A maple leaf-shaped MEMS ring vibrating gyroscope resonator structure

Abstract

The application provides a maple leaf-shaped MEMS ring-shaped vibration gyroscope resonator structure, comprising a substrate, a ring-shaped resonator and an electrode; the ring-shaped resonator and the substrate are bonded, comprising a circular ring-shaped resonant mass with a cavity, a center anchor point arranged at the center of the inner cavity of the circular ring-shaped resonant mass, and a plurality of maple leaf-shaped elastic support beam structures connecting between the center anchor point and the circular ring-shaped resonant mass; the electrode and the substrate are bonded, comprising a driving electrode, a detection electrode, a first control electrode, a second control electrode and a grounding electrode. The application can avoid stress concentration and reduce the influence of residual stress; meanwhile, the support structure is simple and symmetrical, the process is easy to realize, the influence of machining error is small, the process consistency can be ensured, the process tolerance can be effectively improved, the design of the inner arc of the cantilever beam can improve the structural stiffness and improve the impact resistance of the resonator structure, and the design of the inner arc can increase the effective area of the electrode, improve the excitation efficiency and improve the sensitivity of the resonator structure.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of MEMS vibrating gyroscope, and particularly relates to a maple leaf-shaped MEMS ring vibrating gyroscope resonator structure. BACKGROUND

[0002] The MEMS ring gyroscope is an angular velocity sensor based on the Coriolis effect, has the advantages of small volume, integrability, light weight, batch production, low cost, small power consumption, and the like, and is widely applied to the fields of automobile electronics, microsatellites, biomedical science, consumer electronics and the like, and has extremely wide application prospects. The MEMS ring gyroscope belongs to a vibrating gyroscope, the in-plane vibration mode of the ring resonator belongs to a second-order vibration mode, has two working modes: a driving mode and a detection mode, the vibration frequencies of the two modes are the same, and the Coriolis energy is converted between the two working modes. With the development of modern technology, the demand for small-size, low-power, high-precision MEMS ring gyroscopes in various fields is becoming increasingly urgent. However, the existing MEMS ring gyroscopes are limited by processing technology, structural size and other factors, and generally have the problem that a small-size gyroscope has good impact resistance but low sensitivity, and a gyroscope with standard sensitivity has a large size and cannot effectively resist external impact and vibration. Therefore, it is necessary to invent a new resonator structure to solve the problem that the environmental adaptability and high performance of the existing MEMS ring vibrating gyroscope are difficult to be compatible. SUMMARY

[0003] Therefore, it is necessary to provide a maple leaf-shaped MEMS ring vibrating gyroscope resonator structure aiming at the above technical problems.

[0004] A maple leaf-shaped MEMS ring vibrating gyroscope resonator structure comprises:

[0005] a substrate, a ring resonator and an electrode;

[0006] The ring resonator and the substrate are bonded, and comprise: a circular ring-shaped resonant mass with a cavity, a center anchor point arranged at the center of the inner cavity of the circular ring-shaped resonant mass, and a plurality of maple leaf-shaped elastic support beam structures connecting the center anchor point and the circular ring-shaped resonant mass;

[0007] The electrode and the substrate are bonded, and comprise: a driving electrode, a detection electrode, a first control electrode, a second control electrode and a grounding electrode.

[0008] In one embodiment, the maple leaf-shaped elastic support beam structures are rotationally symmetrically distributed around the mass center of the center anchor point, each maple leaf-shaped elastic support beam structure is radially connected to the center anchor point, and the included angle between the axes of any two adjacent maple leaf-shaped elastic support beam structures is 45 degrees.

[0009] In one embodiment, the maple leaf-shaped elastic support beam structure comprises: a first sheet-shaped elastic support cantilever, a second sheet-shaped elastic support cantilever, a first inner arc-shaped elastic support cantilever, a second inner arc-shaped elastic support cantilever, a third sheet-shaped elastic support cantilever, and a fourth sheet-shaped elastic support cantilever.

[0010] The first end of the first sheet-shaped elastic support cantilever and the second sheet-shaped elastic support cantilever is fixedly connected to the outer side of the center anchor point, the radial axis intersects the center of the center anchor point, and the central angle of the first sheet-shaped elastic support cantilever and the second sheet-shaped elastic support cantilever is 45 degrees; the first end of the first inner arc-shaped elastic support cantilever is fixedly connected to the tail end of the first sheet-shaped elastic support cantilever, and the included angle between the first inner arc-shaped elastic support cantilever and the first sheet-shaped elastic support cantilever is 95 degrees; the first end of the second inner arc-shaped elastic support cantilever is fixedly connected to the tail end of the second sheet-shaped elastic support cantilever, and the included angle between the second inner arc-shaped elastic support cantilever and the second sheet-shaped elastic support cantilever is 95 degrees.

[0011] The tail end of the first inner arc-shaped elastic support cantilever is fixedly connected to the first end of the third sheet-shaped elastic support cantilever, and the included angle between the first inner arc-shaped elastic support cantilever and the third sheet-shaped elastic support cantilever is 150 degrees; the tail end of the second inner arc-shaped elastic support cantilever is fixedly connected to the first end of the fourth sheet-shaped elastic support cantilever, and the included angle between the second inner arc-shaped elastic support cantilever and the fourth sheet-shaped elastic support cantilever is 150 degrees; the third sheet-shaped elastic support cantilever and the fourth sheet-shaped elastic support cantilever are fixedly connected to the inner side of the circular ring-shaped resonant mass, and the center line coincides with the axis.

[0012] In one embodiment, the circular ring-shaped resonant mass, the center anchor point, and the maple leaf-shaped elastic support beam structure are formed by silicon wafer processing.

[0013] In one embodiment, the driving electrode and the detection electrode are arranged on the outer side of the circular ring-shaped resonant mass.

[0014] The first control electrode is arranged on the outer side of the first inner arc-shaped elastic support cantilever and the third sheet-shaped elastic support cantilever.

[0015] The second control electrode is arranged on the outer side of the second inner arc-shaped elastic support cantilever and the fourth sheet-shaped elastic support cantilever.

[0016] The grounding electrode is arranged in the cavity surrounded by the first sheet-shaped elastic support cantilever, the second sheet-shaped elastic support cantilever, the first inner arc-shaped elastic support cantilever, and the second inner arc-shaped elastic support cantilever, and is connected to the center anchor point.

[0017] In one of the embodiments, a driving electrode and the detection electrode are arranged outside the annular resonant mass including:

[0018] A first radial separation slit is arranged between the driving electrode and the detection electrode.

[0019] In one of the embodiments, a second radial separation slit is arranged between the maple leaf-shaped elastic support beam structures two by two;

[0020] A third radial separation slit is arranged between the first control electrode and the second control electrode;

[0021] The first control electrode and the second control electrode are mirror-symmetric about the third radial separation slit.

[0022] In one of the embodiments, a first inner arc-shaped separation slit is arranged between the ground electrode and the first control electrode;

[0023] A second inner arc-shaped separation slit is arranged between the ground electrode and the second control electrode;

[0024] A first outer arc-shaped separation slit is arranged between the first control electrode and the second control electrode and the driving electrode and the detection electrode.

[0025] In one of the embodiments, the first radial separation slit and the second radial separation slit are coaxial;

[0026] The third radial separation slit has a width greater than that of the first radial separation slit, and the first radial separation slit has a width greater than that of the second radial separation slit.

[0027] Compared with the prior art, the maple leaf-shaped MEMS ring-shaped vibration gyroscope resonator structure has the following advantages: first, the full-symmetrical inner arc-shaped elastic support cantilever effectively improves the structural stiffness of the ring-shaped gyroscope, so that the impact resistance of the MEMS ring-shaped vibration gyroscope resonator structure is greatly improved, and the inner arc-shaped elastic support cantilever ring-shaped sensitive structure part is designed without sharp right angle, so that stress concentration can be effectively avoided, the influence of residual stress is greatly reduced, and under the same geometric size, the inner arc-shaped design can increase the effective area of the electrode and improve the excitation efficiency; second, the elastic support cantilever connecting the center anchor point and the circular ring-shaped resonant mass part are straight beams, and the included angles between the center lines and the x-axis are 0°, 45°, 90°, 135°, 180°, 225°, 270° and 315°, respectively, which coincide with the vibration main axes of the natural mode, so that the influence of the damping coupling error and the stiffness coupling error on the working mode can be effectively reduced, and the signal-to-noise ratio and the angle sensing accuracy are improved; third, the support structure of the present application is simple and symmetrical, and the process is relatively easy to realize, so that the influence of the machining error is small, the process tolerance can be effectively improved, and the integration of the sensor electromechanical device and the miniaturization of the whole machine can be easily realized; fourth, the present application adopts a fully symmetrical integrated sensitive structure, and the beams are designed with equal interval and close type, so that the process consistency can be ensured, the vibration characteristic parameters (resonant mass, damping coefficient, stiffness coefficient and natural frequency) of the working mode are consistent, the natural mode is naturally matched, and the sensitivity is high. Moreover, since the external interference has the same influence on the driving mode and the sensitive mode, the sensitive structure has strong ability to suppress environmental vibration, external impact and temperature change and other disturbances. Therefore, the present application greatly reduces the drift and orthogonal error caused by process error and environmental temperature change, thereby effectively improving the impact resistance and sensitivity of the MEMS ring-shaped vibration gyroscope resonator structure. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 It is a schematic diagram of a maple leaf-shaped MEMS ring-shaped vibration gyroscope resonator structure in an embodiment;

[0029] Figure 2 It is a schematic diagram of a ring-shaped resonator structure in an embodiment;

[0030] Figure 3 It is a schematic diagram of electrode distribution in an embodiment;

[0031] Figure 4A It is a schematic diagram of the driving mode characteristic frequency result of a maple leaf-shaped MEMS ring-shaped vibration gyroscope resonator structure obtained by finite element simulation software in an embodiment;

[0032] Figure 4BA schematic diagram of a detection modal characteristic frequency result calculated by a finite element simulation software for a maple leaf-shaped MEMS ring-shaped vibration gyroscope resonator structure in an embodiment;

[0033] Figure 5A A schematic diagram of a driving modal characteristic frequency result calculated by a finite element simulation software for an existing ring-shaped resonator structure in an embodiment;

[0034] Figure 5B A schematic diagram of a detection modal characteristic frequency result calculated by a finite element simulation software for an existing ring-shaped resonator structure in an embodiment;

[0035] Figure 6 A schematic diagram of a thermal-elasticity mechanics simulation result calculated by a finite element simulation software for a maple leaf-shaped MEMS ring-shaped vibration gyroscope resonator structure in an embodiment;

[0036] Figure 7 A schematic diagram of a thermal-elasticity mechanics simulation result calculated by a finite element simulation software for an existing ring-shaped resonator structure in an embodiment. DETAILED DESCRIPTION

[0037] Before the specific embodiment of the present application is described, the overall concept of the present application is described as follows:

[0038] The present application is mainly developed for the use of a MEMS ring-shaped gyroscope. The existing MEMS ring-shaped gyroscope is limited by the machining process, structure size and other factors. Generally, a small-sized gyroscope has good impact resistance but low sensitivity, and a gyroscope with standard sensitivity has a large size and cannot effectively resist external impact and vibration.

[0039] The inventor found that the main reason for the above problems is the limitation of the internal structure of the existing MEMS ring-shaped gyroscope. Adjusting the internal structure can avoid the above problems. Therefore, the present application provides a maple leaf-shaped MEMS ring-shaped vibration gyroscope resonator structure, which comprises a substrate, a ring-shaped resonator and an electrode. The ring-shaped resonator and the substrate are bonded, comprising a circular ring-shaped resonant mass with a cavity, a center anchor point arranged at the center of the inner cavity of the circular ring-shaped resonant mass, and a plurality of maple leaf-shaped elastic support beam structures connecting the cylindrical center anchor point and the circular ring-shaped resonant mass. The electrode and the substrate are bonded, comprising a driving electrode, a detection electrode, a first control electrode, a second control electrode and a ground electrode.

[0040] After the overall concept of the present application is introduced, in order to make the purpose, technical scheme and advantages of the present application more clear and explicit, the present application is further described in detail by specific embodiments combined with the drawings.

[0041] It should be noted that, unless otherwise defined, technical or scientific terms used in one or more embodiments of the present disclosure should be understood as having the same meaning as commonly understood by one of ordinary skill in the art to which the present disclosure belongs. The terms "first", "second", and similar terms used in one or more embodiments of the present disclosure do not denote any order, quantity, or importance, but are only used to distinguish different components. The terms "include", "contain", and similar terms mean that the elements or objects before the terms encompass the elements or objects listed after the terms and their equivalents, and do not exclude other elements or objects. The terms "connect" or "connected" or similar terms are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. The terms "upper", "lower", "left", "right", and the like are only used to represent relative positional relationships, and when the absolute positions of the described objects change, the relative positional relationships can also change accordingly.

[0042] For the convenience of understanding, the terms involved in the embodiments of the present application are explained as follows:

[0043] MEMS: Micro-Electro-Mechanical System, also known as micro-electro-mechanical system, micro system, micro machine, etc., refers to a high-tech device with a size of a few millimeters or even smaller.

[0044] Figure 1 A structure diagram of a maple leaf-shaped MEMS ring resonator structure is shown.

[0045] As shown in Figure 1 , it includes a substrate 1, a ring resonator 2, and an electrode 3;

[0046] The ring resonator 2 and the substrate 1 are bonded, as shown in Figure 2 , it includes a circular ring resonant mass 5 with a cavity, a center anchor point 4 arranged at the center of the inner cavity of the circular ring resonant mass 5, and a plurality of maple leaf-shaped elastic support beam structures 6 connecting the center anchor point 4 and the circular ring resonant mass 5;

[0047] The electrode 3 and the substrate 1 are bonded, including a driving electrode 31, a first control electrode 32, a second control electrode 33, a ground electrode 34, and a detection electrode 35. The driving electrode 31 and the detection electrode 35 are circular arc-shaped, and the first control electrode 32 and the second control electrode 33 are arc-shaped.

[0048] Among them, the plurality of maple leaf-shaped elastic support beam structures 6 are rotationally symmetrically distributed around the mass center of the center anchor point 4, each maple leaf-shaped elastic support beam structure 6 is radially connected with the center anchor point 4, and the included angle of the axes of any two adjacent maple leaf-shaped elastic support beam structures 6 is 45 degrees.

[0049] In some embodiments, the center anchor 4 is cylindrical, the number of maple leaf-shaped elastic support beam structures 6 can be eight, and the eight maple leaf-shaped elastic support beam structures 6 are arranged in rotational symmetry around the center of mass of the cylindrical center anchor 4, each maple leaf-shaped elastic support beam structure 6 is connected to the cylindrical center anchor 4 in a radial manner, and the angle between the axes of two adjacent maple leaf-shaped elastic support beam structures 6 is 45 degrees. The eight maple leaf-shaped elastic support beam structures 6 are of the same size, and the height of each of the eight maple leaf-shaped elastic support beam structures 6 is the same as the height of the circular ring-shaped resonant mass 5. The circular ring-shaped resonant mass 5, the center anchor 4, and the maple leaf-shaped elastic support beam structure 6 are all formed by low-resistance silicon wafer processing. The circular ring-shaped resonant mass 5, the cylindrical center anchor 4, and the maple leaf-shaped elastic support beam structure 6 are manufactured integrally by bulk silicon processing technology.

[0050] In some embodiments, the maple leaf-shaped elastic support beam structure 6 includes a first sheet-shaped elastic support beam 61, a second sheet-shaped elastic support beam 62, a first inner arc-shaped elastic support beam 63, a second inner arc-shaped elastic support beam 64, a third sheet-shaped elastic support beam 65, and a fourth sheet-shaped elastic support beam 66.

[0051] The leading ends of the first sheet-shaped elastic support beam 61 and the second sheet-shaped elastic support beam 62 are fixedly connected to the outer side of the center anchor 4, the radial axes intersect at the center of the center anchor 4, and the central angle of the first sheet-shaped elastic support beam 61 and the second sheet-shaped elastic support beam 62 is 45 degrees. The leading end of the first inner arc-shaped elastic support beam 63 is fixedly connected to the trailing end of the first sheet-shaped elastic support beam 61, and the angle between the first inner arc-shaped elastic support beam 63 and the first sheet-shaped elastic support beam 61 is 95 degrees. The leading end of the second inner arc-shaped elastic support beam 64 is fixedly connected to the trailing end of the second sheet-shaped elastic support beam 62, and the angle between the second inner arc-shaped elastic support beam 64 and the second sheet-shaped elastic support beam 62 is 95 degrees.

[0052] The trailing end of the first inner arc-shaped elastic support beam 63 is fixedly connected to the leading end of the third sheet-shaped elastic support beam 65, and the angle between the first inner arc-shaped elastic support beam 63 and the third sheet-shaped elastic support beam 65 is 150 degrees. The trailing end of the second inner arc-shaped elastic support beam 64 is fixedly connected to the leading end of the fourth sheet-shaped elastic support beam 66, and the angle between the second inner arc-shaped elastic support beam 64 and the fourth sheet-shaped elastic support beam 66 is 150 degrees. The third sheet-shaped elastic support beam 65 and the fourth sheet-shaped elastic support beam 66 are fixedly connected to the inner side of the circular ring-shaped resonant mass, and the center line coincides with the axis.

[0053] The inner arc structure of the first inner arc elastic support cantilever 63 and the second inner arc elastic support cantilever 64 can effectively enhance the structural rigidity of the ring-shaped gyroscope, thereby improving the anti-vibration impact capability of the MEMS ring-shaped vibration gyroscope. The obtuse angle design of the inner arc elastic cantilever beam structure can effectively avoid stress concentration and reduce the influence of residual stress. In addition, the area of the first control electrode 32 and the second control electrode 33 can be increased. The inner arc structure improves the structural rigidity without changing the size of the gyroscope structure, but does not increase the thermal elastic damping.

[0054] The drive electrode 31 and the detection electrode 35 are arranged outside the circular ring-shaped resonant mass 5.

[0055] The first control electrode 32 is arranged outside the first inner arc elastic support cantilever 63 and the third sheet-shaped elastic support cantilever 65.

[0056] The second control electrode 33 is arranged outside the second inner arc elastic support cantilever 64 and the fourth sheet-shaped elastic support cantilever 66.

[0057] The ground electrode 34 is arranged in the cavity surrounded by the first sheet-shaped elastic support cantilever 61, the second sheet-shaped elastic support cantilever 62, the first inner arc elastic support cantilever 63, and the second inner arc elastic support cantilever 64, and is connected to the center anchor point 4.

[0058] In some embodiments, eight maple leaf-shaped elastic support beam structures 6 are distributed around the axis of the cylindrical center anchor point 4. Each maple leaf-shaped elastic support beam structure 6 has a first control electrode 32, a second control electrode 33, and a ground electrode 34, and has multiple rectangular radial separation slots, inner arc separation slots, and outer arc separation slots distributed around the axis of the cylindrical center anchor point 4.

[0059] The drive electrode 31 and the detection electrode 35 are arranged outside the circular ring-shaped resonant mass 5.

[0060] A first radial separation slot is arranged between the drive electrode 31 and the detection electrode 35.

[0061] As shown in Figure 3 The eight rectangular first radial separation slots outside the circular ring-shaped resonant mass 5 separate the eight drive electrodes 31 and detection electrodes 35. The length and width of each rectangular first radial separation slot outside the circular ring-shaped resonant mass 5 are consistent, and the size and area of the eight arc-shaped drive electrodes 31 and detection electrodes 35 are completely consistent.

[0062] A second radial separation slot is arranged between every two maple leaf-shaped elastic support beam structures 6.

[0063] A third radial separation slit is arranged between the first control electrode 32 and the second control electrode 33.

[0064] The first control electrode 32 and the second control electrode 33 are mirror-symmetric about the third radial separation slit.

[0065] The axes of the first radial separation slit and the second radial separation slit coincide.

[0066] The width of the third radial separation slit is greater than the width of the first radial separation slit, and the width of the first radial separation slit is greater than the width of the second radial separation slit.

[0067] A first inner arc-shaped separation slit is arranged between the ground electrode 34 and the first control electrode 32.

[0068] A second inner arc-shaped separation slit is arranged between the ground electrode 34 and the second control electrode 33.

[0069] A first outer arc-shaped separation slit is arranged between the first control electrode 32 and the second control electrode 33 and the drive electrode 31 and the detection electrode 35.

[0070] In some embodiments, eight rectangular second radial separation slits inside the circular ring-shaped resonant mass 5 separate different maple leaf-shaped elastic support beam structures 6, the length and width of each rectangular second radial separation slit inside the circular ring-shaped resonant mass 5 are consistent, the size and area of the sixteen first control electrodes 32 and second control electrodes 33 are completely consistent, the size and area of the eight ground electrodes 34 are completely consistent, and the axes of the eight rectangular first radial separation slits outside the circular ring-shaped resonant mass 5 and the eight rectangular second radial separation slits inside the circular ring-shaped resonant mass 5 coincide.

[0071] The width of the rectangular second radial separation slit inside the circular ring-shaped resonant mass 5 is less than the width of the rectangular first radial separation slit outside the circular ring-shaped resonant mass 5; the leading end of the rectangular second radial separation slit inside the circular ring-shaped resonant mass 5 is connected to the cylindrical central anchor point 4, and the trailing end is in communication with the inside of the circular ring-shaped resonant mass 5. The leading end of the rectangular first radial separation slit outside the circular ring-shaped resonant mass 5 is connected to the outside of the circular ring-shaped resonant mass 5, and the trailing end penetrates the outside surface of the arc-shaped electrode layer.

[0072] The first control electrode 32, the second control electrode 33 and the ground electrode 34 of any one maple leaf-shaped elastic support beam structure 6 are provided with a third radial separation slit, a first inner arc-shaped separation slit, a second inner arc-shaped separation slit and a first outer arc-shaped separation slit; the two ends of the third radial separation slit are communicated with the first inner arc-shaped separation slit, the second inner arc-shaped separation slit and the first outer arc-shaped separation slit respectively; the two ends of the first inner arc-shaped separation slit are communicated with the radial rectangular second radial separation slit and the radial rectangular third radial separation slit respectively; the two ends of the second inner arc-shaped separation slit are communicated with the radial rectangular second radial separation slit and the radial rectangular third radial separation slit respectively; the two ends of the outer arc-shaped separation slit are communicated with the adjacent two rectangular second radial separation slits respectively; and the first inner arc-shaped separation slit and the second inner arc-shaped separation slit are communicated. The third radial separation slit, the first inner arc-shaped separation slit, the second inner arc-shaped separation slit and the first outer arc-shaped separation slit jointly separate the first control electrode 32 and the second control electrode 33 which are mirror-symmetrical, and the ground electrode 34 which is connected with the cylindrical center anchor point.

[0073] In operation, the lower end surface of the cylindrical center anchor point 4 is bonded with the base 1 of the MEMS ring vibration gyroscope. The electrode 3 is divided into an inner electrode group (the first control electrode 32 and the second control electrode 33) and an outer electrode group (the driving electrode 31 and the detection electrode 35). The inner side surface of the circular ring-shaped resonant mass 5 is provided with sixteen inner electrode groups with an arc angle of 20 degrees, and adjacent two inner electrode groups are separated by the third sheet-shaped elastic support cantilever 65 and the fourth sheet-shaped elastic support cantilever 66. Eight outer electrode groups with a central angle of 40 degrees are located on the outer side surface of the circular ring-shaped resonant mass 5, and the central axes of adjacent two outer electrode groups are at an angle of 45 degrees. The sixteen inner electrode groups and the eight outer electrode groups are bonded with the silicon base 1 of the MEMS ring vibration gyroscope, and the positions of the eight outer electrode groups correspond to the positions of the eight maple leaf-shaped elastic support beam structures 6 one by one. Moreover, the four driving electrodes 31 and the four detection electrodes 35 are arranged alternately and at intervals.

[0074] Under the same experimental conditions, the stiffness and the thermoelastic damping of the maple leaf-shaped MEMS ring vibration gyroscope resonator structure and the existing ring resonator structure are simulated.

[0075] The equivalent mass and the characteristic frequency of the maple leaf-shaped MEMS ring vibration gyroscope resonator structure are obtained by simulation calculation through the finite element simulation software, and the results are shown in Figs. Figure 4A and Figure 4B According to the formula k = mω 2 , it can be obtained that k = 308 N / m

[0076] The equivalent mass and the characteristic frequency of the existing ring resonator structure are obtained by simulation calculation through the finite element simulation software, and the results are shown in Figs. Figure 5A and Figure 5B According to the formula k = mω2 Thus, k = 206 N / m

[0077] The results are shown in Table 1.

[0078] Name Maple leaf Other Equivalent stiffness k (N / m) 308 206

[0079] Table 1 Comparison table of equivalent stiffness of the structure of the application and equivalent stiffness of the existing structure

[0080] As can be seen from Table 1, under the same experimental conditions, the equivalent stiffness of the maple leaf-shaped MEMS ring vibration gyroscope resonator structure obtained by simulation calculation is greater than the equivalent stiffness of other ring resonator structures obtained by simulation.

[0081] The quality factor Q = 251760 of the maple leaf-shaped MEMS ring vibration gyroscope resonator structure of the application is obtained by thermal-elasticity simulation calculation of the finite element simulation software, and the results are shown in Table 2. Figure 6

[0082] The quality factor Q = 151901 of the existing ring resonator structure is obtained by thermal-elasticity simulation calculation of the finite element simulation software, and the results are shown in Table 2. Figure 7

[0083] The results are shown in Table 2.

[0084] Name Maple leaf Other Quality factor 251760 151901

[0085] Table 2 Comparison table of equivalent stiffness of the structure of the application and quality factor of the existing structure

[0086] The quality factor is an important parameter index in the resonant system. The greater the quality factor Q, the smaller the damping of the resonant system, the higher the resonance peak, the stronger the detected signal, and the better the sensitivity. It also reflects the narrowband filtering performance of the system. In the resonant circuit, the greater the Q value, the better the selectivity. The high-quality factor resonant ring has a more sharp peak in the frequency spectrum at the resonant frequency, so it can select a specific frequency with high fidelity. For many resonant modes, the limit of the quality factor that can be achieved is determined by thermal-elastic damping.

[0087] As can be seen from Table 2, under the same experimental conditions, the Q of the maple leaf-shaped MEMS ring vibration gyroscope resonator structure obtained by simulation calculation is greater than the Q of other ring resonator structures obtained by simulation, i.e. the thermal-elastic damping is small.

[0088] ​​The maple leaf-shaped MEMS ring-shaped vibration gyroscope resonator structure has the following advantages: first, the full-symmetrical inner arc-shaped elastic support cantilever effectively improves the structural stiffness of the ring-shaped gyroscope, so that the impact resistance of the MEMS ring-shaped vibration gyroscope resonator structure is greatly improved, and the inner arc-shaped elastic support cantilever ring-shaped sensitive structure part is designed without sharp right angle, so that stress concentration can be effectively avoided, the influence of residual stress is greatly reduced, and under the same geometric size, the inner arc-shaped design can increase the effective area of the electrode and improve the excitation efficiency; second, the elastic support cantilever connecting the center anchor point and the circular ring-shaped resonant mass part are straight beams, and the included angle between the center line and the x-axis is 0°, 45°, 90°, 135°, 180°, 225°, 270° and 315°, respectively, which coincides with the vibration main axis of the natural mode, so that the influence of the damping coupling error and the stiffness coupling error on the working mode can be effectively reduced, and the signal-to-noise ratio and the angle sensing accuracy are improved; third, the support structure of the present application is simple and naturally symmetrical, and the process is relatively easy to realize, so that the influence of the machining error is small, the process tolerance can be effectively improved, and the integration of the sensor electromechanical device and the miniaturization of the whole machine can be easily realized; fourth, the present application adopts a fully symmetrical integrated sensitive structure, and the beams are designed with equal interval and close type, so that the process consistency can be ensured, the vibration characteristic parameters (resonant mass, damping coefficient, stiffness coefficient and natural frequency) of the working mode are consistent, the natural mode is naturally matched, and the sensitivity is high. Moreover, since the influence of external interference on the driving mode and the sensitive mode is the same, the sensitive structure has strong ability to suppress environmental vibration, external impact and temperature change and other disturbances. Therefore, the drift and orthogonal error caused by process error and environmental temperature change are greatly reduced, so that the impact resistance and the sensitivity of the MEMS ring-shaped vibration gyroscope resonator structure are effectively improved.

[0089] The present application has reasonable structure design and ingenious idea, and can effectively solve the problem that the environmental adaptability and high performance of the existing MEMS ring-shaped vibration gyroscope are difficult to be compatible, and is suitable for the fields of automobile electronics, microsatellite, biomedical, consumer electronics and the like.

[0090] It should be understood by those skilled in the art that the above discussion of any embodiment is only exemplary and is not intended to limit the scope of the present application (including claims) to these examples; under the idea of the present application, the technical features in the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other changes of different aspects of the embodiments of the present application as described above, which are not provided in detail for the sake of brevity.

[0091] Embodiments of the present application are intended to cover all such alternatives, modifications, and variations as fall within the broad scope of the appended claims. Accordingly, any one or more features of any embodiment of the present application can be included in, or prior art to, any one or more features of any other embodiments of the present application; and no characteristics mentioned in this specification should be considered essential (i.e., interpreted in the context of a "means-plus-function" or "step-plus-function" clause) unless the specification expressly states the characteristic is essential.

Claims

1. A maple leaf shaped MEMS ring vibrating gyroscope resonator structure, characterized by, include: The substrate, the ring resonator, and the electrodes; The ring resonator and the substrate are bonded together, including: a ring-shaped resonant mass with a cavity, a central anchor point located at the center of the inner cavity of the ring-shaped resonant mass, and a plurality of maple leaf-shaped elastic support beam structures connecting the central anchor point and the ring-shaped resonant mass. The electrode is bonded to the substrate and includes: a driving electrode, a detection electrode, a first control electrode, a second control electrode, and a ground electrode; The maple leaf-shaped elastic support beam structure includes: a first sheet-shaped elastic support cantilever beam, a second sheet-shaped elastic support cantilever beam, a first inner arc-shaped elastic support cantilever beam, a second inner arc-shaped elastic support cantilever beam, a third sheet-shaped elastic support cantilever beam, and a fourth sheet-shaped elastic support cantilever beam. The first and second sheet-shaped elastic support beams are fixedly connected at their beginning ends to the outer side of the central anchor point, and their radial axes intersect at the center of the central anchor point. The central angle between the first and second sheet-shaped elastic support beams is 45 degrees. The first end of the first inner arc-shaped elastic support beam is fixedly connected to the end of the first sheet-shaped elastic support beam. The angle between the first inner arc-shaped elastic support beam and the first sheet-shaped elastic support beam is 95 degrees. The first end of the second inner arc-shaped elastic support beam is fixedly connected to the end of the second sheet-shaped elastic support beam. The angle between the second inner arc-shaped elastic support beam and the second sheet-shaped elastic support beam is 95 degrees. The tail end of the first inner arc-shaped elastic support beam is fixedly connected to the head end of the third plate-shaped elastic support beam, and the angle between the first inner arc-shaped elastic support beam and the third plate-shaped elastic support beam is 150 degrees; the tail end of the second inner arc-shaped elastic support beam is fixedly connected to the head end of the fourth plate-shaped elastic support beam, and the angle between the second inner arc-shaped elastic support beam and the fourth plate-shaped elastic support beam is 150 degrees; the third plate-shaped elastic support beam and the fourth plate-shaped elastic support beam are fixedly connected to the inner surface of the annular resonant mass, and their center lines coincide with the axis.

2. The maple leaf shaped MEMS ring vibrating gyroscope resonator structure according to claim 1, characterized in that, The maple leaf-shaped elastic support beam structures are distributed symmetrically around the center of mass of the central anchor point. Each maple leaf-shaped elastic support beam structure is radially connected to the central anchor point, and the included angle between the axes of any two adjacent maple leaf-shaped elastic support beam structures is 45 degrees.

3. The maple leaf shaped MEMS ring vibrating gyroscope resonator structure according to claim 1, characterized in that, The annular resonant mass, the central anchor point, and the maple leaf-shaped elastic support beam structure are formed from silicon wafers.

4. The maple leaf shaped MEMS ring vibrating gyroscope resonator structure according to claim 1, characterized in that, The driving electrode and the detection electrode are spaced apart and disposed outside the annular resonant mass; The first control electrode is disposed on the outside of the first inner arc-shaped elastic support beam and the third sheet-like elastic support beam; The second control electrode is disposed on the outside of the second inner arc-shaped elastic support beam and the fourth sheet-like elastic support beam; The grounding electrode is disposed within the cavity formed by the first sheet-like elastic support beam, the second sheet-like elastic support beam, the first inner arc-shaped elastic support beam, and the second inner arc-shaped elastic support beam, and is connected to the central anchor point.

5. The maple leaf shaped MEMS ring vibrating gyroscope resonator structure according to claim 4, characterized in that, The driving electrode and the detection electrode are spaced apart and disposed outside the annular resonant mass, including: A first radial separation slit is provided between the driving electrode and the detection electrode.

6. The maple leaf shaped MEMS ring vibrating gyroscope resonator structure according to claim 5, characterized in that, The maple leaf-shaped elastic support beam structure is provided with a second radial separation joint between each pair of beams. A third radial partition slit is provided between the first control electrode and the second control electrode; The first control electrode and the second control electrode are mirror-symmetrical about the third radial dividing slit.

7. The maple leaf shaped MEMS ring vibrating gyroscope resonator structure according to claim 4, characterized in that, A first inner arc-shaped partition slit is provided between the grounding electrode and the first control electrode; A second inner arc-shaped partition is provided between the grounding electrode and the second control electrode; A first outer arc-shaped partition is provided between the first control electrode and the second control electrode and the driving electrode and the detection electrode.

8. The maple leaf shaped MEMS ring vibrating gyroscope resonator structure according to claim 6, characterized in that, The axes of the first radial dividing seam and the second radial dividing seam coincide; The width of the third radial dividing joint is greater than the width of the first radial dividing joint, and the width of the first radial dividing joint is greater than the width of the second radial dividing joint.

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