CN114442115A - Image sensor - Google Patents
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- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
- G01S17/00—Systems using the reflection or reradiation of electromagnetic waves other than radio waves, e.g. lidar systems
- G01S17/88—Lidar systems specially adapted for specific applications
- G01S17/89—Lidar systems specially adapted for specific applications for mapping or imaging
- G01S17/894—3D imaging with simultaneous measurement of time-of-flight at a 2D array of receiver pixels, e.g. time-of-flight cameras or flash lidar
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- G—PHYSICS
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- G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
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- G01S17/02—Systems using the reflection of electromagnetic waves other than radio waves
- G01S17/06—Systems determining position data of a target
- G01S17/08—Systems determining position data of a target for measuring distance only
- G01S17/32—Systems determining position data of a target for measuring distance only using transmission of continuous waves, whether amplitude-, frequency-, or phase-modulated, or unmodulated
- G01S17/36—Systems determining position data of a target for measuring distance only using transmission of continuous waves, whether amplitude-, frequency-, or phase-modulated, or unmodulated with phase comparison between the received signal and the contemporaneously transmitted signal
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- H01L27/144—Devices controlled by radiation
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- H01L27/144—Devices controlled by radiation
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- H01L27/14601—Structural or functional details thereof
- H01L27/14609—Pixel-elements with integrated switching, control, storage or amplification elements
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Abstract
The invention discloses an image sensor, which is characterized by comprising: a photodiode unit for receiving an optical signal reflected back by a detection target; the diode unit is electrically communicated with at least two different storage units in part of time period through at least two groups of transmission gates, and photo-generated charges converted from the return light information are transferred to the at least two different storage units, wherein at least one group of transmission gates in the at least two groups of transmission gates comprises at least two transmission gate units; the potential adjusting area is used for accelerating the transfer of the charges to the storage unit, and the potential adjusting area achieves the improvement of the transfer efficiency of the photo-generated charges from the photodiode to the floating diffusion node, so that the possibility of generating contradiction points at high speed and high quality of the sensor is reduced at the most basic level.
Description
Technical Field
The present disclosure relates to image sensors, and particularly to a three-dimensional image sensor.
Background
In recent years, with the development of image sensors, higher requirements are put on the aspects of miniaturization photoelectric conversion efficiency of the image sensor, rapid transfer of charges generated by conversion and the like, in traditional 2D imaging, on one hand, in order to ensure the rapid response of the sensor, the time for internal charge transfer and the like needs to be compressed as much as possible, and on the other hand, in the existing image sensor design framework, the charge transfer needs a certain time, otherwise, the photo-generated charge transfer is incomplete, and the problem of image retention and the like is caused in image acquisition.
With the technical development of laser radars, Time of Flight (TOF) has been receiving increasing attention, and the TOF principle is to obtain a target distance by continuously transmitting light pulses to a target and then receiving light returning from the object with a sensor and detecting the Time of Flight (round trip) of the light pulses.
Direct Time of Flight (DTOF) and Indirect Time of Flight (ITOF) are used as detection methods developed based on TOF, and the two detection methods have advantages in use and are receiving more and more attention.
The indirect time-of-flight detection mainly comprises the steps of acquiring a phase difference relation between a transmitted wave and a reflected echo of an object to be detected, acquiring distance information of the object to be detected by utilizing the phase difference relation, using the method in three-dimensional image acquisition with depth, needing longer integration time for acquiring farther detection distance, generating more photo-generated charges, generating more transferred charges, transmitting return light signals with different phase information to two different floating diffusion nodes (actually a storage unit) by generally adopting two complementary-phase signal control sensor transmission grids in the depth information acquisition, wherein once the charge transfer speed is lower, the time-of-flight distance information acquired by a detector array is inaccurate, the distance acquisition is inaccurate and the use is influenced, and if the two complementary-phase signal control transmission grids cannot rapidly and accurately shift the phase of the corresponding return light signals in the process, the information of the lowest layer of the ITOF detection is different, which has a great influence on the whole detection result.
Therefore, developing a memory cell capable of rapidly transferring photo-generated charges generated in the detector by the returning optical signal to the output is a challenge in two-dimensional and three-dimensional image sensor design.
Disclosure of Invention
The present application is directed to provide an image sensor to improve the fast transfer of photo-generated charges generated by an echo in the conventional image sensor.
In order to achieve the above purpose, the technical solutions adopted in the embodiments of the present application are as follows:
an embodiment of the present application provides an image sensor, including: a photodiode unit for receiving an optical signal reflected back by a detection target; the diode unit is electrically communicated with at least two different storage units in part of time period through at least two groups of transmission gates, and photo-generated charges converted from the return light information are transferred to the at least two different storage units, at least one group of transmission gates in the at least two groups of transmission gates comprises at least two transmission gates
A gate transfer unit;
a potential adjustment region to accelerate transfer of the charge to the memory cell.
Optionally, the at least two groups of transfer gates are two groups of transfer gates, and the at least two different storage units are two storage units.
Optionally, the gates of at least two transfer gate cells within the same transfer group are connected together and receive the same control signal.
Optionally, the memory cell is doped with a first type, and the image sensor further comprises an epitaxial layer doped with a second type opposite to the doping of the memory cell.
Optionally, the memory cell is doped with a first type, and the image sensor further includes an epitaxial layer doped with the same first type as the memory cell.
Optionally, the number of at least two transfer gate units in the same transfer group is an even number.
Optionally, the potential adjustment region is a second-type doped region.
Optionally, the potential tuning region is located within the epitaxial layer.
Optionally, the potential adjusting region is located between the image sensor and the first surface of the epitaxial layer opposite to the epitaxial layer.
Optionally, the potential adjusting region penetrates through a first surface of the image sensor opposite to the epitaxial layer to a second surface of the image sensor.
The beneficial effect of this application is:
the image sensor provided by the embodiment of the application can comprise a photodiode unit, wherein the photodiode unit is used for receiving an optical signal reflected by a detected target;
the diode unit is electrically communicated with at least two different storage units in part of time period through at least two groups of transmission gates, and photo-generated charges converted from the return light information are transferred to the at least two different storage units, wherein at least one group of transmission gates in the at least two groups of transmission gates comprises
Comprises at least two transmission gate units;
the potential adjusting area is used for accelerating the transfer of the charges to the storage units, so that the photo-generated charges generated by the receiving photodiode of the return light signal can be transferred to a corresponding storage unit (or a floating diffusion node) through the transmission gate group, namely the transmission group is equivalent to a plurality of transfer channels arranged between the photodiode and the storage unit, and the potential difference is adjusted through the potential adjusting area, so that the rapid change of the potential characteristics in the diode can be rapidly realized, and the effect of rapidly transferring the photo-generated charges is achieved.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained from the drawings without inventive effort.
Fig. 1 is a schematic diagram of a prior art image sensor detection unit according to an embodiment of the present application;
FIG. 2 is a schematic diagram of a sensor circuit capable of obtaining depth information according to an embodiment of the present disclosure;
FIG. 3 is a schematic diagram of another sensor circuit capable of obtaining depth information according to an embodiment of the present disclosure;
fig. 4 is a schematic diagram of a sensor unit capable of obtaining depth information according to an embodiment of the present disclosure;
FIG. 5 is a cross-sectional view of a sensor unit capable of obtaining depth information according to an embodiment of the present disclosure;
FIG. 6 is a schematic diagram of another sensor unit capable of obtaining depth information according to an embodiment of the present disclosure;
FIG. 7 is a diagram illustrating an effect of a sensor unit capable of obtaining depth information according to an embodiment of the present disclosure;
FIG. 8 is a diagram comparing the effect of the sensor unit provided in the embodiment of the present application with that of the conventional sensor;
FIG. 9 is a schematic diagram of another sensor unit capable of obtaining depth information according to an embodiment of the present disclosure;
FIG. 10 is a schematic diagram of another sensor unit capable of obtaining depth information according to an embodiment of the present disclosure;
FIG. 11 is a schematic diagram of an assisted transfer doping region disposed in a sensor cell according to an embodiment of the present disclosure;
FIG. 12 is a schematic view of an auxiliary transfer doping region disposed in another sensor cell according to an embodiment of the present application;
FIG. 13 is a schematic view of an assisted transfer doping region disposed in another sensor cell according to an embodiment of the present application;
fig. 14 is a schematic diagram illustrating an effect of a cross-sectional potential distribution under the structure of the assisted transfer doping region of fig. 11 according to an embodiment of the present application.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. The components of the embodiments of the present application, generally described and illustrated in the figures herein, can be arranged and designed in a wide variety of different configurations.
Thus, the following detailed description of the embodiments of the present application, as presented in the figures, is not intended to limit the scope of the claimed application, but is merely representative of selected embodiments of the application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.
It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined and explained in subsequent figures.
Fig. 1 is a schematic diagram of a prior art image sensor detection unit according to an embodiment of the present application. As shown in fig. 1, a 4T structure is generally adopted by the existing image sensor, where 101 is a photodiode unit, that is, a return light signal can be converted into photo-generated charges (including electrons, holes, etc., and a photo-generated electron is not limited herein for efficient transmission of the general photo-generated charges, 102 is a transistor type and is not limited herein, a control signal is applied to a gate of 102, photo-generated charges generated in the diode can be transferred to a floating diffusion node 103, and the photo-generated charges in the floating diffusion node can be transferred to a readout circuit after a voltage is applied to a gate of the readout transistor 105, and corresponding information is output by subsequent circuit processing, where 104 is a reset transistor for performing reset on the sensor unit, 106 is a row selection transistor for transferring row selection information, when a certain row is selected, the gate of the row selection transistor can be controlled by a high-level control signal, and it can be known from the above description that the transfer gate 102 is crucial for the transfer of the generated charges of the image sensor unit, and in fig. 1, the transfer gate is only arranged at one corner of the photodiode, and there are also designs arranged at different sides or corners in the layout in the industry, but actually, this arrangement can obviously show that the range of action of the transfer gate is limited, and the charges generated by the echo will affect the high-quality and high-efficiency operation of the detector more and more on the premise that the current requirements for the information acquisition and processing speed of the detector are faster and faster due to the small change of the potential at the farther position, so an image sensor capable of improving the transfer efficiency is needed to meet the requirements for the performance of the image sensor under the increasing development, fig. 1 is a schematic diagram of a conventional two-dimensional image sensor, and certainly, in a conventional depth information acquisition pixel structure, a complementary phase control module is added to the structure of fig. 1, and only one transfer gate is in operation at a certain time in actual operation, so that a problem that photo-generated charges cannot be quickly and completely transferred is caused, which causes that information of the most basic layer of detection may be deviated, and thus, the requirement of high-speed and accurate acquisition of three-dimensional information cannot be met.
In order to solve the problems in the prior art, the invention changes the transmission gates into transmission gate groups in the pixel unit design, fig. 2 is a schematic circuit diagram of a sensor capable of obtaining depth information provided by an embodiment of the present application, and as can be seen from the implemented circuit diagram, the invention changes the transmission gates into transmission gate groups, which include at least two transmission gate units, and the control signals of the two transmission gate units are completely the same, for example, the two transmission gate groups in fig. 2 are TX1 and TX2, respectively, and for efficient depth information measurement using ITOF, it is necessary to design two transmission gate groups, where TX1 and TX2 receive two control signals with complementary phases, for example, the control signal of TX1 is a 0 ° or 90 ° received phase difference signal, the control signal of TX2 is a 180 ° and 270 ° phase difference signal, and thus the signal channels of the two transmission gates are just complementary, the effect of efficient detection is achieved, in order to ensure that each phase information can be transferred to the corresponding storage unit (the first floating diffusion node FD1 and the second floating diffusion node FD2) efficiently and quickly, the first transmission gate group TX1 receives 0 ° or 90 ° receiving phase difference signal control, the second transmission gate group TX2 receives 180 ° or 270 ° receiving phase difference signal control, and the gates of each transmission gate unit in the same transmission gate group are connected together, so that the transmission channel between the photodiode and the floating diffusion node is changed into two parallel groups, on one hand, the number of transfer channels can be increased, on the other hand, the potential distribution characteristic in the photodiode can be changed to a larger extent, thereby accelerating the speed of electron transfer, of course, the sensor unit for acquiring 3-dimensional depth information is taken as an example here, and actually, the two-dimensional image sensor can also be used, therefore, the problems of image retention and the like of the acquired image are reduced, and the functions of other parts are the same as those of the prior art and are not repeated.
Fig. 3 is a schematic diagram of another sensor circuit capable of obtaining depth information according to an embodiment of the present disclosure, and is different from fig. 2 in that the number of transfer gate units in each transfer gate group in fig. 3 is 4, which further increases the number of transfer channels from the photodiode to the floating diffusion node, and also further increases the range within which the potential in the photodiode is affected, although the number of transfer gates implemented in detail is not limited here, and may also be 3, 5, 6, and so on.
FIG. 4 is a schematic diagram of a sensor unit capable of obtaining depth information according to an embodiment of the present disclosure; as can be easily seen from the figure, in order to realize the implementation scheme described in fig. 2 that includes two transfer gate units in the transfer gate group, sub-transfer gate units of the transfer gate are disposed on opposite sides of the photo-electric element, such as two TX1 transfer gate units oppositely disposed and two TX2 transfer gate units oppositely disposed in fig. 4, and are disposed such that two transfer directions of the same transfer gate group are located in different directions, similar to a seesaw structure, so that the probability of photo-generated charges being rapidly transferred away is greater, and in addition, in order to ensure that intermediate electrons can be rapidly transferred to both sides, doping in the middle of the photodiode is different from that of a floating diffusion node, such as doping in the floating diffusion node is doping in a silicon matrix for a group V element in a chemical periodic table, and doping can be performed here with an element N, P, As or the like, so that a group III element is doped in the middle region of the photodiode, for example, doping is carried out by using B, Al, Ga, In and the like, a middle region with raised potential is obtained, which is equivalent to arranging a repelling region of electrons In the middle, and In cooperation with the oppositely arranged transmission gate units, which is equivalent to constructing two electron ramps when being conducted, photo-generated charges are rapidly transferred to two directions, so that the transfer efficiency of the electrons is greatly improved.
FIG. 5 is a cross-sectional view of a sensor unit capable of obtaining depth information according to an embodiment of the present disclosure; the structure is a cross-sectional structure along the position of figure 4, wherein the epitaxial layer is a P-type epitaxial layer doped with group III elements, the P-type epitaxial layer is doped with group V elements to form a PDN photoelectric conversion region, the surface of the P-type epitaxial layer is covered with a P-type doped region with doping concentration larger than that of the epitaxial layer to form a surface clamp, the P-type doped region with doping concentration larger than that of the epitaxial layer and smaller than that of the surface clamp is further doped in the middle of the photoelectric region of the PDN to form a doped region for assisting the rapid electron transfer, the depth of the doped region optimally penetrates through the PDN region, so that the effect of the rapid electron transfer can be ensured, meanwhile, the proportion of the doped region occupying the total PDN area is optimally set to be 5% -15%, so that the photoelectric conversion efficiency of the device can be ensured not influenced, the doping depth is not limited to penetrate through and can be set to be more than half of the N-type doping depth in the PDN, and the structure is not limited to be realized by adopting the structure, in order to ensure the charge transfer direction and the opposite side arrangement characteristic of the transfer gates, the connecting line of at least two transfer gate units arranged on the symmetrical sides is parallel to the central line of one of the photodiode units, so that the formed potential elevation can be ensured to have correct directivity for the charge transfer acceleration, and the effect of accurate and efficient charge transfer is ensured.
FIG. 6 is a schematic diagram of another sensor unit capable of obtaining depth information according to an embodiment of the present disclosure; different from fig. 5, the epitaxial doping is a doping of N-type material of group V, so that the photoelectric conversion efficiency can be increased, that is, more photo-generated charges can be generated, the design advantages of the present invention can be embodied more greatly by matching with the structure of the present invention, and more photo-generated charges can also be made into effective photo-generated charges, thereby improving the detection efficiency and detection quality of the image sensor unit.
FIG. 7 is an effect diagram of a sensor unit capable of obtaining depth information according to an embodiment of the present disclosure; it can be seen from the figure that a more balanced transfer electric field can be formed as much as possible by the design of the present invention, and therefore photo-generated charges generated by the photoelectric conversion region can be rapidly transferred to two transfer gate units disposed at opposite sides.
To further illustrate the technical effects of the present invention, fig. 8 is a quantitative comparison, compared with the conventional single transfer gate scheme, the scheme of the present invention can rapidly transfer electrons, in fig. 8, a curve I is a curve of the amount of residual charge in the charge accumulation region of the transfer gate diode with respect to time, a curve II is a curve of the amount of residual charge in the charge accumulation region of the transfer gate group diode with respect to time, actual experimental parameters are not given, and an actual measurement result is, for example, that the amount of residual charge in the present invention is only about 5% in 1ns, while the amount of residual charge in the prior art is about 40% in the same time.
FIG. 9 is a schematic diagram of another sensor unit capable of obtaining depth information according to an embodiment of the present disclosure; it is illustrated corresponding to the embodiment of fig. 3 where each transfer gate group includes four transfer gate units, the transfer speed of photo-generated charge can be further increased by further increasing the number of transfer units in the transfer gate group, as shown in fig. 9 where the transfer gates are arranged in the photoelectric conversion region, each of the same transfer gate units are arranged in a staggered manner, and the pitches of each unit are substantially the same, so as to form a uniform arrangement effect, and in cooperation with the doping region for assisting the rapid transfer of electrons, a lift-up effect similar to 2 units is achieved, in order to ensure that the electron transfer accuracy is achieved, the center line of the doping region is not parallel to the center line of the photoelectric conversion region, in order to ensure the balance of electron transfer in each direction, and to adapt to the existing shape of the photoelectric conversion region, and optimally setting the number of transfer gate units of each transfer gate group to be an even number, so as to ensure that the photo-generated charge is transferred more efficiently without changing the existing shape of the photoelectric conversion region, other parts similar to those of fig. 4 and 5 are not described in detail.
Fig. 10 and fig. 9 have the same basic functions, except that the epitaxial layer of fig. 10 is an N-type epitaxial layer, which can generate higher photo-generated charge conversion efficiency, and similar to fig. 6, the structure of the present invention will have more optimized adaptive effect on the N-type epitaxial layer structure, and will not be described in detail herein.
For further explanation in conjunction with the cross-sectional structure of fig. 10, fig. 11-13 are schematic diagrams of assisted transfer doping regions disposed in different sensor cells according to embodiments of the present application; wherein the substrate layer is doped with N-type material to form an N-type epitaxial substrate, the PDN conversion region with the same function as the P-type doping is positioned at the upper part of the substrate layer, p-well regions with P-type doping are arranged at the periphery of the substrate and the PDN, so as to assist photo-generated charges to be quickly transferred to corresponding floating diffusion nodes through a plurality of transmission gate units on the premise of arrangement of the transmission gate group structure, the transfer-assist doping region can be provided according to three different structures of figures 11-13, with a doping concentration less than the surface-clamped P-type doping concentration, but greater than the P-type material doping concentration in the P-well, the fig. 11 structure essentially places the transfer-assist doping region in the N-type epitaxy, and a depth greater than 1/2 of the depth of the N-type epitaxial layer, thus raising the intermediate potential, meanwhile, the area of a main photoelectric conversion region is not occupied, and two important parameters of photo-generated charge efficiency and photoelectric transfer efficiency are further ensured. Fig. 12 uses a scheme of disposing a transfer-assist doping region in the transition region PDN, which is similar to the previous arrangement of the transfer-assist doping region in fig. 5 for a P-type substrate and will not be described again here. Fig. 13 is a scheme of an assisted transfer doping region disposed through the epitaxy and the conversion region PDN, and compared with fig. 11 and 12, the structure can improve the charge transfer efficiency to a greater extent, and the cross-sectional area can be set smaller than that in fig. 12, so that both the photoelectric conversion efficiency and the charge transfer rate can be improved, which is not limited herein.
Further, in order to ensure the photoelectric transfer efficiency, the N-type epitaxial layers in fig. 10-13 and fig. 6 are further connected with an auxiliary depletion layer, and the auxiliary depletion layer is made of Al2O3、HaO2The auxiliary depletion layer can assist the photodiode with the N-type epitaxy to form a fully depleted device, and can also raise the potential of the adjacent side of the epitaxial layer in the invention, for example, the potential measurement is performed from the position shown in fig. 11, and the result is shown in fig. 14, where the depth from the surface of the abscissa is the depth from the upper surface of fig. 11, that is, after the auxiliary depletion layer is arranged, the potential of the part connected with the auxiliary depletion layer is raised, and the effect is similar to that of the auxiliary depletion layerIn the assisted transfer doping region doped with P-type residue, the photo-generated charges generated in this way are rapidly transferred in the longitudinal direction, and will not be described in detail herein.
It is to be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application. It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined or explained in subsequent figures. The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.
Claims (10)
1. An image sensor, comprising:
a photodiode unit for receiving an optical signal reflected back by a detection target; the diode unit is electrically communicated with at least two different storage units in part of time period through at least two groups of transmission gates, and photo-generated charges converted from the return light information are transferred to the at least two different storage units, wherein at least one group of transmission gates in the at least two groups of transmission gates comprises at least two transmission gate units;
a potential adjustment region to accelerate transfer of the charge to the memory cell.
2. The image sensor of claim 1, wherein the at least two sets of transfer gates are two sets of transfer gates, and the at least two different memory cells are two memory cells.
3. The image sensor of claim 1, wherein gates of at least two transfer gate cells within the same transfer group are connected together and receive the same control signal.
4. The image sensor of claim 1, wherein the memory cell is doped a first type, and the image sensor further comprises an epitaxial layer doped a second type opposite the memory cell doping.
5. The image sensor of claim 1, wherein the memory cell is doped a first type, and the image sensor further comprises an epitaxial layer doped the same first type as the memory cell.
6. The image sensor of claim 1, wherein the number of at least two transfer gate cells within the same transfer group is an even number.
7. The image sensor of claim 1, wherein the potential adjustment region is a second-type doped region.
8. The image sensor of claim 1, wherein the potential adjustment region is located within an epitaxial layer.
9. The image sensor of claim 1, wherein the potential adjustment region is located between the image sensor and a first surface of the epitaxial layer opposite the epitaxial layer to the epitaxial layer.
10. The image sensor of claim 1, wherein the potential adjustment region extends through a first surface of the image sensor opposite the epitaxial layer to a second surface of the image sensor.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202011187564.2A CN114442115A (en) | 2020-10-30 | 2020-10-30 | Image sensor |
| US18/033,388 US20230411417A1 (en) | 2020-10-30 | 2021-09-15 | Image sensor |
| PCT/CN2021/118376 WO2022089069A1 (en) | 2020-10-30 | 2021-09-15 | Image sensor |
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| CN202011187564.2A CN114442115A (en) | 2020-10-30 | 2020-10-30 | Image sensor |
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