WO2022011701A1 - Diode à avalanche à photon unique et son procédé de fabrication, dispositif de détection de photons et système - Google Patents

Diode à avalanche à photon unique et son procédé de fabrication, dispositif de détection de photons et système Download PDF

Info

Publication number
WO2022011701A1
WO2022011701A1 PCT/CN2020/102783 CN2020102783W WO2022011701A1 WO 2022011701 A1 WO2022011701 A1 WO 2022011701A1 CN 2020102783 W CN2020102783 W CN 2020102783W WO 2022011701 A1 WO2022011701 A1 WO 2022011701A1
Authority
WO
WIPO (PCT)
Prior art keywords
doping
material layer
doping structure
layer
photon avalanche
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/CN2020/102783
Other languages
English (en)
Chinese (zh)
Inventor
杨玉怀
高桥秀和
何志宏
谢承志
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Huawei Technologies Co Ltd
Original Assignee
Huawei Technologies Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Huawei Technologies Co Ltd filed Critical Huawei Technologies Co Ltd
Priority to PCT/CN2020/102783 priority Critical patent/WO2022011701A1/fr
Priority to CN202080099985.1A priority patent/CN115428152B/zh
Priority to CN202512049619.2A priority patent/CN122028525A/zh
Publication of WO2022011701A1 publication Critical patent/WO2022011701A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10F—INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION
    • H10F30/00—Individual radiation-sensitive semiconductor devices in which radiation controls the flow of current through the devices, e.g. photodetectors
    • H10F30/20—Individual radiation-sensitive semiconductor devices in which radiation controls the flow of current through the devices, e.g. photodetectors the devices having potential barriers, e.g. phototransistors
    • H10F30/21—Individual radiation-sensitive semiconductor devices in which radiation controls the flow of current through the devices, e.g. photodetectors the devices having potential barriers, e.g. phototransistors the devices being sensitive to infrared, visible or ultraviolet radiation
    • H10F30/22—Individual radiation-sensitive semiconductor devices in which radiation controls the flow of current through the devices, e.g. photodetectors the devices having potential barriers, e.g. phototransistors the devices being sensitive to infrared, visible or ultraviolet radiation the devices having only one potential barrier, e.g. photodiodes
    • H10F30/225—Individual radiation-sensitive semiconductor devices in which radiation controls the flow of current through the devices, e.g. photodetectors the devices having potential barriers, e.g. phototransistors the devices being sensitive to infrared, visible or ultraviolet radiation the devices having only one potential barrier, e.g. photodiodes the potential barrier working in avalanche mode, e.g. avalanche photodiodes
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10F—INORGANIC SEMICONDUCTOR DEVICES SENSITIVE TO INFRARED RADIATION, LIGHT, ELECTROMAGNETIC RADIATION OF SHORTER WAVELENGTH OR CORPUSCULAR RADIATION
    • H10F39/00—Integrated devices, or assemblies of multiple devices, comprising at least one element covered by group H10F30/00, e.g. radiation detectors comprising photodiode arrays
    • H10F39/10—Integrated devices

Definitions

  • the present application relates to the technical field of semiconductor manufacturing, and in particular, to a single-photon avalanche diode and a manufacturing method thereof, a light detection device and a system.
  • photodetectors are used in many scenarios.
  • the photodetector can receive optical signals, and the optical signals excite photoelectrons inside the photodetector and are collected, that is, the photodetector can generate corresponding electrical signals based on the optical signals. Realize the conversion from optical signal to electrical signal.
  • the object to be measured can be detected by means of time of flight (ToF), specifically, a laser signal is emitted by the radar transmitting system, and the laser signal is transmitted through the After the object to be measured is reflected, it is received by the photodetector, and the flight (round-trip) time of the laser signal is obtained by using the emission time and reception time of the laser signal, so that the distance between the lidar system and the object to be measured (that is, the distance of the object to be measured) can be determined. depth information), and then obtain the position information of the object to be measured.
  • Lidar systems can be used in vehicles.
  • photodetectors can also be installed in other terminals and wearable devices with photoelectric conversion functions.
  • the single photon avalanche diode is a component of a photodetector, and its working principle is that the photogenerated carriers (electron-hole pairs) generated by the photoelectric effect under the action of the optical signal, at high
  • the electric field region (the reverse voltage of the PN junction) is rapidly accelerated when moving, and one or more collisions may occur during the movement.
  • the collision ionization effect secondary and tertiary new electron-hole pairs are generated, resulting in an avalanche multiplication effect, which makes the load
  • the number of carriers increases rapidly, resulting in a relatively large photogenerated current. Therefore, single-photon avalanche diodes can detect very weak photons (on the order of single photons), sample and calculate the light field of the imaging target in time and space.
  • Single-photon avalanche diode is the basic device of many optoelectronic devices, and its performance affects the performance of optoelectronic devices.
  • DToF direct time of flight
  • PDE photon detection efficiency
  • the light detection efficiency of single-photon avalanche diodes is low. tend to be lower. Therefore, in order to achieve better performance of optoelectronic devices, it is urgent to improve the performance of single-photon avalanche diodes.
  • a first aspect of the present application provides a single-photon avalanche diode and a method for manufacturing the same, a light detection device and a system, which can improve light detection efficiency.
  • a single-photon avalanche diode including a first doping material layer, a second doping structure, a first doping structure and a cover material; wherein the first doping material layer and The second doping structure is stacked in the longitudinal direction, the cross section of the second doping structure is smaller than that of the first doping material layer, the doping types of the first doping material layer and the second doping structure are the same, and the second doping structure is the same.
  • the doping concentration of the structure is higher than that of the first doping material layer, the first doping structure covers the surface of the second doping structure facing the first doping material layer and covers the sidewall of the second doping structure, the first doping structure
  • the doping type is opposite to that of the second doping structure.
  • the region adjacent to the first doping structure and the second doping structure is used to form an avalanche region, and a covering material covers the surface of the first doping material layer. for providing an electric field for moving the multiples in the first doped material layer from the edge to the center.
  • the first doping structure is formed on one side of the horizontal surface and the sidewall of the second doping structure, and the region adjacent to the first doping structure and the second doping structure is used for forming Avalanche region, and the high field region of the corner region adjacent to the second doping structure and the first doping structure is more likely to form an avalanche region, that is, the avalanche effect occurs in the edge region of the second doping structure and the first doping structure.
  • the cover material can provide an electric field that makes the multiple carriers in the first doped material layer move from the edge to the center, which is beneficial to the photogenerated carriers in the first doped material layer to the avalanche region. Therefore, the charge collection efficiency is improved to a certain extent, so the device has a high quantum efficiency, which can have a high photodetection efficiency.
  • the single-photon avalanche diode further includes a third doping structure
  • the third doping structure is located on an unoccupied portion of the second doping structure.
  • Part of the sidewall covered by the first doping structure, or the third doping structure is located between the second doping material layer and the third doping material layer, and the second doping structure the part of the sidewall not covered by the first doping structure;
  • the doping type of the third doping structure is the same as that of the second doping structure, and the doping concentration is lower than that of the second doping structure.
  • a third doping structure may be formed to cover a part of the sidewall of the second doping structure away from the first doping material layer, and the doping type of the third doping structure is consistent with the second doping structure , and the doping concentration is lower than that of the second doping structure, so that when a covering material is formed on the surface of the first doping material layer where the second doping structure is formed, the third doping structure can be formed with the second doping structure
  • the sidewalls of the second doping structure can be used as a buffer layer between the second doping structure and the cover material, thereby reducing the surface potential of the device plane formed by the second doping structure and the cover material, and reducing the dark current at the device plane.
  • the first doping structure extends longitudinally through the first doping material layer.
  • the first doping structure may vertically penetrate the first doping material layer, so that the electric field generated by the first doping structure can keep the photo-generated carriers in the first doping material layer away from the first doping structure , so that the photogenerated carriers are concentrated to the central position between the first doping structure and the filling material, thereby improving the quantum efficiency.
  • the covering material is a fourth doping structure and/or a dielectric layer, and the dielectric layer is charged; the doping type of the fourth doping structure is the same as that of the first doping In contrast to the material layer, the charge type of the dielectric layer is the same as the charge type of the polytrons in the first doped material layer.
  • the cover material may be a third doping structure and/or a dielectric layer, and the dielectric layer may be charged, so that the electric field generated by the third doping material structure and/or the dielectric layer can be used to promote the charge carriers to The center movement of the first doped material layer improves the charge collection efficiency.
  • the covering material is connected to the first lead end, and the first lead end and the second doping structure are used to connect different bias voltages respectively.
  • the cover material can be connected to the first lead-out terminal, and the first lead-out terminal can be connected to the second doping structure with different bias voltages respectively, so as to provide a control voltage for the single-photon avalanche diode while promoting charge collection .
  • the second doping structure is located in the middle of the first doping material layer, or the second doping structure is disposed along the edge of the first doping material layer, or The second doping structure is located at the top corner of the first doping material layer.
  • the second doping structure may be located at different positions of the first doping material layer, so that the structure of the single-photon avalanche diode is different, and is more adaptable to different scenarios.
  • the single-photon avalanche diode further includes a substrate
  • a first doping material layer and a second doping structure are sequentially arranged on the substrate from bottom to top.
  • the single-photon avalanche diode can be formed in a front-illuminated light detection device, and the substrate can be sequentially provided with a first doping material layer and a second doping structure from bottom to top, which is beneficial to the second doping connection of heterostructures.
  • the single-photon avalanche diode further includes a substrate
  • a second doping structure and a first doping material layer are sequentially arranged on the substrate from bottom to top.
  • the single-photon avalanche diode may be formed in a back-illuminated light detection device, and the substrate may be provided with a second doping structure and a first doping material layer in sequence from bottom to top, so that light can be The first doping material layer is directly irradiated from top to bottom without being blocked, which is beneficial to improve the light absorption efficiency.
  • the single-photon avalanche diode further includes a microlens layer
  • the microlens layer is located on a surface away from the substrate; the focus of the microlens layer is between the edge of the first doping material layer and the second doping structure.
  • the single-photon avalanche diode may further include a microlens layer, the microlens layer may be located on a surface away from the substrate, and the microlens layer may be focused on the edge of the first doping material layer and the second doping structure In between, the light can pass through the microlens layer to reach the first doping material layer and be focused, thereby improving the light conversion efficiency.
  • the microlens layer is a microlens arranged in an array, and the microlens includes a convex lens and/or a Fresnel lens.
  • the microlens layer may be microlenses arranged in an array, and the microlenses may be convex lenses and/or Fresnel lenses, so as to realize the focusing of the light beam, wherein the Fresnel lens and the convex lens can achieve the same focusing effect At the same time, it can have a smaller vertical size, which is beneficial to reduce the size of the device.
  • the single-photon avalanche diode further includes an inverted pyramid structure; the inverted pyramid structure is located on a side away from the substrate.
  • the single-photon avalanche diode may further include an inverted pyramid structure, the inverted pyramid structure may be located on a side away from the substrate, and the inverted pyramid structure has a surface that is not parallel to the surface of the substrate.
  • a method for manufacturing a single-photon avalanche diode including:
  • the second doping structure, the first doping structure and the first doping material layer are sequentially formed on the substrate from bottom to top; or, the first doping material layer, a first doping structure and a second doping structure;
  • the cross section of the second doping structure is smaller than that of the first doping material layer; the doping types of the first doping material layer and the second doping structure are the same, and the second doping structure is of the same doping type.
  • the doping concentration of the doping structure is higher than that of the first doping material layer; the first doping structure covers the surface of the second doping structure facing the first doping material layer, and covers the second doping material layer sidewalls of the doping structure; the doping type of the first doping structure is opposite to that of the second doping structure, and the region adjacent to the first doping structure and the second doping structure is used for an avalanche region is formed; a covering material is formed on the surface of the first doping material layer, which is used for providing an electric field for moving the multi-subs in the first doping material layer from the edge to the center.
  • the method further includes:
  • the third doping structure is located on an unoccupied portion of the second doping structure.
  • Part of the sidewall covered by the first doping structure, or the third doping structure is located between the second doping material layer and the third doping material layer, and the second doping structure the part of the sidewall not covered by the first doping structure;
  • the doping type of the third doping structure is the same as that of the second doping structure, and the doping concentration is lower than that of the second doping structure.
  • the first doping structure extends longitudinally through the first doping material layer.
  • the covering material is a fourth doping structure and/or a dielectric layer, and the dielectric layer is charged; the doping type of the fourth doping structure is the same as that of the first doping In contrast to the material layer, the charge type of the dielectric layer is the same as the charge type of the polytrons in the first doped material layer.
  • the covering material is connected to the first lead end, and the first lead end and the second doping structure are used to connect different bias voltages respectively.
  • the second doping structure is located in the middle of the first doping material layer, or the second doping structure is disposed along the edge of the first doping material layer, or The second doping structure is located at the top corner of the first doping material layer.
  • the method further includes a microlens layer
  • the microlens layer is located on a surface away from the substrate; the focus of the microlens layer is between the edge of the first doping material layer and the second doping structure.
  • the microlens layer is a microlens arranged in an array, and the microlens includes a convex lens and/or a Fresnel lens.
  • the method further includes an inverted pyramid structure; the inverted pyramid structure is located on a side away from the substrate.
  • a photodetector device including a plurality of photodetection units; the photodetection units include a logic circuit layer and the single-photon avalanche provided in the first aspect of the embodiments of the present application a diode; the logic circuit layer is electrically connected to the single-photon avalanche diode.
  • isolation trenches are used to isolate the single-photon avalanche diodes in different detection units.
  • the isolation trench is filled with insulating material; or the sidewall of the isolation trench is formed with a dielectric layer, and the isolation trench is further filled with a metal filling layer.
  • a light detection system including a light emitting device and the light detection device provided in the third aspect of the embodiments of the present application;
  • the light emitting device is used for emitting light signals to the object to be measured
  • the light detection device is used for generating an avalanche current based on the light signal reflected by the object to be tested.
  • the embodiments of the present application have the following advantages:
  • Embodiments of the present application provide a single-photon avalanche diode, a manufacturing method thereof, a light detection device, and a system, wherein the single-photon avalanche diode includes a first doping material layer, a second doping structure, a first doping structure, and a covering material , wherein the first doping material layer and the second doping structure are stacked in the longitudinal direction, and the cross section of the second doping structure is smaller than the first doping material layer, the first doping material layer and the second doping structure doping
  • the impurity types are consistent, the doping concentration of the second doping structure is higher than that of the first doping material layer, the first doping structure is located between the second doping structure and the first doping material layer, and covers the second doping structure
  • the sidewall of the doping structure, the doping type of the first doping structure is opposite to that of the second doping structure, and the adjacent regions of the first doping structure and the second doping structure are used to form an
  • the first doping structure is formed on one side of the horizontal surface and the sidewall of the second doping structure, and the region adjacent to the first doping structure and the second doping structure is used for forming Avalanche region, and the high field region of the corner region adjacent to the second doping structure and the first doping structure is more likely to form an avalanche region, that is, the avalanche effect occurs in the edge region of the second doping structure and the first doping structure.
  • the cover material can provide an electric field that makes the multiple carriers in the first doped material layer move from the edge to the center, which is beneficial to the photogenerated carriers in the first doped material layer to the avalanche region. Therefore, the charge collection efficiency is improved to a certain extent, so the device has a high quantum efficiency, which can have a high photodetection efficiency.
  • FIG. 1 is a schematic structural diagram of a current single-photon avalanche diode
  • FIG. 2 is a schematic structural diagram of a light detection system provided by an embodiment of the present application.
  • FIG. 3 is a schematic structural diagram of a light detection unit according to an embodiment of the present application.
  • FIG. 4 is a schematic structural diagram of a single-photon avalanche diode according to an embodiment of the present application.
  • FIG. 5 is a schematic diagram of another single-photon avalanche diode provided by an embodiment of the present application.
  • FIG. 6 is a schematic projection diagram of the second doping structure and the first doping structure in a horizontal plane according to an embodiment of the present application
  • FIG. 7 is a schematic diagram of an equipotential line provided by an embodiment of the present application.
  • FIG. 8 is a schematic structural diagram of another single-photon avalanche diode provided by an embodiment of the present application.
  • FIG. 9 is a schematic structural diagram of yet another single-photon avalanche diode in an embodiment of the present application.
  • Fig. 10 is the projection schematic diagram of each component in the horizontal plane in Fig. 9;
  • FIG. 11 is a schematic structural diagram of another single-photon avalanche diode provided by an embodiment of the present application.
  • FIG. 12 is a schematic structural diagram of yet another single-photon avalanche diode provided by an embodiment of the application.
  • FIG. 13 is a flowchart of a method for manufacturing a single-photon avalanche diode according to an embodiment of the present application.
  • Embodiments of the present application provide a semiconductor device, a manufacturing method thereof, a light detection device and a system, which can improve light detection efficiency.
  • the single-photon avalanche diode is used as a component of a photodetector. Its working principle is to generate photo-generated carriers under the action of optical signals through the photoelectric effect, which are rapidly accelerated when moving in a high electric field region, and may occur during the movement. One or more collisions generate secondary and tertiary new electron-hole pairs through the impact ionization effect, resulting in an avalanche multiplication effect, which rapidly increases the number of carriers, thereby generating a relatively large photo-generated current.
  • the inventor found that the light detection efficiency of a single-photon avalanche diode is determined by its quantum efficiency for target photons and its own avalanche probability, and the quantum efficiency of a single-photon avalanche diode for target photons is usually equal to its high field region. There is a trade-off between the quantum efficiency and avalanche probability of current single-photon avalanche diodes, and the two cannot be optimized at the same time, resulting in limited light detection efficiency.
  • the current single-photon avalanche diode utilizes the avalanche breakdown of the PN junction, which may occur at the edge or the center flat region of the PN junction. If the avalanche breakdown occurs at the edge, the avalanche probability is high, but high The field area is small. If the avalanche breakdown occurs in the central flat area, the high field area is larger, but the avalanche probability is low.
  • FIG. 1 is a schematic diagram of the structure of a current single-photon avalanche diode
  • an N+ well region is arranged on the upper surface of the P-type well, and the contact region between the P-type well and the N+ well region serves as a high-field region, and the avalanche effect also occurs.
  • the avalanche effect will occur at the edge position first, and it is obvious that the quantum efficiency is low at this time.
  • the upper surface of the P-type well may also be provided with a P+ well region, and the P+ well region and the N+ well region may be biased to promote the occurrence of the avalanche effect.
  • the single-photon avalanche diode may include a first doping material layer, a second doping structure, a A doped structure and a cover material, wherein the first doped material layer and the second doped structure are stacked in the longitudinal direction, and the cross section of the second doped structure is smaller than the first doped material layer, the first doped material layer and the The doping types of the second doping structure are the same, the doping concentration of the second doping structure is higher than that of the first doping material layer, and the first doping structure is located between the second doping structure and the first doping material layer , and cover the sidewall of the second doping structure, the doping type of the first doping structure is opposite to that of the second doping structure, and the adjacent areas of the first doping structure and the second doping structure are used for An avalan
  • the first doping structure is formed on one side of the horizontal surface and the sidewall of the second doping structure, and the region adjacent to the first doping structure and the second doping structure is used for forming Avalanche region, and the high field region of the corner region adjacent to the second doping structure and the first doping structure is more likely to form an avalanche region, that is, the avalanche effect occurs in the edge region of the second doping structure and the first doping structure.
  • the cover material can provide an electric field that makes the multiple carriers in the first doped material layer move from the edge to the center, which is beneficial to the photogenerated carriers in the first doped material layer to the avalanche region. Therefore, the charge collection efficiency is improved to a certain extent, so the device has a high quantum efficiency, which can have a high photodetection efficiency.
  • the light detection system may include a light emission device and a light detection device, wherein the light emission device is used to emit light signals to the object to be measured,
  • the light detection device can be used to generate an avalanche current based on the light signal reflected by the object to be tested.
  • the time of flight of the optical signal can be determined by using the time point when the optical signal is emitted to the object to be measured and the time point when the avalanche current is generated, so the distance between the object to be measured and the optical detection system can be calculated.
  • the light emitting device can be a laser array, and there can be a collimating lens between the light emitting device and the object to be measured;
  • the light detection device can include a plurality of light detection units, the light detection units can be arranged in an array, and there can be a Filters that transmit light of specified wavelengths, such as infrared light.
  • the light detection units can be isolated by isolation trenches, thereby reducing cross talk (X-talk) between different single-photon avalanche diodes.
  • the isolation trench may be a deep trench
  • the isolation method may be a deep trench isolation (DTI) process.
  • the isolation trench can divide the light detection device into a plurality of light absorption regions, the single photon avalanche diode can be formed in the light absorption region, and the single photon avalanche diode can generate an avalanche current based on the optical signal of the light absorption region to which it belongs,
  • Each light absorbing area can be arranged in an array, and the shape of the light absorbing area can be determined according to the actual situation, for example, it can be a polygon that can be closely arranged.
  • insulating materials can be filled to realize the isolation of different single-photon avalanche diodes; in the isolation trench, a dielectric layer can also be formed on the sidewall, and then the isolation trench can be filled with metal fillers , the isolation of different single-photon avalanche diodes can also be achieved.
  • the dielectric layer may be a high dielectric constant (high K) material, such as Al 2 O 3 , TaO, HfO, etc., and the metal filling layer may be metal tungsten, for example.
  • the insulating material or dielectric layer can reduce the dark count of the single-photon avalanche diode, that is, reduce the avalanche current generated in the absence of an optical signal, and can reduce the leakage of the single-photon avalanche diode at the same time.
  • the metal filling layer is usually an opaque material, which can reduce the interference of optical signals between different single-photon avalanche diodes.
  • FIG. 3 a schematic structural diagram of a light detection unit provided in an embodiment of the present application, wherein the light detection unit may include a logic circuit layer and a single-photon avalanche diode, and the logic circuit layer may include an image signal processor (image signal processor) , ISP) unit, which can process the avalanche current.
  • ISP image signal processor
  • the number of photons that generate the avalanche current can be calculated according to the change of the avalanche current.
  • the photogenerated carriers move and amplify under the action of the electric field to obtain the avalanche current.
  • the logic circuit layer and the single-photon avalanche diode can be arranged on different layers of the same substrate.
  • the logic circuit layer can be arranged between the substrate and the single-photon avalanche diode to form a back-illuminated structure of the light detection device, as shown in FIG. 3B
  • the logic circuit layer can also be arranged on the substrate, and is arranged on the same layer as the single-photon avalanche diode thereon to form an orthographic structure of the light detection device, as shown in FIG.
  • the logic circuit layer may further include a control unit, and the control unit may control the working state of the light detection unit, for example, control the input voltage of the light detection unit.
  • the control unit and the image signal processor can be arranged in the same layer or in different layers.
  • the light emitting device may also be provided with a control circuit for controlling the light emitting device to emit light signals.
  • the single-photon avalanche diode may include a first doping material layer 110 , a second doping structure 120 and a first doping structure.
  • the first doping material layer 110 and the second doping structure 120 may be stacked in the longitudinal direction, and the cross section of the second doping structure 120 may be smaller than the first doping material layer 110.
  • the first doping material layer 110 may be located in the The top of the second doping structure 120 may also be located below the second doping structure 120 .
  • the second doping structure 120 is above the first doping material layer 110 as an example for illustration.
  • the doping types of the first doping material layer 110 and the second doping structure 120 are the same, for example, both are P-type doping or both are N-type doping, and the doping concentration of the second doping structure 120 is higher than that of the first doping Doping concentration of the impurity material layer 110 .
  • different doping may be classified into heavy doping, doping, and light doping according to the level of doping concentration, so as to correspond to different doping concentration ranges respectively, wherein the heavy doping may be It is represented by P+ or N+, doping can be represented by P or N, and light doping can be represented by P- or N-.
  • the first doping material layer 110 may be shallowly doped
  • the doping type may be represented by P- or N-
  • the second doping structure 120 may be heavily doped
  • the doping type may be represented by P+ or N+.
  • the cross section of the first doping material layer 110 may be polygonal, such as a rectangle, a triangle, a hexagon, etc.
  • the second doping structure 120 may be located in the middle of the first doping material layer 110, or may be along the first doping material layer 110.
  • the edge of the dopant material layer may be disposed at the top corner of the first dopant material layer.
  • the single-photon avalanche diode may further include a first doping structure, and the first doping structure may cover the surface of the second doping structure 120 facing the first doping material layer 110 and cover the second doping structure
  • the sidewalls of 120 that is to say, when the first doping material layer 110 is located above the second doping structure 120, the first doping structure may be located on the upper surface and sidewalls of the second doping structure 120.
  • the first doping structure may be located on the lower surface and sidewalls of the second doping structure 120 .
  • the doping type of the first doping structure is opposite to that of the first doping material layer 110 , and the doping types of the first doping material layer 110 and the second doping structure 120 are the same, so the doping type of the first doping structure is the same Different from the second doping structure 120 and the first doping material layer 110 .
  • the first doping material layer 110, the first doping structure and the second doping structure 120 can form a PNP or NPN structure, which is easily formed in the adjacent corner regions of the second doping structure 120 and the first doping structure In the avalanche region 122 , the carriers can enter the second doping structure 120 through the first doping structure in the corner region, wherein the size of the avalanche region 122 is determined according to the actual situation, and the drawing is only one example.
  • the first doping structure may include a first part 111 and a second part 112 that are connected to each other, the first part 111 extends longitudinally in the first doping material layer 110 and is opposite to the second doping structure 120 , and the second part 112 covers the sidewall of the second doping structure 120 and the corner region formed by the surface of the second doping structure 120 facing the first doping material layer 110 .
  • the second portion 112 in the first doping structure may cover the entire sidewall of the second doping structure 120, or may cover only a portion of the sidewall of the second doping structure 120 close to the first doping material layer 110, or may cover the sidewall of the second doping structure 120.
  • One sidewall, or multiple sidewalls may cover the entire horizontal surface of the second doping structure 120 near the first doping material layer 110, or only cover the second doping structure 120 near the first doping material layer 110.
  • the edge region of the horizontal surface of the miscellaneous material layer 110 may cover the entire sidewall of the second doping structure 120, or may cover only a portion of the sidewall of the second doping structure 120 close to the first doping material layer 110, or may cover the sidewall of the second doping structure 120.
  • the second portion 112 of the first doping structure may have a groove in which the second doping structure 120 is embedded, and the groove may be a penetrating groove or a non-penetrating groove. groove.
  • the second part 112 of the first doping structure includes a through groove, the first part 111 of the first doping structure can be embedded in the groove of the second part 112 so as to be connected with the second part 112.
  • the first The dimension of the second portion 112 of a doping structure in the horizontal plane is smaller than that of the first portion 111; when the second portion 112 of the first doping structure includes a non-penetrating groove, the first portion 111 of the first doping structure may The side of a doping structure away from the second doping structure 120 is connected to the second part 112 of the first doping structure. At this time, the dimension of the second part 112 of the first doping structure in the horizontal plane may be smaller than that of the first part 111, which can also be equal to the first part 111, or larger than the first part 111.
  • the longitudinal extension length of the first portion 111 in the first doping structure can be determined according to the actual situation, for example, it can extend to the middle of the first doping material layer 110, or it can longitudinally penetrate the first doping material layer 110, referring to FIG. 4 . shown.
  • the doping concentrations of the first portion 111 and the second portion 112 in the first doping structure may or may not be consistent.
  • the doping type of the first portion 111 in the first doping structure is inconsistent with the doping type of the first doping material layer 110, so the electric field inside the first doping material layer 110 will be changed, so that the first doping material layer 110 will be changed.
  • the photo-generated carriers in 110 move in a direction away from the first doping structure 111 , which is favorable for the photo-generated carriers to move to the position of the avalanche region, which is favorable for carrier collection. And the longer the longitudinal extension of the first part 111 is, the more favorable it is for the movement of carriers.
  • a voltage may be applied to the second doping structure 120 and the first doping material layer 110 so that there is a voltage difference between the two.
  • the second doping structure 120 can be used as a second lead-out terminal
  • the first doping material layer 110 can be connected 143 to the first lead-out end
  • the first lead-out end 143 and the second lead-out terminal can be used to apply a deviation to the single-photon avalanche diode, thereby
  • the working state of the single-photon avalanche diode is controlled, for example, by setting the bias voltage of the first terminal 143 and the second terminal, so that the single-photon avalanche diode works in the Geiger mode, so that the avalanche effect occurs under the illumination of light.
  • the avalanche current can also be detected by using the second doping structure 120, so as to analyze the avalanche current, for example, using the avalanche current to analyze the optical signal causing the avalanche current.
  • FIG. 5 is a schematic diagram of another single-photon avalanche diode provided by an embodiment of the present application
  • FIG. 5A is an NPN structure, that is, the doping type of the first doping material layer 110 is N- , the doping type of the first doping structure is P, the doping type of the second doping structure 120 is N+, and the majority of electrons in the first doping material layer 110 are electrons
  • the photogenerated carriers are also basically 5B is a PNP structure, that is, the doping type of the first doping material layer 110 is P-, the doping type of the first doping structure is N, the doping type of the second doping structure 120 is P+, and the doping type of the second doping structure 120 is P+.
  • Many carriers in a doped material layer 110 are holes, so the photogenerated carriers are basically holes.
  • the second doping structure 120 may be represented as an ellipse, a circle, a polygon, etc. in the lateral direction.
  • the second portion 112 of the first doping structure may be embodied as an elliptical ring, a circular ring, a Polygon rings, etc.
  • FIG. 6 which is a schematic diagram of the projection of the second doping structure and the first doping structure in the horizontal plane in the embodiment of the present application, as shown in FIG. 6A , the second doping structure 120 forms a circle in the lateral direction, and the first doping structure 120 A doping structure appears as a circular ring in the lateral direction; with reference to FIG.
  • the second doping structure 120 forms a rectangle in the lateral direction, and the first doping structure appears as a rectangular ring in the lateral direction, wherein the rectangular ring may include corners, Rounded or chamfered corners;
  • the second doping structure 120 may form a triangle in the lateral direction, and the first doping structure may be a triangular ring in the lateral direction, wherein the triangular ring may include corners, rounded corners or beveled corners Cut corners;
  • the second doping structure 120 may form a hexagon in the lateral direction, and the first doping structure may be a hexagonal ring in the lateral direction, wherein the hexagonal ring may include corners, rounded corners or chamfered corners.
  • the single-photon avalanche diode may further include a covering material, and the covering material is formed on the surface of the first doping material layer 110 .
  • the covering material may include a covering material formed on the first doping material layer 110 away from the second doping material layer 110 .
  • the covering material can also provide an electric field for moving the carriers in the first doping material layer 110 from the edge to the center, so the covering material can promote the movement of carriers from the edge to the center, thereby improving the charge collection efficiency.
  • the first doped material layer 110 can be connected to the first terminal by using a covering material, so as to apply a bias voltage to the single-photon avalanche diode.
  • FIG. 7 is a schematic diagram of an equipotential line provided by an embodiment of the present application, specifically, a schematic diagram of an equipotential line inside the single-photon avalanche diode shown in FIG. 5A , wherein the upper center position is the second doping
  • the position of the structure 120, the lower center position is the position of the first part 111 of the first doping structure, and the covering material includes the first material, the second material and the third material.
  • the equipotential lines form a symmetrical structure
  • the equipotential lines go inward from the outer layer, and the potential gradually increases, so the direction of the electric field lines is directed from the second doping structure 120 to the center position of the cover material and the first part 111 of the first doping structure, and then from the center position to the cover material and the first part 111 of the first doping structure (the opposite direction of the dashed arrow in the figure), so the electrons in the first doped material layer move against the direction of the electric field line, referring to the direction of the dashed arrow in the figure, so as to dope the second Structure 120 moves.
  • the cover material may be a fourth doping structure, wherein the doping type of the fourth doping structure is opposite to the doping type of the first doping material layer 110 , for example, the doping type of the first doping material layer 110 is N -, the doping type of the fourth doping structure can be P, at this time, the electric field direction is directed from the first doping material layer 110 to the fourth doping structure, so the electrons in the first doping material layer 110 act as multiple electrons, The electrons at the edge move to the middle of the first doping material layer 110 under the action of the electric field generated by the fourth doping structure.
  • the doping type of the first doping structure is opposite to that of the first doping material layer 110 , when the doping type of the first doping material layer 110 is N-, the doping type of the first doping structure can also be P, at this time, the direction of the electric field is directed from the first doping material layer 110 to the first doping structure, and the electrons around the first doping structure will be far away from the first doping structure under the action of the electric field. Therefore, the final electrons will move towards the first doping structure. Aggregation between a doped structure and a fourth doped structure.
  • the cover material may also be a dielectric layer, the dielectric layer has charges, and the charging type of the dielectric layer is the same as the charging type of the multi-subs in the first doping material layer 110 , for example, the doping type of the first doping material layer 110
  • the type is N-, in which electrons are multi-subs, the dielectric layer can be negatively charged, and an electric field directed from the first doping material layer 110 to the dielectric layer is generated. Therefore, under the action of the electric field generated by the charged dielectric layer, the dielectric layer is located at the edge position
  • the electrons in the first dopant material layer 110 move toward the middle of the first dopant material layer 110 .
  • the electric field generated by the first doping structure drives electrons away from the first doping structure, and the final electrons will gather between the first doping structure and the dielectric layer.
  • the cover material may also include the fourth doping structure and the dielectric layer at the same time, wherein the dielectric layer may be located outside the fourth doping structure, and the charged dielectric layer may also be located on the same layer as the fourth doping structure.
  • the first material 1411 located on the surface of the first doping material layer 110 away from the second doping structure 120 is the fourth doping structure, and the first doping material layer 110 is provided with the second doping structure
  • the third material 1413 on the surface of 120 and the second material 1412 on the sidewall of the first doping material layer 110 are dielectric layers, or, the first material 1411 and the second material 1412 are dielectric layers, and the third material 1413 is The third doping structure.
  • the cover material may surround the first doping material layer 110, and the setting position may be on the surface of the first doping material layer 110.
  • the first doping material layer 110 in the single-photon avalanche diode also For array distribution, the first dopant material layers 110 in different single-photon avalanche diodes can be separated by longitudinal isolation trenches, and the capping material is located on the surface of the first dopant material layer and thus adjacent to the isolation trenches, At this time, the covering material may be formed on the inner sidewall of the isolation trench, or may surround the isolation trench. . That is, the fourth doping structure and/or the dielectric layer may form the inner sidewall of the isolation trench 140 , or may be formed on the periphery of the isolation trench 140 .
  • a dielectric layer can be formed on the sidewall, and then the isolation trench 140 can be filled with a metal filler 142, and the isolation of different single-photon avalanche diodes can also be realized.
  • the dielectric layer here is a charged dielectric layer, which is formed on the sidewall of the first doping material layer 110.
  • the charged dielectric layer can also provide an electric field for moving the multiple electrons in the first doping material layer 110 from the edge to the center, When the charged dielectric layer is formed on the sidewall of the isolation trench 140 , it can be used as a covering material, and can also form a covering material together with the fourth doping structure.
  • the first doping material layer 110 can be connected to the first lead-out end 143 through the cover material, so in practice, the first lead-out end 143 and the second lead-out end (ie, the second doping structure 120 ) can be arranged on the same layer, It is convenient to bias both.
  • the first lead-out terminal 143 may be a doped material, and its doping type is different from that of the second doping structure 120, and its doping is also heavily doped, which may be represented by P+ or N+.
  • the first lead-out end 143 and the second lead-out end may also be connected with an interconnection line 133, and the interconnection line 133 may be made of a metal material.
  • the connection line 133 can be made of transparent electrode material, so as to improve the transmittance of light.
  • the interconnection lines 133 may be disposed in the capping layer 134, as shown in FIG. 11 .
  • a third doping structure 121 is formed between the second doping structure 120 and the covering material, which can reduce the horizontal surface potential gradient where the second doping structure 120 and the first doping structure are located, thereby reducing leakage.
  • the single-photon avalanche diode may further include a third doping structure 121, the doping type of the third doping structure 121 is the same as that of the second doping structure 120, and the doping concentration is lower than that of the second doping structure 121.
  • Heterostructure 120 When the second portion 112 of the first doping structure is located at a part of the sidewall of the second doping structure 120 close to the first doping material layer 110 , the third doping structure 121 may be located in the second doping structure 120 not covered by the second doping structure 120 . A part of the sidewall covered by a doping structure, at this time, the second doping structure 120 and the first doping structure can be in direct contact.
  • FIG. 8 another single photon avalanche provided by this embodiment of the present application is provided.
  • a schematic diagram of the structure of a diode, the existence of the third doping structure 121 can reduce the horizontal surface potential gradient where the second doping structure 120 and the first doping structure are located, and the third doping structure 121 can also be located between the second doping structure 120 and the first doping structure.
  • the third doping structure 121 may be simultaneously located between the second doping structure 120 and the first doping structure Part of the sidewall covered by the doping structure, and between the second doping structure 120 and the first doping structure, that is, the third doping structure 121 may cover the entire sidewall of the second doping structure 120, and the second doping structure
  • the structure 120 is close to the horizontal surface of the first dopant material layer 110 , as shown with reference to FIG. 4 .
  • the third doping structure 121 may be located on the sidewall of the second doping structure 120, or may be located on the sidewall of the second doping structure 120 and between the second doping structure 120 and the first doping structure, At this time, the presence of the third doping structure 121 will not affect the position of the avalanche region and the avalanche probability between the second doping structure 120 and the first doping structure, and the avalanche region is still located between the first doping structure and the second doping structure.
  • the adjacent corner positions of the doped structures are not affect the position of the avalanche region and the avalanche probability between the second doping structure 120 and the first doping structure, and the avalanche region is still located between the first doping structure and the second doping structure.
  • the lateral thickness of the third doping structure 121 located on the sidewall of the second doping structure 120 may be determined according to actual conditions. When the third doping structure 121 is located at a part of the sidewall of the second doping structure 120 that is not covered by the first doping structure, the lateral thickness of the third doping structure 121 can be appropriately increased to effectively reduce the second doping structure 120 and the horizontal surface potential gradient where the first doped structure is located.
  • the cross section of the first doping material layer 110 may be polygonal, such as a rectangle, a triangle, a hexagon, etc.
  • the second doping structure 120 may be located in the middle of the first doping material layer 110, or may be along the first doping material layer 110.
  • the edge of the dopant material layer may be disposed at the top corner of the first dopant material layer.
  • the second doping structure 120 is located in the middle of the first doping material layer 110 .
  • the second doping structure 120 may be disposed at the top corner of the first doping material layer position, wherein, FIG. 9 is a schematic structural diagram of another single-photon avalanche diode in the embodiment of the application, and FIG.
  • the second doping structure and the first doping structure can be located at the upper right corner of the first doping material layer, the isolation trench 140 separates different first doping material layers, the cover material is formed on the periphery of the isolation trench, and is connected to the first lead-out end 143, the first
  • the cross section of the second doping structure 120 is a quarter circle, and the third doping structure 121 and the first doping structure are quarter circles.
  • the electric field generated by the cover material makes the first doping material layer 110
  • the photo-generated carriers generated in the middle move from the edge to the center, and the electric field between the second doping structure 120, the third doping structure 121, the first doping structure and the first doping material layer 110 causes the photo-generated carriers to move toward the center.
  • the second doping structure 120 moves and an avalanche current is formed.
  • the second doping structure 120 may also be disposed along one side of the rectangular first doping material layer.
  • the second doping structure 120 may be a half circle, and the third doping structure 121 and The first doping structure is a half ring, which is not illustrated here.
  • the first doping material layers located in different light detection units may be separated by isolation trenches, and at this time, a bias voltage may also be applied to the metal filling layer 142 in the isolation trench 140, thereby accelerating Collection of photogenerated carriers.
  • a bias voltage may also be applied to the metal filling layer 142 in the isolation trench 140, thereby accelerating Collection of photogenerated carriers.
  • a negative bias voltage may be applied to the metal filling layer 142
  • the doping type of the first doping material layer 110 is P-, it may be The metal fill layer 142 is positively biased.
  • the single-photon avalanche diode may further include a substrate 100, and the second doping structure 120, the first doping structure and the first doping material layer 110 described above may be disposed on the substrate 100, because
  • the photodetection devices are classified into two types: front-illuminated (FSI) and back-illuminated (BSI), so the stacking methods on the substrate 100 are also different.
  • the light detection device can include a single-photon avalanche diode and a logic circuit layer.
  • the logic circuit layer can be located on the same layer as the single-photon avalanche diode.
  • the logic circuit layer is located under the single-photon avalanche diode, and the light directly illuminates the single-photon avalanche diode, and the logic circuit layer will not block the light beam.
  • FIG. 11 is a schematic structural diagram of yet another single-photon avalanche diode provided in an embodiment of the present application.
  • the second doping structure 120 of the single-photon avalanche diode can be disposed upward, and the interconnect layer 133 is disposed above the second doping structure 120,
  • the interconnection layer 133 may be disposed in the dielectric layer 134 .
  • the substrate 100 can be provided with the first doping material layer 110 , the first doping structure and the In the second doping structure 120, at this time, the interconnection layer 133 on the second doping structure 120 may be a transparent metal material to reduce the absorption of light.
  • the second doping structure 120 of the single-photon avalanche diode can be disposed downward, and the interconnect layer 133 can be disposed below the second doping structure 120 , for realizing the interconnection between the single-photon avalanche diode and the logic circuit layer, the interconnection layer 133 may be arranged in the dielectric layer 134 .
  • the light is directly incident on the first doping material layer 110 from top to bottom, and does not need to pass through the substrate 100 , that is, the substrate 100 can be provided with the second doping structure 120 , the first doping structure and the first doping structure from bottom to top. Doping material layer 110 .
  • the substrate 100 may be an insulating substrate or a semiconductor substrate.
  • an insulating layer may be formed on the surface of the substrate 100, so as to separate the substrate 100 and other films on it. The layers are separated to avoid the influence of the carrier avalanche current generated by the substrate 100, so the dark count can be reduced.
  • the substrate 100 is an insulator, and the second doping structure 120 , the first doping structure and the third doping structure 121 thereon are doped silicon materials, thereby forming a silicon on insulator (SOI) )structure.
  • SOI silicon on insulator
  • the single-photon avalanche diode in this embodiment of the present application may further include a microlens layer 150.
  • the microlens layer 150 may be located on a surface away from the substrate 100, and the microlens layer 150 may be used to focus the optical signal, thereby Concentrate the optical signal in a location prone to avalanche effects.
  • FIG. 12 which is a schematic structural diagram of another single-photon avalanche diode provided by an embodiment of the present application, wherein FIG. 12A is a front-illuminated structure, and the microlens layer 150 is disposed on the second doping structure 120 . Shown as a backside illuminated structure, the microlens layer 150 is disposed on the first doped material layer 110 .
  • the substrate 100 is an insulating substrate.
  • the focusing position of the microlens layer 150 is in the middle between the edge of the first doping material layer 110 and the second doping structure 120, so that the light beam can be focused to the first doping structure and the first doping structure 120.
  • the position between the edges of the doping material layer 110 can improve the carrier collection efficiency.
  • the microlens layer may include microlenses arranged in an array, and the microlenses may be convex lenses and/or Fresnel lenses, wherein the Fresnel lenses and the convex lenses can achieve the same focusing effect, and can have smaller
  • the vertical size is conducive to reducing the size of the device.
  • the arrangement position thereof can be determined according to the shape of the second doping structure 120 , and the arrangement quantity thereof can be determined according to the actual situation.
  • an anti-reflection layer can also be provided to increase the quantum efficiency of the target light.
  • the single-photon avalanche diode may further include an inverted pyramid structure 151, the inverted pyramid structure 151 may be an inverted pyramid structure array (inverted pyramid array, IPA), and the inverted pyramid structure 151 is located on a side away from the substrate 100, It is used for refraction when the light passes through, thereby changing the transmission direction of the light, so that the light is not only transmitted in the vertical direction in the first doping material layer 110, thus increasing the transmission path of the light and increasing the first doping material layer 110 absorbs light to generate carriers.
  • inverted pyramid structure 151 may be an inverted pyramid structure array (inverted pyramid array, IPA)
  • the inverted pyramid structure 151 is located on a side away from the substrate 100, It is used for refraction when the light passes through, thereby changing the transmission direction of the light, so that the light is not only transmitted in the vertical direction in the first doping material layer 110, thus increasing the transmission path of the light and increasing the first doping material layer 110 absorbs light to generate carriers.
  • the structure in the inverted pyramid structure 151 has a plurality of planes that are not parallel to the surface of the substrate, and the refractive index of the inverted pyramid structure can be different from the refractive index of the film layers above or below it, so that light is refracted and changed when passing through. direction of light transmission.
  • the inverted pyramid structure may be obtained by etching and filling the first doping material layer, or may be obtained by etching and filling the cover material.
  • the inverted pyramid structure 151 may be located between the microlens layer 150 and the film layer below it, so that light is focused and refracted, for example, between the microlens layer 150 and the third material 1413 of the sidewall of the second doping structure 120 , the inverted pyramid structure 151 can be obtained by etching and filling the third material 1413 under it, and a flat layer 152 can be provided on the inverted pyramid structure 151 to facilitate the formation of the upper film layer, as shown in FIG. 12A , Alternatively, the inverted pyramid structure 151 may be located between the microlens layer 150 and the first doping material layer 110, and the inverted pyramid structure 151 may be obtained by etching and filling the first material 1411 under the inverted pyramid structure 151. A planarization layer 152 may be formed, as shown with reference to FIG. 12B.
  • the inverted pyramid structure 151 is located in the cover material. If the cover material is a charged dielectric layer, the first doping material layer 110 may be etched first to obtain the inverted pyramid structure. If a charged dielectric layer is formed on the inverted pyramid structure, the first doping material layer 110 may not be doped to form a fourth doping structure.
  • Embodiments of the present application provide a single-photon avalanche diode, including a first doping material layer, a second doping structure, a first doping structure and a cover material, wherein the first doping material layer and the second doping structure are Stacked vertically, the cross section of the second doping structure is smaller than that of the first doping material layer, the doping types of the first doping material layer and the second doping structure are the same, and the doping concentration of the second doping structure is high In the first doping material layer, the first doping structure is located between the second doping structure and the first doping material layer, and covers the sidewall of the second doping structure, the doping of the first doping structure The type is opposite to that of the second doping structure, and a region adjacent to the first doping structure and the second doping structure is used to form an avalanche region, and a cover material is formed on the surface of the first doping material layer to provide the first doping structure.
  • the first doping structure is formed on one side of the horizontal surface and the sidewall of the second doping structure, and the region adjacent to the first doping structure and the second doping structure is used for forming Avalanche region, and the high field region of the corner region adjacent to the second doping structure and the first doping structure is more likely to form an avalanche region, that is, the avalanche effect occurs in the edge region of the second doping structure and the first doping structure.
  • the cover material can provide an electric field that makes the multiple carriers in the first doped material layer move from the edge to the center, which is beneficial to the photogenerated carriers in the first doped material layer to the avalanche region. Therefore, the charge collection efficiency is improved to a certain extent, so the device has a high quantum efficiency, which can have a high photodetection efficiency.
  • an embodiment of the present application further provides a method for manufacturing a single-photon avalanche diode.
  • a method for manufacturing a single-photon avalanche diode provided by an embodiment of the present application is provided. Specifically, the method may include the following steps:
  • the substrate can be an insulating substrate or a semiconductor substrate.
  • an insulating layer can be formed on the surface of the substrate, so as to isolate the substrate from other film layers on it and avoid the lining of the substrate.
  • the carrier avalanche current generated at the bottom has an influence, so the dark count can be reduced.
  • the cross section of the second doping structure is smaller than that of the first doping material layer, the doping types of the first doping material layer and the second doping structure are the same, and the doping concentration of the second doping structure is higher than that of the first doping structure
  • the first doping structure is located between the second doping structure and the first doping material layer, and covers the sidewall of the second doping structure
  • the doping type of the first doping structure is the same as that of the second doping structure
  • a region adjacent to the first doping structure and the second doping structure is used to form an avalanche region, and a covering material is formed on the surface of the first doping material layer, which is used to provide the first doping material layer.
  • the first doping material layer, the first doping structure and the second doping structure may be doped silicon materials.
  • the second doping structure, the first doping structure and the first doping material layer may be sequentially formed on the substrate from bottom to top. After that, an interconnection layer interconnecting with the logic circuit layer and a logic circuit located on the same layer as the single-photon avalanche diode can be formed on the second doping structure, thereby forming a light detection unit.
  • the logic circuit can also be formed in a single-photon avalanche diode. photonic avalanche diodes are formed before.
  • a bulk structure can be formed on the substrate, and the bulk structure is sequentially doped to form a first doping material layer, a third doping material, and a second doping structure.
  • the bulk structure can be an intrinsic layer or a Lightly doped layer.
  • the lightly doped layer may be the bulk structure of the first doped material layer, and the first doped structure and the second doped structure are formed by doping in the bulk structure of the first doped material layer, and the lightly doped layer is also It can be other material layers, and the first doped material layer, the first doped structure and the second doped structure are obtained by doping.
  • the first doping material layer, the third doping material, and the second doping structure can also be sequentially formed on the substrate by means of epitaxial growth.
  • the bulk structure of the first doping material layer 110 may be formed on the substrate first, where the bulk structure includes the first doping structure and the second doping structure. Structure 120, location of cover material. After that, the bottom of the bulk structure can be counter-doped to obtain the first material 1411 in the covering material on the bottom surface of the first doping material layer 110, and then the sidewalls of the bulk structure can be counter-doped to obtain the first material 1411 located on the bottom surface of the first doping material layer 110.
  • the second material 1412 in the covering material of the sidewall of a doped material layer 110 can be counter-doped in the middle of the bulk structure to obtain the first part 111 and the second part 112 of the first doped structure. Doping is performed on the upper portion of the bulk structure to form the second doping structure 130, and counter-doping is performed to form the third material 1413 in the capping material.
  • the second doping structure, the first doping structure and the first doping material layer may be sequentially formed on the substrate from bottom to top.
  • a logic circuit layer and a dielectric layer covering the logic circuit layer may have been formed on the substrate, and the second doping structure may be formed on the dielectric layer covering the logic circuit layer.
  • an interconnection layer interconnected with the logic circuit layer may also be formed, and the interconnection layer is used to connect the second doping structure and the logic circuit layer.
  • a bulk structure can be formed on the substrate, and the bulk structure is sequentially doped to form a second doping structure, a first doping structure, and a first doping material layer.
  • the bulk structure can be an intrinsic layer or a Lightly doped layer.
  • the lightly doped layer can be a first doped material layer, the first doped structure and the second doped structure are formed by doping in the first doped material layer, and the lightly doped layer can also be other material layers,
  • the first doping material layer, the first doping structure and the second doping structure are obtained by doping.
  • the second doping structure, the first doping structure and the first doping material layer can also be sequentially formed on the substrate by means of epitaxial growth.
  • a bulk structure of the first doping material layer 110 may be formed on the substrate first, where the bulk structure includes the first doping structure and the second doping structure. Structure 120, location of cover material.
  • doping can be performed heavily at the bottom of the bulk structure to form the second doping structure 120, and counter-doping can be performed to form the third material 1413 in the covering material; after that, counter-doping can be performed in the middle of the bulk structure , obtaining the first part 111 and the second part 112 of the first doping structure, and performing counter-doping on the sidewall of the bulk structure to obtain the second material 1412 located in the covering material of the sidewall of the first doping material layer 110; Afterwards, the upper portion of the bulk structure may be counter-doped to obtain the first material 1411 in the capping material on the bottom surface of the first doped material layer 110 .
  • the single-photon avalanche diode may further include a cover material, and the cover material may be formed on the surface of the first doping material layer.
  • the cover material may be formed on the surface of the first doping material layer away from the second doping structure. the surface, and/or the sidewalls of the first dopant material layer, and/or the sidewalls of the second dopant material layer.
  • the covering material can also provide an electric field for moving the carriers in the first doping material layer from the edge to the center, so the covering material can promote the movement of carriers from the edge to the center, thereby improving the charge collection efficiency.
  • the first doping material layer can be connected to the first terminal by using a covering material, so as to apply a bias voltage to the single-photon avalanche diode.
  • the cover material may be a fourth doping structure, wherein the doping type of the fourth doping structure is opposite to the doping type of the first doping material layer, for example, the doping type of the first doping material layer is N-, Then the doping type of the fourth doping structure can be P.
  • the direction of the electric field is directed from the first doping material layer to the fourth doping structure, so the electrons in the first doping material layer are multi-subs, and the electrons in the edge are in the Under the action of the electric field generated by the fourth doping structure, it moves to the middle of the first doping material layer.
  • the doping type of the first doping structure is opposite to that of the first doping material layer, when the doping type of the first doping material layer is N-, the doping type of the first doping structure may also be P, At this time, the direction of the electric field is directed from the first doping material layer to the first doping structure, and the electrons around the first doping structure will move away from the first doping structure under the action of the electric field. Therefore, the final electrons will be doped toward the first doping structure. between the structure and the fourth doped structure.
  • the cover material can also be a dielectric layer, the dielectric layer is charged, and the charging type of the dielectric layer is the same as the charging type of the multi-subs in the first doping material layer, for example, the doping type of the first doping material layer is N-, in which electrons act as multi-subs, the dielectric layer can be negatively charged, and an electric field directed from the first doping material layer to the dielectric layer is generated. Electrons in the dopant material layer move toward the middle of the first dopant material layer. The electric field generated by the first doping structure drives electrons away from the first doping structure, and the final electrons will gather between the first doping structure and the dielectric layer.
  • the cover material may also include the fourth doping structure and the dielectric layer at the same time, wherein the dielectric layer may be located outside the fourth doping structure, and the charged dielectric layer may also be located on the same layer as the fourth doping structure.
  • the first material 1411 located on the surface of the first doping material layer 110 away from the second doping structure 120 is the fourth doping structure, and the first doping material layer 110 is provided with the second doping structure
  • the third material 1413 on the surface of 120 and the second material 1412 on the sidewall of the first doping material layer 110 are dielectric layers, or, the first material 1411 and the second material 1412 are dielectric layers, and the third material 1413 is The third doping structure.
  • the cover material can surround the first doping material layer, and its setting position is on the surface of the first doping material layer.
  • the first doping material layer in the single-photon avalanche diode is also distributed in an array.
  • the first dopant material layers in different single-photon avalanche diodes can be separated by longitudinal isolation trenches, and the cover material is located on the surface of the first dopant material layer, so it is adjacent to the isolation trenches.
  • the cover material It can be formed on the inner sidewall of the isolation trench, or can surround the isolation trench. That is, the fourth doping structure and/or the charged dielectric layer may form the inner sidewall of the isolation trench, or may be formed on the outer periphery of the isolation trench.
  • the cover material can be formed by doping or epitaxial growth. For example, doping can be performed at the edge of the first doping material layer to obtain a fourth doping structure surrounding the remaining first doping material layer, or the first doping material layer can be etched to form an isolation trench, A charged dielectric layer is epitaxially formed on the sidewalls of the isolation trenches.
  • a third doping structure may also be formed.
  • the doping type of the third doping structure 121 is the same as that of the second doping structure 120 , and the doping concentration is lower than that of the second doping structure 120 .
  • the third doping structure 121 may be located in the second doping structure 120 not covered by the second doping structure 120 .
  • the second doping structure 120 and the first doping structure can be in direct contact, and the existence of the third doping structure 121 can reduce the amount of the second doping structure 120 and the first doping structure
  • the horizontal surface potential gradient where the doping structure is located, the third doping structure 121 may also be located between the second doping structure 120 and the first doping structure, as the difference between the second doping structure 120 and the first doping structure
  • the breakdown protection layer of course, the third doping structure 121 may be located at the part of the sidewall of the second doping structure 120 not covered by the first doping structure, and between the second doping structure 120 and the first doping structure at the same time , that is, the third doping structure 121 may cover the entire sidewall of the second doping structure 120 and the horizontal surface of the second doping structure 120 close to the first doping material layer 110 .
  • the third doping structure 121 may be located on the sidewall of the second doping structure 120, or may be located on the sidewall of the second doping structure 120 and between the second doping structure 120 and the first doping structure, At this time, the presence of the third doping structure 121 will not affect the position of the avalanche region and the avalanche probability between the second doping structure 120 and the first doping structure.
  • a microlens layer may also be formed, the microlens layer may be located on a surface away from the substrate, and the microlens layer may be used to focus the optical signal, so that the optical signal is concentrated in the area where the avalanche effect is likely to occur. Location. Specifically, the focal position of the microlens layer overlaps with the projection of the second doping structure on the horizontal plane, so that the light beam can be focused to the position opposite to the second doping structure, thereby improving the carrier collection efficiency.
  • the microlens layer may include microlenses arranged in an array, and the microlenses may be convex lenses and/or Fresnel lenses.
  • the formation method of the microlens layer may be reflow, etching back, or the like.
  • the reflow method can be specifically as follows: spin-coating a photosensitive organic material on the surface of the device away from the substrate, and then through exposure, development and heating to reflow, a microlens layer of the photosensitive organic material can be obtained;
  • the etching back can be specifically as follows: A flat layer is deposited on the surface of the device away from the substrate, and a photosensitive organic material is spin-coated on the flat layer, and then a mask layer of the photosensitive organic material is obtained by exposure and development and heating and reflow. The pattern on the organic material is transferred to the flat layer.
  • an inverted pyramid structure can also be formed, and the inverted pyramid structure can be an array of inverted pyramid structures, and the inverted pyramid structure is located on the side away from the substrate, and is used for refraction when light passes through, thereby changing the transmission direction of light , so that the light is not only transmitted in the vertical direction in the first doping material layer, thus increasing the light transmission path and increasing the possibility that the first doping material layer absorbs light to generate carriers.
  • the inverted pyramid structure can be located between the microlens layer and the film layer below it, so that light is focused and refracted. Therefore, the inverted pyramid structure can be formed before forming the microlens layer.
  • Embodiments of the present application provide a method for manufacturing a single-photon avalanche diode.
  • a second doping structure, a first doping structure, and a third doping structure may be sequentially formed on the substrate from bottom to top, or the lower right
  • a third doping structure, a first doping structure and a second doping structure are sequentially formed thereon, wherein the cross section of the second doping structure is smaller than the first doping material layer; the first doping material
  • the doping type of the layer and the second doping structure are consistent, and the doping concentration of the second doping structure is higher than that of the first doping material layer;
  • the first doping structure is located in the second doping structure between the doping structure and the first doping material layer, and covering the sidewall of the second doping structure;
  • the doping type of the first doping structure is opposite to that of the second doping structure, which The adjacent regions are used to form an avalanche region; the surface of the first dopant material layer is formed with
  • the first doping structure is formed on one side of the horizontal surface and the sidewall of the second doping structure, and the region adjacent to the first doping structure and the second doping structure is used for forming Avalanche region, and the high field region of the corner region adjacent to the second doping structure and the first doping structure is more likely to form an avalanche region, that is, the avalanche effect occurs in the edge region of the second doping structure and the first doping structure.
  • the cover material can provide an electric field that makes the multiple carriers in the first doped material layer move from the edge to the center, which is beneficial to the photogenerated carriers in the first doped material layer to the avalanche region. Therefore, the charge collection efficiency is improved to a certain extent, so the device has a high quantum efficiency, which can have a high photodetection efficiency.

Landscapes

  • Light Receiving Elements (AREA)

Abstract

La présente invention concerne une diode à avalanche à photon unique et son procédé de fabrication, un dispositif de détection de photons et un système. Une première structure dopée est formée sur une surface horizontale et une paroi latérale d'un côté d'une seconde structure dopée ; des zones adjacentes de la première structure dopée et de la seconde structure dopée sont utilisées pour former une zone d'avalanche ; et des zones de champ élevé de zones cornières adjacentes de la seconde structure dopée et de la première structure dopée sont plus susceptibles de former une zone d'avalanche, c'est-à-dire qu'un effet d'avalanche se produit au niveau des zones de bord de la seconde structure dopée et de la première structure dopée, et par conséquent, la probabilité de génération d'un effet d'avalanche est relativement élevée. De plus, un matériau de revêtement peut fournir un champ électrique qui amène des photons dans une première couche de matériau dopé à se déplacer d'un bord au centre, ce qui facilite le déplacement de porteurs de charge photo-générés dans la première couche de matériau dopé vers une zone d'avalanche, et améliore ainsi l'efficacité de collecte de charge dans une certaine mesure, de telle sorte que le dispositif a un rendement quantique relativement élevé, et peut ainsi offrir une efficacité de détection de photons relativement élevée.
PCT/CN2020/102783 2020-07-17 2020-07-17 Diode à avalanche à photon unique et son procédé de fabrication, dispositif de détection de photons et système Ceased WO2022011701A1 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
PCT/CN2020/102783 WO2022011701A1 (fr) 2020-07-17 2020-07-17 Diode à avalanche à photon unique et son procédé de fabrication, dispositif de détection de photons et système
CN202080099985.1A CN115428152B (zh) 2020-07-17 2020-07-17 一种单光子雪崩二极管及其制造方法、光检测器件及系统
CN202512049619.2A CN122028525A (zh) 2020-07-17 2020-07-17 一种单光子雪崩二极管及其制造方法、光检测器件及系统

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/CN2020/102783 WO2022011701A1 (fr) 2020-07-17 2020-07-17 Diode à avalanche à photon unique et son procédé de fabrication, dispositif de détection de photons et système

Publications (1)

Publication Number Publication Date
WO2022011701A1 true WO2022011701A1 (fr) 2022-01-20

Family

ID=79556079

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2020/102783 Ceased WO2022011701A1 (fr) 2020-07-17 2020-07-17 Diode à avalanche à photon unique et son procédé de fabrication, dispositif de détection de photons et système

Country Status (2)

Country Link
CN (2) CN122028525A (fr)
WO (1) WO2022011701A1 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20220373688A1 (en) * 2021-05-19 2022-11-24 nEYE Systems, Inc. Lidar with microlens array and integrated photonic switch array
US11754683B2 (en) 2021-05-10 2023-09-12 nEYE Systems, Inc. Pseudo monostatic LiDAR with two-dimensional silicon photonic mems switch array
CN116884981A (zh) * 2023-06-07 2023-10-13 边际科技(珠海)有限公司 一种响应0.85微米雪崩二极管与平面透镜的集成结构及其制程

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7105798B2 (en) * 2002-09-20 2006-09-12 Fujitsu Quantum Devices Limited Semiconductor light-receiving device with multiple potentials applied to layers of multiple conductivities
CN106298816A (zh) * 2016-10-11 2017-01-04 天津大学 集成淬灭电阻的单光子雪崩二极管及其制造方法
CN107946389A (zh) * 2017-11-14 2018-04-20 重庆邮电大学 一种针对长波段微弱光的cmos单光子雪崩二极管
CN108550592A (zh) * 2018-04-02 2018-09-18 重庆邮电大学 一种低暗计数率cmos spad光电器件

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9209320B1 (en) * 2014-08-07 2015-12-08 Omnivision Technologies, Inc. Method of fabricating a single photon avalanche diode imaging sensor
CN106449770B (zh) * 2016-12-07 2019-09-24 天津大学 防止边缘击穿的环形栅单光子雪崩二极管及其制备方法
US10193009B1 (en) * 2018-04-05 2019-01-29 Stmicroelectronics (Crolles 2) Sas Single photon avalanche gate sensor device

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7105798B2 (en) * 2002-09-20 2006-09-12 Fujitsu Quantum Devices Limited Semiconductor light-receiving device with multiple potentials applied to layers of multiple conductivities
CN106298816A (zh) * 2016-10-11 2017-01-04 天津大学 集成淬灭电阻的单光子雪崩二极管及其制造方法
CN107946389A (zh) * 2017-11-14 2018-04-20 重庆邮电大学 一种针对长波段微弱光的cmos单光子雪崩二极管
CN108550592A (zh) * 2018-04-02 2018-09-18 重庆邮电大学 一种低暗计数率cmos spad光电器件

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11754683B2 (en) 2021-05-10 2023-09-12 nEYE Systems, Inc. Pseudo monostatic LiDAR with two-dimensional silicon photonic mems switch array
US12461209B2 (en) 2021-05-10 2025-11-04 nEYE Systems, Inc. Pseudo monostatic LiDAR with two-dimensional silicon photonic MEMS switch array
US20220373688A1 (en) * 2021-05-19 2022-11-24 nEYE Systems, Inc. Lidar with microlens array and integrated photonic switch array
US12140676B2 (en) * 2021-05-19 2024-11-12 nEYE Systems, Inc. LiDAR with microlens array and integrated photonic switch array
CN116884981A (zh) * 2023-06-07 2023-10-13 边际科技(珠海)有限公司 一种响应0.85微米雪崩二极管与平面透镜的集成结构及其制程
CN116884981B (zh) * 2023-06-07 2024-04-23 边际科技(珠海)有限公司 一种响应0.85微米雪崩二极管与平面透镜的集成结构及其制程

Also Published As

Publication number Publication date
CN115428152B (zh) 2026-01-20
CN122028525A (zh) 2026-05-12
CN115428152A (zh) 2022-12-02

Similar Documents

Publication Publication Date Title
US9257589B2 (en) Single photon avalanche diode with second semiconductor layer burried in epitaxial layer
JP2020155783A (ja) 積層背面照射型ｓｐａｄアレイ
EP3544064B1 (fr) Photodétecteur et détection et télémétrie de la lumière
CN115443545B (zh) 一种单光子雪崩二极管及其制造方法、光检测器件及系统
US12283639B2 (en) Single-photon detection pixel and single-photon detection pixel array including the same
CN115428152B (zh) 一种单光子雪崩二极管及其制造方法、光检测器件及系统
TWM624210U (zh) 單光子崩潰二極體
KR20220114879A (ko) 이미지 센싱 장치
CN117936621B (zh) 光电转换器件及其制备方法、光电检测装置、电子设备
KR20250003375A (ko) 단광자 검출기
KR20240048506A (ko) 단일 광자 검출 소자, 전자 장치, 및 라이다 장치
US11335825B2 (en) Single-photon avalanche diode and a sensor array
US20250275272A1 (en) Single-photon detection device, single-photon detector, and single-photon detector array
US20240319340A1 (en) Single photon detection device, single photon detector, and electronic device
KR20250005020A (ko) 단일 광자 검출 소자, 전자 장치, 및 라이다 장치
CN110888139B (zh) 用于光敏装置的非连续布局
US20260033022A1 (en) Single photon detection device and electronic device comprising diffraction pattern
KR20230032808A (ko) 단일 광자 검출 소자, 단일 광자 검출기, 및 단일 광자 검출기 어레이
KR101762431B1 (ko) 크로스톡 방지 구조를 가지는 실리콘 광전자 증배센서
US20250040263A1 (en) SINGLE PHOTON AVALANCHE DIODE, ELECTRONIC DEVICE, AND LiDAR DEVICE
US20250040264A1 (en) Photodetection element, photodetector, and electronic device
EP4719002A2 (fr) Unité de diode à avalanche à photon unique et dispositif électronique
KR101762430B1 (ko) 이면 조사형 실리콘 광전자 증배센서 및 그 제조방법
JP2022083194A (ja) センサデバイス

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: 20944888

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 20944888

Country of ref document: EP

Kind code of ref document: A1