CN211656378U

CN211656378U - MEMS chip assembly

Info

Publication number: CN211656378U
Application number: CN202020211935.5U
Authority: CN
Inventors: 柏杨
Original assignee: AAC Acoustic Technologies Shenzhen Co Ltd
Current assignee: AAC Technologies Holdings Shenzhen Co Ltd
Priority date: 2020-02-25
Filing date: 2020-02-25
Publication date: 2020-10-09
Anticipated expiration: 2030-02-25
Also published as: WO2021168902A1

Abstract

The utility model provides a MEMS chip subassembly, MEMS chip subassembly include the base plate and install in MEMS chip on the base plate, MEMS chip including the basement that has the cavity and set up in sensing portion on the base member, the MEMS chip is located through the glue subsides the base plate, the basement is including enclosing and establishing into the inner wall of cavity, the basement still includes certainly the inner wall to the glue barrier layer of the inside extension of cavity. The utility model discloses can prevent effectively that the paster from gluing excessive to MEMS chip top on water, avoid glue to pollute the microphone performance inefficacy that the vibrating diaphragm caused. Moreover, the glue barrier layer can increase the combination area of the glue and the bottom of the MEMS chip, so that the MEMS chip is more firmly connected with the substrate, the resistance of the microphone device to falling and vibration is enhanced, and the reliability is improved.

Description

MEMS chip assembly

[ technical field ] A method for producing a semiconductor device

The utility model belongs to the technical field of the microphone, especially, relate to a MEMS chip subassembly.

[ background of the invention ]

An MEMS (Micro-Electro-Mechanical System) microphone is an electric transducer manufactured by using a micromachining technology, and has the characteristics of small volume, good frequency response characteristics, low noise and the like. With the development of miniaturization and lightness of electronic devices, MEMS microphones are increasingly widely used for these devices. The MEMS chip in the MEMS microphone device plays an important role as a signal sensing part, the MEMS chip is usually fixed on a packaging substrate by a surface mounting process in the packaging process of the MEMS microphone, and the stability of the MEMS chip on the substrate is realized through glue in a connecting mode.

In the related art, during the processing of the MEMS chip, a cavity of the MEMS chip substrate is often formed by dry etching, the size of the open cavity is large at the top and small at the bottom, and the cross section of the substrate forms an acute angle. In the actual packaging process, the patch glue easily overflows to the diaphragm part on the upper part of the MEMS chip from the bottom of the MEMS chip along the cavity wall, and the overflow phenomenon of the glue is more serious due to the acute angle. For a condenser microphone, a piezoelectric microphone and an optical microphone, the diaphragm of the chip is sensitive to flowing liquid, and the diaphragm deformation caused by the overflow of glue can further cause the change of the output signal of the MEMS chip, thereby seriously affecting the performance of a microphone device.

[ Utility model ] content

An object of the utility model is to provide a MEMS chip subassembly aims at preventing that the paster from gluing excessive to MEMS chip top on water, has avoided glue to pollute the microphone performance inefficacy that the vibrating diaphragm caused.

The technical scheme of the utility model as follows: the utility model provides a MEMS chip subassembly, its includes the base plate and install in MEMS chip on the base plate, MEMS chip including the basement that has the cavity and set up in sensing portion on the base member, MEMS chip passes through the glue and pastes and locates the base plate, the basement is including enclosing and establish the inner wall of cavity, the basement still includes certainly the inner wall to the inside glue barrier layer that extends of cavity.

Further, the glue barrier layer is a plurality of block-shaped structures arranged at intervals along the circumferential direction of the inner wall.

Further, the glue barrier layer is an annular structure arranged around the circumferential direction of the inner wall.

Further, the sensing part is a capacitive structure, a piezoelectric structure, or an optical sensor.

Further, the substrate comprises a substrate top surface fixed with the sensing part and a substrate bottom surface opposite to the substrate top surface, the size of the cavity is gradually reduced from the substrate top surface to the substrate bottom surface, and the cross-sectional area of the cavity at the position of the glue barrier layer is smaller than that of the cavity at the position of the substrate bottom surface.

Further, a glue blocking layer is arranged in the cavity.

Furthermore, a plurality of glue blocking layers are arranged in the cavity at intervals.

The beneficial effects of the utility model reside in that: through setting up the glue barrier layer, can prevent effectively that the paster from gluing excessive to MEMS chip top on water, avoid glue to pollute the microphone performance inefficacy that the vibrating diaphragm caused. Moreover, the glue blocking layer can increase the combination area of the glue and the bottom of the MEMS chip, so that the MEMS chip is more firmly connected with the substrate, the drop and vibration resisting capacity of the microphone device is enhanced, and the reliability is improved.

[ description of the drawings ]

Fig. 1 is a schematic cross-sectional structural diagram of a MEMS chip assembly provided in an embodiment of the present invention;

fig. 2 is a schematic cross-sectional structure diagram of another embodiment of a MEMS chip assembly according to an embodiment of the present invention.

[ detailed description ] embodiments

The present invention will be further described with reference to the accompanying drawings and embodiments.

Example (b):

referring to fig. 1, fig. 1 is a diagram of a MEMS chip assembly according to an embodiment of the present invention, including a substrate 20 and a MEMS chip 10 mounted on the substrate 20, the MEMS chip 10 includes a base 1 having a cavity 3 and a sensing portion 2 disposed on the base 1, and the MEMS chip 10 is attached to the substrate 20 through glue.

The sensing part 2 is a capacitive structure, a piezoelectric structure, or an optical sensor. Based on different acoustoelectric conversion principles, the sensing part 2 can be selected to be different structures, the piezoelectric structure senses by directly picking up physical vibration of a sound source, and the optical sensor senses by collecting vibration signals in a specified range. As shown in fig. 1, the sensing portion 2 of the MEMS chip 10 of the present embodiment is a capacitor structure, and includes a diaphragm 22 fixed to the substrate 1 and a back plate 21 spaced apart from the diaphragm 22. The capacitor structure changes the distance between the diaphragm 22 and the back plate 21 according to the received sound signal, thereby outputting a corresponding electrical signal.

In this embodiment, the substrate 1 includes an inner wall 11 enclosing the cavity 3, and the substrate 1 further includes a glue barrier layer 12 extending from the inner wall 11 to the inside of the cavity 3. By providing the glue blocking layer 12, it is possible to effectively prevent the patch glue from overflowing to the top of the MEMS chip 10, and avoid the microphone performance failure caused by the contamination of the diaphragm 22 by the glue, compared with the related art. Moreover, the glue barrier layer 12 can increase the bonding area between the glue and the bottom of the MEMS chip 10, so that the connection between the MEMS chip 10 and the substrate 20 is firmer, the drop and vibration resistance of the microphone device is enhanced, and the reliability is improved.

Preferably, the glue barrier layer 12 is a plurality of spaced block structures circumferentially arranged along the inner wall 11, and the plurality of block glue barrier layers 12 circumferentially arranged can play a better blocking role for glue, so as to effectively prevent the patch glue from overflowing to the top of the MEMS chip 10. In other embodiments, the glue barrier layer 12 may also be an annular structure circumferentially disposed around the inner wall 11. Further, the substrate 1 includes a top substrate surface 13 fixed to the sensing portion 2 and a bottom substrate surface 14 opposite to the top substrate surface 13, and the size of the cavity 3 gradually decreases from the top substrate surface 13 to the bottom substrate surface 14, that is, the cavity 3 as a whole takes a shape with a large top and a small bottom, and the thickness of the inner wall 11 closer to the bottom is larger, the area of the bottom substrate surface 14 is larger, so that the MEMS chip 10 and the substrate 20 are fixed more firmly. The cross-sectional area of the cavity 3 at the location of the glue barrier layer 12 is smaller than the cross-sectional area of the cavity 3 at the location of the base bottom surface 14, i.e. the projection of the glue barrier layer 12 on the substrate 20 is closer to the center of the cavity than the projection of the edge of the base bottom surface 14 on the substrate 20. The thickness of the glue barrier layer 12 should not be too large, otherwise the inner space of the cavity 3 would be reduced, thereby affecting the performance of the microphone.

In an implementation manner of the embodiment of the present invention, a glue blocking layer 12 is disposed in the cavity 3. In another embodiment of the present invention, as shown in fig. 2, a multilayer glue blocking layer 12 is disposed in the cavity 3, and the multilayer glue blocking layer 12 is spaced from each other, so as to further enhance the blocking effect of the glue blocking layer 12 on the glue.

To sum up, the embodiment of the utility model provides a MEMS chip subassembly through setting up glue barrier layer 12, can prevent effectively that the paster from gluing excessive to MEMS chip 10 top on water, has avoided glue to pollute the microphone performance inefficacy that vibrating diaphragm 22 caused. Moreover, the glue blocking layer can increase the bonding area of the glue and the bottom of the MEMS chip 10, so that the connection between the MEMS chip 10 and the substrate 20 is firmer, the drop and vibration resistance of the microphone device is enhanced, and the reliability is improved.

The above embodiments of the present invention are only described, and it should be noted that, for those skilled in the art, modifications can be made without departing from the inventive concept, but these all fall into the protection scope of the present invention.

Claims

1. The utility model provides a MEMS chip subassembly, its includes the base plate and install in MEMS chip on the base plate, MEMS chip including the basement that has the cavity and set up in sensing portion on the basement, MEMS chip pastes through the glue and locates the base plate, the basement is including enclosing and establish into the inner wall of cavity, its characterized in that: the substrate further includes a glue barrier layer extending from the inner wall into the cavity.

2. The MEMS chip assembly of claim 1, wherein the glue barrier is a plurality of spaced-apart block-like structures disposed circumferentially along the inner wall.

3. The MEMS chip assembly of claim 1, wherein the glue barrier layer is an annular structure circumferentially disposed around the inner wall.

4. The MEMS chip assembly of claim 1, wherein the sensing portion is a capacitive structure, a piezoelectric structure, or an optical sensor.

5. The MEMS chip assembly of claim 2 or 3, wherein the substrate comprises a top substrate surface fixed to the sensing portion and a bottom substrate surface opposite to the top substrate surface, the cavity has a size gradually decreasing from the top substrate surface to the bottom substrate surface, and a cross-sectional area of the cavity at the location of the glue barrier is smaller than a cross-sectional area of the cavity at the location of the bottom substrate surface.

6. The MEMS chip assembly of claim 2 or 3, wherein a glue barrier layer is disposed within the cavity.

7. The MEMS chip assembly of claim 2 or 3, wherein a plurality of spaced glue barrier layers are disposed within the cavity.