阅读说明：本技术 异质集成表贴陀螺 (Heterogeneous integrated surface-mounted gyroscope ) 是由 尚帅 裴志强 褚伟航 郄立伟 赵黎明 王天宇 张琳琳 于 2021-11-22 设计创作，主要内容包括：本发明提供一种异质集成表贴陀螺,包括底板、MEMS陀螺芯片和盖板,所述底板的正面设置有凸台,所述凸台上设置有芯片电极,所述底板的背面设置有多个与所述芯片电极电连接的第一电极；所述MEMS陀螺芯片的有源区焊接在所述凸台上、并通过凸点电极与所述芯片电极电连接；所述盖板封装在所述底板的正面,且所述盖板与所述底板之间留有真空空腔,所述MEMS陀螺芯片位于所述真空空腔内。MEMS陀螺芯片通过倒扣的方式焊接在凸台上,并且,底板和盖板将MEMS陀螺芯片封装,实现了石英MEMS陀螺的表贴封装,可以在不损失石英MEMS陀螺性能的情况下实现体积的微型化,更易于实现集成化。(The invention provides a heterogeneous integrated surface-mounted gyroscope which comprises a bottom plate, an MEMS gyroscope chip and a cover plate, wherein a boss is arranged on the front surface of the bottom plate, a chip electrode is arranged on the boss, and a plurality of first electrodes electrically connected with the chip electrode are arranged on the back surface of the bottom plate; the active area of the MEMS gyroscope chip is welded on the boss and is electrically connected with the chip electrode through a bump electrode; the cover plate is packaged on the front face of the bottom plate, a vacuum cavity is reserved between the cover plate and the bottom plate, and the MEMS gyroscope chip is located in the vacuum cavity. The MEMS gyroscope chip is welded on the boss in an inverted buckle mode, the base plate and the cover plate package the MEMS gyroscope chip, surface-mounted package of the quartz MEMS gyroscope is achieved, miniaturization of the size can be achieved under the condition that performance of the quartz MEMS gyroscope is not lost, and integration is easier to achieve.)

1. A heterogeneous integrated surface mount gyroscope, comprising:

the front surface of the bottom plate is provided with a boss, a chip electrode is arranged on the boss, and the back surface of the bottom plate is provided with a plurality of first electrodes electrically connected with the chip electrode;

the active area of the MEMS gyro chip is welded on the boss and is electrically connected with the chip electrode through a bump electrode;

the cover plate is packaged on the front face of the base plate, a vacuum cavity is reserved between the cover plate and the base plate, and the MEMS gyroscope chip is located in the vacuum cavity.

2. The heterogeneous integrated surface-mounted gyroscope of claim 1, wherein at least two ground electrodes surrounding the bosses are arranged in the vacuum cavity, and a second electrode electrically connected with the ground electrodes is arranged on the back surface of the bottom plate.

3. The heterogeneous integrated surface mount gyroscope of claim 1, wherein the base plate is further provided with:

a plurality of first connection electrodes for connecting the first electrodes and the chip electrodes;

the plurality of first through holes are used for the first connecting electrodes to pass through, and the plurality of first through holes correspond to the plurality of first connecting electrodes one to one.

4. The heterogeneous integrated surface-mounted gyroscope of claim 2, wherein the base plate is further provided with:

at least two second connection electrodes for connecting the ground electrode and the second electrodes;

and at least two second through holes for the second connection electrodes to pass through.

5. The heterogeneous integrated surface-mounted gyroscope of claim 1, wherein the front face of the bottom plate is provided with an annular groove, and the annular groove is disposed around the boss.

6. The heterogeneous integrated surface-mounted gyroscope of claim 5, wherein the bottom surface of the cover plate is provided with a concave pit, and the concave pit is correspondingly connected with the annular groove to form the vacuum cavity.

7. The heterogeneous integrated surface-mounted gyroscope of claim 5, wherein the front surface of the bottom plate is provided with an insulating medium layer, and the insulating medium layer is positioned at the periphery of the annular groove or the boss.

8. The heterogeneous integrated surface-mounted gyroscope of claim 7, wherein a first bonding layer is disposed above the insulating medium layer, and a second bonding layer for bonding with the first bonding layer is disposed on the bottom surface of the cover plate.

9. The heterogeneous integrated surface-mounted gyroscope of claim 1, wherein the base plate is a high-resistance silicon base plate and the cover plate is a low-resistance silicon cover plate.

10. The heterogeneous integrated surface-mounted gyroscope of claim 8, wherein the first bonding layer and the second bonding layer are both made of metal;

or, one of the first bonding layer and the second bonding layer is made of metal, and the other one of the first bonding layer and the second bonding layer is made of silicon;

or the first bonding layer and the second bonding layer are both made of inorganic non-metallic materials.

Technical Field

The invention relates to the technical field of gyroscopes, in particular to a heterogeneous integrated surface-mounted gyroscope.

Background

The MEMS gyroscope is widely used in inertial navigation systems in industries such as consumer electronics, aerospace, and automotive industries because of its small size and easy integration. Among them, the quartz MEMS gyroscope is very popular with users due to its good stability and high performance. However, the traditional quartz MEMS gyroscope is difficult to further reduce in volume due to the particularity of bonding packaging, and further development of the traditional quartz MEMS gyroscope is limited.

Disclosure of Invention

The invention provides a heterogeneous integrated surface-mounted gyroscope, which is used for solving the defect that the size of a quartz MEMS gyroscope is difficult to further reduce due to the particularity of bonding packaging in the prior art.

The invention provides a heterogeneous integrated surface-mounted gyroscope, which comprises:

the front surface of the bottom plate is provided with a boss, a chip electrode is arranged on the boss, and the back surface of the bottom plate is provided with a plurality of first electrodes electrically connected with the chip electrode;

the active area of the MEMS gyro chip is welded on the boss and is electrically connected with the chip electrode through a bump electrode;

the cover plate is packaged on the front face of the base plate, a vacuum cavity is reserved between the cover plate and the base plate, and the MEMS gyroscope chip is located in the vacuum cavity.

According to the heterogeneous integrated surface-mounted gyroscope provided by the invention, at least two ground electrodes surrounding the lug boss are arranged in the vacuum cavity, and the back surface of the bottom plate is provided with a second electrode electrically connected with the ground electrodes.

According to the heterogeneous integrated surface-mounted gyroscope provided by the invention, the bottom plate is further provided with:

a plurality of first connection electrodes for connecting the first electrodes and the chip electrodes;

the plurality of first through holes are used for the first connecting electrodes to pass through, and the plurality of first through holes correspond to the plurality of first connecting electrodes one to one.

According to the heterogeneous integrated surface-mounted gyroscope provided by the invention, the bottom plate is also provided with:

at least two second connection electrodes for connecting the ground electrode and the second electrodes;

and at least two second through holes for the second connection electrodes to pass through.

According to the heterogeneous integrated surface-mounted gyroscope provided by the invention, the front surface of the bottom plate is provided with the annular groove, and the annular groove is arranged around the boss.

According to the heterogeneous integrated surface-mounted gyroscope provided by the invention, the bottom surface of the cover plate is provided with the concave pits, and the concave pits are correspondingly connected with the annular grooves to form the vacuum cavity.

According to the heterogeneous integrated surface-mounted gyroscope provided by the invention, the front surface of the bottom plate is provided with the insulating medium layer, and the insulating medium layer is positioned at the periphery of the annular groove or the boss.

According to the heterogeneous integrated surface-mounted gyroscope provided by the invention, the first bonding layer is arranged above the insulating medium layer, and the second bonding layer used for bonding with the first bonding layer is arranged on the bottom surface of the cover plate.

According to the heterogeneous integrated surface-mounted gyroscope provided by the invention, the bottom plate is a high-resistance silicon bottom plate, and the cover plate is a low-resistance silicon cover plate.

According to the heterogeneous integrated surface-mounted gyroscope provided by the invention, the first bonding layer and the second bonding layer are both made of metal;

or, one of the first bonding layer and the second bonding layer is made of metal, and the other one of the first bonding layer and the second bonding layer is made of silicon;

or the first bonding layer and the second bonding layer are both made of inorganic non-metallic materials.

The invention provides a heterogeneous integrated surface-mounted gyroscope which comprises a bottom plate, an MEMS gyroscope chip and a cover plate. The front of bottom plate is provided with the boss, is provided with the chip electrode on the boss to the back of bottom plate is provided with a plurality of first electrodes, and a plurality of first electrodes all are connected with the chip electrode electricity. The active area of the MEMS gyro chip is welded on the boss, so that the working area of the MEMS gyro chip faces downwards, the MEMS gyro chip is electrically connected with the chip electrode through the bump electrode, a lead is not required to be additionally arranged, and the reduction of the volume of the heterogeneous integrated surface-mounted gyro is facilitated. The cover plate is packaged on the front surface of the bottom plate, a vacuum cavity is reserved between the cover plate and the bottom plate, and the MEMS gyroscope chip is located in the vacuum cavity. In this way, the MEMS gyro chip is hermetically packaged by the bottom plate and the cover plate.

Install the MEME top chip on the boss with the back-off mode directly to be connected through chip electrode and first electrode electricity, make the length of interconnection shorten greatly, be favorable to reducing signal delay, improved the electrical property effectively, and the area of boss is unanimous with the chip size almost, can effectively reduce the volume of this heterogeneous integrated table subsides top. And the MEMS gyroscope chip is packaged by the bottom plate and the cover plate, so that the surface-mounted packaging of the quartz MEMS gyroscope is realized, the miniaturization of the volume can be realized under the condition of not losing the performance of the quartz MEMS gyroscope, and the integration is easier to realize.

Drawings

In order to more clearly illustrate the technical solutions of the present invention or the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a cross-sectional view of a heterogeneous integrated surface mounted gyroscope provided by the present invention;

FIG. 2 is a top view of a base plate provided by the present invention;

FIG. 3 is a bottom view of the base plate provided by the present invention;

fig. 4 is a bottom view of the cover plate provided by the present invention.

Reference numerals:

1: a base plate; 2: a cover plate; 3: a boss; 4: an MEMS gyroscope chip;

5: a vacuum cavity; 6: a ground electrode; 7: a first electrode; 8: a second electrode;

9: a first connection electrode; 10: a first through hole; 11: a second connection electrode;

12: a second through hole; 13: an insulating dielectric layer; 14: a first bonding layer;

15: a second bonding layer; 16: a chip electrode; 17: an annular groove; 18: and (4) pits.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings, and it is obvious that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The heterogeneous integrated surface mounted gyroscope of the present invention is described below with reference to fig. 1-4.

As shown in fig. 1, the heterogeneous integrated surface-mounted gyroscope provided by the present invention includes a bottom plate 1, a MEMS gyroscope chip 4, and a cover plate 2.

The front surface of the bottom plate 1 is provided with a boss 3, the boss 3 is provided with a chip electrode 16, the back surface of the bottom plate 1 is provided with a plurality of first electrodes 7, and the plurality of first electrodes 7 are electrically connected with the chip electrode 16.

The active area of MEMS top chip 4 welds on boss 3, even the workspace of MEMS top chip 4 sets up downwards to MEMS top chip 4 is connected with chip electrode 16 through the bump electrode, like this, makes the workspace of MEMS top chip 4 face bottom plate 1 and be connected with chip electrode 16 electricity, need not additionally to set up the lead wire, is favorable to reducing the volume of this heterogeneous integrated table top-mounted gyroscope. Here, the bump electrodes may be solder bumps arranged in an array provided on the active area of the MEMS gyro chip 4.

Furthermore, the active region of the MEMS gyro chip 4 (i.e., the working region of the MEMS gyro chip 4) realizes the electrical connection between the MEMS gyro chip 4 and the first electrode 7 through the chip electrode 16. Therefore, the MEMS gyro chip 4 is conveniently and electrically connected with an external circuit, so that the heterogeneous integrated surface-mounted gyro can normally work.

The MEME gyro chip is directly installed on the boss 3 in an inverted buckle mode, and is electrically connected with the first electrode 7 through the chip electrode 16, so that the length of interconnection is greatly shortened, the signal delay is favorably reduced, the electrical property is effectively improved, the area of the boss 3 is almost consistent with the size of the chip, and the volume of the heterogeneous integrated surface-mounted gyro can be effectively reduced.

Here, the chip electrode 16 may be a pad of the MEMS gyro chip 4, and the chip electrode 16 is provided with a plurality of terminals for electrical connection with the plurality of first electrodes 7, respectively.

The cover plate 2 is packaged on the front surface of the bottom plate 1, a vacuum cavity 5 is reserved between the cover plate 2 and the bottom plate 1, and the MEMS gyroscope chip 4 is located in the vacuum cavity 5. In this way, MEMS gyro chip 4 is hermetically packaged by base plate 1 and cover plate 2.

It should be noted that, when a chip of a conventional quartz MEMS gyroscope is packaged, a working area of the chip is disposed upward on a substrate, and an I/O end of the chip needs to be connected to each pin on the substrate by a lead, so that the volume of the packaged quartz MEMS gyroscope is increased. The working surface of the MEMS gyroscope chip 4 is connected with the boss in a downward mode, and the MEMS gyroscope chip is electrically connected with the chip electrode through welding of the salient point electrode on the MEMS gyroscope chip and the chip electrode, and a lead does not need to be additionally utilized to be electrically connected with the chip electrode on the bottom plate.

So set up, MEMS top chip 4 welds on boss 3 through the mode of back-off to, bottom plate 1 and apron 2 encapsulate MEMS top chip 4, have realized the surface-mounted encapsulation of quartz MEMS top, can realize the miniaturization of volume under the condition of not losing quartz MEMS top performance, change in the realization that integrates.

In an alternative embodiment of the present invention, the base plate 1 is further provided with a plurality of first connection electrodes 9, and the plurality of first connection electrodes 9 are used to connect the first electrodes 7 and the chip electrodes 16. Here, the first connecting electrode 9 replaces a wire to electrically connect the first electrode 7 and the chip electrode 16. And, the first connection electrode 9 is attached to the front surface of the base plate to reduce the space occupied by the first connection electrode 9.

The bottom plate 1 is further provided with a plurality of first through holes 10, the first through holes 10 are used for the first connecting electrodes 9 to pass through, and the plurality of first through holes 10 are in one-to-one correspondence with the plurality of first connecting electrodes 9, so that the plurality of first connecting electrodes 9 can be conveniently led out. And the part of the first connection electrode 9 located in the first through hole 10 is attached to the hole wall of the first through hole 10, which is beneficial to reducing the volume of the first through hole 10, thereby being beneficial to reducing the volume of the bottom plate 1.

In an alternative embodiment of the present invention, at least two ground electrodes 6 are disposed in the vacuum cavity 5, the ground electrodes 6 surround the bosses 3, that is, the ground electrodes 6 surround the MEMS gyro chip 4, and the back surface of the bottom plate 1 is disposed with a second electrode 8, and the second electrode 8 is electrically connected to the ground electrodes 6. In this way, the second electrode 8 is electrically connected to the ground electrode 6 surrounding the MEMS gyroscope chip 4, which is equivalent to forming a metal cover surrounding the MEMS gyroscope chip 4, thereby playing a role of electrostatic shielding to protect the MEMS gyroscope chip 4 located in the vacuum cavity 5 from the external electric field.

Specifically, two ground electrodes 6 may be disposed in the vacuum cavity 5, and the two ground electrodes 6 are located on two opposite sides of the boss 3, so that the MEMS gyro chip 4 can be located between the two ground electrodes 6.

Of course, a plurality of ground electrodes 6 may also be disposed in the vacuum cavity 5, the ground electrodes 6 may be uniformly distributed outside the boss 3, and the ground electrodes 6 are all electrically connected to the second electrode 8. Thus, the effect of electrostatic shielding is advantageously improved.

In this embodiment, at least two second connection electrodes 11 and at least two second through holes 12 are further disposed on the bottom plate 1, wherein the second connection electrodes 11 are used for connecting the ground electrodes 6 and the second electrodes 8, the second through holes 12 are used for allowing the second connection electrodes 11 to pass through, and the plurality of second through holes 12 correspond to the plurality of second connection electrodes 11 one to one. So configured, the connection of the second electrode 8 and the ground electrode 6 is realized, thereby facilitating the realization of electrostatic shielding.

In an alternative embodiment of the invention, as shown in fig. 2, the front face of the base plate 1 is provided with an annular groove 17, the annular groove 17 being provided around the boss 3.

Here, the top surface of the boss 3 may be flush with the front surface of the base plate 1, and specifically, the boss 3 may be formed by a projection in the middle of the annular groove 17 by the annular groove 17 provided on the front surface of the base plate 1. In this way, the size of the bottom plate 1 is reduced, and the size of the heterogeneous integrated surface-mounted gyroscope is reduced.

In the present embodiment, the ground electrode 6 may be disposed in the annular groove 17 so that the ground electrode 6 surrounds the outer circumference of the boss 3.

And the part of the first connecting electrode 9 in the vacuum cavity 5 is attached in the annular groove 17 to avoid the first connecting electrode 9 from being broken or disconnected from the chip electrode 16 when the heterogeneous integration surface-attached gyroscope vibrates.

In an alternative embodiment, as shown in fig. 4, the bottom surface of the cover plate 2 is provided with a recess 18, the recess 18 is arranged opposite to the annular groove 17, and the recess 18 and the annular groove 17 abut to form the vacuum cavity 5, so that the boss 3 is located in the vacuum cavity 5.

In an alternative embodiment of the present invention, an insulating medium layer 13 is disposed on the front surface of the bottom plate 1, the insulating medium layer 13 may be located at the periphery of the annular groove 17, as shown in fig. 1, the insulating medium layer 13 may also be disposed at the periphery of the boss 3, and the insulating medium layer 13 is configured to isolate the first connecting electrode 9 and the second connecting electrode 11 from the cover plate 2, so as to prevent the first connecting electrode 9 and the second connecting electrode 11 from forming an electrical connection with the cover plate 2, so that the cover plate 2 is electrically connected with the MEMS gyroscope chip 4, and the MEMS gyroscope chip 4 is damaged and cannot work.

Here, the insulating medium layer 13 is fixedly connected to the front surface of the base plate 1, so that the cover plate 2 is fixedly connected to the base plate 1.

In an alternative embodiment of the present invention, a first bonding layer 14 is disposed above the insulating medium layer 13, a second bonding layer 15 is disposed on the bottom surface of the cover plate 2, the second bonding layer 15 is disposed opposite to the first bonding layer 14, and the second bonding layer 15 and the first bonding layer 14 can be bonded, so as to implement the package of the cover plate 2 and the base plate 1.

Here, the shape and size of the first bonding layer 14 and the second bonding layer 15 are identical, and the shape and size of the first bonding layer 14 and the second bonding layer 15 may be adapted to the insulating dielectric layer 13. Thus, the insulating medium layer 13 can prevent the first bonding layer 14 and the second bonding layer 15 from contacting the first connection electrode 9 or the second connection electrode 11 to form an electrical connection while ensuring a large bonding area of the first bonding layer 14 and the second bonding layer 15.

In one mode of this embodiment, both the first bonding layer 14 and the second bonding layer 15 may be made of metal, and the base plate 1 and the cover plate 2 are enabled to realize metal eutectic bonding through bonding of the first bonding layer 14 and the second bonding layer 15, so as to realize packaging of the quartz MEMS gyroscope.

In another mode of this embodiment, one of the first bonding layer 14 and the second bonding layer 15 may be made of metal, and the other may be made of silicon, and the base plate 1 and the cover plate 2 are bonded by the first bonding layer 14 and the second bonding layer 15 to realize gold-silicon bonding.

In another aspect of this embodiment, both the first bonding layer 14 and the second bonding layer 15 may be an inorganic nonmetal, specifically, both the first bonding layer 14 and the second bonding layer 15 may be made of silicon, glass, or silicon and glass. Alternatively, the first bonding layer 14 and the second bonding layer 15 may be adhesive layers, so that the base plate 1 and the cover plate 2 are fixedly packaged by adhesion.

In an alternative embodiment of the present invention, the base plate 1 may be a high resistance silicon base plate and the cover plate 2 may be a low resistance silicon cover plate. Therefore, the bottom plate 1 and the cover plate 2 are both made of silicon materials, so that full silicon packaging is realized, the packaging method is more compatible with a semiconductor process, and automatic production is facilitated.

In this embodiment, the chip electrode, the first electrode, the second electrode, the ground electrode, the first connection electrode, and the second connection electrode may be metal thin film electrodes.

The heterogeneous integrated surface-mounted gyroscope provided by the invention can be manufactured in the following manner.

Firstly, manufacturing a bottom plate 1: the method comprises the following steps of (1) thinning the high-resistance silicon base plate by adopting N-type doped high-resistance silicon as a raw material of the base plate 1 and wet etching to form a wafer with a 'return' -shaped annular groove 17; a certain number of first through holes 10 and second through holes 12 are formed near the annular groove 17 by dry etching; preparing a metal electrode film layer on the surface of a wafer with an annular groove 17, a first through hole 10 and a second through hole 12 by using a sputtering method to form a first connecting electrode 9 and a second connecting electrode 11, transferring an electrode pattern by combining the technologies of photoetching, etching and the like to finish the preparation of a ground electrode 6 in the annular groove 17, finishing the preparation of a chip electrode 16 on a boss 3 in the annular groove 17 and finishing the preparation of a first electrode 7 and a second electrode 8 on the back surface of a high-resistance silicon bottom plate, and realizing the electric connection between the ground electrode 6 in the annular groove 17 and the second electrode 8 on the back surface of the high-resistance silicon bottom plate to form electrostatic shielding; the chip electrode 16 is electrically connected with the first electrode 7; then, preparing an insulating medium layer 13 made of SiO2 on the first connecting electrode 9 and the second connecting electrode 11 by adopting a Chemical Vapor Deposition (CVD) method; preparing a first bonding layer 14 on the insulating medium layer 13 by a sputtering method; secondly, manufacturing a cover plate 2: the method comprises the following steps of (1) thinning the low-resistance silicon cover plate by wet etching by using N-type doped low-resistance silicon as a raw material of the cover plate 2 to form a pit 18 matched with the size, the position and the like of an annular groove 17 of the high-resistance silicon base plate; preparing a second bonding layer 15 around the pit 18 by a sputtering method; and finally, attaching the quartz MEMS gyro chip 4 to the boss 3 in the middle of the annular groove 17 of the high-resistance silicon base plate in an inverted manner, and then carrying out vacuum bonding packaging on the low-resistance silicon cover plate and the high-resistance silicon base plate carrying the MEMS gyro chip 4 in a gold-tin eutectic manner.

In another mode, both the high-resistance silicon bottom plate and the low-resistance silicon cover plate can adopt P-type doped silicon materials as raw materials; the means for thinning the wafer can be dry etching; the first through hole 10 and the second through hole 12 may be formed by laser drilling; the chip electrode 16, the first electrode 7, the second electrode 8, the first connecting electrode 9 and the second connecting electrode 11 can be prepared by electron beam evaporation; the insulating medium layer 13 can adopt Si3N4 material; the high-resistance silicon bottom plate and the low-resistance silicon cover plate can adopt gold bonding, gold silicon bonding and the like.

The above-described embodiments of the apparatus are merely illustrative, and some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment. One of ordinary skill in the art can understand and implement it without inventive effort.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.