Photoelectric sensor and forming method thereof

Abstract

The invention discloses a photoelectric sensor and a forming method thereof, and the photoelectric sensor comprises a substrate which is provided with a light receiving surface, the substrate comprises a photosensitive pixel region, the photosensitive pixel region comprises a plurality of pixel unit regions which are distributed in a matrix, and each pixel unit region is divided into a plurality of sub-unit regions which are distributed in an array; the light insulation structure penetrates through the part of thickness of the substrate on one side of the light receiving surface, and the light insulation structure is located between the adjacent pixel unit areas and in the substrate between the adjacent subunit areas; and the light splitting structures penetrate through a part of thickness of the substrate on one side of the light receiving surface, the light splitting structures are distributed in each subunit area in a one-to-one correspondence manner, and an acute included angle is formed between the extension direction of each light splitting structure and the row direction or the column direction of the array arrangement. The focusing performance of the photoelectric sensor can be improved.

Description

Technical Field

[0001] Embodiments of the present invention relate to the field of semiconductor manufacturing, and in particular, to an optoelectronic sensor and a method for forming the same. Background Art

[0002] An optoelectronic sensor is a device that converts an optical signal into an electrical signal. Its working principle is based on the photoelectric effect, which refers to the phenomenon that when light irradiates on certain substances, the electrons of the substances absorb the energy of photons and generate corresponding electrical effects.

[0003] For example, CCD (Charge Coupled Device) image sensors and CMOS image sensors (CMOS Image Senser, CIS) use the photoelectric conversion function to convert an optical image into an electrical signal and then output a digital image, and are currently widely used in digital cameras and other electro-optical devices. ToF (Time of Flight) distance sensors project a modulated infrared light source onto an object, person, or scene, and then the reflected light is captured by the ToF sensor. The sensor measures the light intensity and phase difference received by each pixel, thereby obtaining a highly reliable depth image and a grayscale image of the entire scene. This technology can be used in various ranging scenarios such as autonomous driving, floor-sweeping robots, VR (Virtual Reality) / AR (Augmented Reality) modeling, etc. Summary of the Invention

[0004] The problem solved by the embodiments of the present invention is to provide an optoelectronic sensor and a method for forming the same, so as to improve the focusing performance of the optoelectronic sensor.

[0005] To solve the above problem, an optoelectronic sensor provided by an embodiment of the present invention includes: a substrate having a light-receiving surface, and the substrate includes a photosensitive pixel region, the photosensitive pixel region includes a plurality of pixel unit regions arranged in a matrix, and each pixel unit region is divided into a plurality of sub-unit regions arranged in an array; a light isolation structure penetrating through a partial thickness of the substrate on one side of the light-receiving surface, and the light isolation structure is located in the substrate between adjacent pixel unit regions and between adjacent sub-unit regions; a light splitting structure penetrating through a partial thickness of the substrate on one side of the light-receiving surface, and the light splitting structures are respectively distributed in each sub-unit region, and the extending direction of each light splitting structure forms an acute angle with the row direction or the column direction of the array arrangement.

[0006] Optionally, each pixel unit region has four sub-unit regions arranged in an array, and the light isolation structures between the four sub-unit regions intersect vertically; the extending direction of each light splitting structure forms an acute angle with the extending direction of the light isolation structure inside the pixel unit region.

[0007] Optionally, in each pixel unit region, the extending direction of the light splitting structure passes through the intersection point of the light shielding structures inside the pixel unit region.

[0008] Optionally, the pixel unit region has a preset light receiving region located at the intersection point of the light shielding structures inside it, and covering a partial area of the four sub-unit regions near the intersection point; in each pixel unit region, the light splitting structure extends into the light receiving region.

[0009] Optionally, in each pixel unit region, the intersection point of the light shielding structures inside it is the center point of the pixel unit region.

[0010] Optionally, the morphology of the light splitting structure is strip-shaped.

[0011] Optionally, the length of the light splitting structure is from 200 nm to 600 nm; the width of the light splitting structure is from 100 nm to 300 nm.

[0012] Optionally, the included angle between the extending direction of the light splitting structure and the row direction or column direction of the array arrangement is from 30° to 60°.

[0013] Optionally, the included angle between the extending direction of the light splitting structure and the row direction or column direction of the array arrangement is 45°.

[0014] Optionally, the light splitting structure and the light shielding structure are made of the same material.

[0015] An embodiment of the present invention further provides a method for forming a photoelectric sensor, including: providing a substrate, the substrate having a light receiving surface, and the substrate including a photosensitive pixel region, the photosensitive pixel region including a plurality of pixel unit regions distributed in a matrix; forming a light-transmitting layer on the light receiving surface, the light-transmitting layer including a plurality of lens layers corresponding to the pixel unit regions one by one, the lens layer covering the light receiving surface of the pixel unit region, and the lens layer being used for concentrating light in the pixel unit region.

[0016] Optionally, in the step of providing the substrate, each pixel unit region has four sub-unit regions arranged in an array, and the intersection lines between the four sub-unit regions intersect perpendicularly; in the step of forming the light splitting structure penetrating through a partial thickness of the substrate on one side of the light receiving surface, the extending direction of each light splitting structure has an acute included angle with the extending direction of the intersection line.

[0017] Optionally, in the step of forming the light splitting structure penetrating through a partial thickness of the substrate on one side of the light receiving surface, in each pixel unit region, the extending direction of the light splitting structure passes through the intersection point of the intersection lines.

[0018] Optionally, in the step of providing the substrate, the pixel unit region has a preset light receiving region located at the intersection point of the intersection lines, and covering a partial area of the four sub-unit regions near the intersection point; in the step of forming the light splitting structure penetrating through a partial thickness of the substrate on one side of the light receiving surface, in each pixel unit region, the light splitting structure extends into the light receiving region.

[0019] Optionally, in the step of providing the substrate, in each pixel unit region, the intersection point of the boundary lines is the center point of the pixel unit region.

[0020] Optionally, in the step of forming the light splitting structure of the substrate with a partial thickness penetrating one side of the light receiving surface, the morphology of the light splitting structure is strip-shaped.

[0021] Optionally, in the step of forming the light splitting structure of the substrate with a partial thickness penetrating one side of the light receiving surface, the included angle between the extending direction of the light splitting structure and the row direction or column direction of the array arrangement is 30° to 60°.

[0022] Optionally, in the step of forming the light splitting structure of the substrate with a partial thickness penetrating one side of the light receiving surface, the included angle between the extending direction of the light splitting structure and the row direction or column direction of the array arrangement is 45°.

[0023] Optionally, the step of forming the light blocking structure of the substrate with a partial thickness penetrating one side of the light receiving surface includes: patterning the substrate to form first grooves in the substrate located between adjacent pixel unit regions and between adjacent sub-unit regions; filling the first grooves to form the light blocking structure; the step of forming the light splitting structure of the substrate with a partial thickness penetrating one side of the light receiving surface includes: patterning the substrate to form second grooves in the substrate distributed in each sub-unit region; filling the second grooves to form the light splitting structure.

[0024] Optionally, in the same step, the first grooves and the second grooves are filled.

[0025] Compared with the prior art, the technical solution of the embodiment of the present invention has the following advantages:

[0026] In the photoelectric sensor provided by the embodiment of the present invention, the light splitting structures are distributed one-to-one in each sub-unit region, and the extending direction of each light splitting structure has an acute included angle with the row direction or column direction of the array arrangement; in the embodiment of the present invention, each pixel unit region is divided into a plurality of sub-unit regions arranged in an array, and the plurality of sub-unit regions are simultaneously photosensitive when the pixel unit region receives light, and subsequent alignment is performed on the plurality of sub-unit regions to achieve the focusing of the pixel unit region. Then, when each pixel unit region receives light, when the light spot is relatively concentrated at the junction of the plurality of sub-unit regions, the light splitting effect is achieved, so that the light can be better dispersed into the corresponding sub-unit regions, which is beneficial to increasing the effective photosensitive area of each sub-unit region, beneficial to making the photosensitivity of each sub-unit region more uniform, correspondingly, beneficial to reducing the photosensitivity non-uniformity between the plurality of sub-unit regions, thereby beneficial to making the focusing of the pixel unit region more accurate, and further beneficial to improving the focusing performance of the photoelectric sensor.

[0027] In the method for forming a photoelectric sensor provided by an embodiment of the present invention, a light splitting structure of a substrate with a partial thickness penetrating one side of the light receiving surface is formed. The light splitting structures are distributed in each sub-unit area in a one-to-one correspondence, and the extending direction of each light splitting structure has an acute angle with the row direction or the column direction of the array arrangement. In the embodiment of the present invention, each pixel unit area is divided into a plurality of sub-unit areas arranged in an array. When the pixel unit area receives light, the plurality of sub-unit areas sense light simultaneously, and subsequent alignment of the plurality of sub-unit areas is performed to achieve focusing of the pixel unit area. Then, when each pixel unit area receives light, when the light spot is relatively concentrated at the junction of the plurality of sub-unit areas, a light splitting effect is achieved, enabling the light to be better dispersed into the corresponding sub-unit areas, which is beneficial to increasing the effective light-sensing area of each sub-unit area, making the light sensing of each sub-unit area more uniform. Correspondingly, it is beneficial to reduce the non-uniformity of light sensing between the plurality of sub-unit areas, thereby facilitating more accurate focusing of the pixel unit area, and further improving the focusing performance of the photoelectric sensor. Description of the Drawings

[0028] Figure 1 and Figure 2 is a schematic structural diagram corresponding to a photoelectric sensor;

[0029] Figures 3 to 6 is a schematic structural diagram corresponding to an embodiment of the photoelectric sensor of the present invention;

[0030] Figures 7 to 11 is a schematic structural diagram corresponding to each step in an embodiment of the method for forming the photoelectric sensor of the present invention. Detailed Embodiments

[0031] As can be seen from the background art, the current focusing performance of photoelectric sensors is relatively low. Now, in combination with a photoelectric sensor, the reasons for its low focusing performance are analyzed.

[0032] Figure 1 and Figure 2 is a schematic structural diagram corresponding to a photoelectric sensor.

[0033] With reference to Figure 1 and Figure 2 , the photoelectric sensor includes: a substrate 10 having a light receiving surface 11, and the substrate 10 includes a photosensitive pixel area. The photosensitive pixel area includes a plurality of pixel unit areas 10a arranged in a matrix, and each pixel unit area 10a is divided into four sub-unit areas 10b arranged in an array; a light isolation structure 20 penetrating a partial thickness of the substrate 10 on one side of the light receiving surface 11, and the light isolation structure 20 is located in the substrate 10 between adjacent pixel unit areas 10a and between adjacent sub-unit areas 10b.

[0034] Each pixel unit area 10a is divided into four sub-unit areas 10b arranged in an array. When the pixel unit area 10a receives light, the four sub-unit areas sense light simultaneously when the pixel unit area receives light, which is four-phase (Quad Phase Detection, QPD) focusing. Each pixel unit area 10a has a lens, and each sub-unit area 10b corresponds to a photodiode under each lens. That is, a total of four photodiodes sense light simultaneously and output electrical signals with phases. Subsequently, the four sub-unit areas 10b are combined in pairs, and their phase differences are compared with a reference value to achieve phase focusing. Correspondingly, the position of the light spot 10c caused by the light concentration of the lens is located at the center point of the pixel unit area 10a, which is the point where the four sub-unit areas 10c meet. Then, for each sub-unit area 10a, light sensing is performed within a certain angular range, resulting in light sensing saturation in the light sensing angle of each sub-unit area 10a, and no light sensing in other areas, thus leading to uneven light sensing within each sub-unit area 10a. Moreover, during the working process, when the light spot 10c fluctuates, the light incident amount of the light spot 10c in each sub-unit area 10b varies greatly, resulting in poor light sensing uniformity of the four sub-unit areas 10b, thereby leading to inaccurate focusing of the pixel unit area 10a and further poor focusing performance of the photoelectric sensor.

[0035] To solve the above technical problems, an embodiment of the present invention provides a photoelectric sensor, including: a substrate having a light-receiving surface, and the substrate includes a photosensitive pixel area, and the photosensitive pixel area includes a plurality of pixel unit areas arranged in a matrix, and each pixel unit area is divided into a plurality of sub-unit areas arranged in an array; a light-blocking structure penetrating through a partial thickness of the substrate on one side of the light-receiving surface, and the light-blocking structure is located in the substrate between adjacent pixel unit areas and between adjacent sub-unit areas; a light-splitting structure penetrating through a partial thickness of the substrate on one side of the light-receiving surface, and the light-splitting structures are respectively distributed in each sub-unit area, and the extending direction of each light-splitting structure has an acute angle with the row direction or the column direction of the array arrangement.

[0036] In an embodiment of the present invention, each pixel unit area is divided into a plurality of sub-unit areas arranged in an array. The plurality of sub-unit areas sense light simultaneously when the pixel unit area receives light, and alignment is performed on the plurality of sub-unit areas subsequently to achieve focusing of the pixel unit area. Then, when the pixel unit area receives light, when the light spot is relatively concentrated at the junction of the plurality of sub-unit areas, a light-splitting effect is achieved, enabling the light to be better dispersed into the corresponding sub-unit areas, which is beneficial to increasing the effective light-sensing area of each sub-unit area, beneficial to making the light sensing of each sub-unit area more uniform. Correspondingly, it is beneficial to reduce the light-sensing non-uniformity between the plurality of sub-unit areas, thereby beneficial to making the focusing of the pixel unit area more accurate, and further beneficial to improving the focusing performance of the photoelectric sensor.

[0037] To make the above objects, features, and advantages of the embodiments of the present invention more obvious and understandable, the following provides a detailed description of specific embodiments of the present invention with reference to the accompanying drawings.

[0038] Reference Figures 3 to 6 , is a schematic structural diagram corresponding to an embodiment of the optoelectronic sensor of the present invention.

[0039] With reference to Figures 3 to 6 , Figure 3 (a) is a top view of the substrate, Figure 3 (b) is Figure 3 a partial enlarged view of any photosensitive pixel region in Figure 4 For Figure 3 (a), a corresponding cross-sectional view, Figure 5 For Figure 4 a partial enlarged view of the dashed box in Figure 6 For Figure 5 a top view of Figure 6 , the optoelectronic sensor includes: a substrate 100 having a light-receiving surface 101, and the substrate 100 includes a photosensitive pixel region P, and the photosensitive pixel region P includes a plurality of pixel unit regions 100a arranged in a matrix, and each pixel unit region 100a is divided into a plurality of sub-unit regions 100b arranged in an array; a light-blocking structure 310 penetrating through a partial thickness of the substrate 100 on one side of the light-receiving surface 101, and the light-blocking structure 310 is located in the substrate 100 between adjacent pixel unit regions 100a and between adjacent sub-unit regions 100b; a light-splitting structure 320 penetrating through a partial thickness of the substrate 100 on one side of the light-receiving surface 101, and the light-splitting structure 320 is correspondingly distributed in each sub-unit region 100b, and the extending direction of each light-splitting structure 320 forms an acute angle with the row direction (such as Figure 6 the X direction shown in Figure 6 ) or the column direction (such as Figure 6 the Y direction shown in

[0040] As an example, in this embodiment, the optoelectronic sensor is taken as a CMOS image sensor (CMOS Image Senser, CIS) for illustration.

[0041] In other embodiments, the optoelectronic sensor may also be a TOF (Time of Flight) sensor, a CCD (Charge Coupled Device) image sensor, or an iTOF (indirect Time of Flight) sensor, etc.

[0042] The substrate 100 is used to provide a process platform for subsequent process manufacturing.

[0043] In this embodiment, the substrate 100 includes a substrate 120 and a first interconnect structure layer 130 located on the substrate 120.

[0044] In this embodiment, the material of the substrate 120 includes silicon, and the substrate 120 is a silicon substrate. In other embodiments, the material of the substrate may also be other materials such as germanium, silicon germanide, silicon carbide, gallium arsenide, or indium gallium, and the substrate may also be other types of substrates such as silicon-on-insulator substrate or germanium-on-insulator substrate.

[0045] In this embodiment, the substrate 100 is a pixel wafer, including a first surface 102 where the first interconnect structure layer 130 is located, and a second surface opposite to the first surface 102.

[0046] In this embodiment, the substrate 100 is a backside illumination (BSI) pixel wafer, and receives light from its second surface.

[0047] Correspondingly, in this embodiment, the photoelectric sensor is a backside illumination photoelectric sensor.

[0048] In other embodiments, the substrate may also be a frontside illumination (FSI) pixel wafer, and receives light from its first surface.

[0049] In this embodiment, only a part of the photosensitive pixel region P and the pixel unit region 100a are shown in the figure. The pixel unit region 100a may also include device structures such as optoelectronic elements (e.g., photodiodes). Among them, the photodiode may be a backside illumination single photon avalanche diode (SPAD). For the purpose of simplification, the detailed structures of the above components are not shown in the embodiments of the present invention.

[0050] In this embodiment, if the substrate 100 is defined as the first substrate 100, the photoelectric sensor further includes: a second substrate (not shown), which is used as a logic wafer and is bonded to the first surface 102 of the first substrate 100.

[0051] The second substrate serves as a logic wafer and is used to analyze and process the electrical signals provided by the pixel wafer.

[0052] By separately arranging the photosensitive pixel region P and the logic region on two wafers and bonding the pixel wafer and the logic wafer together, a larger pixel area can be obtained, which is beneficial to shortening the path of light reaching the optoelectronic element, reducing light scattering, making the light more focused, thereby improving the photosensitive ability of the photoelectric sensor in low-light environments and reducing system noise and crosstalk.

[0053] In this embodiment, the substrate 120 of the first substrate 100 is the first substrate 120, and the second substrate includes a second substrate 220 and a second interconnect structure layer 210 located on the second substrate 220.

[0054] In this embodiment, the material of the second substrate 220 includes silicon, and the second substrate 220 is a silicon substrate. In other embodiments, the material of the second substrate may also be other materials such as germanium, silicon germanide, silicon carbide, gallium arsenide, or indium gallium, and the second substrate may also be other types of substrates such as a silicon-on-insulator substrate or a germanium-on-insulator substrate.

[0055] Correspondingly, in this embodiment, logic transistors (not shown in the figure) are also formed in the second substrate, and the logic transistors are used to perform logic processing on the electrical signals provided by the pixel wafer. Specifically, the logic transistors may include a logic gate structure located on the second substrate, and a logic drain region and a logic source region in the second substrate on both sides of the logic gate structure, respectively.

[0056] As an embodiment, the bonding between the first substrate 100 and the second substrate is achieved by means of hybrid bonding.

[0057] Specifically, in this embodiment, the pixel wafer and the logic wafer can be bonded together by using dielectric bonding, and then the electrical connection between the first interconnect structure layer 130 and the second interconnect structure layer 210 is performed.

[0058] Among them, the first interconnect structure layer 130 may be a first metal wire, or the first interconnect structure layer 130 is a first through-silicon via interconnect structure (TSV), or the first interconnect structure layer 130 includes a first via interconnect structure and a first metal wire located on the first via interconnect structure; the second interconnect structure layer 210 may be a second metal wire, or the second interconnect structure layer 210 is a second through-silicon via interconnect structure (TSV), or the second interconnect structure layer 210 includes a second via interconnect structure and a second metal wire located on the second via interconnect structure.

[0059] It should be noted that the above method for realizing the bonding between the first substrate 100 and the second substrate is only taken as an embodiment, and the bonding method between the first substrate 100 and the second substrate is not limited to this. For example: In other embodiments, the bonding method between the first substrate and the second substrate may also be direct bonding (such as fusion bonding and anodic bonding) or indirect bonding techniques (such as metal eutectic, thermocompression bonding, and adhesive bonding), etc.

[0060] In this embodiment, the substrate 100 has a light-receiving surface 101. Among them, the light-receiving surface 101 refers to the surface for receiving light.

[0061] The photosensitive pixel region P is used to receive optical signals so as to convert the optical signals into electrical signals.

[0062] In the substrate 100, the number of photosensitive pixel regions P is multiple, and the multiple photosensitive pixel regions P are arranged in a matrix. The pixel unit region 100a is used to form pixels, and the sub-unit regions 100b of each pixel unit region 100a are used to receive optical signals simultaneously.

[0063] In this embodiment, each pixel unit region 100a has four sub-unit regions 100b arranged in an array.

[0064] In this embodiment, each pixel unit region 100a is divided into multiple sub-unit regions 100b arranged in an array. When the pixel unit region 100a is exposed to light, the four sub-unit regions 100b are simultaneously photosensitive when the pixel unit region 100a is exposed to light, which is four-phase (Quad Phase Detection, QPD) focusing. Each pixel unit region 100a has a lens, and each sub-unit region 100b corresponds to a photodiode under each lens, that is, a total of four photodiodes are simultaneously photosensitive and output electrical signals with phases. Subsequently, the four sub-unit regions 100b are combined in pairs, and their phase differences are compared with a reference value to achieve phase focusing.

[0065] The light isolation structure 310 is used to prevent optical crosstalk between adjacent pixels and is also used to divide adjacent sub-unit regions 100b.

[0066] Specifically, the light isolation structure 310 has an occlusion effect on light. The light isolation structure 310 is located between the light-transmitting layers of adjacent pixel unit regions 100a. When incident light irradiates the photosensitive pixel region P, the incident light will only enter the corresponding pixel unit region 100a through the light-transmitting layer and cannot pass through the light isolation structure 310 around the light-transmitting layer to enter adjacent other pixel unit regions 100a, avoiding optical crosstalk to other pixel unit regions 100a.

[0067] In this embodiment, the material of the light isolation structure 310 is a conductive material. Conductive materials are usually light-impermeable, thus meeting the function of the light isolation structure 310 for light isolation.

[0068] As an example, the conductive material can be a metal material. Specifically, the material of the light isolation structure 310 includes one or more of W, Al, Cu, Ti, TiN, Ta, and TaN. In this embodiment, the material of the light isolation structure 310 is W.

[0069] In other embodiments, the conductive material can also be polysilicon doped with conductive ions.

[0070] In this embodiment, the light isolation structures 310 between the four sub-unit regions 100b intersect vertically.

[0071] Correspondingly, the light shielding structure 310 divides the pixel unit area 100a into four sub-unit areas 100b in a "field" - shaped array.

[0072] In this embodiment, the pixel unit area 100a has a preset light - receiving area 100c at the intersection of the light shielding structure 310 inside it, and the preset light - receiving area 100c covers a partial area near the intersection of the four sub - unit areas 100b.

[0073] When the preset light - receiving area 100c is preset to receive light, it is the area of the pixel unit area 100a where light converges on the light - receiving surface 101.

[0074] In this embodiment, in each pixel unit area 100a, the intersection of the light shielding structure 310 inside it is the center point of the pixel unit area 100a.

[0075] Since the intersection of the light shielding structure 310 inside it is the center point of the pixel unit area 100a, the sub - unit areas 100b divided by the light shielding structure 310 are evenly arranged, and the photosensitive areas of the respective sub - unit areas 100b are similar, making the photosensitivity of each sub - unit area 100b more uniform and making the focusing of the pixel unit area 100a more accurate.

[0076] The light splitting structure 320 is used to split the light incident on the sub - unit area 100b. Specifically, the extending direction of each light splitting structure 320 has an acute - angle with the row direction or the column direction of the array arrangement. When light is incident on the sub - unit area 100b, it is reflected by the light splitting structure 320 and dispersed into the corresponding sub - unit area 100b.

[0077] In this embodiment, each pixel unit area 100a is divided into a plurality of sub - unit areas 100b arranged in an array. When the pixel unit area 100a receives light, the plurality of sub - unit areas 100b sense light simultaneously and are aligned in the subsequent process. When the pixel unit area 100a receives light, when the light spot is relatively concentrated at the junction of the plurality of sub - unit areas 100b, the light splitting function is played, enabling the light to be better dispersed into the corresponding sub - unit areas 100b, which is beneficial to increasing the effective photosensitive area of each sub - unit area 100b, making the photosensitivity of each sub - unit area 100b more uniform. Correspondingly, it is beneficial to reduce the photosensitivity non - uniformity between the plurality of sub - unit areas 100b, thereby making the focusing of the pixel unit area 100a more accurate and further improving the focusing performance of the photoelectric sensor.

[0078] In this embodiment, the light shielding structure 310 extends to divide the pixel unit area 100a. Correspondingly, in this embodiment, the extending direction of each light splitting structure 320 has an acute - angle with the extending direction of the light shielding structure 310 inside the pixel unit area 100a.

[0079] In this embodiment, in each pixel unit area 100a, the extending direction of the light splitting structure 320 passes through the intersection points of the light shielding structure 310 inside the pixel unit area 100a.

[0080] If the extending direction of the light splitting structure 320 passes through the intersection points of the light shielding structure 310 inside the pixel unit area 100a, then the light splitting structures 320 in each sub-unit area 100b all point to the center of the preset light receiving area 100c, so that in each word unit area 100b, the light splitting effect of the light splitting structure 320 on the light incident on the preset light receiving area 100c is more uniform.

[0081] In this embodiment, in each pixel unit area 100a, the light splitting structure 320 extends into the light receiving area 100c.

[0082] In each pixel unit area 100a, the light splitting structure 320 extends into the light receiving area 100c, so that the incident light in each sub-unit area 100b can be split.

[0083] In this embodiment, the morphology of the light splitting structure 320 is strip-shaped.

[0084] If the morphology of the light splitting structure 320 is strip-shaped, then when the occupied space of the light splitting structure 320 is as small as possible, it can play a role in splitting as much incident light as possible.

[0085] It should be noted that in this embodiment, the length of the light splitting structure 320 should not be too large or too small. If the length of the light splitting structure 320 is too large, it is easy to cause unnecessary waste and make it difficult to form the light splitting structure 320; if the length of the light splitting structure 320 is too small, it is easy to result in too few areas where the incident light can be split, and the light splitting effect of the light splitting structure 320 on the incident light is insufficient, affecting the light splitting effect of the light splitting structure 320 and making it difficult to achieve the effect of making the photosensitivity of each sub-unit area 100b more uniform. Therefore, in this embodiment, the length of the light splitting structure 320 is 200 nm to 600 nm.

[0086] It should also be noted that in this embodiment, the width of the light splitting structure 320 should not be too large or too small. If the width of the light splitting structure 320 is too large, it is easy to occupy too much space in the sub-unit area 100b and cause unnecessary waste. If the width of the light splitting structure 320 is too small, it is easy to make it difficult to form the light splitting structure 320. Therefore, in this embodiment, the width of the light splitting structure 320 is 100 nm to 300 nm.

[0087] It should also be noted that in this embodiment, the included angle between the extending direction of the light splitting structure 320 and the row direction or column direction of the array arrangement should not be too large or too small. If the included angle between the extending direction of the light splitting structure 320 and the row direction or column direction of the array arrangement is too large or too small, it is easy to cause the extending direction of the light splitting structure 320 to be too close to the row direction or column direction, which will still cause the incident light to be too concentrated, and it is difficult to achieve a good light splitting effect and the effect of making the photosensitivity of each sub-unit area 100b more uniform. Therefore, in this embodiment, the included angle between the extending direction of the light splitting structure 320 and the row direction or column direction of the array arrangement is 30° to 60°.

[0088] Specifically, in this embodiment, the included angle between the extending direction of the light splitting structure 320 and the row direction or column direction of the array arrangement is 45°, which is beneficial to further achieve better dispersion of the incident light into the corresponding sub-unit area 100b, further beneficial to increasing the effective photosensitive area of each sub-unit area 100b, and further beneficial to making the photosensitivity of each sub-unit area 100b more uniform.

[0089] In this embodiment, when forming the light shielding structure 310, the material is filled at the same time to form the light splitting structure 320. Therefore, in this embodiment, the materials of the light splitting structure 320 and the light shielding structure 310 are the same.

[0090] Correspondingly, in this embodiment, the material of the light splitting structure 320 is a conductive material. Conductive materials are usually light-impermeable, so that the light splitting structure 320 can play a role in splitting light.

[0091] As an example, the conductive material can be a metal material. Specifically, the material of the light splitting structure 320 includes one or more of W, Al, Cu, Ti, TiN, Ta, and TaN. In this embodiment, the material of the light splitting structure 320 is W.

[0092] In other embodiments, the conductive material can also be polysilicon doped with conductive ions.

[0093] In this embodiment, the photoelectric sensor further includes: a light-transmitting layer covering the light-receiving surface 101 of the substrate 100 of each sub-unit area 100b.

[0094] The light-transmitting layer has a light-transmitting property. When the light-transmitting layer is formed on the light-receiving surface 101, light can pass through the light-transmitting layer and irradiate on the light-receiving surface 101.

[0095] In this embodiment, the material of the light-transmitting layer is a light-transmitting material, and moreover, the material of the light-transmitting layer is an insulating material to prevent the electrical performance of the photoelectric sensor from being affected. In this embodiment, the material of the light-transmitting layer includes silicon oxide, silicon nitride, silicon oxynitride, or silicon carbide. As an example, the material of the light-transmitting layer is silicon oxide. Silicon oxide has high process compatibility, low cost, and good light-transmitting and insulating properties.

[0096] Figures 7 to 11 It is a schematic structural diagram corresponding to each step in an embodiment of the method for forming the photoelectric sensor of the present invention.

[0097] With reference to Figures 7 to 9 , Figure 7 (a) is a top view of the substrate, Figure 7 (b) is Figure 7 a partial enlarged view of any photosensitive pixel region in (a), Figure 8 is Figure 7 a cross-sectional view corresponding to (a), Figure 9 is Figure 8 a top view of

[0098]

[0099]

[0100]

[0101] The substrate 100 is used to provide a process platform for subsequent process steps.

[0102] In this embodiment, the substrate 100 includes a substrate 120 and a first interconnect structure layer 130 located on the substrate 120.

[0102] In this embodiment, the material of the substrate 120 includes silicon, and the substrate 120 is a silicon substrate. In other embodiments, the material of the substrate may also be other materials such as germanium, silicon germanide, silicon carbide, gallium arsenide, or indium gallium arsenide, and the substrate may also be other types of substrates such as a silicon-on-insulator substrate or a germanium-on-insulator substrate.

[0103] In this embodiment, the substrate 100 is a pixel wafer, including a first surface 102 where the first interconnect structure layer 130 is located, and a second surface opposite to the first surface 102.

[0104] In this embodiment, the substrate 100 is a backside illumination (BSI) pixel wafer, and receives light from its second surface.

[0105] Correspondingly, in this embodiment, the photoelectric sensor is a backside illumination photoelectric sensor.

[0106] In other embodiments, the substrate may also be a frontside illumination (FSI) pixel wafer, and receives light from its first surface.

[0107] In this embodiment, only a part of the photosensitive pixel region P and the pixel unit region 100a are shown in the figure. The pixel unit region 100a may further include device structures such as optoelectronic elements (e.g., photodiodes). Among them, the photodiode may be a backside illumination single photon avalanche diode (SPAD). For the purpose of simplification, the detailed structures of the above components are not shown in the embodiments of the present invention.

[0108] In this embodiment, the substrate 100 is defined as the first substrate 100, and the photoelectric sensor further includes: a second substrate (not shown), which is used as a logic wafer and is bonded to the first surface 102 of the first substrate 100.

[0109] The second substrate serves as a logic wafer and is used to analyze and process the electrical signals provided by the pixel wafer.

[0110] By separately arranging the photosensitive pixel region P and the logic region on two wafers and bonding the pixel wafer and the logic wafer together, a larger pixel area can be obtained, which is beneficial to shortening the path of light reaching the optoelectronic element, reducing the scattering of light, making the light more focused, thereby improving the photosensitive ability of the photoelectric sensor in low-light environments and reducing system noise and crosstalk.

[0111] In this embodiment, the substrate 120 of the first substrate 100 is the first substrate 120, and the second substrate includes a second substrate 220 and a second interconnect structure layer 210 located on the second substrate 220.

[0112] In this embodiment, the material of the second substrate 220 includes silicon, and the second substrate 220 is a silicon substrate. In other embodiments, the material of the second substrate may also be other materials such as germanium, silicon germanide, silicon carbide, gallium arsenide or indium gallium, and the second substrate may also be other types of substrates such as silicon-on-insulator substrate or germanium-on-insulator substrate.

[0113] Correspondingly, in this embodiment, a logic transistor (not shown in the figure) is further formed in the second substrate, and the logic transistor is used to perform logic processing on the electrical signals provided by the pixel wafer. Specifically, the logic transistor may include a logic gate structure located on the second substrate, and a logic drain region and a logic source region in the second substrate on both sides of the logic gate structure respectively.

[0114] As an embodiment, the bonding between the first substrate 100 and the second substrate is achieved by means of hybrid bonding.

[0115] Specifically, in this embodiment, the pixel wafer and the logic wafer can be bonded together by using dielectric bonding, and then the electrical connection between the first interconnect structure layer 130 and the second interconnect structure layer 210 is performed.

[0116] Among them, the first interconnect structure layer 130 may be a first metal wire, or the first interconnect structure layer 130 is a first through-silicon via interconnect structure (TSV), or the first interconnect structure layer 130 includes a first via interconnect structure and a first metal wire located on the first via interconnect structure; the second interconnect structure layer 210 may be a second metal wire, or the second interconnect structure layer 210 is a second through-silicon via interconnect structure (TSV), or the second interconnect structure layer 210 includes a second via interconnect structure and a second metal wire located on the second via interconnect structure.

[0117] It should be noted that the above method for realizing the bonding between the first substrate 100 and the second substrate is only taken as an embodiment, and the bonding method between the first substrate 100 and the second substrate is not limited to this. For example: in other embodiments, the bonding method between the first substrate and the second substrate may also be direct bonding (such as fusion bonding and anodic bonding) or indirect bonding techniques (such as metal eutectic, thermocompression bonding and adhesive bonding), etc.

[0118] In this embodiment, the substrate 100 has a light-receiving surface 101. Among them, the light-receiving surface 101 refers to the surface for receiving light.

[0119] The photosensitive pixel region P is used to receive optical signals so as to convert the optical signals into electrical signals.

[0120] In the substrate 100, the number of the photosensitive pixel regions P is multiple, and the multiple photosensitive pixel regions P are arranged in a matrix. The pixel unit region 100a is used to form pixels, and the sub-unit regions 100b of each pixel unit region 100a are used to receive optical signals simultaneously.

[0121] In this embodiment, in the step of providing the substrate 100, each pixel unit area 100a has four sub-unit areas 100b arranged in an array, and the intersection lines 201 between the four sub-unit areas 100b intersect vertically.

[0122] In this embodiment, each pixel unit area 100a is divided into a plurality of sub-unit areas 100b arranged in an array. When the pixel unit area 100a receives light, the four sub-unit areas 100b sense light simultaneously when the pixel unit area 100a receives light, which is four-phase (Quad Phase Detection, QPD) focusing. Each pixel unit area 100a has a lens, and each sub-unit area 100b corresponds to a photodiode under each lens, that is, a total of four photodiodes sense light simultaneously and output electrical signals with phases. Subsequently, the four sub-unit areas 100b are combined in pairs, and their phase differences are compared with a reference value to achieve phase focusing.

[0123] Correspondingly, the intersection lines 201 divide the pixel unit area 100a into four sub-unit areas 100b arranged in a "field" - shaped array.

[0124] In this embodiment, in the step of providing the substrate 100, the pixel unit area 100a has a preset light - receiving area 100c located at the intersection of the intersection lines 201 and covering a partial area near the intersection of the four sub-unit areas 100b.

[0125] The preset light - receiving area 100c is the area of the pixel unit area 100a where light converges on the light - receiving surface 101 when preset light is received.

[0126] In this embodiment, in the step of providing the substrate 100, in each pixel unit area 100a, the intersection of the intersection lines 201 is the center point of the pixel unit area 100a.

[0127] If the intersection of the intersection lines 201 is the center point of the pixel unit area 100a, the sub-unit areas 100b divided by the intersection lines 201 are evenly arranged, and the light - sensing areas of the respective sub-unit areas 100b are similar, making the light - sensing of each sub-unit area 100b more uniform and making the focusing of the pixel unit area 100a more accurate.

[0128] Combined with reference Figure 10 and Figure 11 , Figure 10 is Figure 8 the partial enlarged view of the area within the dashed box in Figure 11 is Figure 9The corresponding top view forms a light-shielding structure 310 that penetrates through a partial thickness of the substrate 100 on one side of the light-receiving surface 101. The light-shielding structure 310 is located in the substrate 100 between adjacent pixel unit regions 100a and between adjacent sub-unit regions 100b; a light-splitting structure 320 that penetrates through a partial thickness of the substrate 100 on one side of the light-receiving surface 101 is formed. The light-splitting structures 320 are correspondingly distributed in each sub-unit region 100b, and the extending direction of each light-splitting structure 320 forms an acute angle with the row direction (such as the X direction shown in Figure 11 ), or the column direction (such as the Y direction shown in Figure 11 ).

[0129] Correspondingly, in this embodiment, the light-shielding structure 310 is formed at the position of the boundary line 301 to divide the pixel unit region 100a into multiple sub-unit regions 100b.

[0130] The light-shielding structure 310 is used to prevent optical crosstalk between adjacent pixels and is also used to divide adjacent sub-unit regions 100b.

[0131] Specifically, the light-shielding structure 310 has a light-blocking effect on light. The light-shielding structure 310 is located between the light-transmitting layers of adjacent pixel unit regions 100a. When incident light irradiates the photosensitive pixel region P, the incident light can only enter the corresponding pixel unit region 100a through the light-transmitting layer, and cannot pass through the light-shielding structure 310 around the light-transmitting layer to enter adjacent other pixel unit regions 100a, thus avoiding optical crosstalk to other pixel unit regions 100a.

[0132] In this embodiment, the material of the light-shielding structure 310 is a conductive material. Conductive materials are usually light-impermeable, thus meeting the function of the light-shielding structure 310 for light shielding.

[0133] As an example, the conductive material can be a metal material. Specifically, the material of the light-shielding structure 310 includes one or more of W, Al, Cu, Ti, TiN, Ta, and TaN. In this embodiment, the material of the light-shielding structure 310 is W.

[0134] In other embodiments, the conductive material can also be polysilicon doped with conductive ions.

[0135] The light-splitting structure 320 is used to split the light incident on the sub-unit region 100b. Specifically, the extending direction of each light-splitting structure 320 forms an acute angle with the row direction or the column direction of the array arrangement. When light is incident on the sub-unit region 100b, it is reflected by the light-splitting structure 320 and dispersed into the corresponding sub-unit region 100b.

[0136] In this embodiment, each pixel unit area 100a is divided into a plurality of sub-unit areas 100b arranged in an array. When the pixel unit area 100a receives light, the plurality of sub-unit areas 100b sense light simultaneously, and then the plurality of sub-unit areas 100b are aligned to achieve the focusing of the pixel unit area 100a. Then, when each pixel unit area 100a receives light, when the light spot is relatively concentrated at the junction of the plurality of sub-unit areas 100b, a light splitting effect is achieved, enabling the light to be better dispersed into the corresponding sub-unit areas 100b, which is beneficial to increasing the effective light-sensing area of each sub-unit area 100b, making the light sensing of each sub-unit area 100b more uniform. Correspondingly, it is beneficial to reduce the non-uniformity of light sensing between the plurality of sub-unit areas 100b, thereby facilitating more accurate focusing of the pixel unit area 100a and further improving the focusing performance of the photoelectric sensor.

[0137] In this embodiment, the boundary line 201 extends to divide the pixel unit area 100a. Correspondingly, in this embodiment, in the step of forming the light splitting structure 320 that penetrates through a partial thickness of the substrate 100 on one side of the light receiving surface 101, the extending direction of each light splitting structure 320 has an acute angle with the extending direction of the boundary line 201.

[0138] In this embodiment, in the step of forming the light splitting structure 320 that penetrates through a partial thickness of the substrate 100 on one side of the light receiving surface 101, in each pixel unit area 100a, the extending direction of the light splitting structure 320 passes through the intersection point of the boundary lines 201.

[0139] Since the extending direction of the light splitting structure 320 passes through the intersection point of the boundary lines 201, the light splitting structure 320 in each sub-unit area 100b points to the center of the preset light receiving area 100c, making the light splitting effect of the light splitting structure 320 on the light incident on the preset light receiving area 100c more uniform in each sub-unit area 100b.

[0140] In this embodiment, in the step of forming the light splitting structure 320 that penetrates through a partial thickness of the substrate 100 on one side of the light receiving surface 101, in each pixel unit area 100a, the light splitting structure 320 extends into the light receiving area 100c.

[0141] In each pixel unit area 100a, the light splitting structure 320 extends into the light receiving area 100c, enabling the incident light in each sub-unit area 100b to be split.

[0142] In this embodiment, in the step of forming the light splitting structure 320 that penetrates through a partial thickness of the substrate 100 on one side of the light receiving surface 101, the morphology of the light splitting structure 320 is strip-shaped.

[0143] If the morphology of the light splitting structure 320 is strip-shaped, it can split as much incident light as possible while minimizing the occupied space of the light splitting structure 320.

[0144] It should be noted that in this embodiment, in the step of forming the light splitting structure 320 that penetrates a partial thickness on one side of the light receiving surface 101 of the substrate 100, the length of the light splitting structure 320 should not be too large or too small. If the length of the light splitting structure 320 is too large, it is likely to cause unnecessary waste and make it difficult to form the light splitting structure 320. If the length of the light splitting structure 320 is too small, it is likely to result in too few regions where the incident light can be split, insufficient light splitting effect of the light splitting structure 320 on the incident light, affecting the light splitting effect of the light splitting structure 320, and making it difficult to achieve the effect of more uniform photosensitivity of each sub-unit region 100b. Therefore, in this embodiment, in the step of forming the light splitting structure 320 that penetrates a partial thickness on one side of the light receiving surface 101 of the substrate 100, the length of the light splitting structure 320 is 200 nm to 600 nm.

[0145] It should also be noted that in this embodiment, in the step of forming the light splitting structure 320 that penetrates a partial thickness on one side of the light receiving surface 101 of the substrate 100, the width of the light splitting structure 320 should not be too large or too small. If the width of the light splitting structure 320 is too large, it is likely to occupy too much space of the sub-unit region 100b and cause unnecessary waste. If the width of the light splitting structure 320 is too small, it is likely to make it difficult to form the light splitting structure 320. Therefore, in this embodiment, in the step of forming the light splitting structure 320 that penetrates a partial thickness on one side of the light receiving surface 101 of the substrate 100, the width of the light splitting structure 320 is 100 nm to 300 nm.

[0146] It should also be noted that in this embodiment, in the step of forming the light splitting structure 320 that penetrates a partial thickness on one side of the light receiving surface 101 of the substrate 100, the angle between the extending direction of the light splitting structure 320 and the row direction or column direction of the array arrangement should not be too large or too small. If the angle between the extending direction of the light splitting structure 320 and the row direction or column direction of the array arrangement is too large or too small, it is likely to cause the extending direction of the light splitting structure 320 to be too close to the row direction or column direction, still resulting in the incident light being too concentrated, and making it difficult to achieve a good light splitting effect and the effect of more uniform photosensitivity of each sub-unit region 100b. Therefore, in this embodiment, in the step of forming the light splitting structure 320 that penetrates a partial thickness on one side of the light receiving surface 101 of the substrate 100, the angle between the extending direction of the light splitting structure 320 and the row direction or column direction of the array arrangement is 30° to 60°.

[0147] Specifically, in this embodiment, in the step of forming the light splitting structure 320 of the substrate 100 with a partial thickness penetrating one side of the light receiving surface 101, the extension direction of the light splitting structure 320 forms an angle of 45° with the row direction or the column direction of the array arrangement, which is beneficial to further achieving better dispersion of the incident light into the corresponding sub-unit regions 100b, further beneficial to increasing the effective photosensitive area of each sub-unit region 100b, and further beneficial to making the photosensitivity of each sub-unit region 100b more uniform.

[0148] In this embodiment, the step of forming the light blocking structure 310 of the substrate 100 with a partial thickness penetrating one side of the light receiving surface 101 includes: patterning the substrate 100 to form first grooves in the substrate 100 located between adjacent pixel unit regions 100a and between adjacent sub-unit regions 100b.

[0149] The first grooves are used to form the light blocking structure 310.

[0150] In this embodiment, the first grooves are filled to form the light blocking structure 310.

[0151] In this embodiment, the step of forming the light splitting structure 320 of the substrate 100 with a partial thickness penetrating one side of the light receiving surface 101 includes: patterning the substrate 100 to form second grooves distributed in the substrate 100 of each sub-unit region 100b.

[0152] The second grooves are used to form the light splitting structure 320.

[0153] In this embodiment, the second grooves are filled to form the light splitting structure 320.

[0154] In this embodiment, in the same step, the first grooves and the second grooves are filled. Therefore, in this embodiment, the light splitting structure 320 and the light blocking structure 310 are made of the same material.

[0155] Correspondingly, in this embodiment, the material of the light splitting structure 320 is a conductive material. The conductive material is usually light-impermeable, so that the light splitting structure 320 can play a role in light splitting.

[0156] As an example, the conductive material can be a metal material. Specifically, the material of the light splitting structure 320 includes one or more of W, Al, Cu, Ti, TiN, Ta, and TaN. In this embodiment, the material of the light splitting structure 320 is W.

[0157] In other embodiments, the conductive material can also be polysilicon doped with conductive ions.

[0158] In this embodiment, the method for forming the photoelectric sensor further includes: forming a light-transmitting layer covering the light receiving surface 101 of the substrate 100 of each sub-unit region 100b.

[0159] The light-transmitting layer has light-transmitting properties. When the light-transmitting layer is formed on the light-receiving surface 101, light can pass through the light-transmitting layer and irradiate on the light-receiving surface 101.

[0160] In this embodiment, the material of the light-transmitting layer is a light-transmitting material, and moreover, the material of the light-transmitting layer is an insulating material to prevent affecting the electrical performance of the photoelectric sensor. In this embodiment, the material of the light-transmitting layer includes silicon oxide, silicon nitride, silicon oxynitride or silicon carbide. As an example, the material of the light-transmitting layer is silicon oxide. Silicon oxide has high process compatibility, low cost, and good light-transmitting and insulating properties.

[0161] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be subject to the scope defined by the claims.

Claims

1. An optoelectronic sensor, characterized in that, it includes: a substrate having a light-receiving surface, and the substrate includes a photosensitive pixel region, the photosensitive pixel region includes a plurality of pixel unit regions arranged in a matrix, and each pixel unit region is divided into a plurality of sub-unit regions arranged in an array; a light-blocking structure penetrating through a partial thickness of the substrate on the side of the light-receiving surface, and the light-blocking structure is located in the substrate between adjacent pixel unit regions and between adjacent sub-unit regions; a light-splitting structure penetrating through a partial thickness of the substrate on the side of the light-receiving surface, and the light-splitting structures are respectively distributed in each sub-unit region, and the extending direction of each light-splitting structure has an acute angle with the row direction or the column direction of the array arrangement.

2. The optoelectronic sensor according to claim 1, characterized in that, each pixel unit region has four sub-unit regions arranged in an array, and the light-blocking structures between the four sub-unit regions intersect perpendicularly; the extending direction of each light-splitting structure has an acute angle with the extending direction of the light-blocking structure inside the pixel unit region.

3. The optoelectronic sensor according to claim 2, characterized in that, in each pixel unit region, the extending direction of the light-splitting structure passes through the intersection point of the light-blocking structure inside the pixel unit region.

4. The optoelectronic sensor according to claim 2, characterized in that, the pixel unit region has a preset light-receiving region at the intersection point of the light-blocking structure inside it, and the preset light-receiving region covers a partial area of the four sub-unit regions near the intersection point; in each pixel unit region, the light-splitting structure extends into the light-receiving region.

5. The optoelectronic sensor according to claim 4, characterized in that, in each pixel unit region, the intersection point of the light-blocking structure inside it is the center point of the pixel unit region.

6. The optoelectronic sensor according to any one of claims 1 to 5, characterized in that, the morphology of the light-splitting structure is strip-shaped.

7. The optoelectronic sensor according to claim 6, characterized in that, the length of the light-splitting structure is 200 nm to 600 nm; the width of the light-splitting structure is 100 nm to 300 nm.

8. The optoelectronic sensor according to any one of claims 1 to 5, characterized in that, the angle between the extending direction of the light-splitting structure and the row direction or the column direction of the array arrangement is 30° to 60°.

9. The optoelectronic sensor according to claim 8, characterized in that, the angle between the extending direction of the light-splitting structure and the row direction or the column direction of the array arrangement is 45°.

10. The optoelectronic sensor according to claim 1, characterized in that, the light-splitting structure and the light-blocking structure are made of the same material.

11. A method for forming an optoelectronic sensor, characterized in that, it includes: providing a substrate having a light-receiving surface, and the substrate includes a photosensitive pixel region, the photosensitive pixel region includes a plurality of pixel unit regions arranged in a matrix, and each pixel unit region is divided into a plurality of sub-unit regions arranged in an array; forming a light-blocking structure penetrating through a partial thickness of the substrate on the side of the light-receiving surface, and the light-blocking structure is located in the substrate between adjacent pixel unit regions and between adjacent sub-unit regions; A light splitting structure is formed at a partial thickness of the substrate on the light receiving surface side. The light splitting structures are distributed in each of the sub-unit regions in a one-to-one correspondence, and the extending direction of each light splitting structure forms an acute angle with the row direction or the column direction of the array arrangement.

12. The method for forming an optoelectronic sensor according to claim 11, wherein, the step of forming a light blocking structure at a partial thickness of the substrate on the light receiving surface side includes: patterning the substrate to form first grooves in the substrate located between adjacent pixel unit regions and between adjacent sub-unit regions; filling the first grooves to form the light blocking structure; the step of forming a light splitting structure at a partial thickness of the substrate on the light receiving surface side includes: patterning the substrate to form second grooves in the substrate distributed in each of the sub-unit regions; filling the second grooves to form the light splitting structure.

13. The method for forming an optoelectronic sensor according to claim 12, wherein, in the same step, the first grooves and the second grooves are filled.

14. The method for forming an optoelectronic sensor according to claim 11, wherein, in the step of providing the substrate, each pixel unit region has four sub-unit regions arranged in an array, and the intersection lines between the four sub-unit regions intersect perpendicularly; in the step of forming a light splitting structure at a partial thickness of the substrate on the light receiving surface side, the extending direction of each light splitting structure forms an acute angle with the extending direction of the intersection lines.

15. The method for forming an optoelectronic sensor according to claim 14, wherein, in the step of forming a light splitting structure at a partial thickness of the substrate on the light receiving surface side, in each pixel unit region, the extending direction of the light splitting structure passes through the intersection point of the intersection lines.

16. The method for forming an optoelectronic sensor according to claim 14, wherein, in the step of providing the substrate, the pixel unit region has a preset light receiving area located at the intersection point of the intersection lines and covering a partial area of the four sub-unit regions near the intersection point; in the step of forming a light splitting structure at a partial thickness of the substrate on the light receiving surface side, in each pixel unit region, the light splitting structure extends into the light receiving area.

17. The method for forming an optoelectronic sensor according to claim 16, wherein, in the step of providing the substrate, in each pixel unit region, the intersection point of the intersection lines is the center point of the pixel unit region.

18. The method for forming an optoelectronic sensor according to any one of claims 11 to 17, wherein, in the step of forming a light splitting structure at a partial thickness of the substrate on the light receiving surface side, the morphology of the light splitting structure is strip-shaped.

19. The method for forming an optoelectronic sensor according to any one of claims 11 to 17, wherein, in the step of forming a light splitting structure at a partial thickness of the substrate on the light receiving surface side, the angle between the extending direction of the light splitting structure and the row direction or the column direction of the array arrangement is 30° to 60°.

20. The method for forming an optoelectronic sensor according to claim 19, Characterized in that, In the step of forming a spectroscopic structure of a substrate with a partial thickness penetrating one side of the light-receiving surface, the extension direction of the spectroscopic structure forms an angle of 45° with the row direction or the column direction of the array arrangement.

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