Optoelectronic device

Abstract

The invention relates to an optoelectronic device. An optoelectronic device includes a scintillation crystal and a semiconductor die including a first side and a second side opposite the first side. The semiconductor die includes a photomultiplier array disposed on the first side. A scintillation crystal is disposed on a first side of the semiconductor die. The optoelectronic device also includes a carrier disposed on the second side of the semiconductor die. The photomultiplier array is electrically coupled with the carrier. The optoelectronic device also includes a molding material disposed on sidewalls defined by at least one of the semiconductor die and the carrier. The molding material is configured to protect the photomultiplier array from moisture intrusion.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of and priority to U.S. Provisional Application No. 63 / 513,474 filed on July 13, 2023, U.S. Provisional Application No. 63 / 518,443 filed on August 9, 2023, and U.S. Provisional Application No. 63 / 597,748 filed on November 10, 2023, all of which are incorporated herein by reference in their entirety. Technical Field

[0003] The present application relates to a photovoltaic device. Background Art

[0004] Photomultipliers are used in various systems for detecting light (photons), for example, to perform various types of imaging. For example, photomultipliers are used in medical imaging systems, such as positron emission tomography (PET) scanning systems (PET scanners). PET scanners can be used to assess the function and health of a patient's organs and tissues to diagnose a variety of conditions, such as cancer. PET scanners operate by introducing a substance (e.g., a radiopharmaceutical, such as radioactive glucose) into a patient's body, for example, by injection or intravenous infusion. The radiopharmaceutical then interacts with the tissues of the patient's body, causing the emission of gamma (γ) radiation. Diseased tissue (e.g., a malignant tumor (or other disease)) may have a greater interaction (e.g., greater absorption) with the radiopharmaceutical, resulting in a higher level of γ radiation emission than healthy tissue, which facilitates imaging detection of such diseased tissue. For example, γ radiation is detected by one or more crystals (e.g., scintillation crystals) placed near and around at least a portion of the patient. The crystal then converts the detected γ radiation into photons, which can then be detected by a photomultiplier coupled to the crystal. The photomultiplier can then provide an electrical signal corresponding to the photon detection efficiency to an imaging system (e.g., hardware and software), which can then generate a three-dimensional (3D) image of the body based on the detected photons, where the quality of such imaging depends on the efficiency of gamma radiation detection and the detection efficiency of the corresponding photons. Summary of the invention

[0005] In one general aspect, an optoelectronic device includes a first photomultiplier having a first side including a first photodiode array, and a second side opposite the first side. The optoelectronic device also includes a second photomultiplier having a first side including a second photodiode array, and a second side opposite the first side. The second side of the first photomultiplier is directly coupled to the second side of the second photomultiplier in a staggered arrangement.

[0006] In another general aspect, an optoelectronic device includes a scintillation crystal and a semiconductor die, the semiconductor die including a first side and a second side opposite the first side. The semiconductor die includes a photomultiplier array disposed on the first side. The scintillation crystal is disposed on the first side of the semiconductor die. The optoelectronic device also includes a carrier disposed on the second side of the semiconductor die. The photomultiplier array is electrically coupled to the carrier. The optoelectronic device also includes a molding material disposed on a sidewall defined by at least one of the semiconductor die and the carrier. The molding material is configured to protect the photomultiplier array from moisture intrusion.

[0007] In another general aspect, an optoelectronic device includes a first semiconductor die and a second semiconductor die, the first semiconductor die including a first photomultiplier array, the second semiconductor die including a second photomultiplier array. The second semiconductor die is coupled to the first semiconductor die in a stacked manner, such that the first photomultiplier array is disposed at a proximal end of the stack, and the second photomultiplier array is disposed at a distal end of the stack. The optoelectronic device also includes a first scintillation crystal and a second scintillation crystal, the first scintillation crystal being disposed on the first semiconductor die at the proximal end of the stack, and the second scintillation crystal being disposed on the second semiconductor die at the distal end of the stack. The stack is disposed between the first scintillation crystal and the second scintillation crystal. The optoelectronic device also includes an encapsulation material, the encapsulation material being disposed on a sidewall defined by the first semiconductor die and the second semiconductor die, and between the first scintillation crystal and the second scintillation crystal.

[0008] In another general aspect, an optoelectronic device includes a scintillation crystal, a first photomultiplier, and a second photomultiplier. The first photomultiplier is disposed on a first side wall of the scintillation crystal, and the second photomultiplier is disposed on a second side wall of the scintillation crystal. The second side wall is orthogonal to the first side wall. The optoelectronic device also includes a third photomultiplier disposed on a third side wall of the scintillation crystal, and the third side wall is parallel to the first side wall. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1A is a diagram showing an exemplary photomultiplier and scintillation crystal assembly.

[0010] Figure 1B and Figure 1C are shown separately Figure 1A Schematic diagram of exemplary conductive signal traces of an assembly of a photomultiplier.

[0011] Figure 2 is a diagram illustrating another exemplary photomultiplier and scintillation crystal assembly.

[0012] FIG. 3A to FIG. 3D is shown for generating a Figure 2Schematic diagram of an exemplary process for assembly of back-to-back photomultipliers.

[0013] Figure 4 is a diagram illustrating another exemplary photomultiplier and scintillation crystal assembly.

[0014] FIG. 5A to FIG. 5E is shown for generating a Figure 4 Schematic diagram of an exemplary process for assembly of back-to-back photomultipliers.

[0015] FIG. 6A to FIG. 6C is shown for generating a Figure 4 Schematic diagram of another exemplary process for assembly of back-to-back photomultipliers.

[0016] Fig. 7A and Figure 7B is a diagram illustrating an exemplary photomultiplier.

[0017] Figure 7C is a diagram showing a plurality of photomultipliers (eg, Fig. 7A and Figure 7B Schematic diagram of an exemplary chip with a photomultiplier.

[0018] FIG. 8A to FIG. 8D is shown for generating a Fig. 7A and Figure 7B FIG. 1 is a diagram of an exemplary process for assembly of a photomultiplier and scintillation crystal of a photomultiplier.

[0019] Fig. 8E and Fig.8F It shows that you can use FIG. 8A to FIG. 8D An illustration of an example of an alternative structure produced by the process.

[0020] Fig. 9 is shown including back-to-back photomultipliers (e.g., Fig. 7A and Figure 7B Schematic diagram of an exemplary photomultiplier and scintillation crystal assembly of a photomultiplier.

[0021] Fig. 10A is a diagram illustrating an exemplary single-sided photomultiplier.

[0022] Fig. 10B It is shown that Fig. 10A Schematic diagram of an exemplary photomultiplier and scintillation crystal assembly of a single-sided photomultiplier.

[0023] FIG. 11A to FIG. 11C is shown for generating Fig. 10B Figure 2 is a diagram of an exemplary process for photomultiplier and scintillation crystal assembly.

[0024] Fig. 12Ais a diagram showing another exemplary single-sided photomultiplier.

[0025] Fig. 12B It is shown that Fig. 12A Schematic diagram of an exemplary photomultiplier and scintillation crystal assembly of a photomultiplier.

[0026] Fig.13A and Fig. 13B is a diagram illustrating another exemplary photomultiplier and scintillation crystal assembly.

[0027] Fig.14 It is shown that the FIG. 3A to FIG. 3D A flowchart of an exemplary method of the process.

[0028] Fig.15 It is shown that the FIG. 5A to FIG. 5E A flowchart of an exemplary method of the process.

[0029] Fig.16 It is shown that the FIG. 6A to FIG. 6C A flowchart of an exemplary method of the process.

[0030] Fig.17 It is shown that the FIG. 8A to FIG. 8D A flowchart of an exemplary method of the process.

[0031] Fig.18 It is shown that the FIG. 11A to FIG. 11C A flowchart of an exemplary method of the process.

[0032] Fig.19 is shown for generating Fig. 12B Flow chart of an exemplary method of photomultiplier and scintillation crystal assembly.

[0033] In the drawings that are not necessarily drawn to scale, the same reference numerals may indicate the same and / or similar parts (elements, structures, etc.) in different views. The drawings generally illustrate various implementations discussed in the present disclosure by way of example rather than by way of limitation. Reference numerals shown in one drawing may not be repeated for the same and / or similar elements in the related views. Reference numerals repeated in multiple drawings may not be specifically discussed for each of those drawings, but are provided for the context between the related views. In addition, when multiple instances of an element are shown, all similar elements in the drawings are not specifically referred to by reference numerals. DETAILED DESCRIPTION

[0034] The present disclosure relates to devices and components that can be used in imaging systems. For example, an exemplary component or module (imaging system module) including a photomultiplier device (e.g., a silicon photomultiplier (SiPM)) and a scintillator crystal is described herein. Although the exemplary implementations are generally described for components or modules used in a positron emission tomography (PET) scanning system including a SiPM, in some implementations, the devices, methods, and techniques described herein can be used in components or modules of other types of imaging systems, can be made using different semiconductor materials, and / or can be applied to imaging systems other than PET scanners (e.g., computed tomography (CT) systems), etc.

[0035] At least one technical problem associated with existing implementations of components and / or modules for, for example, PET scanners is a limitation on the detection efficiency of both detecting emitted gamma radiation, for example, by scintillation crystals, and detecting photons generated by gamma radiation that interact with (intersect, collide with, etc.) scintillation crystals in a scanning system. Such limitations on the detection efficiency of gamma radiation emitted from a patient's body during a PET scan may be due, at least in part, to spacing (gaps) between scintillation crystals, where, as some examples, such gaps are used to implement photomultiplier devices, printed circuit boards (PCBs) interconnecting the photomultiplier devices, and / or electrical connectors for providing electrical signals resulting from photon detection to external circuits, for example, for image processing. Limitations on photon detection efficiency may be due to locations selected for placement of photomultipliers, for example, so as not to increase gaps between scintillation crystals, where such placement is limited in existing implementations.

[0036] Another technical problem associated with existing approaches is sensitivity to moisture intrusion, which can lead to various reliability issues such as component swelling of the assembly, degradation (corrosion) of electrical contacts or vias (eg, vias formed through the semiconductor die of a SiPM).

[0037] Another technical problem with existing methods is the limitation on reducing the coincidence resolution time (CRT), which is at least partially due to detection efficiency. For example, in a PET scanning system, a radionuclide is introduced into the body. Positrons are emitted by the decomposition of the radionuclide in the organs and / or tissues of the body. Gamma rays, which may be referred to as annihilation photons, are produced when those emitted positrons collide with electrons near the decay event. The PET scanner then detects the gamma radiation (annihilation photons), which arrive at the detector 180 degrees apart and coincidentally, thereby generating photons (e.g., light with a wavelength of 420 nanometers), which are detected by corresponding photomultipliers. The CRT is the timing accuracy of the gamma radiation detection (and corresponding photon detection) on opposite sides of the PET scanner detector array. Limitations on existing implementations for improving detection efficiency (gamma radiation and / or generated photons) limit improvements to the CRT.

[0038] A technical solution to at least some of the technical problems mentioned above may be to use back-to-back photomultipliers, or to use single-sided photomultipliers. One technical effect of this solution is that it is possible to exclude components included in existing devices and components. A benefit of this technical effect may be to improve the gamma radiation detection efficiency, because the gap between the scintillation crystals may be reduced due to the elimination of components between the crystals (for example, the elimination (removal) of the PCB between the crystals). Another benefit of this technical solution may be to improve the photon detection efficiency, because compared with the existing methods, additional photomultipliers may be included in an imaging system module (multiple imaging system modules, modules, etc.) including the scintillation crystals and the photomultipliers, but the gap between the scintillation crystals will not be significantly increased. That is, the resulting increase in photon efficiency may more than offset any effect on the gamma radiation detection efficiency. Another benefit of this technical effect is the improved (reduced) CRT provided by the improved gamma radiation and / or photon detection.

[0039] Another technical solution to at least some of the aforementioned technical problems is, for example, to use a water vapor intrusion-proof material on the side walls of a photomultiplier device in an imaging system module. The technical effect of this technical solution may be to protect the active surface of the photomultiplier semiconductor die (e.g., photodiode array, through silicon via, etc.) from water vapor intrusion. One benefit of this technical effect may be to avoid reliability issues associated with water vapor. Another technical effect of this technical solution is that a glass component (cover) partially used to prevent water vapor intrusion can be excluded or removed. One benefit of this technical effect may be to further reduce the gap size between scintillation crystals, which may further improve the positron detection efficiency.

[0040] For illustrative purposes, in some cases, exemplary implementations described herein are schematically shown in the accompanying drawings, which may be side views and / or cross-sectional views. Such cross-sectional views are shown to at least partially show structural elements of the described implementations, where such structures may be obscured, for example, by packaging materials or other elements in non-cross-sectional views.

[0041] Figure 1A 1 is a diagram illustrating an exemplary photomultiplier and scintillation crystal assembly (assembly 100) that can be used in an imaging system (e.g., a PET scanner). Assembly 100 includes a plurality of photomultipliers, e.g., photomultiplier 110 and photomultiplier 120. Photomultipliers 110 and 120 are arranged in a back-to-back staggered configuration. In this example, photomultipliers 110 each include a photomultiplier die 110a and a glass component 110b (cover), while photomultipliers 120 each include a photomultiplier die 120a and a glass component 120b (cover). Electrical signals generated by the photodiode arrays of photomultiplier die 110a and photomultiplier die 120a can be conducted to a backside surface opposite to a corresponding side of the photomultiplier die including the photodiode array using a through hole (e.g., a through silicon via (TSV)). Those signals can then be connected using conductive traces (copper traces) disposed on the backside of the photomultiplier dies 110a and 120a (e.g., Figure 1B and Figure 1C 1 and 120 to external circuitry. Thus, the PCB is not used to provide signal communication of electrical signals generated by photomultipliers 110 and 120 to external circuitry. In other words, the back-to-back staggered arrangement of photomultipliers 110 and 120 precludes a PCB from being used to communicate electrical signals generated by corresponding photodiode arrays that indicate photon detection.

[0042] like Figure 1A As shown, assembly 100 includes scintillation crystals 140, which are coupled to the sides of photomultipliers 110 and 120 including corresponding photodiode arrays, respectively. In some implementations, scintillation crystals 140 can be coupled to photomultipliers 110 and 120 using an optically clear silicone adhesive to limit photon losses due to the interface between scintillation crystals 140 and glass components 110b and 120b of photomultipliers 110 and 120.

[0043] In this example, photomultipliers 110 and 120 are Figure 1AThe arrangement shown uses solder balls 130 for coupling, wherein the solder balls 130 of one photomultiplier can be coupled to the landing pads of the conductive traces on another back-to-back staggered photomultiplier. In some implementations, the photomultipliers 110 and 120 can be coupled in such a back-to-back staggered configuration by wafer-to-wafer bonding of two complementary wafers, which can provide an additional reduction in the size of the gap between the scintillation crystals 140. In this example, the photomultiplier 120 is larger than the photomultiplier 110, which enables the sidewalls of the two scintillation crystals 140 to be covered (e.g., completely covered) by the back-to-back staggered arrangement of the photomultipliers 110 and 120.

[0044] Figure 1B and Figure 1C are shown separately Figure 1A 1 is a diagram of exemplary conductive signal traces of the photomultipliers 110 and 120 of the assembly 100. For example, Figure 1B Conductive traces of photomultiplier 110 are shown. The conductive traces of photomultiplier 110 include conductive trace 112 including pads 112a and 112b, conductive trace 114 including pads 114a and 114b, conductive trace 116 including pads 116a and 116b, and conductive trace 118 including pads 118a and 118b. In this example, conductive trace 112 may conduct electrical signals for anodes of a photodiode array of photomultiplier 110, while conductive trace 114 may conduct electrical signals for cathodes of a photodiode array of photomultiplier 110. In this example, as described herein, conductive traces 112 and conductive traces 114 can be coupled to the photodiode array of photomultiplier 110 using through holes formed through the photomultiplier die 110a of photomultiplier 110, for example, from the front side (photodiode array side) of photomultiplier die 110a to the back side (conductive trace side) of photomultiplier die 110a.

[0045] In this example, conductive traces 116 and 118 are pass-through conductive traces for conducting electrical signals for the anode and cathode of other photomultipliers, such as those in Figure 1A The photomultiplier die 110a of the photomultiplier 110 is electrically coupled in a back-to-back staggered arrangement. The pads 112a, 112b, 114a, 114b, 116a, 116b, 118a, and 118b can be used for electrical connection between back-to-back photomultipliers, and / or for connection between, for example, the photomultipliers 110 and 120 of the assembly 100 and external circuits, for example, for image processing. In some implementations, a flexible connector, a PCB, or other methods can be used to implement electrical connection with external circuits.

[0046] Similar to Figure 1B The photomultiplier 110 shown, Figure 1C Shows Figure 1A Conductive traces of a photomultiplier 120 of the assembly 100 are shown. The conductive traces of the photomultiplier 120 include conductive trace 122, conductive trace 124, conductive trace 126, and conductive trace 128. In this example, conductive trace 122 can conduct electrical signals for an anode of a photodiode array of the photomultiplier 120, while conductive trace 124 can conduct electrical signals for a cathode of a photodiode array of the photomultiplier 120. In this example, conductive trace 122 and conductive trace 124 can be coupled to the photodiode array of the photomultiplier 120 using vias, as described herein, formed through the photomultiplier die 120a of the photomultiplier 120, for example, from the front side (photodiode array side) of the photomultiplier die 120a to the back side (conductive trace side) of the photomultiplier die 120a.

[0047] In this example, conductive traces 126 and 128 are through conductive traces for conducting electrical signals for the anode and cathode of other photomultipliers, such as Figure 1A The back-to-back staggered arrangement is electrically coupled to the photomultiplier die 120a of the photomultiplier 120. Figure 1C Not explicitly mentioned in, but related to Figure 1B Like the conductive traces of photomultiplier 110 in the assembly 100, conductive traces 122, 124, 126, and 128 include corresponding pads that can be used for electrical connection between back-to-back photomultipliers and / or for connection of photomultipliers 110 and 120 of assembly 100 to external circuitry for image processing, for example.

[0048] By way of example Figure 1B and Figure 1C The conductive trace arrangement shown. In some implementations, other arrangements may exist. For example, additional conductive traces may be used, conductive traces with different layouts may be used, and so on.

[0049] Figure 2 2 is a diagram illustrating another exemplary photomultiplier and scintillation crystal assembly (assembly 200). Figure 2 As shown, the assembly 200 includes Figure 1A Component 100. Figure 2 The assembly 200 in the example also includes another back-to-back staggered arrangement of photomultipliers located to the right of the assembly 100, which is coupled to the assembly 100 and another scintillation crystal 240, thereby reproducing the structure of the assembly 100.

[0050] The assembly 200 also includes corresponding columns of individual photomultipliers, one column on the right side of the assembly 200 and one column on the left side of the assembly 200, each of which includes two photomultipliers 110 and one photomultiplier 120. The assembly 200 also includes corresponding individual photomultipliers coupled to the bottom of the scintillation crystals of the assembly 200. In this example, a back-to-back photomultiplier arrangement is not used on the left and right sides of the assembly 200 (or at the bottom of the scintillation crystals of the assembly 200) because there are no corresponding scintillation crystals to generate photons for detection by the additional back-to-back photomultipliers.

[0051] The assembly 200 also includes PCBs located on the left side, right side, and bottom of the assembly 200, which can provide signal communication between corresponding photomultipliers. In addition, the assembly 200 includes a plurality of flexible connectors that can connect the photomultipliers of the assembly 200 to external (e.g., image processing) circuits. The assembly 200 is configured to receive positron emission in a PET scanner located at the top of the assembly 200, wherein the upper side wall of the scintillator is exposed. In some implementations, the structure of the assembly 200 can be expanded by including a back-to-back staggered arrangement of additional photomultipliers and additional corresponding scintillator crystals.

[0052] FIG. 3A to FIG. 3D is shown for generating a Figure 1A The component 100 and / or Figure 2 FIG. 2 is a diagram of an exemplary process for a back-to-back photomultiplier structure in an assembly 200 of FIG. 2. Therefore, for the purpose of illustration, FIG. 3A to FIG. 3D The process is described as including elements of assembly 100 and / or elements of assembly 200 .

[0053] like Figure 3A As shown, a single photomultiplier 120 and two of the photomultipliers 110 are arranged on (coupled with) a carrier 305, which may be a rigid temporary carrier such as glass. In this example, two such photomultiplier arrangements may be produced to produce a back-to-back staggered arrangement of photomultipliers. Figure 3B As shown, the flexible connector 260 is connected to Figure 3A The structure of the photomultiplier 120 is coupled to produce the structure 300 .

[0054] like Figure 3C As shown, Figure 3B Structure 300 of FIG. 1 may be coupled (welded, etc.) to structure 300 a , which is similar to structure 300 , except that flexible connector 260 is coupled to one of photomultipliers 110 instead of photomultiplier 120 .

[0055] like Figure 3DAs shown, after coupling structure 300 to structure 300a, the respective carriers 305 of structure 300 and structure 300a can be removed. In some implementations, ultraviolet light can be used to release the adhesive used to couple carrier 305 to their respective photomultipliers. In other implementations, heat can be moved to release the adhesive used to couple carrier 305 to their respective photomultipliers. After removing carrier 305 from structure 300 and structure 300a, respectively, the resulting Figure 3D The back-to-back staggered arrangement of photomultipliers 110 and 120 may be coupled with a scintillation crystal and included in an imaging system assembly (eg, assembly 100 or assembly 200), but Figure 3D The structure may be included in assemblies having other configurations.

[0056] Figure 4 is a diagram illustrating another exemplary photomultiplier and scintillation crystal assembly (assembly). Figure 4 The assembly includes a module 400, which includes a back-to-back staggered arrangement of photomultipliers 410 and 420. Figure 2 Components 200, Figure 4 The assembly also includes a PCB 450 and a flexible connector 460 . Figure 4 Components and Figure 2 The assembly 200 of FIG. 1 is different in that the photomultipliers (e.g., photomultipliers 410, 420 and other photomultipliers, such as those coupled to the bottom sidewall of the scintillation crystal) do not include a glass cover or component. Such an implementation can be advantageous because it is similar to Figure 2 Compared to the assembly 200 of FIG. 2 , such an implementation can further reduce the gap between the scintillation crystals from the gap between the crystals in the existing implementation where the PCB is included in the photomultiplier stack. For example, in some implementations, the back-to-back stack of photomultipliers 110 can have a total thickness of less than 150 micrometers (μm), and each glass component (cover) can have a thickness of 400 μm. Therefore, without including the glass components, the total thickness of the back-to-back arrangement of the photomultipliers can be reduced from a thickness of approximately 0.95 millimeters (mm) to a thickness of less than 150 μm, which is a reduction of more than 84%, and can improve the positron detection efficiency.

[0057] FIG. 5A to FIG. 5E is shown for generating a method that can be included in e.g. Figure 4 Schematic diagram of an exemplary process for back-to-back photomultipliers in an assembly of. In some implementations, FIG. 5A to FIG. 5E The process can be combined FIG. 3A to FIG. 3C For example, you can use FIG. 3A to FIG. 3C The operations shown produce a structure that performs FIG. 5A to FIG. 5ETherefore, for the sake of brevity, we will not discuss FIG. 5A to FIG. 5E The details of those operations are discussed in detail in the FIG. 5A to FIG. 5E In the discussion of FIG. 3A to FIG. 3C The 100 series reference numerals used in the drawings are replaced with corresponding 400 series reference numerals, and the FIG. 3A to FIG. 3C The 300 series reference numerals used in the drawings are replaced with 500 series reference numerals.

[0058] like Figure 5A As shown, Figure 3C The carrier substrate and glass component (cover) are removed from one side of the structure. In some implementations, a thermal operation can be used to release the glass component from its corresponding photomultiplier. In this example, the adhesive used to couple the carrier to the glass component can be a high temperature adhesive having a higher release temperature than the adhesive used to couple the glass component to the semiconductor die of the corresponding photomultipliers 410 and 420, so that the carrier and the glass component can be removed simultaneously.

[0059] like Figure 5B As shown, carrier 507 (temporary carrier) is Figure 5A The exposed photomultiplier semiconductor die is shown coupled in operation. In an exemplary implementation, carrier 507 can be coupled to the photomultiplier semiconductor die using an adhesive that can be released using ultraviolet light and / or heat.

[0060] Then, if Figure 5C As shown, for example, using ultraviolet light and / or heat, from Figure 5B The glass components 410b and 420b are removed from the second (bottom) side of the structure, along with the carrier 505. Figure 5D As shown, Figure 5C The photomultiplier on the second (bottom) side of the structure can be coupled to the scintillator crystal 540, for example using an optically clear silicone adhesive, to produce the structure 500, and the carrier 507 can be removed, for example using ultraviolet light. Figure 5E As shown, Figure 5D The structure 500 can be coupled to another structure 500. In an exemplary implementation, the Figure 5E The structure shown is used to produce imaging system modules, such as Figure 4 Module 400.

[0061] FIG. 6A to FIG. 6C is shown for generating a method that can be included in e.g. Figure 4 Schematic diagram of another exemplary process for assembly of back-to-back photomultipliers. FIG. 6A to FIG. 6C The process can be combined with FIG. 5C to FIG. 5E The operations are performed similarly to those shown, with one difference being that carrier 507 (temporary carrier) is not used. FIG. 6A to FIG. 6B The process can provide structural and mechanical stability to the photomultiplier die. Since such semiconductor dies can be ground to a thickness of less than 100 μm, removing the corresponding glass cover significantly increases the likelihood of handling and / or shipping damage (eg, cracking). FIG. 6A to FIG. 6C The process provides additional stability and allows the corresponding glass cover to be removed without using a temporary carrier and without significantly increasing the risk of damage.

[0062] Although not in FIG. 6A to FIG. 6C , but the flexible connector can be coupled to the corresponding photomultiplier in the unseparated photomultiplier group. Fig. 6A As shown, in some implementations, a partial sawing or laser cutting operation can be performed to form an opening 615 between photomultipliers 610 and 620 in structure 600, and a flexible connector can be coupled to a photomultiplier (610 or 620) of structure 600. In some implementations, a photomultiplier group (e.g., Figure 6B The structure shown) can be used to produce a back-to-back staggered arrangement of photomultipliers.

[0063] like Figure 6C As shown, two structures 600 are coupled in a back-to-back configuration. In this example, the corresponding flexible connectors can be connected to Figure 6C The leftmost photomultiplier in each of the top and bottom structures 600 is shown coupled. After performing a cutting operation (e.g., laser sawing) to completely separate the photomultipliers 610 and 620, the photomultipliers 610 and 620 can be used to FIG. 5C to FIG. 5E Similar operations are shown for further processing Figure 6C structure to produce a structure that can be used in imaging system modules (e.g., Figure 4 400) used in the structure (e.g., Figure 5E structure).

[0064] Fig. 7A and Figure 7B is a diagram showing an exemplary photomultiplier 710. Fig. 7A As shown, the photomultiplier 710 includes a plurality of photomultiplier pixels 720 (micro-units) (an array of photomultiplier pixels 720 (micro-units), etc.). In this example, each photomultiplier pixel 720 of the photomultiplier 710 has a height h, where h can be set to establish a desired timing performance (e.g., consistent with a resolution time) for the photomultiplier 710 in a given imaging system. Each photomultiplier pixel 720 of the photomultiplier 710 (or other photomultipliers, such as those described herein) can include a plurality of avalanche photodiodes.

[0065] The propagation time of the signal in the photomultiplier (e.g., the transit time from the photomultiplier pixel 720 to the corresponding output contact pad) depends on h and the number of photomultiplier pixels 720. By the implementation described herein, facilitating decreasing h and increasing the number of pixels will reduce the signal propagation time, thus improving the CRT.

[0066] In the photomultiplier 710 ( Fig. 7A ) can be used to connect the photomultiplier pixels 720 of the photodiode array to the bus 730 and contact pads 735 located on the back side of the photomultiplier 710, wherein the corresponding through holes having bonding pads 725a on the front side (photodiode array side) of the photomultiplier pixel 720 can be used to connect the bus 730 and contact pads 735 located on the back side of the photomultiplier 710. Figure 7B , through-hole 725b is shown on the back side of photomultiplier 710. In some implementations, a flexible connector can be electrically coupled to contact pad 735 to connect photomultiplier 710 to an external circuit, or contact pad 735 can be electrically coupled to a carrier using wire bonding. Figure 7B As shown, the back side of the photomultiplier 710 may also include electrically floating contact pads 740 for connecting the photomultiplier 710 to a rigid carrier or substrate (eg, a PCB or a complementary wafer), as described below.

[0067] Figure 7C is a diagram showing a plurality of photomultipliers (eg, Fig. 7A and Figure 7B 700). In some implementations, wafer 700 can be coupled to another wafer, such as another wafer 700, a passive wafer, or a wafer having devices other than photomultiplier 710. The two wafers can be coupled using wafer-to-wafer bonding, which can produce a back-to-back photomultiplier arrangement (staggered or not) that can be included in an imaging system assembly formed of modules such as those described herein.

[0068] FIG. 8A to FIG. 8D is shown for generating a Fig. 7A and Figure 7B FIG. 7 is a diagram of an exemplary process for photomultiplier and scintillation crystal assembly of a photomultiplier 710. Fig. 8A As shown, the photomultiplier 710 can be coupled to a carrier 850 (e.g., a rigid PCB). In this example, the photomultiplier 710 includes a photomultiplier die 710a and a glass member 710b (cover). The carrier 850 can include electrical contact pads to which through-holes of the photomultiplier die 710a electrically coupled to the photodiode array of the photomultiplier 710 can be bonded (e.g., using wafer-to-wafer bonding) or soldered (e.g., by solder balls).

[0069] like Figure 8B As shown, the glass cover 710b can be removed from the photomultiplier die 710a, for example using UV light and / or heat. Figure 8C As shown, the photomultiplier die 710a and the carrier 850 may be coupled with the scintillation crystal 840. In this example, the area of ​​the stack including the photomultiplier die 710a and the carrier 850 may be smaller than the area of ​​the corresponding sidewall of the scintillation crystal 840 to which the stack is coupled.

[0070] Further Figure 8C As shown, the water vapor intrusion-proof material 880 may be formed on the sidewalls defined by the photomultiplier die 710a and the carrier 850, and on the sidewalls of the scintillation crystal (840) on which the Figure 8B The moisture-proof material 880 may be an epoxy, silicone, or other such material. The moisture-proof material 880 may be disposed (molded, formed, etc.) at least partially around the periphery of the sidewalls defined by the photomultiplier die 710a and the carrier 850, and may prevent or reduce moisture intrusion into the interface between the photomultiplier die 710a and the carrier 850. Such moisture intrusion may lead to reliability issues, such as failure of a through hole formed in the photomultiplier die 710a. Therefore, reducing or preventing such intrusion may improve reliability relative to existing implementations.

[0071] Also like Figure 8C As shown, flexible connector 860 can be coupled to carrier 850. Flexible connector 860 can be used to connect the photodiode array of photomultiplier die 710a to external circuitry, for example, in conjunction with vias formed through carrier 850, signal traces (e.g., signal buses) included in carrier 850 and / or photomultiplier die 710a, and / or vias formed in photomultiplier die 710a. Then, the photomultiplier die 710a can be connected to the carrier 850 using a flexible connector 860. Figure 8C The structure of the imaging system module is generated. For example, Figure 8C The structure of can be included in exemplary imaging system modules, such as those imaging system modules described herein (e.g., assembly 200, module 400, and modules having other configurations).

[0072] Fig.8D yes Figure 8C The top view of the structure. Fig.8D As shown, the waterproof vapor intrusion material 880 at least partially surrounds the photomultiplier tube core 710a (in Fig.8D 850) and the stacked periphery of the carrier 850. Fig.8D As shown, the flexible connector 860 is located at Fig.8D The top surface of the structure ( Figure 8Ctop of view) coupled to a carrier 850.

[0073] Fig. 8E and Fig.8F It shows that you can use FIG. 8A to FIG. 8D An illustration of an example of an alternative structure produced by the process. Fig. 8E and Fig.8F The structure is similar to Figure 8C The difference is related to the shape and / or side of the carrier. Figure 8C Compared with the carrier 850, Fig. 8E In the example, the carrier 850a is partially etched (e.g., half-etched) around the periphery of the carrier 850a. Thus, in this example, the water vapor intrusion prevention material 880 extends onto (over, etc.) the partially etched area. Fig.8F In the example of FIG. 7 , the area (occupied area, etc.) of the carrier 850b is smaller than the sidewall of the scintillator crystal 840 on which the carrier 850 is disposed. Thus, the water vapor intrusion resistant material 880 extends over a portion, such as a peripheral portion of the backside surface of the photomultiplier die 710a. For example, a portion of the conductive traces located on the backside of the die may be encapsulated in the water vapor intrusion resistant material 880.

[0074] Fig. 9 is shown including back-to-back photomultipliers (e.g., Fig. 7A and Figure 7B Schematic diagram of an exemplary photomultiplier and scintillation crystal assembly. Fig. 9 As shown, photomultiplier 710p is coupled back-to-back with photomultiplier 710d, and each of photomultipliers 710p and 710d is coupled to a corresponding flexible connector (via contact pads 735) and to a corresponding scintillation crystal 940 (e.g., located on the photodiode array side of photomultiplier 710). Fig. 9 The upper photomultiplier in Fig. 9 The photodiode array of photomultiplier 710p may be referred to as being disposed (positioned, etc.) at the proximal end of the stack formed by photomultiplier 710p and photomultiplier 710d. In this example, photomultiplier 710d ( Fig. 9 The lower photomultiplier in Fig. 9 The photodiode array of photomultiplier 710d may be referred to as being disposed (positioned, etc.) at the distal end of the stack formed by photomultiplier 710p and photomultiplier 710d.

[0075] like Fig. 9As shown, the corresponding scintillator crystal 940 is larger than the photomultipliers 710p and 710d. That is, the surface area of ​​the corresponding scintillator crystal 940 coupled to the photomultipliers 710p and 710d is larger than the corresponding surface area of ​​the photomultipliers 710p and 710d. In this example, the water vapor intrusion prevention material 980 is arranged around the back-to-back arrangement of the photomultipliers 710p and 710d and is arranged, for example, Fig. 9 9 and 90 are shown between respective scintillator crystals 940. As discussed herein, water vapor intrusion resistant material 980 again provides protection to photomultipliers 710p and 710d against water vapor intrusion, which can help prevent reliability issues associated with water vapor.

[0076] Fig. 10A 1 is a diagram illustrating an exemplary single-sided photomultiplier assembly 1000. The use of a single-sided photomultiplier (e.g., photomultiplier die 1010) precludes the use of through-vias (e.g., TSVs). Thus, implementations including such single-sided photomultiplier die 1010 can prevent moisture-related reliability issues associated with at least through-vias.

[0077] like Fig. 10A As shown, a photomultiplier 1010 including a plurality of photomultiplier pixels 1020 is disposed on a carrier 1050 (e.g., a rigid carrier such as a PCB). The photomultiplier die 1010 includes a bus 1030 located on the front side of the photomultiplier die 1010 (e.g., the same side as the photodiode array). The bus 1030 connects the plurality of photomultiplier pixels 1020 to contact pads 1015, respectively. The contact pads are then electrically coupled to contact pads 1055 of the carrier 1050 via corresponding wire bonds 1057.

[0078] like Fig. 10B As shown, the single-sided photomultiplier assembly 1000 is coupled to a scintillation crystal 1040 in an offset arrangement. A moisture-proof material 1080 is applied to the sidewalls defined by the photomultiplier die 1010 and the scintillation crystal 1040. Fig. 10A In this example, a moisture-proof material 1080 is also applied (molded, etc.) to encapsulate the wire bonds 1057. Fig. 10BAs shown, in this example, a portion of the water vapor intrusion material is disposed on the surface of the carrier 1050 coupled to the wire bonds, and on a portion of the sidewalls of the carrier and the sidewalls of the scintillation crystal 1040 (e.g., the sidewalls of the attached wire bonds). The water vapor intrusion material 1080 may be an epoxy, silicone, or other such material. The water vapor intrusion material 1080 may prevent or reduce water vapor intrusion into the interface between the photomultiplier die 1010 and the carrier 1050 and the interface between the photomultiplier die 1010 and the scintillation crystal 1040, which may reduce or prevent associated reliability issues.

[0079] FIG. 11A to FIG. 11C is shown for generating Fig. 10B 1010 . Fig.11A As shown, in this example, the photomultiplier die 1010 is coupled to a carrier 1050 (e.g., a rigid PCB). The carrier 1050 may include electrical contact pads 1055, and the photomultiplier die 1010 is electrically coupled to the electrical contact pads 1055 via wire bonds 1057 (e.g., leading to pads 1015 of the photomultiplier die 1010). In this example, the photomultiplier 1010 does not include a glass component or cover. However, in some implementations, Fig.11A The operation may include removing the glass component (if present) from the photomultiplier die.

[0080] like Fig. 11B As shown, wire bonds 1057 are formed to electrically connect the photomultiplier die 1010 to the carrier 1050. Fig. 11B As shown, the stack including the photomultiplier die 1010 and the carrier 1050 is coupled to the scintillation crystal 1040. Fig. 10B In an example of , a stack including photomultiplier dies 1010 and carrier 1050 may have a staggered arrangement with scintillation crystals 1040 .

[0081] like Fig. 11C As shown, a moisture-proof material 1080 is applied to the sidewalls defined by the photomultiplier die 1010 and the scintillation crystal 1040. Fig.11A In this example, a moisture-proof material 1080 is also applied (molded, etc.) to encapsulate the wire bonds 1057. Fig. 11CAs shown, in this example, a portion of the water vapor intrusion material is disposed on the surface of the carrier 1050 coupled to the wire bonds, and on a portion of the sidewalls of the scintillation crystal 1040 (e.g., the sidewalls of the attached wire bonds). The water vapor intrusion material 1080 may be an epoxy, silicone, or other such material. The water vapor intrusion material 1080 may prevent or reduce the intrusion of water vapor into the interface between the photomultiplier die 1010 and the carrier 1050, which may reduce or prevent associated reliability issues.

[0082] Although not in FIG. 11A to FIG. 11C 1050, but the flexible connector can be coupled to the carrier 1050. The flexible connector can be used to connect the photodiode array of the photomultiplier die 1010 to external circuitry, for example, in conjunction with vias formed through the carrier 1050, signal traces (e.g., signal buses) included in the carrier 1050 and / or the photomultiplier die 1010, and / or wire bonds 1057. This structure can then be used to create an imaging system module. For example, by FIG. 11A to FIG. 11C The structure produced by the process of can be included in an exemplary imaging system module, such as those imaging system modules described herein (e.g., assembly 200, module 400, and modules having other configurations).

[0083] Fig. 12A 1 is a diagram showing an exemplary single-sided photomultiplier 1210. Fig. 12A As shown, the photomultiplier 1210 includes a plurality of photomultiplier pixels 1220. The photomultiplier die 1210 includes a bus 1230 located on the front side (e.g., the same side as the photodiode array) of the photomultiplier die 1210. The bus 1230 connects the plurality of photomultiplier pixels 1220 to contact pads 1215, respectively, which may include solder balls or anisotropic conductive film (ACF) contacts.

[0084] Fig. 12B It is shown that Fig. 12A 12 is a diagram of an exemplary photomultiplier and scintillation crystal assembly 1200 of a photomultiplier 1210. Fig. 12BAs shown, the corresponding PCB 1260 is coupled to, for example, the contact pads 1215 of the back-to-back photomultiplier die 1210. The PCB 1260 can be coupled to the photomultiplier die using solder (e.g., solder balls), ACF, or other methods. The photomultiplier and scintillation crystal assembly 1200 also includes a corresponding scintillation crystal 1240 coupled to the back-to-back photomultiplier die 1210. A water vapor intrusion resistant material 1280 (epoxy, silicone, etc.) is applied, disposed, molded, etc., such that the water vapor intrusion resistant material 1280 contacts (covers) the sidewalls defined by the stack of back-to-back photomultipliers 1210, contacts at least a portion of one or more sidewalls of the scintillation crystal 1240, and partially encapsulates the PCB 1260, wherein multiple portions of the PCB 1260 extend beyond the water vapor intrusion resistant material 1280 and are located outside the water vapor intrusion resistant material 1280, such as Fig. 12B shown.

[0085] Fig.13A and Fig. 13B is a diagram illustrating an example of a photomultiplier and scintillation crystal assembly 1300 . Fig.13A is a side view of a photomultiplier and scintillation crystal assembly 1300, Fig. 13B is a side cross-sectional view of a photomultiplier and scintillation crystal assembly 1300 . Fig.13A and Fig. 13B The photomultiplier and scintillation crystal assembly 1300 includes a single scintillation crystal 1340, which may be in the form of a block (e.g., a rectangular cube, a rectangular block, etc.), respectively, so that one or more photomultipliers are arranged on each of the multiple sides of the scintillation crystal 1340. For example, in this example, the photomultiplier and scintillation crystal assembly 1300 may have photomultipliers arranged on the left and right sides of the scintillation crystal 1340 (on the left and right sides of the scintillation crystal 1340). Fig.13A and Fig. 13B The photomultiplier 1201 may be similar to Fig. 12B 1200, each photomultiplier 1201 may include only a single photomultiplier die 1201a and a single glass component 1201b, wherein a corresponding PCB 1360 is coupled to the corresponding single photomultiplier die 1201a. In some implementations, more than one photomultiplier 1201 may be included on each of the left and right sides of the scintillation crystal 1340 in the photomultiplier and scintillation crystal assembly 1300.

[0086] Also like Fig.13A and Fig. 13B As shown, the photomultiplier and scintillation crystal assembly 1300 may include a front side (at the Fig.13AThe photomultiplier 801 of the photomultiplier and scintillation crystal assembly 1300 may be similar to Figure 8C For example, the photomultiplier 801 may include a flexible connector 860 that may connect the photomultiplier 801 to one of the PCBs 1360 and / or to an external (image processing) circuit, respectively. In this example (or in other photomultiplier and scintillation crystal assemblies), a corresponding plurality of photomultipliers 801 may be included on the bottom and back sides of the scintillation crystal 1340. Fig.13A and Fig. 13B In the views of FIG. 1 and FIG. 2 , a single photomultiplier 801 is shown on the bottom side of the scintillation crystal 1340. In these views, additional photomultipliers on the bottom side and those on the back side of the scintillation crystal 1340 are obscured.

[0087] In this example, the photomultiplier and scintillation crystal assembly 1300 also includes a water vapor intrusion resistant material 1380, which is disposed on the sidewalls of components such as the photomultiplier 1201 and the photomultiplier 801, for example, disposed on the corresponding sidewalls defined by the photomultiplier die 801a and the glass component 801b (cover), and / or on the corresponding sidewalls defined by the photomultiplier die 1201a and the glass component 1201b (cover). In some implementations, the photomultiplier and scintillation crystal assembly 1300 may include photomultipliers with different configurations, for example, photomultipliers without glass components, back-to-back photomultiplier stacks (coupled with additional scintillation crystals), etc.

[0088] In this example, the upper side (top side) of the scintillation crystal 1340 is exposed to be configured to receive gamma radiation from the patient's body during a PET scan without causing interference. For example, the upper side of the scintillation crystal 1340 may not include a photomultiplier and a water vapor intrusion resistant material. That is, in the photomultiplier and scintillation crystal assembly 1300, the photomultiplier is disposed on five of the six sides of the scintillation crystal 1340, wherein the sixth (top) side is exposed. In some implementations, a peripheral portion of the scintillation crystal 1340 may have a water vapor intrusion resistant material 1380 disposed thereon to provide protection for a corresponding interface between the scintillation crystal 1340 and the photomultiplier disposed on the scintillation crystal 1340. In some implementations, the peripheral portion may be a negligible portion of the total area of ​​the top surface of the scintillation crystal 1340. For example, in some embodiments, the scintillation crystal 1340 can be a 20 mm×20 mm×20 mm cube, and the peripheral portion of the top surface of the scintillation crystal 1340 can have a width less than 0.2 mm, so that the peripheral portion including the waterproof vapor intrusion prevention material 1380 constitutes less than three percent of the area of ​​the top surface of the scintillation crystal 1340.

[0089] Fig.14 It is shown that the FIG. 3A to FIG. 3D 1400 is a flowchart of an exemplary method of the process of Fig.14 As shown, in operation 1410, method 1400 includes coupling the photomultiplier to a corresponding carrier substrate (carrier 305), for example, in Figure 3A Arrangement shown. The carrier substrate may be a temporary carrier, such as glass, ceramic, wafer tape, etc. In this example, the photomultiplier comprises a corresponding semiconductor die (eg, silicon photomultiplier) and a corresponding glass cover (or glass component).

[0090] At operation 1420, method 1400 includes coupling a flexible connector to a photomultiplier of the structure formed at operation 1410, such as at Figure 3B Configuration of structure 300 is shown. For example, a first flexible connector can be coupled to a photomultiplier of a first structure, and a second flexible connector can be coupled to a photomultiplier of a second structure, for example to create two structures 300.

[0091] At operation 1430, method 1400 includes coupling the photomultipliers of the structure formed in operation 1420 in a back-to-back staggered configuration, such as in Figure 3C In some implementations, a single photomultiplier may be used to create the structure in operation 1420. In such an example, the photomultipliers may be coupled in a back-to-back non-staggered configuration, for example, as Fig. 9 .

[0092] In operation 1440, the carrier substrate (carrier 305) on each structure (300) may be removed to produce Figure 3D Operation 1440 may include using ultraviolet light and / or heat to release the adhesive used to couple the carrier 305 to the photomultiplier in operation 1410 .

[0093] In operation 1450, the structure produced in operation 1440 may be coupled with a scintillation crystal to produce an imaging system module, e.g. Figure 2 200 is shown. In some implementations, additional photomultipliers (eg, photomultipliers 110 and / or 120) and PCBs (eg, Figure 2 PCB 250 (shown) may be coupled with the structure produced in operation 1450 to produce an imaging system module (eg, assembly 200).

[0094] Fig.15 It is shown that the FIG. 5A to FIG. 5E1500 is a flowchart of an exemplary method of the process. As described above, FIG. 5A to FIG. 5E The process can be combined FIG. 3A to FIG. 3C 1400 (e.g., operations 1410 to 1430 of method 1400). For example, operations 1510, 1520, and 1530 may be similar or identical to operations 1410 to 1430 of method 1400. Therefore, for the sake of brevity, the description will not be repeated. Fig.15 Method 1500 discusses the details of those operations in detail.

[0095] At operation 1540, method 1500 includes removing the carrier substrate and glass component (cover) from one of the structures coupled together in operation 1530. That is, in operation 1540, along with one of the carriers 505, the glass component (cover) is removed from the structure (e.g., Figure 3B 300) is removed from the first side of the structure 300 shown in FIG. 30. In some implementations, a thermal operation can be used to release the glass components 410b and 420b from their corresponding photomultipliers. In this example, the adhesive used to couple the carrier 505 to the glass components 410b and 420b can be a high temperature adhesive having a higher release temperature than the adhesive used to couple the glass components 410b and 420b to the semiconductor die of the corresponding photomultiplier, so that the carrier 505 and the glass components 410b and 420b can be removed simultaneously.

[0096] At operation 1550, method 1500 includes transferring a carrier (a temporary carrier, such as Figure 5B The carrier 507 is shown coupled to the photomultiplier semiconductor die exposed by operation 1540. In an exemplary implementation, the carrier of operation 1540 can be coupled to the photomultiplier semiconductor die using an adhesive, which can be released using ultraviolet light and / or heat.

[0097] In operation 1560, glass components 410b and 420b are removed from the second side of the structure produced by operations 1540 and 1550, along with carrier 505, for example using ultraviolet light and / or heat. In some implementations, operation 1560 may produce Figure 5C At operation 1570, method 1500 includes coupling the photomultiplier on the second side of the structure (e.g., the structure of operation 1560) to a scintillation crystal and removing the carrier of operation 1550, e.g. Figure 5D In operation 1580, the structure of operation 1570 may be coupled with another scintillation crystal to produce a structure (eg, Figure 5E The structure shown in FIG. 4 can be used to produce an imaging system module, such as Figure 4 Module 400.

[0098] Fig.16 It is shown that the FIG. 6A to FIG. 6C 1600 is a flowchart of an exemplary method of the process. As described above, FIG. 6A to FIG. 6C The process can be combined with FIG. 5C to FIG. 5E 1500 (e.g., operations 1560 to 1580 of method 1500). For example, operations 1640 to 1670 of method 1600 may be performed similarly to FIG. 5C to FIG. 5E As shown and as directed to Fig.15 One difference with the operations discussed is that in method 1600 no temporary carrier (of operation 1650) is used.

[0099] At operation 1610, method 1600 includes coupling a flexible connector to a corresponding photomultiplier in an unseparated group of photomultipliers. Fig. 6A As shown, in some implementations, a partial sawing or laser cutting operation can be performed to form an opening 615 between photomultipliers 610 and 620 in structure 600. In some implementations, a photomultiplier group without such an opening 615 can be used, such as Figure 6B As shown. FIG. 6A to FIG. 6C In the example of , a flexible connector is not explicitly shown, but may be included as in other example implementations described herein (eg, coupled to photomultiplier 620).

[0100] At operation 1620, method 1600 includes placing the structure of operation 1610 in a back-to-back configuration (e.g., Figure 6C In operation 1630, the Figure 6C The photomultiplier of the structure is completely separated, for example, laser sawing is performed to completely separate the photomultiplier (for example, the semiconductor die and the corresponding glass component). In operation 1640, similar to Figure 5C The operation can be done from Figure 6C The carrier substrate and the glass component are removed from the first side of the structure (after separation operation 1630). In operations 1650 and 1660, similar to Figure 5D The scintillation crystal may be coupled to the photomultiplier die exposed in operation 1640 (operation 1650), and the photomultiplier die may be coupled to the scintillation crystal (operation 1650). Figure 6C The carrier substrate and glass member are removed from the second side of the structure (operation 1660). In operation 1670, the structure of operation 1660 may be coupled with another scintillator crystal to produce, for example, Figure 5E The structure shown can be used to produce imaging system modules, such as Figure 4 Module 400.

[0101] Fig.17 It is shown that the FIG. 8A to FIG. 8C process and / or for producing FIG. 8C to FIG. 8F 17 is a flow chart of an exemplary method 1700 for an exemplary structure of a semiconductor die. In operation 1710, method 1700 includes coupling a photomultiplier (semiconductor die and glass cover) to a carrier (e.g., a rigid PCB). The carrier may include electrical contact pads to which through-holes of the semiconductor die electrically coupled to the photodiode array of the photomultiplier may be bonded (e.g., using wafer-to-wafer bonding) or soldered (e.g., by solder balls). Operation 1710 may produce, for example, Fig. 8A The structure shown.

[0102] At operation 1720, method 1700 includes removing the glass cover (glass component) from the photomultiplier using, for example, UV light and / or heat, such as Figure 8B At operation 1730, method 1700 includes coupling the photomultiplier die and carrier of operation 1720 to a scintillation crystal (840), such as Figure 8C As shown. Figure 8C In an example, the area of ​​the stack including the photomultiplier die (710a) and the carrier (850) may be smaller than the area of ​​the corresponding sidewall of the scintillator crystal (840) coupled to the stack.

[0103] Then, the method 1700 includes, in operation 1740, applying a water vapor intrusion resistant material (880) to the sidewalls defined by the photomultiplier die (710a) and the sidewalls of the scintillation crystal (840) coupled to the stack produced in operation 1720. The water vapor intrusion resistant material (880) may be an epoxy, silicone, or other such material. The water vapor intrusion resistant material (880) may be disposed at least partially around the periphery of the sidewalls defined by the photomultiplier die (710a) and the carrier (850), and may prevent or reduce water vapor intrusion into the interface between the photomultiplier die (710a) and the carrier (850). Such water vapor intrusion may lead to reliability issues, such as failure of a through hole formed in the photomultiplier die 710a. Therefore, reducing or preventing such intrusion may improve reliability relative to existing implementations.

[0104] At operation 1750, the method includes coupling the flexible connector (860) to the carrier 850, also as Figure 8CAs shown. The flexible connector can be used to connect the photodiode array of the photomultiplier die (710a) to external circuits, for example, in conjunction with a through hole formed through the carrier (850), a signal trace (e.g., a signal bus) included in the carrier (850) and / or the photomultiplier die (710a), and / or a through hole formed in the photomultiplier die (710a). In operation 1760, the method 1700 includes completing an imaging system module including the structure generated by the aforementioned operations. For example, the structure generated by the method 1700 can be included in an exemplary imaging system module, such as those imaging system modules described herein (e.g., assembly 200, module 400, and modules having other configurations).

[0105] Fig.18 It is shown that the FIG. 11A to FIG. 11C 18. In operation 1810, method 1800 includes coupling photomultiplier die 1010 to a carrier, such as a rigid PCB (carrier 1050). The carrier may include electrical contact pads to which photomultiplier die 1010 is electrically coupled by wire bonding. Operation 1810 may produce, for example, Fig.11A The structure shown. In this example, the photomultiplier does not include a glass component or cover. In some implementations, operation 1810 can include removing a glass component (if present) from the photomultiplier die.

[0106] At operation 1820, method 1800 includes forming wire bonds to electrically connect the photomultiplier die to the carrier. At operation 1830, method 1800 includes coupling the photomultiplier die and carrier of operation 1820 to a scintillation crystal (1040), such as Fig. 10B As shown. Fig. 10B In an example, a stack including photomultiplier dies (1010) and a carrier (1050) may have a staggered arrangement with scintillation crystals 1040.

[0107] The method 1800 then includes, in operation 1840, applying a water vapor intrusion resistant material (1080) to the sidewalls defined by the photomultiplier die (1010) and the sidewalls of the scintillator crystal (1040) coupled to the stack created in operation 1810. In this example, the water vapor intrusion resistant material (1080) is also applied (molded, etc.) to encapsulate the wire bonds (1057). Fig. 11CAs shown, in this example, a portion of the water vapor intrusion material is disposed on the surface of the carrier coupled to the wire bond and on a portion of the sidewall of the scintillation crystal. The water vapor intrusion material may be epoxy, silicone, or other such material. The water vapor intrusion material may prevent or reduce water vapor intrusion into the interface between the photomultiplier die and the carrier, which may reduce or prevent associated reliability issues.

[0108] At operation 1850, method 1800 includes coupling the flexible connector (1060) to the carrier, also as Fig. 11C As shown. The flexible connector can be used to connect the photodiode array of the photomultiplier die to external circuits, for example, in conjunction with through holes formed through the carrier, signal traces (e.g., signal buses) included in the carrier and / or the photomultiplier die, and / or wire bonding connections. In operation 1860, method 1800 includes completing an imaging system module including the structure produced by the aforementioned operations. For example, the structure produced by method 1800 can be included in an exemplary imaging system module, such as those described herein (e.g., assembly 200, module 400, and modules having other configurations).

[0109] Fig.19 is shown for generating Fig. 12B 19. Flowchart of an exemplary method 1900 for a photomultiplier and scintillation crystal assembly of FIG. 19. In operation 1910, method 1900 includes coupling a corresponding PCB to a photomultiplier die. The PCB may be coupled to the photomultiplier die using solder (e.g., solder balls), anisotropic conductive film (ACF), or other methods. In operation 1920, method 1900 includes coupling the photomultiplier and PCB structures of operation 1910 in a back-to-back configuration, e.g., Fig. 12B At operation 1930, method 1900 includes coupling the photomultipliers to corresponding scintillation crystals. At operation 1940, a water vapor intrusion resistant material (epoxy, silicone, etc.) or the like may be applied such that the water vapor intrusion resistant material contacts (covers) sidewalls defined by the stack of back-to-back photomultipliers, contacts at least a portion of one or more sidewalls of the scintillation crystals, and partially encapsulates the PCB, wherein portions of the PCB extend beyond and are located outside of the water vapor intrusion resistant material, e.g. Fig. 12B In operation 1950, the structure generated by operations 1910 to 1940 may be used to generate an imaging system module, such as Fig.13A and Fig. 13B Imaging system module 1300.

[0110] In one general aspect, an optoelectronic device includes a first photomultiplier having a first side including a first photodiode array, and a second side opposite the first side. The optoelectronic device also includes a second photomultiplier having a first side including a second photodiode array, and a second side opposite the first side. The second side of the first photomultiplier is directly coupled to the second side of the second photomultiplier in a staggered arrangement.

[0111] Implementations may include one or more of the following features or aspects, taken alone or in combination: For example, the second side of the first photomultiplier may be welded to the second side of the second photomultiplier.

[0112] The printed circuit board may be excluded from the stack comprising the first photomultiplier and the second photomultiplier.

[0113] The first photomultiplier may include at least one cathode terminal configured to be connected to an external circuit and at least one anode terminal configured to be connected to an external circuit.

[0114] The first photomultiplier may be included in a first wafer and the second photomultiplier may be included in a second wafer.The first wafer may be wafer bonded to the second wafer.

[0115] The optoelectronic device may include a scintillation crystal coupled to a first side of the first photomultiplier. The optoelectronic device may be configured for use in a positron emission tomography (PET) scanner.

[0116] The scintillation crystal may be a first scintillation crystal.The optoelectronic device may include a second scintillation crystal coupled to the first side of the second photomultiplier.

[0117] The first photomultiplier may include: a plurality of first conductive traces disposed on a second side of the first photomultiplier; and a plurality of first through holes, the plurality of first through holes electrically coupling first portions of the plurality of first conductive traces to the first photodiode array, respectively. The second photomultiplier may include: a plurality of second conductive traces disposed on a second side of the second photomultiplier; and a plurality of second through holes, the plurality of second through holes electrically coupling first portions of the plurality of second conductive traces to the second photodiode array, respectively.

[0118] The second portions of the plurality of first conductive traces may be electrically coupled to the first portions of the plurality of second conductive traces, respectively. The second portions of the plurality of second conductive traces may be electrically coupled to the first portions of the plurality of first conductive traces, respectively.

[0119] The optoelectronic device may include a flexible connector coupled to the first photomultiplier. The flexible connector may be configured to connect the first photomultiplier to an external circuit.

[0120] The first photomultiplier may include: a first semiconductor die including a first photodiode array; and a first glass cover disposed on the first photodiode array. The second photomultiplier may include: a second semiconductor die including a second photodiode array; and a second glass cover disposed on the second photodiode array.

[0121] Each of the first photomultiplier and the second photomultiplier may not include a glass cover.

[0122] In another general aspect, an optoelectronic device includes a scintillation crystal and a semiconductor die, the semiconductor die including a first side and a second side opposite the first side. The semiconductor die includes a photomultiplier array disposed on the first side. The scintillation crystal is disposed on the first side of the semiconductor die. The optoelectronic device also includes a carrier disposed on the second side of the semiconductor die. The photomultiplier array is electrically coupled to the carrier. The optoelectronic device also includes a molding material disposed on a sidewall defined by at least one of the semiconductor die and the carrier. The molding material is configured to protect the photomultiplier array from moisture intrusion.

[0123] Implementations may include one or more of the following features or aspects, taken alone or in combination: For example, the carrier may be electrically coupled to the photomultiplier array via at least one through-hole extending through the semiconductor die from a first side of the semiconductor die to a second side of the semiconductor die.

[0124] The carrier may be electrically coupled to the photomultiplier array via at least one wire bond encapsulated in the molding material.

[0125] The optoelectronic device may include a flexible connector coupled to the carrier. The flexible connector may be configured to connect the photomultiplier array to an external circuit.

[0126] The molding material may include at least one of epoxy resin and silicone resin.

[0127] The molding material may extend over at least a portion of the second side of the semiconductor die.

[0128] The peripheral portion of the carrier may be partially etched. The molding material may extend over the partially etched peripheral portion of the carrier.

[0129] In another general aspect, an optoelectronic device includes a first semiconductor die and a second semiconductor die, the first semiconductor die including a first photomultiplier array, the second semiconductor die including a second photomultiplier array. The second semiconductor die is coupled to the first semiconductor die in a stacked manner, such that the first photomultiplier array is disposed at a proximal end of the stack, and the second photomultiplier array is disposed at a distal end of the stack. The optoelectronic device also includes a first scintillation crystal and a second scintillation crystal, the first scintillation crystal being disposed on the first semiconductor die at the proximal end of the stack, and the second scintillation crystal being disposed on the second semiconductor die at the distal end of the stack. The stack is disposed between the first scintillation crystal and the second scintillation crystal. The optoelectronic device also includes an encapsulation material disposed on a sidewall defined by the first semiconductor die and the second semiconductor die, and between the first scintillation crystal and the second scintillation crystal.

[0130] Implementations may include one or more of the following features or aspects, taken individually or in combination. For example, the optoelectronic device may include a first flexible connector coupled to a first semiconductor die. The first flexible connector may be configured to connect a first photomultiplier array to an external circuit. The optoelectronic device may include a second flexible connector coupled to a second semiconductor die. The second flexible connector may be configured to connect a second photomultiplier array to an external circuit.

[0131] The first semiconductor die may be directly coupled to the second semiconductor die.

[0132] The first scintillation crystal may be directly coupled to the first semiconductor die using an optically clear adhesive. The second scintillation crystal may be directly coupled to the second semiconductor die using an optically clear adhesive.

[0133] In another general aspect, an optoelectronic device includes a scintillation crystal, a first photomultiplier, and a second photomultiplier. The first photomultiplier is disposed on a first side wall of the scintillation crystal, and the second photomultiplier is disposed on a second side wall of the scintillation crystal. The second side wall is orthogonal to the first side wall. The optoelectronic device also includes a third photomultiplier disposed on a third side wall of the scintillation crystal, and the third side wall is parallel to the first side wall.

[0134] Implementations may include one or more of the following features or aspects, taken individually or in combination. For example, the optoelectronic device may include at least one glass component, the at least one glass component being disposed between at least one of the first photomultiplier and the first sidewall, the second photomultiplier and the second sidewall, and the third photomultiplier and the third sidewall.

[0135] The second side wall is located on a side of the scintillation crystal opposite a fourth side wall of the scintillation crystal, and the fourth side wall is configured to receive gamma radiation in a positron emission tomography scanner.

[0136] A first printed circuit board (PCB) may be electrically coupled to the first photomultiplier. A second PCB may be electrically coupled to the third photomultiplier. The third photomultiplier may be electrically coupled to the first PCB via a flexible connector.

[0137] The optoelectronic device may include a fourth photomultiplier disposed on a fourth side wall of the scintillation crystal. The fourth side wall may be orthogonal to the first side wall, the second side wall, and the third side wall. The optoelectronic device may include a fifth photomultiplier disposed on a fifth side wall of the scintillation crystal. The fifth side wall is orthogonal to the first side wall, the second side wall, and the third side wall, and is parallel to the fourth side wall.

[0138] The optoelectronic device may include a molding material encapsulating at least a portion of the scintillation crystal and contacting at least respective portions of the first, second, and third photomultipliers such that at least a fourth sidewall of the scintillation crystal is exposed through the molding material.

[0139] A number of implementations have been described, however, it will be appreciated that various modifications can be made without departing from the spirit and scope of the description.

[0140] It should also be understood that when an element is referred to as being located on another element, connected to, electrically connected to, coupled to, or electrically coupled to another element, the element may be directly located on another element, connected to, or coupled to another element, or one or more intermediate elements may be present. In contrast, when an element is referred to as being directly located on another element, directly connected to, or directly coupled to another element, there are no intermediate elements or layers. Although the terms "directly located on...", "directly connected to...", or "directly coupled to..." may not be used throughout the detailed description, an element shown as "directly located on...", "directly connected to...", or "directly coupled to..." may be referred to as such. The claims of the present application may be modified to define the illustrative relationships described in the specification or shown in the drawings.

[0141] The various devices and techniques described herein can be implemented using various semiconductor processing and / or packaging technologies. Some implementations can be implemented using various types of semiconductor processing technologies associated with semiconductor substrates, including but not limited to, for example, silicon (Si), gallium arsenide (GaAs), silicon carbide (SiC), gallium nitride (GaN), etc.

[0142] As used in this specification, the singular may include the plural unless the context clearly indicates otherwise. In addition to the directions depicted in the drawings, spatially relative terms (e.g., up, above, upper, below, below, lower, etc.) are intended to cover different directions of the device when in use or operation. In some implementations, the relative terms "above" and "below" may include vertically above and vertically below, respectively. In some implementations, the term "adjacent" may include laterally adjacent or horizontally adjacent.

[0143] Although certain features of the described implementations have been shown as described herein, many modifications, substitutions, changes, and equivalents should now be expected by those skilled in the art. Therefore, it should be understood that the appended claims are intended to cover all such modifications and changes that fall within the scope of the implementations. It should be understood that the implementations are presented only by way of example, not as a limitation, and various changes may be made in form and detail. Any part of the apparatus and / or method described herein may be combined in any combination, except mutually exclusive combinations. The implementations described herein may include various combinations and / or sub-combinations of the functions, components, and / or features of the different implementations described.

[0144] In addition, the logic and / or process flows depicted in the drawings do not require the particular order or sequence shown to achieve the desired results. In addition, other operations may be included, or operations may be eliminated from the described flows, and other components or elements may be added to or removed from the described devices, methods, and / or systems. Therefore, other implementations fall within the scope of the appended claims.

[0145] It should be understood that although the terms "first", "second", etc. can be used to describe various elements in this article, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. Without departing from the scope of the implementation of the present disclosure, the first element can be referred to as the second element, and similarly, the second element can be referred to as the first element. As used herein, the term "and / or" includes any and all combinations of one or more items in the associated listed items.

Claims

1. A photoelectric device comprising: A first photomultiplier, wherein the first photomultiplier comprises: A first side comprising a first photodiode array; and a second side opposite to the first side; as well as A second photomultiplier, wherein the second photomultiplier has: A first side including a second photodiode array; and a second side opposite to the first side, The second side of the first photomultiplier is directly coupled to the second side of the second photomultiplier in a staggered arrangement.

2. The optoelectronic device according to claim 1, wherein: The second side of the first photomultiplier is welded to the second side of the second photomultiplier.

3. The optoelectronic device according to claim 1, wherein: A printed circuit board is excluded from a stack including the first photomultiplier and the second photomultiplier.

4. The optoelectronic device according to claim 1, wherein: The first photomultiplier comprises: at least one cathode terminal configured to be connected to an external circuit; and At least one anode terminal is configured to be connected to the external circuit.

5. The optoelectronic device according to claim 1, wherein: The first photomultiplier is included in a first wafer and the second photomultiplier is included in a second wafer, the first wafer being wafer-bonded to the second wafer.

6. The optoelectronic device according to claim 1, further comprising: A scintillation crystal is coupled to a first side of the first photomultiplier, the optoelectronic device being configured for use in a positron emission tomography (PET) scanner.

7. The optoelectronic device according to claim 6, wherein: The scintillation crystal is a first scintillation crystal, and the optoelectronic device further comprises: A second scintillation crystal is coupled to the first side of the second photomultiplier.

8. The optoelectronic device according to claim 1, wherein: The first photomultiplier comprises: a plurality of first conductive traces disposed on a second side of the first photomultiplier; and a plurality of first vias electrically coupling first portions of the plurality of first conductive traces to the first photodiode array, respectively; and The second photomultiplier comprises: a plurality of second conductive traces disposed on a second side of the second photomultiplier; and A plurality of second through-holes electrically couple first portions of the plurality of second conductive traces to the second photodiode array, respectively.

9. The optoelectronic device according to claim 8, wherein: The second portions of the plurality of first conductive traces are respectively electrically coupled to the first portions of the plurality of second conductive traces; and The second portions of the second plurality of conductive traces are electrically coupled to the first portions of the first plurality of conductive traces, respectively.

10. The optoelectronic device of claim 1, further comprising a flexible connector coupled to the first photomultiplier, the flexible connector being configured to connect the first photomultiplier to an external circuit.

11. The optoelectronic device according to claim 1, wherein: The first photomultiplier comprises: a first semiconductor die comprising the first photodiode array; and a first cover glass disposed on the first photodiode array; and The second photomultiplier comprises: a second semiconductor die comprising the second photodiode array; and A second glass cover is disposed on the second photodiode array.

12. The optoelectronic device according to claim 1, wherein: Each of the first photomultiplier and the second photomultiplier does not include a glass cover.

13. A photoelectric device comprising: scintillating crystals; a semiconductor die including a first side and a second side opposite the first side, the semiconductor die including a photomultiplier array disposed on the first side, the scintillation crystal disposed on the first side of the semiconductor die; a carrier disposed on a second side of the semiconductor die, the photomultiplier array being electrically coupled to the carrier; as well as A molding material is disposed on sidewalls defined by at least one of the semiconductor die and the carrier, the molding material being configured to protect the photomultiplier array from moisture intrusion.

14. The optoelectronic device according to claim 13, wherein: The carrier is electrically coupled to the photomultiplier array by at least one through-via extending through the semiconductor die from a first side of the semiconductor die to a second side of the semiconductor die.

15. The optoelectronic device according to claim 13, wherein: The carrier is electrically coupled to the photomultiplier array via at least one wire bond encapsulated in the molding material.

16. The optoelectronic device of claim 13, further comprising a flexible connector coupled to the carrier, the flexible connector configured to connect the photomultiplier array to an external circuit.

17. The optoelectronic device according to claim 13, wherein: The molding material includes at least one of epoxy resin and silicone resin.

18. The optoelectronic device according to claim 13, wherein: The molding material extends over at least a portion of the second side of the semiconductor die.

19. The optoelectronic device according to claim 13, wherein: Partially etching the outer peripheral portion of the carrier; and The molding material extends over the partially etched peripheral portion of the carrier.

20. An optoelectronic device comprising: a first semiconductor die comprising a first photomultiplier array; a second semiconductor die, the second semiconductor die comprising a second photomultiplier array, the second semiconductor die being coupled to the first semiconductor die in a stacked manner such that the first photomultiplier array is disposed at a proximal end of the stack and the second photomultiplier array is disposed at a distal end of the stack; a first scintillation crystal disposed on the first semiconductor die at a proximal end of the stack; a second scintillation crystal disposed on the second semiconductor die at a distal end of the stack, the stack being disposed between the first scintillation crystal and the second scintillation crystal; as well as Packaging material, wherein the packaging material is configured as: on a sidewall defined by the first semiconductor die and the second semiconductor die; and The scintillation crystal is located between the first scintillation crystal and the second scintillation crystal.

21. The optoelectronic device according to claim 20, further comprising: a first flexible connector coupled to the first semiconductor die, the first flexible connector being configured to connect the first photomultiplier array to external circuitry; as well as A second flexible connector is coupled to the second semiconductor die, the second flexible connector being configured to connect the second photomultiplier array to the external circuit.

22. The optoelectronic device according to claim 20, wherein: The first semiconductor die is directly coupled to the second semiconductor die.

23. The optoelectronic device of claim 20, wherein: the first scintillator crystal is directly coupled to the first semiconductor die using an optically clear adhesive; and The second scintillator crystal is directly coupled to the second semiconductor die using an optically clear adhesive.

24. An optoelectronic device comprising: scintillating crystals; a first photomultiplier, the first photomultiplier being disposed on a first side wall of the scintillation crystal; A second photomultiplier, wherein the second photomultiplier is disposed on a second side wall of the scintillation crystal, and the second side wall is orthogonal to the first side wall; as well as A third photomultiplier is disposed on a third side wall of the scintillation crystal, and the third side wall is parallel to the first side wall.

25. The photovoltaic device according to claim 24, further comprising at least one glass component, wherein the at least one glass component is respectively disposed between at least one of the following groups: the first photomultiplier and the first sidewall; the second photomultiplier and the second sidewall; or The third photomultiplier and the third sidewall.

26. The optoelectronic device according to claim 24, wherein: The second sidewall is located on a side of the scintillation crystal opposite a fourth sidewall of the scintillation crystal, the fourth sidewall being configured to receive gamma radiation in a positron emission tomography scanner.

27. The optoelectronic device of claim 24, wherein: a first printed circuit board (PCB) electrically coupled to the first photomultiplier; A second PCB is electrically coupled to the third photomultiplier; and The third photomultiplier is electrically coupled to the first PCB through a flexible connector.

28. The optoelectronic device of claim 24, further comprising: a fourth photomultiplier, the fourth photomultiplier being disposed on a fourth side wall of the scintillation crystal, the fourth side wall being orthogonal to the first side wall, the second side wall and the third side wall; as well as A fifth photomultiplier is disposed on a fifth side wall of the scintillation crystal, wherein the fifth side wall is orthogonal to the first side wall, the second side wall and the third side wall, and is parallel to the fourth side wall.

29. The optoelectronic device of claim 24, further comprising: a molding material encapsulating at least a portion of the scintillation crystal and at least in contact with the The first photomultiplier, the second photomultiplier and the third photomultiplier are in contact with each other. At least a fourth sidewall of the scintillation crystal is left exposed through the molding material.

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