Packaging structure of optical sensor, optical sensor and movable platform

Abstract

This application provides an optical sensor packaging structure, an optical sensor, and a movable platform, relating to the field of sensor packaging technology. The packaging structure includes: a PCB substrate, a sensor chip, a filter glass, a transparent adhesive layer, and a molding compound layer. The filter glass has a beveled edge structure. The first surface of the filter glass is bonded to the upper surface of the sensor chip via the transparent adhesive layer, and the lower surface of the sensor chip is fixed to the upper surface of the PCB substrate, forming an integral structure. The molding compound layer covers the edge area of ​​the integral structure, and the top surface of the molding compound layer is coplanar and flush with the second surface of the filter glass. This application directly solves the failure problem of cracking or breakage caused by stress concentration at the edge of the filter glass from a structural design perspective, thereby comprehensively ensuring the reliability of the optical sensor in extreme environments.

Description

Technical Field

[0001] This application relates to the field of sensor packaging technology, and in particular to a packaging structure for an optical sensor, an optical sensor, and a movable platform. Background Technology

[0002] With the rapid iteration of intelligent driving technology, optical sensors such as LiDAR, Complementary Metal-Oxide-Semiconductor (CMOS) image sensors, and single-photon avalanche diodes have been widely used in advanced driver assistance systems (ADAS) to achieve high-precision environmental perception functions such as target detection and ranging. However, the operating conditions of automotive applications are complex and varied, and these optical sensors must meet stringent automotive-grade reliability standards, such as high and low temperature cycling and temperature shock tests. Among them, the filter glass, as the core component for filtering light signals in optical sensors, directly determines the sensing accuracy of the optical sensor due to its structural stability. If the filter glass fails under complex operating conditions, such as cracking, splitting, or shattering, it will directly lead to optical path distortion, imaging distortion, and even system-level decision-making errors, which can easily cause driving safety hazards. Summary of the Invention

[0003] This application provides an optical sensor packaging structure, an optical sensor, and a movable platform to reduce the risk of failure such as cracking or breaking of the filter glass.

[0004] In a first aspect, this application provides an optical sensor packaging structure, including: a PCB substrate, a sensor chip, a filter glass, a transparent adhesive layer and a molding compound, wherein the filter glass has a sloping edge structure;

[0005] The first surface of the filter glass is bonded to the upper surface of the sensor chip through a transparent adhesive layer, and the lower surface of the sensor chip is fixed to the upper surface of the PCB substrate to form an integral structure.

[0006] The molding layer covers the edge area of ​​the overall structure, and the top surface of the molding layer is coplanar and flush with the second surface of the filter glass.

[0007] In one possible implementation, the edge angle of the ramp edge structure ranges from 60° to 70°.

[0008] In one possible implementation, the glass thickness of the filter glass is 0.5mm-0.6mm.

[0009] In one possible implementation, the glass tensile strength of the filter glass is ≥100MPa.

[0010] In one possible implementation, the coefficient of thermal expansion of the PCB substrate ranges from 12ppm / ℃ to 15ppm / ℃, and the elastic modulus parameter of the PCB substrate ranges from 22000MPa to 24000MPa.

[0011] In one possible implementation, the coefficient of thermal expansion of the transparent adhesive layer ranges from 10 ppm / ℃ to 20 ppm / ℃, and the elastic modulus parameter of the transparent adhesive layer ranges from 10000 MPa to 13000 MPa.

[0012] In one possible implementation, the molding compound is made of a molding compound containing glass fibers or an epoxy molding compound.

[0013] And / or, the molding compound extends upward from the upper surface of the PCB substrate, and the outer wall of the molding compound has a smoothly transitioning slope or arc structure.

[0014] Secondly, this application provides a packaging structure for an optical sensor, including a PCB substrate, a sensor chip, a filter glass, a transparent adhesive layer, and a molding compound layer.

[0015] The first surface of the filter glass is bonded to the upper surface of the sensor chip through a transparent adhesive layer, and the lower surface of the sensor chip is fixed to the upper surface of the PCB substrate to form an integral structure. The molding layer covers the edge area of ​​the integral structure, and the top surface of the molding layer is coplanar and flush with the second surface of the filter glass.

[0016] The coefficient of thermal expansion of the PCB substrate ranges from 12ppm / ℃ to 15ppm / ℃, and the elastic modulus of the PCB substrate ranges from 22000MPa to 24000MPa; and / or, the coefficient of thermal expansion of the transparent adhesive layer ranges from 10ppm / ℃ to 20ppm / ℃, and the elastic modulus of the transparent adhesive layer ranges from 10000MPa to 13000MPa.

[0017] Thirdly, this application provides an optical sensor, including the first aspect and / or the second aspect as described above and / or various possible implementations of the first aspect and / or the second aspect as described above.

[0018] Fourthly, this application provides a mobile platform, including the embodiments described in the third aspect above.

[0019] This application provides an optical sensor packaging structure, an optical sensor, and a movable platform, relating to the field of sensor packaging technology. The packaging structure includes a PCB substrate, a sensor chip, a filter glass, a transparent adhesive layer, and a molding compound layer. The filter glass has a beveled edge structure. The first surface of the filter glass is bonded to the upper surface of the sensor chip via the transparent adhesive layer, and the lower surface of the sensor chip is fixed to the upper surface of the PCB substrate, forming an integral structure. The molding compound layer covers the edge area of ​​the integral structure, and its top surface is coplanar and flush with the second surface of the filter glass. This application solves the cracking problem caused by stress concentration at the edge of the filter glass in existing packaging through optimized beveled edge structure design. The beveled edge structure transforms the stress concentration points in the right-angle region of the traditional stepped structure into a gradient stress distribution along the bevel angle by changing the geometry of the filter glass edge. The optimized bevel angle design creates a continuous curvature in the transition area between the filter glass edge and the molding compound layer, avoiding abrupt stress changes. This design significantly reduces the risk of filter glass cracking or breakage by reducing the local stress peak at the filter glass edge. Furthermore, the curvature radius adaptation design of the ramp edge structure can accommodate the thermal stress differences of different material parameters, further improving the crack resistance of the filter glass in high and low temperature cycling tests. Ultimately, the above solution directly solves the failure problem of cracking or breakage caused by stress concentration at the edge of the filter glass from the structural design level, thereby comprehensively ensuring the reliability of optical sensors in extreme environments. Attached Figure Description

[0020] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0021] Figure 1 A schematic diagram of the existing optical sensor packaging structure provided in this application Figure 1 ;

[0022] Figure 2 A schematic diagram of the existing optical sensor packaging structure provided in this application Figure 2 ;

[0023] Figure 3 A schematic diagram of the existing optical sensor packaging structure provided in this application Figure 3 ;

[0024] Figure 4 A schematic diagram of the packaging structure of the optical sensor provided in the embodiments of this application;

[0025] Figure 5 A schematic diagram showing the comparison simulation structure and simulation results provided for embodiments of this application;

[0026] Figure 6Simulation illustration of the packaging structure provided in the embodiments of this application Figure 1 ;

[0027] Figure 7 Simulation illustration of the packaging structure provided in the embodiments of this application Figure 2 .

[0028] The accompanying drawings have illustrated specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to specific embodiments. Detailed Implementation

[0029] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0030] First, let me explain the terms used in this application:

[0031] PCB: refers to the substrate structure that carries sensor chips and provides electrical connections;

[0032] Sensor chip: refers to the core device that converts optical signals into electrical signals;

[0033] Filter glass: refers to optical elements used to filter light of a specific wavelength;

[0034] Transparent adhesive layer: refers to the colloidal material used to bond the filter glass and the sensor chip;

[0035] Molding layer: refers to the packaging material that covers the sensor chip and its surrounding structure;

[0036] Sloping edge structure: refers to a geometric shape where the edge is sloping rather than right angle or flat.

[0037] Currently, the industry commonly uses Chip on Board (COB) packaging for optical sensors. Its core design involves directly bonding a filter glass to the surface of the sensor chip using a specialized adhesive to form a monolithic structure. This monolithic structure is then encapsulated between glass fiber (GF) material and a printed circuit board (PCB) substrate. To avoid the arcing of wire bonding lines at the edge pads of the sensor chip, a stepped glass configuration is typically designed between the monolithic structure and the GF material. This involves creating a stepped geometric structure at the edge of the monolithic structure, such as... Figure 1 As shown; or, as Figure 2 As shown, the overall structure and the GF material are designed with a flat-edge glass configuration, meaning the edge area of ​​the overall structure is machined to have a flat edge. Figure 1 and Figure 2 In the middle, the edges of the overall structure are all highly consistent with the GF material.

[0038] like Figure 1 and Figure 2 As shown, the top surface of the molding compound is flush with the surface of the filter glass. However, during actual processing, due to adhesive flow issues, the height of the filter glass can easily fall below the molding compound, creating a new stress concentration area. See [link to documentation] for details. Figure 3 New stress concentration areas can make the filter glass highly susceptible to cracking or breakage.

[0039] To address the aforementioned issues, this application provides a packaging structure for an optical sensor that uses a ramped edge structure instead of the traditional stepped or flat edge design, thereby optimizing and dispersing stress concentration at the glass edge through geometric morphology.

[0040] This application is mainly used in vehicle-mounted optical sensors (such as lidar, vision sensors, etc.) in intelligent driving systems. Its core structure includes a filter glass, a transparent adhesive layer, a sensor chip, a molding layer, and a PCB substrate.

[0041] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0042] Figure 4 This is a schematic diagram of the packaging structure of the optical sensor provided in the embodiments of this application, as shown below. Figure 4 As shown, the packaging structure includes:

[0043] The components include a PCB substrate f, a sensor chip c, a filter glass a, a transparent adhesive layer b, and a molding layer e, wherein the filter glass a has a sloping edge structure.

[0044] The first surface of the filter glass a is bonded to the upper surface of the sensor chip c through a transparent adhesive layer b, and the lower surface of the sensor chip c is fixed to the upper surface of the PCB substrate f to form an integral structure.

[0045] The molding layer e covers the edge area of ​​the overall structure, and the top surface of the molding layer e is coplanar and flush with the second surface of the filter glass a.

[0046] In this embodiment, the first surface of the filter glass is first bonded to the upper surface of the sensor chip through a transparent adhesive layer, thereby forming a channel for optical signal transmission. The optical transparency of the transparent adhesive layer can ensure lossless transmission of optical signals between the filter glass and the sensor chip.

[0047] The lower surface of the sensor chip is fixed to the upper surface of the PCB substrate, and the PCB substrate provides electrical connection and heat dissipation path to reduce deformation differences when the temperature changes.

[0048] Optionally, the lower surface of the sensor chip can be fixed to the upper surface of the PCB substrate using a die attach (DA) adhesive patch d. It should be noted that this is merely an example, and this application does not limit the specific implementation method of fixing the lower surface of the sensor chip to the upper surface of the PCB substrate.

[0049] Furthermore, the molding layer e covers the edge area of ​​the overall structure, and the top surface of the molding layer is coplanar and flush with the second surface of the filter glass, thereby ensuring the flatness of the encapsulation structure and eliminating new stress concentration areas.

[0050] Furthermore, the sloped edge structure of the aforementioned filter glass, through geometrical changes, creates a continuous curvature in the transition area between the glass edge and the molding layer, avoiding stress concentration in traditional right-angle steps or flat edge designs, thereby reducing the risk of filter glass failure such as cracking or breakage.

[0051] This application's embodiments address the cracking problem caused by stress concentration at the edge of the filter glass in existing packaging by optimizing the design of the ramp edge structure. The ramp edge structure transforms the stress concentration points in the right-angle region of the traditional stepped structure into a gradient stress distribution along the ramp angle by altering the geometry of the filter glass edge. The optimized ramp angle design creates a continuous curvature in the transition region between the filter glass edge and the molding layer, avoiding abrupt stress changes. This design significantly reduces the risk of filter glass cracking or breakage by lowering local stress peaks at the filter glass edge. Furthermore, the adaptable curvature radius design of the ramp edge structure can accommodate differences in thermal stress from different material parameters, further improving the crack resistance of the filter glass during high and low temperature cycling tests. Ultimately, the above solution directly solves the problem of cracking or breakage caused by stress concentration at the filter glass edge from a structural design perspective, thereby comprehensively ensuring the reliability of optical sensors in extreme environments.

[0052] Based on the above embodiments, in some examples, the edge angle of the slope edge structure ranges from 60° to 70°. Here, the edge angle refers to the angle between the slope edge of the filter glass and the horizontal plane; adjusting this angle can adjust and change the stress distribution.

[0053] In the example above, the edge angle of the ramp edge structure is limited to 60°-70°. Through the optimized design of this edge angle range, a continuous curvature is formed between the edge of the filter glass and the transition area of ​​the molding layer. The ramp edge structure with this edge angle range can effectively disperse the stress concentration at the glass edge and avoid the crack initiation caused by stress abrupt changes in traditional right-angle step or flat edge designs.

[0054] The above example achieves a more precise stress dispersion effect by limiting the edge angle of the sloped edge structure to 60°-70°. This angle range effectively balances stress dispersion and structural strength, avoiding insufficient edge strength caused by excessive tilting, while maximizing the contact area between the sloped area and the molding layer, further reducing the local stress peak at the edge of the filter glass.

[0055] Furthermore, in some other examples, the glass thickness of the filter glass is 0.5 mm - 0.6 mm.

[0056] Since the thickness of the filter glass directly affects its ability to resist external stress, this application embodiment limits the glass thickness to a range of 0.5 mm to 0.6 mm. This thickness range is not arbitrary but precisely designed to achieve the following interrelated technical objectives:

[0057] Ensuring robustness and reliability: The thickness of the filter glass directly affects its strength. A thickness less than 0.5 mm may cause the filter glass to deform, crack, or detach due to insufficient strength when subjected to stresses generated by environmental changes on the PCB substrate. On the other hand, excessive thickness, exceeding 0.6 mm, while enhancing the strength of the filter glass, may increase the risk of stress concentration and is not conducive to the design of a thinner and lighter packaging structure. Therefore, the 0.5 mm-0.6 mm range aims to provide a balance between strength and stress resistance that meets the reliability requirements of the sensor.

[0058] Optimizing stress transfer and mitigation: The thickness and rigidity of the filter glass are closely related, thus affecting the stress transfer mechanism between it and the PCB substrate. When the PCB substrate deforms under temperature changes, filter glass of different thicknesses will respond in different ways. By controlling the thickness within the range of 0.5mm-0.6mm, the embodiments of this application can more effectively manage and mitigate the stress transferred to the filter glass, avoid stress concentration, and thus reduce the risk of filter glass failure.

[0059] Matching Optical Performance and System Integration: The thickness of the filter glass not only affects its mechanical properties but can also influence its optical characteristics, such as light transmittance, spectral response shape, and interference effects. The 0.5mm-0.6mm range is determined based on optical design requirements to ensure that the filter glass provides the desired spectral filtering effect while achieving the aforementioned mechanical and stress control goals, thus meeting the overall performance specifications of the optical sensor. Furthermore, the thickness directly affects the overall size and height of the optical sensor; the 0.5mm-0.6mm range must also consider its integration and compatibility with the PCB substrate, other optical components, and packaging.

[0060] In summary, setting the thickness of the filter glass in the range of 0.5mm-0.6mm is a key technical choice. It works synergistically to improve the mechanical reliability of the filter glass, optimize stress transmission, ensure optical performance, and take into account the overall integration of the device, thus supporting the stable operation of the optical sensor in a high-reliability environment.

[0061] Furthermore, in order to improve the reliability of the filter glass under high stress environment, in the embodiments of this application, the filter glass used in the optical sensor is selected to have a tensile strength higher than 100MPa. Specifically, the tensile strength of the filter glass is ≥100MPa.

[0062] This measure aims to ensure that the filter glass can effectively resist tensile stress from thermal expansion and contraction of the PCB substrate, external impacts, etc., thereby significantly reducing the risk of breakage of the filter glass under high and low temperature cycling or vibration conditions, and improving the service life and stability of the entire optical sensor.

[0063] Furthermore, filter glass can have both infrared filter (IR) function and cover glass (CG) protection function; it can also have IR function; or it can have CG function.

[0064] Furthermore, in some examples, the coefficient of thermal expansion of the PCB substrate ranges from 12ppm / ℃ to 15ppm / ℃, and the elastic modulus of the PCB substrate ranges from 22000MPa to 24000MPa. Here, the coefficient of thermal expansion of the PCB substrate refers to the ratio of the deformation of the PCB substrate material to the amount of temperature change; the elastic modulus of the PCB substrate refers to the ratio of stress to strain of the PCB substrate material during the elastic deformation stage.

[0065] In the example above, the coefficient of thermal expansion of the PCB substrate is 12ppm / ℃-15ppm / ℃, and the elastic modulus is 22000MPa-24000MPa. By selecting parameters within this range, the deformation of the PCB substrate during high and low temperature cycling is kept within a reasonable range.

[0066] This reasonable range refers to the stress level transmitted to the filter glass by the PCB substrate when it deforms within the target operating temperature range, which is controlled below the allowable stress threshold of the filter glass material. This is intended to prevent the filter glass from undergoing permanent deformation, cracking, delamination, or functional failure due to excessive stress.

[0067] Furthermore, the reasonable range also refers to the fact that the deformation of the PCB substrate itself is also limited to a certain range, so as to ensure that the deformation will not cause the optical sensor integrated on it or other optical components that work together with the filter glass to deviate from their preset alignment position by a certain amount, thereby ensuring the overall accuracy and normal function of the optical system.

[0068] To verify the effectiveness of the packaging structure provided in the embodiments of this application, simulation verification was performed, and specific simulation diagrams are provided. Figure 5 This is a schematic diagram of the comparative simulation structure and simulation results provided in an embodiment of this application. The parameters used in this comparative simulation structure represent a commonly used material selection method in the industry. Figure 5 As shown, the deformation of the filter glass is larger in the control simulation structure.

[0069] Figure 6 Simulation illustration of the packaging structure provided in the embodiments of this application Figure 1In this simulation diagram, the coefficient of thermal expansion of the PCB substrate is between 12ppm / ℃ and 15ppm / ℃, and the value of the elastic modulus is between 22000MPa and 24000MPa.

[0070] By comparison Figure 5 and Figure 6 The simulation results can intuitively demonstrate the packaging structure of the embodiments of this application. Compared with the control simulation model, the deformation range of the filter glass is significantly reduced.

[0071] In summary, the embodiments of this application alleviate the thermal expansion mismatch problem between the PCB substrate and the glass adhesive layer by synergistically selecting the thermal expansion coefficient and elastic modulus of the PCB substrate. Furthermore, the selection of the range of thermal expansion coefficient and elastic modulus parameters of the PCB substrate can reduce the direct stress transmission of thermal deformation of the PCB substrate to the filter glass, thereby improving the overall reliability of the packaging structure.

[0072] Based on the above embodiments, in some possible implementations, the coefficient of thermal expansion of the transparent adhesive layer ranges from 10ppm / ℃ to 20ppm / ℃, and the elastic modulus parameter of the transparent adhesive layer ranges from 10000MPa to 13000MPa. Here, the coefficient of thermal expansion of the transparent adhesive layer refers to the ratio of the deformation of the material to the amount of temperature change; the elastic modulus of the transparent adhesive layer refers to the ratio of stress to strain of the material during the elastic deformation stage.

[0073] In these possible implementations, the coefficient of thermal expansion of the transparent adhesive layer used to fix the filter glass in the encapsulation structure is limited to the range of 10ppm / ℃-20ppm / ℃, and its elastic modulus is limited to the range of 10000MPa-13000MPa. These parameter ranges were determined through optimized selection.

[0074] The aforementioned specific range of coefficients of thermal expansion and modulus of elasticity is intended to: reduce the interfacial thermal stress generated between the PCB substrate and the filter glass when the PCB substrate deforms under high and low temperature cycling, preventing stress concentration from causing the filter glass to crack; provide appropriate adhesive rigidity to ensure that the filter glass can be firmly fixed when subjected to external stress, while avoiding the transparent adhesive layer itself becoming a bottleneck for stress transmission; and ensure that the transparent adhesive layer has good dimensional stability and optical transmittance throughout the entire operating temperature range, meeting the accuracy and performance requirements of optical sensors.

[0075] To verify the effectiveness of the packaging structure provided in the embodiments of this application, simulation verification was performed, and specific simulation diagrams are provided. Figure 7 Simulation illustration of the packaging structure provided in the embodiments of this application Figure 2 .

[0076] exist Figure 7 In this simulation diagram, the coefficient of thermal expansion of the transparent adhesive layer ranges from 10ppm / ℃ to 20ppm / ℃, and the elastic modulus of the transparent adhesive layer ranges from 10000MPa to 13000Mpa.

[0077] By comparison Figure 5 and Figure 7 The simulation results can intuitively demonstrate the packaging structure of the embodiments of this application. Compared with the control simulation model, the deformation range of the filter glass is significantly reduced.

[0078] In summary, the above implementation significantly improves the reliability, durability, and service life of optical sensors under harsh environments such as high and low temperature cycling by setting the coefficient of thermal expansion and elastic modulus of the transparent adhesive layer within a specific range of 10ppm / ℃-20ppm / ℃ and 10000MPa-13000Mpa.

[0079] Furthermore, in some examples, the molding compound is made of a molding compound containing glass fiber or an epoxy molding compound; and / or, the molding compound extends upward from the upper surface of the PCB substrate, and the outer sidewall of the molding compound has a smoothly transitioning slope or arc structure.

[0080] In this example, it can be seen that the molding compound of the encapsulation structure uses a molding compound containing glass fiber or an epoxy molding compound, and the choice of this material is based on the following considerations:

[0081] First, the glass fiber-infused molding compound is designed to provide high-performance physical support. This molding compound utilizes a uniformly distributed proportion of glass fibers within a polymer matrix, leveraging the fibers' high tensile strength and high elastic modulus to bear the primary load, thereby significantly enhancing the overall mechanical strength and stiffness of the encapsulation structure. Simultaneously, the low thermal expansion of glass fibers effectively offsets thermal deformation of the matrix material, improving dimensional stability and heat resistance. This makes this composite material an ideal encapsulation choice for high-stress, high-precision, and harsh environmental requirements.

[0082] Secondly, epoxy resin molding compounds emphasize the maturity and standardization of the process. As a mainstream material in the field of electronic packaging, its core advantages lie in the premixing optimization of its components and its high degree of processing convenience. By adapting to mature molding processes, epoxy resin molding compounds can ensure the consistency and reliability of packaging in large-scale production, meeting the dual requirements of basic protection and efficient manufacturing of electronic components.

[0083] Furthermore, in these examples, the outer wall of the molding compound is designed as a smoothly transitioning bevel or arc structure. This ensures good adhesive flow and prevents the glass height from falling below the molding compound due to processing errors, thereby eliminating new stress concentration areas and ensuring the reliability of the optical sensor.

[0084] It should be understood that the designations of the transparent adhesive layers in the above examples are illustrative based on their functional positions within the device. Specifically, IR adhesive refers to the adhesive layer used to bond filters, Glass on Sensor (GOS) adhesive refers to the adhesive layer used to bond glass, and CG adhesive refers to the adhesive layer used to bond sensors.

[0085] The aforementioned functional naming does not constitute an exclusive limitation on the composition of the adhesive layer material. Regarding the specific definition of the adhesive layer material properties, in the technical solution of this embodiment, the material type of the associated encapsulation layer is used as the distinguishing basis. Adhesive layers that can achieve the same bonding function and whose material properties meet the encapsulation layer definition criteria should all fall within the protection scope of this application embodiment.

[0086] This application embodiment also provides an optical sensor packaging structure, including a PCB substrate, a sensor chip, a filter glass, a transparent adhesive layer, and a molding compound layer. The first surface of the filter glass is bonded to the upper surface of the sensor chip through the transparent adhesive layer, and the lower surface of the sensor chip is fixed to the upper surface of the PCB substrate to form an integral structure. The molding compound layer covers the edge area of ​​the integral structure, and the top surface of the molding compound layer is coplanar and flush with the second surface of the filter glass. The coefficient of thermal expansion of the PCB substrate is in the range of 12ppm / ℃-15ppm / ℃, and the elastic modulus parameter of the PCB substrate is in the range of 22000MPa-24000MPa; and / or, the coefficient of thermal expansion of the transparent adhesive layer is in the range of 10ppm / ℃-20ppm / ℃, and the elastic modulus parameter of the transparent adhesive layer is in the range of 10000MPa-13000MPa.

[0087] In this embodiment, the first surface of the filter glass is first bonded to the upper surface of the sensor chip via a transparent adhesive layer, thereby forming a channel for optical signal transmission. The lower surface of the sensor chip is fixed to the upper surface of the PCB substrate, which provides electrical connections and heat dissipation paths to reduce deformation differences due to temperature changes.

[0088] Optionally, the lower surface of the sensor chip can be fixed to the upper surface of the PCB substrate using DA adhesive. It should be noted that this is merely an example, and the specific implementation method for fixing the lower surface of the sensor chip to the upper surface of the PCB substrate is not limited in this application.

[0089] Furthermore, the molding compound covers the edge area of ​​the overall structure, and the top surface of the molding compound is coplanar and flush with the second surface of the filter glass, thereby ensuring the flatness of the encapsulation structure and eliminating new stress concentration areas.

[0090] Furthermore, in this embodiment, parameters such as the coefficient of thermal expansion of the PCB substrate, the elastic modulus of the PCB substrate, the coefficient of thermal expansion of the transparent adhesive layer, and the elastic modulus of the transparent adhesive layer are defined. The specific principle of parameter definition has been explained in detail in the previous embodiments, therefore, it will not be repeated here.

[0091] Based on the above embodiments, this application provides an optical sensor, including the packaging structure described in the above embodiments.

[0092] Furthermore, embodiments of this application also provide a mobile platform, including an optical sensor as described in the above embodiments.

[0093] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., 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 this disclosure. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0094] In the description of the embodiments of this application, it should be understood that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection or an indirect connection through an intermediate medium, or the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances. The terms "upper," "lower," "front," "rear," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this application. In the description of this application, "multiple" means two or more, unless otherwise precisely specified.

[0095] The terms "first," "second," "third," "fourth," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the application described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0096] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A packaging structure for an optical sensor, characterized in that, include: The components include a printed circuit board (PCB) substrate, a sensor chip, a filter glass, a transparent adhesive layer, and a molding compound, wherein the filter glass has a sloping edge structure. The first surface of the filter glass is bonded to the upper surface of the sensor chip through the transparent adhesive layer, and the lower surface of the sensor chip is fixed to the upper surface of the PCB substrate to form an integral structure. The molding layer covers the edge region of the overall structure, and the top surface of the molding layer is coplanar and flush with the second surface of the filter glass.

2. The packaging structure according to claim 1, characterized in that, The edge angle of the slope edge structure ranges from 60° to 70°.

3. The packaging structure according to claim 1 or 2, characterized in that, The thickness of the filter glass is 0.5mm-0.6mm.

4. The packaging structure according to claim 1 or 2, characterized in that, The tensile strength of the filter glass is ≥100MPa.

5. The packaging structure according to claim 1 or 2, characterized in that, The coefficient of thermal expansion of the PCB substrate ranges from 12ppm / ℃ to 15ppm / ℃, and the elastic modulus of the PCB substrate ranges from 22000MPa to 24000MPa.

6. The packaging structure according to claim 1 or 2, characterized in that, The coefficient of thermal expansion of the transparent adhesive layer ranges from 10ppm / ℃ to 20ppm / ℃, and the elastic modulus of the transparent adhesive layer ranges from 10000MPa to 13000Mpa.

7. The packaging structure according to claim 1 or 2, characterized in that, The molding compound is made of a molding compound containing glass fiber or an epoxy resin molding compound. And / or, the molding layer extends upward from the upper surface of the PCB substrate, and the outer sidewall of the molding layer has a smoothly transitioned slope or arc structure.

8. A packaging structure for an optical sensor, characterized in that, This includes printed circuit board (PCB) substrate, sensor chip, filter glass, transparent adhesive layer, and molding compound. The first surface of the filter glass is bonded to the upper surface of the sensor chip through the transparent adhesive layer, and the lower surface of the sensor chip is fixed to the upper surface of the PCB substrate to form an integral structure. The molding layer covers the edge area of ​​the integral structure, and the top surface of the molding layer is coplanar and flush with the second surface of the filter glass. The coefficient of thermal expansion of the PCB substrate ranges from 12ppm / ℃ to 15ppm / ℃, and the elastic modulus of the PCB substrate ranges from 22000MPa to 24000MPa; and / or, the coefficient of thermal expansion of the transparent adhesive layer ranges from 10ppm / ℃ to 20ppm / ℃, and the elastic modulus of the transparent adhesive layer ranges from 10000MPa to 13000MPa.

9. An optical sensor, characterized in that, Includes the packaging structure as described in any one of claims 1 to 8.

10. A portable platform comprising the optical sensor as claimed in claim 9.

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