Packaging structure and sensor

Abstract

The utility model provides a packaging structure and a sensor, relates to the field of microelectronic device packaging, and aims to reduce damage to functional devices in an integrated circuit substrate caused by solder sputtering in the packaging process of the integrated circuit substrate. The packaging structure comprises an integrated circuit substrate, an opposite substrate, a blocking structure and a connecting structure. The integrated circuit substrate and the opposite substrate are oppositely arranged in the first direction, the connecting structure is connected between the opposite substrate and the integrated circuit substrate, and a containing cavity is defined by the connecting structure, the opposite substrate and the integrated circuit substrate. The integrated circuit substrate comprises a functional device arranged in the accommodating cavity. The blocking structure is arranged in the accommodating cavity and is arranged between the functional device and the connecting structure. As the blocking structure is located between the integrated circuit substrate and the connecting structure, the sputtered solder particles hit the surface of the side, close to the connecting structure, of the blocking structure, the solder particles are prevented from being sputtered to the functional device, the microstructure of the functional device is prevented from being scratched, the functional device is protected, and the product yield is improved.

Description

Technical Field

[0001] This utility model relates to the field of microelectronic device packaging, specifically to a packaging structure and a sensor. Background Technology

[0002] In the process of manufacturing highly integrated micro-mechanical and electronic systems using microfabrication technology, the integrated circuit substrate is packaged to prevent damage to the integrated circuit substrate from the external environment (such as dust, moisture, and chemicals) and to ensure the long-term stable operation of the integrated circuit substrate.

[0003] However, in the process of encapsulating integrated circuit substrates with solder, methods such as electroplating and evaporation are usually used to process the solder. These conventional methods inevitably introduce impurities or create voids within the solder. When the solder melts and is used for eutectic bonding, the impurities and voids within the solder can rapidly explode at high temperatures. This explosion causes some tiny particles from the solder to sputter onto the integrated circuit substrate, thereby damaging the microstructure of the integrated circuit substrate. Utility Model Content

[0004] This utility model provides a packaging structure and sensor, which aims to reduce the damage to functional devices in the integrated circuit substrate caused by solder sputtering during the packaging process.

[0005] To achieve the above objectives, the embodiments of this utility model adopt the following technical solutions:

[0006] In a first aspect, this application provides a packaging structure including an integrated circuit substrate, a counter substrate, a barrier structure, and a connection structure. The integrated circuit substrate and the counter substrate are disposed opposite each other along a first direction, which is the thickness direction of the integrated circuit substrate. The connection structure connects the counter substrate and the integrated circuit substrate to form a receiving cavity with the counter substrate and the integrated circuit substrate. The integrated circuit substrate includes functional devices disposed within the receiving cavity. The barrier structure is disposed within the receiving cavity and between the functional devices and the connection structure.

[0007] The functional devices of the packaging structure provided in this application are located in a cavity composed of an integrated circuit substrate, a connection structure, and a counter substrate. A barrier structure is also located in the cavity composed of the connection structure and the counter substrate, between the connection structure and the functional devices on the integrated circuit substrate. When the solder in the connection structure melts for eutectic bonding, impurities and voids in the solder will rapidly explode at high temperatures. This explosion causes some solder particles to sputter outwards. Because the barrier structure is located between the integrated circuit substrate and the connection structure, the sputtered solder particles will hit the surface of the barrier structure closest to the connection structure, thereby preventing solder particles from sputtering onto the functional devices. This prevents scratches on the microstructure of the functional devices during the packaging process, protects the functional devices, and improves product yield.

[0008] As one possible implementation, a barrier structure is set around the functional device.

[0009] As one possible implementation, the packaging structure also includes a limiting element connected between the blocking structure and the connecting structure.

[0010] As one possible implementation, there are multiple limiting elements, which are arranged at circumferential intervals along the functional device.

[0011] As one possible implementation, the limiting members arranged circumferentially along the functional device are configured to limit the movement of the blocking structure in a first direction and to limit the movement of the blocking structure in a second direction; the second direction is perpendicular to the first direction.

[0012] As one possible implementation, multiple limiting members are respectively connected to the midpoints of multiple sides of the blocking structure. Alternatively, multiple limiting members are respectively connected to multiple corner positions of the blocking structure.

[0013] As one possible implementation, the limiting member and the blocking structure are integrated, with the end of the limiting member away from the blocking structure abutting against the connecting structure. Alternatively, the limiting member and the connecting structure are integrated, with the end of the limiting member away from the connecting structure abutting against the blocking structure.

[0014] As one possible implementation, the connection structure includes a riser ring and two solder layers. The riser ring surrounds the functional device, and the two solder layers are located on opposite sides of the riser ring in a first direction, facing the substrate. The blocking structure and the riser ring are connected by a limiting member.

[0015] As one possible implementation, the blocking structure includes a first end and a second end opposite to each other in a first direction, the first end of the blocking structure being connected to the integrated circuit substrate, and the second end of the blocking structure being connected to the opposing substrate.

[0016] In one possible implementation, a first groove is formed on the surface of the integrated circuit substrate near the opposing substrate, and a first end of the blocking structure is embedded in the first groove. And / or, a second groove is formed on the surface of the opposing substrate near the integrated circuit substrate, and a second end of the blocking structure is embedded in the second groove.

[0017] Secondly, this application also provides a sensor, which includes a lens assembly and a packaging structure as mentioned in the first aspect and its possible implementations, wherein the lens assembly and the packaging structure are connected.

[0018] The beneficial effects of the second aspect can be referred to the beneficial effects of the first aspect, and will not be elaborated here. Attached Figure Description

[0019] Figure 1 This is a cross-sectional schematic diagram of an encapsulation structure provided in an embodiment of this application;

[0020] Figure 2 A top view of an encapsulation structure provided in an embodiment of this application;

[0021] Figure 3 A top view of another packaging structure provided in an embodiment of this application;

[0022] Figure 4 A top view of another packaging structure provided in an embodiment of this application;

[0023] Figure 5 A cross-sectional schematic diagram of another packaging structure provided in an embodiment of this application;

[0024] Figure 6 A cross-sectional schematic diagram of another packaging structure provided in an embodiment of this application;

[0025] Figure 7 This is a schematic diagram of a sensor provided in an embodiment of this application. Detailed Implementation

[0026] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0027] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0028] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances. Furthermore, when describing pipelines, the terms "connected" and "linked" in this utility model have the meaning of establishing conductivity. The specific meaning needs to be understood in conjunction with the context.

[0029] In this embodiment of the invention, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design described as "exemplary" or "for example" in this embodiment of the invention should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of the terms "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0030] Micro-Electro-Mechanical Systems (MEMS) are an integrated technology that combines microelectronics and mechanical technology, and are widely used in various fields. One of the core components of MEMS is the functional devices on the integrated circuit substrate. For example, the combination of different types of functional devices can create the diversity of functions of the integrated circuit substrate. Therefore, ensuring the stability and reliability of the functional devices is of paramount importance.

[0031] In the process of manufacturing highly integrated micro-mechanical and electronic systems using microfabrication technology, the integrated circuit substrate is packaged to prevent damage from the external environment (such as dust, moisture, and chemicals) and to ensure its long-term stable operation. As mentioned in the background section, during the packaging of the integrated circuit substrate using solder, tiny particles spattered during solder processing or soldering can damage the microstructure of functional devices, thereby affecting their stability and reliability.

[0032] In view of this, this application provides an encapsulation structure, exemplarily, such as... Figure 1 As shown. Figure 1 This is a cross-sectional view of the packaging structure, based on Figure 1It can be seen that the packaging structure 100 provided in this application includes an integrated circuit substrate 1, a counter substrate 2, a blocking structure 3, and a connection structure 4. The integrated circuit substrate 1 and the counter substrate 2 are along a first direction ( Figure 1 The components (indicated by the double arrows) are arranged opposite each other, with the first direction being the thickness direction of the integrated circuit substrate. The connecting structure 4 connects the opposing substrate 2 and the integrated circuit substrate 1 to form a receiving cavity with the opposing substrate 2 and the integrated circuit substrate 1. The integrated circuit substrate 1 includes a functional device 11 disposed within the receiving cavity. The blocking structure 3 is disposed within the receiving cavity and between the functional device 11 and the connecting structure 4.

[0033] The functional device 11 of the packaging structure 100 provided in this application is located in a cavity composed of an integrated circuit substrate 1, a connection structure 4, and a counter substrate 2. The barrier structure 3 is also located in the cavity composed of the connection structure 4 and the counter substrate 2, and is positioned between the connection structure 4 and the functional device 11 of the integrated circuit substrate 1. When the solder in the connection structure 4 melts and performs eutectic bonding, impurities and voids in the solder will rapidly explode at high temperatures. The explosion causes some of the solder particles to sputter outward. Since the barrier structure 3 is located between the integrated circuit substrate 1 and the connection structure 4, the sputtered solder particles will hit the surface of the barrier structure 3 near the connection structure 4, thereby preventing solder particles from sputtering onto the functional device 11, preventing scratches on the microstructure of the functional device 11 of the integrated circuit substrate 1 during the packaging process, protecting the functional device 11, and improving product yield.

[0034] In some embodiments, the opposing substrate 2 is a light window; in other embodiments, the opposing substrate is a conventional housing structure without a light window.

[0035] In some embodiments, the integrated circuit substrate 1 includes at least one of an infrared focal plane array, a gyroscope, an accelerometer, and a pressure gauge, and the functional device 11 is a silicon-based readout circuit adapted to the integrated circuit substrate.

[0036] It should be noted that the embodiments of this application do not limit the specific location or size of the blocking structure. For example, Figure 2 As shown, Figure 2 Three possible top views of the functional device 11 and the blocking structure 3 are shown. As one possible implementation, such as... Figure 2 As shown in (a), the blocking structure 3 is arranged around the functional device 11, as one possible implementation, such as Figure 2 As shown in (b), the blocking structure 3 is arranged in two C-shapes opposite each other on both sides of the functional device 11. As one possible implementation, such as... Figure 2 As shown in (c), the blocking structure 3 is C-shaped and disposed on one side of the functional device 11.

[0037] This application does not limit the distance between the blocking structure 3 and the functional device 11, nor does it limit the size of the blocking structure along the first direction. As long as it is within the receiving cavity and located between the functional device 11 and the connecting structure 4, it can achieve the function of blocking the sputtering of small solder particles. It should also be understood that when the blocking structure 3 is arranged around the functional device 11 and the size of the blocking structure 3 in the first direction is as large as possible, it can block the sputtering of small particles from all directions as much as possible, thus providing a higher level of protection. However, it is still necessary to select the appropriate method based on the actual situation.

[0038] As one possible implementation, for example, such as Figure 3 As shown, the packaging structure 100 also includes a limiting member 5, which is connected between the blocking structure 3 and the connecting structure 4. The limiting member 5 can stably fix the blocking structure 3 between the functional device 11 and the connecting structure, preventing the blocking structure 3 from shifting or even tipping over due to interference or collision from the external environment, thereby further improving the overall stability of the packaging structure.

[0039] In some embodiments, exemplarily, such as Figure 3 and Figure 4 As shown, there are multiple limiting members 5, which are arranged at intervals along the circumference of the functional device 11. Circumferential direction refers to the direction of rotation around the center point, that is, around the functional device 11 in a clockwise or counterclockwise direction. Figure 3 and Figure 4 The example shown is based on the fact that four limiting components have been set in each part.

[0040] For example, refer to Figure 3 and Figure 5 The limiting members 5, arranged circumferentially along the functional device 11, are configured to: restrict the blocking structure 3 in the first direction (i.e., Figure 5 The movement of the blocking structure 3 in the Y direction is limited, and the movement of the blocking structure 3 in the second direction (i.e., Figure 5 The movement in the X direction is limited. The second direction is perpendicular to the first direction.

[0041] As one possible implementation, the connecting structure 4 is welded between the integrated circuit substrate 1 and the opposing substrate 2, resulting in a stable structure that is difficult to displace due to interference or collision from the external environment. Since the limiting member 5 is connected between the blocking structure 3 and the connecting structure 4, and limits the movement of the blocking structure 3 in both the first and second directions, the blocking structure 3 cannot undergo significant displacement in the first direction or in the second direction within the cavity formed by the connecting structure 4, the integrated circuit substrate 1, and the opposing substrate 2. This makes the fixing of the blocking structure 3 between the integrated circuit substrate 1 and the opposing substrate 2 more stable, preventing the blocking structure 3 from shifting or even tipping over due to interference or collision from the external environment, further improving the overall stability of the packaging structure.

[0042] As one possible implementation, such as Figure 3 and Figure 4 As shown, multiple limiting members 5 are respectively connected to the midpoints of multiple sides of the blocking structure 3. Alternatively, multiple limiting members 5 are respectively connected to multiple corner positions of the blocking structure 3.

[0043] The limiting member 5 is located at the midpoint of multiple sides of the blocking structure 3, which makes the force more uniform, reduces stress concentration in the structure, and improves the overall stability of the structure. In addition, since multiple limiting members 5 are located at the midpoint, the force on both sides of the blocking structure 3 is relatively symmetrical when subjected to external forces, which helps to maintain the balance of the blocking structure 3.

[0044] The limiting members 5 are connected to multiple corner positions of the blocking structure 3. The limiting members 5 at the corners can directly participate in the stress transfer at the corners, which helps to improve the deformation resistance of the blocking structure 3 and also makes the blocking structure 3 and the connecting structure more compact, saving space. In addition, corners are usually the more stable parts of the structure, and the limiting members 5 connecting the blocking structure 3 and the connecting structure at the corners can provide stronger support.

[0045] In some embodiments, such as Figure 3 As shown, the blocking structure 3 and the limiting member 5 are integrally formed, and the end of the limiting member 5 away from the blocking structure 3 abuts against the connecting structure 4. Figure 3 (a) illustrates the case where the blocking structure 3 and the limiting member 5 are integrated, and multiple limiting members 5 are located at the midpoint. Figure 3 (b) illustrates a case where the blocking structure 3 and the limiting member 5 are integrated, and multiple limiting members 5 are located at a corner.

[0046] In other embodiments, such as Figure 4 As shown, the limiting member 5 is integrally set with the connecting structure 4, and the end of the limiting member 5 away from the connecting structure 4 abuts against the blocking structure 3. Figure 4(a) illustrates the case where the limiting member 5 is integrated with the connecting structure 4, and multiple limiting members 5 are located at the midpoint. Figure 4 (b) illustrates the case where the limiting member 5 is integrated with the connecting structure 4, and multiple limiting members 5 are located at the corner.

[0047] It should be noted that this application does not limit the shape of the limiting member 5. The shape of multiple limiting members 5 can be one or more of the following: rectangle, semicircle or other shapes. The shapes of multiple limiting members 5 can be the same or different.

[0048] As one possible implementation, such as Figure 5 As shown. The connecting structure 4 includes a riser ring 41 and two welded layers 42. The riser ring 41 surrounds the functional device 11, and the two welded layers 42 are located on both sides of the riser ring 41 in the first direction. The blocking structure 3 and the riser ring 41 are connected by a limiting member 5.

[0049] The shim ring 41 is used to increase the distance between the opposing substrate 2 and the integrated circuit substrate 1, thereby improving the imaging defects caused by the deposition of fine particles from the external environment on the opposing substrate 2. As one possible implementation, the shim ring 41 may be made of at least one of the following materials: silicon, a metallic material such as Kovar alloy, or a ceramic material.

[0050] The solder layer 42 is provided to better connect the shim ring 41 to the opposing substrate 2 and the integrated circuit substrate 1. As one possible implementation, the solder layer 42 includes solder and a composite metal. The composite metal includes at least one of Cr / Au, Cr / Ni / Au, and Ti / Pt / Au. The solder layer 42 closest to the integrated circuit substrate 1 is primarily composed of Cr and Ti, serving as an adhesion layer and designed to connect the bottom of the shim ring 41 to the integrated circuit substrate 1. The solder layer 42 closest to the opposing substrate 2 is primarily composed of Ni and Pt, serving as a wetting layer and designed to achieve eutectic brazing with the solder. The solder can be a single metal or a combination of alloys, such as Sn-based solder, Sn-In, Sn-Ag, Sn-Au, Sn-Ag-Cu solders, In-based solder, and at least one of In and InAg.

[0051] In some embodiments, exemplarily, such as Figure 6 As shown. The blocking structure 3 includes a first end 31 and a second end 32 opposite to each other in a first direction. The first end 31 of the blocking structure 3 is connected to the integrated circuit substrate 1, and the second end 32 of the blocking structure 3 is connected to the opposing substrate 2.

[0052] Specifically, in some embodiments, the surface of the integrated circuit substrate 1 near the opposing substrate 2 is provided with a first slot 12, and the first end 31 of the blocking structure 3 is embedded in the first slot 12.

[0053] In other embodiments, a second slot 21 is provided on the surface of the opposing substrate 2 near the integrated circuit substrate 1, and the second end 42 of the blocking structure 3 is embedded in the second slot 21.

[0054] In some other embodiments, the surface of the integrated circuit substrate 1 near the opposing substrate 2 is provided with a first slot 12, and the first end 31 of the blocking structure 3 is embedded in the first slot 12. Furthermore, the surface of the opposing substrate 2 near the integrated circuit substrate 1 is provided with a second slot 21, and the second end 42 of the blocking structure 3 is embedded in the second slot 21.

[0055] By providing a first slot 12 on the surface of the integrated circuit substrate 1 near the opposing substrate 2 and a second slot 21 on the surface of the opposing substrate 2 near the integrated circuit substrate 1, the two ends of the blocking structure 3 are respectively embedded into the slots, thereby fixing the blocking structure 3. The two ends of the blocking structure 3 are confined in the slots, ensuring that the blocking structure 3 will not shake or tilt significantly due to collisions or interference from the external environment, thus improving the reliability of the blocking structure 3 in preventing solder particle splashing.

[0056] As one possible implementation, the material of the barrier structure includes at least one of inorganic ceramic materials or metallic materials.

[0057] This application also provides a sensor, exemplarily, such as... Figure 7 As shown, sensor 200 includes lens assembly 50 and encapsulation structure 100 as described above, with encapsulation structure 100 connected to lens assembly 50. Because the encapsulation structure 100 in sensor 200 has a blocking structure, during eutectic bonding of molten solder, splattered solder particles are blocked by the blocking structure, thus better protecting functional devices from damage, making the integrated circuit substrate more stable and reliable, and increasing the accuracy of measurements taken by sensor 200.

[0058] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the utility model disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein.

[0059] Finally, it should be noted that the above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A packaging structure, characterized in that, include: Integrated circuit substrate, opposing substrate, barrier structure, and connection structure; The integrated circuit substrate and the opposing substrate are disposed opposite each other along a first direction, the first direction being the thickness direction of the integrated circuit substrate; The connection structure is connected between the opposing substrate and the integrated circuit substrate to form a receiving cavity with the opposing substrate and the integrated circuit substrate; The integrated circuit substrate includes a functional device disposed in the receiving cavity; the blocking structure is disposed in the receiving cavity and between the functional device and the connecting structure.

2. The packaging structure according to claim 1, characterized in that, The blocking structure is arranged around the functional device.

3. The packaging structure according to claim 1, characterized in that, The encapsulation structure further includes a limiting member, which is connected between the blocking structure and the connecting structure.

4. The packaging structure according to claim 3, characterized in that, The number of limiting members is multiple, and the multiple limiting members are arranged at intervals along the circumference of the functional device.

5. The packaging structure according to claim 4, characterized in that, The limiting members arranged circumferentially along the functional device are configured to limit the movement of the blocking structure in the first direction and to limit the movement of the blocking structure in a second direction; the second direction is perpendicular to the first direction.

6. The packaging structure according to claim 3, characterized in that, The plurality of limiting members are respectively connected to the midpoints of the plurality of sides of the blocking structure; or, The plurality of limiting members are respectively connected to the plurality of corner positions of the blocking structure.

7. The packaging structure according to claim 3, characterized in that, The limiting member is integrally formed with the blocking structure, and the end of the limiting member away from the blocking structure abuts against the connecting structure; or... The limiting member is integrally formed with the connecting structure, and the end of the limiting member away from the connecting structure abuts against the blocking structure.

8. The packaging structure according to claim 3, characterized in that, The connection structure includes a shim ring and two welding layers; the shim ring surrounds the functional device, and the two welding layers are respectively located on opposite substrates on both sides of the shim ring in the first direction; The blocking structure and the shim ring are connected by the limiting member.

9. The packaging structure according to any one of claims 1 to 8, characterized in that, The blocking structure includes a first end and a second end opposite to each other in the first direction. The first end of the blocking structure is connected to the integrated circuit substrate, and the second end of the blocking structure is connected to the opposing substrate.

10. The packaging structure according to claim 9, characterized in that, The integrated circuit substrate has a first slot on its surface near the opposing substrate, and the first end of the blocking structure is embedded in the first slot. And / or, The opposing substrate has a second slot on its surface near the integrated circuit substrate, and the second end of the blocking structure is embedded in the second slot.

11. A sensor, characterized in that, The sensor includes a lens assembly and a packaging structure as described in any one of claims 1 to 10, wherein the lens assembly and the packaging structure are connected.

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