Membrane device with electromagnetic shielding function and method for manufacturing the same

Abstract

The application provides a MEMS device with electromagnetic shielding function and a manufacturing method thereof. A movable flexible component is arranged on a device layer, the support substrate is coupled to a cover wafer through the movable flexible component, the floating potential of the support substrate is released, the electromagnetic interference of the substrate potential floating on the device layer is inhibited, and the stability of the micro-electro-mechanical system in a complex electromagnetic environment is improved. The manufacturing method comprises the following steps: aligning and bonding one side of the cover wafer with a patterned metal layer to the device layer to define a gas-tight cavity between the cover wafer and the MEMS device, and coupling the support substrate to the cover wafer through the movable flexible component to release the floating potential of the substrate, which is easy to implement.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of microelectronic devices, and particularly relates to a MEMS device and a manufacturing method thereof. BACKGROUND

[0002] With the continuous development of micro-nano processing technology and integrated circuit technology, the manufacturing process of MEMS devices is becoming more and more advanced, and the performance is becoming more and more excellent. MEMS devices have great potential in the fields of medical treatment, environmental monitoring, energy management, etc. For example, MEMS sensors can be used for monitoring and tracking of medical devices, MEMS oscillators can be used for clock synchronization in wireless communication, and MEMS energy collectors can be used for power supply of low-power devices.

[0003] Generally, when designing and manufacturing electronic devices, electromagnetic shielding measures are needed to improve the anti-interference ability of the device in consideration of possible external electromagnetic interference, so that the device can operate stably in a complex electromagnetic environment. At present, the commonly used wafer type for micro-fabrication process of MEMS is SOI wafer. The process flow of manufacturing MEMS devices using SOI wafer includes: etching a device layer including MEMS structure on the top layer of silicon, then releasing the intermediate buried oxide layer by means such as vapor phase hydrogen fluoride (VHF), thereby obtaining a movable structure of MEMS, and finally realizing electrical connection of the device layer by using bonding technology and through-silicon via (TSV) technology; but in this case the back substrate of the SOI wafer is floating. At present, conductive adhesive or a metal layer is applied at the bottom of the back substrate of the SOI wafer, and then the SOI substrate is electrically led out by means of gold wire bonding. The above-mentioned means all have the problems of high difficulty and cost in process implementation, and certain limitations exist.

[0004] It should be noted that the above introduction to the technical background is only for the convenience of clearly and completely describing the technical scheme of the present application, and for the convenience of understanding by those skilled in the art. The above technical scheme cannot be considered as known to those skilled in the art only because it is described in the background section of the present application. SUMMARY

[0005] In view of the above-mentioned shortcomings of the prior art, the purpose of the present application is to provide a MEMS device with electromagnetic shielding function and a manufacturing method thereof, which is used to solve the problem that the substrate of the existing MEMS device has floating potential, thereby affecting the stability and reliability of the micro-electro-mechanical system.

[0006] To achieve the above-mentioned purpose and other related purposes, the present application provides a MEMS device with electromagnetic shielding function, comprising:

[0007] a support substrate;

[0008] a device layer on the support substrate, the device layer including a resonant MEMS device housed in a cavity through the device layer, and a movable flexible member having one end fixed to a body of the device layer and suspended over the support substrate, the movable flexible member including a contact unit flexibly connected to the body of the device layer in a state of being suspended over the support substrate, the contact unit including a first flexible member and a bump connected between the first flexible member and the body of the device layer;

[0009] a cap wafer including a shield layer on a surface thereof, one side of the cap wafer being aligned and bonded with the device layer to hermetically seal the MEMS device in the cavity, thereby maintaining a vacuum environment, and to cause a free end of the contact unit to move downward to contact the support substrate in a state of the bump abutting against the shield layer at an anchor point position, the support substrate being electrically insulated from the body of the device layer and being externally coupled with the cap wafer through the movable flexible member for releasing a floating potential of the support substrate.

[0010] Optionally, the movable flexible member is integrally formed with the body of the device layer, the movable flexible member including a second flexible member configured to flexibly connect the contact unit to the body of the device layer.

[0011] Optionally, the bump includes an intermediate connecting block and a contact portion protruding from the intermediate connecting block toward the cap wafer, the intermediate connecting block being flexibly connected to the body of the device layer through the second flexible member to provide soft contact of the contact portion to the anchor point.

[0012] Optionally, one side of the cap wafer with the shield layer is aligned and bonded with the device layer to form a bonding layer between the shield layer and the device layer, the bonding layer including a first bonding region formed at an interface between the device layer peripheral to the resonant MEMS device and the shield layer.

[0013] Optionally, the bonding layer further includes a second bonding region formed at an interface between the device layer peripheral to the movable flexible member and the shield layer; and a sum of heights of the contact portion and the anchor point is greater than a sum of heights of the shield layer and the second bonding region in a state of the contact portion being in contact with the anchor point, so that a free end of the movable flexible member at least point contacts the support substrate in a state of the contact portion abutting against the cap wafer.

[0014] Optionally, the contact unit further comprises a movable mass provided at a free end thereof, the movable mass being flexibly connected to the intermediate connecting block by the first flexible member, wherein the first flexible member is configured as a resilient beam structure.

[0015] The application also provides a method for manufacturing a MEMS device with electromagnetic shielding function, comprising the following steps:

[0016] A support substrate is provided, and an insulating layer and a semiconductor layer are sequentially formed on the support substrate;

[0017] The upper layer of the semiconductor layer is patterned to form a protruding portion;

[0018] The semiconductor layer is patterned for the second time along the thickness direction until the insulating layer is exposed, and a device layer including a movable flexible component and a resonant MEMS device region is formed in the semiconductor layer, the movable flexible component is configured to be connected to the body of the device layer at one end, and the movable flexible component includes a contact unit, the contact unit includes a first flexible member and a bump connected between the first flexible member and the body of the device layer;

[0019] The insulating layer under the resonant MEMS device and the movable flexible component is removed to release the resonant unit of the resonant MEMS device and the movable flexible component, and the contact unit is flexibly connected to the body of the device layer in a state that the movable flexible component is suspended at the free end thereof above the support substrate;

[0020] A cover wafer is provided, a metal layer is formed on the cover wafer, and the metal layer is patterned, and the patterned metal layer is formed as a shielding layer;

[0021] One side of the cover wafer with the shielding layer is aligned and bonded to the semiconductor layer to hermetically seal the resonant MEMS sensor in a cavity penetrating through the device layer, so as to maintain a vacuum environment, and the bump is caused to abut against the shielding layer at an anchor point position, so that the free end of the contact unit is moved downward to contact the support substrate, for releasing the floating potential of the support substrate.

[0022] Optionally, the insulating layer is etched by anisotropic etching of gaseous hydrogen fluoride to release the resonant unit of the resonant MEMS device and the movable flexible component.

[0023] Optionally, one side of the cover wafer with the shielding layer is aligned and bonded to the semiconductor layer to form a bonding layer at least at the interface between the device layer of the resonant MEMS device periphery and the shielding layer, and the bonding layer includes one of a metal solder bonding layer and a eutectic bonding layer.

[0024] Optionally, the insulating layer is an insulating bonding layer formed between the support substrate and the semiconductor layer by an anodic bonding process, wherein the material of the semiconductor layer comprises one or more selected from the group consisting of the IV main group.

[0025] As described above, the present application provides a MEMS device with electromagnetic shielding function and a manufacturing method thereof. By providing a movable flexible component on the device layer, the support substrate is coupled to the cover wafer through the movable flexible component to release the floating potential of the support substrate, thereby suppressing the electromagnetic interference of the device layer caused by the floating potential of the substrate, improving the stability and reliability of the device, and improving the stability and reliability of the device. The ability of the micro-electro-mechanical system to operate stably in a complex electromagnetic environment; in addition, the manufacturing method comprises aligning and bonding the side of the cover wafer with the patterned metal layer to the device layer, defining a gas-tight cavity between the cover wafer and the MEMS device, and simultaneously coupling the support substrate to the cover wafer through the movable flexible component to release the floating potential of the substrate. Easy to implement, and has wide application prospect. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 A cross-sectional view of the MEMS device with electromagnetic shielding function of the present application is shown.

[0027] Figure 2 A cross-sectional view of the movable flexible component is shown. Figure 1 A top view of the movable flexible component is shown.

[0028] Figure 3 A cross-sectional view of the movable flexible component is shown. Figure 2 A top view of the movable flexible component is shown.

[0029] Figures 4 to 10 A cross-sectional view of the MEMS device with electromagnetic shielding function of the present application is shown.

[0030] Element number explanation:

[0031] 10 support substrate

[0032] 20 device layer

[0033] 30 cover wafer

[0034] 201 cavity

[0035] 21 resonant MEMS device

[0036] 22 movable flexible component

[0037] 220 contact unit

[0038] 230 second flexible member

[0039] 223 intermediate connecting block

[0040] 2231 contact portion

[0041] 224 first flexible member

[0042] 225 movable mass

[0043] 110 insulating layer

[0044] 200 semiconductor layer

[0045] 301 opening

[0046] 31 shielding layer

[0047] 311 anchor point DETAILED DESCRIPTION

[0048] The present application is herein described, by way of example only, with the application can be implemented or applied in other different embodiments, and the details thereof can be varied as desired, without departing from the spirit of the application.

[0049] Reference will now be made to the drawings, wherein Figures 1 to 10 It is to be understood that the drawings are to be used only for illustrative purposes and that the present application can be practiced in a variety of embodiments with additional components, different components, different shapes, different sizes, and / or different arrangements of the components, and that the scope of the present application is not limited to the details of construction and the arrangement of the components shown in the drawings.

[0050] Example 1

[0051] As Figures 1 to 3As shown, the embodiment provides a MEMS device with electromagnetic shielding function, comprising a support substrate 10, a device layer 20 and a cover wafer 30, the device layer 20 is located on the support substrate 10, the device layer 20 comprises a resonant MEMS device 21 and a movable flexible component 22, the resonant MEMS device 21 is contained in a cavity 201 through the device layer, the movable flexible component 22 is suspended above the support substrate 10 with one end fixed to the body of the device layer, the movable flexible component 22 comprises a contact unit 220 flexibly connected to the body of the device layer in a state of being suspended above the support substrate 10, the contact unit 220 comprises a first flexible member 224 and a bump connected between the first flexible member 224 and the body of the device layer 20; the cover wafer 30 comprises a shielding layer 31 formed on its surface, one side of the cover wafer 30 with the shielding layer 31 is aligned and bonded with the device layer 20 to seal the resonant MEMS device in the cavity in airtight manner, thereby maintaining a vacuum environment, and the bump is caused to abut against the shielding layer 31 at an anchor point 311 position, so that the free end of the contact unit 220 away from the body of the device layer moves downward to contact the support substrate 10, the support substrate 10 is electrically insulated from the body of the device layer and is coupled to the cover wafer 30 through the movable flexible component 22 out of plane, for releasing the floating potential of the support substrate. Since the resonant MEMS device is sealed in the cavity in airtight manner to maintain a vacuum environment, the air damping loss of the resonator can be effectively reduced, thereby improving the quality factor (Q) value of the resonator.

[0052] Specifically, the movable flexible component 22 is integrally formed with the body of the device layer, the movable flexible component 22 comprises a second flexible member 230, the second flexible member 230 is configured to flexibly connect the contact unit 220 to the body of the device layer in a state of being suspended above the support substrate 10, the second flexible member 230 is joined to the body of the device layer for providing flexible force for the up and down deflection of the contact unit 220, during the packaging process, the movable flexible component 22 is arranged in a state that the bump abuts against the corresponding anchor point, to provide support force for the contact unit 220, while providing flexible force for the bump to abut against the cover wafer.

[0053] Referring to Figure 3 which shows Figure 2The second flexible member 230 is configured as a resilient beam structure, such as a folding beam, a spring structure of S-shaped flexible beams connected in sequence, which allows the bump to swing or rotate relative to the device layer body, further reduces the rigidity of the mechanical connection, and improves the manufacturability of the process; or the second flexible member is selected, such as a bending beam, a straight beam or the like.

[0054] As shown in Figure 2 , the bump includes an intermediate connecting block 223, and a contact portion 2231, such as a contact, provided on the intermediate connecting block 223 and protruding towards the cover wafer 30, wherein the intermediate connecting block 223 is connected between the first flexible member 224 and the second flexible member 230.

[0055] In some embodiments, the intermediate connecting block 223 is formed of the same or different material as the contact portion.

[0056] Continuing to refer to Figure 2 , the anchor point 311 is provided in a movable connection with the contact portion 2231, wherein the contact portion 2231 forms at least a point contact with the anchor point 311, and the stress provided by the second flexible member 230 against the anchor point 311 realizes the soft contact of the contact portion 2231 to the anchor point 311, reduces the rigidity of the contact, and further improves the stability and reliability of the device, wherein the shielding layer is selected as a metal shielding layer, and the material thereof includes but is not limited to Al, Ge, Ti, Pt, Au, In, Sn, Cu or the like.

[0057] Referring to Figure 2 , the device layer 20 and the cover wafer 30 are fixedly connected, for example, one side of the cover wafer with the shielding layer is aligned and bonded with the device layer 20 to form a bonding layer between the shielding layer and the device layer, and the bonding layer includes a first bonding area formed at the interface between the shielding layer and the device layer in the periphery of the resonant MEMS device to hermetically seal the resonant MEMS device in the cavity 201, thereby maintaining a vacuum environment.

[0058] In some embodiments, the shielding layer is selected as a metal shielding layer, and the bonding layer can be formed by corresponding bonding of the metal shielding layer and a metal solder provided on the device layer, wherein the material of the metal solder can be set according to the design of the metal bonding reaction, and various disclosed metal bonding materials can be used. In other embodiments, the bonding layer is selected as a eutectic bonding layer to realize low-temperature vacuum hermetic bonding between the device layer and the cover wafer.

[0059] Further, the bonding layer further comprises a second bonding region formed at the interface between the device layer 20 of the movable flexible component periphery and the shielding layer 31, so as to fixedly connect the device layer body around the movable flexible component to the cover wafer 30, and increase the stability when the free end of the movable flexible component is deflected; in the state that the contact portion 2231 is in contact with the anchor point 311, the sum of the height of the contact portion 2231 and the anchor point 311 is greater than the sum of the height of the shielding layer 31 and the second bonding region, so that when the contact portion 2231 is abutted to the cover wafer 30, the end of the contact unit away from the device layer body is driven to move downward by the first flexible member 224, so that the free end of the contact unit is at least point-contacted on the support substrate 10.

[0060] As shown in Figure 3 , the contact unit 220 comprises at least one first flexible member 224, which is configured to have the same structure as the second flexible member, for example, configured as a folded beam. It should be noted that the implementation mode of the assembly or element is described by taking the number of the first flexible member shown in the figure as an example, but the structure and number of the present application are not limited thereto.

[0061] As shown in Figure 2 and Figure 3 , the contact unit 220 comprises a movable mass 225 arranged at the free end thereof, which is located at the end of the contact unit 220 away from the device layer body. Since the movable mass 225 and the intermediate connecting block 223 are flexibly connected by the first flexible member 224, in the state that the contact portion 2231 is abutted to the anchor point 311, the intermediate connecting block 223 causes the first flexible member 224 to deflect, thereby driving the movable mass 225 away from the device layer body to move downward to contact the support substrate 10.

[0062] In some embodiments, an insulating bonding layer is formed between the device layer 20 and the support substrate 10, so as to electrically insulate the support substrate 10 from the body of the device layer 20, and the support substrate 10 is coupled to the cover wafer 30 through the movable flexible component 22 out of the plane, the floating potential of the support substrate is released, thereby improving the anti-interference ability of the MEMS device, so that the device has better stability and reliability in a complex electromagnetic environment. Since the movable flexible component is configured to be bonded to the body of the device layer, it is at the same potential as the body of the device layer. Preferably, the device layer 20 and the support substrate 10 are hermetically bonded to form an insulating bonding layer at the interface therebetween, and the insulating bonding layer comprises silicon dioxide.

[0063] The device layer comprises a resonant MEMS device selected from one of a MEMS resonator, a temperature sensor, a pressure sensor, and an inertial sensor, wherein the inertial sensor comprises one of a MEMS accelerometer and a MEMS gyroscope.

[0064] Embodiment II

[0065] The application further provides a method for manufacturing a MEMS device with electromagnetic shielding function, comprising the following steps:

[0066] Firstly, step S1 is performed: a support substrate 10 is provided, and an insulating layer 110 and a semiconductor layer 200 are sequentially formed on the support substrate 10.

[0067] Specifically, the support substrate 10 can be a single material layer or a laminated structure composed of at least two layers of different materials, such as silicon (Si), silicon oxide (SiO2), or a laminated structure of SiO2 / Si, etc.; the material of the semiconductor layer 200 can be selected from one or more of the group IV elements in the periodic table, such as silicon, germanium, carbon, silicon germanium, or silicon carbide, and the semiconductor layer 200 can contain dopants, such as phosphorus, arsenic, antimony, boron, or aluminum.

[0068] Step S1 includes: the doping process of the semiconductor layer can be performed by an in-situ doping process when the semiconductor layer is grown, or performed after the step of growing the semiconductor layer and before the step of patterning.

[0069] It should be noted that the resonant MEMS device can be manufactured by known materials using known techniques, which include but are not limited to binary compounds or multi-component compounds composed of at least two elements selected from the group III, IV, V, and VI, such as gallium phosphide, aluminum gallium phosphide, silicon nitride, silicon oxide, aluminum carbide, aluminum nitride, and / or aluminum oxide, etc.

[0070] In this embodiment, referring to Figure 4 , the resonant MEMS device is manufactured using a semiconductor-on-insulator substrate comprising a buried oxide layer and a top semiconductor layer, and the top semiconductor layer is formed into a device layer in subsequent processes, for example, the top semiconductor layer is selected as a top silicon layer. Alternatively, the insulating layer is selected as an insulating bonding layer formed between the support substrate 10 and the semiconductor layer 200 by an anodic bonding process, for example, the support substrate 10 is selected as a silicon-based substrate, the semiconductor layer 200 contains silicon, and the insulating bonding layer is formed as an oxygen-silicon chemical covalent bonding layer.

[0071] Then, step S2 is performed: the upper surface layer of the semiconductor layer is patterned to form a contact portion 2231.

[0072] Specifically, referring toFigure 5 A mask layer is formed on the surface of the semiconductor layer by, for example, a plasma enhanced chemical vapor deposition process; subsequently, the surface of the semiconductor layer and the contact portion 2231 protruding from the surface of the semiconductor layer are exposed again by a photolithography, etching or other process, wherein the process of etching the semiconductor layer can be a dry etching process.

[0073] In some embodiments, the contact portion 2231 is formed as a contact protruding from the exposed surface of the semiconductor layer.

[0074] Then, step S3 is performed to pattern the semiconductor layer 200 in the thickness direction for the second time until the insulating layer 110 is exposed, thereby forming a device layer including a movable flexible member and a resonant MEMS device region in the semiconductor layer 200, the movable flexible member 22 being configured to have one end jointed to the body of the device layer, the movable flexible member 22 including a contact unit 220, the contact unit 220 including a first flexible member 224 and a bump connected between the first flexible member 224 and the body of the device layer 20.

[0075] Specifically, referring to Figure 6 Step S3 includes etching the semiconductor layer 200 in the thickness direction by a deep reactive ion etching (DRIE) process based on a photolithography mask to define a resonant unit of a MEMS device, a driving electrode and a detection electrode, and a movable flexible member 22 in the semiconductor layer, the movable flexible member 22 including a contact unit 220 jointed to the body of the device layer, the contact unit 220 including a first flexible member 224 and a bump connected between the first flexible member 224 and the body of the device layer 20.

[0076] Then, referring to Figure 7 Step S4 is performed to remove the insulating layer under the resonant MEMS device and the movable flexible member to release the movable flexible member 22 and the resonant unit of the resonant MEMS device, the movable flexible member 22 being flexibly connected to the body of the device layer 20 with the free end of the movable flexible member 22 suspended over the support substrate.

[0077] Referring to Figure 7 The insulating layer is selected to be a sacrificial material, for example, an oxide containing silicon or germanium, and the insulating layer 110 is etched by a vapor phase hydrogen fluoride (VHF) anisotropic etching process to release the movable flexible member 22 and at least the resonant unit. Since the etching process using hydrogen fluoride is selective, the insulating layer can be removed without affecting the characteristics of the resonant structure and the support substrate.

[0078] Then, referring to Figure 8After step S4, step S5 is performed to provide a cover wafer 30, form a metal layer on the cover wafer 30, and pattern the metal layer to form a shielding layer 31.

[0079] In particular, the material of the cover wafer 30 can be one of silicon or glass, as shown in Figure 7 Step S5 includes forming a metal layer on the cover wafer 30 by using a process such as physical vapor deposition, magnetron sputtering, electron beam evaporation, or electroplating, and patterning the metal layer by photolithography and wet etching, wherein the material of the metal layer includes but is not limited to one or a combination of Al, Ge, Ti, Pt, Au, In, Sn, Cu.

[0080] Then, step S6 is performed to align and bond the side of the cover wafer 30 with the shielding layer to the device layer 20 to hermetically seal the resonant MEMS device in the cavity 201, thereby maintaining a vacuum environment, and to cause the contact unit to move downward to contact the support substrate 10 for releasing the levitation potential of the support substrate in a state that the bump is against the shielding layer at an anchor point 311 position.

[0081] As shown in Figure 8 Before performing the bonding step, the method further includes etching the cover wafer 30 to form an opening 301 corresponding to the movable flexible component 22 and the resonant MEMS device on the side of the cover wafer 30 with the shielding layer.

[0082] As shown in Figures 9 to 10 The side of the cover wafer 30 with the shielding layer is aligned and bonded to the device layer 20 to form a bonding layer between the shielding layer 31 and the device layer 20, wherein the bonding layer includes one of a metal solder bonding layer and a eutectic bonding layer.

[0083] In some embodiments, a low-temperature bonding process is used to hermetically bond the shielding layer 31 to the device layer surrounding the resonant MEMS device to form a first bonding region at the interface between the device layer surrounding the resonant MEMS device and the shielding layer, thereby providing a moving space for the sensitive device in a vacuum environment, and the bonding layer for hermetic bonding includes a metal solder bonding layer such as Pt-Au or Al-Pt, or a eutectic bonding layer such as an Al-Ge eutectic bonding layer, an Al-Si eutectic bonding layer, or an Au-Si eutectic bonding layer. Preferably, the bonding layer further includes a second bonding region formed at the interface between the device layer surrounding the movable flexible component and the shielding layer 31 to increase the stability when the free end of the movable flexible component is deflected.

[0084] In some embodiments, before or after the step S6 of aligning and bonding the cover wafer 30 with the shielding layer on one side with the device layer 20, the preparation method further comprises: forming a vertical feedthrough in the cover wafer 30 to connect the electrode lead-out end of the MEMS device or die to an external electrical signal.

[0085] In summary, the present application provides a MEMS device with electromagnetic shielding function. By providing a movable flexible component in the device layer, the support substrate is coupled to the cover wafer through the movable flexible component to release the floating potential of the support substrate, thereby suppressing the electromagnetic interference of the substrate potential floating on the operation of the device layer, improving the stability and reliability of the device in a complex electromagnetic environment. Therefore, the present application effectively overcomes the shortcomings of the prior art and has high industrial utilization value.

[0086] The above embodiments only exemplarily illustrate the principles and effects of the present application, and are not intended to limit the present application. Any person skilled in the art can modify or change the above embodiments without departing from the spirit and scope of the present application. Therefore, all equivalent modifications or changes made by those skilled in the art without departing from the spirit and technical concept disclosed by the present application should be covered by the claims of the present application.

[0087] In addition, in the description of the present application, the terms "first", "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined with "first", "second" can explicitly or implicitly include one or more features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise specifically limited.

Claims

1. A MEMS device having an electromagnetic shielding function, characterized by, The application relates to a resonant MEMS device, comprising: a support substrate; a device layer on the support substrate, the device layer comprising a resonant MEMS device and a movable flexible component, the resonant MEMS device being accommodated in a cavity through the device layer, the movable flexible component being suspended over the support substrate with one end of the movable flexible component being fixed to a body of the device layer, the movable flexible component comprising a contact unit flexibly connected to the body of the device layer in a state of being suspended over the support substrate, the contact unit comprising a first flexible member and a bump connected between the first flexible member and the body of the device layer; a cover wafer comprising a shielding layer on a surface of the cover wafer, one side of the cover wafer with the shielding layer being aligned and bonded to the device layer to hermetically seal the MEMS device in the cavity, thereby maintaining a vacuum environment, and to cause a free end of the contact unit to move downward to contact the support substrate in a state of the bump abutting against the shielding layer at an anchor point position, the support substrate being electrically insulated from the body of the device layer and being coupled to the cover wafer through the movable flexible component for releasing a floating potential of the support substrate.

2. The MEMS device of claim 1, wherein: The movable flexible component is integrally formed with the body of the device layer, and the movable flexible component comprises a second flexible member configured as a resilient beam structure to flexibly connect the contact unit to the body of the device layer.

3. The MEMS device of claim 2, wherein: The bump comprises an intermediate connecting block and a contact portion protruding from the intermediate connecting block and towards the cover wafer, the intermediate connecting block being flexibly connected to the body of the device layer through the second flexible member to provide soft contact of the contact portion to the anchor point.

4. The MEMS device of claim 1, wherein: One side of the cover wafer with the shielding layer is aligned and bonded to the device layer to form a bonding layer between the shielding layer and the device layer, the bonding layer comprising a first bonding region formed at an interface between the device layer in a periphery of the resonant MEMS device and the shielding layer.

5. The MEMS device of claim 4, wherein: The bonding layer further comprises a second bonding region formed at an interface between the device layer in a periphery of the movable flexible component and the shielding layer; the bump comprises an intermediate connecting block and a contact portion protruding from the intermediate connecting block and towards the cover wafer, a sum of heights of the contact portion and the anchor point in a state of the contact portion being in contact with the anchor point being greater than a sum of heights of the shielding layer and the second bonding region, so that a free end of the movable flexible component at least point contacts the support substrate in a state of the contact portion abutting against the cover wafer.

6. The MEMS device of claim 3, wherein: The contact unit further comprises a movable mass arranged at the free end of the contact unit, the movable mass being flexibly connected to the intermediate connecting block through the first flexible member, wherein the first flexible member is configured as a resilient beam structure.

7. A method of manufacturing a MEMS device having an electromagnetic shielding function, characterized by, The manufacturing method comprises the following steps: providing a support substrate, the support substrate sequentially having an insulating layer and a semiconductor layer formed thereon; patterning an upper layer of the semiconductor layer to form a protruding portion; secondly patterning the semiconductor layer in the thickness direction until the insulating layer is exposed, forming a device layer including a movable flexible component and a resonant MEMS device region in the semiconductor layer, the movable flexible component is configured to have one end jointed to the body of the device layer, the movable flexible component includes a contact unit, the contact unit includes a first flexible member and a bump connected between the first flexible member and the body of the device layer; removing the insulating layer under the resonant MEMS device and the movable flexible component to release the resonant unit of the resonant MEMS device and the movable flexible component, the contact unit is flexibly connected to the body of the device layer with the free end of the movable flexible component hanging in the state of the support substrate; providing a cover wafer, forming a metal layer on the cover wafer and patterning the metal layer, the patterned metal layer is formed as a shielding layer; aligning and bonding the side of the cover wafer with the shielding layer to the semiconductor layer to hermetically seal the resonant MEMS sensor in the cavity penetrating through the device layer, thereby maintaining a vacuum environment, and causing the free end of the contact unit to move downward to contact the support substrate in the state of the bump abutting against the shielding layer at an anchor point position, for releasing the floating potential of the support substrate.

8. The method of manufacturing according to claim 7, wherein: anisotropic etching the insulating layer by using gaseous hydrogen fluoride to release the movable flexible component and the resonant unit of the resonant MEMS device.

9. The method of making of claim 7, wherein: aligning and bonding the side of the cover wafer with the shielding layer to the semiconductor layer to form a bonding layer at least at the interface between the device layer of the resonant MEMS device periphery and the shielding layer, the bonding layer includes one of a metal solder bonding layer and a eutectic bonding layer.

10. The method of making of claim 7, wherein: the insulating layer is selected to be an insulating bonding layer formed between the support substrate and the semiconductor layer by an anodic bonding process, wherein the material of the semiconductor layer includes one or more selected from the combination of the IV main group. the insulating layer is selected to be an insulating bonding layer formed between the support substrate and the semiconductor layer by an anodic bonding process, wherein the material of the semiconductor layer includes one or more selected from the combination of the IV main group.

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