Novel MEMS pressure sensor packaging structure

Abstract

The utility model provides a novel MEMS pressure sensor packaging structure which is good in heat dissipation performance, effectively prevents heat from being accumulated in a chip, and ensures the working stability of the chip. The ASIC chip and the MEMS chip are sequentially installed on the PCB substrate from bottom to top, a base is arranged between the MEMS chip and the PCB substrate, a profiling installation groove matched with the MEMS chip is formed in the top of the base, a heat dissipation cavity is formed in the bottom of the base, and heat dissipation holes communicated with the heat dissipation cavity are formed in the PCB substrate.

Description

Technical Field

[0001] The utility model relates to the technical field of MEMS pressure sensing, in particular to a novel MEMS pressure sensor packaging structure. Background Art

[0002] MEMS sensors are widely used in the fields of barometers, accelerometers, gyroscopes, sensors, etc. MEMS sensors mainly include substrates, MEMS chips, and ASIC chips. However, in the manufacturing process of MEMS sensors, in order to meet the needs of miniaturization and high integration, the substrate, MEMS chip, and ASIC chip are stacked and packaged in sequence to meet the requirements. For example, a MEMS sensor packaging structure published in China with a utility model patent application number of 202223317368.X, however, this method makes the sensor chip accumulate heat during use due to chip stacking, which is difficult to release, thereby causing damage to the components or accelerating aging, and ultimately affecting the stability of the sensor chip. Utility Model Content

[0003] In view of the problem that existing MEMS sensor chips are prone to heat accumulation during use, which is difficult to release, easily causing component damage or accelerated aging, and ultimately affecting the stability of operation, the utility model provides a new MEMS pressure sensor packaging structure with good heat dissipation, which can effectively prevent heat accumulation inside the chip and ensure the stability of chip operation.

[0004] The technical solution is as follows: a novel MEMS pressure sensor packaging structure, which includes a PCB substrate, on which an ASIC chip and a MEMS chip are sequentially mounted from bottom to top, characterized in that a base is provided between the MEMS chip and the PCB substrate, the MEMS chip is arranged above the ASIC chip, a contoured mounting groove matching the ASIC chip is provided on the top of the base, a heat dissipation cavity is provided at the bottom of the base, and a heat dissipation hole connected to the heat dissipation cavity is provided on the PCB substrate.

[0005] It is further characterized in that: the heat dissipation chambers include two, and the PCB substrate is provided with heat dissipation holes respectively connected with the heat dissipation chambers;

[0006] The PCB substrate and the ASIC chip, and the ASIC chip and the MEMS chip are connected by adhesive, and the ASIC chip and the MEMS chip are electrically connected to the pads of the PCB substrate by gold wires respectively;

[0007] The ASIC chip and the MEMS chip are electrically connected to the pads of the PCB substrate through gold wires respectively;

[0008] A cover is also provided on the top of the PCB substrate, and the cover includes a cover plate on the top and a side plate on the side, and the bottom of the side plate is bent outward;

[0009] The cover is filled with potting glue, and the potting glue covers the ASIC chip, the MEMS chip and the gold wire.

[0010] After adopting the above structure, since a base is arranged between the MEMS chip and the PCB substrate, the heat of the chip on the upper end can be transferred to the PCB substrate through the base. At the same time, a heat dissipation cavity is arranged at the bottom of the base. The heat dissipation cavity is connected with the heat dissipation hole of the PCB substrate to further output the heat, thereby effectively preventing heat from accumulating inside the chip and ensuring the stability of the chip operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a sectional view of the overall structure of the utility model. DETAILED DESCRIPTION

[0012] like Figure 1 As shown, a novel MEMS pressure sensor packaging structure includes a PCB substrate 1, on which an ASIC chip 2 and a MEMS chip 3 are sequentially mounted from bottom to top, the PCB substrate 1 and the ASIC chip 2, and the ASIC chip and the MEMS chip 3 are connected by adhesive, and the ASIC chip 2 and the MEMS chip 3 are electrically connected to the pads of the PCB substrate 1 by gold wires. A base 4 is arranged between the MEMS chip 3 and the PCB substrate 1, the top of the base 4 is provided with a contoured mounting groove 41 matching the ASIC chip 2, the bottom of the base 4 is provided with a heat dissipation cavity 42, the heat dissipation cavity 42 can be two, and the PCB substrate 1 is provided with two heat dissipation holes 11 connected with the heat dissipation cavity 42 of the base 4. The heat generated by the ASIC chip 2 and the MEMS chip 3 can be transferred to the PCB substrate 1 through the arrangement of the base 4, and the heat is dissipated to the external environment through the PCB substrate 1. At the same time, since the heat dissipation cavity 42 is arranged at the bottom of the base 4, the heat can be further dissipated through the heat dissipation cavity 42 and the heat dissipation holes 11 of the PCB substrate 1 connected thereto, thereby effectively preventing the heat from accumulating inside the chip and ensuring that the chip can be used normally.

[0013] A cover 5 is also provided on the top of the PCB substrate 1. The cover 5 includes a cover plate on the top and side plates on the sides. The bottom of the side plates is bent outwards.

[0014] The inside of the cover 5 is filled with potting glue 6, which covers the ASIC chip 2, the MEMS chip 3 and the gold wire. The potting glue 6 uses waterproof and anti-corrosion glue to protect the internal chips, prevent water vapor from entering the chip to cause a short circuit, and prevent chip corrosion. The glue has little stress on the chip and has good performance.

[0015] During manufacturing, the ASIC chip 2 is first attached to the corresponding position of the base 4 with adhesive, and baked until the glue is dry and formed, and the ASIC chip 2 is wired, that is, the input and output of the ASIC chip 2 are connected to the external pins with gold wires, and then the MEMS chip 3 is attached to the top of the ASIC chip 3 with adhesive. After baking, the MEMS chip is wired again, and protective glue 6 is poured on the outer surface of the chip to prevent water vapor and corrosion. Finally, the cover 5 is attached to the edge of the PCB substrate 1 with adhesive to form a closed space. The glue is cured through the baking process to make it sealed, and after reflow aging, the stress of the product shell and the chip is released.

[0016] The above are only preferred specific implementations of the utility model, but the protection scope of the utility model is not limited thereto. Any changes or substitutions that can be easily thought of by anyone familiar with the technology within the technical scope disclosed by the utility model should be included in the protection scope of the utility model. Therefore, the protection scope of the utility model should be based on the protection scope of the claims.

Claims

1. A novel MEMS pressure sensor packaging structure, comprising a PCB substrate, on which an ASIC chip and a MEMS chip are sequentially mounted from bottom to top, characterized in that: A base is arranged between the MEMS chip and the PCB substrate, a contoured mounting groove matching the ASIC chip is arranged on the top of the base, a heat dissipation cavity is arranged at the bottom of the base, and a heat dissipation hole communicating with the heat dissipation cavity is arranged on the PCB substrate.

2. A novel MEMS pressure sensor packaging structure according to claim 1, characterized in that: The heat dissipation chambers include two, and the PCB substrate is provided with heat dissipation holes respectively connected with the heat dissipation chambers.

3. The novel MEMS pressure sensor packaging structure according to claim 2 is characterized in that: The PCB substrate and the ASIC chip, and the ASIC chip and the MEMS chip are connected by adhesive, and the ASIC chip and the MEMS chip are electrically connected to the pads of the PCB substrate by gold wires respectively.

4. The novel MEMS pressure sensor packaging structure according to claim 3 is characterized in that: A sealing cover is also provided on the top of the PCB substrate, and the sealing cover includes a cover plate on the top and side plates on the side, and the bottom of the side plate is bent outward.

5. The novel MEMS pressure sensor packaging structure according to claim 4 is characterized in that: The cover is filled with potting glue, and the potting glue covers the ASIC chip, the MEMS chip and the gold wire.

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