Photoelectric detection structure

Abstract

The embodiment of the invention discloses a photoelectric detection structure. The photoelectric detection structure comprises a substrate; a plurality of photosensitive regions on the substrate; and a light guide structure over the plurality of photosensitive regions, the light guide structure comprising: a plurality of interlayer dielectric layers on the photosensitive regions; and a plurality of metal wiring layers alternately stacked with the plurality of interlayer dielectric layers, the plurality of metal wiring layers including at least a first metal wiring layer and a second metal wiring layer located above the first metal wiring layer; wherein the second metal wiring layer includes a light input opening, and the first metal wiring layer includes a first plurality of light conduction openings, and wherein, in a top view, the first plurality of light conduction openings are arranged around the light input opening to form a plurality of inclined light paths for conducting a plurality of paths of light signals to the plurality of photosensitive regions, respectively. According to the embodiment of the invention, the number of photosensitive regions in unit area is at least increased.

Description

Technical Field

[0001] The present application relates to the field of optical communications, and in particular to a photoelectric detection structure. Background Art

[0002] In the field of optical communications, the photosensitive area of ​​the photoelectric detection structure converts the optical signal received from the optical fiber into an electrical signal. Usually, when the photoelectric detection structure receives multi-path optical signals from multiple optical fibers, the multi-path optical signals are vertically incident on multiple photosensitive areas of the photoelectric detection structure. Since the thickness of the optical fiber core layer is relatively large, the distance between adjacent optical signals of the multi-path optical signals emitted from multiple optical fibers is relatively large, and accordingly, the distance between adjacent photosensitive areas of the multiple photosensitive areas in the photoelectric detection structure also needs to be set larger to adapt to the distance between the multiple light signals. However, since the thickness of the core layer of the optical fiber is much larger than the size of the photosensitive area, the distance between the multiple photosensitive areas is relatively large, which causes a waste of the area of ​​the photoelectric detection structure, and the volume of the photoelectric detection structure is also correspondingly large, and the cost is also high. Therefore, it is necessary to increase the number of photosensitive areas per unit area to reduce the waste of the photoelectric detection structure area. Summary of the invention

[0003] In view of the above problems existing in the prior art, the embodiments of the present application propose a photoelectric detection structure that can receive multi-path optical signals from multiple optical fibers. Compared with the prior art, the number of photosensitive areas per unit area is at least increased.

[0004] According to one aspect of the present application, a photoelectric detection structure is provided, which includes: a substrate; a plurality of photosensitive regions located on the substrate; and a light-guiding structure located above the plurality of photosensitive regions, the light-guiding structure including: a plurality of interlayer dielectric layers located on the photosensitive regions; and a plurality of metal wiring layers, which are alternately stacked with the plurality of interlayer dielectric layers, the plurality of metal wiring layers including at least a first metal wiring layer and a second metal wiring layer located above the first metal wiring layer; wherein the second metal wiring layer includes a light input opening, and the first metal wiring layer includes a first plurality of light-conducting openings, wherein, in a top view, the first plurality of light-conducting openings are arranged around the light input openings to form a plurality of inclined optical paths for respectively conducting multiple optical signals to the plurality of photosensitive regions.

[0005] In one or more embodiments, the multiple metal wiring layers also include a third metal wiring layer located between the first metal wiring layer and the second metal wiring layer, the third metal wiring layer includes a second plurality of light-conducting openings, and in the top view, the second plurality of light-conducting openings surround the first plurality of light-conducting openings to form portions of multiple inclined optical paths.

[0006] In one or more embodiments, in a top view, a first plurality of light-conducting openings are arranged to surround a second plurality of light-conducting openings, and a plurality of photosensitive regions are disposed to surround the first plurality of light-conducting openings.

[0007] In one or more embodiments, the second plurality of light conducting openings are connected to each other to form an annular opening whose center is filled with a portion of the second metal wiring layer.

[0008] In one or more embodiments, the first plurality of light conducting openings are connected to each other to form an annular opening whose center is filled with a portion of the first metal wiring layer.

[0009] In one or more embodiments, the second plurality of light conducting openings are spaced apart from one another and the first plurality of light conducting openings are spaced apart from one another.

[0010] In one or more embodiments, the photodetection structure further includes a first isolation structure located in the first interlayer dielectric layer between the photosensitive region and the first metal wiring layer, and in a top view, the first isolation structure is located between the plurality of photosensitive regions and the light input opening.

[0011] In one or more embodiments, the photodetection structure further includes a second isolation structure located in the second interlayer dielectric layer between the first metal wiring layer and the third metal wiring layer, wherein in a top view, the second isolation structure is located between the first plurality of light-conducting openings and the light input openings.

[0012] In one or more embodiments, the first isolation structure and the second isolation structure are continuous ring-shaped or are a plurality of isolation blocks spaced apart from each other.

[0013] In one or more embodiments, the photodetection structure also includes a third isolation structure located in the first interlayer dielectric layer between the multiple photosensitive regions and the first metal wiring layer. In the top view, the third isolation structure is located on the outside of the multiple photosensitive regions away from the light input opening and surrounds the multiple photosensitive regions.

[0014] In one or more embodiments, the photodetection structure also includes a fourth isolation structure located in the second interlayer dielectric layer between the first metal wiring layer and the third metal wiring layer, and in the top view, the fourth isolation structure is located on the outside of the first plurality of light-conducting openings away from the light input openings and surrounds the first plurality of light-conducting openings.

[0015] In one or more embodiments, the photodetection structure further includes an insulating layer located above the light guiding structure.

[0016] The beneficial effects of the above technical solution include: the embodiments of the present application are formed above the multiple photosensitive areas of the photoelectric detection structure, including a light-guiding structure of multiple interlayer dielectric layers and multiple metal wiring layers arranged alternately, and the first multiple light-conducting openings of the first metal wiring layer are arranged around the light input openings of the second metal wiring layer to form multiple inclined light paths for transmitting multiple light signals to the multiple photosensitive areas. In this way, the multiple light signals from multiple optical fibers can be obliquely passed through the multiple interlayer dielectric layers and the first multiple light-conducting openings after being input from the light input openings, so as to be respectively transmitted to the multiple photosensitive areas, so that the setting of the multiple photosensitive areas is no longer limited by the thickness of the optical fiber core layer, thereby at least increasing the number of photosensitive areas per unit area. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings required for use in the embodiments are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can also be obtained based on these drawings without creative work. It is worth noting that according to the standard practice of the industry, the various components are not drawn to scale and are only used for illustration purposes. In fact, for the clarity of discussion, the size of each component can be arbitrarily increased or reduced.

[0018] Figures 1A to 1E Schematic cross-sectional views and top views of a photodetection structure, a second metal wiring layer, a third metal wiring layer, a first metal wiring layer, and a photosensitive region according to an embodiment of the present application are respectively shown.

[0019] FIG. 2A to FIG. 2E A schematic cross-sectional view and a top view are respectively shown of a photodetection structure including an isolation structure, a second metal wiring layer, a third metal wiring layer, a first metal wiring layer and a photosensitive area according to another embodiment of the present application.

[0020] FIG. 3A to FIG. 3E A schematic cross-sectional view and a top view are respectively shown of a photodetection structure including an isolation structure, a second metal wiring layer, a third metal wiring layer, a first metal wiring layer and a photosensitive area according to another embodiment of the present application.

[0021] FIG. 4A to FIG. 4E Schematic cross-sectional views and top views of a photodetection structure, a second metal wiring layer, a third metal wiring layer, a first metal wiring layer, and a photosensitive region according to another embodiment of the present application are shown.

[0022] FIG. 5A to FIG. 5E A schematic cross-sectional view and a top view are respectively shown of a photodetection structure including an isolation structure, a second metal wiring layer, a third metal wiring layer, a first metal wiring layer and a photosensitive area according to another embodiment of the present application.

[0023] FIG. 6A to FIG. 6E A schematic cross-sectional view and a top view are respectively shown of a photodetection structure including an isolation structure, a second metal wiring layer, a third metal wiring layer, a first metal wiring layer and a photosensitive area according to another embodiment of the present application.

[0024] 7A to 7E Schematic cross-sectional views and top views of a photodetection structure, a second metal wiring layer, a third metal wiring layer, a first metal wiring layer, and a photosensitive region according to another embodiment of the present application are shown.

[0025] FIG. 8A to FIG. 8E A schematic cross-sectional view and a top view are respectively shown of a photodetection structure including an isolation structure, a second metal wiring layer, a third metal wiring layer, a first metal wiring layer and a photosensitive area according to another embodiment of the present application.

[0026] 9A to 9E A schematic cross-sectional view and a top view are respectively shown of a photodetection structure including an isolation structure, a second metal wiring layer, a third metal wiring layer, a first metal wiring layer and a photosensitive area according to another embodiment of the present application.

[0027] FIG. 10A to FIG. 10E A schematic cross-sectional view and a top view are respectively shown of a photodetection structure including an isolation structure, a second metal wiring layer, a third metal wiring layer, a first metal wiring layer and a photosensitive area according to another embodiment of the present application.

[0028] FIG. 11A to FIG. 11C Schematic top views of different forms of isolation blocks are shown respectively.

[0029] FIG. 12A to FIG. 12E Schematic cross-sectional views and top views of a photodetection structure, a second metal wiring layer, a third metal wiring layer, a first metal wiring layer, and a photosensitive region according to another embodiment of the present application are shown.

[0030] FIG. 13A to FIG. 13E Schematic cross-sectional views and top views of a photodetection structure, a second metal wiring layer, a third metal wiring layer, a first metal wiring layer, and a photosensitive region according to another embodiment of the present application are shown.

[0031] FIG. 14A to FIG. 14E Schematic cross-sectional views and top views of a photodetection structure, a second metal wiring layer, a third metal wiring layer, a first metal wiring layer, and a photosensitive region according to another embodiment of the present application are shown.

[0032] FIG. 15A to FIG. 15E Schematic cross-sectional views and top views of a photodetection structure, a second metal wiring layer, a third metal wiring layer, a first metal wiring layer, and a photosensitive region according to another embodiment of the present application are shown.

[0033] FIG. 16A to FIG. 16E A schematic cross-sectional view and a top view are respectively shown of a photodetection structure including an isolation structure, a second metal wiring layer, a third metal wiring layer, a first metal wiring layer and a photosensitive area according to another embodiment of the present application.

[0034] FIG. 17A to FIG. 17E A schematic cross-sectional view and a top view are respectively shown of a photodetection structure including an isolation structure, a second metal wiring layer, a third metal wiring layer, a first metal wiring layer and a photosensitive area according to another embodiment of the present application.

[0035] FIG. 18A to FIG. 18E A schematic cross-sectional view and a top view are respectively shown of a photodetection structure including an isolation structure, a second metal wiring layer, a third metal wiring layer, a first metal wiring layer and a photosensitive area according to another embodiment of the present application. DETAILED DESCRIPTION

[0036] The following disclosure provides many different embodiments or examples for realizing different features of the provided subject matter. Specific examples of components and arrangements will be described below to simplify the present invention. Of course, these are merely examples and are not intended to limit the present invention. For example, in the following description, forming a first component above or on a second component may include an embodiment in which the first component and the second component are in direct contact, and may also include an embodiment in which an additional component is formed between the first component and the second component so that the first component and the second component may not be in direct contact. Moreover, the present invention may repeatedly refer to numbers and / or letters in various examples. This repetition is only for simplicity and clarity, and does not itself represent the relationship between the various embodiments and / or configurations discussed.

[0037] Furthermore, for ease of description, spatially relative terms such as "below," "beneath," "lower," "above," and the like may be used herein to describe the relationship of one element or component to another (or additional) elements or components as shown in the figures. The spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein should likewise be interpreted accordingly.

[0038] In addition, the embodiments in the present application and the features in the embodiments may be combined with each other in the absence of conflicts. The present application will be described in detail below with reference to the accompanying drawings and in conjunction with the embodiments. It should be understood that the specific structures shown in the drawings are only for the sake of convenience of explanation and are not intended to limit the present application. When describing a specific figure, other structures not described in the drawings may be provided according to actual needs and are not intended to limit the present application.

[0039] In view of the technical problem in the prior art that the arrangement of photosensitive areas in the photoelectric detection structure is limited by the thickness of the core and cladding in the optical fiber, resulting in a waste of area, the embodiment of the present application proposes a photoelectric detection structure that can receive multi-path light from multiple optical fibers (hereinafter referred to as the multi-path photoelectric detection structure). By forming a light-guiding structure with multiple inclined light paths above multiple photosensitive areas, multiple optical fibers can be arranged obliquely above the light input opening, so that the multi-path light from multiple optical fibers can be input into the light-guiding structure from one light input opening, and transmitted to multiple photosensitive areas through multiple inclined light paths. In this way, the arrangement of multiple photosensitive areas is no longer limited by the thickness of the optical fiber core layer, but can be arranged closer, thereby increasing the number of photosensitive areas per unit area. In the case of having the same number of photosensitive areas, compared with the prior art, the photoelectric detection structure provided by the present application is also smaller in size, and accordingly, the cost is further reduced. In the following, an exemplary embodiment of the above-mentioned photoelectric detection structure will be described with reference to the accompanying drawings.

[0040] Figure 1A is a schematic cross-sectional view of a photodetection structure 100a according to an embodiment of the present application, Figures 1B to 1E They are shown respectively Figure 1A 124b, the third metal wiring layer 124c, the first metal wiring layer 124a, and the photosensitive region 114. Figures 1A to 1E , the photodetection structure 100a includes a substrate 112, a plurality of photosensitive regions 114 located on the substrate 112, and a light-guiding structure 120 located above the plurality of photosensitive regions 114. The light-guiding structure 120 includes a plurality of interlayer dielectric layers 122 located on the plurality of photosensitive regions 114 and a plurality of metal wiring layers 124 arranged alternately with the plurality of interlayer dielectric layers 122, the plurality of metal wiring layers 124 including at least a first metal wiring layer 124a and a second metal wiring layer 124b located above the first metal wiring layer 124a, the first metal wiring layer 124a including a first plurality of light-conducting openings 126, and the second metal wiring layer 124b including a light input opening 128. In a top view, the first plurality of light-conducting openings 126 are arranged around the light input opening 128 to form a plurality of inclined optical paths for conducting the multi-path optical signals 116 to the plurality of photosensitive regions 114. It is easy to understand that the second metal wiring layer 124b is the topmost metal wiring layer of the light guide structure 120, and the number of the first plurality of light conduction openings 126 should be equal to or greater than the number of the multiple optical signals 116, and the number of the plurality of photosensitive regions 114 is equal to or greater than the number of the first plurality of light conduction openings 126. In addition, the plurality of photosensitive regions 114 located on the substrate 112 may be partially filled with the substrate 112 (i.e., the photosensitive region 114 is embedded in the substrate 112 and the top surface of the photosensitive region 114 is flush with the top surface of the substrate 112) or filled with dielectric material.

[0041] In the photoelectric detection structure 100a provided in the embodiment of the present application, by forming a light-guiding structure 120 with an inclined optical path above a plurality of photosensitive regions 114, a plurality of optical fibers 118 can be arranged obliquely around the light input opening 128 above the light input opening 128, without the need to be arranged transversely spaced apart perpendicularly to the photoelectric detection structure as in the prior art, so that the multi-path light 116 from the plurality of optical fibers 118 can be input into the light-guiding structure 120 from a single light input opening 128, and transmitted to the plurality of photosensitive regions 114 respectively through a plurality of inclined optical paths, so that the arrangement of the plurality of photosensitive regions 114 is no longer limited by the thickness of the core layer of the optical fiber 118, but can be arranged closer, thereby increasing the number of photosensitive regions 114 per unit area. Accordingly, the volume of the photoelectric detection structure 100a is significantly reduced. In the case of having the same number of photosensitive regions 114, the volume of the photoelectric detection structure 100a provided in the present application is also smaller than that of the prior art, and accordingly, the cost is further reduced.

[0042] In some embodiments, the plurality of metal wiring layers 124 may further include a third metal wiring layer 124c located between the first metal wiring layer 124a and the second metal wiring layer 124b, the third metal wiring layer 124c including a second plurality of light conducting openings 130, and in a top view, the second plurality of light conducting openings 130 surround the first plurality of light conducting openings 126 to form a portion of a plurality of inclined light paths. In some embodiments, the plurality of interlayer dielectric layers 122 may further include a first interlayer dielectric layer located on the plurality of photosensitive regions 114, a second interlayer dielectric layer located on the first metal wiring layer 124a and the third metal wiring layer 124c, and a third interlayer dielectric layer located between the third metal wiring layer 124c and the second metal wiring layer 124b. It is easy to understand that after the plurality of optical signals 116 are input from the optical input openings 128, the plurality of optical signals 116 are sequentially obliquely passed through the third interlayer dielectric layer, the second plurality of optical conductive openings 130, the second interlayer dielectric layer, the first plurality of optical conductive openings 126, and the first interlayer dielectric layer to be respectively conducted to the plurality of photosensitive regions 114. Although the structure above the photosensitive region is referred to as the light guide structure 120, a conductive structure may be formed in the light guide structure 120 to conduct the electrical signal converted by the photosensitive region 114. For example, a conductive structure may be formed in a certain area of ​​the plurality of photosensitive regions 114 (for example, in a region perpendicular to Figure 1A A plurality of conductive structures are formed on the second dielectric layer 124a (in the area in the paper direction), and the plurality of conductive structures are electrically connected to the first metal wiring layer 124a. Then, a plurality of contact structures are respectively formed in the second dielectric layer and the third dielectric layer to electrically connect the plurality of photosensitive regions 114 to the second metal wiring layer 124c. In this way, after the photosensitive region 114 converts the optical signal into an electrical signal, the electrical signal can be conducted out.

[0043] It is easy to understand that the number of the second plurality of light-conducting openings 130 should be equal to or greater than the number of the multiple light beams. Figures 1A to 1D In the figure, only three metal wiring layers 124 are shown, but it should be understood that the number of metal wiring layers can be increased or decreased according to specific requirements. Figures 1A to 1D It is shown that the photoelectric detection structure 100a can receive four optical signals. It is understood that the present application is not limited thereto, and the number of optical signals received by the photoelectric detector structure can be adjusted according to actual conditions. In the following description, for ease of description, the axis perpendicular to the center of the light input opening 128 is taken as the central axis.

[0044] exist Figures 1A to 1D In the illustrated embodiment, the second plurality of light-conducting openings 130 are arranged around the central axis, and each light-conducting opening in the second plurality of light-conducting openings 130 partially overlaps with the light input opening 128 in the vertical direction. Accordingly, the first plurality of light-conducting openings 126 are arranged around the second plurality of light-conducting openings 130, and one light-conducting opening in the first plurality of light-conducting openings 126 partially overlaps with a corresponding one light-conducting opening in the second plurality of light-conducting openings 130 in the vertical direction. In addition, the plurality of photosensitive regions 114 are also arranged around the first plurality of light-conducting openings 126, and one photosensitive region in the plurality of photosensitive regions 114 partially overlaps with a corresponding one light-conducting opening in the first plurality of light-conducting openings 126 in the vertical direction. In general, as each metal wiring layer is farther away from the light input opening 128, the spacing between the light conduction openings in the corresponding metal wiring layer becomes larger, to ensure that the light input opening 128 and the multiple light conduction openings on other metal wiring layers respectively form multiple inclined light paths, so that the multiple obliquely incident light signals 116 can be transmitted to the multiple photosensitive areas 114.

[0045] In some embodiments, the photodetection structure 100a may further include an insulating layer 134 located above the light-guiding structure 120. Throughout this document, the plurality of interlayer dielectric layers 122 and the insulating layer 134 should be transparent materials or semi-transparent materials, such as polyimide (PI), silicon oxide, or other insulating materials, and the metal wiring layer 124 should be an opaque or poorly transparent material, such as metal, alloy, etc. The photosensitive region 114, the plurality of interlayer dielectric layers 122, the plurality of metal wiring layers 124, and the first plurality of light-conducting openings 126 and the second plurality of light-conducting openings 130 may be formed by conventional methods known in the art.

[0046] exist Figures 1A to 1EIn the illustrated embodiment, the light input opening 128, the first plurality of light transmission openings 126, the second plurality of light transmission openings 130, and the photosensitive area 114 are all in the shape of a square. In other embodiments, the light input opening 128, the first plurality of light transmission openings 126, the second plurality of light transmission openings 130, and the photosensitive area 114 may be in any suitable shape, such as a rectangle, a circle, a sector, etc. In addition, the number of light paths may also be 8, 16, etc.

[0047] Figure 2A FIG. 4 shows a cross-sectional schematic diagram of a photodetection structure 100 b including an isolation structure according to another embodiment of the present application. FIG. 2B to FIG. 2E They are shown respectively Figure 2A A schematic top view showing the relative positions of the second metal wiring layer 124b, the third metal wiring layer 124c, the first metal wiring layer 124a, and the photosensitive region 114 and the isolation structure. FIG. 2A to FIG. 2E The photodetection structure 100b shown is Figures 1A to 1E The photodetection structure 100a shown is similar, and only the differences are described below. The photodetection structure 100b may also include an isolation structure adjacent to the photosensitive area 114 or the light-conducting opening in the top view to prevent interference between the target light path and other light paths. The isolation structure may be arranged in the interlayer dielectric layer above the photosensitive area 114, the first plurality of light-conducting openings 126, and the second plurality of light-conducting openings 130, respectively, to isolate the light paths in the photosensitive area 114, the first plurality of light-conducting openings 126, and the second plurality of light-conducting openings 130, respectively. The isolation structure (for example, the first isolation structure 136, the second isolation structure 138, the third isolation structure 140, the fourth isolation structure 142, and the fifth isolation structure 144 mentioned below) may be formed by a conductive structure, for example, the isolation structure located in the first dielectric layer may be referred to as a via, and the isolation structure located in other interlayer dielectric layers may be referred to as a contact.

[0048] In one embodiment, the photodetection structure 100b further includes a first isolation structure 136 in the first interlayer dielectric layer, and in a top view, the first isolation structure 136 is located between the plurality of photosensitive regions 114 and the light input opening 128. The photodetection structure 100b may further include a second isolation structure 138 in the second interlayer dielectric layer, and in a top view, the second isolation structure 138 is located between the first plurality of light conduction openings 126 and the light input opening 128. In other words, the vertical projection of the first isolation structure 136 on the plurality of photosensitive regions 114 is located between the plurality of photosensitive regions 114 and the vertical projection of the light input opening 128 on the plurality of photosensitive regions 114. The vertical projection of the second isolation structure 138 on the first metal wiring layer 124a is located between the vertical projection of the first plurality of light conduction openings 126 and the light input opening 128 on the first metal wiring layer 124a. That is, in the top view, the first isolation structure 136 and the second isolation structure 138 are respectively disposed on the inner side of the plurality of photosensitive regions 114 and the first plurality of light-conducting openings 126 close to the central axis to avoid interference between optical signals.

[0049] In detail, when the optical signal passes through the multiple interlayer dielectric layers 122, since the interlayer dielectric layers have a certain light-conducting ability, when the light passes through the interlayer dielectric layers, the interlayer dielectric layers will conduct the optical signal to other positions of the interlayer dielectric layers of the same layer, and the optical signal conducted to other positions of the optical conduction openings may be conducted to the optical conduction openings or photosensitive areas below. Therefore, the provision of the first isolation structure 136 and the second isolation structure 138 can avoid the interference of the light conducted to the inside of the optical conduction openings with the normal optical path. Generally speaking, in a top view, the first isolation structure 136 and the second isolation structure 138 are arranged close to the multiple photosensitive areas 114 and the first multiple optical conduction openings 126 to block the overflow of the optical signal as much as possible. Although FIG. 2A to FIG. 2E The first isolation structure 136 and the second isolation structure 138 are shown as continuous square rings, but it is easy to understand that the first isolation structure 136 and the second isolation structure 138 can also be other suitable shapes, such as circular rings or rectangular rings.

[0050] FIG. 3A to FIG. 3E A cross-sectional schematic diagram of a photodetection structure 100c according to another embodiment of the present application and a schematic top view of the relative positions of the second metal wiring layer 124b, the third metal wiring layer 124c, the first metal wiring layer 124a and the photosensitive area 114 and the isolation structure are respectively shown. FIG. 3A to FIG. 3E The photodetection structure 100c shown is Figure 2AThe photodetection structure 100c is similar to the photodetection structure 100b shown, and only the differences are described below. In some embodiments, the photodetection structure 100c also includes a third isolation structure 140 located in the first interlayer dielectric layer, and in the top view, the third isolation structure 140 is located outside the multiple photosensitive regions 114 away from the central axis and surrounds the multiple photosensitive regions 114. Further, the photodetection structure 100c may also include a fourth isolation structure 142 located in the second interlayer dielectric layer, and in the top view, the fourth isolation structure 142 is located outside the first multiple light-conducting openings 126 away from the central axis and surrounds the first multiple light-conducting openings 126. In some embodiments, the photodetection structure 100c also includes a fifth isolation structure 144 located in the third interlayer dielectric layer, and the fifth isolation structure 144 is located outside the second multiple light-conducting openings 130 and surrounds the second multiple light-conducting openings 130. Although FIG. 3A to FIG. 3E The third isolation structure 140, the fourth isolation structure 142 and the fifth isolation structure 144 are shown as continuous square rings, but it is not difficult to understand that the third isolation structure 140, the fourth isolation structure 142 and the fifth isolation structure 144 can also be other suitable shapes, such as circular rings or rectangular rings, and the shapes of the first isolation structure 136, the second isolation structure 138, the third isolation structure 140, the fourth isolation structure 142 and the fifth isolation structure 144 can be the same or different from each other. In the embodiments throughout this article, as long as space allows, any one or more of the first isolation structure 136, the second isolation structure 138, the third isolation structure 140, the fourth isolation structure 142 and the fifth isolation structure 144 can be arranged in any embodiment as needed. The first isolation structure 136, the second isolation structure 138, the third isolation structure 140, the fourth isolation structure 142 and the fifth isolation structure 144 can also be in the form of a plurality of isolation blocks spaced apart from each other, and the isolation blocks can be arranged one by one to be adjacent to each light-conducting opening or each photosensitive area.

[0051] Figure 4A FIG. 4 shows a cross-sectional schematic diagram of a photoelectric detection structure 100d according to another embodiment of the present application. FIG. 4B to FIG. 4E They are shown respectively Figure 4A A schematic top view of the second metal wiring layer 124b, the third metal wiring layer 124c, the first metal wiring layer 124a and the photosensitive area 114 is shown. FIG. 4A to FIG. 4E The photodetection structure 100d shown is Figures 1A to 1E The photodetection structure 100a shown is similar, and only the differences are described below. FIG. 4A to FIG. 4EIn the illustrated embodiment, the second plurality of light-conducting openings 130 are interconnected to form an annular opening whose center is partially filled by the second metal wiring layer 124c. The first plurality of light-conducting openings 126 are also interconnected to form an annular opening whose center is partially filled by the first metal wiring layer 124a. Since the first metal wiring layer 124a is farther from the light input opening 128 than the second metal wiring layer 124c, the spacing between the first plurality of light-conducting openings 126 and the central axis is larger than the spacing between the second plurality of light-conducting openings 130 and the central axis. Therefore, compared with the annular opening formed by the second plurality of light-conducting openings 130, the size of the annular opening formed by the first plurality of light-conducting openings 126 is larger than the size of the annular opening formed by the second plurality of light-conducting openings 130.

[0052] exist FIG. 4A to FIG. 4E In the illustrated embodiment, the number of the first plurality of light-conducting openings 126 and the number of the second plurality of light-conducting openings 130 are eight, i.e., eight inclined light paths are formed. The projections of the eight inclined light signals on the second metal wiring layer 124b may extend along directions of 0°, 45°, 90°, 135°, 180°, 225°, 270°, and 315°, respectively. When there are many light paths and the incident angle between two adjacent light paths is relatively small, the incident angle between two adjacent light paths is relatively small, which may cause the light-conducting openings in some metal wiring layers near the light input opening 128 to be connected or even overlapped, for example Figure 4B The second plurality of light-conducting openings 130 shown overlap to form an annular opening, for example Figure 4C The first plurality of light conducting openings 126 are shown connected to form a larger annular opening. In other embodiments, when the incident angle between two adjacent light paths is relatively large, the light conducting openings in the same layer can be spaced apart from each other, for example FIG. 4B to FIG. 4E As shown, the second plurality of light conducting openings 130 are spaced apart from one another, and the first plurality of light conducting openings 128 are spaced apart from one another.

[0053] Further in FIG. 4A to FIG. 4E In the illustrated embodiment, the light input opening 128 may be octagonal, while the first plurality of light transmission openings 126, the second plurality of light transmission openings 130, and the plurality of photosensitive regions 114 may be rectangular in shape. The light input opening 128, the first plurality of light transmission openings 126, the second plurality of light transmission openings 130, and the plurality of photosensitive regions 114 may be any other suitable shapes.

[0054] Figure 5A FIG. 4 shows a cross-sectional schematic diagram of a photoelectric detection structure 100e according to another embodiment of the present application. FIG. 5B to FIG. 5E They are shown respectively Figure 5AA schematic top view showing the relative positions of the second metal wiring layer 124b, the third metal wiring layer 124c, the first metal wiring layer 124a, and the photosensitive region 114 and the isolation structure. FIG. 5A to FIG. 5E The photodetection structure 100e shown is FIG. 4A to FIG. 4E The photodetection structure 100d shown is similar, and only the differences are described below. FIG. 5A to FIG. 5E In the illustrated embodiment, the photodetection structure 100e includes a first isolation structure 136 and a second isolation structure 138 respectively located in the first interlayer dielectric layer and the second interlayer dielectric layer. FIG. 2A to FIG. 2E The first isolation structure 136 and the second isolation structure 138 described are similar, and the only difference is that the first isolation structure 136 and the second isolation structure 138 in the photodetection structure 100e are shaped as continuous octagonal rings.

[0055] Fig. 6A FIG. 4 shows a cross-sectional schematic diagram of a photoelectric detection structure 100 f according to another embodiment of the present application. FIG. 6B to FIG. 6E They are shown respectively Fig. 6A A schematic top view showing the relative positions of the second metal wiring layer 124b, the third metal wiring layer 124c, the first metal wiring layer 124a, and the photosensitive region 114 and the isolation structure. FIG. 6A to FIG. 6E The photodetection structure 100f shown is FIG. 5A to FIG. 5E The photoelectric detection structure 100e shown is similar, and only the differences are described below. FIG. 6A to FIG. 6E In the illustrated embodiment, the photodetection structure 100f includes a third isolation structure 140 and a fourth isolation structure 142 respectively located in the first interlayer dielectric layer and the second interlayer dielectric layer. FIG. 3A to FIG. 3E The third isolation structure 140 and the fourth isolation structure 142 described are similar, and the only difference is that the third isolation structure 140 and the fourth isolation structure 142 in the photodetection structure 100f are in the shape of continuous octagons.

[0056] Fig. 7A FIG. 4 shows a cross-sectional schematic diagram of a photoelectric detection structure 100g according to another embodiment of the present application. FIG. 7B to FIG. 7E They are shown respectively Fig. 7A A schematic top view of the second metal wiring layer 124b, the third metal wiring layer 124c, the first metal wiring layer 124a and the photosensitive area 114 is shown. 7A to 7E The photodetection structure 100g shown is Figures 1A to 1D The photodetection structure 100a shown is similar, and only the differences are described below. 7A to 7EIn the illustrated embodiment, the light input opening 128 of the photoelectric detection structure 100g is circular, and the first plurality of light conducting openings 126, the second plurality of light conducting openings 130 and the photosensitive region 114 are all fan-shaped rings. Since the cross section (or cross section) of the optical fiber transmitting the optical signal is circular or elliptical, the light input opening 128 can completely transmit the optical signal from the optical fiber when it is a circular opening.

[0057] Fig. 8A FIG. 4 shows a cross-sectional schematic diagram of a photoelectric detection structure 100h according to another embodiment of the present application. FIG. 8B to FIG. 8E They are shown respectively Fig. 8A A schematic top view showing the relative positions of the second metal wiring layer 124b, the third metal wiring layer 124c, the first metal wiring layer 124a, and the photosensitive region 114 and the isolation structure. FIG. 8A to FIG. 8E The photodetection structure 100h shown is 7A to 7E The photoelectric detection structure 100g shown is similar, and only the differences are described below. FIG. 8A to FIG. 8E In the illustrated embodiment, the photodetection structure 100h includes a first isolation structure 136 and a second isolation structure 138 located in the first interlayer dielectric layer and the second interlayer dielectric layer. FIG. 2A to FIG. 2E The first isolation structure 136 and the second isolation structure 138 described are similar, and the only difference is that the first isolation structure 136 and the second isolation structure 138 in the photodetection structure 100e are shaped as continuous circular rings.

[0058] Fig. 9A FIG. 4 shows a cross-sectional schematic diagram of a photoelectric detection structure 100i according to another embodiment of the present application. FIG. 9B to FIG. 9E They are shown respectively Fig. 9A A schematic top view showing the relative positions of the second metal wiring layer 124b, the third metal wiring layer 124c, the first metal wiring layer 124a, and the photosensitive region 114 and the isolation structure. 9A to 9E The photodetection structure 100i shown is FIG. 8A to FIG. 8E The photoelectric detection structure 100h shown is similar, and only the differences are described below. 9A to 9E In the illustrated embodiment, the photodetection structure 100i includes a third isolation structure 140 and a fourth isolation structure 142 located in the first interlayer dielectric layer and the second interlayer dielectric layer. The third isolation structure 140 and the fourth isolation structure 142 in the photodetection structure 100i are similar to those in the embodiment of FIG. FIG. 3A to FIG. 3E The third isolation structure 140 and the fourth isolation structure 142 described are similar, and the only difference is that the third isolation structure 140 and the fourth isolation structure 142 in the photodetection structure 100i are in the shape of continuous circular rings.

[0059] Fig. 10A FIG. 4 shows a cross-sectional schematic diagram of a photodetection structure 100j according to another embodiment of the present application. FIG. 10B to FIG. 10E They are shown respectively Fig. 10A A schematic top view showing the relative positions of the second metal wiring layer 124b, the third metal wiring layer 124c, the first metal wiring layer 124a, and the photosensitive region 114 and the isolation structure. FIG. 10A to FIG. 10E The photodetection structure 100j shown is FIG. 8A to FIG. 8E The photoelectric detection structure 100h shown is similar, and only the differences are described below. FIG. 10A to FIG. 10E In the illustrated embodiment, the first isolation structure 136 and the second isolation structure 138 in the photoelectric detection structure 100j are respectively a plurality of isolation blocks arranged at intervals, and the shape of the isolation blocks may be a trapezoid. The number of isolation blocks in the first isolation structure 136 corresponds one-to-one to the number of the plurality of photosensitive regions 114, and in the top view, each isolation block is arranged inside a corresponding photosensitive region, and the length of the isolation block is greater than the arc length of the outer diameter of the fan-shaped ring of the photosensitive region 114, so as to minimize the mutual interference between the corresponding light path and the adjacent light path. Similarly, the number of isolation blocks in the second isolation structure 138 corresponds one-to-one to the number of the first plurality of light-conducting openings 126, and in the top view, each isolation block is arranged inside a corresponding light-conducting opening, so as to reduce the mutual interference between the corresponding light path and the adjacent light path.

[0060] Despite Fig. 10C and Fig. 10D The shape of the isolation block is shown as a trapezoid, but the shape of the isolation block can be any suitable shape. FIG. 11A to FIG. 11C The isolation blocks shown are respectively a fan-shaped ring with the fan center (the center of the fan-shaped ring) on ​​the outside, a rectangle, and a fan-shaped ring with the fan center on the inside. When the isolation block is in the shape of a fan-shaped ring, the arc length of the outer diameter of the fan-shaped ring of the isolation block is greater than the arc length of the outer diameter of the fan-shaped ring of the photosensitive area 114, so as to minimize the mutual interference between the corresponding light path and the adjacent light path. When the lengths of the isolation blocks are the same, generally speaking, the fan-shaped ring isolation block with the fan center on the outside has the best effect, followed by the rectangular ring isolation block, and then the fan-shaped ring isolation block with the fan center on the inside. However, the present application is not limited to this, as long as the shape of the isolation block can play the role of enclosing, semi-enclosing, partially enclosing, or partially blocking the corresponding light path.

[0061] Fig. 12A FIG. 4 shows a cross-sectional schematic diagram of a photoelectric detection structure 100k according to another embodiment of the present application. FIG. 12B to FIG. 12E They are shown respectively Fig. 12A A schematic top view of the second metal wiring layer 124b, the third metal wiring layer 124c, the first metal wiring layer 124a and the photosensitive area 114 is shown. FIG. 12A to FIG. 12EThe photodetection structure 100k shown is 7A to 7E The photoelectric detection structure 100g shown is similar, and only the differences are described below. FIG. 12A to FIG. 12E In the illustrated embodiment, eight inclined light paths are shown, i.e., the number of the plurality of photosensitive areas 114, the first plurality of light-conducting openings 126, and the second plurality of light-conducting openings 130 are all eight. Taking the first plurality of light-conducting openings 126 as an example, the projection of the central axis on the first metal wiring layer 124a is taken as the first circle center, and the first plurality of light-conducting openings 126 are distributed in four different directions with the first circle center as the center, i.e., there are two light-conducting openings 126 in each direction, and for the light-conducting openings 126 in the same direction, the closer to the central axis, the smaller the size of the light-conducting openings 126. The distribution direction of the plurality of photosensitive areas 114 and the second plurality of light-conducting openings 130 is the same as that of the first plurality of light-conducting openings 126, but the distances from the central axis are different. Although the figure shows only four directions and only two light-conducting openings 126 (light-conducting openings 130 or photosensitive areas 114) are arranged in each direction, it is understandable that more directions (e.g., eight directions below) can be arranged and more light-conducting openings 126 (light-conducting openings 130 or photosensitive areas 114) can be arranged in each direction. In addition, when the light signal incident on two light-conducting openings 130 located in the same direction is at a small angle, it will cause the second plurality of light-conducting openings 130 located in the same direction to connect or merge, for example Fig. 12C shown.

[0062] Fig.13A FIG. 4 shows a cross-sectional schematic diagram of a photoelectric detection structure 1001 according to another embodiment of the present application. FIG. 13B to FIG. 13E They are shown respectively Fig.13A A schematic top view of the second metal wiring layer 124b, the third metal wiring layer 124c, the first metal wiring layer 124a and the photosensitive area 114 is shown. FIG. 13A to FIG. 13E The photodetection structure 1001 shown is FIG. 12A to FIG. 12E The photoelectric detection structure 100k shown is similar, and only the differences are described below. FIG. 13A to FIG. 13EIn the illustrated embodiment, the first plurality of light-conducting openings 126 are distributed in eight different directions with the first center of the circle as the center, and the distances between the light-conducting openings 126 in different directions and the first center of the circle are the same. For example, there is one light-conducting opening 126 in each of the eight directions of 0°, 45°, 90°, 135°, 180°, 225°, 270°, and 315°. The distribution of the plurality of photosensitive areas 114 and the second plurality of light-conducting openings 130 is similar to the distribution of the first plurality of light-conducting openings 126. However, the distances between two adjacent light-conducting openings 126 (or light-conducting openings 130, a plurality of photosensitive areas 114) in the eight different directions and the central axis may be different from each other, such as FIG. 14A to FIG. 14E The photoelectric detection structure is shown in 100m.

[0063] Fig.15A FIG. 4 shows a cross-sectional schematic diagram of a photoelectric detection structure 100n according to another embodiment of the present application. FIG. 15B to FIG. 15E They are shown respectively Fig.15A A schematic top view of the second metal wiring layer 124b, the third metal wiring layer 124c, the first metal wiring layer 124a and the photosensitive area 114 is shown. FIG. 15A to FIG. 15E The photodetection structure 100n shown is FIG. 13A to FIG. 13E The photoelectric detection structure 1001 shown is similar, and only the differences are described below. FIG. 15A to FIG. 15E In the illustrated embodiment, sixteen inclined light paths are shown, i.e., the number of the first plurality of light-conducting openings 126 and the number of the second plurality of light-conducting openings 130 are both sixteen. Taking the first plurality of light-conducting openings 126 as an example, the projection of the central axis on the first metal wiring layer 124a is taken as the first circle center, and the first plurality of light-conducting openings 126 are distributed in eight different directions with the first circle center as the center, i.e., there are two light-conducting openings 126 in each direction, and for the light-conducting openings 126 in the same direction, the closer to the central axis, the smaller the size of the light-conducting openings 126. The distribution of the plurality of photosensitive regions 114 and the second plurality of light-conducting openings 130 is similar to that of the first plurality of light-conducting openings 126, except that the distances from the central axis are different.

[0064] Fig.16A FIG. 4 shows a cross-sectional schematic diagram of a photoelectric detection structure 100p according to another embodiment of the present application. FIG. 16B to FIG. 16E They are shown respectively Fig.16A A schematic top view showing the relative positions of the second metal wiring layer 124b, the third metal wiring layer 124c, the first metal wiring layer 124a, and the photosensitive region 114 and the isolation structure. FIG. 16A to FIG. 16E The photodetection structure 100p shown is FIG. 12A to FIG. 12EThe photoelectric detection structure 100k shown is similar, and only the differences are described below. FIG. 16A to FIG. 16E In the illustrated embodiment, in the top view, a sixth isolation structure 146 located in the first interlayer dielectric layer is arranged between two photosensitive regions 114 in the same direction, the sixth isolation structure 146 includes a plurality of isolation blocks, the plurality of isolation blocks are located one-to-one between the two photosensitive regions 114 in the same direction, and the first isolation structure 136 in the form of isolation blocks includes isolation columns located one-to-one inside the four inner photosensitive regions. Similarly, in the top view, a seventh isolation structure 148 located in the second interlayer dielectric layer is arranged between two light-conducting openings 126 in the same direction, the seventh isolation structure 148 includes a plurality of isolation blocks, the plurality of isolation blocks are located one-to-one between the two light-conducting openings 126, and the second isolation structure 138 in the form of isolation blocks is an isolation column located inside the four inner light-conducting openings 126.

[0065] Fig.17A FIG. 4 shows a cross-sectional schematic diagram of a photodetection structure 100q according to another embodiment of the present application. FIG. 17B to FIG. 17E They are shown respectively Fig.17A A schematic top view of the second metal wiring layer 124b, the third metal wiring layer 124c, the first metal wiring layer 124a and the photosensitive area 114 is shown. FIG. 17A to FIG. 17E The photodetection structure 100q shown is FIG. 16A to FIG. 16E The photodetection structure 100n shown is similar, and only the differences are described below. FIG. 17A to FIG. 17E In the illustrated embodiment, the photodetection structure 100q further includes a third isolation structure 140, a fourth isolation structure 142, and a fifth isolation structure 144. In the top view, the third isolation structure 140, the fourth isolation structure 142, and the fifth isolation structure 144 are all shaped as continuous circular rings respectively located outside all photosensitive regions 114, all first light-conducting openings 126, and all second light-conducting openings 128. In addition, the first isolation structure 136 may also be shaped as a continuous circular ring.

[0066] Fig.18A FIG. 4 shows a cross-sectional schematic diagram of a photoelectric detection structure 100r according to another embodiment of the present application. FIG. 18B to FIG. 18E They are shown respectively Fig.18A A schematic top view of the second metal wiring layer 124b, the third metal wiring layer 124c, the first metal wiring layer 124a and the photosensitive area 114 is shown. FIG. 18A to FIG. 18E The photodetection structure 100r shown is FIG. 12A to FIG. 12EThe photoelectric detection structure 100k shown is similar, and only the differences are described below. In the top view, isolation structures are provided outside the photosensitive area 114 and the light-conducting opening 126 in the same direction, and a separate isolation structure is provided outside all the light-conducting openings 130. Since the second metal wiring layer 124c is closer to the light input opening than the first metal wiring layer 124a, the eight light-conducting openings are closer to each other, so it is difficult to form an isolation structure inside them. Therefore, a separate isolation structure can be provided outside all the light-conducting openings 130 to prevent interference from external light.

[0067] In the photoelectric detection structure provided in the embodiment of the present application, by forming a light-guiding structure with an inclined optical path above a plurality of photosensitive areas, a plurality of optical fibers can be arranged obliquely around the light input opening above the light input opening, without the need to be arranged transversely spaced apart perpendicularly to the photoelectric detection structure as in the prior art, so that multiple light rays from a plurality of optical fibers can be input into the light-guiding structure from a single light input opening, and respectively transmitted to a plurality of photosensitive areas through a plurality of inclined optical paths, so that the arrangement of a plurality of photosensitive areas is no longer limited by the thickness of the optical fiber core layer, but can be arranged closer, thereby increasing the number of photosensitive areas per unit area. Accordingly, the volume of the photoelectric detection structure is significantly reduced. In the case of having the same number of photosensitive areas, the volume of the photoelectric detection structure provided by the present application is also smaller than that of the prior art, and accordingly, the cost is further reduced. In addition, as the number of photosensitive areas in the photoelectric detection structure increases, an isolation structure can be provided in the interlayer dielectric layer above the photosensitive area and the inner side of the light transmission opening to prevent interference between the target light path and other light paths.

[0068] It should be understood that the various features of the various embodiments of the present application can be replaced and combined. The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any combination of the various embodiments within the spirit and principle of the present application, as well as any modification, equivalent replacement, improvement, etc. made to the embodiments, shall be included in the protection scope of the present application.

Claims

1. A photoelectric detection structure, characterized in that: include: substrate; A plurality of photosensitive regions are located on the substrate; as well as A light guide structure is located above the plurality of photosensitive areas, and the light guide structure comprises: a plurality of interlayer dielectric layers located on the photosensitive region; and A plurality of metal wiring layers, alternately stacked with the plurality of interlayer dielectric layers, the plurality of metal wiring layers at least comprising a first metal wiring layer and a second metal wiring layer located above the first metal wiring layer; Wherein, the second metal wiring layer includes a light input opening, and the first metal wiring layer includes a first plurality of light conduction openings, wherein, in a top view, the first plurality of light conduction openings are arranged around the light input opening to form a plurality of inclined optical paths for respectively conducting multiple optical signals to the plurality of photosensitive areas.

2. The photoelectric detection structure according to claim 1, characterized in that: The multiple metal wiring layers also include a third metal wiring layer located between the first metal wiring layer and the second metal wiring layer, and the third metal wiring layer includes a second plurality of light-conducting openings. In a top view, the second plurality of light-conducting openings surround the light input openings to form part of the multiple inclined optical paths.

3. The photoelectric detection structure according to claim 2, characterized in that: In a top view, the first plurality of light-conducting openings are arranged to surround the second plurality of light-conducting openings, and the plurality of photosensitive regions are disposed to surround the first plurality of light-conducting openings.

4. The photoelectric detection structure according to claim 3, characterized in that: The second plurality of light-conducting openings are connected to each other to form a ring-shaped opening whose center is filled with a portion of the second metal wiring layer.

5. The photoelectric detection structure according to claim 4, characterized in that: The first plurality of light-conducting openings are connected to each other to form a ring-shaped opening whose center is filled with a portion of the first metal wiring layer.

6. The photoelectric detection structure according to claim 3, characterized in that: The second plurality of light conducting openings are spaced apart from one another, and the first plurality of light conducting openings are spaced apart from one another.

7. The photoelectric detection structure according to claim 2, characterized in that: It also includes a first isolation structure located in the first interlayer dielectric layer between the photosensitive area and the first metal wiring layer. In a top view, the first isolation structure is located between the multiple photosensitive areas and the light input opening.

8. The photoelectric detection structure according to claim 7, characterized in that: It also includes a second isolation structure located in the second interlayer dielectric layer between the first metal wiring layer and the third metal wiring layer. In a top view, the second isolation structure is located between the first plurality of light-conducting openings and the light input openings.

9. The photoelectric detection structure according to claim 8, characterized in that: The first isolation structure and the second isolation structure are in a continuous ring shape or are a plurality of isolation blocks that are spaced apart from each other.

10. The photoelectric detection structure according to claim 2, characterized in that: It also includes a third isolation structure located in the first interlayer dielectric layer between the multiple photosensitive regions and the first metal wiring layer. In the top view, the third isolation structure is located on the outside of the multiple photosensitive regions away from the light input opening and surrounds the multiple photosensitive regions.

11. The photoelectric detection structure according to claim 10, characterized in that: It also includes a fourth isolation structure, which is located in the second interlayer dielectric layer between the first metal wiring layer and the third metal wiring layer. In the top view, the fourth isolation structure is located on the outside of the first plurality of light-conducting openings away from the light input openings and surrounds the first plurality of light-conducting openings.

12. The photoelectric detection structure according to any one of claims 1 to 11, characterized in that: Also included is an insulating layer located above the light guiding structure.

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