WO2022206223A1

WO2022206223A1 - Barrier-adjustment-type distance information acquisition sensor, detection system using same, and electronic device

Info

Publication number: WO2022206223A1
Application number: PCT/CN2022/077632
Authority: WO
Inventors: 雷述宇
Original assignee: 宁波飞芯电子科技有限公司
Priority date: 2021-03-30
Filing date: 2022-02-24
Publication date: 2022-10-06
Also published as: CN113093151A

Abstract

Provided is a barrier-adjustment-type distance information acquisition sensor, comprising: a semiconductor substrate, which comprises a conversion region for converting an optical signal into a photo-generated charge; and a first-type doped region, which is disposed in a nearby area of one surface of the semiconductor substrate. The doping type of the conversion region is different from that of the first-type doped region. The first-type doped region extends to a partial area of one surface of the semiconductor substrate, and is connected to a gate of a control portion. The conversion region comprises a barrier adjustment region. The barrier adjustment region comes into contact with a P-well area surrounding a floating diffusion node, or is spaced apart from the P-well area by a preset gap.

Description

A potential barrier adjustment type distance information acquisition sensor and detection system and electronic equipment using the same

CROSS-REFERENCE TO RELATED APPLICATIONS

This application requires the application number 202110338868.2 to be submitted to the China Patent Office on March 30, 2021, and the application name is "A distance information acquisition sensor of a potential barrier adjustment type and a detection system and electronic equipment using the same". Priority, the entire contents of which are incorporated herein by reference.

technical field

The present application relates to the technical field of lidar detection, in particular to a time-of-flight detection scheme, and more particularly to a potential barrier adjustment type distance information acquisition sensor, a detection system and electronic equipment using the same.

Background technique

With the development of lidar technology, Time of Flight (TOF) has received more and more attention. The principle of TOF ranging is to continuously send light pulses to the target, and then use the sensor to receive the target The light returned by the object is obtained by detecting the flight (round-trip) time of the light pulse to obtain the distance from the object.

Direct Time of Flight (DTOF) and Indirect Time of Flight (ITOF) are the detection methods based on the development of TOF. These two detection methods have their own advantages in the use process, and are subject to more and more more and more attention. Among them, ITOF is an integral type detection scheme, which can receive the detection light signal emitted by the light source and returned by the detected object through the field of view through different phase delays. The delay phase related to the flight time can be obtained by processing the different phase delay signals. , and then obtain the final distance information of the detected object.

In the currently used ITOF modulation and demodulation type detection scheme, the pixel unit design largely refers to the traditional 4T type CIS structure 2D image sensor. This design is suitable for the current TOF type detection scheme. There are certain limitations in the design of the pixel unit. For example, due to the high requirements of two-dimensional images for image quality, it is necessary to ensure that the photoelectric conversion area to the output integrating capacitor or the floating diffusion node has a higher potential, so as to ensure that the image display does not occur due to insufficient potential barrier. The problem of low imaging quality, however, such a high potential barrier is not needed in distance detection, so still using the previous pixel structure will result in a higher voltage for driving the channel constructed by charge transfer, so the energy consumption of the entire pixel array will be very high. On the other hand, for the pixel unit with higher potential barrier, only the transmission channel can be built at high voltage, the actual scope of action is limited, and in many cases, the electron transfer needs to take a longer path, which will lead to the transmission efficiency. If it is lower, the complementary delay phase is used in the ITOF detection to perform a more sufficient absorption conversion for the primary emission light, which also requires the pixel unit used in the distance detection system to optimally have a higher charge transfer speed.

Therefore, there is an urgent need for a new type that can optimize the design of the potential barrier of the existing pixel unit to reduce the potential barrier between the photoelectric conversion region of the existing pixel unit and the floating diffusion node, so as to ensure the use of complementary delay phases. The received sensor can transfer the charge at a higher speed and efficiency, while also reducing the energy consumption of the entire sensor.

SUMMARY OF THE INVENTION

In view of this, the present application provides a distance information acquisition sensor of a potential barrier adjustment type and a detection system and electronic device using the same, so as to solve the problems of existing pixel unit designs in distance detection application scenarios, charge transfer speed and efficiency. Lower energy consumption, higher energy consumption, more heat generation and more problems affecting detector performance and so on.

The technical solutions adopted in the embodiments of the present application are as follows:

In a first aspect, an embodiment of the present application provides a potential barrier adjustment type distance information acquisition sensor, including: a semiconductor substrate, including a conversion region for converting optical signals into photo-generated charges; and one of the semiconductor substrates a first-type doped region in a region near the surface, wherein the conversion region is of a different doping type than the first-type doped region, the first-type doped region extending to a portion of the surface of one of the semiconductor substrates The conversion region includes a barrier adjustment region, and the barrier adjustment region is in contact with the P-well region surrounding the floating diffusion node or has a predetermined gap.

In an embodiment, the number of the control parts is two or more, and the control parts are MOS type transistors.

In one embodiment, the control part is used to adjust the potential of the photo-generated charges generated in the conversion region to the floating diffusion node, so as to change the resistance of the photo-generated charges to movement.

In an embodiment, the voltage range applied to the gate of the control part is 1V-1.5V.

In one embodiment, the P-well region is further connected with an isolation portion defining the conversion region to form a pixel unit.

In one embodiment, the doping type of the conversion region is N-type doping, and the doping type of the first doping region is P-type doping.

In an embodiment, the first doping region is provided with a clamping region for clamping the photo-generated charges, and the P-type doping concentration in the clamping region is greater than that in the first doping region impurity concentration.

In one embodiment, the control voltage applied to the gate of the control part is lower than the control voltage of the communication channel constructed by the control part between the photoelectric conversion region and the floating diffusion node.

In one embodiment, the control part changes the potential barrier between the conversion region and the floating diffusion node by adjusting the control voltage of the gate, so as to change the potential barrier between the conversion region and the floating diffusion node between the conversion region and the floating diffusion node. A photo-generated charge transfer region that forms a barrier-affected region between them.

In one embodiment, a spacer is provided between the control part and the floating diffusion node.

In a second aspect, an embodiment of the present application provides a detection system, which is applied to the distance information acquisition sensor of the potential barrier adjustment type described in the first aspect to acquire distance information. The detection system includes: a light source for illuminating a bright field of view; and a receiving module including a potential barrier adjustment type distance information acquisition sensor including a semiconductor substrate and a first type disposed in a region near a surface of one of the semiconductor substrates a doped region, the semiconductor substrate includes a conversion region for converting the return light signal of the light source in the field of view into photo-generated charges, the conversion region is different from the doping type of the first type doped region, so The first type doped region extends to a partial region of a surface of the semiconductor body and is connected to the gate of the control portion, the conversion region includes a barrier adjustment region, the barrier adjustment region is connected to the P surrounding the floating diffusion node The well regions are in contact or spaced apart by a predetermined gap.

In a third aspect, an embodiment of the present application provides an electronic device including a distance information acquisition sensor of the potential barrier adjustment type of the first aspect of the present application.

The beneficial effects of this application are:

A potential barrier adjustment type distance information acquisition sensor provided by an embodiment of the present application includes: a semiconductor substrate, including a conversion region for converting optical signals into photo-generated charges; a first-type doped region, wherein the conversion region is of a different doping type from the first-type doped region, and the first-type doped region extends to a partial area of a surface of the semiconductor body and is connected to a control The gate of the portion, the conversion region includes a barrier adjustment region, and the barrier adjustment region is in contact with the P-well region surrounding the floating diffusion node or is spaced by a predetermined gap. In the present invention, a potential barrier adjustment region is set inside the pixel unit, and the potential barrier adjustment region is further in contact with the P well region surrounding the floating diffusion node or with a preset gap, so as to ensure the transformation region of the potential barrier adjustment region to the entire pixel unit. The potential barrier to the floating diffusion node is lowered, and the effect of the control part to rapidly transfer the photo-generated charges under low voltage is realized, so that the pixel unit is more suitable for the system of obtaining distance information.

Description of drawings

In order to illustrate the technical solutions of the embodiments of the present application more clearly, the following drawings will briefly introduce the drawings that need to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore do not It should be regarded as a limitation of the scope, and for those of ordinary skill in the art, other related drawings can also be obtained according to these drawings without any creative effort.

1 is a schematic diagram of an array-type receiving module according to an embodiment of the present application;

FIG. 2 is a schematic diagram of a control section constructing a channel according to an embodiment of the present application;

3 is a schematic diagram of a control unit constructing a channel in a pixel unit according to an embodiment of the present application in the prior art;

4 is a schematic diagram of a potential barrier adjustment region and a floating diffusion node having a preset interval according to an embodiment of the present application;

5 is a schematic diagram of connecting a potential barrier adjustment region and a floating diffusion node according to an embodiment of the present application;

6 is a schematic diagram of current flow in a pixel unit provided by an embodiment of the present application using the pixel structure of the present invention in a state where a voltage is applied by a control unit;

FIG. 7 is a schematic diagram comparing a pixel structure provided by an embodiment of the present application with a potential barrier provided by the prior art;

8 is a schematic diagram of the potential distribution of the pixel unit provided by the embodiment of the present application when different voltages are applied by the control unit;

FIG. 9 is a schematic diagram of potential values of a pixel unit provided by an embodiment of the present application when different voltages are applied by the control unit.

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments It is a part of the embodiments of the present application, but not all of the embodiments. The components of the embodiments of the present application generally described and illustrated in the drawings herein may be arranged and designed in a variety of different configurations.

Thus, the following detailed description of the embodiments of the application provided in the accompanying drawings is not intended to limit the scope of the application as claimed, but is merely representative of selected embodiments of the application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present application.

It should be noted that like numerals and letters refer to like items in the following figures, so once an item is defined in one figure, it does not require further definition and explanation in subsequent figures.

The detection system currently used basically includes: a light source module, a processing module, and a light receiving module. The light source module includes but is not limited to semiconductor lasers, solid-state lasers, and may also include other types of lasers. When using a semiconductor laser as a light source, a vertical cavity surface emitting laser VCSEL (Vertical-cavity surface-emitting laser) or an edge-emitting semiconductor laser EEL (edge-emitting laser) can be used, which is only illustrative and not specifically limited here. The light source module emits sine wave, square wave, triangle wave, or pulse wave, etc., most of which are lasers with a certain wavelength in ranging applications, such as 950nm infrared lasers (optimally near-infrared lasers). The emitted light is projected into the field of view, and the object to be detected in the field of view can reflect the projected laser light to form return light, which enters the detection system and is captured by the light receiving module. The light receiving module may include a photoelectric conversion portion, such as an array type sensor composed of CMOS, CCD, or the like. The light receiving module may also include multiple lenses to form more than one image plane, that is, the light receiving module includes more than one image plane. The photoelectric conversion part of the light receiving module is located at one of the image planes, which can receive the most commonly used four-phase scheme to obtain 0°, 90°, 180° and 270° delayed received signals. The four-phase distance calculation scheme is described here by taking the sine wave method as an example. The amplitude of the received signal is measured at four equally spaced points (such as 90° or 1/4λ interval). The following is the distance calculation of four-phase ranging formula:

The ratio of the difference between A1 and A3 to the difference between A2 and A4 is equal to the tangent of the phase angle. ArcTan is actually a bivariate arctangent function that maps to the appropriate quadrant, defined as 0° or 180° respectively when A2=A4 and A1>A3 or A3>A1.

The distance to the target is determined by the following formula:

At this point, it is necessary to determine the frequency of the emitted laser to measure the distance, where c is the speed of light,

is the phase angle (measured in radians) and f is the modulation frequency. The above scheme can achieve the effect of distance detection for the detected object in the field of view. This scheme is called the four-phase delay scheme to obtain the detection result. Of course, the photoelectric conversion of the receiving module generates different information, and in some cases also Use the 0° and 180° two-phase scheme to obtain the information of the detected object. There are also documents that disclose 0°, 120° and 240° three-phase acquisition of target information, and even some documents also disclose a five-phase difference delay scheme. This application It is not specifically limited. In actual measurement, a square wave is also used for detection, and its mechanism is similar to that of a sine wave, but the calculation formula is different, which will not be repeated here.

The light receiving module can be an array type receiving module as shown in Fig. 1, and the array type receiving module includes a pixel unit 110 composed of diodes. In actual implementation, M*N pixel units may be used to form the active area of the array-type receiving module, wherein the number of pixel units may be in the order of tens of thousands or even hundreds of thousands, which is not limited here. The array-type receiving module may include a lens portion 101 and a semiconductor base portion 102 . The lens part includes a plurality of lens units, and the lens units may be composed of microlens units having predetermined curvatures. In order to ensure maximum utilization of the returned light, the lens portion may also include a structure with more than one layer, and the specific implementation scheme is not limited here. In a more optimal case, the semiconductor base part 102 can be arranged at the position of the focal plane corresponding to the lens part 101, which can ensure that the detection unit can obtain accurate return light information to the greatest extent possible. In this case, the lens of the lens part 101 can be constructed An optical channel, so that the signal received by the photosensitive part of the detection unit is near the corresponding focal position. The semiconductor base part 102 includes photosensitive pixels arranged in an array type, and the photosensitive pixels can be formed by doping on the semiconductor base part 102 to form photosensitive units of the type such as CCD or CMOS. In addition, the semiconductor base portion 102 may also contain analog signal processing circuits, pixel level control circuits, analog-to-digital conversion circuits (ADCs), and the like used in pixel cell readout. For the positional relationship arrangement of these circuits and the photosensitive unit, a front-illumination process in which the circuit layer is arranged upstream of the photosensitive unit in the propagation direction of the returning light can be used, or a back-illumination process in which the circuit layer is arranged downstream of the photosensitive unit in the propagation direction of the returning light can be used. process, and the specific implementation is not limited here. The photosensitive unit and some of the above circuits can be disposed on different semiconductor layers, and then a stacking process can be used to achieve a higher integrated design, and the specific implementation scheme is not limited here.

In the prior art, when a positive voltage is applied to the diode (the P terminal is connected to the positive terminal and the N terminal is connected to the negative terminal), the diode is turned on, and a current flows through the PN junction thereof. This is because when the P-type semiconductor terminal is at a positive voltage, the negative electrons of the N-type semiconductor are attracted and flock to the P-type semiconductor terminal to which the positive voltage is applied, while the positrons in the P-type semiconductor move toward the N-type semiconductor terminal. , thereby forming a current. In the same way, when a reverse voltage is applied to the diode (P terminal is connected to the negative pole, and N terminal is connected to the positive pole), the voltage at the P-type semiconductor terminal is negative at this time, the positive electrons are gathered at the P-type semiconductor terminal, and the negative electrons are gathered at the N terminal. Type semiconductor terminal, electrons do not move, no current flows through its PN junction, and the diode is cut off. For field transistors, when there is no voltage at the gate, it can be seen from the previous analysis that there will be no current flowing between the source and drain, and the field effect transistor is in the cut-off state at this time, as shown in Figure 2, when there is a positive When the voltage is applied to the gate of the N-channel MOS FET, due to the action of the electric field, the negative electrons of the source and drain of the N-type semiconductor are attracted out to the gate, but due to the blocking of the oxide film, The electrons are gathered in the P-type semiconductor between the two N-channels as shown in Figure 2, thereby forming a current and making the source and drain conduct. We can also imagine that there is a trench between two N-type semiconductors, and the gate voltage is equivalent to building a bridge between them. The size of the bridge is determined by the gate voltage. Generally, in order to ensure the potential barrier of the PN junction To be reliably eliminated, the voltage applied to the gate needs to be guaranteed to be within the value range of 2.5V-2.8V.

FIG. 3 is a schematic structural diagram of a pixel unit in the prior art. In the prior art, a conversion area 301 is included in the pixel unit, and the return light signal reflected by the field of view in the conversion area is absorbed by the conversion area. Using the photoelectric conversion phenomenon, the returned light generates photo-generated charges in the conversion area. Since the traditional CIS structure design is adopted in the structure, in order to ensure the potential barrier between the conversion region and the floating diffusion region 303 (including two sets of floating diffusion nodes 3031 and 3032 ), the conversion region and the floating diffusion region 303 are far away to ensure Photogenerated charges do not leak. In order to ensure that the control part 302 (including the two sub-control units 3021 and 3022 ) can transmit the photo-generated charges generated in the photoelectric conversion region more accurately under the action of the complementary phase control signal, it is necessary to ensure that the gate of the control part applies sufficient Generally, a gate voltage between 2.5V-3.3V needs to be applied to form a photo-generated charge transfer channel, and the effect of receiving the photo-generated charges by two sets of complementary delayed phases is realized through the control of complementary signals. The floating diffusion node is generally arranged in the P-type doped region, which further increases the potential barrier between the conversion region and the floating diffusion node. However, in such an existing structure, since the control gate requires a higher voltage, the energy consumption of the entire pixel unit will be higher, and therefore the pixel unit will generate more heat. This type of pixel unit is used to form The array sensor will make the entire array chip consume more energy and generate more waste heat, which will place higher requirements on the heat dissipation design of the entire chip. In addition, although this pixel structure can ensure that no charge leakage occurs between the conversion region and the floating diffusion node, that is, the interference effect is small, but in fact, the effect on distance detection is relatively small. Due to the complementary phase scheme used in distance detection, it requires More is the need to transfer charges quickly, and although the existing technology is high voltage transmission, the actual principle is to apply a voltage to the P-type doped region under the gate to form an inversion layer at this part, thereby forming a channel connecting the conversion region. , the movement path of the photo-generated charges may be prolonged, resulting in insufficient photo-generated charge transfer in the control phase. On the other hand, photo-generated charges need to be transferred along a fixed channel, which also virtually restricts the transfer speed and transfer efficiency of photo-generated charges.

FIG. 4 is a design structure of a pixel unit provided by the present invention, wherein the photoelectric conversion area 401 converts the returned light reflected in the field of view to obtain photo-generated charge information. In order to adjust the potential barrier between the conversion region 401 and the two floating

diffusion regions

4031 and 4032 for delayed reception using complementary phases, the pixel unit further includes a potential barrier adjustment region 406 . The main function of the potential barrier adjustment region is to adjust the potential barrier between the conversion region 401 and the floating diffusion node, so that the potential barrier is lower than that in the prior art solution. The barrier adjustment region can use the same doping as the conversion region (including the same type and the same doping production process and final doping concentration, etc.), that is, the barrier adjustment region can be included in the control part covered within the area. In this embodiment, the potential barrier adjustment region is in contact with the P-well region surrounding the floating diffusion node or is spaced by a predetermined gap, and the predetermined gap is set so that the potential barrier between the floating control node and the conversion region is controlled In the lower value range, eg around 0.8V. Of course, the size of the potential barrier can be adjusted by adjusting the size of the preset gap, so that the value of the potential barrier is at an appropriate size, so as to ensure that the photo-generated charges can be properly blocked between the floating diffusion node and the conversion region, so as to ensure that the entire detection accuracy. In addition, since the barrier adjustment region 406 is provided to reduce the potential barrier between the conversion region 401 and the floating diffusion node 403 (including the two complementary delay phase floating diffusion nodes 4031 and 4032 ), the control part 402 can be selected as The MOS type transistor, which may be an NMOS type or a PMOS type transistor, is not limited here. By applying a small voltage on the control part 402, the potential barrier voltage difference needs to be higher than that of the structure, so optimally, a voltage of 1-1.5V is selected to be applied to the gate of the control part, and the conversion region to floating The potential barrier between the control nodes can be changed in a larger influence range, and the control voltage applied to the gate of the control part is lower than that of the control part to build a communication channel between the photoelectric conversion region and the floating diffusion node channel control voltage. The control part changes the potential barrier between the conversion region and the floating diffusion node by adjusting the control voltage of the gate, so as to realize the establishment of a potential barrier influence region between the conversion region and the floating diffusion node Instead of the channel region of the charge transfer, the photo-generated charge can be transferred from a larger area to the floating diffusion node, rather than only through the channel transfer in the prior art, and the photo-generated charge can also be transferred through the The optimized path realizes the effect of transferring to the floating diffusion node nearby, which ensures the speed and efficiency of photo-generated charge transfer. On the other hand, due to the existence of the potential barrier adjustment region, the voltage applied to the gate of the control part becomes about half of the previous voltage, which ensures that the entire pixel unit consumes less energy and generates less heat during the operation of the entire pixel unit. A region near the surface includes a first-type doping region, and the coverage region under the gate of the control portion also includes a first-type doping region with a smaller doping concentration, and the first-type doping region has a doping concentration higher to ensure that the photo-generated charge of the entire pixel unit can be clamped without overflow and other interference. The photoelectric conversion region adopts N-type doping including doping group 5/V elements (phosphorus, arsenic, antimony, bismuth, etc.), The first type of doped region includes doping of Group 3/III elements (boron, aluminum, gallium, indium, etc.), the floating diffusion node is disposed in a P-well, and the P-well includes P-type doping. In order to adapt to the structure of the photoelectric conversion region, the P well can be set to have a concentration gradient structure, for example, the P well 404 contains two different concentrations of P doping. In order to ensure the strong resistance of the floating diffusion node to interference such as background light, the doping concentration of the P type in the

regions

40411 and 40421 is higher than the doping concentration of the P type in the

regions

40412 and 40422 . In order to ensure reliable isolation between pixels, the P-well is connected to a trench, which can physically ensure that the photo-generated charges between the pixels will not interfere with each other, thereby ensuring the reliability of the device. Further, a spacer is included between the control part and the floating diffusion node, which can ensure a certain space between the floating diffusion node and the P-well region connected to the isolation part, thereby further reducing the distance between the photoelectric conversion region and the floating diffusion node. barrier between.

FIG. 5 is another design structure of a pixel unit provided by the present invention, which is different from FIG. 4 in that the potential barrier adjustment region is connected to the floating diffusion node or to the peripheral P-well region, so that the conversion can be guaranteed. There is a certain potential barrier between the region and the floating diffusion node, but the potential barrier will not be too large, so as to meet the effect of reducing the potential barrier to the preset target. Other structures that are the same as Figure 4 have similar functions. It is not repeated here.

FIG. 6 is a schematic diagram of the current flow of this type of pixel unit when a certain gate voltage is applied to both control parts. It can be seen from the figure that under the condition that the gate of the control part has a voltage, the current in the conversion region can be Flow to the floating diffusion node region through more different paths, which is also the optimal effect to be achieved by the present invention, which can achieve the effect of transferring photo-generated charges more quickly and efficiently, and the current path is not a traditional concentrated conversion channel region.

FIG. 7 illustrates the comparison of the potential after the adjustment of the solution including the potential adjustment region in the pixel unit of the present invention and the potential of the prior art. As shown in the figure, the adjusted potential barrier will be greatly reduced, so that its threshold voltage will be greatly reduced, which ensures that the operating voltage of the pixel unit is lower and the transfer efficiency is higher.

8 is the actual simulation results in different states illustrated in the present invention, wherein the uppermost schematic diagram is a schematic diagram of the potential distribution in the pixel unit in which the two control parts do not apply any control voltage in the structure of the present invention. It can be seen from this figure, When no voltage is applied, there is a certain potential barrier between the floating diffusion nodes FDA and FDB and the conversion region, and even if there is a photo-generated charge, it will not be transferred to the floating diffusion node. In addition, the middle diagram shows the potential distribution when the control voltage is applied to the two control parts. The control part is equivalent to changing the equipotential line distribution, thereby opening the transmission path from the conversion region to the floating diffusion node in a larger area. In addition, the bottom schematic diagram shows a schematic diagram in which one control part PGA is not applied with a voltage, while the other control part PGB is applied with a control voltage. The control effect of complementary delay reception is realized.

FIG. 9 is a schematic diagram of the potential distribution at a cross section in different states of FIG. 8 , wherein 910 corresponds to the uppermost schematic diagram in FIG. 8 , 920 is the result shown in the middle diagram in FIG. 8 , and 930 is the result shown in the lowermost diagram .

It should be noted that the terms "comprising", "comprising" or any other variation thereof are intended to encompass a non-exclusive inclusion such that a process, method, article or device comprising a series of elements includes not only those elements, but also no Other elements expressly listed, or which are also inherent to such a process, method, article or apparatus. Without further limitation, an element qualified by the phrase "comprising a..." does not preclude the presence of additional identical elements in a process, method, article or apparatus that includes the element.

The above descriptions are only preferred embodiments of the present application, and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this application shall be included within the protection scope of this application. It should be noted that like numerals and letters refer to like items in the following figures, so once an item is defined in one figure, it does not require further definition and explanation in subsequent figures. The above descriptions are only preferred embodiments of the present application, and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this application shall be included within the protection scope of this application.

Claims

A distance information acquisition sensor of a potential barrier adjustment type, including:

a semiconductor substrate, including a conversion region for converting optical signals into photo-generated charges; and

a first-type doped region disposed in a region near a surface of the semiconductor body, wherein

The doping type of the conversion region is different from that of the first-type doping region, the first-type doping region extends to a partial area of a surface of the semiconductor body and is connected to the gate of the control portion, and the conversion region The region includes a barrier adjustment region that is in contact with or spaced apart by a predetermined gap with the P-well region surrounding the floating diffusion node.
The barrier adjustment type distance information acquisition sensor according to claim 1, wherein the number of the control parts is two or more, and the control parts are MOS type transistors.
The distance information acquisition sensor of a potential barrier adjustment type according to claim 1 or 2, wherein the control section is adapted to adjust the potential of the photo-generated charges generated in the conversion region to the floating diffusion node to change the photo-generated charges resistance to movement.
According to the distance information acquisition sensor of the potential barrier adjustment type according to claim 3, the voltage range applied to the gate of the control part is 1V-1.5V.
The barrier adjustment type distance information acquisition sensor according to claim 1, wherein the P-well region is further connected with an isolation portion defining the conversion region to form a pixel unit.
The barrier adjustment type distance information acquisition sensor according to claim 1, wherein the doping type of the conversion region is N-type doping, and the doping type of the first doping region is P-type doping.
The barrier adjustment type distance information acquisition sensor according to claim 6, wherein the first doping region is provided with a clamping region for clamping the photo-generated charges, and the P-type doping concentration in the clamping region is greater than the P-type doping concentration in the first doping region.
The distance information acquisition sensor of the barrier adjustment type according to claim 1, wherein the control voltage applied to the gate of the control part is lower than the connection established by the control part between the conversion region and the floating diffusion node control voltage of the channel.
The distance information acquisition sensor of the potential barrier adjustment type according to claim 1, wherein the control part changes the potential barrier between the conversion region and the floating diffusion node by adjusting the control voltage of the gate, so that the A photo-generated charge transfer region forming a potential barrier influence region is formed between the conversion region and the floating diffusion node.
The barrier adjustment type distance information acquisition sensor according to claim 1, wherein a spacer is provided between the control portion and the floating diffusion node.
A detection system comprising:

a light source to illuminate the field of view; and

A receiving module including a distance information acquisition sensor of a potential barrier adjustment type, the distance information acquisition sensor of the potential barrier adjustment type comprising a semiconductor substrate and a first-type doped region disposed in a region near a surface of one of the semiconductor substrates, so The semiconductor substrate includes a conversion region for converting the return light signal of the light source in the field of view into photo-generated charges, the conversion region has a different doping type from the first-type doping region, and the first-type doping region is doped. The impurity region extends to a partial region of one surface of the semiconductor body and is connected to the gate of the control portion, the conversion region includes a barrier adjustment region, and the barrier adjustment region is in contact with the P-well region surrounding the floating diffusion node or interval preset gaps.
The detection system according to claim 11 , wherein the control part is adapted to adjust the potential of the photo-generated charges generated in the conversion region to the floating diffusion node, so as to change the resistance to the movement of the photo-generated charges.
The detection system according to claim 12, wherein the voltage range applied to the gate of the control part is 1V-1.5V.
The detection system according to claim 11, wherein the doping type of the conversion region is N-type doping, and the doping type of the first doping region is P-type doping.
The detection system according to claim 11 , the control voltage applied to the gate of the control part is lower than the control voltage of the communication channel constructed by the control part between the conversion region and the floating diffusion node.
The detection system according to claim 11 , wherein the control part changes a potential barrier between the conversion region and the floating diffusion node by adjusting the control voltage of the gate, so as to change the potential barrier between the conversion region and the floating diffusion node. A photo-generated charge transfer region that forms a barrier influence region is constructed between the diffusion nodes.
An electronic device including a distance information acquisition sensor of the barrier adjustment type as claimed in claim 1 .