CN114788001A

CN114788001A - Multi-layer image sensor

Info

Publication number: CN114788001A
Application number: CN202280001267.5A
Authority: CN
Inventors: 曹培炎; 刘雨润
Original assignee: Suzhou Frame View Intelligent Manufacturing Technology Co ltd
Current assignee: Suzhou Frame View Intelligent Manufacturing Technology Co ltd
Priority date: 2022-01-04
Filing date: 2022-01-04
Publication date: 2022-07-22
Also published as: WO2023130196A1

Abstract

An image sensor adapted to detect X-rays has an absorber layer, an electronics layer, and a printed circuit board. The active area of the absorption layer is configured to generate an electrical signal when the absorption layer absorbs incident X-ray photons. The printed circuit board and the active area do not overlap in an interlayer direction.

Description

Multi-layer image sensor

[ technical field ] A method for producing a semiconductor device

The present disclosure relates to image sensors, and more particularly to semiconductor X-ray detectors for imaging.

[ background of the invention ]

An X-ray detector may be used to measure the flux, spatial distribution, spectrum, or other properties of the X-rays.

X-ray imaging is a radiographic technique and can be used to reveal the internal structure of objects of non-uniform composition, such as the human body, which appear opaque to the naked eye. Semiconductor X-ray detectors operate by directly converting X-rays into electrical signals.

Radiographic imaging using semiconductor X-ray detectors provides numerous benefits over earlier developed techniques. Even so, advances in imaging based on semiconductor X-ray detectors are still desirable. It is desirable to reduce hole trapping caused by lattice defects (hole traps) in semiconductor X-ray detectors. It is further desirable to improve the X-ray detection accuracy or, in other words, to reduce the chance that the semiconductor X-ray detector will not detect incident X-ray photons.

[ summary of the invention ]

An image sensor suitable for detecting X-rays is disclosed herein. The image sensor includes an absorption layer, an electronics layer, and a printed circuit board. The absorption layer has an active area configured to generate an electrical signal when the absorption layer absorbs incident X-ray photons. The electronic device layer extends in a lateral direction parallel to the absorption layer. The electronic device layer overlaps the active region of the absorption layer in an interlayer direction. The interlayer direction is perpendicular to the transverse direction. The electronics layer is configured to receive and process electrical signals generated in the absorber layer. The printed circuit board includes at least one conductive layer and at least one non-conductive substrate. The conductive layer is laminated to the non-conductive substrate. The printed circuit board is configured to receive processed electrical signals from the electronics layer. The printed circuit board and the active area do not overlap in an interlayer direction.

According to an embodiment, the image sensor comprises a support layer. The support layer secures the absorbent layer, the electronics layer, and the printed circuit board relative to one another.

According to an embodiment, the support layer abuts the electronic device layer and the printed circuit board on a side of the electronic device layer opposite the absorption layer.

According to an embodiment, the support layer abuts the absorption layer and the printed circuit board on a side of the absorption layer opposite the electronic device layer.

According to an embodiment, the electrical connection between the electronics layer and the printed circuit board comprises a redistribution layer in the absorption layer.

According to an embodiment, the support layer has a linear attenuation coefficient of less than or equal to 43cm-1 at 5 keV.

According to an embodiment, the support layer has less than or equal to 20cm at 5keV²Mass attenuation coefficient per gram.

According to an embodiment, the support layer consists essentially of a fibre-reinforced plastic composite.

According to an embodiment, the fibers consist essentially of carbon.

According to an embodiment, the image sensor comprises an electrical connection between the absorption layer and the electronics layer, and an electrical connection between the electronics layer and the printed circuit board.

According to an embodiment, the electrical connection between the absorption layer and the electronic device layer comprises a bonding wire.

According to an embodiment, the electrical connection between the electronic device layer and the printed circuit board comprises a bonding wire.

According to an embodiment, the printed circuit board comprises a flexible cable.

According to an embodiment, the image sensor comprises at least one via between an electrical contact on the back side of the absorption layer and a circuit element on the front side of the electronic device layer.

According to an embodiment, the absorption layer forms a diode.

According to an embodiment, the absorption layer forms a resistor.

According to an embodiment, the electronic device layer forms an Application Specific Integrated Circuit (ASIC).

According to an embodiment, the support layer has a thickness of 0.5mm to 2 mm.

According to an embodiment, the support layer has a thickness of less than 10 mm.

According to an embodiment, the absorption layer has a thickness of 0.001mm to 1 mm.

According to an embodiment, the electronic device layer has a thickness of 0.001mm to 1 mm.

According to an embodiment, the printed circuit board has a thickness of 0.001mm to 1 mm.

According to an embodiment, a system includes an image sensor; and at least one of an X-ray source or an electron source.

According to an embodiment, the printed circuit board has a first portion and a second portion. The first portion includes a first proximal end and a first distal end. The first distal end extends laterally away from the first proximal end. The second portion includes a second proximal end and a second distal end. The first proximal end and the second proximal end meet at a common portion. The first distal end and the second distal end diverge from the common portion to form a concave transverse region. The concave lateral region is located between the first and second portions of the printed circuit board.

According to an embodiment, the image sensor comprises spacers in the concave lateral regions.

According to an embodiment, the spacer consists essentially of a fiber reinforced plastic composite. According to an embodiment, the fibers consist essentially of carbon.

According to an embodiment, an image sensor includes a first absorption layer, a first electronic device layer, a second absorption layer, a second electronic device layer, and a printed circuit board. The first absorbing layer is configured to generate a first electrical signal when it absorbs a first X-ray photon. The first electronics layer is configured to receive and process a first electrical signal from the first absorption layer. The first electronic device layer has a front side and a back side. The first absorbent layer has a front side and a back side. The front surface of the first electronic device layer abuts the back surface of the first absorber layer over the entire first active area. The second absorbing layer is configured to generate a second electrical signal when it absorbs a second X-ray photon. The second X-ray photon is a photon not absorbed by the first absorption layer. The second electronic device layer is configured to receive and process a second electrical signal from the second absorbing layer. The second absorbent layer has a front side and a back side. The second electronic device layer has a front side and a back side. The front surface of the second electronic device layer abuts the back surface of the second absorber layer over the entire second active area. The printed circuit board is configured to receive the processed first electrical signal from the first electronics layer. The printed circuit board is configured to receive the processed second electrical signal from the second electronics layer. The printed circuit board has a first portion, a second portion, a front side, and a back side. The first portion includes a first proximal end and a first distal end. The first distal end extends in a transverse plane away from the first proximal end. The second portion includes a second proximal end and a second distal end. The second distal end extends in a transverse plane away from the second proximal end. The first proximal end and the second proximal end meet at a common portion of the printed circuit board. The first distal end and the second distal end diverge from the common portion to form a concave transverse region. The concave lateral region is located between the first and second portions of the printed circuit board. The front side of the printed circuit board abuts the back side of the first electronic device layer over the entire first support margin. The first support margin overlaps the first portion and the second portion in an inter-layer direction perpendicular to the transverse plane. The first electronic device layer extends through the concave lateral region between the first and second portions of the printed circuit board. The back side of the printed circuit board abuts the front side of the second absorbent layer over the entire second support margin. The second support margin overlaps the first and second portions of the printed circuit board in the interlayer direction. The second absorption layer extends through the concave lateral region between the first and second portions of the printed circuit board. The first active area and the printed circuit board do not overlap in the interlayer direction. The second effective area and the printed circuit board do not overlap in the interlayer direction.

According to an embodiment, the printed circuit board does not surround at least one lateral edge of the concave lateral region.

[ description of the drawings ]

Fig. 1A shows a schematic side view according to an embodiment.

Fig. 1B shows a detailed schematic side view in accordance with an embodiment.

Fig. 1C shows a schematic top view according to an embodiment.

Fig. 2A shows a schematic top view according to an embodiment.

Fig. 2B shows a schematic side view in accordance with an embodiment.

Fig. 3 shows a schematic side view according to an embodiment.

Fig. 4A shows a schematic side view according to an embodiment.

Fig. 4B illustrates an exploded perspective view according to an embodiment.

Fig. 5A shows a schematic side view according to an embodiment.

Fig. 5B illustrates an exploded perspective view according to an embodiment.

Fig. 6 shows a schematic side view according to an embodiment.

Fig. 7A shows a schematic side view according to an embodiment.

Fig. 7B illustrates a partial cross-sectional view according to an embodiment.

Fig. 8A shows a schematic top view according to an embodiment.

Fig. 8B illustrates a perspective view according to an embodiment.

Fig. 8C shows an exploded perspective view according to an embodiment.

Fig. 9 illustrates an exploded perspective view according to an embodiment.

[ detailed description ] embodiments

Fig. 1A schematically shows a side view of an image sensor, i.e. a semiconductor X-ray detector 100, according to an embodiment. The semiconductor X-ray detector 100 may include an X-ray absorption layer 110, an electronic device layer 120 (e.g., an application specific integrated circuit or ASIC) for processing or analyzing electrical signals generated in the X-ray absorption layer 110 by incident X-rays, and a Printed Circuit Board (PCB)140 carrying the processed electrical signals from the electronic device layer 120 to other electrical or electronic components. The X-ray absorbing layer 110 may include a semiconductor material, such as silicon, germanium, GaAs, CdTe, CdZnTe, or a combination thereof. The PCB140 may include at least one conductive layer 141 laminated with at least one non-conductive substrate 143. The conductive layer 141 may include one or more conductive materials, such as copper, aluminum, tin, gold, or combinations thereof. The non-conductive substrate 143 may include one or more electrical insulators, such as glass cloth, epoxy, polyimide, polyester, polyethylene naphthalate (PEN), or Polytetrafluoroethylene (PTFE). Fig. 1A shows the conductive layer 141 sandwiched between two non-conductive substrates 143, but in other embodiments only one non-conductive substrate 143 is used. In other embodiments, more than two non-conductive substrates 143 are used. In some embodiments, the PCB140 is a flexible cable, such as a ribbon cable.

As shown in fig. 1A, according to an embodiment, the X-ray absorbing layer 110 extends laterally (across the page in the X-direction and/or into the page in the y-direction). The electronic device layer 120 also extends laterally (across the page in the x-direction and/or into the page in the y-direction). The X-ray absorbing layer 110 and the electronic device layer 120 are joined in the interlayer (z) direction. The PCB140 extends laterally (in the x-direction across the page and/or in the y-direction into the page). The electronic device layer 120 and the PCB140 are joined in the interlayer (z) direction.

When an X-ray photon strikes X-ray absorbing layer 110, X-ray absorbing layer 110 may absorb the X-ray photon and generate one or more charge carriers (e.g., electron and hole pairs) by various mechanisms. However, when an X-ray photon encounters a hole trap (e.g., a lattice defect) for a hole, it may be trapped by the hole trap (e.g., lattice defect).

Fig. 1B schematically shows an image sensor, i.e. a semiconductor X-ray detector 100, according to an embodiment. The X-ray detector 100 may include an X-ray absorption layer 110, an electronics layer 120 (e.g., ASIC) for processing or analyzing electrical signals generated in the X-ray absorption layer 110 by incident X-rays, and a PCB 140. In some embodiments, the X-ray absorbing layer 110 includes a diode. In some embodiments, the X-ray absorbing layer 110 includes a resistor.

The X-ray absorbing layer 110 may include one or more diodes (e.g., p-i-n or p-n) formed from one or more discrete regions 114 of the first and second

doped regions

111 and 113. In some embodiments, the second doped region 113 may be separated from the first doped region 111 by the intrinsic region 112. The discrete regions 114 may be separated from each other by the first doped region 111 or the intrinsic region 112. The first and second

doped regions

111, 113 may have opposite type doping (e.g., region 111 is p-type and region 113 is n-type, or region 111 is n-type and region 113 is p-type). In the example of fig. 1B, each discrete region 114 of the second doped region 113 forms a diode with the first doped region 111 and the intrinsic region 112. That is, the X-ray absorption layer 110 has a plurality of diodes having the first doped region 111 as a common electrode. In other embodiments, the first doped region 111 may have discrete portions. In some embodiments, the X-ray absorbing layer includes electrical contacts 119B formed as discrete portions, each of which is in electrical contact with one of the discrete regions 114. The plurality of diodes may have electrical contact 119A as a common (common) electrode.

When an X-ray photon strikes X-ray absorbing layer 110, X-ray absorbing layer 110 may absorb the X-ray photon and generate one or more charge carriers by various mechanisms. X-ray photons may generate 10 to 100000 charge carriers. Charge carriers may drift under an electric field to an electrode of one of the diodes. The field may be an external electric field. In various embodiments, the charge carriers may drift in directions such that the charge carriers generated by a single X-ray photon are not substantially shared by two different discrete regions 114 (where "substantially not … … shared" means that less than 5%, less than 2%, or less than 1% of the charge carriers flow to one different discrete region 114 compared to the rest of the charge carriers). In some embodiments, charge carriers generated by a single X-ray photon may be shared by two different discrete regions 114.

Fig. 1C shows an exemplary top view of a portion of the semiconductor X-ray detector 100 having a 4X 4 array of discrete regions 114. According to some embodiments, charge carriers generated by X-ray photons incident around a footprint of one of the discrete regions 114 are substantially not shared with another of the discrete regions 114. The area around a discrete region 114 is referred to as a pixel associated with that discrete region 114, wherein substantially all (greater than 95%, greater than 98%, or greater than 99%) of the charge carriers generated by X-ray photons incident therein flow to the discrete region 114. That is, less than 5%, less than 2%, or less than 1% of these charge carriers flow through the pixel. By measuring the drift current flowing into each discrete region 114, or the rate of change of voltage of each discrete region 114, the number of absorbed X-ray photons (related to the incident X-ray intensity) and/or their energy in the pixel associated with the discrete region 114 can be determined. Thus, the spatial distribution (e.g., image) of the incident X-ray intensity can be determined by measuring the drift current into each of the array of discrete regions 114 individually, or by measuring the rate of change of voltage of each of the array of discrete regions 114.

Referring again to fig. 1B, electronics layer 120 may include electronics system 121 suitable for processing or interpreting signals generated by X-ray photons incident on X-ray absorbing layer 110. In various embodiments, electronic system 121 includes analog circuits such as filter networks, amplifiers, integrators, and comparators. In some embodiments, electronic system 121 includes digital circuits, such as microprocessor 124 and memory 126. The electronic system 121 may include components that are common to the pixels or components that are dedicated to individual pixels. For example, the electronic system 121 may include an amplifier dedicated to each pixel, and the microprocessor 124 and memory 126 may be shared among all pixels.

Fig. 1B shows an embodiment in which the electronic system 121 is electrically connected to the pixels through vias 131. The space between the through holes 131 may be filled with a filling material 130, which may increase the mechanical stability of the connection of the electronic device layer 120 with the X-ray absorption layer 110. In other embodiments, other bonding techniques may be used to connect the electronic system 121 to the pixels without using vias.

In some embodiments, the electronic system 121 may be electrically connected to the PCB140 through the via 151. The space between the vias 151 may be filled with a filler material 150, which may increase the mechanical stability of the connection of the electronic device layer 120 with the PCB 140. In other embodiments, other bonding techniques may be used to connect the electronic system 121 to the PCB 140.

Various effects may occur with respect to the thickness of the absorbing layer (e.g., absorbing layer 110). For example, for a given material, it has been observed that a thinner absorption layer may allow more X-ray photons to pass therethrough without being absorbed, while a thicker absorption layer may allow less X-ray photons to pass therethrough without being absorbed. Thus, in situations where it is desirable to detect and form an image of the maximum number of X-ray photons, it may be desirable to maximize the thickness of the absorption layer under other constraints.

On the other hand, it has been observed that thinner absorber layers may have fewer physical defects (e.g., lattice defects), while thicker absorber layers may have more physical defects (e.g., lattice defects). Upon absorption of an X-ray photon, pairs of negative and positive charge carriers (e.g., electron and hole pairs) may be generated in the absorbing layer (e.g., absorbing layer 110). Some of these electrons and holes may recombine while others may escape from the absorbing layer. Since electrons have higher mobility than holes, electrons can escape from the absorbing layer more easily than holes. Some physical defects in the absorber layer (e.g., lattice defects or hole traps) may cause holes to be trapped. Over time, holes accumulate, which may qualitatively degrade the performance of the absorber layer. Therefore, where it is desirable to minimize hole accumulation, it may be desirable to minimize the thickness of the absorber layer under other constraints.

According to various embodiments disclosed, a semiconductor X-ray detector may comprise features that allow stacking of multiple absorption layers in the inter-layer direction, such that X-ray photons that are not absorbed by a first absorption layer may be absorbed by a second (or subsequent) absorption layer. Thus, a relatively thin absorbing layer (characterized by fewer lattice defects or hole traps) can be used while achieving an overall absorption and detection rate comparable to or higher than a single relatively thick absorbing layer.

Fig. 2A schematically shows a top view of an image sensor, i.e. a semiconductor X-ray detector 200, according to an embodiment. Fig. 2B schematically shows a side view of the semiconductor X-ray detector 200. The X-ray detector 200 includes an absorption layer 210, an electronics layer 220, a Printed Circuit Board (PCB)240, and a support layer 250. PCB 240 has a conductive layer 241 sandwiched between two non-conductive substrates 243. When an X-ray photon encounters absorbing layer 210, it is absorbed and a corresponding electrical signal appears in absorbing layer 210.

In fig. 2A and 2B, the absorption layer 210 extends laterally (e.g., in the x-direction and the y-direction). The inter-layer (z) direction is perpendicular to the lateral (e.g., x and y) extent of the absorber layer 210. The electronic device layer 220 adjoins the absorber layer 210 in the interlayer (z) direction. The electronic device layer 220 extends laterally (e.g., in one or both of the x-direction and the y-direction) parallel to the absorber layer 210. The active area 215 of the absorber layer 210 corresponds to the area where the electronic device layer 220 and the absorber layer 210 overlap. When the X-ray detector 200 is viewed from the top (parallel to the z-direction), the lateral (e.g., X and y) extent of the active area 215 can be seen, as shown in fig. 2A. When the X-ray detector is viewed from the side (parallel to the y-direction), the lateral (e.g., X) extent of the active area 215 can be seen, as shown in fig. 2B.

The absorber layer 210 has a back surface 214 and the electronic device layer 220 has a front surface 222. According to various embodiments, the active area 215 covers the interface between the back surface 214 and the front surface 222, as shown in fig. 2B. The pixels in the absorption layer 210 are provided with respective circuit elements (e.g., analog circuits such as filter networks, amplifiers, integrators, and comparators, and/or digital circuits such as microprocessors and memories) in the electronic device layer 220 throughout the active area 215, whereby a spatial distribution (e.g., an image) of incident X-rays can be obtained.

In fig. 2A and 2B, the electronic device layer 220 includes an extended portion 201 that extends laterally (here, in the X direction) across a lateral edge of the absorption layer 210. In some embodiments, bond wires 231 electrically connect the absorber layer 210 at a location in the active area 215 to the electronic device layer 220 at a location in the extension 201. As shown in fig. 2B, the extension 201 is outside the active area 215.

As shown in fig. 2B, the electronic device layer 220 and the PCB 240 may be mounted on a support layer 250. Thus, in some embodiments, the support layer 250 secures the absorbent layer 210, the electronics layer 220, and the PCB 240 relative to one another. The absorber layer 210 and the support layer 250 may abut the electronic device layer 220 on opposite sides of the electronic device layer 220 in the inter-layer (z) direction. In other words, the electronic device layer 220 is sandwiched between the absorption layer 210 and the support layer 250.

The space 203 may separate the PCB 240 from the electronics layer 220 laterally (here, in the x-direction). In some embodiments, the space 203 is open to the atmosphere. In other embodiments, the space 203 is sealed. In some embodiments, a gas (e.g., air) fills all or part of space 203. In some embodiments, the spacers fill all or part of the space 203. In some embodiments, PCB 240 is directly against electronics layer 220 in a lateral direction. In some embodiments, bond wires 233 electrically connect electronic device layer 220 to PCB 240.

As shown in fig. 2B, a gap 205 separates the absorber layer 210 from the PCB 240. The gap 205 may provide lateral separation due to one or both of the extension 201 and the space 203, such that there is no overlap between the active area 215 and the PCB 240 in the inter-layer (z) direction.

According to various embodiments, the support layer 250 provides mechanical support for both the electronics layer 220 and the PCB 240. In some embodiments, the support layer 250 has a stiffness greater than or equal to a corresponding stiffness of the electronics layer 220 and the PCB 240.

According to various embodiments, it may be desirable to allow X-ray photons to pass through the support layer 250. Thus, in some embodiments, the support layer 250 is configured in such a way that it has less than or equal to 43cm at 5keV^-1(one per 43cm at 5 kev) linear attenuation coefficient. In some embodiments, the support layer 250 is formed from a material having a thickness of less than or equal to 20cm at 5keV²A mass attenuation coefficient per gram (20 square centimeters per gram at 5 kilo-electron volts) or a combination of materials. In some embodiments, the support layer 250 comprises a fiber reinforced plastic composite (e.g., glass fiber, carbon fiber, etc.).

In various embodiments, the support layer 250 has a thickness of 0.25mm to 1mm, 0.5mm to 2mm, or 1mm to 3 mm. In other embodiments, the support layer 250 has a thickness of less than 0.25mm or greater than 3mm and less than 10 mm. In various embodiments, the absorbent layer 210 has a thickness of 0.001mm to 1mm, 0.01mm to 1.5mm, or 0.5mm to 2 mm. In other embodiments, the absorbent layer 210 has a thickness of less than 0.001mm or greater than 2 mm. In various embodiments, the electronic device layer 220 has a thickness of 0.001mm to 1mm, 0.01mm to 1.5mm, or 0.5mm to 2 mm. In other embodiments, the electronic device layer 220 has a thickness of less than 0.001mm or greater than 2 mm.

Fig. 3 schematically shows a side view of an image sensor, i.e. a semiconductor X-ray detector 300, according to an embodiment. The X-ray detector 300 includes an absorption layer 310, an electronics layer 320, a Printed Circuit Board (PCB)340, and a support layer 350. The PCB340 has a conductive layer 341 sandwiched between two non-conductive substrates 343. When an X-ray photon encounters absorbing layer 310, it is absorbed and a corresponding electrical signal appears in absorbing layer 310.

In fig. 3, the absorber layer 310 extends laterally (e.g., in the x-direction). The interlaminar (z) direction is perpendicular to the lateral (x) extent of the absorber layer 310. The electronic device layer 320 adjoins the absorber layer 310 in the interlayer (z) direction. The electronic device layer 320 extends laterally (e.g., in the x-direction) parallel to the absorber layer 310. The active area 315 of the absorber layer 310 corresponds to the area where the electronic device layer 320 and the absorber layer 310 overlap.

Absorber layer 310 has a back surface 314 and electronic device layer 320 has a front surface 322. According to various embodiments, active area 315 covers the interface between back side 314 and front side 322. Pixels in the absorber layer 310 are provided with corresponding circuit elements (e.g., analog circuits such as filter networks, amplifiers, integrators, and comparators, and/or digital circuits such as microprocessors and memories) in the electronics layer 320 throughout the active area 315, whereby a spatial distribution (e.g., image) of incident X-rays can be obtained.

In fig. 3, the absorber layer 310 includes an extension 301 that extends laterally (here, in the X-direction) across a lateral edge of the electronic device layer 320. In some embodiments, a redistribution layer (RDL) electrically connects the electronic device layer 320 at a location in the active area 315 to the absorption layer 310 at a location in the extension portion 301. As shown in fig. 3, the extension 301 is outside the active area 315.

As shown in fig. 3, absorption layer 310 and PCB340 may be mounted on support layer 350. Thus, in some embodiments, support layer 350 secures absorber layer 310, electronic device layer 320, and PCB340 relative to one another. Support layer 350 and electronic device layer 320 may abut absorber layer 310 on opposite sides of absorber layer 310 in the inter-layer (z) direction. In other words, the absorption layer 310 is sandwiched between the support layer 350 and the electronic device layer 320.

The space 303 may separate the PCB340 from the absorber layer 310 laterally (here, in the x-direction). In some embodiments, the space 303 is open to the surrounding atmosphere. In other embodiments, the space 303 is sealed. In some embodiments, a gas (e.g., air) fills all or a portion of space 303. In some embodiments, the spacers fill all or part of the space 303. In some embodiments, PCB340 is directly against electronic device layer 320 in a lateral direction. In some embodiments, bond wires 333 electrically connect absorber layer 310 to PCB 340.

As shown in fig. 3, a gap 305 separates the electronics layer 320 from the PCB 340. The gap 305 may provide lateral separation due to one or both of the extension 301 and the space 303, such that there is no overlap between the active area 315 and the PCB340 in the inter-layer (z) direction.

According to various embodiments, support layer 350 provides mechanical support for both absorbent layer 310 and PCB 340. In some embodiments, the stiffness of support layer 350 is greater than or equal to the respective stiffness of absorbent 310 and PCB 340.

According to various embodiments, it may be desirable to allow X-ray photons to pass through support layer 350. Thus, in some embodiments, support layer 350 is configured in such a way that it has less than or equal to 43cm at 5keV^-1(one per 43cm at 5 kev) linear attenuation coefficient. In some embodiments, support layer 350 is formed from a material having a resistivity less than or equal to 5keV20cm²A mass attenuation coefficient per gram (20 square centimeters per gram at 5 kilo-electron volts) or a combination of materials. In some embodiments, support layer 350 comprises a fiber reinforced plastic composite (e.g., glass fiber, carbon fiber, etc.).

In various embodiments, support layer 350 has a thickness of 0.25mm to 1mm, 0.5mm to 2mm, or 1mm to 3 mm. In other embodiments, support layer 350 has a thickness of less than 0.25mm, or greater than 3mm and less than 10 mm. In various embodiments, the absorbent layer 310 has a thickness of 0.001mm to 1mm, 0.01mm to 1.5mm, or 0.5mm to 2 mm. In other embodiments, the absorbent layer 310 has a thickness of less than 0.001mm or greater than 2 mm. In various embodiments, the electronic device layer 320 has a thickness of 0.001mm to 1mm, 0.01mm to 1.5mm, or 0.5mm to 2 mm. In other embodiments, the electronic device layer 320 has a thickness of less than 0.001mm or greater than 2 mm.

Fig. 4A schematically shows a side view of an image sensor, i.e. a semiconductor X-ray detector 400, according to an embodiment. Fig. 4B schematically shows an exploded perspective view of an image sensor (i.e., the semiconductor X-ray detector 400) according to an embodiment. The X-ray detector 400 combines aspects of the X-ray detector 200 (see fig. 2A, 2B) and the X-ray detector 300 (see fig. 3). The X-ray detector 400 includes a first absorption layer 210, a first electronic device layer 220, a first PCB 240, a second absorption layer 310, a second electronic device layer 320, a second PCB340, and a support layer 450.

Referring to fig. 4A and 4B, X-ray photons may be absorbed by the first absorption layer 210 or the second absorption layer 310. When the first absorption layer 210 absorbs an X-ray photon, it generates a corresponding electrical signal that is received by one or more circuit elements in the first electronic device layer 220 in substantially the same manner as discussed for the related embodiments. In some cases, however, the X-ray photons may pass through the first absorption layer 210 without being absorbed. In such cases, it may be desirable to facilitate absorption (and thus detection and imaging) of other undetected X-ray photons. Thus, according to various embodiments, the support layer 450 may be interposed between the first and second

absorbent layers

210, 310 in the inter-layer (z) direction. In this manner, unabsorbed X-ray photons in the first absorption layer 210 may be absorbed in the second absorption layer 310.

More specifically, because the first absorber layer 210 abuts the corresponding electronic device layer 220, in some embodiments, the support layer 450 is sandwiched between the first electronic device layer 220 and the second absorber layer 310 in the inter-layer (z) direction. Thus, X-ray photons that are not absorbed in the first absorption layer 210 may pass through the first absorption layer 210, the first electronic device layer 220, and the support layer 450 before being absorbed in the second absorption layer 310, thereby generating corresponding electrical signals that are received by one or more circuit elements in the second electronic device layer 320. In some embodiments, both the first electronics layer 220 and the second electronics layer 320 are connected to a system (e.g., a microprocessor, such as a digital signal processor or DSP) by which a spatial distribution of incident X-ray intensity (e.g., an image) can be determined.

In some embodiments, the support layer 450 is configured in such a way that it has less than or equal to 43cm at 5keV^-1(one per 43cm at 5 kev). In some embodiments, support layer 450 is made of a material having a thickness of less than or equal to 20cm at 5keV²A mass attenuation coefficient per gram (20 square centimeters per gram at 5 kilo-electron volts) or a combination of materials. In some embodiments, the support layer 450 includes a fiber reinforced plastic composite (e.g., glass fiber, carbon fiber, etc.). In various embodiments, the support layer 450 has a thickness of 0.25mm to 1mm, 0.5mm to 2mm, or 1mm to 3 mm. In other embodiments, the support layer 450 has a thickness of less than 0.25mm or greater than 3mm and less than 10 mm.

As shown in fig. 4A and 4B, the first active area 215 of the first absorption layer 210 does not overlap the first PCB 240 in the inter-layer (z) direction. Also, the second active area 315 of the second absorption layer 310 does not overlap the second PCB340 in the interlayer (z) direction. The first active area 215 is laterally spaced apart from the first PCB 240 by the first extension 201 and the first space 203. The second active area is laterally spaced apart from the second PCB340 by the second extension 301 and the second space 303. In some embodiments, the first PCB 240 overlaps the second PCB340 in the inter-layer (z) direction. For example, as shown in fig. 4A and 4B, the first PCB 240 and the second PCB340 may be aligned in the lateral (x and y) direction. In other embodiments, the first PCB 240 and the second PCB340 partially overlap in the inter-layer (z) direction. In other embodiments, no portion of the first PCB 240 and the second PCB340 overlap in the inter-layer (z) direction.

Fig. 5A schematically shows a side view of an image sensor, i.e. a semiconductor X-ray detector 500, according to an embodiment. Fig. 5B schematically shows an exploded perspective view of the X-ray detector 500. The X-ray detector 500 comprises an absorption layer 510, an electronics layer 520 and a Printed Circuit Board (PCB)540, the Printed Circuit Board (PCB)540 having a conductive layer 541 laminated to a non-conductive substrate 543. The PCB 540 has a first portion 540a and a second portion 540b laterally spaced from the first portion 540 a. The aperture 545 extends laterally between the first and

second portions

540a, 540b of the PCB 540. The holes 545 (see, e.g., fig. 5B) are one example of a concave lateral region surrounded by the first, second, third and

fourth portions

540a, 540B, 540c, 540d of the PCB 540. In other embodiments, the recessed area may have one or more edges that are not surrounded by any portion of an adjacent printed circuit board. (see, for example, fig. 8A, 8B, 8C, and 9).

In some embodiments, the apertures 545 are open to the surrounding atmosphere. In other embodiments, the aperture 545 is sealed. In some embodiments, a gas (e.g., air) fills all or a portion of holes 545. In some embodiments, spacers 530 fill all or part of holes 545. In some embodiments, both the spacers 530 and the PCB 540 provide mechanical support to the adjacent electronic device layer 520. In some embodiments, spacers 530 are configured in such a way that they have a length of less than or equal to 43cm at 5keV^-1(one per 43cm at 5 kev). In some embodiments, spacers 530 are made of a material having a length of less than or equal to 20cm at 5keV²A material or combination of materials having a mass attenuation coefficient of/g (20 square centimeters per gram at 5 kilo electron volts). In some embodiments, spacer 530 comprises a fiber reinforced plastic composite(e.g., glass fibers, carbon fibers, etc.).

The back side 524 of the electronics layer 520 abuts the front side 542 of the PCB 540. The back surface 514 of the absorber layer 510 abuts the front surface 522 of the electronic device layer 520. The active region 515 is formed in the lateral (x and y) range of the interface between the absorber layer 510 and the electronic device layer 520.

As shown in fig. 5A and 5B, the electronic device layer 520 includes an extended portion 501 that extends laterally across a lateral edge of the absorber layer 510. In some embodiments, bond wire 531 electrically connects a location in active area 515 to a location in extension portion 501. The extension 501 is laterally outward of the active area 215.

As shown in fig. 5B, the support margin 507 refers to an area where the extension portion 501 overlaps the PCB 540. The support margin 507 and the active area 515 do not overlap in the inter-layer (z) direction.

Electronic device layer 520 extends laterally in the x-direction to overlap first portion 540a, aperture 545, spacer 530 (if present), and second portion 540 b. Electronic device layer 120 extends laterally in the y-direction to overlap third portion 540c, aperture 545, spacer 530 (if present), and fourth portion 540 d. The lateral (x and y) extent of the aperture 545 and extension 501 is such that the active area 515 and PCB 540 do not overlap. Thus, in some embodiments, the electronics layer 520 mechanically secures the absorber layer 510 relative to the PCB 540, but the active area 515 does not overlap the PCB 540 in the inter-layer (z) direction.

As shown in fig. 5B, in some embodiments, the aperture 545 may have a square shape. In other embodiments, the aperture 545 can have other shapes (e.g., oval, circular, rectangular, triangular, pentagonal, hexagonal, polygonal, or a closed curve). In some embodiments, the opposing portions (e.g., the first and

second portions

540a, 540b, or the third and

fourth portions

540c, 540d) of the PCB 540 are parallel. In other embodiments, opposing portions of PCB 540 are not parallel. In some embodiments, the angle θ (theta) between the first portion 540a and the third portion 540c is 90 degrees. In other embodiments, various portions of the PCB 540 (e.g., portion 540a, portion 540b, portion 540c, or portion 540d) are spaced apart at an angle that is less than, greater than, or equal to 90 degrees. For example, in some embodiments, the plurality of apertures 545 form an array (e.g., a rectangular grid, a triangular grid, a hexagonal honeycomb) across the area of the PCB 540. Some embodiments include a plurality of apertures 545 of uniform shape and size. Some embodiments include a plurality of apertures 545 having non-uniform shapes and sizes.

Fig. 6 schematically shows a side view of an image sensor, i.e. a semiconductor X-ray detector 600, according to an embodiment. X-ray detector 600 includes an absorption layer 610, an electronics layer 620, and a Printed Circuit Board (PCB) 640. The PCB 640 has a conductive layer 641 laminated to a non-conductive substrate 643. The PCB 640 has a first portion 640a and a second portion 640b laterally spaced from the first portion 640 a. The aperture 645 extends laterally between the first and

second portions

640a, 640 b.

In some embodiments, the aperture 645 is open to the surrounding atmosphere. In other embodiments, aperture 645 is sealed. In some embodiments, a gas (e.g., air) fills all or part of aperture 645. In some embodiments, spacers 630 fill all or part of aperture 645. In some embodiments, both the spacers 630 and the PCB 640 provide mechanical support to the adjacent absorber layer 610. In some embodiments, spacers 630 are configured in such a way that they have less than or equal to 43cm at 5keV^-1(one per 43cm at 5 kev). In some embodiments, spacers 630 are made from a material having less than or equal to 20cm at 5keV²A material or combination of materials having a mass attenuation coefficient of/g (20 square centimeters per gram at 5 kilo electron volts). In some embodiments, spacer 630 comprises a fiber reinforced plastic composite (e.g., fiberglass, carbon fiber, etc.).

The front side 612 of the absorber layer 610 abuts the back side 644 of the PCB 640. The front side 622 of the electronic device layer 620 abuts the back side 614 of the absorber layer 610. The active region 615 is formed within the lateral (x and y) extent of the interface between the absorber layer 610 and the electronic device layer 620.

As shown in fig. 56, the absorber layer 610 includes an extension 601 that extends laterally across a lateral edge of the electronic device layer 620. In some embodiments, bond wires 631 electrically connect a location in the active area 615 to a location in the extension 601. The extension 601 is laterally outward of the active area 615.

The absorbing layer 610 extends laterally in the x-direction to overlap the first portion 640a, the aperture 645, the spacer 630 (if present), and the second portion 640 b. The lateral extent of the aperture 645 and the extension 601 is such that the active area 615 and the PCB 640 do not overlap. Thus, in some embodiments, the absorber layer 610 mechanically fixes the electronic device layers relative to the PCB 640, but the active area 615 does not overlap the PCB 640 in the inter-layer (z) direction.

Fig. 7A schematically shows a side view of an image sensor, i.e. a semiconductor X-ray detector 700, according to an embodiment. Fig. 7B schematically shows a partial cross-sectional view of the semiconductor X-ray detector 700 according to an embodiment. X-ray detector 700 combines aspects of X-ray detector 500 (see fig. 5A, 5B) and X-ray detector 600 (see fig. 6). X-ray detector 700 includes first absorption layer 510, first electronics layer 520, second absorption layer 610, second electronics layer 620, and PCB 740. The PCB 740 includes a conductive layer 741 sandwiched between two non-conductive substrates 743.

Referring to fig. 7A, X-ray photons may be absorbed by the first absorption layer 510 or the second absorption layer 610. When the first absorption layer 510 absorbs an X-ray photon, it generates a corresponding electrical signal that is received by one or more circuit elements in the first electronic device layer 520 in substantially the same manner as discussed for the related embodiments. In some cases, however, the X-ray photons may pass through the first absorption layer 510 without being absorbed. In such cases, it may be desirable to facilitate absorption (and thus detection and imaging) of other undetected X-ray photons. Thus, according to various embodiments, where an aperture 745 is provided in the PCB 740 to facilitate the passage of X-ray photons, the PCB 740 may be interposed between the first and second absorption layers 510, 610 in the inter-layer (z) direction. In this manner, unabsorbed X-ray photons in the first absorption layer 510 may be absorbed in the second absorption layer 610.

More specifically, because the first absorber layer 510 abuts the corresponding electronic device layer 520, in some embodiments, the PCB 740 (including the aperture 745) is sandwiched between the first electronic device layer 520 and the second absorber layer 610 in the inter-layer (z) direction. Thus, X-ray photons that are not absorbed in the first absorption layer 510 may pass through the first absorption layer 510, the first electronic device layer 520, and the aperture 745 before being absorbed in the second absorption layer 610, thereby generating a corresponding electrical signal in the second absorption layer 610 and which is received by one or more circuit elements in the second electronic device layer 620. In some embodiments, both the first electronics layer 520 and the second electronics layer 620 are connected to a system (e.g., a microprocessor, such as a digital signal processor or DSP) by which the spatial distribution of incident X-ray intensity (e.g., an image) can be determined.

In some embodiments, the aperture 745 is open to the surrounding atmosphere. In other embodiments, the aperture 745 is sealed. In some embodiments, a gas (e.g., air) fills all or a portion of the aperture 745. In some embodiments, the spacer 730 fills all or part of the aperture 745. In some embodiments, both the spacer 730 and the PCB 740 provide mechanical support to the adjacent first electronic device layer 520 and second absorber layer 610. In some embodiments, spacers 730 are configured in such a way that they have a length of less than or equal to 43cm at 5keV^-1(one per 43cm at 5 kev) linear attenuation coefficient. In some embodiments, spacers 730 are made of a material having a length of less than or equal to 20cm at 5keV²A material or combination of materials having a mass attenuation coefficient of/g (20 square centimeters per gram at 5 kilo electron volts). In some embodiments, spacer 730 comprises a fiber reinforced plastic composite (e.g., glass fiber, carbon fiber, etc.).

As shown in fig. 7B, according to an embodiment, the PCB 740 may include an array of rectangular holes 745 (e.g., a 3 x 3 grid). In other embodiments, the aperture 745 may have another shape (e.g., triangular, hexagonal). Some embodiments include a plurality of apertures 745 each having a uniform shape and size. Some embodiments include a plurality of apertures 745 having non-uniform shapes and sizes.

In various embodiments, the PCB 740 has a thickness of 0.25mm to 1mm, 0.5mm to 2mm, or 1mm to 3 mm. In other embodiments, the PCB 740 has a thickness of less than 0.25mm or greater than 3mm and less than 10 mm. In various embodiments, the first electronic device layer 520 has a thickness of 0.001mm to 1mm, 0.01mm to 1.5mm, or 0.5mm to 2 mm. In other embodiments, the first electronic device layer 520 has a thickness less than 0.001mm or greater than 2 mm. In various embodiments, the second absorbent layer 610 has a thickness of 0.001mm to 1mm, 0.01mm to 1.5mm, or 0.5mm to 2 mm. In other embodiments, the second absorbent layer 610 has a thickness of less than 0.001mm or greater than 2 mm.

Fig. 8A schematically shows a top view of an image sensor, i.e. a semiconductor X-ray detector 800, according to an embodiment. Fig. 8B schematically shows a perspective view of the X-ray detector 800 according to an embodiment. Fig. 8C schematically illustrates an exploded perspective view of the X-ray detector 800 according to an embodiment.

X-ray detector 800 includes an absorption layer 810, an electronics layer 820, and a Printed Circuit Board (PCB) 840. PCB 840 has a conductive layer 841 sandwiched between two non-conductive substrates 843. The absorber layer 810 abuts the electronic device layer 820 over the entire active area 815. The electronic device layer 820 abuts the PCB 840 over the entire support margin 807. The PCB 840 has a first portion 846 and a second portion 848.

The first portion 846 has a first proximal end 846a and a first distal end 846 b. The second portion 848 has a second proximal end 848a and a second distal end 848 b. The first proximal end 846a and the second proximal end 848a are connected and meet at a common portion 847. The first distal end 846b and the second distal end 848b diverge from the common portion 847 to form a concave transverse area 845 between the first portion 846 and the second portion 848.

In some embodiments, the first portion 846 and the second portion 848 form an angle θ (theta) in the transverse (x-y) plane, or in other words, in a plane perpendicular to the inter-layer (z) direction. In some embodiments, the angle θ (theta) is 90 degrees. In other embodiments, the angle θ (theta a) is less than or greater than 90 degrees.

Still referring to fig. 8A, 8B, and 8C, the support margin 807 overlaps the first portion 846 and the second portion 848 in the inter-layer (z) direction. In some embodiments, the lateral gap 805 separates the first portion 846 and the second portion 848 from the closest lateral edges of the active area 815 of the absorbent layer 810. In various embodiments, the lateral gap 805 has a width of 0.0001mm to 0.1mmmm, 0.01mm to 1mm, or 0.1mm to 2 mm. In other embodiments, the lateral gap 805 has a width less than 0.0001mm or greater than 2 mm. In various embodiments, the supporting margin 807 has a lateral width of 0.0001mm to 0.1mm, 0.01mm to 1mm, or 0.1mm to 2 mm. In other embodiments, the support margin 807 has a lateral width less than 0.0001mm or greater than 2 mm.

In some embodiments, PCB 840 supports absorbent layer 810 and electronic device layer 820 on at least one lateral edge, but does not support absorbent layer 810 and electronic device layer 820 on at least another lateral edge. For example, as shown in fig. 8A, 8B, and 8C, the electronics layer 820 has a generally rectangular shape and the PCB 840 has an "L" shape, where the first portion 846 and the second portion 848 correspond to the legs of the "L". The first portion 846 overlaps an adjacent edge of the electronic device layer 820 in the inter-layer (z) direction, and the second portion 848 overlaps another adjacent edge of the electronic device layer 820 in the inter-layer (z) direction. However, the PCB 840 does not overlap the other two lateral edges of the electronic device layer 820 in the inter-layer (z) direction.

In some embodiments, concave lateral region 845 is open to the surrounding atmosphere. In other embodiments, the concave transverse region 845 is sealed. In some embodiments, a gas (e.g., air) fills all or a portion of concave transverse region 845. In some embodiments, spacers 830 fill all or part of concave lateral region 845. In some embodiments, both the spacers 830 and the PCB 840 provide mechanical support to the adjacent electronic device layer 820. In some embodiments, the spacers 830 are configured in such a way that they have less than or equal to 43cm at 5keV^-1(one per 43cm at 5 kev). In some embodiments, spacers 830 are made of a material having less than or equal to 20cm at 5keV²A mass attenuation coefficient per gram (20 square centimeters per gram at 5 kilo-electron volts) or a combination of materials. In some embodiments, spacer 830 comprises a fiber reinforced plastic compositeMaterials (e.g., glass fibers, carbon fibers, etc.).

Fig. 9 schematically shows an exploded perspective view of an image sensor, i.e. a semiconductor X-ray detector 900, according to an embodiment. The X-ray detector 900 includes a first absorption layer 810, a first electronics layer 820, and a Printed Circuit Board (PCB)840, substantially as discussed with respect to the embodiments of the X-ray detector 800 shown in fig. 8A, 8B, and 8C. Further, the X-ray detector 900 includes a second absorption layer 910 and a second electronics layer 920.

The second absorption layer 910 abuts the second electronic device layer 920 over the entire second active area 915. On the opposite side of the PCB 840 from the first support margin 807, the second absorbent layer 910 abuts the PCB 840 over the entire second support margin 907. Thus, according to various embodiments, PCB 840 may be interposed between first and second

absorbent layers

810 and 910 in the inter-layer (z) direction. In this manner, unabsorbed X-ray photons in the first absorption layer 810 may be absorbed in the second absorption layer 910. More specifically, in some embodiments, the PCB 840 and the spacer 830 (if present) are sandwiched between the first electronic device layer 820 and the second absorption layer 910 in the inter-layer (z) direction, and the first active area 815 and the second active area 915 do not overlap the PCB 840 in the inter-layer (z) direction.

According to various embodiments, a physical component (e.g., a spacer) is said to consist essentially of a fiber reinforced plastic composite when the component comprises less than 5%, less than 1%, or less than 0.1% by mass or volume of another material. According to various embodiments, a fiber may be said to consist essentially of a given material (e.g., carbon) when the fiber includes less than 5%, less than 1%, or less than 0.01% by mass or volume of another substance.

While various aspects and embodiments are disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for illustrative purposes and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.

Claims

1. An image sensor, comprising:

an absorption layer having an active area configured to generate an electrical signal when the absorption layer absorbs incident X-ray photons;

an electronic device layer extending in a lateral direction parallel to the absorber layer and overlapping an active area of the absorber layer in an inter-layer direction perpendicular to the lateral direction, the electronic device layer configured to receive and process electrical signals from the active area of the absorber layer; and

a printed circuit board comprising at least one conductive layer laminated to at least one non-conductive substrate, the printed circuit board configured to receive processed electrical signals from the electronics layer,

wherein the printed circuit board and the active area of the absorption layer do not overlap in the interlayer direction.

2. The image sensor of claim 1, further comprising:

a support layer that secures the absorbent layer, the electronics layer, and the printed circuit board relative to one another.

3. The image sensor of claim 2, wherein the support layer abuts the electronics layer and the printed circuit board on a side of the electronics layer opposite the absorption layer.

4. The image sensor of claim 2, wherein the support layer abuts the absorption layer and the printed circuit board on a side of the absorption layer opposite the electronics layer.

5. The image sensor of claim 4, wherein the electrical connection between the electronics layer and the printed circuit board comprises a redistribution layer in the absorber layer.

6. The image sensor of claim 2, wherein the support layer has less than or equal to 43cm at 5keV^-1Linear attenuation coefficient of (2).

7. The image sensor of claim 2, wherein the support layer has less than or equal to 20cm at 5keV²Mass attenuation coefficient per gram.

8. The image sensor of claim 2, wherein the support layer consists essentially of a fiber reinforced plastic composite.

9. The image sensor of claim 8, wherein the fibers consist essentially of carbon.

10. The image sensor of claim 1, further comprising:

an electrical connection between the absorber layer and the electronic device layer; and

an electrical connection between the electronics layer and the printed circuit board.

11. The image sensor of claim 10,

the electrical connection between the absorption layer and the electronic device layer comprises a bonding wire, and/or

The electrical connection between the electronic device layer and the printed circuit board includes a bond wire.

12. The image sensor of claim 1, wherein the printed circuit board comprises a flexible cable.

13. The image sensor of claim 1, further comprising at least one via between an electrical contact on the back side of the absorber layer and a circuit element on the front side of the electronics layer.

14. The image sensor of claim 13, further comprising a fill material laterally adjacent to the via between the back surface of the absorber layer and the front surface of the electronics layer.

15. The image sensor of claim 1, wherein the absorption layer forms a diode.

16. The image sensor of claim 1, wherein the absorbing layer forms a resistor.

17. The image sensor of claim 1, wherein the electronics layer forms an Application Specific Integrated Circuit (ASIC).

18. The image sensor of claim 2, wherein the support layer has a thickness of 0.5mm to 2 mm.

19. The image sensor of claim 2, wherein the support layer has a thickness of less than 10 mm.

20. The image sensor of claim 1, wherein the absorbing layer has a thickness of 0.001mm to 1 mm.

21. The image sensor of claim 1, wherein the electronics layer has a thickness of 0.001mm to 1 mm.

22. The image sensor of claim 1, wherein the printed circuit board has a thickness of 0.001mm to 1 mm.

23. A system, comprising:

the image sensor of claim 1; and

at least one of the following:

an X-ray source, or

An electron source.

24. The image sensor of claim 1, wherein the printed circuit board has:

a first portion including a first proximal end and a first distal end extending laterally away from the first proximal end, an

A second portion including a second proximal end and a second distal end extending laterally away from the second proximal end,

said first proximal end and said second proximal end merge at a common portion, and

the first and second distal ends diverge from the common portion to form a concave lateral region between the first and second portions of the printed circuit board.

25. The image sensor of claim 24, further comprising:

a spacer in the concave lateral region.

26. The image sensor of claim 25, wherein the spacer consists essentially of a fiber reinforced plastic composite.

27. The image sensor of claim 26, wherein the fibers consist essentially of carbon.

28. An image sensor, comprising:

a first absorption layer configured to generate a first electrical signal when a first X-ray photon is absorbed therein;

a first electronic device layer configured to receive and process the first electrical signal from the first absorber layer, a front side of the first electronic device layer abutting a back side of the first absorber layer throughout a first active area;

a second absorption layer configured to generate a second electrical signal when a second X-ray photon is absorbed therein;

a second electronic device layer configured to receive and process the second electrical signal from the second absorber layer, a front side of the second electronic device layer abutting a back side of the second absorber layer throughout a second active area;

a printed circuit board configured to receive the processed first electrical signal from the first electronics layer and the processed second electrical signal from the second electronics layer, the printed circuit board having:

a first portion including a first proximal end and a first distal end extending in a transverse plane away from the first proximal end,

a second portion including a second proximal end and a second distal end extending in a transverse plane away from the second proximal end, the first and second proximal ends meeting at a common portion, the first and second distal ends diverging from the common portion to form a concave transverse region between the first and second portions of the printed circuit board,

a front side abutting a back side of the first electronic device layer across a first support margin that overlaps the first portion and the second portion in an interlayer direction perpendicular to the lateral plane, the first electronic device layer extending through the concave lateral region between the first portion and the second portion of the printed circuit board, and

a back side abutting a front side of the second absorbent layer across a second support margin that overlaps the first portion and the second portion in the inter-layer direction, the second absorbent layer extending through the concave lateral region between the first portion and the second portion of the printed circuit board,

wherein the first effective area and the printed circuit board do not overlap in the interlayer direction, and

the second effective area and the printed circuit board do not overlap in the interlayer direction.

29. The image sensor of claim 28, wherein the printed circuit board does not surround at least one lateral line edge of the concave lateral region.

30. The image sensor of claim 28, further comprising:

a spacer in the concave lateral region.

31. A system, comprising:

the image sensor of claim 28; and

at least one of:

an X-ray source, or

An electron source.