Cantilever resonator and frequency modulation method thereof

Abstract

The invention provides a cantilever resonator and a frequency modulation method thereof, and relates to the technical field of resonators. The cantilever beam resonator comprises a fixing assembly, a cantilever assembly, a connecting assembly and at least two load assemblies, the cantilever assembly comprises a cantilever part and at least two cantilever beams, the cantilever beams are oppositely arranged on the two sides of the cantilever part, silver layers are arranged on the surfaces of the cantilever part and the cantilever beams, and the load assembly is correspondingly connected with the cantilever beams; the connecting assembly comprises at least two connecting pieces, the connecting pieces are arranged on different sides of the cantilever piece, one end of each connecting piece is connected with the cantilever piece, and the other end of each connecting piece is connected with the fixing assembly. The frequency is increased by reducing the number of the metal layers or increasing the thickness of the metal layers, so that the frequency is adjusted to the preset frequency, various frequency modulation requirements are met, device failure is avoided, the service life of the cantilever beam resonator is prolonged, and the symmetrical cantilever beams can filter noisy point frequency, reduce generation of stray modes and enable frequency output to be stable.

Description

Technical Field

[0001] The present application relates to the technical field of resonators, and in particular to a cantilever beam resonator and a frequency modulation method thereof. Background Art

[0002] Cantilever beam resonator is a kind of component widely used in micro-electromechanical systems and nano-electromechanical systems. For example, cantilever beam resonators are used in various sensors, such as pressure sensors, accelerometers, mass sensors, etc. In the field of biosensing, its high sensitivity can be used to detect the mass change of biomolecules, thereby realizing the detection and analysis of specific biomolecules. In communication systems, cantilever beam resonators can also be used as filters and frequency control elements to achieve high-precision frequency selection.

[0003] In the prior art, a cantilever beam resonator includes a cantilever beam. When an external force is applied, the cantilever beam is deformed. The natural frequency of the cantilever beam and the applied force or other physical quantity form a resonant frequency. The applied force or other physical quantity is detected by the change in the vibration mode, and the physical quantity applied by the outside world is judged.

[0004] However, the above-mentioned cantilever beam resonator has large frequency noise, unstable output, and is prone to cantilever beam fatigue after long-term use, resulting in changes in the resonant frequency. The existing cantilever beam resonator is difficult to modulate and cannot restore the original frequency, which easily leads to failure of the cantilever beam resonator. Summary of the invention

[0005] The present application provides a cantilever beam resonator to solve the problem that the cantilever beam resonator is prone to cantilever beam fatigue after long-term use, resulting in changes in the resonant frequency, and the existing cantilever beam resonator is difficult to modulate the frequency and cannot restore the original frequency, which easily leads to failure of the cantilever beam resonator.

[0006] In order to solve the above problems, the technical solution of this application is as follows:

[0007] In a first aspect, an embodiment of the present application provides a cantilever beam resonator, comprising: a fixed component, a cantilever component, a connecting component and at least two load components; the cantilever component comprises a cantilever member and at least two cantilever beams, each cantilever beam is relatively arranged on two sides of the cantilever member, and the surfaces of the cantilever member and the cantilever beam are both provided with a metal layer, and the load component is correspondingly connected to the cantilever beam; the connecting component comprises at least two connecting members, each connecting member is arranged on different sides of the cantilever member, one end of the connecting member is connected to the cantilever member, and the other end is connected to the fixed component.

[0008] In a possible implementation, in the cantilever beam resonator provided in the embodiment of the present application, the metal layer is a silver layer.

[0009] In a possible implementation, the cantilever beam resonator provided in the embodiment of the present application has at least four cantilever beams, each cantilever beam is arranged opposite to each other in pairs, and the two cantilever beams located on the same side are connected to the same load component.

[0010] In one possible implementation, in the cantilever beam resonator provided in the embodiment of the present application, the center of the cantilever member and the center of the load assembly are on the same straight line, at least two cantilever beams on the same side are symmetrically arranged along the straight line, and at least two connecting members on different sides are also symmetrically arranged along the straight line.

[0011] In a possible implementation, the cantilever beam resonator provided in the embodiment of the present application has a groove in the middle of the cantilever member.

[0012] In one possible implementation, the cantilever beam resonator provided in the embodiment of the present application, the cantilever member and the cantilever beam both include a substrate, a bottom electrode layer, a piezoelectric layer, a top electrode layer and a metal layer arranged in sequence from bottom to top, the top electrode layer is used to input signals, the bottom electrode layer is used to output signals, and the piezoelectric layer is used to transmit the signal input from the top electrode layer to the bottom electrode layer output.

[0013] In one possible implementation, the cantilever beam resonator provided in the embodiment of the present application has a side length of the cantilever member 210 of 100 μm-150 μm and a thickness of 1 μm-3 μm, a length of the cantilever beam 220 of 310 μm-330 μm and a width of 93 μm-97 μm, and a length of the load component 400 of 100 μm-150 μm and a width of 50 μm-70 μm.

[0014] In a second aspect, an embodiment of the present application further provides a frequency modulation method for a cantilever beam resonator, using any of the cantilever beam resonators described above, the method comprising: detecting the frequency of the cantilever beam resonator by means of a frequency measuring instrument; and reducing or increasing the thickness of the metal layer of the cantilever beam resonator according to the frequency so that the frequency reaches a preset frequency.

[0015] In a possible implementation, the frequency modulation method provided in the embodiment of the present application reduces or increases the thickness of the metal layer of the cantilever beam resonator according to the frequency so that the frequency reaches a preset frequency, including:

[0016] Compare the frequency with the preset frequency: When the frequency is greater than or less than the preset frequency, the thickness of the metal layer of the cantilever beam resonator is reduced or increased to satisfy the following relationship:

[0017]

[0018] Where f1 is the preset frequency, f2 is the frequency, w is the width of the resonator, E eff is the equivalent Young's modulus, ρ i is the density of the i-th layer, t i is the thickness of the metal layer of the i-th layer.

[0019] In a possible implementation, the frequency modulation method provided in the embodiment of the present application reduces or increases the thickness of the metal layer of the cantilever beam resonator, including: reducing the thickness of the metal layer by magnetron sputtering; increasing the thickness of the metal layer by plasma etching.

[0020] The embodiment of the present application provides a cantilever beam resonator and a frequency modulation method thereof, by setting a fixed component, a cantilever component, a connecting component and at least two load components; the cantilever component includes a cantilever member and at least two cantilever beams, each cantilever beam is relatively arranged on both sides of the cantilever member, and the surface of the cantilever member and the cantilever beam are both provided with a silver layer, and the load component is connected to the cantilever beam correspondingly; the connecting component includes at least two connecting members, each connecting member is arranged on different sides of the cantilever member, one end of the connecting member is connected to the cantilever member, and the other end is connected to the fixed component. The metal layer covers the surface of the cantilever member and the cantilever beam, and the resonant frequency is adjusted to a preset frequency by adjusting the metal layer. For example, when the resonant frequency of the cantilever beam resonator changes due to fatigue, the frequency is increased by reducing the metal layer, or the frequency is reduced by thickening the metal layer, so that the frequency is adjusted to the preset frequency, so as to meet various frequency modulation requirements, avoid device failure, and extend the service life of the cantilever beam resonator, and the symmetrical cantilever beam can filter the noise frequency, reduce the generation of spurious modes, and stabilize the frequency output. Therefore, the cantilever beam resonator and the frequency modulation method thereof in the embodiment of the present application facilitate frequency modulation and stabilize the frequency output. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0022] Figure 1 A schematic diagram of the structure of the cantilever beam resonator provided in the embodiment of the present application Figure 1 ;

[0023] Figure 2 A schematic diagram of the structure of the cantilever beam resonator provided in the embodiment of the present application Figure 2 ;

[0024] Figure 3 A flow chart of a frequency modulation method for a cantilever beam resonator provided in an embodiment of the present application;

[0025] Figure 4 for Figure 1 The resonant mode diagram of the output frequency of 32kHz with a metal layer of 0.3μm;

[0026] Figure 5 for Figure 1 Resonant mode diagram of the output frequency of 1M when the metal layer is 0.3μm.

[0027] Description of reference numerals:

[0028] 100-fixed component;

[0029] 200-cantilever assembly;

[0030] 210-cantilever member;

[0031] 211-base;

[0032] 212- bottom electrode layer;

[0033] 213- piezoelectric layer;

[0034] 214-top electrode layer;

[0035] 215-metal layer;

[0036] 220-cantilever beam;

[0037] 300-connection components;

[0038] 310-Connector.

[0039] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0040] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0041] It should be noted that in the description of the embodiments of the present application, terms such as "upper", "lower", "inside" and "outside" indicating orientation or positional relationships are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of description, and do not indicate or imply that the device or component must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be understood as a limitation on the embodiments of the present application.

[0042] In addition, it should be noted that the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or suggesting relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of this application, "multiple" means two or more, unless otherwise clearly and specifically defined.

[0043] In this application, unless otherwise clearly specified and limited, the terms "installation", "connection", "fixation" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or mutual communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0044] Cantilever beam resonator is a kind of component widely used in micro-electromechanical systems and nano-electromechanical systems. For example, cantilever beam resonators are used in various sensors, such as pressure sensors, accelerometers, mass sensors, etc. In the field of biosensing, its high sensitivity can be used to detect the mass change of biomolecules, thereby realizing the detection and analysis of specific biomolecules. In communication systems, cantilever beam resonators can also be used as filters and frequency control elements to achieve high-precision frequency selection.

[0045] In the prior art, cantilever beam resonators detect applied force or other physical quantities by changing the vibration mode of the cantilever beam under the action of external force. Since the cantilever beam will deform, its natural frequency and vibration mode will change accordingly. By measuring these changes, the physical quantity applied by the outside world can be determined.

[0046] However, the above-mentioned cantilever beam resonator has only one cantilever beam, which makes its frequency noise large and the output unstable. In addition, after long-term use, the cantilever beam is prone to fatigue, resulting in changes in the resonant frequency. The existing cantilever beam resonator is difficult to modulate and cannot restore the original frequency, which easily leads to failure of the cantilever beam resonator.

[0047] In view of this, an embodiment of the present application provides a cantilever beam resonator, comprising: a fixed component, a cantilever component, a connecting component and at least two load components; the cantilever component comprises a cantilever member and at least two cantilever beams, each cantilever beam is relatively arranged on both sides of the cantilever member, and the surface of the cantilever member and the cantilever beam are both provided with a silver layer, and the load component is connected to the cantilever beam correspondingly; the connecting component comprises at least two connecting members, each connecting member is arranged on different sides of the cantilever member, one end of the connecting member is connected to the cantilever member, and the other end is connected to the fixed component. The silver layer covers the surface of the cantilever member and the cantilever beam, and the resonant frequency is adjusted to a preset frequency by adjusting the thickness and shape of the silver layer. For example, when the resonant frequency of the cantilever beam resonator changes due to fatigue, the resonant frequency is adjusted to a preset frequency by reducing or thickening the silver layer, thereby avoiding device failure and extending the service life of the cantilever beam resonator.

[0048] Combine the following Figures 1 to 5 The present application is described in detail with reference to the accompanying drawings and specific embodiments. Figure 1 A schematic diagram of the structure of the cantilever beam resonator provided in the embodiment of the present application Figure 1 ; Figure 2 A schematic diagram of the structure of the cantilever beam resonator provided in the embodiment of the present application Figure 2 ; Figure 3 A flow chart of a frequency modulation method for a cantilever beam resonator provided in an embodiment of the present application; Figure 4 for Figure 1 The resonant mode diagram of the output frequency of 32kHz with a metal layer of 0.3μm; Figure 5 for Figure 1 Resonant mode diagram of the output frequency of 1M when the metal layer is 0.3μm.

[0049] In a first aspect, an embodiment of the present application provides a cantilever beam resonator, comprising: a fixed component 100, a cantilever component 200, a connecting component 300 and at least two load components 400; the cantilever component 200 comprises a cantilever member 210 and at least two cantilever beams 220, each cantilever beam 220 is relatively arranged on both sides of the cantilever member 210, and the surfaces of the cantilever member 210 and the cantilever beam 220 are both provided with a metal layer 215, and the load component 400 is correspondingly connected to the cantilever beam 220; the connecting component 300 comprises at least two connecting members 310, each connecting member 310 is arranged on different sides of the cantilever member 210, one end of the connecting member 310 is connected to the cantilever member 210, and the other end is connected to the fixed component 100.

[0050] Specifically, the fixing component 100 is used to provide support for the cantilever component 200. The fixing component 100 is in a shape of a Chinese character 'hui', and has a cavity inside. The cantilever component 200 is arranged in the cavity. The cantilever component 200 includes a cantilever member 210 and at least two cantilever beams 220. The cantilever member 210 is suspended in the cavity, and the two cantilever beams 220 are arranged on opposite sides of the cantilever member 210. Among them, the cantilever beam 220 is connected to the load component 400, and the extending direction of the cantilever beam 220 is perpendicular to the extending direction of the load component 400.

[0051] The connecting component 300 includes at least two connecting members 310. The two connecting members 310 are arranged at intervals on the inner side of the fixing component 100. One end of the connecting member 310 is connected to the cantilever member 210, and the other end is connected to the fixing component 100. The cantilever component 200 is suspended and fixed on the fixing component 100 through the connecting component 300.

[0052] It should be noted that the connecting member 310 and the cantilever beam 220 can be located on the same side of the cantilever member 210, or on different sides of the cantilever member 210. For example, the two connecting members 310 are arranged on opposite sides of the cantilever member 210. The cantilever member 210 and the connecting member 310 are on the same side, and the extending direction of the cantilever member 210 is the same as the extending direction of the connecting member 310. Or, the two connecting members 310 are arranged on opposite sides of the cantilever member 210. The cantilever beam 220 and the connecting member 310 are on different sides, and the extending direction of the cantilever beam 220 is perpendicular to the extending direction of the connecting member 310. It should be noted that the two cantilever beams 220 are symmetrically arranged on both sides of the cantilever member 210, which can detect the change of the load 400 more accurately and respond more quickly. Moreover, through the symmetrical structure, the noise frequency can be filtered and the generation of spurious modes can be reduced.

[0053] Exemplarily, the load component 400 moves under the action of force or the action of an electrical signal, causing the cantilever beam 220 and the cantilever member 210 to deform and vibrate. The piezoelectric materials in the cantilever beam 220 and the cantilever member 210 will generate different vibrations. This vibration matches the input signal, causing the entire resonator to vibrate and finally generating a vibration mode.

[0054] The metal layer 215 covers the surfaces of the cantilever member 210 and the cantilever beam 220. By adjusting the thickness of the metal layer 215, the resonance frequency is adjusted to a preset frequency. For example, when the resonance frequency of the cantilever beam resonator changes due to fatigue, by reducing or thickening the metal layer 215, the resonance frequency is adjusted to the preset frequency, avoiding device failure and extending the service life of the cantilever beam resonator.

[0055] The cantilever 210 and the cantilever beam 220 both include a piezoelectric layer 213, and the metal layer 215 is located above the piezoelectric layer 213. The piezoelectric material used in the piezoelectric layer 213 can be aluminum nitride (chemical formula is AlN), which generates a large charge when subjected to mechanical stress, so that its deformation is quickly converted into an electrical signal. It can be understood that aluminum nitride, as a piezoelectric material, can respond to two frequencies, and the aluminum nitride film can respond piezoelectrically through two vibration modes, namely, the thickness vibration mode and the thickness shear mode. In the thickness vibration mode, the aluminum nitride film expands and contracts in the thickness direction, and in the thickness shear mode, the surface of the aluminum nitride film undergoes shear deformation in a direction perpendicular to the thickness direction. These two modes have different natural frequencies and can therefore respond to two different frequencies. As a result, the aluminum nitride piezoelectric layer can be excited to produce two different vibration modes, and each vibration mode responds to a corresponding different frequency.

[0056] For example, when the thickness of the metal layer is 0.3um, resonance modes with frequencies of 32K and 1M can be generated in the thickness vibration mode and thickness shear mode respectively. When the metal layer is 0.2um, resonance modes with frequencies of 35K and 1.5M can be generated in the thickness vibration mode and thickness shear mode to change the thickness and shape of the metal layer 215.

[0057] The metal layer in the embodiment of the present application covers the surface of the cantilever and the cantilever beam, and the resonant frequency is adjusted to the preset frequency by adjusting the metal layer. For example, when the resonant frequency of the cantilever beam resonator changes due to fatigue, the frequency is increased by reducing the metal layer, or the metal layer is thickened to adjust the frequency to the preset frequency, so as to achieve frequency modulation, avoid device failure, and extend the service life of the cantilever beam resonator. The symmetrical cantilever beam can filter the noise frequency, reduce the generation of stray modes, and stabilize the frequency output. Therefore, the cantilever beam resonator and its frequency modulation method in the embodiment of the present application are convenient for frequency modulation and stabilize the frequency output.

[0058] Among them, the cantilever beam resonator provided in the embodiment of the present application, the metal layer is a silver layer. The thickness of the silver layer can be 0.2μm-0.4μm. For example, the metal layer 215 is 0.2μm, the thickness of the metal layer 215 is 0.3μm, or the thickness of the metal layer 215 is 0.4μm. The surface of the cantilever 210 and the cantilever beam 220 is covered with a silver layer. After the manufacturing process is completed, the mass of silver can be increased or decreased by plasma etching to adjust the frequency. Plasma etching is a technology in semiconductor manufacturing and microelectronics processing. It uses active particles in plasma to react chemically or physically with the solid surface to achieve the purpose of removing or modifying materials. For example, in a vacuum environment, by applying radio frequency to ionize the gas to generate plasma, the active particles in the plasma, such as ions and free radicals, are guided to the surface of the material to be processed, such as the silver layer in the embodiment of the present application, and react chemically or physically collide with the surface silver atoms, thereby removing the silver atoms in the silver layer.

[0059] In some embodiments, in order to adjust the thickness and shape of the metal layer 215 to adjust the resonant frequency, a reference line is provided on the metal layer 215, and the reference line includes a first reference line, a second reference line and a third reference line. The first reference line is provided along the length direction of the metal layer 215, the second reference line is provided along the width direction of the metal layer 215, and the third reference line is provided along the thickness direction of the metal layer 215. The first reference line and the second reference line are perpendicular, and the first reference line and the second reference line are both perpendicular to the third reference line. It can be understood that the coverage area of ​​the metal layer 215 is the same as the area of ​​the cantilever 210 and the cantilever beam 220.

[0060] In a possible implementation, the cantilever beam resonator provided in the embodiment of the present application has at least four cantilever beams 220 , and the cantilever beams 220 are arranged opposite to each other in pairs, and the two cantilever beams 220 on the same side are connected to the same load component 400 .

[0061] In a specific implementation, there are four cantilever beams 220, two of which are located on the same side of the cantilever member 210 and are connected to a load assembly 400, and the other two cantilever beams 220 are located on the other side of the cantilever member 210 and are connected to another load assembly 400, and the cantilever beams 220 are arranged opposite to each other in pairs. There is a certain gap between the two cantilever beams 220 located on the same side, and the embodiment of the present application does not limit the size of the gap.

[0062] Of course, the number of cantilever beams 220 can be six, of which three cantilever beams 220 are located on the same side of the cantilever member 210 and are connected to a load component 400, and the other three cantilever beams 220 are located on the other side of the cantilever member 210 and are connected to another load component 400. It can be understood that at least two cantilever beams 220 are connected to the same load component 400, so that the change of the load 400 can be detected more accurately and reacted more quickly. Moreover, the symmetrical structure in which the cantilever beams 220 are arranged opposite to each other can filter the noise frequency and reduce the generation of spurious modes.

[0063] In one possible implementation, in the cantilever beam resonator provided in the embodiment of the present application, the center of the cantilever member 210 and the center of the load assembly 400 are on the same straight line, at least two cantilever beams 220 on the same side are symmetrically arranged along the straight line, and at least two connecting members 310 on different sides are also symmetrically arranged along the straight line.

[0064] Specifically, the center of the cantilever component 210 and the center of the load component 400 are on the same straight line, and the cantilever component 200, the fixing component 100 and the connecting component 300 are symmetrically arranged along the straight line to make the overall symmetry, which can filter the noise frequency and reduce the generation of stray modes, and can also make the signal transmission smoother and reduce delay and distortion.

[0065] In a possible implementation, in the cantilever beam resonator provided in the embodiment of the present application, a groove is provided in the middle of the cantilever member 210 .

[0066] The cantilever 210 is a square body with a groove disposed thereon. The groove is located in the middle of the cantilever 210, and the center of the groove coincides with the center of the cantilever 210. The embodiment of the present application does not limit the shape of the groove. For example, the groove may be a circular groove or a square groove. For example, the side length of the cantilever 210 is 100 μm-150 μm.

[0067] The cantilever member 210 is a square body, and the groove is a square slot.

[0068] In one possible implementation, the cantilever beam resonator provided in the embodiment of the present application, the cantilever member 210 and the cantilever beam 220 both include a substrate 211, a bottom electrode layer 212, a piezoelectric layer 213, a top electrode layer 214 and a metal layer 215 arranged in sequence from bottom to top, the top electrode layer 214 is used for inputting signals, the bottom electrode layer 212 is used for outputting signals, and the piezoelectric layer 213 is used for transmitting the signal input from the top electrode layer 214 to the bottom electrode layer 212 for output.

[0069] The cantilever member 210 and the cantilever beam 220 include a substrate 211, a bottom electrode layer 212, a piezoelectric layer 213, a top electrode layer 214 and a metal layer 215. The top views of the bottom electrode layer 212 and the top electrode layer 214 are the same as the top view of the substrate 211. The bottom electrode layer 212 is located above the substrate 211. The lower surface of the bottom electrode layer 212 is bonded to the upper surface of the substrate 211. The lower surface of the piezoelectric layer 213 is bonded to the upper surface of the bottom electrode layer 212. The upper surface of the piezoelectric layer 213 is bonded to the lower surface of the top electrode layer 214. The bottom electrode layer 212, the piezoelectric layer 213 and the top electrode layer 214 form a sandwich structure. The top electrode layer 214 is used for inputting signals, and the piezoelectric layer 213 is used for transmitting signals, that is, the input signal of the top electrode layer 214 is transmitted to the bottom electrode layer 212. The bottom electrode layer 212 is used for outputting signals.

[0070] The embodiment of the present application does not limit the material of the substrate 211. For example, the substrate 211 may be single crystal silicon, polycrystalline silicon, or quartz.

[0071] The embodiment of the present application does not limit the material of the bottom electrode layer 212. Exemplarily, the material of the bottom electrode layer 212 is molybdenum (chemical formula: Mo), forming a bottom molybdenum electrode layer with good electrical conductivity.

[0072] The present application example does not limit the material of the piezoelectric layer 213. For example, the material of the piezoelectric layer 213 is aluminum nitride (chemical formula: AlN). Aluminum nitride has a high piezoelectric coefficient and can generate a large charge when subjected to mechanical stress, so that its deformation is quickly converted into an electrical signal.

[0073] It can be understood that aluminum nitride, as a piezoelectric material, can respond to two frequencies, and the aluminum nitride film can perform piezoelectric response through two main vibration modes, namely the thickness vibration mode and the thickness shear mode. In the thickness vibration mode, the aluminum nitride film expands and contracts in the thickness direction, and in the thickness shear mode, the surface of the aluminum nitride film undergoes shear deformation in a direction perpendicular to the thickness direction. These two modes have different natural frequencies and can therefore respond to two different frequencies. As a result, the aluminum nitride piezoelectric layer can be excited to produce two different vibration modes, and each vibration mode responds to a corresponding different frequency. For example, the aluminum nitride piezoelectric layer in the embodiment of the present application can produce resonant modes with a frequency of 35K and a frequency of 1M.

[0074] The specific structure of the top electrode layer 214 is not limited in the embodiment of the present application. For example, the material of the top electrode layer 214 is molybdenum (chemical formula: Mo), forming a top molybdenum electrode layer, which is made of the same material as the bottom electrode layer 212, so that the conductivity and electrochemical properties of the top electrode layer 214 and the bottom electrode layer 212 remain stable and consistent. Moreover, the same material has the same thermal expansion coefficient, so when the temperature changes, the bottom electrode layer and the top electrode layer will expand and contract to the same extent, which helps to reduce stress and deformation caused by thermal expansion differences and improve the thermal stability and reliability of the device.

[0075] Specifically, the metal layer 215 can provide an etching basis to avoid damage to the top electrode layer 214 , and can also be used to release the internal stress generated by the difference in thermal expansion coefficients caused by different materials.

[0076] Specifically, the thickness of the bottom electrode layer 212 and the top electrode layer 214 is the same, so that the conductive properties of the two are consistent. For example, the thickness of the bottom electrode layer 212 and the top electrode layer 214 is 0.1 μm, or the thickness of the bottom electrode layer 212 and the top electrode layer 214 is 0.2 μm, or the thickness of the bottom electrode layer 212 and the top electrode layer 214 is 0.3 μm.

[0077] The embodiment of the present application does not limit the thickness of the piezoelectric layer 213. Exemplarily, the piezoelectric layer 213 is an aluminum nitride piezoelectric layer with a thickness of 0.5 μm, or an aluminum nitride piezoelectric layer with a thickness of 1 μm, or an aluminum nitride piezoelectric layer with a thickness of 0.5 μm.

[0078] The embodiment of the present application does not limit the thickness of the metal layer 215 , and a silver layer is disposed on the metal layer 215 . Exemplarily, the metal layer 215 is 0.2 μm, the thickness of the metal layer 215 is 0.3 μm, or the thickness of the metal layer 215 is 0.4 μm.

[0079] In one possible implementation, the cantilever beam resonator provided in the embodiment of the present application has a side length of the cantilever member 210 of 100 μm-150 μm and a thickness of 1 μm-3 μm, a length of the cantilever beam 220 of 310 μm-330 μm and a width of 93 μm-97 μm, and a length of the load component 400 of 100 μm-150 μm and a width of 50 μm-70 μm.

[0080] The side length of the cantilever 210 is 100 μm-150 μm, for example, the side length of the cantilever 210 is 100 μm, or the side length of the cantilever 210 is 120 μm, or the side length of the cantilever 210 is 125 μm, or the side length of the cantilever 210 is 130 μm, or the side length of the cantilever 210 is 140 μm, or the side length of the cantilever 210 is 150 μm.

[0081] In some embodiments, the cantilever beam resonator provided in the embodiment of the present application has a cantilever beam 220 with a length of 310 μm-330 μm and a width of 93 μm-97 μm. Specifically, the cantilever beam 220 is in the shape of a rectangular parallelepiped. The embodiment of the present application does not limit the structural dimensions of the cantilever beam 220. For example, the cantilever beam 220 is 320 μm long and 95 μm wide, and its thickness can be the same as that of the load component 400, such as 2 μm. Alternatively, the cantilever beam 220 is 310 μm long and 93 μm wide, or the cantilever beam 220 is 330 μm long and 97 μm wide.

[0082] In addition, the load component 400 has a length of 100 μm-150 μm and a width of 50 μm-70 μm. Specifically, the load component 400 is in a rectangular parallelepiped shape, and the load component 400 has a length of 100 μm, a width of 50 μm, and a thickness of 2 μm. Alternatively, the load component 400 has a length of 150 μm, a width of 70 μm, and a thickness of 2 μm. Alternatively, the load component 400 has a length of 125 μm, a width of 60 μm, and a thickness of 2 μm.

[0083] In a second aspect, an embodiment of the present application further provides a frequency modulation method for a cantilever beam resonator, using any of the cantilever beam resonators described above, the method comprising: S100 detecting the frequency of the cantilever beam resonator through a frequency measuring instrument. Specifically, the frequency measuring instrument is electrically connected to the cantilever beam resonator, the input end of the frequency measuring instrument is connected to the output end of the cantilever beam resonator, a signal generator or physical tapping is used to cause the cantilever beam to deform and vibrate, the frequency measuring instrument detects the vibration frequency, and the frequency measuring instrument has a network analysis module for filtering and sweeping the detected vibration frequency, thereby obtaining the frequency of the cantilever beam resonator.

[0084] S200 reduces or increases the thickness of the metal layer 215 of the cantilever beam resonator according to the frequency so that the frequency reaches a preset frequency. Specifically, reducing the thickness of the metal layer 215 of the cantilever beam resonator can increase the frequency of the cantilever beam resonator, and increasing the thickness of the metal layer 215 of the cantilever beam resonator can reduce the frequency of the cantilever beam resonator. It should be noted that the preset frequency can be the original frequency of the cantilever beam resonator. For example, long-term use of the cantilever beam resonator causes fatigue of the cantilever beam, causing the resonant frequency to change. It is necessary to restore the frequency of the cantilever beam resonator to the original frequency, which is the preset frequency. Alternatively, due to test requirements, the frequency of the cantilever beam resonator needs to be changed to meet the test requirements, and the test frequency is the preset frequency.

[0085] The frequency modulation method of the cantilever beam resonator in the embodiment of the present application is to electrically connect the cantilever beam resonator through a frequency measuring instrument to detect the frequency of the cantilever beam resonator. When the frequency deviates from the preset frequency, the frequency of the resonator can be increased by reducing the thickness of the metal layer 215, and the frequency of the resonator can be decreased by increasing the thickness of the metal layer 215. The frequency is adjusted to the preset frequency by increasing or decreasing the thickness of the metal layer 215. The preset frequency can be the original frequency of the cantilever beam resonator or other required frequency, which can meet various frequency modulation usage requirements.

[0086] In a possible implementation, the frequency modulation method provided in the embodiment of the present application reduces or increases the thickness of the metal layer 215 of the cantilever beam resonator according to the frequency so that the frequency reaches a preset frequency, including:

[0087] Comparing the frequency with the preset frequency: When the frequency is greater than or less than the preset frequency, the thickness of the metal layer 215 of the cantilever beam resonator is reduced or increased to satisfy the following relationship:

[0088]

[0089] Where f1 is the preset frequency, f2 is the frequency, w is the width of the resonator, E eff is the equivalent Young's modulus, ρ i is the density of the i-th layer, t i is the thickness of the metal layer 215 of the i-th layer.

[0090] In a possible implementation, the frequency modulation method provided in the embodiment of the present application reduces or increases the thickness of the metal layer 215 of the cantilever beam resonator, including: increasing the thickness of the metal layer 215 by magnetron sputtering. Specifically, the magnetron sputtering method is a physical vapor deposition method that uses a magnetic field to control the ions in the plasma to impact the material so that it sputters on the surface of the cantilever beam resonator to form a thin film layer. Taking the metal layer 215 as a silver layer as an example, by applying a high-voltage electric field to generate plasma, and then introducing a magnetic field, the ions in the plasma are accelerated and formed into a beam under the action of the magnetic force, and bombard the silver material under the control of the magnetic field, so that the atoms on the surface of the silver material are sputtered out and deposited on the surface of the cantilever beam resonator to form a silver layer. The magnetron sputtering method is convenient for controlling the direction and range of atomic sputtering through a magnetic field, achieving precise control, and improving the sputtering efficiency and the quality of the metal layer 215.

[0091] The thickness of the metal layer 215 is increased by plasma etching. Plasma etching refers to using active particles in plasma to react with the metal layer 215, thereby removing some metal atoms in the metal layer 215, and the reaction product evaporates from the metal layer 215, making the metal layer 215 thinner. By adjusting the power and time of the particles in the plasma etching method, the etching rate and depth can be controlled, so that the metal layer 215 can be thinned as needed.

[0092] Those skilled in the art will readily appreciate other embodiments of the present application after considering the specification and practicing the invention disclosed herein. The present application is intended to cover any modification, use or adaptation of the present application, which follows the general principles of the present application and includes common knowledge or customary techniques in the art that are not disclosed in the present application. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present application are indicated by the following claims.

[0093] It should be understood that the present application is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A cantilever beam resonator, characterized in that: It comprises: a fixing assembly (100), a cantilever assembly (200), a connecting assembly (300) and at least two load assemblies (400); The cantilever assembly (200) comprises a cantilever member (210) and at least two cantilever beams (220), each of the cantilever beams (220) being arranged on two sides of the cantilever member (210) in a relative manner, a metal layer (215) being arranged on the surface of the cantilever member (210) and the cantilever beams (220), and the load assembly (400) being connected to the cantilever beams (220) in a corresponding manner; The connecting component (300) comprises at least two connecting members (310), each of the connecting members (310) being arranged on a different side of the cantilever member (210), one end of the connecting member (310) being connected to the cantilever member (210), and the other end being connected to the fixing component (100).

2. The cantilever beam resonator according to claim 1, characterized in that The metal layer is a silver layer.

3. The cantilever beam resonator according to claim 1, characterized in that: There are at least four cantilever beams (220), and the cantilever beams (220) are arranged opposite to each other in pairs, and the two cantilever beams (220) located on the same side are connected to the same load assembly (400).

4. The cantilever beam resonator according to claim 2, characterized in that: The center of the cantilever member (210) and the center of the load assembly (400) are on the same straight line, at least two cantilever beams (220) on the same side are symmetrically arranged along the straight line, and at least two connecting members (310) on different sides are also symmetrically arranged along the straight line.

5. The cantilever beam resonator according to claim 3, characterized in that: The cantilever member (210) has a groove in the middle.

6. The cantilever beam resonator according to any one of claims 2 to 5, characterized in that: The cantilever member (210) and the cantilever beam (220) both include a substrate (211), a bottom electrode layer (212), a piezoelectric layer (213), a top electrode layer (214), and a metal layer (215) arranged in sequence from bottom to top, wherein the top electrode layer (214) is used for inputting signals, the bottom electrode layer (215) is used for outputting signals, and the piezoelectric layer (213) is used for transmitting the signal input by the top electrode layer (214) to the bottom electrode layer (215) for output.

7. The cantilever beam resonator according to any one of claims 2 to 5, characterized in that: The cantilever member (210) has a side length of 100 μm-150 μm and a thickness of 1 μm-3 μm, the cantilever beam (220) has a length of 310 μm-330 μm and a width of 93 μm-97 μm, and the load component (400) has a length of 100 μm-150 μm and a width of 50 μm-70 μm.

8. A frequency modulation method for a cantilever beam resonator, characterized in that: Using the cantilever beam resonator according to any one of claims 1 to 7, the method comprises: Detecting the frequency of the cantilever beam resonator by a frequency measuring instrument; According to the frequency, the thickness of the metal layer (215) of the cantilever beam resonator is reduced or increased so that the frequency reaches a preset frequency.

9. The frequency modulation method of the cantilever beam resonator according to claim 8, characterized in that: The step of reducing or increasing the thickness of the metal layer (215) of the cantilever beam resonator according to the frequency so as to make the frequency reach a preset frequency comprises: Comparing the frequency with the preset frequency: when the frequency is greater than or less than the preset frequency, the thickness of the metal layer (215) of the cantilever beam resonator that is reduced or increased satisfies the following relationship: Where f1 is the preset frequency, f2 is the frequency, w is the width of the resonator, E eff is the equivalent Young's modulus, ρ i is the density of the i-th layer, t i is the thickness of the metal layer (215) of the i-th layer.

10. The frequency modulation method of the cantilever beam resonator according to claim 8, characterized in that: The reducing or increasing the thickness of the metal layer (215) of the cantilever beam resonator comprises: Increasing the thickness of the metal layer (215) by magnetron sputtering; The thickness of the metal layer (216) is reduced by plasma etching.

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