Photoelectric sensor and its manufacturing method

Abstract

This invention relates to a photoelectric sensor and its manufacturing method. The photoelectric sensor includes: a substrate; a leg layer located above the substrate, including a first leg; a first support column for supporting the leg layer; a leg-bridge surface hybrid layer located above the leg layer, including a first bridge surface and a second leg, the second leg being electrically connected to the first bridge surface; a second support column for supporting the leg-bridge surface hybrid layer; a bridge surface layer located above the leg-bridge surface hybrid layer, including a second bridge surface; and a third support column for supporting the bridge surface layer, a portion of the third support column being located directly above the first bridge surface. This invention adds a leg-bridge surface hybrid layer, thus providing a larger area for the legs, accommodating longer legs to match smaller legs (CD), thereby achieving better product performance. The bridge surface is located in the top bridge surface layer and the leg-bridge surface hybrid layer, also providing a larger area for thermistor material, which also helps improve product performance.

Description

Technical Field

[0001] This invention relates to micro-motor systems, and more particularly to a photoelectric sensor, and also to a method for manufacturing the photoelectric sensor. Background Technology

[0002] An exemplary MEMS (Micro-Electro-Mechanical Systems) photoelectric sensor has a two-layer structure located above a substrate: a leg layer and a bridge surface layer. As pixel size shrinks, the critical dimension (CD) of the leg decreases, requiring a corresponding increase in leg length to meet performance standards. However, there are limits to the increase in leg length within a limited pixel area; it may be possible to fill the entire area of ​​the leg layer with the legs and still not meet performance requirements. Summary of the Invention

[0003] Therefore, it is necessary to provide a photoelectric sensor and its manufacturing method that can improve product performance.

[0004] A photoelectric sensor includes: a substrate including a readout circuit; a leg layer located above the substrate and including a first leg; a first support post connected to the substrate at its bottom and to the leg layer at its top, for supporting the leg layer; a first conductive structure located on the first support post and electrically connected to the readout circuit and the first leg; a leg-bridge surface hybrid layer located above the leg layer, including a first bridge surface and a second leg, the first bridge surface including a thermistor material, and the second leg electrically connected to the first bridge surface; and a second support post connected to the leg layer at its bottom and to the first support post at its top. A bridge leg and bridge deck hybrid layer for supporting the bridge leg and bridge deck hybrid layer; a second conductive structure located on the second support column and electrically connected to the first bridge leg and the second bridge leg; a bridge deck layer located above the bridge leg and bridge deck hybrid layer, including a second bridge deck, the second bridge deck including a thermistor material; a third support column connected to the bridge leg and bridge deck hybrid layer at the bottom and connected to the bridge deck layer at the top, for supporting the bridge deck layer, a portion of the third support column being located directly above the first bridge deck; a third conductive structure located on the third support column and electrically connected to the first bridge deck and the second bridge deck.

[0005] The aforementioned photoelectric sensor, in addition to the bridge leg layer, also features a bridge leg-bridge surface hybrid layer. This provides a larger area for the bridge legs, allowing for longer legs to match the smaller bridge legs (CD), thus resulting in better product performance. The bridge surface, located within the top bridge surface layer and the bridge leg-bridge surface hybrid layer, also provides a larger area for thermistor material, further enhancing product performance. The area of ​​the first bridge surface is reused to house a portion of the third support column, further expanding the bridge surface installation area.

[0006] In one embodiment, the first bridge leg includes an upper protective layer, a metal layer, and a lower protective layer, wherein the metal layer is located between the upper and lower protective layers.

[0007] In one embodiment, the second bridge leg includes an upper protective layer, a metal layer, and a lower protective layer, wherein the metal layer is located between the upper and lower protective layers.

[0008] In one embodiment, the upper protective layer of the first bridge leg is made of silicon nitride, the metal layer of the first bridge leg is made of titanium, and the lower protective layer of the first bridge leg is made of silicon nitride.

[0009] In one embodiment, the upper protective layer of the second bridge leg is made of silicon nitride, the metal layer of the second bridge leg is made of titanium, and the lower protective layer of the second bridge leg is made of silicon nitride.

[0010] In one embodiment, the bridge leg and bridge deck hybrid layer further includes a bridge deck metal connection wire electrically connected to the first bridge deck, and one side of the second bridge leg metal layer is electrically connected to the bridge deck metal connection wire and the other side is electrically connected to the second conductive structure.

[0011] In one embodiment, the third support column is located between the first bridge deck and the second bridge deck.

[0012] In one embodiment, the photoelectric sensor further includes: a first protective layer located on the upper surface of the third conductive structure; and a second protective layer located between the thermistor material of the first bridge surface and the third conductive structure.

[0013] A method for manufacturing a photoelectric sensor includes: forming a first sacrificial layer, a first support pillar, a first conductive structure, and a bridge leg layer on a substrate having a readout circuit; the bridge leg layer is located on the upper surface of the first sacrificial layer, the bridge leg layer includes a first bridge leg, the bottom of the first support pillar is connected to the substrate, and the top of the first support pillar is connected to the bridge leg layer, the first conductive structure on the first support pillar is electrically connected to the readout circuit and the first bridge leg; forming a second sacrificial layer, a second support pillar, a second conductive structure, and a bridge leg / bridge surface hybrid layer on the bridge leg layer; the bridge leg / bridge surface hybrid layer includes a first bridge surface and a second bridge leg, the first bridge surface includes a thermistor material, the second bridge leg is electrically connected to the first bridge surface, the bottom of the second support pillar is connected to the bridge leg layer, and the top of the second support pillar is connected to the bridge leg / bridge surface hybrid layer. A composite layer is formed, and a second conductive structure on the second support post is electrically connected to the first bridge leg and the second bridge leg; a third sacrificial layer is formed on the bridge leg deck composite layer, and at least a portion of the first bridge surface is not covered by the third sacrificial layer, thereby forming a first through-hole in the third sacrificial layer; a third support post is formed at the location of the first through-hole, the bottom of the third support post is connected to the bridge leg deck composite layer, and the top extends to the upper surface of the third sacrificial layer; a second bridge surface is formed on the third sacrificial layer and connected to the third support post, the second bridge surface including a thermistor material; a third conductive structure is formed on the third support post, the third conductive structure being electrically connected to the first bridge surface and the second bridge surface; the first sacrificial layer, the second sacrificial layer, and the third sacrificial layer are released.

[0014] The aforementioned manufacturing method for the photoelectric sensor thickens the metal layer in the bridge area. This avoids the difficulty in mass production caused by an excessively thin first metal layer in the bridge area, which would result in a small process window (the thin first metal layer is easily etched through) when forming the through-hole that penetrates the second protective layer. This allows the first metal layer to be made very thin, reducing heat loss during heat conduction and thus improving product performance. Furthermore, the thickened metal layer in the bridge area is formed using a photolithography-following vapor deposition process, which does not affect the uniformity of the film layer in the bridge area. This reduces the impact of the metal thickening process on the product, lowers the possibility of new anomalies caused by the metal thickening process, and does not affect the location of the bridge area, which determines product performance.

[0015] In one embodiment, the step of forming a first sacrificial layer, a first support pillar, a first conductive structure, and a bridge leg layer on a substrate on which a readout circuit is formed includes: forming a first sacrificial layer having a second through-hole on the substrate; forming the first support pillar at the location of the second through-hole; and forming the first conductive structure and the bridge leg layer on the first sacrificial layer. The step of forming a second sacrificial layer, a second support pillar, a second conductive structure, and a bridge leg / bridge surface hybrid layer on the bridge leg layer includes: forming a second sacrificial layer having a third through-hole on the bridge leg layer; forming the second support pillar at the location of the third through-hole; forming the first bridge surface on the upper surface of the second support pillar; and forming the second conductive structure and the second bridge leg on the second sacrificial layer.

[0016] In one embodiment, the step of forming the second conductive structure and the second leg on the second sacrificial layer includes: forming a first metal layer, the first metal layer including a second leg metal layer, a second conductive structure and a bridge deck metal interconnect, the bridge deck metal interconnect being electrically connected to the first bridge deck, one side of the second leg metal layer being electrically connected to the bridge deck metal interconnect and the other side being electrically connected to the second conductive structure; and forming a first protective layer covering the first metal layer.

[0017] In one embodiment, the step of forming a third conductive structure on the third support post includes: etching the third support post and the first protective layer in the first through hole to expose the bridge deck metal connection in the first through hole; forming a third conductive structure, wherein one side of the third conductive structure is electrically connected to the bridge deck metal connection and the other side is electrically connected to the second bridge deck. Attached Figure Description

[0018] To better describe and illustrate embodiments and / or examples of the inventions disclosed herein, reference may be made to one or more accompanying drawings. Additional details or examples used to describe the drawings should not be considered as limiting the scope of any of the disclosed inventions, the currently described embodiments and / or examples, or the best mode of these inventions as currently understood.

[0019] Figure 1 This is a top view of an exemplary bridge leg.

[0020] Figure 2 This is a schematic diagram of the structure of a photoelectric sensor in one embodiment of this application.

[0021] Figure 3 This is a flowchart of a method for manufacturing a photoelectric sensor according to one embodiment of this application.

[0022] Figures 4a-4g Is adopted Figure 3The diagram shows a cross-sectional view of the photoelectric sensor during the manufacturing process.

[0023] Figure 5 This is a flowchart of a sub-step of step S310 in one embodiment of this application.

[0024] Figure 6 This is a flowchart of a sub-step of step S320 in one embodiment of this application. Detailed Implementation

[0025] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

[0026] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0027] It should be understood that when an element or layer is referred to as "on," "adjacent to," "connected to," or "coupled to" other elements or layers, it may be directly on, adjacent to, connected to, or coupled to other elements or layers, or there may be intervening elements or layers. Conversely, when an element is referred to as "directly on," "directly adjacent to," "directly connected to," or "directly coupled to" other elements or layers, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc., may be used to describe various elements, components, areas, layers, and / or portions, these elements, components, areas, layers, and / or portions should not be limited by these terms. These terms are only used to distinguish one element, component, area, layer, or portion from another element, component, area, layer, or portion. Therefore, without departing from the teachings of this invention, the first element, component, area, layer, or portion discussed below may be referred to as the second element, component, area, layer, or portion.

[0028] Spatial relation terms such as “below,” “under,” “below,” “under,” “above,” “above,” etc., are used herein for convenience of description to describe the relationship between one element or feature shown in the figure and other elements or features. It should be understood that, in addition to the orientation shown in the figure, spatial relation terms are intended to also include different orientations of the device in use and operation. For example, if the device in the figure is flipped, then the element or feature described as “below” or “under” the other element or feature will be oriented “above” the other element or feature. Therefore, the exemplary terms “below” and “under” can include both upper and lower orientations. The device may be otherwise oriented (rotated 90 degrees or otherwise) and the spatial descriptive terms used herein will be interpreted accordingly.

[0029] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. When used herein, the singular forms “a,” “an,” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising” and / or “including,” when used in this specification, identify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. When used herein, the term “and / or” includes any and all combinations of the associated listed items.

[0030] Embodiments of the invention are described herein with reference to cross-sectional views that serve as schematic diagrams of ideal embodiments (and intermediate structures). Thus, variations in the shape shown can be anticipated due to, for example, manufacturing techniques and / or tolerances. Therefore, embodiments of the invention should not be limited to the specific shapes of the regions shown herein, but include shape deviations due to, for example, manufacturing processes. For example, implantation regions shown as rectangular typically have rounded or curved features at their edges and / or implantation concentration gradients, rather than a binary change from implantation regions to non-implantation regions. Similarly, the buried regions formed by implantation can result in some implantation in the region between the buried region and the surface traversed during implantation. Therefore, the regions shown in the figures are substantially schematic, and their shapes are not intended to show the actual shapes of the regions of the device and are not intended to limit the scope of the invention.

[0031] In MEMS optoelectronic sensors, the legs serve both electrical connection and heat conduction. An exemplary leg structure is a sandwich structure of a protective layer-metal layer-protective layer. Taking a silicon nitride-titanium-silicon nitride structure as an example, if the leg's CD (which can be the leg's width) is too large, the silicon nitride will dissipate heat excessively, leading to a decrease in sensor performance. If CD is too small, and the leg length remains constant, the titanium's response time will not meet design requirements. Therefore, considering both heat conduction and response time, the leg's CD and length must be matched. Properly adjusting the matching of the leg's CD and length can improve sensor performance.

[0032] To achieve sufficient leg length within a limited pixel area, the legs can be designed as a bent structure, see [reference needed]. Figure 1 . Figure 1 The middle bridge leg 30 is connected to the electrode 40, and W is the width of the bridge leg 30.

[0033] An exemplary 8-inch wafer photoelectric sensor product has a leg layer and a bridge layer above the leg layer. As the pixel size shrinks, the CD of the leg becomes smaller and the length becomes longer, which reduces the strength of the leg and the stability of supporting the second layer.

[0034] This application proposes a MEMS optoelectronic sensor with an innovative structure. Figure 2 This is a schematic diagram of the structure of a photoelectric sensor in one embodiment of this application, including a substrate 110, a leg layer 12, a leg-to-surface hybrid layer 13, a surface layer 14, a first support pillar 111, a first conductive structure 113, a second support pillar 121, a second conductive structure 123, a third support pillar 131, and a third conductive structure 133. Figure 2 The structure shown is symmetrical from left to right, therefore some structures are labeled only on one side. The substrate 110 includes a readout circuit (…). Figure 2(Not shown in the image). In one embodiment of this application, the substrate 110 further includes a metal reflective layer. A bridge leg layer 12 is located above the substrate 110 and includes a first bridge leg 120. A first support post 111 is connected to the substrate 110 at its bottom and to the bridge leg layer 12 at its top, for supporting the bridge leg layer 12. A first conductive structure 113 is located on the first support post 111 and is electrically connected to the readout circuit and the first bridge leg 120. A bridge leg-bridge surface hybrid layer 13 is located above the bridge leg layer 12 and includes a first bridge surface 138 and a second bridge leg 130. The first bridge surface 138 is made of a thermistor material, and the second bridge leg 130 is electrically connected to the first bridge surface 138. A second support post 121 is connected to the bridge leg layer 12 at its bottom and to the bridge leg-bridge surface hybrid layer 13 at its top, for supporting the bridge leg-bridge surface hybrid layer 13. A second conductive structure 123 is located on the second support post 121 and is electrically connected to the first bridge leg 120 and the second bridge leg 130. The bridge deck layer 14 is located above the bridge leg deck hybrid layer 13 and includes a second bridge deck 148, which is made of a thermistor material. A third support column 131 connects to the bridge leg deck hybrid layer 13 at its bottom and to the bridge deck layer 14 at its top, supporting the bridge deck layer 14. A portion of the third support column 131 is located directly above the first bridge deck 138. A third conductive structure 133 is located on the third support column 131 and electrically connects the first bridge deck 138 and the second bridge deck 148.

[0035] The aforementioned photoelectric sensor, in addition to the bridge leg layer 12, also includes a bridge leg-bridge surface hybrid layer 13. This provides a larger area for the bridge legs, allowing for longer legs to match the smaller bridge legs CD, thus resulting in better product performance. The bridge surface is located in the top bridge surface layer 14 and the bridge leg-bridge surface hybrid layer 13, also providing a larger area for thermistor material, further enhancing product performance. The area where the first bridge surface 138 is located is reused to house a portion of the third support column 131, resulting in a larger bridge surface area.

[0036] In one embodiment of this application, the first bridge leg 120 includes an upper protective layer 122, a metal layer 124, and a lower protective layer 126, with the metal layer 124 located between the upper and lower protective layers. Further, the upper and lower protective layers 122 and 126 may be made of silicon oxide or silicon nitride, such as silicon nitride. The metal layer 124 may be made of titanium.

[0037] In one embodiment of this application, the second bridge leg 130 includes an upper protective layer 132, a metal layer 134, and a lower protective layer 136, with the metal layer 134 located between the upper and lower protective layers 132. Further, the upper and lower protective layers 132 and 136 can be made of silicon oxide or silicon nitride, such as silicon nitride. The metal layer 134 can be made of titanium.

[0038] In one embodiment of this application, the first support column 111 is made of the same material as the lower protective layer 126 of the first bridge leg. In one embodiment of this application, the second support column 121 is made of the same material as the lower protective layer 136 of the second bridge leg.

[0039] In one embodiment of this application, the bridge leg and bridge deck hybrid layer 13 further includes a bridge deck metal interconnect 135. The bridge deck metal interconnect 135 is electrically connected to the first bridge deck 138, and one side of the second bridge leg metal layer 134 is electrically connected to the bridge deck metal interconnect 135 and the other side is electrically connected to the second conductive structure 123.

[0040] In one embodiment of this application, the third support column 131 is located between the first bridge deck 138 and the second bridge deck 148.

[0041] In one embodiment of this application, the photoelectric sensor further includes a first protective layer 141 and a second protective layer 143. The first protective layer 141 is located on the upper surface of the third conductive structure 133. The second protective layer 143 is located between the thermistor material of the first bridge surface 138 and the third conductive structure 133.

[0042] In one embodiment of this application, the photoelectric sensor further includes an electrode 125. A second conductive structure 123 is electrically connected to a first bridge leg 120 via the electrode 125. One side of the first bridge leg 120 is electrically connected to the electrode 125, and the other side is electrically connected to the first conductive structure 113. A protective layer 122a is also covered on the electrode 125. The protective layer 122a is made of the same material as the protective layer 122 on the first bridge leg and is formed in the same manufacturing step.

[0043] In one embodiment of this application, a protective layer 132a is covered on the second conductive structure 123. The protective layer 132a is made of the same material as the protective layer 132 on the second bridge leg and is formed in the same manufacturing step.

[0044] In one embodiment of this application, the photoelectric sensor further includes a third protective layer 142 covering the third conductive structure 133 and the second bridge surface 148.

[0045] Based on all the above embodiments, after adding the bridge leg and bridge surface hybrid layer 13, the total bridge leg length of the photoelectric sensor increases. Under the same performance requirements, the bridge leg CD will be larger than that of the old structure, greatly reducing the manufacturing difficulty. Moreover, as the pixels continue to shrink, the bridge leg CD of the old structure will reach its limit, and even at the limit of bridge leg CD and bridge leg length, the performance may not meet the requirements. However, the structure of the embodiments of this application can fully meet the requirements. In addition, this structure increases the area of ​​the bridge surface (thermostat material), and thermistor material can be placed in all areas except the dicing channels of the wafer, which will improve the absorption rate of infrared light and improve product performance.

[0046] This application provides a method for manufacturing a photoelectric sensor, which can be used to manufacture the photoelectric sensor described in any of the above embodiments. Figure 3 This is a flowchart of a method for manufacturing a photoelectric sensor according to an embodiment of this application, including the following steps:

[0047] S310, a first sacrificial layer, a first support pillar, a first conductive structure, and a bridge leg layer are formed on the substrate.

[0048] A wafer having a substrate 110 is provided. The substrate 110 includes readout circuitry. Figure 4a (Not shown). The bridge leg layer 12 is located on the upper surface of the first sacrificial layer 192, and the bridge leg layer 12 includes a first bridge leg 120. The bottom of the first support post 111 is connected to the substrate 110, and the top is connected to the bridge leg layer 12. The first conductive structure 113 on the first support post 111 is electrically connected to the readout circuit and the first bridge leg 120. In one embodiment of this application, the substrate 110 also includes a metal reflective layer ( Figure 4a (Not shown in the text).

[0049] See Figure 5 In one embodiment of this application, step S310 includes:

[0050] S312, a first sacrificial layer with a second through hole is formed on the substrate.

[0051] See Figure 4a In one embodiment of this application, step S312 includes coating a first sacrificial layer 192 on the readout circuit and the metal reflective layer, and etching the first sacrificial layer 192 to form a second via 117 for electrical connection.

[0052] S314, a first support column is formed at the location of the second through hole.

[0053] In one embodiment of this application, the material of the first support pillar 111 is the same as that of the first lower protective layer 126 in the first bridge leg 120. In one embodiment of this application, the materials of the first upper protective layer 122 and the first lower protective layer 126 can be silicon oxide or silicon nitride, such as silicon nitride. In one embodiment of this application, a protective layer material can be deposited on the inner surface of the second via 117 and the first sacrificial layer 192. A portion of the protective layer material serves as the first support pillar 111, and the other portion, after etching in step S316, serves as the first lower protective layer 126.

[0054] S316, a first conductive structure and a bridge leg layer are formed on the first sacrificial layer.

[0055] The first bridge leg 120 includes an upper protective layer 122, a metal layer 124, and a lower protective layer 126, with the metal layer 124 located between the upper and lower protective layers 122 and 126. Figure 4a In the illustrated embodiment, the bridge leg layer 12 further includes an electrode 125. The electrode 125 and the first conductive structure 113 are made of the same material as the first bridge leg metal layer 124 (e.g., titanium). The electrode 125, the first conductive structure 113, and the first bridge leg metal layer 124 can be formed by etching after forming a metal layer on the protective layer material. One side of the first bridge leg metal layer 124 is electrically connected to the first conductive structure 113, and the other side is electrically connected to the electrode 125. Before etching, a protective layer needs to be formed on the metal layer. After etching, the remaining protective layer on the electrode 125 is the protective layer 122a, and the remaining protective layer on the first bridge leg metal layer 124 is the first bridge leg upper protective layer 122. After etching to form the first bridge leg 120, step S310 is completed.

[0056] S320, a second sacrificial layer, a second support column, a second conductive structure and a bridge leg deck hybrid layer are formed on the bridge leg layer.

[0057] The bridge leg-bridge deck hybrid layer 13 includes a first bridge deck 138 and a second bridge leg 130. The first bridge deck 138 includes a thermistor material. The second bridge leg 130 is electrically connected to the first bridge deck 138. The bottom of the second support column 121 is connected to the bridge leg layer 12, and the top is connected to the bridge leg-bridge deck hybrid layer 13. The second conductive structure 123 on the second support column 121 is electrically connected to the first bridge leg 120 and the second bridge leg 130.

[0058] See Figure 6 In one embodiment of this application, step S320 includes:

[0059] S322, a second sacrificial layer with a third through hole is formed on the bridge leg layer.

[0060] See Figure 4bA second sacrificial layer 194 is coated on the bridge leg layer 12, and the second sacrificial layer 194 is etched to form a third through-hole 127.

[0061] S324, a second support column is formed at the position of the third through hole.

[0062] In one embodiment of this application, the material of the second support pillar 121 is the same as that of the second lower protective layer 136 in the second bridge leg 130. In one embodiment of this application, the materials of the second upper protective layer 132 and the second lower protective layer 136 can be silicon oxide or silicon nitride, such as silicon nitride. In one embodiment of this application, a protective layer material can be deposited on the inner surface of the third via 127 and the second sacrificial layer 194, with a portion of the protective layer material serving as the second support pillar 121 and a portion serving as the second lower protective layer 136 after etching in step S326.

[0063] S326, a first bridge deck is formed on the upper surface of the second support column.

[0064] The first bridge deck 138 is formed on the protective layer material on the second sacrificial layer 194. Step S326 also includes forming a second protective layer 143 covering the first bridge deck 138. An area needs to be reserved between the first bridge deck 138 and the third through hole 127 to form the second bridge leg 130.

[0065] S328, a second conductive structure and a second bridge leg are formed on the second sacrificial layer.

[0066] The second bridge leg 130 includes an upper protective layer 132, a metal layer 134, and a lower protective layer 136, with the metal layer 134 located between the upper and lower protective layers. Further, the upper and lower protective layers 132 and 136 can be made of silicon oxide or silicon nitride, such as silicon nitride. The metal layer 134 can be made of titanium. The second conductive structure 123 is made of the same material as the metal layer 134. See also... Figure 4c The protective layer 122a on the upper surface of the electrode 125 in the third via 127 is removed to expose the electrode 125, and the second protective layer 143 is etched to form a hole 139 for electrical connection of the corresponding structure. Then, a first metal layer is deposited on the wafer surface as the second leg metal layer 134, the second conductive structure 123, and the bridge metal interconnect 135. The bridge metal interconnect 135 is electrically connected to the first bridge surface 138, and one side of the second leg metal layer 134 is electrically connected to the bridge metal interconnect 135, and the other side is electrically connected to the second conductive structure 123. See also... Figure 4dA protective layer is formed on the deposited metal layer, and then the second bridge leg 130 is etched. The protective layer on the second conductive structure 123 serves as the protective layer 132a, and the protective layer on the metal layer 134 of the second bridge leg serves as the upper protective layer 132 of the second bridge leg. At this point, step S320 is completed.

[0067] S330, a third sacrificial layer and a first through hole are formed on the bridge leg deck mixed layer.

[0068] This ensures that at least a portion of the first bridge deck 138 is not covered by the third sacrificial layer 196, thereby forming a first through-hole 137 in the third sacrificial layer 196. In one embodiment of this application, see [reference needed]. Figure 4e After completing step S320, a third sacrificial layer 196 is coated on the wafer surface, and the third sacrificial layer 196 is etched to form a first via 137.

[0069] S340, a third support column is formed at the location of the first through hole.

[0070] In one embodiment of this application, a protective layer material may be deposited on the inner surface of the first through-hole 137 and the third sacrificial layer 196, with a portion of the protective layer material serving as the third support pillar 131.

[0071] S350, a second bridge deck is formed on the third sacrificial layer and connected to the third support column.

[0072] See Figure 4f A second bridge surface 148 is formed on the protective layer formed in step S340, and then a third protective layer 142 covering the second bridge surface 148 is deposited.

[0073] S360, a third conductive structure is formed on the third support column.

[0074] The protective layer material on the upper surface of the bridge surface metal interconnect 135 in the first through-hole 137 is removed to expose the bridge surface metal interconnect 135. Then, the third protective layer 142 is etched to form a hole exposing the second bridge surface 148, which is used to achieve electrical connection between the second bridge surface 148 and the bridge surface metal interconnect 135. Next, a metal layer is deposited to form a third conductive structure 133, and then a first protective layer 141 covering the third conductive structure 133 is formed on the third conductive structure 133. (Refer to...) Figure 4g The third conductive structure 133 is electrically connected to the bridge surface metal connection 135 on one side and to the second bridge surface 148 on the other side.

[0075] S370, release the first sacrificial layer, the second sacrificial layer, and the third sacrificial layer.

[0076] A release hole is formed to expose the third sacrificial layer 196, and the third sacrificial layer 196, the second sacrificial layer 194, and the first sacrificial layer 192 are released by wet etching. The completed structure can be found in [reference needed]. Figure 2 .

[0077] The aforementioned method for manufacturing photoelectric sensors includes a bridge leg and bridge surface hybrid layer in addition to the bridge leg layer. This provides a larger area for the bridge legs, allowing for longer legs to match smaller bridge legs (CD), thus resulting in better product performance. The bridge surface is located within the top bridge surface layer and the bridge leg and bridge surface hybrid layer, also providing a larger area for thermistor material, further enhancing product performance. The area of ​​the first bridge surface is reused to house a portion of the third support column, further increasing the bridge surface installation area.

[0078] The manufacturing method of the photoelectric sensor in this application is based on the same inventive concept as the photoelectric sensor. For details not specifically described in the manufacturing method of the photoelectric sensor, please refer to the above introduction of the photoelectric sensor.

[0079] It should be understood that although the steps in the flowchart of this application are shown sequentially as indicated by the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowchart of this application may include multiple steps or multiple stages, which are not necessarily completed at the same time, but may be executed at different times, and the execution order of these steps or stages is not necessarily sequential, but may be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0080] In the description of this specification, references to terms such as "some embodiments," "other embodiments," and "ideal embodiments" indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative descriptions of the above terms do not necessarily refer to the same embodiments or examples.

[0081] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features of the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0082] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A photoelectric sensor, characterized in that, include: The substrate, including the readout circuitry; A bridge leg layer, located above the substrate, includes a first bridge leg; The first support column is connected to the base at the bottom and to the bridge leg layer at the top, and is used to support the bridge leg layer; A first conductive structure is located on the first support post and is electrically connected to the readout circuit and the first bridge leg; A bridge leg and bridge deck hybrid layer, located above the bridge leg layer, includes a first bridge deck and a second bridge leg. The first bridge deck includes a thermistor material, and the second bridge leg is electrically connected to the first bridge deck. The second support column is connected to the bridge leg layer at the bottom and to the bridge leg-bridge deck hybrid layer at the top, and is used to support the bridge leg-bridge deck hybrid layer; The second conductive structure is located on the second support column and is electrically connected to the first bridge leg and the second bridge leg; A bridge deck layer, located above the bridge leg deck hybrid layer, includes a second bridge deck, the second bridge deck including a thermistor material; The third support column is connected to the bridge leg and bridge deck composite layer at the bottom and to the bridge deck layer at the top, and is used to support the bridge deck layer. A part of the structure of the third support column is located directly above the first bridge deck. The third conductive structure is located on the third support column and is electrically connected to the first bridge deck and the second bridge deck.

2. The photoelectric sensor according to claim 1, characterized in that, The first bridge leg includes an upper protective layer, a metal layer, and a lower protective layer, wherein the metal layer is located between the upper and lower protective layers; and / or The second bridge leg includes an upper protective layer, a metal layer, and a lower protective layer, with the metal layer located between the upper and lower protective layers.

3. The photoelectric sensor according to claim 1, characterized in that, The upper protective layer of the first bridge leg is made of silicon nitride, the metal layer of the first bridge leg is made of titanium, and the lower protective layer of the first bridge leg is made of silicon nitride; and / or The material of the upper protective layer of the second bridge leg is silicon nitride, the material of the metal layer of the second bridge leg is titanium, and the material of the lower protective layer of the second bridge leg is silicon nitride.

4. The photoelectric sensor according to claim 1, characterized in that, The bridge leg and bridge deck hybrid layer also includes a bridge deck metal connection line, which is electrically connected to the first bridge deck. One side of the second bridge leg metal layer is electrically connected to the bridge deck metal connection line, and the other side is electrically connected to the second conductive structure.

5. The photoelectric sensor according to claim 1, characterized in that, The third support column is located between the first bridge deck and the second bridge deck.

6. The photoelectric sensor according to claim 1, characterized in that, Also includes: The first protective layer is located on the upper surface of the third conductive structure; The second protective layer is located between the thermistor material of the first bridge surface and the third conductive structure.

7. A method for manufacturing a photoelectric sensor, comprising: A first sacrificial layer, a first support pillar, a first conductive structure, and a bridge leg layer are formed on a substrate on which a readout circuit is formed. The bridge leg layer is located on the upper surface of the first sacrificial layer and includes a first bridge leg. The bottom of the first support pillar is connected to the substrate, and the top is connected to the bridge leg layer. The first conductive structure on the first support pillar is electrically connected to the readout circuit and the first bridge leg. A second sacrificial layer, a second support column, a second conductive structure, and a bridge leg-bridge deck hybrid layer are formed on the bridge leg layer; the bridge leg-bridge deck hybrid layer includes a first bridge deck and a second bridge leg, the first bridge deck includes a thermistor material, the second bridge leg is electrically connected to the first bridge deck, the bottom of the second support column is connected to the bridge leg layer, the top of the second support column is connected to the bridge leg-bridge deck hybrid layer, and the second conductive structure on the second support column is electrically connected to the first bridge leg and the second bridge leg; A third sacrificial layer is formed on the bridge leg deck hybrid layer, and at least a portion of the first bridge deck is not covered by the third sacrificial layer, thereby forming a first through-hole in the third sacrificial layer; A third support post is formed at the location of the first through hole, the bottom of the third support post is connected to the bridge leg deck hybrid layer, and the top extends to the upper surface of the third sacrificial layer; A second bridge surface connected to the third support column is formed on the third sacrificial layer, and the second bridge surface includes a thermistor material; A third conductive structure is formed on the third support column, and the third conductive structure is electrically connected to the first bridge surface and the second bridge surface; Release the first sacrificial layer, the second sacrificial layer, and the third sacrificial layer.

8. The method for manufacturing a photoelectric sensor according to claim 7, characterized in that, The step of forming a first sacrificial layer, a first support pillar, a first conductive structure, and a bridge leg layer on a substrate on which a readout circuit is formed includes: A first sacrificial layer having a second through hole is formed on the substrate; The first support column is formed at the location of the second through hole; The first conductive structure and the bridge leg layer are formed on the first sacrificial layer; The step of forming a second sacrificial layer, a second support column, a second conductive structure, and a bridge leg / bridge deck hybrid layer on the bridge leg layer includes: A second sacrificial layer with a third through hole is formed on the bridge leg layer; The second support post is formed at the location of the third through hole; The first bridge deck is formed on the upper surface of the second support column; The second conductive structure and the second bridge leg are formed on the second sacrificial layer.

9. The method for manufacturing a photoelectric sensor according to claim 8, characterized in that, The step of forming the second conductive structure and the second bridge leg on the second sacrificial layer includes: A first metal layer is formed, the first metal layer including a second bridge leg metal layer, a second conductive structure and a bridge deck metal connection line, the bridge deck metal connection line being electrically connected to the first bridge deck, one side of the second bridge leg metal layer being electrically connected to the bridge deck metal connection line and the other side being electrically connected to the second conductive structure; A first protective layer is formed covering the first metal layer.

10. The method for manufacturing a photoelectric sensor according to claim 9, characterized in that, The step of forming the third conductive structure on the third support column includes: Etch the third support post and the first protective layer in the first through hole to expose the bridge metal connection line in the first through hole; A third conductive structure is formed, wherein one side of the third conductive structure is electrically connected to the bridge deck metal connection line and the other side is electrically connected to the second bridge deck.

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