MEMS sensor sealing structure

Abstract

The utility model relates to the technical field of microelectronic packaging, in particular to an MEMS sensor sealing structure which comprises a ceramic substrate, one side of the top of the ceramic substrate is connected with an MEMS chip, the other side of the ceramic substrate is provided with an electric signal chip, and the ceramic substrate is provided with a sealing structure for sealing the chip. The sealing structure comprises a packaging shell, a first sealing assembly located in the packaging shell and a second sealing assembly located outside the packaging shell, the first sealing assembly comprises first sealing rubber and second sealing rubber, and the second sealing assembly comprises an elastic thermal shrinkage rubber sleeve. The elastic thermal shrinkage rubber sleeve is sleeved at a connecting gap between the packaging shell and the ceramic substrate; the stability and reliability of the MEMS sensor are improved, the sealing structure protects the MEMS sensor from being influenced by the external environment through multi-layer protection and precise design, and the accuracy and long-term reliability of the MEMS sensor in various applications are ensured.

Description

Technical Field

[0001] The utility model relates to the technical field of microelectronic packaging, and particularly relates to a sealing structure of a MEMS sensor. Background Technique

[0002] A MEMS sensor, namely a micro-electromechanical system, is a multi-disciplinary and cross-cutting frontier research field developed on the basis of microelectronic technology, and is an integrated circuit fabricated using a silicon wafer; its feature is that it can measure various variables in the physical world, convert the obtained information into electrical signals that are easy to process and display. Therefore, a MEMS sensor is an interface between the physical world and the digital world. Compared with traditional sensors, it has a very wide measurement range, far higher sensitivity than traditional sensors, and also has the advantages of small size, low power consumption, good performance, and mass production.

[0003] The manufacturing process of a MEMS sensor mainly includes the following steps: 1. Wafer manufacturing, which is the basis of the MEMS manufacturing process, and the wafer is used to draw the structure of the sensor; 2. Thin film deposition, which is the sensitive part of the sensor and forms the required thin film layer on the wafer; 3. Surface micromachining technology, including operations such as reaming and surface reaction. By using micromachining technology, the sensitive elements of the sensor can be made as close as possible to the working environment, so as to accurately measure physical quantities; 4. Packaging and testing, packaging the fabricated sensor into a whole and conducting tests.

[0004] In order to ensure the stability and reliability of a MEMS sensor, a sealing structure is usually provided outside the MEMS sensor. The main function of the sealing structure is to prevent the MEMS sensor from coming into contact with the external environment in an environment of air flow, liquid or other substances, thereby ensuring the stability and reliability of the sensor. Content of the Utility Model

[0005] The purpose of the utility model is to provide a sealing structure of a MEMS sensor to solve the problems raised in the above background technique.

[0006] To achieve the above purpose, the utility model provides the following technical solution:

[0007] A sealing structure of a MEMS sensor, including a ceramic substrate, a MEMS chip is connected and arranged on one side of the top of the ceramic substrate, an electrical signal chip is arranged on the other side of the ceramic substrate on the ceramic substrate, and a sealing structure for sealing the chip is arranged on the ceramic substrate. The sealing structure includes a packaging shell, a first sealing component inside the packaging shell, and a second sealing component outside the packaging shell.

[0008] As a preferred solution of the present utility model, the encapsulation housing is arranged in a hollow structure with an open bottom to form a receiving cavity for accommodating the chip. The encapsulation housing is buckled on the ceramic substrate. An encapsulation limiting ring is provided on the circumferential wall at the bottom of the encapsulation housing, and a connection slot is provided on the inner wall of one side of the encapsulation limiting ring.

[0009] As a preferred solution of the present utility model, a ceramic ring integrally connected to the ceramic substrate is provided on the outer circumferential wall above the ceramic substrate. A plug rod matching and connected to the connection slot is provided at the bottom of one side of the ceramic ring, and a landslide structure is provided at the top of the side of the ceramic ring away from the plug rod.

[0010] As a preferred solution of the present utility model, the first sealing assembly includes a first sealing rubber and a second sealing rubber. The first sealing rubber is distributed on the inner circumferential wall inside the encapsulation housing. A sealing plug-in structure is provided at the bottom of the first sealing rubber. The second sealing rubber is located on the ceramic substrate near the outer circumferential wall, and a sealing slot matching the sealing plug-in structure is provided on the second sealing rubber. The first sealing rubber and the second sealing rubber form an encapsulation cavity for encapsulating and wrapping the chip.

[0011] As a preferred solution of the present utility model, the second sealing assembly includes an elastic heat-shrinkable rubber sleeve, and the elastic heat-shrinkable rubber sleeve is sleeved at the connection gap between the encapsulation housing and the ceramic substrate.

[0012] As a preferred solution of the present utility model, the top of the ceramic substrate abuts against the inner wall of the top of the encapsulation housing through a heat-conducting copper tube.

[0013] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0014] 1. Aiming at the problems raised in the background art, the present application improves the stability and reliability of the MEMS sensor. The sealing structure protects the MEMS sensor from the external environment through multi-layer protection and precise design, ensuring its accuracy and long-term reliability in various applications.

[0015] 2. The encapsulation housing is in a hollow structure with an open bottom for accommodating the chip. It is buckled on the ceramic substrate, and an encapsulation limiting ring is provided on the circumferential wall at the bottom for fixing and positioning.

[0016] 3. A ceramic ring integrally connected to it is provided on the outer circumferential wall above the ceramic substrate, and a plug rod at the bottom of one side is matched with the connection slot of the encapsulation housing to enhance the stability of the connection.

[0017] 4. The first sealing rubber located inside the encapsulation housing and the second sealing rubber located on the ceramic substrate form an encapsulation cavity through the cooperation of the sealing insertion structure and the sealing slot, providing a hermetic encapsulation for the chip to prevent external gases or liquids from entering the interior and ensuring the stability and reliability of the sensor.

[0018] 5. The elastic heat-shrinkable rubber sleeve is sleeved at the connection gap between the encapsulation housing and the ceramic substrate, and the elastic heat-shrinkable rubber sleeve is heat-shrunk and sealed at the connection gap between the encapsulation housing and the ceramic substrate for secondary sealing.

[0019] 6. The top of the ceramic substrate contacts the inner wall of the bottom of the encapsulation housing through a heat-conducting copper tube, which is beneficial for heat management and ensures the performance stability of the sensor when the temperature changes. Description of the Drawings

[0020] Figure 1 is a three-dimensional view of the overall structure of the present utility model;

[0021] Figure 2 is a side view of the overall encapsulation housing and the first sealing rubber of the present utility model;

[0022] Figure 3 is a side view of the ceramic substrate and the second sealing rubber of the present utility model;

[0023] Figure 4 is a side view of the elastic heat-shrinkable rubber sleeve, the encapsulation housing and the ceramic substrate of the present utility model.

[0024] In the figure: 1. Ceramic substrate; 11. MEMS chip; 12. Electrical signal chip; 2. Encapsulation housing; 21. Encapsulation limit ring; 211. Connection slot; 13. Ceramic ring; 131. Insertion rod; 132. Landslide structure; 3. First sealing rubber; 31. Sealing insertion structure; 4. Second sealing rubber; 41. Sealing slot; 5. Elastic heat-shrinkable rubber sleeve. Detailed Embodiment

[0025] Next, the technical solutions in the embodiments of the present utility model will be clearly and completely described in conjunction with the embodiments of the present utility model.

[0026] Embodiment

[0027] Please refer to Figures 1-4, the present utility model provides a technical solution: a sealing structure for a MEMS sensor, including a ceramic substrate 1. On one side of the top of the ceramic substrate 1, a MEMS chip 11 is connected and arranged. On the other side of the ceramic substrate 1 on the ceramic substrate 1, an electrical signal chip 12 is arranged. A sealing structure for sealing the chips is arranged on the ceramic substrate 1. The sealing structure includes a packaging shell 2, a first sealing component inside the packaging shell 2, and a second sealing component outside the packaging shell 2. The packaging shell 2 is arranged in a hollow structure with an open bottom to form a receiving cavity for accommodating the chips. The packaging shell 2 is buckled on the ceramic substrate 1. A packaging limiting ring 21 is arranged on the circumferential wall at the bottom of the packaging shell 2. A connecting slot 211 is arranged on the inner wall of one side of the packaging limiting ring 21. An integrally connected ceramic ring 13 is arranged on the outer circumferential wall above the ceramic substrate 1. A plug 131 that is matched and connected with the connecting slot 211 is arranged at the bottom of one side of the ceramic ring 13. A landslide structure 132 is arranged at the top of the side of the ceramic ring 13 away from the plug 131. The top of the ceramic substrate 1 abuts against the inner wall of the top of the packaging shell 2 through a heat-conducting copper tube.

[0028] It should be noted that in this embodiment, the packaging shell 2 is in a hollow structure with an open bottom for accommodating the chips. It is buckled on the ceramic substrate 1, and a packaging limiting ring 21 is arranged on the circumferential wall at the bottom for fixing and positioning. The chips on the ceramic substrate 1 are wrapped and encapsulated by setting the packaging shell 2. An integrally connected ceramic ring 13 is arranged on the outer circumferential wall above the ceramic substrate 1. A plug 131 at the bottom of one side is matched with the connecting slot 211 of the packaging shell 2 to enhance the stability of the connection.

[0029] During connection, first tilt the packaging shell 2 so that the connecting slot 211 opened on the packaging limiting ring 21 at the bottom of the packaging shell 2 is inserted into the plug 131 at the bottom of the ceramic ring 13. Then, simultaneously squeeze the ceramic substrate 1 and the packaging shell 2 from the other side towards the middle, so that the other side of the packaging shell 2 is connected to the ceramic substrate 1 through the landslide structure 132 on the ceramic ring 13. The ceramic substrate 1 abuts and squeezes the packaging shell 2 to make them connected to each other. The structure is simple and the installation is convenient.

[0030] Furthermore, the top of the ceramic substrate 1 abuts against the inner wall of the top of the packaging shell 2 through a heat-conducting copper tube, conducting heat to the packaging shell 2, which is beneficial to thermal management and ensures the performance stability of the sensor when the temperature changes.

[0031] Please refer to Figure 2 、 3And 4, the first sealing component includes a first sealing rubber 3 and a second sealing rubber 4. The first sealing rubber 3 is distributed on the inner circumferential wall inside the encapsulation housing 2. A sealing plugging structure 31 is provided at the bottom of the first sealing rubber 3. The second sealing rubber 4 is located on the ceramic substrate 1 near the outer circumferential wall, and a sealing slot 41 matching the sealing plugging structure 31 is provided on the second sealing rubber 4. The first sealing rubber 3 and the second sealing rubber 4 form an encapsulation cavity for encapsulating and wrapping the chip. The second sealing component includes an elastic heat-shrinkable rubber sleeve 5, and the elastic heat-shrinkable rubber sleeve 5 is sleeved at the connection gap between the encapsulation housing 2 and the ceramic substrate 1.

[0032] It should be noted that in this embodiment, the present application improves the stability and reliability of the MEMS sensor. The sealing structure protects the MEMS sensor from the external environment through multi-layer protection and precise design, ensuring its accuracy and long-term reliability in various applications.

[0033] Furthermore, the first sealing rubber 3 inside the encapsulation housing 2 and the second sealing rubber 4 on the ceramic substrate 1 form an encapsulation cavity through the cooperation of the sealing plugging structure 31 and the sealing slot 41, providing an airtight encapsulation for the chip, preventing external gas or liquid from entering the interior, and ensuring the stability and reliability of the sensor.

[0034] Furthermore, for the first sealing rubber 3 inside the encapsulation housing 2 and the second sealing rubber 4 on the ceramic substrate 1, the outer wall above the first sealing rubber 3 abuts against the inner wall of the encapsulation housing 2, and the bottom of the first sealing rubber 3 is an elastic structure. The bottom of the second sealing rubber 4 on the ceramic substrate 1 abuts against the top of the ceramic substrate 1, and the top of the second sealing rubber 4 is an elastic structure. When the sealing plugging structure 31 on the first sealing rubber 3 is displaced and inserted into the sealing slot 41 of the second sealing rubber 4, the sealing plugging structure 31 and the sealing slot 41 are in sliding contact when they abut against each other. As can be seen from the drawings, the sealing plugging structure 31 and the sealing slot 41 are in mutual force contact and seal each other. The mutual force contact between the sealing plugging structure 31 and the sealing slot 41 ensures the seal between the two, thereby preventing external gas or liquid from entering the encapsulation interior and ensuring the stability and reliability of the sensor.

[0035] Furthermore, the elastic heat-shrinkable rubber sleeve 5 is sleeved at the connection gap between the encapsulation housing 2 and the ceramic substrate 1, and the elastic heat-shrinkable rubber sleeve 5 is heat-shrunk and sealed at the connection gap between the encapsulation housing 2 and the ceramic substrate 1 for secondary sealing.

[0036] The elastic heat-shrinkable rubber sleeve 5 is sealed through a heat-shrinking process. When heat is applied, the rubber sleeve shrinks, thus tightly wrapping around the connection between the encapsulated housing 2 and the ceramic substrate 1. This heat-shrinking rubber sleeve provides a second layer of sealing protection, enhancing the tightness of the overall encapsulation structure and ensuring prevention of any gas or liquid from penetrating into the sensor interior;

[0037] During connection, first tilt the encapsulated housing 2 so that the connection slot 211 opened on the encapsulation limit ring 21 at the bottom of the encapsulated housing 2 is inserted into the insertion rod 131 at the bottom of the ceramic ring 13. At the same time, squeeze the ceramic substrate 1 and the encapsulated housing 2 towards the middle from the other side, so that the other side of the encapsulated housing 2 is connected to the ceramic substrate 1 through the landslide structure 132 on the ceramic ring 13. At this time, the sealing insertion structure 31 on the first sealing rubber 3 is displaced and inserted into the sealing slot 41 of the second sealing rubber 4. The sealing insertion structure 31 and the sealing slot 41 are in sliding contact when inserted, and the sealing insertion structure 31 and the sealing slot 41 are in mutual force contact for mutual sealing. The mutual force contact between the sealing insertion structure 31 and the sealing slot 41 ensures the sealing between the two. Squeeze the ceramic substrate 1 and the encapsulated housing 2 towards the middle at the same time, so that the other side of the encapsulated housing 2 is connected to the ceramic substrate 1 through the landslide structure 132 on the ceramic ring 13. The ceramic substrate 1 abuts and squeezes the encapsulated housing 2 to make them connected to each other. The elastic heat-shrinkable rubber sleeve 5 is sleeved at the connection gap between the encapsulated housing 2 and the ceramic substrate 1. When heat is applied, the rubber sleeve will shrink, thus tightly wrapping around the connection between the encapsulated housing 2 and the ceramic substrate 1.

[0038] The working process of the present utility model:

[0039] When using the connection, first tilt the encapsulation housing 2 so that the connection slot 211 opened on the encapsulation limit ring 21 at the bottom of the encapsulation housing 2 is inserted into the insertion rod 131 at the bottom of the ceramic ring 13. At the same time, squeeze the ceramic substrate 1 and the encapsulation housing 2 towards the middle from the other side, so that the other side of the encapsulation housing 2 is connected to the ceramic substrate 1 through the landslide structure 132 on the ceramic ring 13. At this time, the sealing insertion structure 31 on the first sealing rubber 3 is displaced and inserted into the sealing slot 41 of the second sealing rubber 4. The sealing insertion structure 31 and the sealing slot 41 are in contact and slide inserted. The sealing insertion structure 31 and the sealing slot 41 are in contact with each other under force for mutual sealing. The force between the sealing insertion structure 31 and the sealing slot 41 ensures the sealing between the two, thereby preventing external gas or liquid from entering the encapsulation interior. Squeeze the ceramic substrate 1 and the encapsulation housing 2 towards the middle at the same time, so that the other side of the encapsulation housing 2 is connected to the ceramic substrate 1 through the landslide structure 132 on the ceramic ring 13. The ceramic substrate 1 abuts and squeezes the encapsulation housing 2 to make them connected to each other. The elastic heat-shrinkable rubber sleeve 5 is sleeved at the connection gap between the encapsulation housing 2 and the ceramic substrate 1. When heat is applied, the rubber sleeve will shrink, thus tightly wrapping the connection between the encapsulation housing 2 and the ceramic substrate 1. This heat-shrinkable rubber sleeve provides a second layer of sealing protection, enhancing the sealing performance of the overall encapsulation structure and ensuring the prevention of any gas or liquid from penetrating into the sensor interior.

[0040] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A MEMS sensor sealing structure, comprising a ceramic substrate (1), characterized in that: On one side of the top of the ceramic substrate (1), a MEMS chip (11) is connected and arranged. On the other side of the ceramic substrate (1) on the ceramic substrate (1), an electrical signal chip (12) is arranged. A sealing structure for sealing the chip is arranged on the ceramic substrate (1). The sealing structure includes a packaging shell (2), a first sealing component inside the packaging shell (2), and a second sealing component outside the packaging shell (2).

2. The MEMS sensor sealing structure according to claim 1, wherein: The packaging shell (2) is arranged in a hollow structure with an open bottom to form a receiving cavity for receiving the chip. The packaging shell (2) is buckled on the ceramic substrate (1). A packaging limiting ring (21) is arranged on the circumferential wall of the bottom of the packaging shell (2), and a connecting slot (211) is arranged on the inner wall of one side of the packaging limiting ring (21).

3. The MEMS sensor sealing structure according to claim 2, characterized in that: A ceramic ring (13) integrally connected to the ceramic substrate (1) is arranged on the outer circumferential wall above the ceramic substrate (1). A plug rod (131) matched and connected with the connecting slot (211) is arranged at the bottom of one side of the ceramic ring (13). A landslide structure (132) is arranged at the top of the side of the ceramic ring (13) away from the plug rod (131).

4. A MEMS sensor sealing structure according to claim 1, characterized in that: The first sealing component includes a first sealing rubber (3) and a second sealing rubber (4). The first sealing rubber (3) is distributed on the inner circumferential wall inside the packaging shell (2). A sealing plugging structure (31) is arranged at the bottom of the first sealing rubber (3). The second sealing rubber (4) is located on the ceramic substrate (1) near the outer circumferential wall. A sealing slot (41) matched with the sealing plugging structure (31) is arranged on the second sealing rubber (4). The first sealing rubber (3) and the second sealing rubber (4) form a packaging cavity for packaging and wrapping the chip.

5. A MEMS sensor sealing structure according to claim 1, characterized in that: The second sealing component includes an elastic heat-shrinkable rubber sleeve (5). The elastic heat-shrinkable rubber sleeve (5) is sleeved at the connection gap between the packaging shell (2) and the ceramic substrate (1).

6. A MEMS sensor sealing structure according to claim 1, characterized in that: The top of the ceramic substrate (1) is in contact with the inner wall of the top of the packaging shell (2) through a heat-conducting copper tube.

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