Image sensor, manufacturing method, imaging method, and electronic device

Abstract

The application discloses an image sensor, a preparation method, an imaging method and an electronic device, and relates to the technical field of image sensors.The image sensor comprises first-type pixels and second-type pixels;the light ray configuration structure comprises a light shielding part located on the upper side of the first-type pixels and a first-type barrier wall located between the first-type pixels and the second-type pixels in response to different types of light signals;based on the light ray configuration structure, incident light enters the area corresponding to the second-type pixels and generates derived light, and the derived light enters the first-type pixels adjacent to the second-type pixels and responding to the same type of light signal.The application can obtain the same light signal based on the first-type pixels and the second-type pixels, so that the dynamic range of the image is improved, and the acquisition of a photo or a video with light source flicker is effectively realized.In addition, the first-type barrier wall can effectively prevent the mutual crosstalk of different types of light signals between the first-type pixels and the second-type pixels in response to different types of light signals, and improve the imaging effect of the first-type pixels.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of image sensors, and in particular to an image sensor, a preparation method, an imaging method and an electronic device. BACKGROUND

[0002] An image sensor refers to a device for converting optical signals into electrical signals. Commonly used image sensor chips include charge-coupled devices (CCD) and complementary metal-oxide semiconductor (CMOS) image sensor chips.

[0003] Compared with traditional CCD sensors (charge-coupled devices), CMOS image sensors (CIS) have the characteristics of low power consumption, low cost and compatibility with CMOS processes, and thus are increasingly widely used. CMOS image sensors are now not only used in consumer electronics, such as digital still cameras (DSC), mobile phone cameras, camcorders and digital single-lens reflex cameras (DSLR), but also widely used in automotive electronics, monitoring, biotechnology and medicine.

[0004] A pixel unit of a CMOS image sensor is a core device for realizing photosensing of the image sensor. The most commonly used pixel unit is an active pixel structure including a photodiode and multiple transistors. The photodiode in these devices is a photosensing unit, which realizes collection and photoelectric conversion of light, and the other MOS transistors are control units, which realize selection, reset and signal readout control of the photodiode.

[0005] CMOS image sensors can be divided into front-side illumination (FSI) and back-side illumination (BSI) image sensors according to the path of incident light into the photodiode. Front-side illumination refers to an image sensor in which incident light enters the photodiode from the side close to the circuit connection layer, while back-side illumination refers to an image sensor in which incident light enters the photodiode from the side away from the circuit connection layer.

[0006] However, in some applications, it's necessary to capture photos or videos of flickering light sources. For example, in vehicle monitoring, some image sensors need to monitor scenes outside the vehicle, including traffic lights. Traffic lights are typically flickering LEDs, requiring the chip to have a sufficiently long exposure time to cover the LED's flicker cycle and capture the "bright" image information. In this scenario, pixels exposed for a long time cannot be overexposed. However, scenes outside the vehicle also contain bright signals, such as the light at tunnel exits, the sun in the sky, and headlights of nearby cars. To prevent these bright signals from being lost in the monitoring image, the image sensor needs a shorter exposure time, which contradicts the requirement to capture flickering LED information. Therefore, the chip needs another method, LFM (Light Flicker Mitigation), i.e., LED flicker suppression, to prevent overexposure of bright scenes while still capturing the relatively long flicker period of the LED signal. In other cases, CMOS image sensors need to capture scenes with a large dynamic range to obtain clear images from low-light to bright-light conditions. Therefore, the image sensor needs to have a large dynamic range.

[0007] In existing technologies, light transmission (LFM) is achieved by adding anti-reflection materials to some normal pixels to reduce light transmittance, while controlling the exposure time of these pixels to cover the LED flicker cycle. However, the drawback is that these pixels have relatively weak anti-crosstalk capabilities. The effective signal collected in these pixels from the front is less, but the proportion of crosstalk signals from the surrounding area in the total signal is increased, thus affecting the imaging effect of these pixels and the subsequent image synthesis with normal pixels. Summary of the Invention

[0008] In order to overcome the shortcomings and deficiencies of the prior art, the present invention aims to provide an image sensor, a preparation method, an imaging method, and an electronic device to solve the problem that the image sensor in the prior art will reduce its anti-crosstalk capability when the dynamic range is increased.

[0009] The objective of this invention is achieved through the following technical solution:

[0010] This invention provides an image sensor, comprising:

[0011] The first type of pixels includes a first photosensitive area;

[0012] The second type of pixel includes a second photosensitive area, and the first type of pixel and the second type of pixel are spaced apart from each other;

[0013] The light configuration structure includes a light-shielding part and a first-class barrier;

[0014] The light shielding part is located on the upper side of the first type of pixel to shield the incident light from entering the first photosensitive area; the first type of barrier wall is located between the first type of pixel and the second type of pixel in response to different types of light signals, to shield the derived light of the second type of pixel from entering the first type of pixel in response to different types of light signals;

[0015] Based on the light configuration structure, the incident light enters the area corresponding to the second type of pixel and generates derived light, which enters the first type of pixel adjacent to the second type of pixel in response to the same type of light signal, wherein the first photosensitive area receives the derived light to generate a first signal, and the second photosensitive area receives the incident light to generate a second signal.

[0016] Further, the light configuration structure further comprises a second type of barrier wall, which is located between the first type of pixel and the second type of pixel in response to the same type of light signal, to reduce the derived light of the second type of pixel from entering the first type of pixel in response to the same type of light signal.

[0017] Further, the depth of the second type of barrier wall is less than the depth of the first type of barrier wall.

[0018] Further, the second type of barrier wall comprises a plurality of barrier walls, and adjacent two of the barrier walls have a light-transmitting gap therebetween.

[0019] Further, the light shielding part, the second type of barrier wall and the first type of barrier wall all adopt light-blocking materials to prevent light transmission.

[0020] Further, the light shielding part and the first type of barrier wall adopt light-blocking materials to prevent light transmission, and the second type of barrier wall adopts a light-reducing material to reduce the light transmission rate of the second type of barrier wall.

[0021] Further, when the light shielding part, the second type of barrier wall and the first type of barrier wall all adopt light-blocking materials, the light shielding part, the second type of barrier wall and the first type of barrier wall are made of the same material, or the second type of barrier wall and the first type of barrier wall are made of the same material and different from the material of the light shielding part.

[0022] Further, the light shielding rate of the light configuration structure is greater than or equal to 98%.

[0023] Further, the first type of pixel and the second type of pixel have the same shape and size and are arranged in a periodic array, or the first photosensitive area of the first type of pixel has a smaller area than the second photosensitive area of the second type of pixel.

[0024] Further, the image sensor comprises a metal grid, and the light shielding part is arranged in the same layer as the metal grid.

[0025] Further, the image sensor comprises a color filter and a flat layer at least filled between the light-shielding portions, the color filter being covered on the flat layer.

[0026] Further, the image sensor comprises a color filter, the first type of pixels and the second type of pixels adjacent and responding to the same type of light signal are covered with the color filter of the same color, so that each of the first type of pixels and the corresponding second type of pixels respond to the same type of light signal.

[0027] Further, the color filter is only arranged in the area corresponding to the second type of pixels.

[0028] Further, the microlens is only arranged in the area corresponding to the second type of pixels.

[0029] Further, in the first type of pixels and the second type of pixels adjacent and responding to different types of light signals, the first type of pixels is covered with the color filter of the same color as the second type of pixels on the side close to the second type of pixels.

[0030] Further, the color filter of the second type of pixels extends to the center of the first type of pixels responding to different types of light signals.

[0031] Further, the image sensor comprises a plurality of pixel units, each of the pixel units comprises a first color pixel subunit, a second color pixel subunit and a third color pixel subunit, wherein the pixel subunit of at least one color comprises at least one of the first type of pixels and at least one of the second type of pixels.

[0032] Further, the pixel structure further comprises an auxiliary light distribution structure, the auxiliary light distribution structure is arranged on the side of the second type of pixels away from the incident light, the incident light passing through the second type of pixels is modulated into the first type of pixels via the auxiliary light distribution structure to obtain modulated light, and the first type of pixels obtains the first signal based on the modulated light and the derived light.

[0033] Further, the auxiliary light distribution structure comprises a plurality of auxiliary light distribution substructures, and the light ray configuration structure comprises a second type of barrier wall, in the direction away from the second type of barrier wall, each of the auxiliary light distribution substructures is staggered with each other and is arranged in turn away from the second light-sensitive area of the corresponding second type of pixels.

[0034] The application also provides an electronic device comprising the image sensor as described above.

[0035] The application also provides a preparation method of the image sensor as described above, the preparation method comprising the following steps:

[0036] providing a substrate;

[0037] preparing the first type of pixels and the second type of pixels in the substrate;

[0038] preparing the light configuration structure on the substrate, the light configuration structure comprising a light shielding part and a first type of barrier wall, the light shielding part being located on the upper side of the first type of pixels to shield incident light from entering the first light sensing area; the first type of barrier wall being located between the first type of pixels and the second type of pixels in response to different types of light signals, to shield the derived light of the second type of pixels from entering the first type of pixels in response to different types of light signals.

[0039] Further, the image sensor comprises a metal grid, the light shielding part and the metal grid are made of the same material and by the same process.

[0040] Further, the pixel structure further comprises the auxiliary light distribution structure, the auxiliary light distribution structure and the interconnection wiring structure are prepared based on the same process.

[0041] The application also provides an imaging method based on the image sensor as described above, the imaging method comprising the following steps:

[0042] controlling the first type of pixels to have a first exposure time, and the second type of pixels to have a second exposure time, and the first exposure time being greater than the second exposure time.

[0043] The application has the advantages that: by setting the first type of pixels and the second type of pixels, and the upper side of the first type of pixels being provided with a light shielding part, and the first type of barrier wall being provided between the first type of pixels and the second type of pixels in response to different types of light signals, the first type of pixels are based on the derived light of the second type of pixels as response light, so that the first type of pixels receive the same type of derived light to generate a first signal, while the second type of pixels generate a second signal based on incident light, so that an effective image signal can be obtained based on the first signal of the first type of pixels and the second signal of the second type of pixels, to improve the dynamic range of the image, and effectively realize the acquisition of a photo or video with light source flicker, and the effective acquisition of the photo or video with light source flicker can be realized based on the first signal and the second signal. In addition, the first type of barrier wall can shield the derived light of the second type of pixels from entering the first type of pixels in response to different types of light signals, effectively preventing the mutual crosstalk of different types of light signals between the first type of pixels and the second type of pixels in response to different types of light signals, improving the imaging effect of the first type of pixels, and facilitating the subsequent synthesis of a normal image with the second type of pixels in response to the same type of light signal. BRIEF DESCRIPTION OF DRAWINGS

[0044] Figure 1is a basic structural block diagram of an image sensor system;

[0045] Figure 2 is a pixel circuit diagram of an image sensor;

[0046] Figure 3 is a cross-sectional structural diagram of an image sensor in embodiment one of the present application;

[0047] Figure 4 is a planar structural diagram of an image sensor in embodiment one of the present application;

[0048] Figure 5 is a planar structural diagram of an image sensor in embodiment one of the present application;

[0049] Figure 6 is a planar structural diagram of an image sensor in embodiment one of the present application;

[0050] Figures 7a-7i is a cross-sectional structural diagram of an image sensor in embodiment one of the present application;

[0051] Figures 8a-8d is a cross-sectional structural diagram of an image sensor in embodiment one of the present application;

[0052] Figure 9 is a cross-sectional structural diagram of an image sensor in embodiment two of the present application;

[0053] Figures 10a-10e is a cross-sectional structural diagram of an image sensor in embodiment two of the present application;

[0054] Figure 11 is a cross-sectional structural diagram of an image sensor in embodiment three of the present application;

[0055] Figure 12 is a planar structural diagram of an image sensor in embodiment three of the present application;

[0056] Figure 13 is a planar structural diagram of an image sensor in embodiment three of the present application;

[0057] Figure 14 is a planar structural diagram of an image sensor in embodiment three of the present application;

[0058] Figure 15 is a cross-sectional structural diagram of an image sensor in embodiment four of the present application;

[0059] Figure 16 is a cross-sectional structural diagram of an image sensor in embodiment five of the present application;

[0060] Figure 17 is a schematic diagram of a cross-sectional structure of an image sensor in Embodiment Six of the present application. DETAILED DESCRIPTION

[0061] In order to further clarify the technical means and effects taken by the present application to achieve the predetermined object, the specific embodiments, structures, features and effects of the image sensor, the preparation method, the imaging method and the electronic device according to the present application are described in detail below in combination with the drawings and preferred embodiments:

[0062] Figure 1 is a basic circuit schematic diagram of an image sensor. As shown in Figure 1 , the image sensor 100 includes a reading circuit 104 connected to a pixel array 102 and a control circuit 108, and a functional logic circuit 106 connected to the reading circuit 104 for logically controlling the reading of the pixel circuit; the reading circuit 104 and the control circuit 108 are connected to a state register 112 to realize the reading control of the pixel array 102. The pixel array 101 includes a plurality of pixel units in rows (R1, R2, R3…Ry) and columns (C1, C2, C3…Cx), and the pixel signals output by the pixel array 102 are output to the reading circuit 104 through the column line.

[0063] In an embodiment, after each pixel unit acquires image data, the image data is read out by the reading circuit 104 specified by the state register 112 in the readout mode, and then transmitted to the functional logic circuit 106. In a specific application, the reading circuit 104 can include an analog-to-digital conversion (ADC) circuit, an amplification circuit and others. In some application embodiments, the state register 112 can include a programmed selection system to determine whether the readout system is read out by a rolling shutter or a global shutter. The functional logic circuit 106 can only store the image data or process the image data through image effect application. In an application example, the reading circuit 104 can read out one row of image data along the readout column line at a time, or can read out the image data in various other ways. The operation of the control circuit 108 can be determined by the current setting of the state register 112. For example, the control circuit 108 generates a shutter signal for controlling image acquisition. In some application examples, this shutter signal can be a global exposure signal to make all pixels of the pixel array 102 acquire their image data simultaneously through a single acquisition window. In some other application examples, this shutter signal can be a rolling exposure signal to realize continuous reading operation of each pixel row through the acquisition window.

[0064] Figure 2 is a schematic diagram of a pixel circuit of an image sensor, which can show the connection diagram of a transistor in the image sensor. As shown in Figure 2As shown, each sensor pixel circuit 200 includes a light sensing element 210 (e.g., a photodiode) and a pixel support circuit 211. The photodiode 210 can be a buried photodiode as used in current image sensors. In one application, the pixel support circuit 211 includes a reset transistor (RST) 220, a source follower (SF) transistor 225, and a row select transistor (RS) 230 connected to a transfer transistor (TX) 215 and the photodiode 210 as shown. In another application, not shown, the pixel support circuit 211 includes the reset transistor 220, the source follower transistor 225, and the row select transistor 230 disposed on one circuit chip, and the photodiode 210 is connected to the transfer transistor 215 based on another chip. During operation, the photodiode 210 generates photocharges in response to incident light during an exposure period. The transfer transistor 215 is connected to a transfer signal that controls the transfer transistor 215 to transfer the accumulated charges in the photodiode 210 to a floating diffusion region (FD) 217. In one embodiment, the transfer transistor 215 can be a MOSFET (Metal Oxide Semiconductor Field Effect Transistor). The reset transistor 220 is connected between VDD and the floating diffusion region 217 to reset the sensor pixel circuit 200 (e.g., discharge or charge the floating diffusion region 217 and the photodiode 210 to a current voltage) in response to a reset signal RST. The floating diffusion region 217 is connected to the gate of the source follower transistor 225. The source follower transistor 225 is connected between VDD and the row select transistor 230 to respond to and output the potential of the floating diffusion region 217. The row select transistor 230 connects the pixel circuit output from the source follower transistor 225 to a readout column, or bit line 235, in response to a row select control signal.

[0065] [Embodiment One]

[0066] Figure 3 is a cross-sectional view of an image sensor according to an embodiment of the present application. Figure 4 is a plan view of an image sensor according to an embodiment of the present application. Figure 5 is a plan view of an image sensor according to an embodiment of the present application. Figure 6 is a plan view of an image sensor according to an embodiment of the present application. Figures 3 to 6 As shown, an image sensor according to an embodiment of the present application includes:

[0067] a first type of pixel P1 including a first light sensing region P11 and a second type of pixel P2 including a second light sensing region P21, and the first type of pixel P1 and the second type of pixel P2 are spaced apart from each other.

[0068] The light configuration structure includes the light shielding part 512 and the first type of blocking wall 410. The light shielding part 512 is located on the upper side of the first type of pixel P1 to shield the incident light from entering the first light sensing area P11. In an embodiment, the size of the light shielding part 512 is greater than or equal to the size of the corresponding first type of pixel P1, which is beneficial to completely shield the first type of pixel P1 and avoid the direct light from entering the first light sensing area P11 of the first type of pixel P1. The first type of blocking wall 410 is located between the first type of pixel P1 and the second type of pixel P2 in response to different types of light signals to shield the derived light of the second type of pixel P2 from entering the first type of pixel P1 in response to different types of light signals.

[0069] It should be noted that the first type of pixel P1 in the present application refers to a type of pixel with a light shielding part 512 formed on the upper side, and the second type of pixel P2 refers to a pixel without a light shielding part 512 formed on the upper side and can provide a light source (derived light generated after the incident light enters) for the first type of pixel P1 adjacent to the first type of pixel P1 in response to the same type of light signal. In addition, for the derived light, after the incident light enters the second type of pixel P2, the pixel generates, for example, diffraction of the incident light, and the diffraction light enters the first type of pixel P1, and this part of the diffraction light constitutes the derived light.

[0070] Based on the light configuration structure, the incident light enters the area corresponding to the second type of pixel P2 and generates derived light, and the derived light enters the first type of pixel P1 adjacent to the second type of pixel P2 in response to the same type of light signal, wherein the first light sensing area P11 receives the derived light to generate a first signal, and the second light sensing area P21 receives the incident light to generate a second signal, and the first signal and the second signal are the same type of light signal.

[0071] In addition, it should be noted that the "same type of light signal" here can refer to the same color of light obtained after passing through the same color filter 520, for example, the second type of pixel P2 provided with a red color filter, so that the second type of pixel P2 responds to red light, and the first type of pixel P1 adjacent to the second type of pixel P2 in response to the same type of light signal also responds to the red light signal obtained by the derived light. In addition, it can also be provided with a green color filter, a blue color filter, an infrared color filter, cyan, yellow, magenta, or no color filter 520, and visible light signals can be collected. Of course, the "same type of light signal" can also be other settings of the second type of pixel P2 according to actual needs, for example, set as a pixel that transmits infrared light. In addition, the first type of pixel P1 and the second type of pixel P2 are spaced apart from each other, which can be understood as that the two respectively acquire image signals, and of course, the isolation between the two can also be configured as the existing isolation between the pixels of the image sensor.

[0072] Based on the above design, the first type of pixels P1 uses the derived light of the second type of pixels P2 as response light, so that the first type of pixels P1 receives the same type of derived light, and the first type of pixels P1 only uses the derived light of the second type of pixels P2 to obtain image information to generate a first signal, while the second type of pixels P2 generates a second signal based on incident light, so that an effective image signal can be obtained based on the first signal of the first type of pixels P1 and the second signal of the second type of pixels P2, to improve the dynamic range of the image, and effectively realize the acquisition of a photo or video with light source flicker, and the effective acquisition of a photo or video with light source flicker can be realized based on the first signal and the second signal.

[0073] In the present application, the light configuration structure further comprises a second type of baffle wall 420, which is located between the first type of pixels P1 and the second type of pixels P2 that respond to the same type of light signal, to reduce the derived light of the second type of pixels P2 from entering the first type of pixels P1 that respond to the same type of light signal. Based on the design of the second type of baffle wall 420, the present application can further reduce the amount of derived light entering the first type of pixels P1, thereby further improving the dynamic range of the image and realizing the acquisition of a photo or video with higher frequency light source flicker. It should be noted that the amount of derived light entering the first type of pixels P1 can be adjusted according to actual needs, for example, if the amount of derived light entering the first type of pixels P1 needs to be a little more, then the light reduction effect of the second type of baffle wall 420 needs to be a little less, and vice versa.

[0074] In the present embodiment, the second type of baffle wall 420 reduces the amount of derived light entering the first type of pixels P1 in the following way: the depth of the second type of baffle wall 420 is less than the depth of the first type of baffle wall 410. The first type of baffle wall 410 is used to block the derived light of the second type of pixels P2 from entering the first type of pixels P1 that respond to different types of light signals, and for this purpose, the upper end of the first type of baffle wall 410 needs to be connected with the light shielding part 512, and the other end needs to penetrate the semiconductor structure layer 400. The depth of the second type of baffle wall 420 is less than the depth of the first type of baffle wall 410, so the second type of baffle wall 420 does not need to penetrate the semiconductor structure layer 400, and the depth of the second type of baffle wall 420 is less than the thickness of the semiconductor structure layer 400.

[0075] The light shielding part 512, the second type of barrier wall 420, and the first type of barrier wall 410 are all made of light shielding material to prevent light from penetrating. The light shielding part 512, the second type of barrier wall 420, and the first type of barrier wall 410 are all made of the same light shielding material; or the second type of barrier wall 420 and the first type of barrier wall 410 are made of the same light shielding material, and the light shielding material of the light shielding part 512 is different. In an embodiment, the light shielding rate of at least one of the light shielding part 512, the first type of barrier wall 410, and the second type of barrier wall 420 in the light configuration structure is greater than or equal to 98%, for example, the light shielding rate can be 99% or 100%, which can be obtained by experimental testing experience, etc.

[0076] As an example, a design of a pixel layout with an RGGB filter, in which, as shown in Figure 4 and 5 , the area of the first light sensing area P11 of the first type of pixel P1 is smaller than the area of the second light sensing area P21 of the second type of pixel P2, so that the amount of light entering the first type of pixel P1 can also be reduced. The shape of the first type of pixel P1 can be rectangular or prismatic. Alternatively, as shown in Figure 6 , the shape and size of the first type of pixel P1 and the second type of pixel P2 are the same and periodically arrayed.

[0077] In an example, the image sensor includes a plurality of pixel units, each pixel unit including a first color pixel subunit, a second color pixel subunit, and a third color pixel subunit, wherein the pixel subunit of at least one color includes at least one first type of pixel P1 and at least one second type of pixel P2. In other embodiments, the pixel unit can be a transparent pixel unit, an IR (infrared) pixel unit, a yellow pixel unit, a cyan pixel unit, a magenta pixel unit. For example, as shown in Figure 4 and Figure 5 , two B pixels with different light sensing areas constitute a pixel subunit, and similarly, two G pixels and R pixels with different light sensing areas constitute different pixel subunits; Figure 6 , four B pixels with the same shape and size constitute a pixel subunit, and similarly, four G pixels and R pixels with the same shape and size constitute different pixel subunits.

[0078] Further, the image sensor includes a metal grid 511, and the light shielding part 512 is disposed in the same layer as the metal grid 511. The light shielding part 512 and the metal grid 511 can be made of the same material and manufactured by the same etching process. Of course, the light shielding part 512 and the metal grid 511 can also be made of different materials and manufactured by different etching processes.

[0079] In an embodiment, the image sensor comprises a planar layer 502 filling at least between the light shielding portions 512, thereby playing a planarization role for the light shielding portions 512 and the metal grating 511, and the color filter 520 is arranged on the planar layer 502. In other embodiments, the color filter 520 can be embedded between adjacent metal gratings 511. In this case, the first type of pixels P1 and the second type of pixels P2 adjacent to each other are covered with color filters 520 of the same color in response to the same type of light signal, so that each first type of pixel P1 and the corresponding second type of pixel P2 respond to the same type of light signal. Alternatively, the color filter 520 is arranged only in the area corresponding to the second type of pixel P2, i.e. the upper side of the first type of pixel P1 does not need to be configured with the color filter 520. Of course, the upper side of the first type of pixel P1 can also not be configured with the microlens 530.

[0080] Further, the image sensor comprises the circuit connection layer 300, the optical structure layer 500, and the semiconductor structure layer 400 between the circuit connection layer 300 and the optical structure layer 500. In this case, the first light sensing region P11 of the first type of pixel P1, the second light sensing region P21 of the second type of pixel P2, the first type of barrier wall 410, and the second type of barrier wall 42 are arranged in the semiconductor structure layer 400. The metal grating 511, the light shielding portion 512, the color filter 520, and the microlens 530 are arranged in the optical structure layer 500. The circuit connection layer 300 is configured with the first gate layer 311 corresponding to the first type of pixel P1, the second gate layer 312 corresponding to the second type of pixel P2, and a plurality of conductive circuits, one end of the conductive circuit being conductively connected to the gate layer. Of course, in practice, the circuit connection layer 300 further comprises other structures to form a transfer transistor (MTX), a reset transistor (MRS), an amplification transistor (MRD), and other circuits, which will not be described in detail here.

[0081] Figures 7a-7i is one of the cross-sectional structure schematic diagrams of the image sensor manufacturing process in Embodiment One of the present application, which is illustrated by taking a BSI structure image sensor as an example. The present application provides a preparation method for manufacturing the image sensor as described above, which comprises the following steps:

[0082] As shown in Figure 7a , a substrate 440a is provided.

[0083] Specifically, the substrate 440a can be any structure used for manufacturing various functional regions of the image sensor in the field of image sensors, such as the light sensing elements and various control transistors of the CMOS image sensor based on the substrate 440a. In this case, the substrate 440a can be a structure composed of a single material layer, including but not limited to a silicon substrate, and the elements in each region are manufactured in the silicon substrate, which can be single crystal silicon, single crystal germanium, polycrystalline silicon, amorphous silicon, silicon germanium compound, etc.

[0084] In addition, the substrate 440a can also be a laminated structure composed of two or more material layers, and each region is prepared in any required layer. For example, the substrate 440a includes a silicon substrate and an epitaxial layer (EPI) formed on the silicon substrate, and the photosensitive element and each control transistor are prepared in the epitaxial layer. For example, a backside illumination (BSI) image sensor can be prepared based on the above structure. In addition, the substrate 440a can also be a silicon on insulator (SOI). In addition, the substrate 440a can also be a structure with N-type doping or P-type doping to meet the functional requirements of the device.

[0085] In an example, the substrate 440a has opposite first and second surfaces. In an optional example, the first and second surfaces can be opposite front and back surfaces of the substrate 440a, for example, the front and back surfaces of a silicon substrate. In other examples, the first surface can be formed by a surface of an epitaxial layer formed on the substrate 440a, and the second surface can be formed by another surface of the substrate 440a away from the epitaxial layer.

[0086] The circuit connection layer 300 is prepared on the front surface of the substrate 440a, and the circuit connection layer 300 is configured with a first gate layer 311 corresponding to the first type of pixel P1, a second gate layer 312 corresponding to the second type of pixel P2, and a plurality of conductive lines, one end of the conductive line being conductively connected to the gate layer. Of course, in practice, the circuit connection layer 300 also includes other structures to form a transfer transistor (MTX), a reset transistor (MRS), an amplification transistor (MRD), and other circuits, which will not be described in detail here. The circuit connection layer 300 can be prepared by using existing structures and processes, and the interconnection of each transistor can be realized based on the circuit connection layer 300. The circuit connection layer 300 can include a metal layer and a dielectric layer.

[0087] In addition, the first type of pixel P1 and the second type of pixel P2 can also be prepared on the substrate 440a. The first type of pixel P1 includes a first photosensitive region P11, and the second type of pixel P2 includes a second photosensitive region P21.

[0088] Specifically, the first type of pixel P1 and the second type of pixel P2 can be pixels (Pixel) in a conventional image sensor chip. The first photosensitive region P11 and the second photosensitive region P21 can receive a light signal and generate photoelectrons. In an example, the first photosensitive region P11 and the second photosensitive region P21 include a photodiode, which can be a PPD (Pinned Photodiode Pixel) structure. Of course, the first photosensitive region P11 and the second photosensitive region P21 can also be other structures that can convert a light signal into an electrical signal.

[0089] In addition, the first type of pixel P1 and the second type of pixel P2 can further include other transistor structures and the like, such as a field effect transistor electrically connected with the photodiode. For example, taking the first type of pixel P1 as an example, the first type of pixel P1 can further include a transfer transistor TX with a transfer gate. In another example, a floating diffusion node FD is further formed in the first type of pixel P1, and of course, other field effect transistors, such as a reset transistor RST, a source follower transistor SF, and a row select transistor RS, can be further included to form a 3T, 4T, 5T, or the like pixel structure. The type of each of the above-mentioned transistors is selected as N-type in this embodiment, and it can be understood that it can also be P-type in an implementation. Similarly, the second type of pixel P2 can also have a similar arrangement. In addition, the number and arrangement of the internal transistors of the first type of pixel P1 and the second type of pixel P2 can be designed according to actual needs, and are not limited here.

[0090] As shown in FIG. 4A, a light ray configuration structure is prepared on the substrate 440a. Figures 7b-7g

[0091] The light ray configuration structure includes a light shielding portion 512 and a first type of barrier wall 410. The light shielding portion 512 is located on the upper side of the first type of pixel P1 to shield the incident light from entering the first light sensing region P11. The first type of barrier wall 410 is located between the first type of pixel P1 and the second type of pixel P2 in response to different types of light signals, to shield the derived light of the second type of pixel P2 from entering the first type of pixel P1 in response to different types of light signals.

[0092] In this application, the light ray configuration structure further includes a second type of barrier wall 420, which is located between the first type of pixel P1 and the second type of pixel P2 in response to the same type of light signal, to reduce the derived light of the second type of pixel P2 from entering the first type of pixel P1 in response to the same type of light signal.

[0093] The following describes each execution step and the structure obtained in the execution step:

[0094] As shown in FIG. 4B, the substrate 440a is etched and a patterned trench is formed, including a first trench 401 corresponding to the first type of barrier wall 410, a second trench 402 corresponding to the second type of barrier wall 420, and a third trench 403 corresponding to the channel isolation structure 430. Figure 7b

[0095] Figure 7c ​​​As shown, a channel isolation structure 430 is fabricated within the third trench 403. For example, an isolation material can be applied to the entire surface of the substrate 440a, and the isolation material can be polished to retain the isolation material within the third trench 403, forming the channel isolation structure 430 (BDTI). Meanwhile, the isolation material within the first trench 401 and the second trench 402 is etched away, exposing the first trench 401 and the second trench 402. The isolation material includes, but is not limited to, silicon oxide, and can also be a high dielectric constant material.

[0096] like Figures 7d-7e As shown, a dielectric layer 501 covering the entire surface of the substrate 440a can be grown by thermal oxidation on the trench surface, or it can be filled with a dielectric layer and then the dielectric layer 501 in the first trench 401 and the second trench 402 is etched, retaining the dielectric layer 501 on the inner walls of the first trench 401 and the second trench 402 and on the surface of the substrate 440a. The dielectric layer 501 can be an oxide.

[0097] like Figures 7f-7g As shown, a light-blocking material covers an entire surface of a substrate 440a. The light-blocking material is etched to form a metal grille 511, a light-blocking portion 512, a second type of barrier wall 420, and a first type of barrier wall 410. The metal grille 511, the light-blocking portion 512, the second type of barrier wall 420, and the first type of barrier wall 410 all use the same light-blocking material, thereby simplifying the manufacturing process. The light-blocking material includes at least one of W, Al, Ti, and Ta, and can be a material layer formed from any one of these materials, or a stack of material layers formed from different materials.

[0098] like Figures 7h-7i As shown, a planarization layer 502 covers the entire surface of the substrate 440a, filling the space between the light-shielding portion 512 and the metal grid 511, thereby planarizing the light-shielding portion 512 and the metal grid 511. The planarization layer 502 can be an oxide. Then, a color filter 520 and a microlens 530 are sequentially fabricated on the planarization layer 502. The color filter 520 can be fabricated using existing color filter fabrication processes, and the microlens 530 can be fabricated using existing microlens processes.

[0099] Figures 8a-8d This is a second schematic cross-sectional view of the image sensor fabrication process in Embodiment 1 of the present invention. The present invention also provides another method for fabricating the image sensor described above, which is similar to... Figures 7a-7i The preparation methods are basically the same, the difference being:

[0100] like Figures 8a-8bAs shown in FIG. 4A, after covering the medium layer 501 on the substrate 440a, a whole first light-blocking material is covered on the substrate 440a. The first light-blocking material is etched to form the second type of wall 420 and the first type of wall 410, both of which are made of the same light-blocking material. The first light-blocking material includes at least one of TiN, TaN, and polysilicon, and can be a material layer made of any of the above materials or a stack of material layers made of different materials.

[0101] As shown in FIG. 4B, after covering the second light-blocking material on the substrate 440a, the second light-blocking material is etched to form the metal grid 511 and the light-blocking part 512, both of which are made of the same light-blocking material. The second light-blocking material includes at least one of W, Al, Ti, and Ta, and can be a material layer made of any of the above materials or a stack of material layers made of different materials. It should be noted that the first light-blocking material and the second light-blocking material are different materials. Figures 8c-8d

[0102] [Embodiment Two]

[0103] Figure 9 FIG. 4C is a schematic view of a cross-sectional structure of an image sensor in an embodiment two of the present application. As shown in FIG. 4C, the image sensor provided in the embodiment two of the present application is basically the same as the image sensor provided in the embodiment one of the present application, and the difference between them lies in that, in the embodiment two, the light-blocking part 512 and the first type of wall 410 are made of a light-blocking material to prevent light from penetrating through, and the second type of wall 420 is made of a light-reducing material to reduce the penetration rate of light penetrating through the second type of wall 420. The light-reducing material includes but is not limited to polysilicon. Since the second type of wall 420 is made of the light-reducing material, the second type of wall 420 can penetrate through the semiconductor structure layer 400. Of course, the depth of the second type of wall 420 is less than the depth of the first type of wall 410. The penetration amount of the derived light into the first type of pixel P1 can be adjusted by setting the depth of the second type of wall 420 and the light penetration rate of the light-reducing material. Figure 9 Figures 1 to 6

[0104] The light-blocking part 512 and the first type of wall 410 are made of a light-blocking material to prevent light from penetrating through. The second type of wall 420 is made of a light-reducing material to reduce the penetration rate of light penetrating through the second type of wall 420. The light-reducing material includes but is not limited to polysilicon. Since the second type of wall 420 is made of the light-reducing material, the second type of wall 420 can penetrate through the semiconductor structure layer 400. Of course, the depth of the second type of wall 420 is less than the depth of the first type of wall 410. The penetration amount of the derived light into the first type of pixel P1 can be adjusted by setting the depth of the second type of wall 420 and the light penetration rate of the light-reducing material.

[0105] Figures 10a-10e FIG. 4D is a schematic view of a cross-sectional structure of an image sensor in an embodiment two of the present application. As shown in FIG. 4D, the image sensor provided in the embodiment two of the present application is basically the same as the image sensor provided in the embodiment one of the present application, and the difference between them lies in that, in the embodiment two, the light-blocking part 512 and the first type of wall 410 are made of a light-blocking material to prevent light from penetrating through, and the second type of wall 420 is made of a light-reducing material to reduce the penetration rate of light penetrating through the second type of wall 420. The light-reducing material includes but is not limited to polysilicon. Since the second type of wall 420 is made of the light-reducing material, the second type of wall 420 can penetrate through the semiconductor structure layer 400. Of course, the depth of the second type of wall 420 is less than the depth of the first type of wall 410. The penetration amount of the derived light into the first type of pixel P1 can be adjusted by setting the depth of the second type of wall 420 and the light penetration rate of the light-reducing material. Figures 10a-10e Figures 7a to 7i

[0106] Figures 10a-10c ​​​​​​As shown, after covering the substrate 440a with a dielectric layer 501, an anti-reflection material is applied to the entire surface of the substrate 440a. The anti-reflection material is then etched to form a second type of barrier 420, wherein the second type of barrier 420 uses an anti-reflection material capable of reducing light transmission.

[0107] like Figures 10d-10e As shown, a light-blocking material covers an entire surface of the substrate 440a. The light-blocking material is etched to form a metal grille 511, a light-shielding portion 512, and a first-type barrier wall 410. The metal grille 511, the light-shielding portion 512, and the first-type barrier wall 410 all use the same light-blocking material. The light-blocking material includes at least one of W, Al, Ti, and Ta, and can be a material layer formed from any one of these materials, or a stack of material layers formed from different materials.

[0108] Those skilled in the art should understand that the remaining structures and working principles of this embodiment are the same as those of Embodiment 1, and will not be repeated here.

[0109] [Example 3]

[0110] Figure 11 This is a schematic diagram of the cross-sectional structure of the image sensor in Embodiment 3 of the present invention. Figure 11 As shown, the image sensor and preparation method provided in Embodiment 3 of the present invention are similar to those in Embodiment 1. Figures 1 to 8d The image sensor and manufacturing method are basically the same in this embodiment, except that:

[0111] In the first type of pixel P1 and the second type of pixel P2, which are adjacent and respond to different types of light signals, the side of the first type of pixel P1 closest to the second type of pixel P2 is covered with a color filter 520 of the same color as the second type of pixel P2. That is, a portion of the color filter 520 covering the upper side of the second type of pixel P2 extends into the area of ​​the first type of pixel P1 that is adjacent and responds to different types of light signals. Since not all light rays are perpendicular to the image sensor, but some are obliquely incident on the image sensor, and the color filter 520 has a certain thickness, extending a portion of the color filter 520 covering the upper side of the second type of pixel P2 into the area of ​​the first type of pixel P1 that is adjacent and responds to different types of light signals can prevent crosstalk between the different types of light signals and the second type of pixel P2. It should be noted that, in the case where the color filter 520 is only set in the area corresponding to the second type pixel P2, the solution of this embodiment can be understood as the color filter 520 of the second type pixel P2 that responds to different types of signals can also extend to the adjacent first type pixel P1 that does not have a color filter 520. It can be understood as an extension of the adjacent pixel color filter 520 rather than the first type pixel P1 itself having a color filter 520.

[0112] SeeFigures 12-14 As shown in the further embodiment, the color filter 520 of the second type of pixel P2 extends to the center of the first type of pixel P1 which responds to different types of light signals. As Figure 12 As shown, the corresponding Figure 4 As shown in the example, for the blue pixel B, two colors of color filters 520 are arranged on the corresponding first type of pixel P1, one is a blue color filter which receives the same color signal, and the other is the color filter 520 of the adjacent green pixel, both of which extend to the center of the first type of pixel P1 and are symmetrically arranged; in addition, for the green pixel G, three colors of color filters 520 are arranged on the corresponding first type of pixel P1, one is a green color filter which receives the same color signal, and the other is the color filter 520 of the adjacent blue pixel and the color filter 520 of the adjacent red pixel, all of which extend to the center of the first type of pixel P1, wherein the blue color filter and the red color filter are symmetrically arranged and the whole of the blue color filter and the red color filter is symmetrically arranged with the green color filter. Similarly, as Figure 13 As shown, the corresponding Figure 5 As shown in the example, the first type of pixel P1 corresponds to three colors but can be understood as four types of uniformly arranged color filters 520 extending to the center. Similarly, as Figure 14 As shown, the corresponding Figure 6 As shown in the example, the first type of pixel P1 has a color filter 520 similar to that designed in Figure 12 Based on the above design, it is beneficial to realize the photosensitive function of the second type of pixel P2 itself while reducing crosstalk.

[0113] Those skilled in the art should understand that the remaining structure and working principle of the embodiment are the same as those of Embodiment One, which will not be repeated here.

[0114] [Embodiment Four]

[0115] Figure 15 is a schematic diagram of the cross-sectional structure of the image sensor in Embodiment Four of the present application. As Figure 15 As shown, the image sensor and the preparation method provided in Embodiment Four of the present application are basically the same as those in Embodiment One Figures 1 to 8d ), the difference is that in the present embodiment:

[0116] The pixel structure further comprises an auxiliary light distribution structure 320, which is prepared based on the same process as the interconnection wiring structure (circuit connection layer 300). Since the circuit connection layer 300 has a metal layer, the metal layer has a certain light reflection effect, so that the reflected modulated light can enter the first type of pixel P1. The area of the auxiliary light distribution structure 320 can be adjusted according to the amount of light entering the first type of pixel P1. The auxiliary light distribution structure 320 and the interconnection wiring structure are prepared based on the same process, which can simplify the preparation process of the image sensor.

[0117] The auxiliary light distribution structure 320 is arranged on the side of the second type of pixel P2 away from the incident light, the incident light passing through the second type of pixel P2 is modulated into the first type of pixel P1 through the auxiliary light distribution structure 320 to obtain modulated light, and the first type of pixel P1 obtains the first signal based on the modulated light and the derived light.

[0118] Those skilled in the art should understand that the remaining structure and working principle of the embodiment are the same as those of the first embodiment, and will not be repeated here.

[0119] [Embodiment five]

[0120] Figure 16 is a schematic diagram of the cross-sectional structure of the image sensor in the fifth embodiment of the present application. As shown in the figure, Figure 16 the image sensor and the preparation method provided in the fifth embodiment of the present application are basically the same as those in the fourth embodiment (the image sensor and the preparation method in the fourth embodiment), Figure 15 the difference is that in the present embodiment:

[0121] The auxiliary light distribution structure 320 comprises a plurality of auxiliary light distribution sub-structures, and the light distribution structure comprises a second type of barrier wall 420, wherein in the direction away from the second type of barrier wall 420, each auxiliary light distribution sub-structure is staggered and arranged away from the second light-sensitive area P21 of the corresponding second type of pixel P2 in turn. For example, the auxiliary light distribution structure 320 comprises a first auxiliary light distribution sub-structure 321 and a second auxiliary light distribution sub-structure 322, and in the direction away from the second type of barrier wall 420, the first auxiliary light distribution sub-structure 321 and the second auxiliary light distribution sub-structure 322 are staggered and arranged away from the second light-sensitive area P21 of the corresponding second type of pixel P2 in turn, so that the auxiliary light distribution structure 320 can provide more modulated light for the first type of pixel P1.

[0122] Those skilled in the art should understand that the remaining structure and working principle of the embodiment are the same as those of the fourth embodiment, and will not be repeated here.

[0123] [Embodiment six]

[0124] Figure 17 is a schematic diagram of the cross-sectional structure of the image sensor in the sixth embodiment of the present application. As shown in the figure,Figure 17 As shown, the image sensor provided by the sixth embodiment of the present application, the preparation method and the image sensor, the preparation method in the first embodiment are basically the same, the difference is that, in the present embodiment: Figures 1 to 8d

[0125] The second type of retaining wall 420 includes a plurality of retaining walls, and the light transmission gap 421 is arranged between adjacent two retaining walls. By using the segmented retaining wall for the second type of retaining wall 420, the proportion of the light transmission gap 421 on the second type of retaining wall 420 can be adjusted, so as to adjust the amount of light entering the first type of pixel P1. The existing process can be used to form the light transmission gap 421. The light transmission gap 421 can be an air cavity or filled with other materials, so as to adjust the light.

[0126] Those skilled in the art should understand that the remaining structure and working principle of the present embodiment are the same as those of the first embodiment, and will not be repeated here.

[0127] The present application also provides an imaging method based on the pixel structure obtained by any one of the first to sixth embodiments. In the imaging method, the first type of pixel P1 has a first exposure time, the second type of pixel P2 has a second exposure time, and the first exposure time is greater than the second exposure time.

[0128] In an example, the second exposure time is greater than 1 / 100 of the first exposure time, for example, the second exposure time is 1 / 50, 1 / 20, 1 / 10 or 1 / 2 of the first exposure time.

[0129] ​For example, the first type of pixel P1 can be controlled to have a longer exposure time than the second type of pixel P2, and the first type of pixel P1 is covered with a light-blocking material (light-blocking part, not transparent to light) so that the light incident above the pixel cannot enter the first type of pixel P1, but the light incident into the adjacent second type of pixel P2 in response to the same type of light signal can enter the first type of pixel P1 due to the diffraction of light. Due to the weak diffraction effect between pixels, a weak light response can be achieved, long exposure can be achieved without easy overexposure, and the dynamic range of the image sensor can be improved. In addition, for light sources with varying brightness over time, such as light sources (e.g., LEDs) working in pulse modulation mode, the design of the present application can be based on long exposure of the first type of pixel P1, and can be suitable for photographing photos or videos with flickering light sources, and can attenuate the influence of light source flicker. Further, each second type of pixel P2 corresponding to the first type of pixel P1 responds to the same type of light signal, so the spectral curve of these pixels is consistent with the adjacent second type of pixel P2, and these pixels can have appropriate spectral response through appropriate settings; in addition, based on the design of the present application, the second type of pixel P2 responding to different types of signals can be arranged around the first type of pixel P1. The first exposure time and the second exposure time can be based on existing designs.

[0130] The present application also provides an electronic device, wherein the electronic device comprises the pixel structure of the image sensor according to any one of the above embodiments. The electronic device can be a security camera, a car electronic camera, a mobile phone camera, a drone, a machine vision, and a conventional camera, etc. Further, the electronic device can use the imaging method of embodiment four for imaging.

[0131] In summary, the first type of pixel P1 with the light shielding part on the top and the second type of pixel P2 without the light shielding part on the top and capable of receiving light are designed, the derived light of the second type of pixel P2 is used as the response light of the first type of pixel P1, and each second type of pixel P2 corresponding to the first type of pixel P1 responds to the same type of light signal, so that the first type of pixel P1 receives the same type of derived light to generate the first signal, meanwhile, the second type of pixel P2 generates the second signal based on the incident light, and the second type of pixel P2 responding to different types of signals can be arranged around the first type of pixel P1, so that the effective image signal can be obtained based on the first signal of the first type of pixel P1 and the second signal of the second type of pixel P2, the dynamic range of the image is improved, and the acquisition of the photo or video with light source flicker can be effectively realized based on the above signals. In addition, based on the design of the application, the light shielding part 512 and the first type of barrier wall 410 and the second type of barrier wall 42 can be simultaneously prepared, the modulation of the light signals of the first type of pixel P1 and the second type of pixel P2 can be realized, and the crosstalk between different types of light signals can be effectively prevented, the preparation process can be simplified, and the efficiency can be improved. Therefore, the application effectively overcomes the various shortcomings in the prior art and has high industrial utilization value.

[0132] In this document, the above, below, left, right, front, back and other orientation words are defined with the structure in the figure and the position of the structure relative to each other in the figure, just to express the technical solution clearly and conveniently. It should be understood that the use of the orientation words should not limit the scope of the application claimed. It should also be understood that the terms "first" and "second" used herein are only used for name distinction and do not limit the number and order.

[0133] The above is only the preferred embodiment of the present application, and does not limit the present application in any form. Although the present application has been disclosed as above with the preferred embodiment, it is not intended to limit the present application. Any skilled person in the art can make some changes or modifications to the above disclosed technical content without departing from the scope of the technical solution of the present application, and the equivalent embodiments of equivalent changes are obtained. Any simple modification, equivalent change and modification of the above embodiments made according to the technical essence of the present application are still within the protection scope of the technical solution of the present application.

Claims

1. An image sensor, characterized by, The image sensor comprises: a first type of pixel comprising a first light sensing region; a second type of pixel comprising a second light sensing region, and the first type of pixel and the second type of pixel are spaced apart from each other; a light configuration structure comprising a light shielding part and a first type of barrier wall; the light shielding part is located on the upper side of the first type of pixel to shield incident light from entering the first light sensing region; the upper end of the first type of barrier wall is connected with the light shielding part, and the other end penetrates through the semiconductor structure layer; the first type of barrier wall is located between the first type of pixel and the second type of pixel in response to different types of light signals to shield the derived light of the second type of pixel from entering the first type of pixel in response to different types of light signals; wherein, based on the light configuration structure, the incident light enters the region corresponding to the second type of pixel and generates derived light, the derived light enters the first type of pixel adjacent to the second type of pixel in response to the same type of light signal, the first light sensing region receives the derived light to generate a first signal, and the second light sensing region receives the incident light to generate a second signal.

2. The image sensor of claim 1, wherein, The light configuration structure further comprises a second type of barrier wall located between the first type of pixel and the second type of pixel in response to the same type of light signal to reduce the derived light of the second type of pixel from entering the first type of pixel in response to the same type of light signal.

3. The image sensor of claim 2, wherein, The depth of the second type of barrier wall is less than the depth of the first type of barrier wall; and / or, the second type of barrier wall comprises a plurality of barrier walls, and adjacent two barrier walls have a light transmission gap therebetween.

4. The image sensor of claim 2, wherein, The light shielding part, the second type of barrier wall and the first type of barrier wall all adopt a light blocking material to prevent light transmission; or, the light shielding part and the first type of barrier wall adopt a light blocking material to prevent light transmission, and the second type of barrier wall adopts a light reduction material to reduce the light transmission rate through the second type of barrier wall.

5. The image sensor of claim 4, wherein, When the light shielding part, the second type of barrier wall and the first type of barrier wall all adopt a light blocking material, the light shielding part, the second type of barrier wall and the first type of barrier wall are made of the same material; or, the second type of barrier wall and the first type of barrier wall are made of the same material and different from the material of the light shielding part.

6. The image sensor of claim 1, wherein, The light shielding rate of the light configuration structure is greater than or equal to 98%; and / or, the first type of pixel and the second type of pixel have the same shape and size and are periodically arrayed, or the first light sensing region area of the first type of pixel is smaller than the second light sensing region area of the second type of pixel.

7. The image sensor of claim 1, wherein, The image sensor comprises a metal grid, and the light shielding part is arranged in the same layer as the metal grid; and / or, the image sensor comprises a color filter and a flat layer filled at least between the light shielding parts, and the color filter is covered on the flat layer.

8. The image sensor of claim 1, wherein, The image sensor comprises a color filter, and the first type of pixels and the second type of pixels adjacent to each other are covered with the same color of the color filter, so that each first type of pixel and the corresponding second type of pixel respond to the same type of light signal; or the color filter is only arranged in the area corresponding to the second type of pixel and / or the microlens is only arranged in the area corresponding to the second type of pixel.

9. The image sensor of claim 8, wherein, In the first type of pixels and the second type of pixels adjacent to each other and responding to different types of light signals, the first type of pixels are covered with the color filter of the same color as the second type of pixels on one side close to the second type of pixels.

10. The image sensor of claim 9, wherein, The color filter of the second type of pixels extends to the center of the first type of pixels responding to different types of light signals.

11. The image sensor of claim 1, wherein, The image sensor comprises a plurality of pixel units, each of which comprises a first color pixel subunit, a second color pixel subunit and a third color pixel subunit, wherein the pixel subunit of at least one color comprises at least one first type of pixel and at least one second type of pixel.

12. The image sensor according to any one of claims 1 to 11, wherein The image sensor further comprises an auxiliary light distribution structure arranged on the side of the second type of pixel away from the incident light, wherein the incident light passing through the second type of pixel is modulated into modulated light by the auxiliary light distribution structure and enters the first type of pixel, and the first type of pixel obtains the first signal based on the modulated light and the derived light.

13. The image sensor of claim 12, wherein, The auxiliary light distribution structure comprises a plurality of auxiliary light distribution substructures, and the light ray configuration structure comprises a second type of barrier wall, wherein in the direction away from the second type of barrier wall, each auxiliary light distribution substructure is staggered with each other and sequentially away from the second light sensing area of the corresponding second type of pixel.

14. An electronic device, comprising: An image sensor as claimed in any one of claims 1-13.

15. A method of manufacturing an image sensor as claimed in any one of claims 1-13, characterized in that The preparation method comprises the following steps: providing a substrate, and preparing the first type of pixels and the second type of pixels in the substrate; preparing the light ray configuration structure on the substrate, the light ray configuration structure comprising a light shielding part and a first type of barrier wall, the light shielding part being located on the upper side of the first type of pixel to shield the incident light from entering the first light sensing area; the first type of barrier wall being located between the first type of pixel responding to different types of light signals and the second type of pixel to shield the derived light of the second type of pixel from entering the first type of pixel responding to different types of light signals.

16. The method of fabricating an image sensor according to claim 15, wherein The image sensor comprises a metal grid, and the light shielding part and the metal grid are made of the same material and prepared by the same process. And / or, the image sensor further comprises an auxiliary light distribution structure, and the auxiliary light distribution structure and the interconnection wiring structure are prepared based on the same process.

17. An imaging method based on the image sensor according to any one of claims 1 to 13, characterized by, The imaging method comprises the following steps: controlling the first type of pixels to have a first exposure time, the second type of pixels to have a second exposure time, and the first exposure time to be greater than the second exposure time.

Images