CN215364898U

CN215364898U - MEMS inertial sensor chip module and MEMS sensor

Info

Publication number: CN215364898U
Application number: CN202121621591.6U
Authority: CN
Inventors: 虢晓双; 杨靖; 张新凯; 熊亮; 黎傲雪; 彭健
Original assignee: Hunan Navigate Technology Co ltd
Current assignee: Hunan Navigate Technology Co ltd
Priority date: 2021-07-16
Filing date: 2021-07-16
Publication date: 2021-12-31
Anticipated expiration: 2031-07-16

Abstract

The utility model discloses an MEMS (micro electro mechanical system) inertial sensor chip module and an MEMS sensor, which comprise a shell, wherein the shell is respectively fixed with a PCB (printed circuit board) and a metal supporting column, an MEMS inertial sensor chip component is supported on the metal supporting column, and a connecting terminal on the MEMS inertial sensor chip component is mutually connected with a connecting terminal on the PCB through a metal wire. The utility model does not need a primary packaging process, greatly reduces the packaging and integration cost, reduces the integration volume, avoids the thermal stress involved in surface mounting, can realize quick heat conduction, can keep various performance indexes of the MEMS inertial sensor chip level, can improve the application limit of the prior art to the MEMS inertial sensor chip, and avoids the influence of the primary packaging or secondary packaging thermal stress on the system integration application.

Description

MEMS inertial sensor chip module and MEMS sensor

Technical Field

The utility model relates to a semiconductor device, in particular to an MEMS (micro-electromechanical systems) inertial sensor chip module which is used for integrated assembly of inertial sensor chips such as MEMS gyroscopes, MEMS accelerometers and the like.

Background

The inertial sensor based on the MEMS technology has the advantages of light weight, low cost, small volume, mass production and the like, and has extremely wide application and development prospects in the fields of civil use, aerospace and military; before the MEMS inertial sensor chip is assembled in an integrated mode, the MEMS inertial sensor chip is firstly mounted on a PCB (printed circuit board) or other substrates together with passive components (secondary packaging mode) through the primary packaging modes such as ceramic tube shell packaging, plastic packaging, ceramic substrate COB packaging and the like by adopting the Surface Mounting Technology (SMT), the direct chip mounting technology (DCA), the through hole mounting technology (THT) and the like, so that the MEMS inertial sensor chip becomes a part or a whole machine, and the whole process is relatively complex; or the surface mounting is carried out by adopting low-temperature solder paste, but the subsequent process is not facilitated.

In the primary packaging process and the secondary packaging process, thermal stress and welding stress are easily caused due to large difference of Coefficient of Thermal Expansion (CTE) between materials, and the MEMS inertial sensor chip is easily influenced by the packaging stress and the welding stress, especially the full-temperature characteristic index; in single chip integrated package, an ASIC and an MEMS chip are often stacked, and the heat generated by the ASIC may also affect the output performance of the MEMS; in addition, the die sinking or self processing of the ceramic tube shell, the ceramic substrate, the plastic tube shell and the like has relatively high manufacturing cost and no universality, the volume of the chip is obviously increased by several times or even more than that of the chip, and the volume contradiction is particularly obvious in the integration application of an Inertial Measurement Unit (IMU).

SUMMERY OF THE UTILITY MODEL

The technical problems to be solved by the utility model are as follows: aiming at the problems in the prior art, the utility model provides an MEMS inertial sensor chip module, which does not need a primary packaging process, greatly reduces the packaging and integration cost, reduces the integration volume, avoids the thermal stress involved in surface mounting, can also realize rapid heat conduction, can keep various performance indexes of the MEMS inertial sensor chip level, can improve the application limit of the prior art on the MEMS inertial sensor chip, and avoids the influence of the thermal stress of primary packaging or secondary packaging on the system integration application.

In order to solve the technical problems, the utility model adopts the technical scheme that:

the utility model provides a MEMS inertial sensor chip module, includes the casing, the casing is fixed with PCB board and metal support post respectively, the last support of metal support post has MEMS inertial sensor chip subassembly, connecting terminal on the MEMS inertial sensor chip subassembly passes through metal wire and PCB board on connecting terminal interconnect.

The MEMS inertial sensor chip assembly comprises an MEMS inertial sensor chip and a substrate which has the same and similar thermal expansion coefficient with the MEMS inertial sensor chip, the MEMS inertial sensor chip is fixed on the substrate, and the substrate is supported and fixed on the end face of the metal supporting column.

And the substrate is also provided with an AISC circuit chip for preprocessing the output of the MEMS inertial sensor chip.

The PCB is provided with a through hole, and the metal support columns penetrate through the through hole to be arranged, so that the PCB and the MEMS inertial sensor chip assembly are arranged in parallel.

The casing includes upper cover, main shell and sealing washer, link to each other through the connecting piece between upper cover, the main shell, just the sealing washer is arranged between the terminal surface of upper cover, main shell, the metal support post is pasted and is fixed on the inner wall of upper cover or main shell.

The metal wire is a gold wire formed in a gold wire ball bonding mode.

The upper cover and the main shell are made of ceramics or metal.

The substrate is made of silicon material or glass material.

The metal supporting column is made of tungsten-copper alloy.

The MEMS sensor comprises a sensor body and an MEMS inertial sensor chip module arranged in the sensor body, wherein the MEMS inertial sensor chip module is the MEMS inertial sensor chip module.

Compared with the prior art, the MEMS inertial sensor chip module has the following advantages:

1. the MEMS inertial sensor chip component can adopt a monocrystalline silicon substrate to modularize a single-piece MEMS sensor chip or close and seal the MEMS sensor chip and an ASIC circuit, does not need a primary packaging process, greatly reduces packaging and integration cost, reduces integration volume, can improve the application limit of the prior art to the MEMS inertial sensor chip, and avoids the influence of thermal stress of primary packaging or secondary packaging on system integration application.

2. The shell is respectively fixed with the PCB and the metal supporting columns, the MEMS inertial sensor chip assembly is supported on the metal supporting columns and is fixedly attached to the shell through the metal supporting columns, so that the MEMS inertial sensor chip assembly forms a suspension isolation scheme and is directly connected with the PCB through gold wire bonding, the thermal stress involved in surface mounting is avoided, and the rapid heat conduction can be realized, so that various performance indexes of the MEMS inertial sensor chip level can be maintained.

3. The metal support column can play a role in heat conduction, so that heat accumulation of the MEMS inertial sensor chip assembly is prevented, and the precision of the MEMS inertial sensor chip assembly is improved.

Drawings

Fig. 1 is a schematic perspective exploded view of a MEMS inertial sensor chip module according to this embodiment.

Fig. 2 is a schematic perspective view of a MEMS inertial sensor chip assembly according to the present embodiment.

Fig. 3 is a schematic external structural diagram of the MEMS inertial sensor chip module according to the present embodiment.

Fig. 4 is a schematic cross-sectional structural view of a MEMS inertial sensor chip assembly according to this embodiment.

Fig. 5 is a schematic diagram of connection pins of the MEMS inertial sensor chip and the AISC circuit chip in this embodiment.

FIG. 6 is a 10s smooth curve of the full temperature zero offset bias stability of a 15g accelerometer module assembly sample of this embodiment.

FIG. 7 is a 10s smooth curve of the full temperature zero offset bias stability of a 15g non-modular assembled sample of the accelerometer of this embodiment.

FIG. 8 is a temperature curve of the temperature compensation of the sample oven assembled with a 15g accelerometer module according to the present embodiment.

Fig. 9 is a comparison chart of the temperature increase and decrease of a certain 15g accelerometer module #2 in this embodiment.

Fig. 10 is a comparison chart of the temperature increase and decrease of a 15g accelerometer non-module #2 in the present embodiment.

Fig. 11 is a table of data records of temperature compensation effect of samples assembled by an accelerometer module in this embodiment.

Illustration of the drawings: 1. a housing; 11. an upper cover; 12. a main housing; 13. a seal ring; 2. a PCB board; 21. a via hole; 3. a metal support post; 4. a MEMS inertial sensor chip assembly; 41. an MEMS inertial sensor chip; 42. a substrate; 43. AISC circuit chip.

Detailed Description

As shown in fig. 1, 2 and 3, the MEMS inertial sensor chip module of the present embodiment includes a housing 1, the housing 1 is respectively fixed with a PCB 2 and a metal supporting pillar 3, the metal supporting pillar 3 supports a MEMS inertial sensor chip assembly 4, and a connecting terminal on the MEMS inertial sensor chip assembly 4 is connected to a connecting terminal on the PCB 2 through a metal wire.

As shown in fig. 1, 2 and 4, in the present embodiment, the MEMS inertial sensor chip assembly 4 includes a MEMS inertial sensor chip 41 and a substrate 42 having the same thermal expansion coefficient as that of the MEMS inertial sensor chip 41, the MEMS inertial sensor chip 41 is fixed on the substrate 42, and the substrate 42 is supported and fixed on the end face of the metal supporting pillar 3.

It should be noted that the MEMS inertial sensor chip assembly 4 may adopt a single crystal silicon substrate to modularize a single-attached MEMS sensor chip or to close and seal the MEMS sensor chip and the ASIC circuit. For example, as an alternative implementation, as shown in fig. 1, in this embodiment, an AISC circuit chip 43 for performing pre-processing on the output of the MEMS inertial sensor chip 41 is further disposed on the substrate 42, the AISC circuit chip 43 specifically adopts an ACC1904B chip, and the pin connections are as shown in fig. 5.

As shown in fig. 1 and 4, in the present embodiment, a via hole 21 is formed on the PCB board 2, and the metal supporting pillar 3 is disposed through the via hole 21, so that the PCB board 2 and the MEMS inertial sensor chip assembly 4 are disposed in parallel with each other. The metal support column 3 isolates the MEMS inertial sensor chip component 4 from the PCB 2 through the PCB 2 with the through hole 21, and various chips on the MEMS inertial sensor chip component 4 are interconnected with the PCB 2 through metal wires.

As shown in fig. 4, in this embodiment, the metal support column 3 is connected to the back surface of the AISC circuit chip 43 region on the substrate 42, which is beneficial to improving the heat dissipation effect on the AISC circuit chip 43.

As shown in fig. 1, 3 and 4, in this embodiment, the housing 1 includes an upper cover 11, a main shell 12 and a sealing ring 13, the upper cover 11 and the main shell 12 are connected through a connecting member, the sealing ring 13 is disposed between end surfaces of the upper cover 11 and the main shell 12, and the metal support column 3 is fixed to an inner wall of the upper cover 11 or the main shell 12 (specifically, the high thermal conductivity silver paste is fixed to the inner wall of the main shell 12 in this embodiment).

In this embodiment, the metal wire is a gold wire formed by gold wire ball bonding, and the specific specification is 1 mil.

The upper cover 11 and the main casing 12 may be made of ceramic or metal, for example, aluminum alloy in this embodiment, as required.

The substrate 42 may be made of silicon or glass having a thermal expansion coefficient similar to that of the MEMS inertial sensor chip 41 as required. For example, in the embodiment, the substrate 42 is made of a prex7740 glass material.

In this embodiment, the metal supporting column 3 is made of tungsten-copper alloy.

The preparation method of the MEMS inertial sensor chip module of the present embodiment includes the steps of:

1) welding components of the PCB 2, installing and fixing the components on the main shell 12;

2) cutting out a substrate 42 by using a nanosecond laser cutting machine and cleaning (in the embodiment, cleaning is performed by using a semiconductor wafer standard cleaning process), depositing a metal conducting layer on the surface of the substrate 42 by using a magnetron sputtering method (connection terminals of chips on the substrate are connected with an external circuit and processed), adhering the MEMS inertial sensor chip 41 and the AISC circuit chip 43 to the substrate 42 by using conductive silver paste, drying and curing to obtain an MEMS inertial sensor chip assembly 4; adhering the MEMS inertial sensor chip component 4 to the metal support column 3, and drying and curing; the metal support column 3 penetrates through a through hole 21 on the PCB 2, is adhered to the inner wall of the main shell 12 by high-thermal-conductivity silver adhesive and is cured at high temperature;

3) connecting a connecting terminal on the MEMS inertial sensor chip component 4 with a connecting terminal on the PCB 2 in a gold wire ball bonding mode; the integrated module is interconnected with the PCB in a gold wire direct routing mode, so that the influence of secondary packaging welding stress is directly avoided, and the whole interconnection process is simpler;

4) the main shell 12 is placed in a nitrogen-filled environment, the upper cover 11 and the main shell 12 are connected through a connecting piece, the sealing ring 13 is arranged between the end faces of the upper cover 11 and the main shell 12 to obtain the shell 1, and the edge gap of the assembled shell 1 is sealed by vacuum sealing glue.

During this module integrated assembly, MEMS inertial sensor chip 41, AISC circuit chip 43 adopt the tiling mode to paste to base plate 42 on, metal support column 3 adopts the tungsten-copper alloy material, so can go out AISC circuit chip 43 heat conduction fast, also can avoid the heat direct effect to MEMS inertial sensor chip 41 simultaneously.

In this embodiment, a 15g accelerometer is used to implement the performance test of the whole temperature region of the whole machine, the module is a sample using the MEMS inertial sensor chip module of this embodiment, and the non-module is a sample not using the MEMS inertial sensor chip module of this embodiment, and the comparative tests are shown in fig. 6, 7, 8, 10, and 11. Fig. 6 is a 10s smooth curve of the full-temperature zero-offset bias stability of a 15g accelerometer module assembly sample in this embodiment, fig. 7 is a 10s smooth curve of the full-temperature zero-offset bias stability of a 15g accelerometer non-module assembly sample in this embodiment, fig. 8 is a temperature compensation temperature curve graph of a 15g accelerometer module assembly sample incubator in this embodiment, fig. 9 is a comparison graph before and after temperature compensation for a 15g accelerometer module #2 in this embodiment, fig. 10 is a comparison graph before and after temperature compensation for a 15g accelerometer non-module #2 in this embodiment, and fig. 11 is a temperature compensation effect data recording table of a certain accelerometer module assembly sample in this embodiment. As can be seen from comparison of fig. 6 to 11, the 10s smooth data curve of the bias stability of the full temperature zone of the sample adopting the MEMS inertial sensor chip module of the present embodiment is smooth, the temperature hysteresis phenomenon does not occur in the temperature range of-40 ℃ to 60 ℃, the data collection points of the full temperature zone do not have obvious abnormal fluctuation points, and the repeatability of the multi-round test is good; the sample which does not adopt the MEMS inertial sensor chip module of the embodiment is directly packaged by adopting a ceramic or metal tube shell, the secondary packaging surface is attached to the sample of the PCB, and the bias stability 10s smooth data curve of the full temperature zone has obvious temperature hysteresis effect and zero disconnection phenomenon; the temperature compensation effect and the overall consistency and stability of the temperature compensation sample of the sample adopting the MEMS inertial sensor chip module are obviously superior to those of a sample adhered to a PCB (printed circuit board) by ceramic or metal tube package or ceramic or metal substrate package.

In addition, this embodiment still provides a MEMS sensor, including the sensor body with locate the MEMS inertial sensor chip module in the sensor body, the MEMS inertial sensor chip module is aforementioned MEMS inertial sensor chip module, this MEMS sensor can be MEMS sensors such as MEMS gyroscope, MEMS accelerometer.

The above description is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments, and all technical solutions belonging to the idea of the present invention belong to the protection scope of the present invention. It should be noted that modifications and embellishments within the scope of the utility model may occur to those skilled in the art without departing from the principle of the utility model, and are considered to be within the scope of the utility model.

Claims

1. The utility model provides a MEMS inertial sensor chip module, its characterized in that, includes casing (1), casing (1) is fixed with PCB board (2) and metal support post (3) respectively, the support has MEMS inertial sensor chip subassembly (4) on metal support post (3), connecting terminal on the MEMS inertial sensor chip subassembly (4) passes through the connecting terminal interconnect on metal wire and the PCB board (2).

2. The MEMS inertial sensor chip module according to claim 1, wherein the MEMS inertial sensor chip assembly (4) comprises a MEMS inertial sensor chip (41) and a substrate (42) having a thermal expansion coefficient similar to that of the MEMS inertial sensor chip (41), the MEMS inertial sensor chip (41) is fixed on the substrate (42), and the substrate (42) is supported and fixed on an end face of the metal supporting pillar (3).

3. The MEMS inertial sensor chip module according to claim 2, characterized in that the substrate (42) is further provided with an AISC circuit chip (43) for pre-processing the output of the MEMS inertial sensor chip (41).

4. The MEMS inertial sensor chip module according to claim 3, characterized in that the PCB board (2) is provided with vias (21), and the metal support posts (3) are arranged through the vias (21) such that both the PCB board (2) and the MEMS inertial sensor chip assembly (4) are arranged parallel to each other.

5. The MEMS inertial sensor chip module according to claim 4, wherein the housing (1) comprises an upper cover (11), a main shell (12) and a sealing ring (13), the upper cover (11) and the main shell (12) are connected through a connecting member, the sealing ring (13) is arranged between the end surfaces of the upper cover (11) and the main shell (12), and the metal supporting column (3) is fixed on the inner wall of the upper cover (11) or the main shell (12) in an adhering manner.

6. The MEMS inertial sensor chip module according to claim 5, wherein the metal wire is a gold wire formed by gold wire ball bonding.

7. The MEMS inertial sensor chip module according to claim 6, characterized in that the upper cover (11), the main shell (12) are made of ceramic or metal.

8. The MEMS inertial sensor die set according to claim 7, characterized in that the substrate (42) is made of silicon or glass.

9. The MEMS inertial sensor chip module according to claim 8, characterized in that the metal support posts (3) are made of tungsten-copper alloy.

10. A MEMS sensor, comprising a sensor body and a MEMS inertial sensor die set disposed in the sensor body, wherein the MEMS inertial sensor die set is the MEMS inertial sensor die set according to any one of claims 1 to 9.