WO2022190492A1 - 光検出器 - Google Patents
光検出器 Download PDFInfo
- Publication number
- WO2022190492A1 WO2022190492A1 PCT/JP2021/045360 JP2021045360W WO2022190492A1 WO 2022190492 A1 WO2022190492 A1 WO 2022190492A1 JP 2021045360 W JP2021045360 W JP 2021045360W WO 2022190492 A1 WO2022190492 A1 WO 2022190492A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- metalens
- photodetector
- light
- light receiving
- avalanche photodiode
- Prior art date
Links
- 230000005540 biological transmission Effects 0.000 claims description 8
- 238000002955 isolation Methods 0.000 claims description 5
- 238000000926 separation method Methods 0.000 claims description 2
- 239000004065 semiconductor Substances 0.000 description 54
- 239000010410 layer Substances 0.000 description 24
- 230000005855 radiation Effects 0.000 description 20
- 238000010791 quenching Methods 0.000 description 15
- 230000000171 quenching effect Effects 0.000 description 15
- 238000001514 detection method Methods 0.000 description 14
- 238000000034 method Methods 0.000 description 14
- 230000003287 optical effect Effects 0.000 description 12
- 239000000758 substrate Substances 0.000 description 11
- 230000005684 electric field Effects 0.000 description 5
- 239000012535 impurity Substances 0.000 description 5
- 230000000052 comparative effect Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 238000009826 distribution Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 238000004544 sputter deposition Methods 0.000 description 3
- 229910004298 SiO 2 Inorganic materials 0.000 description 2
- 238000005229 chemical vapour deposition Methods 0.000 description 2
- 239000011159 matrix material Substances 0.000 description 2
- 229910052751 metal Inorganic materials 0.000 description 2
- 239000002184 metal Substances 0.000 description 2
- 230000003647 oxidation Effects 0.000 description 2
- 238000007254 oxidation reaction Methods 0.000 description 2
- 238000002161 passivation Methods 0.000 description 2
- 229910021420 polycrystalline silicon Inorganic materials 0.000 description 2
- 229920005591 polysilicon Polymers 0.000 description 2
- 229910000604 Ferrochrome Inorganic materials 0.000 description 1
- 229910005540 GaP Inorganic materials 0.000 description 1
- 229910001218 Gallium arsenide Inorganic materials 0.000 description 1
- 239000004820 Pressure-sensitive adhesive Substances 0.000 description 1
- 235000002492 Rungia klossii Nutrition 0.000 description 1
- 244000117054 Rungia klossii Species 0.000 description 1
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
- 229910004154 TaNi Inorganic materials 0.000 description 1
- 229910010413 TiO 2 Inorganic materials 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- BEZBEMZKLAZARX-UHFFFAOYSA-N alumane;gadolinium Chemical compound [AlH3].[Gd] BEZBEMZKLAZARX-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 229910021417 amorphous silicon Inorganic materials 0.000 description 1
- 238000003491 array Methods 0.000 description 1
- 229910052785 arsenic Inorganic materials 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- VNNRSPGTAMTISX-UHFFFAOYSA-N chromium nickel Chemical compound [Cr].[Ni] VNNRSPGTAMTISX-UHFFFAOYSA-N 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 229910052733 gallium Inorganic materials 0.000 description 1
- 239000002223 garnet Substances 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 229910021478 group 5 element Inorganic materials 0.000 description 1
- 230000001771 impaired effect Effects 0.000 description 1
- 239000011810 insulating material Substances 0.000 description 1
- 238000005468 ion implantation Methods 0.000 description 1
- 238000001459 lithography Methods 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 229910001120 nichrome Inorganic materials 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- LIVNPJMFVYWSIS-UHFFFAOYSA-N silicon monoxide Chemical compound [Si-]#[O+] LIVNPJMFVYWSIS-UHFFFAOYSA-N 0.000 description 1
- 229910052814 silicon oxide Inorganic materials 0.000 description 1
- 238000002834 transmittance Methods 0.000 description 1
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
- 239000010937 tungsten Substances 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
- H01L27/14—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation
- H01L27/144—Devices controlled by radiation
- H01L27/1446—Devices controlled by radiation in a repetitive configuration
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
- H01L27/14—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation
- H01L27/144—Devices controlled by radiation
- H01L27/146—Imager structures
- H01L27/14601—Structural or functional details thereof
- H01L27/14625—Optical elements or arrangements associated with the device
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J1/00—Photometry, e.g. photographic exposure meter
- G01J1/02—Details
- G01J1/04—Optical or mechanical part supplementary adjustable parts
- G01J1/0407—Optical elements not provided otherwise, e.g. manifolds, windows, holograms, gratings
- G01J1/0411—Optical elements not provided otherwise, e.g. manifolds, windows, holograms, gratings using focussing or collimating elements, i.e. lenses or mirrors; Aberration correction
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
- G01J1/00—Photometry, e.g. photographic exposure meter
- G01J1/42—Photometry, e.g. photographic exposure meter using electric radiation detectors
- G01J1/4228—Photometry, e.g. photographic exposure meter using electric radiation detectors arrangements with two or more detectors, e.g. for sensitivity compensation
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01T—MEASUREMENT OF NUCLEAR OR X-RADIATION
- G01T1/00—Measuring X-radiation, gamma radiation, corpuscular radiation, or cosmic radiation
- G01T1/16—Measuring radiation intensity
- G01T1/20—Measuring radiation intensity with scintillation detectors
- G01T1/2002—Optical details, e.g. reflecting or diffusing layers
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
- H01L27/14—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation
- H01L27/144—Devices controlled by radiation
- H01L27/146—Imager structures
- H01L27/14601—Structural or functional details thereof
- H01L27/1463—Pixel isolation structures
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/02—Details
- H01L31/0232—Optical elements or arrangements associated with the device
- H01L31/02327—Optical elements or arrangements associated with the device the optical elements being integrated or being directly associated to the device, e.g. back reflectors
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/08—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof in which radiation controls flow of current through the device, e.g. photoresistors
- H01L31/10—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof in which radiation controls flow of current through the device, e.g. photoresistors characterised by potential barriers, e.g. phototransistors
- H01L31/101—Devices sensitive to infrared, visible or ultraviolet radiation
- H01L31/102—Devices sensitive to infrared, visible or ultraviolet radiation characterised by only one potential barrier
- H01L31/107—Devices sensitive to infrared, visible or ultraviolet radiation characterised by only one potential barrier the potential barrier working in avalanche mode, e.g. avalanche photodiodes
Definitions
- the present disclosure relates to photodetectors.
- Non-Patent Document 1 describes a photodetector that includes a photodetector element including a plurality of light receiving regions and a plurality of metalens arranged on the plurality of light receiving regions.
- Non-Patent Document 1 proposes improving the light detection efficiency of the photodetector by increasing the transmittance and light collection efficiency of each metalens and increasing the depth of focus of each metalens.
- each metalens be arranged at a position close to the surface of the photodetector.
- one metalens corresponds to one light receiving area. becomes too large, the function of the metalens as a lens is impaired, and stray light increases.
- An object of the present disclosure is to provide a photodetector capable of reducing the thickness and optical loss while maintaining the function of the metalens as a lens.
- a photodetector includes a photodetector that has a surface and includes a plurality of light receiving regions arranged along the surface; and a metalens portion of the plurality of light-receiving regions and the plurality of metalens portions, in one corresponding light-receiving region and one metalens portion, one metalens portion includes a plurality of metalens arranged along the surface. include.
- a plurality of metalens correspond to one light receiving area.
- the numerical aperture of each metalens can be reasonably set by adjusting the area of each metalens according to the distance. be able to.
- the distance from each metalens portion to the surface of the photodetector can be reduced, it is possible to improve the robustness with respect to the incident angle of incident light. Therefore, according to the photodetector of one aspect of the present disclosure, it is possible to reduce the thickness and optical loss while maintaining the function of the metalens as a lens.
- the photodetector further includes a separation region that separates each of the plurality of light receiving regions, and in one corresponding light receiving region and one metalens unit, the plurality of metalens is one It may be configured to focus light into one light receiving area. According to this, it is possible to reduce the optical loss more reliably while suppressing the occurrence of crosstalk between the adjacent light receiving regions.
- the isolation regions may be trenches. According to this, it is possible to easily and reliably suppress the occurrence of crosstalk between adjacent light receiving regions.
- the photodetector according to one aspect of the present disclosure may further include a light transmission layer arranged between the surface and the plurality of metalens portions. According to this, since the distance from each metalens portion to the surface of the photodetector can be adjusted, the numerical aperture of each metalens can be set more appropriately.
- the light transmission layer may be directly formed on the surface, and the plurality of metalens portions may be directly formed on the light transmission layer. According to this, the number of interfaces existing between the metalens portion and the light-receiving region is reduced, so that optical loss due to reflection or the like at the interfaces can be reduced.
- one metalens unit in one corresponding light receiving region and one metalens unit, has a first metalens and a plurality of second metalens as a plurality of metalens, and the first The area of the metalens may be larger than the area of each of the plurality of second metalens, and the plurality of second metalens may be arranged to surround the first metalens. According to this, it is possible to reduce the number of a plurality of metalens corresponding to one light receiving area while maintaining the function of the metalens as a lens.
- the distance from one metalens portion to the surface of one light receiving region is T ( ⁇ m), and the distance of one metalens portion is When the area is S ( ⁇ m 2 ), T may be 1.0S 0.5 or less. According to this, the distance from the metalens portion to the surface of one light receiving region can be made sufficiently small with respect to the size of the metalens portion, so that it is possible to further reduce the thickness and optical loss. is possible.
- a photodetector capable of reducing the thickness and optical loss while maintaining the function of the metalens as a lens.
- FIG. 1 is a configuration diagram of a PET apparatus according to one embodiment
- FIG. 2 is a configuration diagram of the radiation detection apparatus shown in FIG. 1
- FIG. 3 is a side view of the radiation detector shown in FIG. 2
- FIG. FIG. 4 is a plan view of the photodetector shown in FIG. 3
- 4 is a circuit diagram of the photodetector shown in FIG. 3
- FIG. 5 is a plan view of a portion of the photodetector shown in FIG. 4
- FIG. 5 is a cross-sectional view of a portion of the photodetector shown in FIG. 4
- FIG. 5 is a bottom view of the photodetector shown in FIG. 4;
- FIG. 4 is a plan view of a portion of the photodetector shown in FIG. 4
- FIG. 5 is a cross-sectional view of a portion of the photodetector shown in FIG. 4
- FIG. 5 is a bottom view of the photodetector shown in FIG.
- FIG. 4 is a plan view of a portion of the photodetector shown in Figure 3;
- FIG. 10 is a cross-sectional view of a portion of the photodetector along line XX shown in FIG. 9;
- 7A and 7B are graphs showing calculation results of electric field strengths of photodetectors of Comparative Example and Example, and graphs showing intensity distributions on the surfaces of light receiving regions;
- FIG. 11 is a cross-sectional view of a portion of a photodetector of a modified example; It is a bottom view of the photodetector of a modification.
- 13 is a cross-sectional view of a portion of the photodetector along line XIII-XIII shown in FIG. 12;
- FIG. 10 is a cross-sectional view of a portion of the photodetector along line XX shown in FIG. 9;
- 7A and 7B are graphs showing calculation results of electric field strengths of photodetectors of Comparative Example and Example, and graph
- the PET apparatus 1 includes a cradle 101, a gantry 102, a control device 103, and a drive motor 104.
- Cradle 101 is arranged to pass through an opening in gantry 102 .
- a subject 105 is placed on the cradle 101 .
- the control device 103 controls the drive motor 104 according to the drive motor control signal.
- Drive motor 104 may be configured to move gantry 102 or may be configured to move cradle 101 and gantry 102 .
- the gantry 102 has multiple radiation detection devices 106 .
- a plurality of radiation detection devices 106 are arranged along the direction in which the opening of the gantry 102 penetrates.
- Each radiation detection device 106 surrounds an opening in gantry 102 .
- the control device 103 inputs a control signal for controlling each radiation detection device 106 to the gantry 102 .
- the gantry 102 outputs detection signals detected by each radiation detection device 106 to the control device 103 .
- the radiation detection device 106 includes multiple radiation detectors 2 .
- a plurality of radiation detectors 2 are arranged in an annular shape so as to surround the opening of the gantry 102 .
- the subject 105 is injected with a radioisotope (positron-emitting nuclide) that emits positrons.
- Positrons combine with negative electrons in the subject 105 to generate annihilation gamma rays.
- the annihilation gamma rays are emitted in opposite directions from the position P of the radioisotope within the subject 105 .
- the annihilation gamma rays are detected by a pair of radiation detectors 2 facing each other with the position P interposed therebetween.
- the control device 103 identifies the position P based on the time-of-flight difference of the annihilation gamma rays, and generates an image (tomographic image) regarding internal information of the subject 105 .
- the PET device 1 is a TOF-PET device.
- the radiation detector 2 includes a plurality of radiation detection units 2A.
- the plurality of radiation detection units 2A are arranged in a matrix with the X-axis direction and the Y-axis direction being the row direction and the column direction.
- Each radiation detection unit 2A includes a scintillator (light emitter) 3 and a photodetector 4 .
- the Z-axis direction is the radial direction of the ring (see FIG. 2) in which the plurality of radiation detectors 2 are arranged
- the X-axis direction is the tangential direction of the ring
- the Y-axis direction The direction is a direction perpendicular to the Z-axis direction and the X-axis direction.
- the scintillator 3 is arranged on the center side of the opening of the gantry 102 (hereinafter referred to as "light incident side") with respect to the photodetector 4 (see FIG. 2).
- the scintillator 3 emits light (fluorescence) upon incidence of annihilation gamma rays.
- the scintillator 3 is composed of Lu 2-x Y x SiO 5 :Ce (LYSO), gadolinium aluminum gallium garnet (GAGG), NaI (TI), Pr:LuAG, LaBr 2 , LaBr 3 and (Lu x Tb 1-x- y Ce y ) 3 Al 5 O 12 (i.e., LuTAG).
- LuTAG the composition ratio x is in the range of 0.5 to 1.5
- the composition ratio y is in the range of 0.01 to 0.15.
- the photodetector 4 detects the light emitted by the scintillator 3.
- the photodetector 4 has a wiring board 5 , a photodetector element 6 , a planarization film 7 , and a plurality of metalens portions 8 .
- a wiring board 5 is shared by a plurality of photodetectors 4 .
- the wiring substrate 5 , the photodetector 6 , the planarizing film 7 , and the metalens portion 8 are arranged in this order from the side opposite to the scintillator 3 . That is, the scintillator 3 is arranged on the side opposite to the photodetector 6 with respect to the metalens portion 8 .
- the scintillator 3 is bonded to the photodetector 4 with a light-transmissive adhesive.
- the photodetector 6 has a plurality of photodetectors 10 arranged two-dimensionally and a common electrode E3.
- the photodetector 6 has a rectangular shape when viewed from the Z-axis direction.
- the plurality of photodetectors 10 are arranged in a matrix with the X-axis direction and the Y-axis direction being the row direction and the column direction.
- the common electrode E3 is positioned at the center of the photodetector 6 when viewed from the Z-axis direction. Charges generated in each photodetector 10 are collected in the common electrode E3. That is, the photodetector element 6 is a SiPM having a plurality of SPADs (photodetection units 10).
- the plurality of photodetectors 10 are shown only in the regions of both ends of the photodetector 6, but the plurality of photodetectors 10 are present in the entire region of the photodetector 6 except for the common electrode E3. is formed in
- each photodetector 10 has an avalanche photodiode APD and a quenching resistor R1.
- One end of the quenching resistor R1 is electrically connected to the anode of the avalanche photodiode APD, and the other end of the quenching resistor R1 is electrically connected to the common electrode E3 via the read wiring TL of the photodetector 6. It is connected to the. That is, the plurality of photodetectors 10 are connected in parallel, and in each photodetector 10, the avalanche photodiode APD and the quenching resistor R1 are directly connected. In the photodetector 6, each avalanche photodiode APD is operated in Geiger mode.
- a reverse voltage (reverse bias voltage) higher than the breakdown voltage of the avalanche photodiode APD is applied to the avalanche photodiode APD. That is, the potential V1 is applied to the anode of the avalanche photodiode APD, and the positive potential V2 with respect to the potential V1 is applied to the cathode of the avalanche photodiode APD.
- the polarities of these potentials are relative, and for example, one of the potentials may be the ground potential.
- a signal processing unit SP is provided on the wiring board 5 .
- the signal processing unit SP processes the signal output from each photodetector element 6 with each photodetector element 6 as each channel.
- the signal processing unit SP outputs the processed signal (detection signal) to the control device 103 (see FIG. 1).
- the signal processing unit SP constitutes, for example, an ASIC (Application Specific Integrated Circuit).
- the signal processing section SP may include a CMOS circuit that converts the signal output from each photodetector element 6 into a digital pulse.
- the readout wiring TL includes a plurality of signal lines TL1 and a plurality of signal lines TL2.
- each signal line TL1 extends in the Y-axis direction between the avalanche photodiodes APD adjacent in the X-axis direction
- each signal line TL2 extends between the avalanche photodiodes APD adjacent in the Y-axis direction. It extends in the X-axis direction between them.
- the plurality of signal lines TL1 and the plurality of signal lines TL2 extend in a grid pattern so as to be connected to each other at intersections, and are electrically connected to the common electrode E3.
- each photodetector 10 one end of the quenching resistor R1 is connected to the electrode E1, and the other end of the quenching resistor R1 is connected to the signal line TL1. That is, in each photodetector 10, one end of the quenching resistor R1 is electrically connected to the anode of the avalanche photodiode APD via the electrode E1, and the other end of the quenching resistor R1 is connected to the readout line TL. It is electrically connected to the common electrode E3 via.
- the photodetector 6 has a semiconductor layer 11 .
- the semiconductor layer 11 includes an N + -type (first conductivity type) semiconductor region (first semiconductor region) 12, an N-type (first conductivity type) semiconductor region (first semiconductor region) 13, and a plurality of P-type semiconductor regions (first semiconductor regions) 13. It includes a (second conductivity type) semiconductor region (second semiconductor region) 14 and a plurality of P + -type (second conductivity type) semiconductor regions (second semiconductor regions) 15 .
- the semiconductor region 13 is formed on the surface of the semiconductor region 12 on the light incident side.
- a plurality of semiconductor regions 14 are formed within the semiconductor region 13 along the surface 6 a of the photodetector 6 .
- a plurality of semiconductor regions 15 are formed within a plurality of semiconductor regions 14 along the surface 6 a of the photodetector 6 .
- the impurity concentration of the semiconductor region 12 is higher than that of the semiconductor region 13 .
- the impurity concentration of each semiconductor region 15 is higher than that of each semiconductor region 14 .
- each avalanche photodiode APD includes an N + -type semiconductor region 12, an N-type semiconductor region 13, a P-type semiconductor region 14 forming a PN junction with the N-type semiconductor region 13, and a P + -type semiconductor region 14. and a semiconductor region 15 .
- each avalanche photodiode APD functions as a light receiving region.
- a trench 16 is formed in the surface of the semiconductor layer 11 on the light incident side so as to separate each avalanche photodiode APD. That is, the trench 16 is an isolation region that isolates each avalanche photodiode APD, which is a light receiving region.
- an insulating material such as silicon oxide, a metal material such as tungsten, and polysilicon are placed in the trench 16 .
- An insulating layer 17 is formed on the surfaces of the semiconductor regions 13, 14, and 15 on the light incident side.
- a common electrode E3 and a readout line TL are arranged on the insulating layer 17 .
- the common electrode E3 and readout line TL are covered with an insulating layer 18.
- the surface of the insulating layer 18 on the light incident side corresponds to the surface 6 a of the photodetector 6 .
- one end of the quenching resistor R1 (see FIG. 6) is electrically connected to the semiconductor regions 14 and 15 of the avalanche photodiode APD, and the other end of the quenching resistor R1 is It is electrically connected to the read wiring TL.
- a through hole TH is formed in the semiconductor layer 11 .
- An insulating layer 19 is formed on the inner surface of the through hole TH and the surface of the semiconductor region 12 opposite to the light incident side.
- a through electrode TE is arranged on the inner surface of the through hole TH with an insulating layer 19 interposed therebetween.
- the through electrode TE is connected to the common electrode E3 at the opening of the through hole TH on the light incident side.
- a bump electrode B1 is arranged on the through electrode TE via an under bump metal BM.
- the through electrodes TE and the insulating layer 19 are covered with a passivation film PF.
- An N-type semiconductor region 1PC is formed in a region surrounding the through hole TH on the surface of the semiconductor region 12 on the light incident side. The semiconductor region 1PC prevents the PN junction formed by the semiconductor region 12 and the semiconductor regions 13 and 14 from reaching the through hole TH.
- a groove is formed in the passivation film PF so as to surround the through hole TH when viewed from the Z-axis direction, and the semiconductor region 12 is exposed in the groove.
- a plurality of bump electrodes B2 are arranged on the semiconductor region 12 exposed in the groove.
- the bump electrode B ⁇ b>1 and the plurality of bump electrodes B ⁇ b>2 are electrically and physically connected to the wiring substrate 5 arranged on the side opposite to the plurality of metalens portions 8 with respect to the photodetector 6 . That is, the photodetector 6 is electrically and physically connected to the wiring board 5 .
- each avalanche photodiode APD in each photodetector 10 is operated in the Geiger mode. In this state, when light is incident on each avalanche photodiode APD from the surface 6a side, photoelectric conversion occurs in each avalanche photodiode APD, and photoelectrons (charges) are generated in each avalanche photodiode APD. When photoelectrons are generated, avalanche multiplication occurs in each avalanche photodiode APD, and amplified electron groups (charges) are collected on the common electrode E3 via each semiconductor region 15 and quenching resistor R1. The electric charge collected in the common electrode E3 from each photodetector 10 is input as a signal to the signal processor SP (see FIG. 5) of the wiring substrate 20.
- FIG. 5 The electric charge collected in the common electrode E3 from each photodetector 10 is input as a signal to the signal processor SP (see FIG. 5) of the wiring substrate 20.
- the semiconductor layer 11 is made of Si, for example.
- the P-type impurity is, for example, a Group 3 element such as B
- the N-type impurity is, for example, a Group 5 element such as N, P, As.
- Methods of adding these impurities are, for example, a diffusion method and an ion implantation method.
- Each insulating layer 17, 18, 19 is made of, for example, SiO 2 or SiN.
- a method for forming each insulating layer 17, 18, 19 is, for example, a thermal oxidation method or a sputtering method.
- the electrodes E1, E3 and the through electrodes TE are made of metal such as aluminum, for example.
- a method of forming the electrodes E1, E3 and the through electrode TE is, for example, a sputtering method.
- the resistivity of quenching resistor R1 is higher than the resistivity of electrode E1 and common electrode E3.
- the quenching resistor R1 is made of polysilicon, for example.
- a method of forming the quenching resistor R1 is, for example, a CVD (Chemical Vapor Deposition) method.
- the material of the quenching resistor R1 may be, for example, SiCr, NiCr, TaNi, FeCr, or the like.
- FIGS. 3, 9 and 10 a plurality of metalens portions 8 are provided on the planarizing film 7.
- FIG. A plurality of metalens portions 8 are arranged on the surface 6 a of the photodetector 6 with the planarizing film 7 interposed therebetween.
- Each metalens portion 8 is two-dimensionally arranged so as to overlap each avalanche photodiode APD (that is, each photodetection portion 10) when viewed from the Z-axis direction (direction intersecting the surface 6a). That is, one metalens portion 8 corresponds to one avalanche photodiode APD (opposed in the Z-axis direction).
- 9 and 10 only a portion of the photodetector 4 corresponding to one photodetection section 10 is illustrated.
- Each metalens section 8 has a plurality of metalens 9 for one avalanche photodiode APD that the photodetector section 10 has.
- Each metalens 9 is a metasurface lens formed on the surface 7 a of the planarization film 7 .
- the metalens 9 is made of a metalens material such as a-Si, HfO 2 , Nb 2 O 5 or TiO 2 .
- a method of forming the metalens 9 is, for example, a method of etching the planarizing film 7 to form a plurality of grooves in the planarizing film 7 .
- a plurality of metalens 9 are configured to converge light within the avalanche photodiode APD of one corresponding photodetector 10 .
- the metalens 9 is configured, for example, based on the phase design of a Fresnel lens.
- the outer diameter of the metalens 9 is, for example, several micrometers to several tens of micrometers.
- the outer diameter of the metalens 9 is designed according to the size of the photodetector 10 corresponding to the metalens 8 having the metalens 9 .
- the thickness of the metalens portion 8 in the Z-axis direction is, for example, about 500 nm.
- a single period of the metalens portion 8 is equal to or less than the wavelength of the light L, and is, for example, about 250 nm.
- the planarizing film 7 is arranged between the surface 6 a of the photodetector 6 and the plurality of metalens portions 8 .
- the planarization film 7 is a light transmission layer directly formed on the surface 6a.
- the planarizing film 7 is made of, for example, SiO 2 , GaAs, GaP, Si, SiC, or the like.
- a method for forming the planarizing film 7 is, for example, a thermal oxidation method or a sputtering method.
- the thickness of the planarizing film 7 is, for example, several ⁇ m.
- each metalens 9 is the light-incident surface of the corresponding avalanche photodiode APD (that is, the corresponding Light L is focused on the surface 15 a ) of one semiconductor region 15 .
- T ( ⁇ m) is the distance between the light incident side surface of one avalanche photodiode APD (that is, the surface 15a of the semiconductor region 15) and the metalens portion 8 in the Z-axis direction.
- S ( ⁇ m 2 ) the area of the portion 8 is S ( ⁇ m 2 )
- the area of the metalens portion 8 is, for example, several hundred ⁇ m 2 to several thousand ⁇ m 2 . Therefore, the distance in the Z-axis direction between the surface on the light incident side of one avalanche photodiode APD and the metalens portion 8 can be set to several tens of ⁇ m or less.
- a plurality of metalens 9 correspond to one avalanche photodiode APD.
- the numerical aperture of each metalens 9 can be adjusted by adjusting the area of each metalens 9 according to the distance. can be set easily.
- the robustness against the incident angle of the light L can be improved. Therefore, according to the photodetector 4, it is possible to reduce the thickness and optical loss while maintaining the function of the metalens 9 as a lens.
- the photodetector element 6 includes a trench 16 separating each avalanche photodiode APD, and in one avalanche photodiode APD and one metalens portion 8, a plurality of metalens 9 are arranged in one. It is configured to focus light into one avalanche photodiode APD. As a result, it is possible to more reliably reduce optical loss while suppressing the occurrence of crosstalk between adjacent avalanche photodiodes APD.
- a plurality of metalens 9 are configured to avoid the trenches 16 and collect light.
- the metalens portion 8 since the metalens portion 8 includes a plurality of metalens 9, it is possible to improve the degree of freedom in phase design. Become.
- the metalens portion 8 since the metalens portion 8 includes a plurality of metalens 9, the degree of freedom in phase design can be improved. It can also be designed to focus the light towards the area of sensitivity).
- the metalens 9 can be designed, for example, to focus light toward the central region of the avalanche photodiode APD when the avalanche photodiode APD is viewed from the light incident side.
- the central region of the avalanche photodiode APD means a region that exists within the avalanche photodiode APD and has the same center of gravity as the avalanche photodiode APD when the avalanche photodiode APD is viewed from the light incident side.
- the central region of the avalanche photodiode APD has, for example, a shape substantially similar to that of the avalanche photodiode APD.
- the central region of the avalanche photodiode APD may be a particularly sensitive region of the light receiving region. As a result, it is possible to more reliably reduce optical loss while suppressing the occurrence of crosstalk between adjacent avalanche photodiodes APD.
- a planarizing film 7 is arranged between the surface 6 a of the photodetector 6 and the plurality of metalens portions 8 .
- the distance from each metalens portion 8 to the surface 6a of the photodetector 6 can be adjusted, so that the numerical aperture of each metalens 9 can be set more appropriately.
- the planarizing film 7 is directly formed on the surface 6 a of the photodetector 6 , and the plurality of metalens portions 8 are directly formed on the planarizing film 7 . This reduces the number of interfaces existing between the metalens portion 8 and the avalanche photodiode APD, thereby reducing optical loss due to reflection at the interfaces.
- the distance from one metalens portion 8 to the surface of the avalanche photodiode APD on the light incident side is defined as T ( ⁇ m).
- T is 1.0S0.5 or less. According to this, the distance from the metalens portion 8 to the surface of the avalanche photodiode APD on the light incident side can be made sufficiently small relative to the size of the metalens portion 8, so that the thickness of the photodetector 4 can be reduced. And it is possible to further reduce the optical loss.
- the distance from one metalens portion 8 to the surface of the avalanche photodiode APD on the light incident side is defined as T ( ⁇ m), and the metalens portion
- the metalens portion When the outer diameter of one metalens 9 in 8 is D ( ⁇ m), the condensing angle ⁇ of one metalens 9 is tan ⁇ 1 (D/2T).
- Each of the plurality of metalens 9 in the metalens portion 8 can adjust the outer diameter of each metalens 9 according to the distance from the metalens portion 8 to the surface of the avalanche photodiode APD on the light incident side.
- FIG. 11A is a graph showing the calculation results of the electric field intensity of a photodetector of a comparative example in which the metalens portion includes one metalens (outer diameter of 50 ⁇ m) in one corresponding light receiving region and one metalens portion;
- FIG. 11(b) shows the electric field strength of an example in which the metalens portion includes a plurality of metalens (25 pieces for one light receiving region) (outer diameter: 10 ⁇ m) in one corresponding light receiving region and one metalens portion.
- the planarizing film 7 may be an insulating layer covering the readout line TL, and the surface of the insulating layer 17 on the light incident side may be the surface 6 a of the photodetector 6 . 12, the plurality of metalens portions 8 are arranged on the surface 21a of the light transmitting substrate 21, and the light transmitting substrate 21 is formed on the surface 6a of the photodetecting element 6. As shown in FIG. may be bonded to the surface 6a via the pressure-sensitive adhesive layer 22.
- a method of forming the metalens portion 8 on the light-transmitting substrate 21 is, for example, to form a film made of a metalens material on the surface 21a of the light-transmitting substrate 21, and then form an EB mask layer on the film by EB lithography. Then, the film and the layer are etched to form a plurality of metalens portions 8 on the surface 21a of the light-transmitting substrate 21. As shown in FIG.
- the thickness of the light-transmitting substrate 21 is, for example, several tens of ⁇ m to several hundred ⁇ m.
- the size of the metalens 9 arranged on the surface 21a of the light transmitting substrate 21 is the size from the metalens portion 8 to the light incident surface of the avalanche photodiode APD. It can be adjusted according to the distance.
- the metalens section 8 may have a first metalens 91 and a plurality of second metalens 92 as the plurality of metalens 9 .
- the area of the first metalens 91 is larger than the area of each of the second metalens 92 .
- the plurality of second metalens 92 are arranged so as to surround the first metalens 91 when viewed from the Z-axis direction.
- each of the plurality of metalens 9 in the metalens portion 8 may not have regularity and/or uniformity, and these may be designed according to the shape of the light receiving area. can be done. 13 and 14, only a portion of the photodetector 4 corresponding to one photodetection section 10 is shown.
- the photodetector element 6 as a SiPM having a plurality of SPADs has other configurations such as a configuration in which the arrangement of the N-type semiconductor region and the P-type semiconductor region is reversed. good too.
- the photodetector 6 may have a configuration other than the avalanche photodiode APD as the plurality of light receiving regions.
- each metalens 9 may condense the light L at a position other than the surface of the corresponding avalanche photodiode APD on the light incident side.
- the light L may be condensed in the direction opposite to the light incident side with respect to the surface of .
- Each metalens 9 may, for example, focus the light L inside the light-receiving region (for example, within the region of the semiconductor region 15).
- the focal length of each metalens 9 can be made equal to or greater than the distance T ( ⁇ m) from the metalens portion 8 to the surface of the avalanche photodiode APD on the light incident side by concentrating the light inside the light receiving region by each metalens 9. can. Therefore, when the outer diameter of each metalens 9 is D ( ⁇ m), the light collection angle ⁇ is tan ⁇ 1 (D/2T). Light angles can be made smaller. Thereby, generation of stray light can be further suppressed.
- the photodetector 6 is not limited to a front-illuminated type, and may be a back-illuminated type. Also, the photodetector 6 may have an isolation region constituted by a semiconductor region of the first conductivity type, a semiconductor region of the second conductivity type, a light shielding film, etc., instead of the trench 16 . The photodetector element 6 may not have an isolation region separating each avalanche photodiode APD.
- the detection target of the radiation detector 2 is not limited to annihilation ⁇ -rays, and may be other radiation such as X-rays.
- the light-emitting body that emits light upon incidence of radiation is not limited to the scintillator 3, and may be another light-emitting body such as a Cherenkov radiator.
- Photodetector 6 Photodetector 6a Surface 7 Flattening film 8 Metalens part 9 Metalens 16 Trench 21 Light transmission substrate 91 First metalens 92 Second 2 metalens, APD: avalanche photodiode (light receiving region) L: light.
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- General Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Life Sciences & Earth Sciences (AREA)
- High Energy & Nuclear Physics (AREA)
- Molecular Biology (AREA)
- Health & Medical Sciences (AREA)
- Light Receiving Elements (AREA)
- Photometry And Measurement Of Optical Pulse Characteristics (AREA)
- Measurement Of Radiation (AREA)
- Solid State Image Pick-Up Elements (AREA)
Abstract
Description
T≦1.0S0.5…(1)
Claims (7)
- 表面を有し、前記表面に沿って配置された複数の受光領域を含む光検出素子と、
前記複数の受光領域に対応するように前記表面上に配置された複数のメタレンズ部と、を備え、
前記複数の受光領域及び前記複数のメタレンズ部のうち、対応する一つの受光領域及び一つのメタレンズ部において、前記一つのメタレンズ部は、前記表面に沿って配置された複数のメタレンズを含む、光検出器。 - 前記光検出素子は、前記複数の受光領域のそれぞれを分離する分離領域を更に含み、
対応する前記一つの受光領域及び前記一つのメタレンズ部において、前記複数のメタレンズは、前記一つの受光領域内に光を集光するように構成されている、請求項1に記載の光検出器。 - 前記分離領域は、トレンチである、請求項2に記載の光検出器。
- 前記表面と前記複数のメタレンズ部との間に配置された光透過層を更に備える、請求項1~3のいずれか一項に記載の光検出器。
- 前記光透過層は、前記表面に直接形成されており、
前記複数のメタレンズ部は、前記光透過層に直接形成されている、請求項4に記載の光検出器。 - 対応する前記一つの受光領域及び前記一つのメタレンズ部において、前記一つのメタレンズ部は、前記複数のメタレンズとして、第1メタレンズ及び複数の第2メタレンズを有し、
前記第1メタレンズの面積は、前記複数の第2メタレンズのそれぞれの面積よりも大きく、
前記複数の第2メタレンズは、前記第1メタレンズを包囲するように配置されている、請求項1~5のいずれか一項に記載の光検出器。 - 対応する前記一つの受光領域及び前記一つのメタレンズ部において、前記一つのメタレンズ部から前記一つの受光領域の表面までの距離をT(μm)とし、前記一つのメタレンズ部の面積をS(μm2)とするとき、
Tは、1.0S0.5以下である、請求項1~6のいずれか一項に記載の光検出器。
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202180095497.8A CN116964748A (zh) | 2021-03-11 | 2021-12-09 | 光检测器 |
DE112021007258.7T DE112021007258T5 (de) | 2021-03-11 | 2021-12-09 | Fotodetektor |
US18/279,263 US20240145493A1 (en) | 2021-03-11 | 2021-12-09 | Photodetector |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2021039297A JP2022139071A (ja) | 2021-03-11 | 2021-03-11 | 光検出器 |
JP2021-039297 | 2021-03-11 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2022190492A1 true WO2022190492A1 (ja) | 2022-09-15 |
Family
ID=83227859
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2021/045360 WO2022190492A1 (ja) | 2021-03-11 | 2021-12-09 | 光検出器 |
Country Status (5)
Country | Link |
---|---|
US (1) | US20240145493A1 (ja) |
JP (1) | JP2022139071A (ja) |
CN (1) | CN116964748A (ja) |
DE (1) | DE112021007258T5 (ja) |
WO (1) | WO2022190492A1 (ja) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2024081647A1 (en) * | 2022-10-14 | 2024-04-18 | Qualcomm Incorporated | Systems and techniques for forming meta-lenses |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20190019828A1 (en) * | 2017-07-12 | 2019-01-17 | Applied Materials, Inc. | Shaped color filter |
US20200264043A1 (en) * | 2019-02-19 | 2020-08-20 | Renesas Electronics America Inc. | Spectrometer on a chip |
JP2021002542A (ja) * | 2019-06-19 | 2021-01-07 | ソニーセミコンダクタソリューションズ株式会社 | アバランシェフォトダイオードセンサ及び測距装置 |
-
2021
- 2021-03-11 JP JP2021039297A patent/JP2022139071A/ja active Pending
- 2021-12-09 WO PCT/JP2021/045360 patent/WO2022190492A1/ja active Application Filing
- 2021-12-09 US US18/279,263 patent/US20240145493A1/en active Pending
- 2021-12-09 CN CN202180095497.8A patent/CN116964748A/zh active Pending
- 2021-12-09 DE DE112021007258.7T patent/DE112021007258T5/de active Pending
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20190019828A1 (en) * | 2017-07-12 | 2019-01-17 | Applied Materials, Inc. | Shaped color filter |
US20200264043A1 (en) * | 2019-02-19 | 2020-08-20 | Renesas Electronics America Inc. | Spectrometer on a chip |
JP2021002542A (ja) * | 2019-06-19 | 2021-01-07 | ソニーセミコンダクタソリューションズ株式会社 | アバランシェフォトダイオードセンサ及び測距装置 |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2024081647A1 (en) * | 2022-10-14 | 2024-04-18 | Qualcomm Incorporated | Systems and techniques for forming meta-lenses |
Also Published As
Publication number | Publication date |
---|---|
DE112021007258T5 (de) | 2023-12-21 |
US20240145493A1 (en) | 2024-05-02 |
JP2022139071A (ja) | 2022-09-26 |
CN116964748A (zh) | 2023-10-27 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US9748428B2 (en) | Light detection device including a semiconductor light detection element with a through-hole electrode connection, a mounting substrate and a light-transmissive substrate | |
US20180331134A1 (en) | Photodiode array | |
EP2960939B1 (en) | Detector, pet system and x-ray ct system | |
JP5437791B2 (ja) | (Bi)CMOSプロセスによるアバランシェフォトダイオードの製造方法 | |
WO2013058001A1 (ja) | 光検出装置 | |
US20020148967A1 (en) | Junction-side illuminated silicon detector arrays | |
JP6663167B2 (ja) | 光検出装置 | |
WO2010031011A2 (en) | Thin active layer fishbone photodiode with a shallow n+ layer and method of manufacturing the same | |
JP2017219443A (ja) | 光検出ユニット、光検出装置、及び、光検出ユニットの製造方法 | |
WO2022190492A1 (ja) | 光検出器 | |
CN109342465B (zh) | 具有光电二极管的集成闪烁体网格 | |
CN114586160A (zh) | 光接收元件和距离测量装置 | |
WO2022097358A1 (ja) | 光検出器、放射線検出器及びpet装置 | |
US7825384B1 (en) | Quantum detector array | |
US20230132945A1 (en) | Photodetector and electronic apparatus | |
JP2016174048A (ja) | 光検出装置 | |
US20220260736A1 (en) | Silicon photomultipliers for positron emission tomography imaging systems | |
KR100882537B1 (ko) | 일체화된 픽셀형 섬광체를 갖는 방사선 영상 검출기 모듈및 그 제작방법 | |
WO2022077456A1 (zh) | 单光子雪崩二极管、图像传感器及电子设备 | |
WO2023233768A1 (ja) | 放射線検出器及び放射線検出装置 | |
US20160181307A1 (en) | Integrated scintillator grid with photodiodes | |
US9754992B2 (en) | Integrated scintillator grid with photodiodes | |
US9419046B2 (en) | Integrated scintillator grid with photodiodes |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 21930337 Country of ref document: EP Kind code of ref document: A1 |
|
WWE | Wipo information: entry into national phase |
Ref document number: 18279263 Country of ref document: US |
|
WWE | Wipo information: entry into national phase |
Ref document number: 202180095497.8 Country of ref document: CN |
|
WWE | Wipo information: entry into national phase |
Ref document number: 112021007258 Country of ref document: DE |
|
122 | Ep: pct application non-entry in european phase |
Ref document number: 21930337 Country of ref document: EP Kind code of ref document: A1 |