may be detected. The detector 100 may also include Figure 1 and Figure 2 other components not shown in the embodiments, such as bias plates, substrates, integrated circuits, and / or the like.

[0069] Figure 3 FIG. shows a schematic representation of a perspective view of a radiation detector 100 according to an embodiment.

[0070] Figure 4 FIG. shows a schematic representation of a cross-sectional view of a radiation detector 100 according to an embodiment. Figure 4 The radiation detector 100 shown in the embodiment of may be similar to Figure 3 the radiation detector 100 shown in the embodiment of.

[0071] According to an embodiment, at least one geometric body 104 includes a first surface 107 and a second surface 108 opposite the first surface 107, wherein the surface area of the first surface 107 is larger than the surface area of the second surface 108, and wherein the second surface 108 is closer to the photodiode layer 101 than the first surface 107. The first surface 107 and / or the second surface 108 may be substantially planar / flattened.

[0072] At least one geometric body 104 may include a first surface 107 and a second surface 108. The second surface may be closer to the photodiode layer 101 than the first surface 107. The second surface 108 may be in contact with the photodiode layer 101. The surface area of the first surface 107 may be larger than the surface area of the second surface 108. The first surface 107 and / or the second surface 108 may be substantially parallel to the plane of the photodiode layer 101.

[0073] Each of at least one geometric body 104 may be substantially shaped like a square frustum. Figure 4An embodiment shows a schematic representation of a cross-section of such a geometric body 104. The cross-section may be substantially an isosceles trapezoid. Alternatively, at least one geometric body 104 may be shaped as other types of frustum.

[0074] Due to the shape of at least one geometric body 104, the scintillator layer 103 may be able to collect more ionizing radiation into at least one pixel 102. Since the scintillation material inside at least one geometric body 104 converts ionizing radiation into non-ionizing electromagnetic radiation, the side surface 109 of at least one geometric body 104 may guide the converted electromagnetic radiation into at least one pixel 102 in the photodiode layer 101. In addition, due to the larger surface area of the first surface 107, at least one geometric body 104 may collect more ionizing radiation. This may reduce the insensitive area (dead zone) between the pixels of the photodiode layer 101 and enable a pixelated photodiode with a reduced and / or even eliminated spatial insensitive area between the pixels.

[0075] Figure 5 A schematic representation of a perspective view of a radiation detector 100 according to an embodiment is shown.

[0076] Figure 6 A schematic representation of a cross-sectional view of a radiation detector 100 according to an embodiment is shown. Figure 6 The radiation detector 100 shown in the embodiment of Figure 5 may be similar to the radiation detector 100 shown in the embodiment of

[0077] According to an embodiment, at least one geometric body 104 includes a first surface 107 and a second surface 108, wherein the first surface 107 and / or the second surface 108 is substantially convex.

[0078] According to another embodiment, the first surface 107 or the second surface 108 is in contact with the photodiode layer 101.

[0079] At least one geometric body 104 may include, for example, a microlens. Examples of such microlenses are shown in the embodiments of Figure 5 and Figure 6

[0080] At least one geometric body 104 may include a substantially convex first surface 107 and a substantially flat second surface 108. The second surface 108 may be closer to the photodiode layer 101 than the first surface 107. The second surface 108 may be in contact with the photodiode layer 101. The first surface 107 and / or the second surface 108 may be substantially parallel to the plane of the photodiode layer 101.

[0081] Due to the substantially convex first surface 107, at least one geometric body 104 can be used as a plano-convex lens. When the ionizing radiation 105 is converted into non-ionizing electromagnetic radiation 106, the converted electromagnetic radiation 106 can propagate in all directions. Due to the possible refractive index difference between at least one geometric body 104 and the material surrounding the at least one geometric body 104, the first surface 107 can reflect the part of the converted electromagnetic radiation 106 that propagates out of the photodiode layer 101 back to the photodiode layer 101. Therefore, the pixels 102 in the photodiode layer 101 can be able to collect a larger part of the converted electromagnetic radiation 106.

[0082] Figure 7a A schematic representation of a cross-sectional view of a radiation detector 100 according to an embodiment is shown.

[0083] According to an embodiment, at least one geometric body 104 can include a substantially flat first surface 107 and a substantially convex second surface 108. The second surface 108 can be closer to the photodiode layer 101 than the first surface 107. The second surface 108 can be in contact with the photodiode layer 101. The first surface 107 and / or the second surface 108 can be substantially parallel to the plane of the photodiode layer 101.

[0084] Due to the convex second surface 108, at least one geometric body 104 can be used as a plano-convex lens. Therefore, the converted electromagnetic radiation 106 can be focused into at least one pixel 102 through at least one geometric body 104.

[0085] Figure 7b A schematic representation of a cross-sectional view of a radiation detector 100 according to an embodiment is shown. The gradient inside at least one geometric body 104 can correspond to the refractive index of the material.

[0086] According to an embodiment, the refractive index of at least one geometric body 104 varies in the plane of the photodiode layer 101. The refractive index can include a gradient in the plane of the photodiode layer 101. Figure 7b The embodiment is an example of such a radiation detector 100.

[0087] The refractive index of at least one geometric body 104 can vary in at least one direction in the plane of the photodiode layer 101. The refractive index can vary gradually. For example, the refractive index of the exterior of the geometric body 104 can be lower than the refractive index of the middle of the geometric body 104. The refractive index near the side surfaces of the geometric body 104 that are substantially perpendicular to the photodiode layer 101 can be lower than the refractive index of the middle of the geometric body 104. For example, if the cross-section of at least one geometric body is substantially circular in the plane of the photodiode layer 101, the refractive index can vary radially. Similar to the lens structure presented in the embodiment of Figure 7a such a varying refractive index can enhance the guiding of the converted electromagnetic radiation 106 into at least one pixel 102.

[0088] 3D printing can enable the gradual variation of the refractive index of at least one geometric body 104. This can be achieved, for example, by varying the mixing ratio of the printing raw materials.

[0089] Figure 8 A schematic representation of a perspective view of a radiation detector 100 according to an embodiment is shown.

[0090] According to an embodiment, at least one geometric body 104 further includes a reflective layer 110 located on the surface of the geometric body 104, and the reflective layer 110 includes a material that is reflective to the converted electromagnetic radiation.

[0091] According to an embodiment, at least one geometric body includes periodically or randomly positioned light guiding structures such as fibers, columns, a lower density scintillation coating, or regions having a density gradient that can be achieved by varying the mixing ratio of the printing raw materials. Compared with geometric bodies without these light guiding structures, these periodically or randomly positioned structures can increase the amount of electromagnetic radiation collected.

[0092] Figure 9 A schematic representation of a cross-sectional view of a radiation detector 100 according to an embodiment is shown. Figure 9 The radiation detector 100 shown in the embodiment of Figure 8 can be similar to the radiation detector 100 shown in the embodiment of

[0093] The scintillator layer 103 can also include a reflective layer 110. The reflective layer can be located on the surface of at least one geometric body 104. Figure 8 and Figure 9 The embodiment of

[0094] The reflective layer 110 can be reflective at the wavelength of the converted electromagnetic radiation 106. Accordingly, the reflective layer 110 can also direct the converted electromagnetic radiation 106 into the pixels 102 in the photodiode layer 101.

[0095] The reflective layer 110 can be reflective at all wavelengths of the converted electromagnetic radiation 105 or at some wavelengths of the converted electromagnetic radiation 106. The average reflectivity of the reflective layer 110 at the wavelength of the converted electromagnetic radiation 106 can be, for example, greater than 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9.

[0096] In some embodiments, the reflective layer 110 can include retroreflective material.

[0097] In some embodiments, the reflective layer 110 can include a material having a reflectivity that is less than the reflectivity of the material of the geometric body 104.

[0098] In some embodiments, each geometric body 104 can be substantially aligned with a pixel 102 in the photodiode layer 101.

[0099] Figure 10 A schematic representation of a radiation detector 100 configured for multi-energy imaging according to an embodiment is shown.

[0100] According to an embodiment, at least one geometric body includes a first geometric body 104_1 and a second geometric body 104_2, wherein the first geometric body 104_1 includes a first scintillation material, and wherein the second geometric body 104_2 includes a second scintillation material.

[0101] According to another embodiment, the first scintillation material is configured to convert ionizing radiation 105_1 in a first wavelength range into first non-ionizing electromagnetic radiation 106_1, and wherein the second scintillation material is configured to convert ionizing radiation 105_2 in a second wavelength range into second non-ionizing electromagnetic radiation 106_2.

[0102] The scintillator layer 103 can include at least one geometric body 104_1, 104_2, and at least one geometric body 104_1, 104_2 includes different scintillation materials. Accordingly, at least one geometric body 104_1, 104_2 can be configured to convert ionizing radiation in different wavelength ranges into non-ionizing electromagnetic radiation 106_1, 106_2.

[0103] The converted electromagnetic radiations 106_1, 106_2 may also include different wavelengths. For example, the first converted electromagnetic radiation 106_1 may include a UV wavelength, and the second converted electromagnetic radiation 106_2 may include a VIS wavelength, or vice versa. Alternatively or additionally, the converted electromagnetic radiations 106_1, 106_2 may include substantially the same wavelength and / or their wavelengths may overlap.

[0104] Figure 11 A flowchart representation of a method for manufacturing a radiation detector according to an embodiment is shown.

[0105] According to an embodiment, a method 1100 for manufacturing a radiation detector includes: providing 1101 a photodiode layer including at least one pixel; and 3D printing 1102 a scintillator layer onto the photodiode layer using a polymer, wherein the scintillator layer includes at least one geometric body, the at least one geometric body includes a scintillation material and a polymer, wherein the scintillation material is configured to convert incident ionizing radiation into non-ionizing electromagnetic radiation, and wherein the geometric body is configured to direct the converted electromagnetic radiation into at least one pixel.

[0106] According to an embodiment, the method 1100 for manufacturing a radiation detector further includes adding a scintillation material to the polymer before 3D printing. In some embodiments, the scintillation material may be in powder form.

[0107] Since at least one geometric body 104 can be produced on the photodiode layer 101 using 3D printing, the printing material can act as a scintillator and an adhesive. Thus, an optical glue can be omitted, and thereby an intermediate layer between the scintillator layer 103 and the photodiode layer 101 can be omitted. This can reduce the light loss between the scintillator layer 103 and the photodiode layer 101.

[0108] The price of printable raw materials can be significantly lower than the price of standard scintillators. In particular, UV-curable printing techniques may be suitable for 3D printing at least one geometric body 104. However, in principle, any 3D printing technique may be suitable. Many plastics, such as aromatic plastics like polyvinyltoluene (PVT) and polystyrene (PS), and some containing fluorescent dies such as 2,5-diphenyl oxazole (PPO) and 1,4-bis(5-phenyl The UV-curable materials of 1,4-bis(5-phenyl-1,3,4-oxadiazol-2-yl)benzene (POPOP) are natural scintillators. These materials can emit visible light or UV light when absorbing X-rays. Therefore, cheaper plastics that can be directly deposited onto the photodiode layer 101 can be used to replace expensive scintillator materials. This may be particularly useful for the photodiode layer 101 that is most sensitive in the VIS and / or UV wavelength regions.

[0109] The scintillation ability of printed plastics can be increased by adding scintillator materials to the original printing materials. If the scintillator materials are in the form of powder or solution, such as praseodymium-doped gadolinium oxysulfide (Gd2O2S:Pr), zinc selenide (ZnSe), or neutron absorbers such as boron-10 ( 10 B) and gadolinium-157 ( 157 Gd), this may be particularly simple. This method can also be used to print scintillators of various emission colors onto the same photodiode by adding different scintillator materials at different positions. This can enable multi-color X-ray or gamma-ray imaging as well as energy-specific scintillation. Therefore, a multi-energy radiation detector using a single scintillator layer and a photodiode layer is possible.

[0110] Another advantage of 3D printing the scintillator into the photodiode may lie in that the printed shape can be adjusted arbitrarily. Therefore, application-specific scintillator shapes such as having trapezoidal sidewalls or microlenses, as well as individual scintillators for each photodiode pixel, are possible. Thus, pixelated scintillators can be produced at a lower cost. For conventional scintillators, arbitrary shapes and microlenses may be impossible or infeasible, while pixelated scintillators may be more expensive due to higher production costs.

[0111] The 3D-printed scintillator can also be deposited with an increased thickness, such as several millimeters or several centimeters. This can make it possible to mitigate the possible disadvantage of the lower absorption efficiency of plastics by increasing the X-ray absorption length and thus increasing the overall efficiency of the scintillator layer 103.

[0112] For example, digital light processing (DLP), fused deposition modeling (FDM), stereolithography (SLA), binder jetting, selective laser sintering (SLS), selective laser melting (SLM), electron beam melting (EBM), and / or laminated object manufacturing (LOM) can be used to perform 3D printing 1102.

[0113] In this article, the term "3D printing" can refer to various processes of combining or curing materials under computer control to create three-dimensional objects. For example, in 3D printing, materials such as liquid molecules or powder grains can be added and these materials can be fused together. 3D printing can be performed layer by layer. 3D printing can also be referred to as three-dimensional printing or the like.

[0114] The polymer can be any polymer used in, for example, 3D printing. The polymer can be thermoplastic. The polymer can be ultraviolet curable.

[0115] The polymer can include, for example, acrylonitrile butadiene styrene (ABS), polylactic acid (PLA), polyvinyl alcohol (PVA), polyethylene terephthalate (PET), polyethylene terephthalate copolyester (PETT), high impact polystyrene (HIPS), nylon, thermoplastic elastomer (TPE), aromatic plastics such as polyvinyltoluene (PVT) and polystyrene (PS), 2,5-diphenyl oxazole (PPO) and / or 1,4-bis(5-phenyl oxazol-2-yl)benzene (POPOP).

[0116] Any range or device value given herein can be extended or varied without losing the desired effect. Additionally, unless explicitly prohibited, any embodiment can be combined with another embodiment.

[0117] Although the subject matter has been described in language specific to structural features and / or acts, it is to be understood that the subject matter defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as examples for implementing the claims, and other equivalent features and acts are intended to fall within the scope of the claims.

[0118] It should be understood that the benefits and advantages described above may relate to one embodiment, or may relate to multiple embodiments. Embodiments are not limited to embodiments that solve any or all of the stated problems or have any or all of the stated benefits and advantages. It will also be understood that references to "one" item can refer to one or more of these items.

[0119] The steps of the methods described herein can be performed in any suitable order, or simultaneously where appropriate. Additionally, individual blocks can be deleted from any method without departing from the spirit and scope of the subject matter described herein. Without losing the desired effect, aspects of any of the embodiments described above can be combined with aspects of any of the other embodiments described to form additional embodiments.

[0120] The term "comprising" is used herein to mean including the identified method, block, or element, but such block or element does not include an exclusive list, and the method or apparatus can contain additional blocks or elements.

[0121] It should be understood that the above description is given by way of example only, and various modifications can be made by those skilled in the art. The foregoing specification, examples and data provide a complete description of the structure and use of the exemplary embodiments. Although the various embodiments have been described above with a certain degree of particularity or with reference to one or more individual embodiments, those skilled in the art can make various changes to the disclosed embodiments without departing from the spirit or scope of this specification.

Claims

1. A radiation detector (100), comprising: A photodiode layer (101) comprising at least one pixel (102); And A scintillator layer (103) comprising at least one geometric body (104), the at least one geometric body (104) comprising a scintillation material and a polymer, wherein the scintillation material is configured to convert incident ionizing radiation (105) into non-ionizing electromagnetic radiation (106), and wherein the at least one geometric body (104) is configured to direct at least a portion of the converted electromagnetic radiation (106) into the at least one pixel (102) using reflections inside the at least one geometric body; Wherein the at least one geometric body (104) is further configured to direct at least a portion of the converted electromagnetic radiation (106) into the at least one pixel (102) via a refractive index of the at least one geometric body (104) that varies in a plane of the photodiode layer (101).

2. The radiation detector (100) according to claim 1, wherein, The at least one geometric body further comprises a reflective layer (110) located on a surface of the at least one geometric body, the reflective layer (110) comprising a material that is reflective of the converted electromagnetic radiation.

3. The radiation detector (100) according to claim 1 or 2, wherein, The at least one geometric body comprises a first surface (107) and a second surface (108), wherein the first surface and / or the second surface is substantially convex.

4. The radiation detector (100) according to claim 3, wherein, The first surface or the second surface is in contact with the photodiode layer (101).

5. The radiation detector (100) according to claim 1 or 2, wherein, The at least one geometric body comprises a height and a width, and a ratio between the height and the width is greater than one.

6. The radiation detector (100) according to claim 1 or 2, wherein, The at least one geometric body comprises a first surface (107) and a second surface (108) opposite the first surface, wherein a surface area of the first surface is greater than a surface area of the second surface, and wherein the second surface is closer to the photodiode layer than the first surface.

7. The radiation detector (100) according to claim 1 or 2, wherein, The polymer comprises at least one of the following: Acrylonitrile butadiene styrene; Polylactic acid; Polyvinyl alcohol; Polyethylene terephthalate; Polyethylene terephthalate copolyester; High impact polystyrene; Nylon; or Thermoplastic elastomer.

8. The radiation detector (100) according to claim 1, wherein, The at least one geometric body comprises a first geometric body (104_1) and a second geometric body (104_2), wherein the first geometric body comprises a first scintillation material, and wherein the second geometric body comprises a second scintillation material.

9. The radiation detector (100) according to claim 8, wherein, The first scintillation material is configured to convert ionizing radiation (105_1) in a first wavelength range into first non-ionizing electromagnetic radiation (106_1), and wherein the second scintillation material is configured to convert ionizing radiation (105_2) in a second wavelength range into second non-ionizing electromagnetic radiation (106_2).

10. The radiation detector (100) according to claim 1 or 2, wherein, The polymer comprises the scintillation material.

11. A method (1100) for manufacturing a radiation detector, comprising: Providing (1101) a photodiode layer comprising at least one pixel; And 3D print (1102) a scintillator layer onto the photodiode layer using a polymer, wherein the scintillator layer includes at least one geometric body, the at least one geometric body includes a scintillation material and a polymer, wherein the scintillation material is configured to convert incident ionizing radiation into non-ionizing electromagnetic radiation, and wherein the at least one geometric body is configured to direct the converted electromagnetic radiation into the at least one pixel using reflections inside the at least one geometric body; wherein the at least one geometric body is further configured to direct at least a portion of the converted electromagnetic radiation into the at least one pixel via the refractive index of the at least one geometric body that varies in a plane of the photodiode layer.

12. The method (1100) for manufacturing a radiation detector according to claim 11, further comprising: adding the scintillation material to the polymer prior to the 3D printing.

13. The method (1100) for manufacturing a radiation detector according to claim 11 or 12, wherein, Performing the 3D printing using one of the following: Stereolithography; Binder jetting; Fused deposition modeling; Digital light processing; Selective laser sintering; or Laminated object manufacturing.

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