MEMS resonator and electronic device

Abstract

The present application relates to the technical field of micro-electro-mechanics. Provided are a MEMS resonator, a resonant system, and an electronic device. The MEMS resonator comprises a connecting rod and at least one resonant unit having a ring structure, wherein the ring structure comprises an outer ring surface and an inner ring surface, and the connecting rod is connected to the outer ring surface; the size of the outer ring surface on a first axis is A, and the size of the outer ring surface on a second axis is B, A not being equal to B; the size of the inner ring surface on the first axis is C, and the size of the inner ring surface on the second axis is D, C not being equal to D; on the first axis, the distance between the outer ring surface and the inner ring surface is Δa, and on the second axis, the distance between the outer ring surface and the inner ring surface is Δb, Δa not being equal to Δb; and the ring structure is symmetrically arranged about both the first axis and the second axis. Due to the design including the non-equiaxial length of the outer ring surface, the non-equiaxial length of the inner ring surface, and the non-uniform width of the ring width, the difference in temperature sensitivity caused by the material anisotropy of the resonant unit can be fully utilized to broaden the temperature sensitivity of the resonator.

Description

MEMS resonators, electronic devices

[0001] This application claims priority to Chinese Patent Application No. 202510390401.0, filed with the State Intellectual Property Office of China on March 28, 2025, entitled "MEMS Resonator, Electronic Device", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of microelectromechanical technology, and more particularly to a MEMS resonator and electronic device. Background Technology

[0003] Micro-electro-mechanical systems (MEMS) resonators are components based on the mechanical resonance effect. They are miniature resonators manufactured using advanced semiconductor processing technology, integrating microsensors, microactuators, micromechanical structures, signal processing units, and control circuits. They offer advantages such as small size, light weight, low power consumption, low cost, stable performance, and high integration. MEMS resonators are the most fundamental components constituting MEMS oscillators, clock generators, and various resonant sensors, and have a very wide range of applications.

[0004] Different types of MEMS resonators, such as resonant MEMS and temperature-compensated MEMS, have different requirements for temperature sensitivity. Resonant MEMS require lower temperature sensitivity, while temperature-compensated MEMS require higher temperature sensitivity. However, in existing technologies, constructing MEMS resonant devices with different temperature sensitivities presents technical challenges. Summary of the Invention

[0005] This application provides a MEMS resonator and an electronic device. The main objective is to provide a MEMS resonator that can be constructed with different temperature sensitivities.

[0006] To achieve the above objectives, the embodiments of this application adopt the following technical solutions:

[0007] In one aspect, this application provides a MEMS resonator, which, for example, can be used in a clock system.

[0008] The MEMS resonator includes a connecting rod and at least one resonant unit, each of which is a ring structure. The ring structure includes an outer ring surface and an inner ring surface, and the connecting rod is connected to the outer ring surface. The outer ring surface has a dimension A on a first axis and a dimension B on a second axis. Dimension A on the first axis is greater than the dimension on any other axis. Dimension B on the second axis is less than the dimension on any other axis. The inner ring surface has a dimension C on the first axis and a dimension D on the second axis, where C and D are not equal. The distance between the outer and inner ring surfaces on the first axis is Δa, and the distance between them on the second axis is Δb, where Δa is greater than Δb. The first axis is perpendicular to the second axis, and the ring structure is symmetrically arranged about both the first and second axes.

[0009] In the MEMS resonator provided in this application, the outer ring surface has a non-equiaxial length because its dimension A on the first axis is larger than its dimension on any other axis; its dimension B on the second axis is smaller than its dimension on any other axis; and its dimension C on the first axis is not equal to its dimension D on the second axis. Similarly, the inner ring surface also has a non-equiaxial length because its non-equiaxial outer and inner ring surfaces fully utilize the temperature sensitivity differences caused by the anisotropy of the resonant unit material. This broadens the temperature sensitivity of the resonator, allowing for a wider temperature sensitivity adjustment range. For example, by adjusting the dimensions of the outer and inner ring surfaces on the first or second axis, the symmetry of the resonant unit shape can be changed to match the anisotropy of the resonant unit material, thereby increasing or decreasing temperature sensitivity. This can be applied to resonant MEMS units with low temperature sensitivity, or to temperature-compensated MEMS resonant units with high temperature sensitivity.

[0010] In the MEMS resonator provided in this application, the distance between the outer and inner ring surfaces is Δa, and on the second axis, the distance between the outer and inner ring surfaces is Δb, where Δa is greater than Δb. This can be understood as the ring width of the resonant unit's ring structure being non-uniform. The non-uniform ring structure can further increase the difference in length and width, thereby further enhancing the temperature sensitivity caused by the material's anisotropy. Furthermore, during vibration, the vibration amplitudes of the long axis end (which can be considered the first axis) and the short axis end (which can be considered the second axis) differ to some extent. By changing the ring width between the long and short axis ends, the relative stiffness between the two ends can be changed, thereby adjusting the mode shape and making the capacitance change amplitude during vibration larger, further optimizing the resonator's performance.

[0011] In one possible implementation, the dimension C of the inner toroidal surface on the first axis is greater than the dimension of the inner toroidal surface on any other axis, and the dimension D of the inner toroidal surface on the second axis is less than the dimension of the inner toroidal surface on any other axis; or, the dimension C of the inner toroidal surface on the first axis is less than the dimension of the inner toroidal surface on any other axis, and the dimension D of the inner toroidal surface on the second axis is greater than the dimension of the inner toroidal surface on any other axis.

[0012] In one implementation of this structure, the dimension A of the outer toroidal surface on the first axis is greater than the dimension of the outer toroidal surface on any other axis; the dimension B of the outer toroidal surface on the second axis is less than the dimension of the outer toroidal surface on any other axis; and the dimension C of the inner toroidal surface on the first axis is greater than the dimension of the inner toroidal surface on any other axis, and the dimension D of the inner toroidal surface on the second axis is less than the dimension of the inner toroidal surface on any other axis. This structure can be regarded as the major axis end of the outer toroidal surface corresponding to the major axis end of the inner toroidal surface, and the minor axis end of the outer toroidal surface corresponding to the minor axis end of the inner toroidal surface.

[0013] In another implementation of this structure, the dimension A of the outer toroidal surface on the first axis is greater than the dimension of the outer toroidal surface on any other axis; the dimension B of the outer toroidal surface on the second axis is less than the dimension of the outer toroidal surface on any other axis; and the dimension C of the inner toroidal surface on the first axis is less than the dimension of the inner toroidal surface on any other axis, while the dimension D of the inner toroidal surface on the second axis is greater than the dimension of the inner toroidal surface on any other axis. This structure can be viewed as the major axis end of the outer toroidal surface corresponding to the minor axis end of the inner toroidal surface, and the minor axis end of the outer toroidal surface corresponding to the major axis end of the inner toroidal surface.

[0014] Whether it is a temperature-compensated MEMS resonant unit or a resonant MEMS resonant unit, by changing the degree of symmetry of the realization structure and coordinating it with the anisotropy of the resonant unit material, the temperature sensitivity can be improved or reduced, as well as the device's response sensitivity to external force impacts can be reduced, thereby improving the device's reliability.

[0015] In one possible implementation, the distance Δa between the outer and inner toroidal surfaces on the first axis is greater than the distance between the outer and inner toroidal surfaces on any other axis; and the distance Δb between the outer and inner toroidal surfaces on the second axis is less than the distance between the outer and inner toroidal surfaces on any other axis.

[0016] This can be understood as follows: the distance between the outer and inner annular surfaces is the largest at the end of the long axis and the smallest at the end of the short axis. In this way, the relative stiffness between the two ends can be changed by further changing the annular width between the long and short axis ends, thereby further adjusting the mode shape and making the capacitance change amplitude during vibration greater.

[0017] In one possible implementation, the outer torus is an ellipse, and / or the inner torus is an ellipse.

[0018] In this example, when at least one of the outer or inner toroidal surfaces is elliptical, the quality factor Q of the resonator can be improved compared to a ring structure with sharp edges. Furthermore, in the vibration of an elliptical ring, the deformation amplitude at the major axis end is greater than that at the minor axis end. If the width of the major axis end is increased, making its stiffness relatively greater than that of the minor axis end, more of the ring portion between the major and minor axis ends can have an amplitude closer to that at the major axis end, thus making the deformation more significant.

[0019] In one possible implementation, the material of the resonant unit includes silicon and a doped material, wherein the doped material includes at least one of phosphorus, boron, and arsenic.

[0020] Among the available methods, silicon materials can be fabricated by varying the types or concentrations of doped materials, which can affect the anisotropic temperature characteristics of silicon materials. For example, when doped with boron, different concentrations can yield silicon-based materials with different temperature sensitivities.

[0021] In one feasible implementation, the resonant unit includes a temperature-compensated MEMS resonant unit and a resonant MEMS resonant unit; the temperature-compensated MEMS resonant unit... Greater than the resonant MEMS resonant unit

[0022] This can be understood as follows: the aspect ratio of the outer ring of the temperature-compensated MEMS resonant unit is greater than that of the resonant MEMS resonant unit. In other words, the outer ring shape of the temperature-compensated MEMS resonant unit is flatter than that of the resonant MEMS resonant unit. Using this type of resonant MEMS resonant unit can reduce the temperature sensitivity difference caused by the anisotropy of the resonant unit material, thereby reducing the temperature sensitivity of the temperature-compensated device and making the output signal of the temperature-compensated device more stable.

[0023] In one feasible approach, in a temperature-compensated MEMS resonant unit... In a resonant MEMS resonant unit,

[0024] when Under these conditions, the periodic contraction or expansion of the resonant unit can be guaranteed.

[0025] In one feasible approach, a temperature-compensated MEMS resonant unit... Resonant MEMS resonant unit,

[0026] This can be understood as follows: In temperature-compensated MEMS resonant units, greater sensitivity to temperature changes is required, and therefore, [the following is used]... This allows for greater variation in temperature sensitivity caused by the anisotropy of the resonant unit material, enhancing the temperature sensitivity of the temperature-compensated MEMS resonant unit and enabling timely compensation. In resonant MEMS resonant units, a more resistant response to temperature changes is required. This can weaken the temperature sensitivity differences caused by the anisotropy of the resonant unit material, thereby reducing the temperature sensitivity of the resonant MEMS resonant unit and making the output signal of the resonator more stable.

[0027] In one feasible implementation, the resonant unit includes a temperature-compensated MEMS resonant unit and a resonant MEMS resonant unit; the temperature-compensated MEMS resonant unit... Greater than the resonant MEMS resonant unit

[0028] This can be understood as follows: the aspect ratio of the inner ring of the temperature-compensated MEMS resonant unit is greater than that of the resonant MEMS resonant unit. In other words, the shape of the inner ring of the temperature-compensated MEMS resonant unit is flatter than that of the resonant MEMS resonant unit. By adopting this structure, the temperature sensitivity difference caused by the anisotropy of the resonant unit material can be reduced, thereby reducing the temperature sensitivity of the temperature-compensated device and making the output signal of the temperature-compensated device more stable.

[0029] In one feasible approach, in a temperature-compensated MEMS resonant unit... In a resonant MEMS resonant unit, 4.

[0030] In one feasible approach, a temperature-compensated MEMS resonant unit... Resonant MEMS resonant unit,

[0031] In one feasible implementation, the resonant unit includes a temperature-compensated MEMS resonant unit and a resonant MEMS resonant unit; the temperature-compensated MEMS resonant unit... Greater than the resonant MEMS resonant unit Δd is the difference in ring width, Δd=Δa-Δb.

[0032] That is, the ratio of the ring width difference of the temperature-compensated MEMS resonant unit is greater than the ratio of the ring width difference of the resonant MEMS resonant unit.

[0033] In one feasible approach, the temperature-compensated MEMS resonant unit has a value of 0 < Δd / Δb ≤ 5; the resonant MEMS resonant unit has a value of 0 < Δd / Δb ≤ 3.

[0034] This can be understood as follows: In temperature compensation devices, since 0 < Δd / Δb ≤ 5, that is, the resonant unit has a larger ring width difference ratio, the difference between the resonant unit on the first axis and the second axis can be further increased, the temperature sensitivity brought about by the anisotropy of the resonant unit material can be further strengthened, and the temperature compensation device can be enhanced.

[0035] In resonant devices, 0 < Δd / Δb ≤ 3, which means that the ratio of the ring width difference of the resonant device is less than the ratio of the ring width difference of the temperature compensation device. 0 < Δd / Δb ≤ 3 can weaken the temperature sensitivity difference caused by the anisotropy of the resonant unit material, thereby reducing the temperature sensitivity of the temperature compensation device.

[0036] In addition, when the ring structure vibrates, the vibration amplitude on the first axis and the second axis is different. By changing the ring width on the first axis and the second axis, the stiffness of the resonant unit on the first axis and the second axis can be changed, and the mode shape of the resonant unit can be adjusted, so that the capacitance change amplitude during vibration is greater.

[0037] In one possible implementation, the resonant unit includes a temperature-compensated MEMS resonant unit and a resonant MEMS resonant unit, both of which are made of silicon; the angle between the crystal orientation of the silicon material in the temperature-compensated MEMS resonant unit and the extension direction of the connecting rod is 45°; or, the angle between the crystal orientation of the silicon material in the resonant MEMS resonant unit and the extension direction of the connecting rod is 0°.

[0038] In temperature compensation devices, since the angle between the crystal orientation of silicon material and the connecting rod is 45°, the crystal orientation is conducive to the temperature compensation device remaining sensitive to temperature drift, and can effectively compensate for the resonant device at different temperatures.

[0039] In resonant devices, since the angle between the crystal orientation of silicon material and the connecting rod is 0°, the crystal orientation helps the ring structure to remain stable in response to temperature changes, and the vibration frequency will not be affected by temperature changes.

[0040] In one possible implementation, the connecting rod extends along a first axis, and the connection position of the connecting rod to the outer ring surface is on the first axis; or, the connecting rod extends along a second axis, and the connection position of the connecting rod to the outer ring surface is on the second axis; the dimension C of the inner ring surface on the first axis is greater than the dimension of the inner ring surface on any other axis, and the dimension D of the inner ring surface on the second axis is smaller than the dimension of the inner ring surface on any other axis.

[0041] That is, the connecting rod is connected to the long axis end of the ring structure, or it can be connected to the short axis end of the ring structure. The connecting rod is parallel to the long axis or the short axis. In this way, the resonant unit can maintain mode symmetry when vibrating. In addition, for example, connecting the connecting rod to the long axis end of the ring structure can also optimize the temperature-sensitive design.

[0042] In one possible implementation, the cross-section of the connecting rod is rectangular; or, the connecting rod is solid.

[0043] For example, when the connecting rod adopts a solid structure, it can achieve low thermoelastic loss, which makes the MEMS resonator have a higher quality factor Q.

[0044] In one feasible approach, the length of the connecting rod is approximately one-quarter of the resonant wavelength of the MEMS resonator; one end of the connecting rod is connected to the outer ring surface of the resonant unit, and the other end is connected to the base.

[0045] When the length of the connecting rod is about one-quarter of the resonant wavelength of the MEMS resonator, the amplitude at the coupling point between the connecting rod and the base can be made to be basically zero. This results in low support loss of the connecting rod, giving the MEMS resonator a higher quality factor Q and improving its performance.

[0046] In one possible implementation, the connecting rod includes a connecting portion connected to the outer annular surface and a suspended portion connected to the connecting portion, wherein the cross-sectional area of ​​the connecting portion is smaller than the cross-sectional area of ​​the suspended portion.

[0047] This can be understood as follows: the smaller area at the connection point between the connecting rod and the resonant unit allows for lower support loss of the connecting rod, resulting in a higher quality factor Q for the MEMS resonator and improving its performance.

[0048] In one feasible approach, the outer wall of the connecting portion is recessed compared to the outer wall of the suspended portion, such that the cross-sectional area of ​​the connecting portion is smaller than that of the suspended portion.

[0049] In this example, the cross-sectional area of ​​the part where the connecting rod connects to the resonant unit is reduced by setting a recessed structure on the outer wall surface.

[0050] In one feasible manner, the dimensions of both the outer and inner annular surfaces are maximized along the first axis, and minimized along the second axis; the distance between the outer and inner annular surfaces gradually decreases between the first and second axes.

[0051] In one possible configuration, the ring structure is symmetrically arranged about a first axis and about a second axis; or, the ring structure is symmetrically arranged about a center point where the first and second axes intersect.

[0052] A symmetrical resonant unit can have a symmetrical mode shape.

[0053] In one possible implementation, the MEMS resonator includes multiple resonant elements arranged in an array; the multiple resonant elements are symmetrically arranged about a first axis; and the multiple resonant elements are symmetrically arranged about a second axis.

[0054] Using multiple resonant units can expand the temperature sensitivity range. Furthermore, the symmetrical arrangement of the multiple resonant units ensures synchronization and stability during vibration.

[0055] Secondly, this application also provides an electronic device, which includes a MEMS resonator as described in any of the above implementations; the electronic device also includes peripheral circuitry, and the MEMS resonator is electrically connected to the peripheral circuitry.

[0056] Because the electronic device incorporates the MEMS resonator described above, the ring structure within the resonator employs a non-equiaxial length and non-uniform width design. This allows for full utilization of the temperature sensitivity differences arising from the anisotropy of the resonant unit material, thereby broadening the resonator's temperature sensitivity and providing a wider temperature sensitivity adjustment range. Furthermore, the ring width of the resonant unit's ring structure is non-uniform; this non-uniform width further increases the difference in length and width, further enhancing the temperature sensitivity due to material anisotropy. Additionally, during vibration, the amplitude of vibration at the long axis end (which can be considered the first axis) and the short axis end (which can be considered the second axis) differs. By altering the ring width at the long and short axis ends, the relative stiffness between the two ends can be changed, thereby adjusting the mode shape and resulting in a larger capacitance change amplitude during vibration, further optimizing the resonator's performance. Attached Figure Description

[0057] Figure 1 is a schematic diagram of the structure of a MEMS resonator according to an example of this application;

[0058] Figure 2 is a partial structural schematic diagram of a MEMS resonator according to an example of this application;

[0059] Figure 3 is a partial structural schematic diagram of a MEMS resonator according to an example of this application;

[0060] Figure 4 is a schematic diagram of the structure of a resonant unit in a MEMS resonator according to an example of this application;

[0061] Figure 5 is a schematic diagram of the structure of a resonant unit in a MEMS resonator according to an example of this application;

[0062] Figure 6 is a schematic diagram of the structure of a resonant unit in a MEMS resonator according to an example of this application;

[0063] Figure 7 is a schematic diagram of the structure of a resonant unit in a MEMS resonator according to an example of this application;

[0064] Figure 8 is a schematic diagram of the structure of a resonant unit in a MEMS resonator according to an example of this application;

[0065] Figure 9 is a schematic diagram of the structure of a resonant unit in a MEMS resonator according to an example of this application;

[0066] Figure 10 is a schematic diagram of the structure of a resonant unit in a MEMS resonator according to an example of this application;

[0067] Figure 11 is a schematic diagram of the structure of multiple temperature-compensated MEMS resonant units in a MEMS resonator according to an example of this application.

[0068] Figure 12 is a schematic diagram of the structure of multiple resonant MEMS resonant units in a MEMS resonator according to an example of this application.

[0069] Figure 13 is a schematic diagram of the connection relationship between a resonant unit and a connecting rod in a MEMS resonator according to an example of this application.

[0070] Figure 14 is a schematic diagram of the connection relationship between a resonant unit and a connecting rod in a MEMS resonator according to an example of this application.

[0071] Reference numerals: 100-Resonant structure; 200-First support pillar; 300-Substrate; 400-Cap; 500-Second support pillar; 101-Resonant unit; 102-First electrode; 103-Second electrode; 104-Connecting rod; 105-Base; 106-Mass block; 104A-Connecting part; 104B-Suspended part. Detailed Implementation

[0072] The solutions involved in the embodiments of this application will be described below with reference to the accompanying drawings.

[0073] This application provides an electronic device that may include communication devices (e.g., base stations, mobile phones), wireless charging devices, medical devices, radar, navigation devices, radio frequency (RF) devices, etc. Alternatively, the electronic device may include a mobile phone, tablet computer, smart wearable products (e.g., smartwatches, smart bracelets), virtual reality (VR) terminal devices, augmented reality (AR) terminal devices, or vehicles, etc. This application does not impose any special limitations on the specific form of the electronic device.

[0074] The electronic device in the above example may include a resonator, which can be used as an oscillator, filter, or sensor, etc. Peripheral circuitry is electrically connected to the resonator. When the resonator is used as an oscillator, such a resonant system can be a clock system; when the resonator is used as a filter, such a resonant system can be an antenna system in communication; or, when used as a sensor, such a resonant system can be a sensor system.

[0075] The resonator in this application example can be a micro-electro-mechanical system (MEMS) resonator. A MEMS resonator is a component based on the mechanical resonance effect. It is a miniature resonator that integrates micro-sensors, micro-actuators, micro-mechanical structures, signal processing units and control circuits, manufactured based on advanced semiconductor processing technology. It has the advantages of small size, light weight, low power consumption, low price, stable performance and high integration.

[0076] Resonators can include temperature-compensated MEMS and resonant MEMS. Temperature-compensated MEMS can be called temperature-sensitive MEMS resonators, while resonant MEMS can be called temperature-stable MEMS resonators.

[0077] Regarding resonant MEMS, within the operating temperature range, such as -40℃ to 85℃, the output signal needs to be relatively stable. In other words, the output signal should fluctuate little with temperature changes, which requires the resonant MEMS to have low temperature sensitivity.

[0078] Temperature-compensated MEMS can compensate for temperature variations in resonant MEMS. During operation, resonant MEMS inevitably experience fluctuations and instability in their output signal within a specific temperature range. Compensation with temperature-compensated MEMS can stabilize the output signal, thus requiring high temperature sensitivity. For example, in a clock system, a resonant MEMS provides a reference resonant frequency, while a temperature-compensated MEMS senses the temperature and compensates for the corresponding frequency response.

[0079] This can be understood as follows: in a resonator, it is necessary to reduce the temperature sensitivity of the resonant MEMS, while conversely, it is necessary to enhance the temperature sensitivity of the temperature-compensated MEMS.

[0080] This application provides a resonator whose temperature sensitivity can be improved or reduced by adjusting the structural dimensions or the crystal orientation of the resonator's material. This allows for the construction of resonant devices with different temperature sensitivities, enabling applications in resonant MEMS with low temperature sensitivity or in temperature-compensated MEMS with high temperature sensitivity. The resonator can be implemented in the following ways.

[0081] As shown in Figure 1, Figure 1 is a schematic diagram of the structure of a MEMS resonator provided in an embodiment of this application.

[0082] In this example, the resonator includes a substrate 300 and a resonant structure 100 disposed above the substrate 300. The resonant structure 100 is disposed on the substrate 300 via a first support post 200. The resonator may also include a cover 400 disposed on the side of the resonant structure 100 opposite to the substrate 300, and the resonant structure 100 is connected to the cover 400 via a second support post 500. That is, there is a space between the substrate 300 and the cover 400, and the resonant structure 100 is located within this space, so that the resonant structure 100 can vibrate within this space.

[0083] As shown in Figures 2 and 3, Figure 2 is a schematic diagram of the resonant structure 100 of the present application, which also shows how the resonant structure is connected to the substrate 300 through the first support pillar 200. Figure 3 is a partial structural diagram of a resonant structure 100 of the present application.

[0084] In this example, multiple resonant units 101 are included. These multiple resonant units 101 can be arranged in an array. For example, in the examples of Figures 2 and 3, four resonant units 101 are included, and these four resonant units 101 are arranged in a ring array. For example, the multiple resonant units 101 can be arranged symmetrically about a first axis (the X-axis in Figure 3), and the multiple resonant units 101 can also be arranged symmetrically about a second axis (the Y-axis in Figure 3). The first axis (the X-axis in Figure 3) and the second axis (the Y-axis in Figure 3) are perpendicular or nearly perpendicular. For example, the angle between the first axis and the second axis is 89° to 91°, and the first axis and the second axis can be considered to be perpendicular.

[0085] In other embodiments, the MEMS resonator may include two resonant elements, or six resonant elements, or eight resonant elements.

[0086] Each resonant unit 101 has a ring structure, with electrodes disposed on the outer and inner sides of the ring structure. The electrodes and the resonant unit can form a capacitor. For example, in Figures 2 and 3, a first electrode 102 is disposed on the outer side of the ring structure, and a second electrode 103 is disposed on the inner side of the ring structure. The first electrode 102 and the second electrode 103 can drive or detect the vibration of the resonant unit 101, respectively. For example, in a clock system, at a specific frequency, the vibration of the resonant unit is converted into a change in capacitance, thereby transmitting the frequency information to the peripheral circuit, thus playing the role of a "clock".

[0087] The first electrode 102 and the second electrode 103 are respectively disposed at intervals with the resonant unit 101 through gaps, which may or may not be filled with material. For example, the dielectric material filled in the gap may be at least one of HfO2, SiNx, or a composite dielectric material, or, if the gap is not filled with dielectric material, its interior is a vacuum. In some examples, the width of the gap may be approximately 100 nm.

[0088] As shown in Figure 2, when multiple resonant units 101 are included, multiple first electrodes 102 on the outside of the multiple resonant units 101 can be connected together.

[0089] In some examples, as shown in Figure 2, the first electrode 102 or the second electrode 103 can be connected to the substrate 100 through the first support post 200. For example, in the example of Figure 2, each second electrode 103 is connected to the substrate 300 through the first support post 200, and the first electrodes 102 connected together can be connected to the substrate 300 through multiple first support posts 200.

[0090] Referring to Figures 2 and 3, each resonant unit 101 is connected to a connecting rod 104. For example, one end of the connecting rod 104 is connected to the outer ring surface of the ring-shaped resonant unit 101, and the other end is connected to the base 105. For example, the resonant unit 101 and the connecting rod 104 can vibrate within the space between the cover 400 and the substrate 300 shown in Figure 1.

[0091] In some examples, as shown in Figure 2, the base 105, which is connected to multiple connecting rods 104, can be connected to a mass block 106, which is connected to the substrate via a first support post 200. For example, multiple mass blocks 106 can be provided, with one mass block 106 between two adjacent resonant units 101. Each mass block 106 is connected to the substrate via a first support post 200 to maintain the resonant structure formed by the resonant units 101 and the connecting rods 104 in a suspended state.

[0092] Among the selectable materials, the materials of the resonant unit 101, connecting rod 104, base 105 and mass block 106 can be the same, for example, they can be at least one of silicon-based materials (such as polycrystalline silicon, single crystal silicon, SiC, etc.), diamond or III-V group semiconductor materials.

[0093] In some manufacturing processes, the resonant unit 101, connecting rod 104, base 105 and mass block 106 can be made using the same process and can be an integrally formed structure.

[0094] Among the available materials, the first support column 200 or the second support column 500 can be made of silicon dioxide or other materials.

[0095] The cover 400 in this application example may have a finned structure to improve the heat dissipation of the resonator.

[0096] The following describes the possible implementation of the resonant unit 101 in conjunction with the accompanying drawings, and the following description uses one of the resonant units 101 as an example.

[0097] As shown in Figure 4, the resonant unit 101 is a ring structure, which includes an outer ring surface Q1 and an inner ring surface Q2. During vibration, the ring-shaped resonant unit expands or contracts synchronously at various locations.

[0098] The ring structure is symmetrically arranged about the first axis (X-axis as shown in Figure 4) and about the second axis (Y-axis as shown in Figure 4). The first axis is perpendicular or nearly perpendicular to the second axis. For example, the angle between the first axis and the second axis is 89° to 91°, which can be considered as the first axis and the second axis being perpendicular.

[0099] As shown in Figure 4, the dimension of the outer toroidal surface Q1 on the X-axis is A, and the dimension of the outer toroidal surface Q1 on the Y-axis is B. A and B are not equal; for example, in Figure 2, A is greater than B.

[0100] In this embodiment, the first axis (X-axis) passes through the geometric center of the outer toroidal surface Q1, and the second axis (Y-axis) passes through the geometric center of the outer toroidal surface Q1.

[0101] The outer toroidal surface Q1 has a dimension A on the X-axis, which can be understood as follows: As shown in Figure 4, the outer toroidal surface Q1 has opposite boundaries on the X-axis, and the distance between the opposite boundaries is A. The outer toroidal surface Q1 has a dimension B on the Y-axis, which can be understood as follows: As shown in Figure 4, the outer toroidal surface Q1 has opposite boundaries on the Y-axis, and the distance between the opposite boundaries is B. The dimension A of the outer toroidal surface Q1 on the X-axis is greater than the dimension of the outer toroidal surface Q1 on any other axis; the dimension B of the outer toroidal surface Q1 on the Y-axis is less than the dimension of the outer toroidal surface Q1 on any other axis. This can be understood as follows: the first axis is the direction of the major axis of the outer toroidal surface Q1, the second axis is the direction of the minor axis of the outer toroidal surface Q1, and the other arbitrary axes in this application example can be understood as axes other than the first and second axes, which all pass through the geometric center of the outer toroidal surface.

[0102] As shown in Figure 4, the dimension of the inner toroidal surface Q2 on the X-axis is C, and the dimension of the inner toroidal surface Q2 on the Y-axis is D. C and D are not equal; for example, in Figure 4, C is greater than D.

[0103] The inner toroidal surface Q2 has a dimension C on the X-axis, which can be understood as follows: As shown in Figure 4, the inner toroidal surface Q2 has relative boundaries on the X-axis, and the distance between the relative boundaries is C; the inner toroidal surface Q2 has a dimension D on the Y-axis, which can be understood as follows: As shown in Figure 4, the inner toroidal surface Q2 has relative boundaries on the Y-axis, and the distance between the relative boundaries is D.

[0104] In some examples, as shown in Figure 4, the geometric center of the inner torus Q2 coincides with the geometric center of the outer torus Q1; or, in other examples, the geometric center of the inner torus Q2 does not coincide with the geometric center of the outer torus Q1.

[0105] In the resonant unit 101 provided in this application, since the dimension A of the outer ring surface Q1 on the X-axis is not equal to the dimension B on the Y-axis, and the dimension A of the outer ring surface Q1 on the X-axis is greater than the dimension of the outer ring surface Q1 on any other axis; and the dimension B of the outer ring surface Q1 on the Y-axis is less than the dimension of the outer ring surface Q1 on any other axis; that is, the outer ring surface Q1 is a non-equiaxial length structure; in addition, the dimension C of the inner ring surface Q2 on the X-axis is not equal to the dimension D on the Y-axis, that is, the inner ring surface Q2 is also a non-equiaxial length structure.

[0106] Based on the above, it can be understood that the resonant unit of the example in this application adopts the non-equiaxial length of the outer ring surface and the non-equiaxial length of the inner ring surface, which can make full use of the temperature sensitivity difference brought about by the anisotropy of the material of the resonant unit, so as to broaden the temperature sensitivity of the resonator and make the resonator have a wider temperature sensitivity adjustment range.

[0107] For example, by adjusting the dimensions of the outer ring surface Q1 and the inner ring surface Q2 of the resonant unit on the X-axis or Y-axis, or by adjusting the ring width, the symmetry of the resonant unit shape can be changed to match the anisotropy of the resonant unit material, thereby improving or reducing temperature sensitivity. This can be applied to resonant MEMS devices with low temperature sensitivity, or to temperature-compensated MEMS devices with high temperature sensitivity.

[0108] The anisotropic resonant unit material exemplified in this application refers to a material whose physical and chemical properties exhibit different characteristics in different directions. For example, from the perspective of microscopic materials science, the formation of anisotropic materials is due to the directional arrangement of atoms within the crystal. The anisotropy of a crystal means that the periodicity and density of the atomic arrangement are not entirely the same along different directions of the crystal lattice, which leads to different physicochemical properties of the crystal in different directions.

[0109] As shown in Figure 4, the distance between the outer ring surface Q1 and the inner ring surface Q2 on the X-axis is Δa, and the distance between the outer ring surface Q1 and the inner ring surface Q2 on the Y-axis is Δb. Δa and Δb are not equal; for example, in Figure 4, Δa is greater than Δb.

[0110] The ring width of this resonant unit is non-uniform; this non-uniform ring width further increases the difference in length and width, thereby further enhancing the temperature sensitivity caused by the material's anisotropy. Furthermore, during vibration, the amplitudes of the long axis end (which can be considered the first axis) and the short axis end (which can be considered the second axis) differ. By changing the ring width at the long and short axis ends, the relative stiffness between the two ends can be altered, thus adjusting the mode shape and allowing for a larger capacitance change during vibration, further optimizing the resonator's performance.

[0111] Based on the non-equiaxial length of the outer toroidal surface Q1, the non-equiaxial length of the inner toroidal surface Q2, and the non-equiwidth structure of the toroidal width, this application also illustrates several possible shapes.

[0112] As shown in Figure 4, the outer torus Q1 is elliptical and the inner torus Q2 is elliptical.

[0113] As shown in Figure 5, Figure 5 illustrates another structure of the resonant unit 101 provided in an embodiment of this application. In this example, the outer ring surface Q1 is approximately elliptical; for example, the two opposite sides of the outer ring surface Q1 in the X direction are planar, while the inner ring surface Q2 is elliptical.

[0114] As shown in Figure 6, Figure 4 illustrates another structure of the resonant unit 101 provided in an embodiment of this application. In this example, the outer ring surface Q1 is elliptical, and the inner ring surface Q2 is nearly elliptical. For example, the two opposite sides of the inner ring surface Q1 in the X direction are planar.

[0115] As shown in Figure 7, Figure 7 illustrates another structure of the resonant unit 101 provided in an embodiment of this application. In this example, the outer ring surface Q1 is a polygon, and the inner ring surface Q2 is an ellipse.

[0116] As shown in Figure 8, Figure 6 illustrates another structure of the resonant unit 101 according to an embodiment of this application. In this example, the outer ring surface Q1 is elliptical, and the inner ring surface Q2 is polygonal.

[0117] As shown in Figure 9, Figure 7 illustrates another structure of the resonant unit 101 according to an embodiment of this application. In this example, the outer ring surface Q1 is a polygon, and the inner ring surface Q2 is a polygon.

[0118] Figures 4 to 9 above are examples of several resonant unit shapes in this application. Of course, the resonant unit can also be other shapes, which will not be listed here.

[0119] In some examples, when at least one of the outer ring Q1 or the inner ring Q2 is elliptical, the deformation amplitude at the major axis end is greater than that at the minor axis end during the vibration of the elliptical ring. If the width of the major axis end is increased to make its stiffness relatively greater than that at the minor axis end, the amplitude of more of the annular portion between the major and minor axis ends can be made closer to that at the major axis end, thus making the deformation more significant.

[0120] Furthermore, in a resonator, the reciprocal of the resonator's quality factor Q is equal to the sum of the reciprocals of the Q values ​​corresponding to each dissipation mechanism, for example, In micro resonators, the dominant dissipation mechanism is thermoelastic loss. Thermoelastic loss is closely related to the temperature gradient within the resonator; the larger the area encompassed by the high temperature gradient, the lower the irreversible thermoelastic loss. In an elliptical ring design, compared to an angular ring structure, the area occupied by the high temperature gradient is smaller, and the temperature transition is more gradual. Therefore, the thermoelastic loss and the quality factor Q are more thermoelastic, further contributing to improving the overall quality factor Q of the resonator.

[0121] In some examples, the dimensions of both the outer and inner annular surfaces are maximized along the first axis, and minimized along the second axis; and the distance between the outer and inner annular surfaces gradually decreases along the rotation direction from the first axis to the second axis.

[0122] In some resonant units, as shown in Figures 4, 5, and 6, on the X-axis, the outer ring Q1 has the largest dimension A, the inner ring Q2 has the largest dimension C, and the distance Δa between the outer ring Q1 and the inner ring Q2 has the largest dimension Δa. On the Y-axis, the outer ring Q1 has the smallest dimension B, the inner ring Q1 has the smallest dimension D, and the distance Δb between the outer ring Q1 and the inner ring Q2 has the smallest dimension Δb.

[0123] In some resonant units, as shown in Figure 10, which illustrates the structure of another resonant unit 101 according to an embodiment of this application, the outer ring surface Q1 has the largest dimension A and the inner ring surface Q2 has the smallest dimension C on the X-axis, while the distance Δa between the outer ring surface Q1 and the inner ring surface Q2 is the largest. On the Y-axis, the outer ring surface Q1 has the smallest dimension B and the inner ring surface Q1 has the largest dimension D, while the distance Δb between the outer ring surface Q1 and the inner ring surface Q2 is the smallest.

[0124] Alternatively, it can be understood that in the examples of Figures 4 to 6, on the X-axis, the major axis of the outer ring surface Q1 is opposite to the major axis of the inner ring surface Q2, and on the Y-axis, the minor axis of the outer ring surface Q1 is opposite to the minor axis of the inner ring surface Q2; in the example of Figure 10, on the X-axis, the major axis of the outer ring surface Q1 is opposite to the minor axis of the inner ring surface Q2, and the minor axis of the outer ring surface Q1 is opposite to the major axis of the inner ring surface Q2.

[0125] For example, in a temperature-compensated MEMS resonant unit, the structure shown in Figures 4 to 6 can be adopted. This is because, on the X-axis, the major axis of the outer ring Q1 is aligned with the major axis of the inner ring Q2, and on the Y-axis, the minor axis of the outer ring Q1 is aligned with the minor axis of the inner ring Q2. This allows for a greater difference in temperature sensitivity caused by the anisotropy of the resonant unit material, enhancing the temperature sensitivity of the temperature-compensated device, providing timely compensation to the resonant MEMS, and improving the stability of the resonant MEMS output signal.

[0126] For example, in a resonant MEMS resonant unit, the structure shown in Figure 10 can be adopted. In the example, since the major axis of the outer ring Q1 is aligned with the minor axis of the inner ring Q2 on the X-axis, and the minor axis of the outer ring Q1 is aligned with the major axis of the inner ring Q2, the temperature sensitivity difference caused by the anisotropy of the resonant unit material can be weakened, thereby reducing the temperature sensitivity of the temperature compensation device and making the output signal of the resonator more stable.

[0127] For example, in resonant MEMS resonant units, the structures shown in Figures 4 to 6 can also be adopted by selecting resonant unit materials with different anisotropies.

[0128] In some embodiments, the outer ring surface Q1 has the largest dimension A on the X-axis and the smallest dimension B on the Y-axis. The relationship between A and B can be: In some other embodiments, the size C of the inner annular surface Q2 is the largest on the X-axis, and the size D of the inner annular surface Q2 is the smallest on the Y-axis.

[0129] Because the resonator in this application exhibits a vibration breathing mode, characterized by periodic contraction and expansion of the resonant unit relative to the origin, with the geometric center as the origin. And / or, This ensures the periodic contraction or expansion of the resonant unit, achieving the breathing vibration mode.

[0130] in addition, And / or, Furthermore, the anisotropy of the resonant unit material can be fully utilized to construct resonant devices with different temperature sensitivities, such as temperature-sensitive MEMS resonators and temperature-stable MEMS resonators.

[0131] For example, in the case where the MEMS resonator includes a temperature-compensated MEMS resonant unit, or,

[0132] As another example, in the case where the MEMS resonator includes a resonant MEMS resonant element, or,

[0133] In temperature-compensated MEMS, greater sensitivity to temperature changes is required. To improve the temperature sensitivity of this device, it is possible to... or, By using this structure, the temperature sensitivity difference caused by the anisotropy of the resonant unit material in the temperature-compensated MEMS resonant unit can be greater, making it more sensitive to temperature changes. This allows for timely compensation of the resonant MEMS.

[0134] In resonant MEMS, a more sluggish response to temperature changes is required. To reduce the temperature sensitivity of this device, it is possible to make... or, This can be understood as follows: the resonant MEMS resonant unit is more rounded than the temperature-compensated MEMS resonant unit, while the temperature-compensated MEMS resonant unit is more flattened than the resonant MEMS resonant unit. The resonant MEMS resonant unit with this structure can reduce the temperature sensitivity difference caused by the anisotropy of the resonant unit material, thereby reducing the temperature sensitivity of the temperature-compensated device and making the output signal of the temperature-compensated device more stable. For example, when the resonant device is used in a clock system, it can make the output frequency more stable.

[0135] This can be understood as follows: Because temperature-compensated MEMS and resonant MEMS have different requirements for temperature sensitivity, in order to fully utilize the anisotropy of the resonant unit material (see Figures 11 and 12), the resonant MEMS resonant unit can be made more rounded than the temperature-compensated MEMS resonant unit, and the temperature-compensated MEMS resonant unit can be made more flattened than the resonant MEMS resonant unit. (The text then abruptly shifts to a seemingly unrelated topic: "In the temperature-compensated MEMS resonant unit...") It can be greater than that in the resonant MEMS resonant unit. Or, in a temperature-compensated MEMS resonant unit It can be greater than that in the resonant MEMS resonant unit.

[0136] As shown in Figures 11 and 12, the temperature-compensated MEMS resonant unit has a flatter shape compared to the resonant MEMS resonant unit, which can also increase the mode shape area and temperature drift (PPM). The temperature drift in this example can be understood as the frequency drift at different temperatures, that is, temperature sensitivity.

[0137] In the examples above, the outer and inner ring surfaces of the temperature-compensated MEMS resonant unit or resonant MEMS resonant unit can have different dimensional limitations. In other examples, the ring width of different MEMS resonant units can also be limited.

[0138] For example, in a temperature-compensated MEMS resonant unit, the distance Δa between the outer ring surface Q1 and the inner ring surface Q2 is the largest in the X direction, and the distance Δb between the outer ring surface Q1 and the inner ring surface Q2 is the smallest in the Y direction. Furthermore, 0 < Δd / Δb ≤ 5, where Δd = Δa - Δb.

[0139] Since 0 < Δd / Δb ≤ 5 in the temperature-compensated MEMS resonant unit, it can be considered that the temperature-compensated resonator has a larger ring width difference on the first axis and the second axis. This can increase the size difference on the first axis and the second axis, thereby further enhancing the temperature sensitivity difference caused by the anisotropy of the resonant unit material on the first axis and the second axis, and enhancing the temperature sensitivity of the temperature-compensated device. For example, it can be sensitively detected when the operating temperature changes within a small range.

[0140] For example, in a resonant MEMS resonant unit, the distance Δa between the outer ring surface Q1 and the inner ring surface Q2 is the largest on the X-axis, and the distance Δb between the outer ring surface Q1 and the inner ring surface Q2 is the smallest on the Y-axis. Furthermore, 0 < Δd / Δb ≤ 3, where Δd = Δa - Δb.

[0141] In a temperature-compensated MEMS resonant unit, Δd / Δb can be greater than in a resonant MEMS resonant unit. That is, the ratio of the ring width difference in a temperature-compensated MEMS resonant unit is greater than the ratio of the ring width difference in a resonant MEMS resonant unit.

[0142] In addition, when the resonant unit of the ring structure vibrates, the vibration amplitude of the resonant unit on the first axis and the second axis is different. By limiting the ring width difference of the temperature-compensated MEMS resonant unit or the resonant MEMS resonant unit, the relative stiffness between the first axis and the second axis can be changed, the mode shape of the resonant unit can be adjusted, and the capacitance change amplitude of the resonant unit during vibration can be made larger.

[0143] The examples above demonstrate how to adapt a resonant unit to a temperature-compensated MEMS or a resonant MEMS by changing its shape and size. Additionally, the characteristics of the resonant unit material can be altered to broaden its temperature sensitivity. For instance, the resonant unit may include a first material, where the angle between the crystal orientation of the first material and the extension direction of the connecting rod is 0° or 45°.

[0144] For example, as shown in Figure 11, which illustrates a resonator comprising multiple temperature-compensated MEMS resonant units, the angle between the crystal orientation of the first material and the extension direction of the connecting rod in any of the temperature-compensated MEMS resonant units can be 45°. See Figure 9, where the black arrows indicate the crystal orientation of the first material. For example, the first material may include single-crystal silicon, and its crystal orientation can be the silicon 100 crystal orientation.

[0145] In a temperature-compensated MEMS resonant unit, when the angle between the crystal orientation of the first material and the X-direction is 45°, it is beneficial for the temperature compensation device to remain sensitive to temperature drift, so that the temperature compensation device can effectively compensate the resonant MEMS at different temperatures, even if the temperature drift range is very small.

[0146] As another example, as shown in Figure 12, a resonator comprising multiple resonant MEMS resonant units is illustrated. In any resonant MEMS resonant unit, the angle between the crystal orientation of the first material and the extension direction of the connecting rod can be 0°. In Figure 12, the black arrows indicate the crystal orientation of the first material. For example, the first material may include single-crystal silicon, and its crystal orientation can be the silicon 100 crystal orientation.

[0147] In a resonant MEMS resonant unit, when the angle between the crystal orientation of the first material and the extension direction of the connecting rod is 0°, the crystal orientation is conducive to keeping the frequency of the ring structure stable with temperature changes, and will not affect the vibration frequency due to temperature changes.

[0148] As shown in Figures 13 and 14, these figures are schematic diagrams of the connection structure of two types of resonant units 101 and connecting rods 104 provided in the embodiments of this application.

[0149] In the example shown in Figure 13, the outer ring surface Q1 has the largest dimension on the X-axis, the inner ring surface Q2 has the largest dimension on the X-axis, and the inner ring surface Q2 has the smallest dimension on the Y-axis. The connecting rod 104 is connected to the outer ring surface Q1, and the connection point between the connecting rod 104 and the outer ring surface Q1 is on the X-axis. That is, the connecting rod 104 is connected to the long axis end of the outer ring surface Q1.

[0150] In the example shown in Figure 14, the outer ring surface Q1 has the largest dimension on the X-axis, the inner ring surface Q2 has the largest dimension on the X-axis, and the inner ring surface Q2 has the smallest dimension on the Y-axis. The connecting rod 104 is connected to the outer ring surface Q1, and the connection point between the connecting rod 104 and the outer ring surface Q1 is on the Y-axis. That is, the connecting rod 104 is connected to the short axis end of the outer ring surface Q1.

[0151] When the connecting rod 104 is connected to the long axis end of the outer ring surface Q1 or to the short axis end of the outer ring surface Q1, the vibration mode of the resonant unit can be made more symmetrical, thus optimizing the output signal of the resonator. In addition, the temperature-sensitive design of the resonator can also be optimized, for example, when the connecting rod 104 is connected to the long axis end of the outer ring surface Q1.

[0152] Continuing with Figure 13, when the connecting rod 104 is connected to the long axis end of the outer ring surface Q1, the connecting rod 104 extends along the X-axis. Alternatively, in Figure 14, when the connecting rod 104 is connected to the short axis end of the outer ring surface Q1, the connecting rod 104 extends along the Y-axis.

[0153] When the connecting rod 104 extends along the X-axis or along the Y-axis, the mode shape of the resonant unit can be further optimized, making the mode shape more symmetrical.

[0154] In some embodiments, the length of the connecting rod 104 is one-quarter of the resonant wavelength of the MEMS resonator, or close to one-quarter of the resonant wavelength. As shown in Figure 14, the length of the connecting rod 104 can be understood as follows: the connection position between the connecting rod 104 and the outer ring surface Q1 is the first position, the connection position between the connecting rod 104 and the base 105 is the second position, and the distance between the first position and the second position is the length S of the connecting rod 104.

[0155] When the length of the connecting rod 104 is one-quarter or close to one-quarter of the resonant wavelength of the MEMS resonator, the vibration amplitude at the connection between the connecting rod 104 and the base 105 is small. For example, the amplitude at this position can be zero. In this way, the low support loss of the connecting rod can be achieved, so that the MEMS resonator has a higher quality factor Q and improves the working performance of the MEMS resonator.

[0156] In some structures implemented with the connecting rod 104, the connecting rod 104 can be a solid structure, not a hollow structure. A solid connecting rod can also reduce thermoelastic losses, resulting in a higher quality factor Q for the resonator.

[0157] This application does not limit the cross-sectional shape of the connecting rod 104. For example, the cross-section can be rectangular, circular, or elliptical.

[0158] To optimize the mode shape of the resonant unit, the cross-section of the connecting rod 104 can be a symmetrical structure. For example, the cross-section of the connecting rod 104 can be symmetrically arranged about the extension direction of the connecting rod.

[0159] As shown in Figures 13 and 14, the connecting rod 104 includes a connecting portion 104A connected to the outer ring surface Q1 and a suspended portion 104B connected to the connecting portion 104A. The cross-sectional area of ​​the connecting portion 104A is smaller than the cross-sectional area of ​​the suspended portion 104B.

[0160] That is, when the resonant unit vibrates, because the area of ​​the connection between the connecting rod 104 and the resonant unit is small, the vibration loss at that location can be reduced, the support loss of the entire connecting rod can be reduced, thereby improving the quality factor Q of the resonator.

[0161] There are several ways to make the cross-sectional area of ​​the connecting part 104A smaller than the cross-sectional area of ​​the suspended part 104B.

[0162] For example, in Figures 13 and 14, the outer wall surface M of the connecting portion 104A is recessed compared to the outer wall surface M of the suspended portion 104B. This recessed structure can surround the circumference of the connecting rod 104, making the cross-sectional area of ​​the connecting portion 104A smaller than that of the suspended portion 104B. This can be understood as the connection between the connecting rod 104 and the annular structure having an inwardly recessed chamfer. In this example, the cross-sectional area of ​​the suspended portion 104B remains unchanged.

[0163] For example, along the axis from the base 105 to the resonant unit 101, the cross-sectional area of ​​the connecting rod 104 gradually decreases, so that the cross-sectional area of ​​the connecting part 104A is smaller than the cross-sectional area of ​​the suspended part 104B.

[0164] In the description of this specification, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0165] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A MEMS resonator, characterized in that, include: At least one resonant unit; Connecting rod; Any of the resonant units is a ring structure, the ring structure includes an outer ring surface and an inner ring surface, and the connecting rod is connected to the outer ring surface; The outer ring surface has a dimension A on the first axis and a dimension B on the second axis; the dimension A of the outer ring surface on the first axis is greater than the dimension of the outer ring surface on any other axis; the dimension B of the outer ring surface on the second axis is less than the dimension of the outer ring surface on any other axis. The inner annular surface has a dimension C on the first axis and a dimension D on the second axis, where C and D are not equal. On the first axis, the distance between the outer ring surface and the inner ring surface is Δa, and on the second axis, the distance between the outer ring surface and the inner ring surface is Δb, where Δa is greater than Δb. The first axis is perpendicular to the second axis, the annular structure is symmetrically arranged about the first axis, and the annular structure is symmetrically arranged about the second axis.

2. The MEMS resonator according to claim 1, characterized in that, The dimension C of the inner annular surface on the first axis is greater than the dimension of the inner annular surface on any other axis, and the dimension D of the inner annular surface on the second axis is smaller than the dimension of the inner annular surface on any other axis; or... The dimension C of the inner annular surface on the first axis is smaller than the dimension of the inner annular surface on any other axis, and the dimension D of the inner annular surface on the second axis is larger than the dimension of the inner annular surface on any other axis.

3. The MEMS resonator according to claim 1 or 2, characterized in that, The outer annular surface is an ellipse, and / or the inner annular surface is an ellipse.

4. The MEMS resonator according to any one of claims 1-3, characterized in that, The distance Δa between the outer ring surface and the inner ring surface on the first axis is greater than the distance between the outer ring surface and the inner ring surface on any other axis. The distance Δb between the outer annular surface and the inner annular surface on the second axis is less than the distance between the outer annular surface and the inner annular surface on any other axis.

5. The MEMS resonator according to any one of claims 1-4, characterized in that, The resonant unit includes a temperature-compensated MEMS resonant unit and a resonant MEMS resonant unit. The temperature-compensated MEMS resonant unit Greater than the resonant MEMS resonant unit 6. The MEMS resonator according to claim 5, characterized in that, In the temperature-compensated MEMS resonant unit In the resonant MEMS resonant unit 7. The MEMS resonator according to claim 5, characterized in that, The temperature-compensated MEMS resonant unit The resonant MEMS resonant unit.

8. The MEMS resonator according to any one of claims 1-7, characterized in that, The resonant unit includes a temperature-compensated MEMS resonant unit and a resonant MEMS resonant unit. The temperature-compensated MEMS resonant unit Greater than the resonant MEMS resonant unit 9. The MEMS resonator according to claim 8, characterized in that, In the temperature-compensated MEMS resonant unit In the resonant MEMS resonant unit 10. The MEMS resonator according to claim 8, characterized in that, The temperature-compensated MEMS resonant unit The resonant MEMS resonant unit.

11. The MEMS resonator according to any one of claims 1-10, characterized in that, The resonant unit includes a temperature-compensated MEMS resonant unit and a resonant MEMS resonant unit. The temperature-compensated MEMS resonant unit Greater than the resonant MEMS resonant unit Δd is the difference in ring width, Δd=Δa-Δb.

12. The MEMS resonator according to claim 11, characterized in that, The temperature-compensated MEMS resonant unit has a value of 0 < Δd / Δb ≤ 5. The resonant MEMS resonant unit has a value of 0 < Δd / Δb ≤ 3.

13. The MEMS resonator according to any one of claims 1-12, characterized in that, The resonant unit includes a temperature-compensated MEMS resonant unit and a resonant MEMS resonant unit, both of which are silicon. The angle between the crystal orientation of the silicon material in the temperature-compensated MEMS resonant unit and the extension direction of the connecting rod is 45°; or, The angle between the crystal orientation of the silicon material in the resonant MEMS resonant unit and the extension direction of the connecting rod is 0°.

14. The MEMS resonator according to any one of claims 1-13, characterized in that, The connecting rod extends along the first axis, and the connection point between the connecting rod and the outer annular surface is on the first axis; or... The connecting rod extends along the second axis, and the connection position between the connecting rod and the outer ring surface is on the second axis. The dimension C of the inner annular surface on the first axis is greater than the dimension of the inner annular surface on any other axis, and the dimension D of the inner annular surface on the second axis is less than the dimension of the inner annular surface on any other axis.

15. The MEMS resonator according to any one of claims 1-14, characterized in that, The connecting rod includes a connecting portion connected to the outer annular surface and a suspended portion connected to the connecting portion, wherein the cross-sectional area of ​​the connecting portion is smaller than the cross-sectional area of ​​the suspended portion.

16. The MEMS resonator according to claim 15, characterized in that, The outer wall surface of the connecting portion is recessed compared to the outer wall surface of the suspended portion.

17. An electronic device, characterized in that, include: Peripheral circuits; The peripheral circuit is connected to the MEMS resonator as described in any one of claims 1-16.

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