A four-mass mechanical amplification type MEMS gyroscope

Abstract

The application provides a MEMS gyroscope, which comprises a substrate, a device layer, a driving structure, a driving electrode structure, a detection structure, a detection beam and a detection electrode unit, wherein the device layer is fixed on the substrate and comprises a plurality of structure units which are connected to each other and arranged in an array; the driving structure is located in the structure unit and comprises a mass, a driving frame, an elastic beam, a first folded beam, a first combined beam, a second combined beam and a third combined beam; the driving electrode structure is located in the structure unit and comprises a first capacitor, a second capacitor and a third capacitor; the detection structure is located in the structure unit and comprises a detection frame and a movable electrode frame; the detection beam is located in the structure unit and connected with the movable electrode frame, and the cross end point of the detection beam is connected with the mass; a plurality of detection electrode units are located in the internal region of the detection frame, and the detection electrode units comprise a fourth capacitor, a fifth capacitor, a sixth capacitor and a seventh capacitor arranged in an array. The MEMS gyroscope provided by the application improves the mechanical sensitivity.

Description

Technical Field

[0001] This invention relates to the fields of microelectromechanical systems and microinertial measurement technology, and in particular to a four-mass mechanical amplification MEMS gyroscope. Background Technology

[0002] Microelectromechanical (MEMS) gyroscopes are inertial sensors that measure rotational angular rate. They are fabricated using MEMS technology and have advantages such as small size, low cost, light weight, and ease of mass production, making them widely used.

[0003] Sensitivity is one of the key performance indicators (KPIs) of MEMS gyroscopes. To achieve high sensitivity in MEMS gyroscopes, while ensuring a high quality factor (Q value) and low frequency fragmentation, traditional linear vibration MEMS gyroscope research involves designing lever amplification structures to amplify the displacement of the MEMS gyroscope driving and detecting the structure. However, the mechanical sensitivity of multi-ring resonant and disk-type 2D rotating axisymmetric MEMS gyroscopes is related to the structural angular gain, effective mass, Q value, and resonant angular frequency, and the angular gain of rotating axisymmetric MEMS gyroscopes does not change with structural variations. Therefore, the main methods to improve the sensitivity of planar rotating axisymmetric MEMS gyroscopes are to increase the effective inertial mass or increase the area of ​​the sensing capacitor. Micro-hemispherical MEMS gyroscopes commonly use spherical shells with external electrodes for sensitive capacitance detection. Due to the large distance between the micro-hemispherical shell and the external electrode, the method of increasing the effective inertial mass at the edge of the hemispherical shell is usually adopted to improve mechanical sensitivity.

[0004] Current methods for increasing the mechanical sensitivity of MEMS gyroscopes generally involve increasing the movable inertial mass or the sensing capacitance, but these methods have limitations in improving sensitivity. Because the spacing between the capacitive comb teeth is on the order of micrometers, and the displacement change is on the order of nanometers, the signal change is extremely weak.

[0005] Therefore, there is an urgent need for a MEMS gyroscope that can enhance the detection signal and thus improve mechanical sensitivity. Summary of the Invention

[0006] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a four-mass mechanical amplification MEMS gyroscope to solve the problems of weak detection signal and low mechanical sensitivity of the prior art MEMS gyroscope.

[0007] To achieve the above and other related objectives, the present invention provides a four-mass mechanical amplification MEMS gyroscope, comprising:

[0008] Substrate;

[0009] A device layer is fixed on the substrate, and the device layer includes multiple interconnected structural units arranged in an array.

[0010] a driving structure in the structural unit, comprising a mass, a driving frame, elastic beams, a first folding beam, a first combined beam, a second combined beam and a third combined beam, the mass is provided with a plurality of elastic beams on both sides along the Y-axis direction, the mass is connected to the driving frame through the elastic beams, the first combined beam is located on the side of the mass away from the X-axis direction and is connected to the driving frame, and the first combined beam is connected to the balance bar through the first folding beam, the second combined beam is located on the side of the mass along the X-axis direction, and the third combined beam is located in the mass, and the X-axis and the Y-axis are perpendicular to each other;

[0011] a driving electrode structure in the structural unit, comprising a first capacitor and a second capacitor located on both sides of the first folding beam along the Y-axis direction and connected to the driving frame respectively, and a third capacitor located on the side of the second combined beam along the X-axis direction;

[0012] a detection structure in the structural unit, comprising a detection frame connected to the balance bar and a movable electrode frame connected to the detection frame through a second folding beam;

[0013] a detection beam in the structural unit and connected to the side of the movable electrode frame along the X-axis direction, and the intersection end points of the detection beam are connected to the mass through a single beam and a third combined beam;

[0014] a plurality of detection electrode units in the internal region of the detection frame and connected to the movable electrode frame, the detection electrode units comprising fourth, fifth, sixth and seventh capacitors arranged in an array.

[0015] Optionally, the device layer comprises four structural units connected to each other and arranged in a square form, two structural units arranged along the X-axis direction are symmetrically distributed about the center line of the substrate along the Y-axis direction, and two structural units arranged along the Y-axis direction are symmetrically distributed about the center line of the substrate along the X-axis direction.

[0016] Optionally, adjacent two structural units arranged along the X-axis direction are connected through a shared third folding beam, and adjacent two structural units arranged along the Y-axis direction are connected through a shared balance bar.

[0017] Optionally, the detection beams in two structural units arranged along the Y-axis direction are connected through a fourth folding beam connected to the detection beams.

[0018] Optionally, the shape of the detection beam comprises a V shape.

[0019] Optionally, the included angle between the first beam arm and the second beam arm of the detection beam ranges from 20 degrees to 40 degrees.

[0020] Optionally, the first beam arm is combined by a plurality of single straight beams; the second beam arm is combined by a plurality of single straight beams.

[0021] Optionally, the first capacitor is composed of a first movable electrode and a first fixed electrode connected with each other; the second capacitor is composed of a second movable electrode and a second fixed electrode connected with each other; the third capacitor is composed of a third movable electrode and a third fixed electrode connected with each other.

[0022] Optionally, the fourth capacitor is composed of a fourth fixed electrode and a fourth movable electrode surrounding the fourth fixed electrode; the fifth capacitor is composed of a fifth fixed electrode and a fifth movable electrode surrounding the fifth fixed electrode; the sixth capacitor is composed of a sixth fixed electrode and a sixth movable electrode surrounding the sixth fixed electrode; the seventh capacitor is composed of a seventh fixed electrode and a frequency tuning electrode surrounding the seventh fixed electrode.

[0023] Optionally, the first combined beam is connected with the mass body through a first fixed anchor point; the second combined beam is connected with the mass body through a second fixed anchor point.

[0024] Optionally, the balance lever is provided with a T-shaped beam and a third fixed anchor point connected with each other, and the third fixed anchor point is fixed on the balance lever through the T-shaped beam.

[0025] The four-mass mechanical amplification type MEMS gyroscope of the present application has the following beneficial effects: the detection beam is arranged in the MEMS gyroscope to effectively increase the displacement of the detection direction of the MEMS gyroscope, the displacement amplification factor of 373% or more is achieved by changing the included angle between the first beam arm and the second beam arm, and the mechanical sensitivity of the MEMS gyroscope is improved; four structure units connected to each other and arranged in a matrix form are arranged in the device layer of the MEMS gyroscope, and the two structure units arranged along the X-axis direction are symmetrically distributed about the center line of the Y-axis direction of the substrate, and the two structure units arranged along the Y-axis direction are symmetrically distributed about the center line of the X-axis direction of the substrate, forming a four-mass double-tongue type differential detection system, when the MEMS is in the detection mode, the design of simultaneous four-mass full-differential symmetric output can eliminate the influence of acceleration along the detection direction, can effectively eliminate the acceleration interference introduced from the outside, improves the environmental adaptability of the MEMS gyroscope, and improves the anti-vibration effect of the MEMS gyroscope; the first combined beam, the second combined beam, the third combined beam, the first folded beam, the second folded beam, the third folded beam, the detection beam and the elastic beam connecting the mass block, the driving frame and the detection frame are all decoupling beams, realizing full decoupling of the driving direction and the detection direction, eliminating the coupling error signal caused by the coupling of the Coriolis force motion, and coupling four inertia-sensitive mass blocks by using the decoupling beam, avoiding the case that the intrinsic frequency of the MEMS gyroscope does not match due to processing error. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 A structure schematic diagram of the four-mass mechanical amplification type MEMS gyroscope of the present application is shown.

[0027] Figure 2 A structure schematic diagram of the structure unit of the four-mass mechanical amplification type MEMS gyroscope of the present application is shown.

[0028] Figure 3 A partial structure schematic diagram of the four-mass mechanical amplification type MEMS gyroscope of the present application is shown.

[0029] Figure 4 A structure schematic diagram of the first combined beam of the four-mass mechanical amplification type MEMS gyroscope of the present application is shown.

[0030] Figure 5 Another partial structure schematic diagram of the four-mass mechanical amplification type MEMS gyroscope of the present application is shown.

[0031] Figure 6A third partial schematic view of the drive mode of the structural unit of the four-mass mechanically amplified MEMS gyroscope of the present invention.

[0032] Figure 7 A third partial schematic view of the drive mode of the structural unit of the four-mass mechanically amplified MEMS gyroscope of the present invention.

[0033] Figure 8 A third partial schematic view of the drive mode of the structural unit of the four-mass mechanically amplified MEMS gyroscope of the present invention.

[0034] Figure 9 A third partial schematic view of the drive mode of the structural unit of the four-mass mechanically amplified MEMS gyroscope of the present invention.

[0035] Figure 10 A third partial schematic view of the drive mode of the structural unit of the four-mass mechanically amplified MEMS gyroscope of the present invention.

[0036] Figure 11 A third partial schematic view of the drive mode of the structural unit of the four-mass mechanically amplified MEMS gyroscope of the present invention.

[0037] Figure 12 A third partial schematic view of the drive mode of the structural unit of the four-mass mechanically amplified MEMS gyroscope of the present invention.

[0038] Figure 13 A third partial schematic view of the drive mode of the structural unit of the four-mass mechanically amplified MEMS gyroscope of the present invention.

[0039] Figure 14 A third partial schematic view of the drive mode of the structural unit of the four-mass mechanically amplified MEMS gyroscope of the present invention.

[0040] Element No. 1 device layer, 11 structure unit, 2 driving structure, 21 mass, 22 driving frame, 23 elastic beam, 24 first folding beam, 25 first combined beam, 26 second combined beam, 27 third combined beam, 3 driving electrode structure, 31 first capacitor, 311 first movable electrode, 312 first fixed electrode, 32 second capacitor, 321 second movable electrode, 322 second fixed electrode, 33 third capacitor, 331 third movable electrode, 332 third fixed electrode, 4 detection structure, 41 detection frame, 42 movable electrode frame, 43 second folding beam, 5 detection beam, 51 first beam arm, 52 second beam arm, 6 detection electrode unit, 61 fourth capacitor, 611 fourth fixed electrode, 612 fourth movable electrode, 62 fifth capacitor, 621 fifth fixed electrode, 622 fifth movable electrode, 63 sixth capacitor, 631 sixth fixed electrode, 632 sixth movable electrode, 64 seventh capacitor, 641 seventh fixed electrode, 642 seventh frequency tuning electrode, 7 balance bar, 71 T-shaped beam, 8 single beam, 9 third folding beam, 10 fourth folding beam, 1a first fixed anchor point, 2a second fixed anchor point, 3a third fixed anchor point, 4a fourth fixed anchor point, 5a fifth fixed anchor point, 6a sixth fixed anchor point, 7a seventh fixed anchor point. DETAILED DESCRIPTION

[0041] The implementation of the present application is described below by specific embodiments, and other advantages and effects of the present application can be easily understood by those skilled in the art from the content disclosed in the present specification.

[0042] Please refer to Figures 1 to 14 . It should be understood that the structures, proportions, sizes, etc. shown in the drawings attached to the present specification are only used to cooperate with the content disclosed in the present specification for understanding and reading by those skilled in the art, and are not used to limit the defined conditions under which the present application can be implemented, so they do not have technical significance. Any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effects that can be produced by the present application and the purposes that can be achieved, should still fall within the scope of the technical content disclosed by the present application. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" used in the present specification are only for the convenience of clear understanding of the description, and are not used to limit the scope in which the present application can be implemented, and the change or adjustment of the relative relationship, without substantially changing the technical content, is also considered as the scope in which the present application can be implemented. Example 1

[0043] The present embodiment provides a four-mass mechanical amplification type MEMS gyroscope, as shown in Figures 1 to 2As shown, it is a structural schematic diagram of the MEMS gyroscope and a structural schematic diagram of the structural unit 11, the MEMS gyroscope comprises: a substrate (not shown), a device layer 1, a driving structure 2, a driving electrode structure 3, a detection structure 4, a detection beam 5 and a plurality of detection electrode units 6, wherein the device layer 1 is fixed on the substrate, the device layer 1 comprises a plurality of structural units 11 which are connected to each other and arranged in an array; the driving structure 2 is located in the structural unit 11 and comprises a mass 21, a driving frame 22, an elastic beam 23, a first folded beam 24, a first combined beam 25, a second combined beam 26 and a third combined beam 27, the mass 21 is provided with a plurality of elastic beams 23 on both sides along the Y-axis direction, the mass 21 is connected to the driving frame 22 through the elastic beam 23, the first combined beam 25 is located on the side of the mass 21 away from the X-axis direction and connected to the driving frame 22, and the first combined beam 25 is connected to the balance bar 7 through the first folded beam 24, the second combined beam 26 is located on one side of the mass 21 along the X-axis direction, the mass 21 surrounds the third combined beam 27, and the X-axis and the Y-axis are perpendicular to each other; the driving electrode structure 3 is located in the structural unit 11 and comprises a first capacitor 31 and a second capacitor 32 which are located on both sides of the first folded beam 24 along the Y-axis direction and connected to the driving frame respectively, and a third capacitor 33 which is located on one side of the second combined beam 26 along the X-axis direction; the detection structure 4 is located in the structural unit 11 and comprises a detection frame 41 connected to the balance bar 7 and a movable electrode frame 42 connected to the detection frame 41 through a second folded beam 43; the detection beam 5 is located in the structural unit 11 and connected to one side of the movable electrode frame 42 along the X-axis direction, and the intersection end points of the detection beam 5 are connected to the mass 21 through a single beam 8 and the third combined beam 27; a plurality of detection electrode units 6 are located in the internal region of the detection frame 41 and connected to the movable electrode frame 42, and the detection electrode units 6 comprise fourth, fifth, sixth and seventh capacitors 61, 62, 63 and 64 arranged in an array.

[0044] Specifically, the material of the substrate comprises silicon or other suitable materials.

[0045] Specifically, the shape and size of the substrate can be selected according to actual conditions without limitation under the condition of meeting the performance of the MEMS gyroscope.

[0046] As an example, the device layer 1 comprises four structural units 11 which are connected to each other and arranged in a square form, two structural units 11 arranged along the X-axis direction are symmetrically distributed about the center line of the substrate along the Y-axis direction, and two structural units 11 arranged along the Y-axis direction are symmetrically distributed about the center line of the substrate along the X-axis direction.

[0047] As an example, two adjacent structural units 11 arranged along the X-axis direction are connected through a third folded beam 9 in common; two adjacent structural units 11 arranged along the Y-axis direction are connected through the balance bar 7 in common.

[0048] Specifically, the third folded beam 9 is connected by four single straight beams U.

[0049] Specifically, the size and material of the third folded beam 9 can be selected according to actual conditions without limitation in the case of meeting the performance of the MEMS gyroscope.

[0050] Specifically, the balance bar 7 in common in two structural units 11 arranged along the Y-axis direction is fixed through the fourth fixed anchor point 4a and the fifth fixed anchor point 5a, so that the MEMS gyroscope remains balanced and stable during operation.

[0051] Specifically, the shape, size and material of the fourth fixed anchor point 4a can be selected according to actual conditions without limitation in the case of meeting the performance of the MEMS gyroscope; the shape, size and material of the fifth fixed anchor point 5a can be selected according to actual conditions without limitation.

[0052] Specifically, the shape, size and material of the drive frame 22 can be selected according to actual conditions without limitation in the case of meeting the performance of the MEMS gyroscope.

[0053] Specifically, the shape, size and material of the mass 21 can be selected according to actual conditions without limitation in the case of meeting the performance of the MEMS gyroscope.

[0054] Specifically, the number, shape, size and material of the elastic beam 23 can be selected according to actual conditions without limitation in the case of meeting the performance of the MEMS gyroscope. In this embodiment, four elastic beams 23 are provided on both sides of the mass 21 along the Y-axis direction, wherein two elastic beams 23 are provided on one side of the mass 21 along the Y-axis direction, and two elastic beams 23 are provided on the side of the mass 21 away from the Y-axis direction.

[0055] As an example, as shown in Figure 3 The first combined beam 25 is connected with the mass 21 through the first fixed anchor point 1a; the second combined beam 26 is connected with the mass 21 through the second fixed anchor point 2a.

[0056] Specifically, while meeting the performance requirements of the MEMS gyroscope, the shape, size, and material of the first fixed anchor point 1a can be selected according to the actual situation and are not limited here; the shape, size, and material of the second fixed anchor point 2a can be selected according to the actual situation and are not limited here.

[0057] Specifically, while meeting the performance requirements of the MEMS gyroscope, the shape, size, and material of the first combined beam 25 can be selected according to the actual situation and are not limited here.

[0058] Specifically, such as Figure 4 The diagram shows the structure of the first composite beam 25. The first composite beam 25 includes a first part 251 and a second part 252 connected to a base 253. The first part 251 and the second part 252 are fixed to the first base 253.

[0059] Specifically, the first part 251 is composed of six single straight beams connected together; the second part 252 is composed of six single straight beams connected together.

[0060] Specifically, while meeting the performance requirements of the MEMS gyroscope, the shape, size, and material of the second composite beam 26 can be selected according to the actual situation and are not limited here.

[0061] Specifically, the second composite beam 26 includes a third part 261 and a fourth part 262 connected to a second base 263, wherein the third part 261 and the fourth part 262 are fixed to the second base 263.

[0062] Specifically, the third part 261 is composed of six single straight beams connected together; the fourth part 262 is composed of six single straight beams connected together.

[0063] As an example, the balance bar 7 is provided with a connected T-beam 71 and a third and fourth fixed anchor point 3a, and the third fixed anchor point 3a is fixed to the balance bar 7 by the T-beam 71.

[0064] Specifically, while meeting the performance requirements of the MEMS gyroscope, the shape, size, and material of the balance bar 7 can be selected according to the actual situation and are not limited here; the shape, size, and material of the T-beam 71 can be selected according to the actual situation and are not limited here; the shape, size, and material of the third fixed anchor point 3a can be selected according to the actual situation and are not limited here.

[0065] Specifically, the third composite beam 27 is formed by connecting two longer single straight beams on the outer side and two shorter single straight beams on the inner side.

[0066] Specifically, the shape, size and material of the third combined beam 27 can be selected according to actual conditions without limitation in the case of meeting the performance of the MEMS gyroscope.

[0067] Specifically, the shape, size and material of the first folded beam 24 can be selected according to actual conditions without limitation in the case of meeting the performance of the MEMS gyroscope.

[0068] For example, the first capacitor 31 is composed of a first movable electrode 311 and a first fixed electrode 312 connected together; the second capacitor 32 is composed of a second movable electrode 321 and a second fixed electrode 322 connected together; and the third capacitor 33 is composed of a third movable electrode 331 and a third fixed electrode 332 connected together.

[0069] Specifically, the shape, size and material of the first movable electrode 311 can be selected according to actual conditions without limitation in the case of meeting the performance of the MEMS gyroscope; the shape, size and material of the second movable electrode 321 can be selected according to actual conditions without limitation in the case of meeting the performance of the MEMS gyroscope; and the shape, size and material of the third movable electrode 331 can be selected according to actual conditions without limitation in the case of meeting the performance of the MEMS gyroscope.

[0070] Specifically, the shape, size and material of the first fixed electrode 312 can be selected according to actual conditions without limitation in the case of meeting the performance of the MEMS gyroscope; the shape, size and material of the second fixed electrode 322 can be selected according to actual conditions without limitation in the case of meeting the performance of the MEMS gyroscope; and the shape, size and material of the third fixed electrode 332 can be selected according to actual conditions without limitation in the case of meeting the performance of the MEMS gyroscope.

[0071] Specifically, the size and material of the detection frame 41 can be selected according to actual conditions without limitation in the case of meeting the performance of the MEMS gyroscope.

[0072] Specifically, the size and material of the movable electrode frame 42 can be selected according to actual conditions without limitation in the case of meeting the performance of the MEMS gyroscope.

[0073] Specifically, the second folded beam 43 is composed of two single beams.

[0074] Specifically, the shape of the second folded beam 43 includes a U shape or other suitable shape.

[0075] Specifically, the material of the second folded beam 43 can be selected according to actual conditions without limitation in the case of meeting the performance of the MEMS gyroscope.

[0076] As an example, the shape of the detection beam 5 comprises a V shape or other suitable shape.

[0077] As an example, the included angle between the first beam arm 51 and the second beam arm 52 of the detection beam 5 ranges from 20 degrees to 40 degrees. In this embodiment, the included angle between the first beam arm 51 and the second beam arm 52 of the detection beam is 30 degrees.

[0078] Specifically, the first beam arm 51 and the second beam arm 52 of the detection beam 5 intersect at one end vertex to form a V-shaped detection beam, i.e., the detection beam 5 is designed to intersect and move.

[0079] As an example, the first beam arm 51 is composed of multiple single straight beams; the second beam arm 52 is composed of multiple single straight beams. In this embodiment, the first beam arm 51 is composed of three single straight beams, including three single straight beams with widths of 8 μm, 15 μm, and 8 μm, and lengths of 160 μm, 225 μm, and 160 μm, respectively; the second beam arm 52 is composed of three single straight beams, including three single straight beams with widths of 8 μm, 15 μm, and 8 μm, and lengths of 160 μm, 225 μm, and 160 μm, respectively.

[0080] Specifically, the first beam arm 51 is composed of three single straight beams, and the second beam arm 52 is composed of three single straight beams, which facilitates adjustment of the rigidity of the first beam arm 51 and the second beam arm 52 of the detection beam 5.

[0081] Specifically, the material of the single straight beam can be selected according to actual conditions without limitation, as long as the performance of the MEMS gyroscope is met.

[0082] Specifically, the detection beam effectively increases the displacement of the detection direction of the MEMS gyroscope, and a displacement amplification factor of 373% or more can be achieved by changing the included angle between the first beam arm 51 and the second beam arm 52, thereby improving the mechanical sensitivity of the MEMS gyroscope.

[0083] As an example, the detection beam 5 in the two structure units 11 arranged along the Y-axis direction is connected through a fourth folded beam 10 connected to the detection beam 5.

[0084] Specifically, the fourth folded beam 10 connects the movable electrode frame 42 located on both sides of the detection beam 5 along the X-axis direction.

[0085] Specifically, the fourth folded beam 10 is composed of two single straight beams connected in a U shape.

[0086] Specifically, the internal region of the detection frame 41 includes two detection electrode units 6, which are located on both sides of the detection beam 5 and are symmetrically distributed about the center line of the detection beam 5 along the Y-axis.

[0087] Specifically, the fourth capacitor 61, the fifth capacitor 62, the sixth capacitor 63, and the seventh capacitor 64 in the detection electrode unit 6 are arranged in a matrix, that is, in this embodiment, the four capacitors in the detection electrode unit 6 are arranged in a 2-row, 2-column configuration.

[0088] As an example, such as Figures 5 to 6 The figures show two partial structural diagrams of the MEMS gyroscope, one for a fourth fixed electrode 61 and the other for a third. The fourth capacitor 61 is composed of a fourth fixed electrode 611 and a fourth movable electrode 612 surrounding the fourth fixed electrode 611. The fifth capacitor 62 is composed of a fifth fixed electrode 621 and a fifth movable electrode 622 surrounding the fifth fixed electrode 621. The sixth capacitor 63 is composed of a sixth fixed electrode 631 and a sixth movable electrode 632 surrounding the sixth fixed electrode 631. The seventh capacitor 64 is composed of a seventh fixed electrode 641 and a frequency tuning electrode 642 surrounding the seventh fixed electrode 641.

[0089] Specifically, while meeting the performance requirements of the MEMS gyroscope, the shape, size, and material of the fourth movable electrode 612 can be selected according to the actual situation and are not limited here; the shape, size, and material of the fifth movable electrode 622 can be selected according to the actual situation and are not limited here; the shape, size, and material of the sixth movable electrode 632 can be selected according to the actual situation and are not limited here; the shape, size, and material of the frequency coordination electrode 642 can be selected according to the actual situation and are not limited here.

[0090] Specifically, while meeting the performance requirements of the MEMS gyroscope, the shape, size, and material of the fourth fixed electrode 611 can be selected according to the actual situation and are not limited here; the shape, size, and material of the fifth fixed electrode 621 can be selected according to the actual situation and are not limited here; the shape, size, and material of the sixth fixed electrode 631 can be selected according to the actual situation and are not limited here; the shape, size, and material of the seventh fixed electrode 641 can be selected according to the actual situation and are not limited here.

[0091] Specifically, the MEMS gyroscope also includes a sixth fixed anchor point 6a and a seventh fixed anchor point 7a, which are located between the four structural units 11.

[0092] Specifically, such as Figures 7 to 9 The diagrams shown are a schematic diagram of the driving mode of the structural unit of the MEMS gyroscope, a partial schematic diagram of one driving mode of the structural unit of the MEMS gyroscope, and another partial schematic diagram of the driving mode of the structural unit of the MEMS gyroscope. When driving the MEMS gyroscope, an in-phase AC voltage is applied to the first capacitor 31 of the two structural units 11 arranged along the X-axis in the upper half of the Y-axis, and a DC bias voltage is applied to the two mass blocks 21 respectively, which can generate a driving electrostatic force. The first combined beam 25, the second combined beam 26, the third combined beam 27, and the third folding beam 9 in the two structural units 11 perform opening and closing movements within the driving frame 22, and the movement states of the beams in the two structural units 11 are opposite. The two mass blocks 21 in the two structural units 11 located in the upper half of the Y-axis oscillate in opposite directions. An in-phase AC voltage is applied to the first capacitor 31 in the two structural units 11 located in the lower half of the Y-axis along the X-axis direction, and a DC bias voltage is applied to the two mass blocks 21 to generate a driving electrostatic force. The first combined beam 25, the second combined beam 26, the third combined beam 27, and the third folded beam 9 in the two structural units 11 located in the lower half of the Y-axis move in the opposite direction to the motion state of the first combined beam 25, the second combined beam 26, the third combined beam 27, and the third folded beam 9 in the driving frame 22. This causes the two mass blocks 21 in the two structural units 11 located in the lower half of the Y-axis to oscillate in opposite directions.

[0093] Specifically, when the MEMS gyroscope vibrates, the third capacitors 33, which are symmetrically distributed about the X-axis in the MEMS gyroscope, change in opposite directions. Differential analysis of the driving mode of the MEMS gyroscope can be achieved by subtracting the capacitance values ​​of the two third capacitors 33 in the two structural units 11 that are symmetrically distributed about the X-axis. In this embodiment, the resonant frequency of the driving mode of the MEMS gyroscope is 13863Hz.

[0094] Specifically, such as Figures 10-14As shown, the detection mode schematic diagram of the structural unit of the MEMS gyroscope, one kind of partial schematic diagram of the detection mode of the structural unit of the MEMS gyroscope, another kind of partial schematic diagram of the detection mode of the structural unit of the MEMS gyroscope, the third kind of partial schematic diagram of the detection mode of the structural unit of the MEMS gyroscope and the fourth kind of partial schematic diagram of the detection mode of the structural unit of the MEMS gyroscope, when the MEMS gyroscope is in the driving mode, the angular velocity along the Z axis direction is applied by the outside, at this time, the two mass blocks 21 in the two structural units 11 arranged along the X axis direction on the upper half of the Y axis will be subjected to the Coriolis force in the direction opposite to the Y axis direction, the mass blocks 21 in the two structural units 11 on the lower half of the Y axis are subjected to the Coriolis force in the direction opposite to the corresponding two mass blocks 21 in the structural units 11 on the upper half of the Y axis. The Coriolis force received by the mass block 21 is conducted to the detection frame 41 through the detection beam 5, so that the movable electrode frame 42 inside the detection frame 41 generates opposite oscillation motion; when the MEMS gyroscope is in the detection mode motion, the change direction of the fourth capacitors 61 in the two structural units 11 on the same side of the center line of the detection beam 5 along the Y axis direction is the same, and the two fourth capacitors 61 in the structural units 11 symmetric about the center line of the detection beam 5 along the Y axis direction form a differential detection output, which suppresses the error caused by the detection acceleration, and the reverse voltage applied on the fifth capacitor 62 and the sixth capacitor 63 can generate electrostatic force, and the electrostatic force is opposite to the Coriolis force, which can suppress the motion of the MEMS gyroscope in the detection mode, and realize the closed-loop control of the MEMS gyroscope. In this embodiment, the detection mode resonance frequency of the MEMS gyroscope is 13919Hz.

[0095] Specifically, by arranging four structural units 11 connected with each other and arranged in a square form in the device layer of the MEMS gyroscope, and the two structural units 11 arranged along the X axis direction are symmetrically distributed about the center line of the substrate along the Y axis direction, and the two structural units 11 arranged along the Y axis direction are symmetrically distributed about the center line of the substrate along the X axis direction, a four-mass double-tongue differential detection system is formed, and when the MEMS is in the detection mode, the design of the four-mass full-differential symmetric output can eliminate the influence of the acceleration along the detection direction, and the external introduced acceleration interference can be effectively eliminated, thereby improving the environmental adaptability of the MEMS gyroscope and improving the anti-vibration effect of the MEMS gyroscope.

[0096] Specifically, as Figures 10-12As shown, when the upper and lower ends of the detection beam 5 are subjected to a force in the Y-axis direction, the detection beam 5 will produce displacement in the Y-axis direction. Due to the V-shaped and movable design of the detection beam 5, displacement in the X-axis direction will be produced at the other end opening position of the detection beam 5, and the displacement in the X-axis direction will be greater than the displacement in the Y-axis direction. If the displacement in the Y-axis direction is set as v, and the displacement in the X-axis direction is set as u, it can be obtained that, where θ is half of the included angle between the first beam arm 51 and the second beam arm 52 in the detection beam 5, and α is the magnification of the mechanical sensitivity. In the present embodiment, the included angle is 30 degrees, and the magnification α = 3.73. By adjusting the included angle between the first beam arm 51 and the second beam arm 52, the magnification of the mechanical sensitivity can be changed.

[0097] Specifically, the first combined beam 25, the second combined beam 26, the third combined beam 27, the first folding beam 24, the second folding beam 43, the third folding beam 9, the elastic beam 23, and the detection beam 5 used for connecting the mass block 21, the driving frame 22, and the detection frame 41 all belong to decoupling beams. The connection is achieved by using decoupling beams, which realizes full decoupling of the driving direction and the detection direction, eliminates the coupling error signal caused by the coupling of the Coriolis force motion, and couples the four inertia-sensitive mass blocks 21 by using the decoupling beams, thereby avoiding the situation that the intrinsic frequency of the MEMS gyroscope does not match due to the machining error.

[0098] The four-mass mechanical amplification type MEMS gyroscope of the embodiment effectively increases the displacement of the MEMS gyroscope detection direction by setting the detection beam 5, realizes a displacement amplification ratio of 373% or more by changing the included angle between the first beam arm 51 and the second beam arm 52, and improves the mechanical sensitivity of the MEMS gyroscope; four structure units 11 are arranged in the device layer 1 of the MEMS gyroscope, and the two structure units 11 arranged along the X-axis direction are symmetrically distributed about the center line of the substrate along the Y-axis direction, and the two structure units 11 arranged along the Y-axis direction are symmetrically distributed about the center line of the substrate along the X-axis direction, forming a four-mass double-tongue differential detection system; when the MEMS is in a detection mode, the design of simultaneously four-mass full-differential symmetric output can eliminate the influence of acceleration along the detection direction, can effectively eliminate the acceleration interference introduced from the outside, and improves the environmental adaptability of the MEMS gyroscope and the anti-vibration effect of the MEMS gyroscope; by setting the first combined beam 25, the second combined beam 26, the third combined beam 27, the first folding beam 24, the second folding beam 43, the third folding beam 9, the detection beam 5 and the elastic beam 23 connecting the mass block 21, the driving frame 22 and the detection frame 41, all of which are decoupling beams, full decoupling of the driving direction and the detection direction is realized, the coupling error signal caused by the Coriolis force motion coupling is eliminated, and the four inertia-sensitive mass blocks 21 are coupled by using the decoupling beam, avoiding the case that the intrinsic frequency of the MEMS gyroscope does not match due to processing errors.

[0099] In summary, the application effectively increases the displacement of the detection direction of the MEMS gyroscope by arranging the detection beam in the MEMS gyroscope, realizes the displacement amplification of 373% and above by changing the included angle between the first beam arm and the second beam arm, and improves the mechanical sensitivity of the MEMS gyroscope; four structure units connected with each other and arranged in a square form are arranged in the device layer of the MEMS gyroscope, and the two structure units arranged along the X-axis direction are symmetrically distributed about the center line of the substrate along the Y-axis direction, and the two structure units arranged along the Y-axis direction are symmetrically distributed about the center line of the substrate along the X-axis direction, to constitute a four-mass double-tongue differential detection system; when the MEMS is in the detection mode, the design of the four-mass full-differential symmetric output can eliminate the influence of the acceleration along the detection direction, can effectively eliminate the acceleration interference introduced from the outside, and improves the environmental adaptability of the MEMS gyroscope and the anti-vibration effect of the MEMS gyroscope; the first combined beam, the second combined beam, the third combined beam, the first folding beam, the second folding beam, the third folding beam, the detection beam and the elastic beam connected with the mass block, the driving frame and the detection frame are all decoupling beams, realizing full decoupling of the driving direction and the detection direction, eliminating the coupling error signal caused by the coupling of the Coriolis force motion, and coupling the four inertia-sensitive mass bodies by the decoupling beam, avoiding the case that the intrinsic frequency of the MEMS gyroscope is not matched due to the processing error. Therefore, the application effectively overcomes the various shortcomings in the prior art and has high industrial utilization value.

[0100] The above embodiments only exemplarily illustrate the principles and effects of the application, and are not used to limit the application. Any person skilled in the art can modify or change the above embodiments without departing from the spirit and scope of the application. Therefore, all equivalent modifications or changes made by those skilled in the art without departing from the spirit and technical thought disclosed by the application should be covered by the claims of the application.

Claims

1. A four-mass mechanical-amplification MEMS gyroscope, characterized by, The application relates to a display device, which comprises: a substrate; a device layer fixed on the substrate, the device layer comprising a plurality of structural units connected with each other and arranged in an array; a driving structure in the structural unit, which comprises a mass, a driving frame, an elastic beam, a first folding beam, a first combined beam, a second combined beam and a third combined beam, the mass being provided with a plurality of elastic beams on both sides along the Y-axis direction, the mass being connected to the driving frame through the elastic beams, the first combined beam being located on the side of the mass away from the X-axis direction and connected to the driving frame, the first combined beam being connected to a balance bar through the first folding beam, the second combined beam being located on the side of the mass along the X-axis direction, the third combined beam being surrounded by the mass, and the X-axis and the Y-axis being perpendicular to each other; a driving electrode structure in the structural unit, which comprises a first capacitor and a second capacitor connected with the driving frame on both sides of the first folding beam along the Y-axis direction, and a third capacitor located on the side of the second combined beam along the X-axis direction; a detection structure in the structural unit, which comprises a detection frame connected with the balance bar and a movable electrode frame connected with the detection frame through a second folding beam; a detection beam in the structural unit, which is connected with the side of the movable electrode frame along the X-axis direction, the cross end points of the detection beam being connected to the mass through a single beam and a third combined beam, the shape of the detection beam comprising a V shape, and the included angle between the first beam arm and the second beam arm of the detection beam ranging from 20 degrees to 40 degrees; a plurality of detection electrode units in the internal region of the detection frame and connected with the movable electrode frame, the detection electrode units comprising fourth, fifth, sixth and seventh capacitors arranged in an array, wherein the device layer comprises four structural units connected with each other and arranged in a square form, two structural units arranged along the X-axis direction being symmetrically distributed about the center line of the substrate along the Y-axis direction, two structural units arranged along the Y-axis direction being symmetrically distributed about the center line of the substrate along the X-axis direction, adjacent two structural units arranged along the X-axis direction being connected through a shared third folding beam, adjacent two structural units arranged along the Y-axis direction being connected through a shared balance bar, and the detection beams in the two structural units arranged along the Y-axis direction being connected through a fourth folding beam connected with the detection beams.

2. The four-mass mechanical-amplification MEMS gyroscope of claim 1, wherein: The first beam arm is composed of a plurality of single straight beams; and the second beam arm is composed of a plurality of single straight beams.

3. The four-mass mechanical-amplification MEMS gyroscope of claim 1, wherein: The first capacitor is composed of a first movable electrode and a first fixed electrode connected with each other; the second capacitor is composed of a second movable electrode and a second fixed electrode connected with each other; and the third capacitor is composed of a third movable electrode and a third fixed electrode connected with each other.

4. The four-mass mechanical-amplification MEMS gyroscope of claim 1, wherein: The fourth capacitor is composed of a fourth fixed electrode and a fourth movable electrode surrounding the fourth fixed electrode; the fifth capacitor is composed of a fifth fixed electrode and a fifth movable electrode surrounding the fifth fixed electrode; the sixth capacitor is composed of a sixth fixed electrode and a sixth movable electrode surrounding the sixth fixed electrode; and the seventh capacitor is composed of a seventh fixed electrode and a frequency tuning electrode surrounding the seventh fixed electrode.

5. The four-mass mechanical-amplification MEMS gyroscope of claim 1, wherein: The first composite beam is connected to the mass body through a first fixed anchor point; and the second composite beam is connected to the mass body through a second fixed anchor point.

6. The four-mass mechanical-amplification MEMS gyroscope of claim 1, wherein: A T-shaped beam and a third fixed anchor point are connected to the balance bar, and the third fixed anchor point is fixed to the balance bar through the T-shaped beam.

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