Cantilever resonator

Abstract

The utility model provides a cantilever resonator, 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, metal 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, in particular to a kind of cantilever resonators. BACKGROUND

[0002] Cantilever resonator is a kind of element widely used in micro-electro-mechanical system and nano-electro-mechanical system.For example, cantilever resonator is applied to various sensors, such as pressure sensor, accelerometer, mass sensor, etc.In the field of biological sensing, its high sensitivity can be used to detect the mass change of biological molecules, so as to realize the detection and analysis of specific biological molecules.In communication system, cantilever resonator can also be used as filter and frequency control element to realize high-precision frequency selection.

[0003] In the prior art, cantilever resonator includes a cantilever beam, which deforms under external force, and the natural frequency of the cantilever beam and the applied force or other physical quantity form a resonance frequency, and the applied force or other physical quantity is detected by changing the vibration mode to judge the physical quantity applied by the outside world.

[0004] However, the above-mentioned cantilever resonator has large frequency noise and unstable output, and long-term use, easy to appear cantilever beam fatigue, lead to the change of resonant frequency, and the existing cantilever resonator frequency modulation is more difficult, unable to restore the original frequency, easy to lead to the failure of cantilever resonator. CONTENT OF THE INVENTION

[0005] The present application provides a kind of cantilever resonator, to solve the existing however, above-mentioned cantilever resonator long-term use, easy to appear cantilever beam fatigue, lead to the change of resonant frequency, and the existing cantilever resonator frequency modulation is more difficult, unable to restore the original frequency, easy to lead to the failure of cantilever resonator problem.

[0006] In order to achieve the above-mentioned purpose, the technical scheme of the present application is as follows:

[0007] The present application provides a kind of cantilever resonator, to solve the existing however, above-mentioned cantilever resonator long-term use, easy to appear cantilever beam fatigue, lead to the change of resonant frequency, and the existing cantilever resonator frequency modulation is more difficult, unable to restore the original frequency, easy to lead to the failure of cantilever resonator problem.

[0008] In some possible implementation ways, the present application provides a kind of cantilever resonator, and the metal layer is silver layer.

[0009] In some possible implementation manners, the embodiment of the present application provides a cantilever beam resonator, and the thickness of the metal layer is 0.2-0.4 μm.

[0010] In some possible implementation manners, the embodiment of the present application provides a cantilever beam resonator, and the cantilever beams are at least four, and each two of the cantilever beams are oppositely arranged, and the two cantilever beams on the same side are connected with the same load component.

[0011] In some possible implementation manners, the embodiment of the present application provides a cantilever beam resonator, and the center of the cantilever member and the center of the load component are on the same straight line, and the at least two cantilever beams on the same side and the at least two connecting members on different sides are symmetrically arranged along the straight line.

[0012] In some possible implementation manners, the embodiment of the present application provides a cantilever beam resonator, and the middle part of the cantilever member has a groove.

[0013] In some possible implementation manners, the embodiment of the present application provides a cantilever beam resonator, and the cantilever member is a square body, and the groove is a square groove.

[0014] In some possible implementation manners, the embodiment of the present application provides a cantilever beam resonator, and the length of the cantilever member is 100-150 μm, the thickness of the cantilever member is 1-3 μm, the length of the cantilever beam is 310-330 μm, the width of the cantilever beam is 93-97 μm, the length of the load component is 100-150 μm, and the width of the load component is 50-70 μm.

[0015] In some possible implementation manners, the embodiment of the present application provides a cantilever beam resonator, and the cantilever member and the cantilever beam each comprise, from bottom to top, a substrate, a bottom electrode layer, a piezoelectric layer, a top electrode layer and a metal layer, the top electrode layer is used for inputting a signal, the bottom electrode layer is used for outputting a signal, and the piezoelectric layer is used for transmitting the signal inputted by the top electrode layer to the bottom electrode layer and the metal layer.

[0016] In some possible implementation manners, the embodiment of the present application provides a cantilever beam resonator, and the thickness of the bottom electrode layer and the thickness of the top electrode layer are each 0.1-0.3 μm, and the thickness of the piezoelectric layer is 0.5-1.5 μm.

[0017] This application provides a cantilever beam resonator, comprising a fixed component, a cantilever assembly, a connecting component, and at least two load components. The cantilever assembly includes a cantilever member and at least two cantilever beams, each cantilever beam positioned opposite each other on both sides of the cantilever member. A metal layer is deposited on the surface of both the cantilever member and the cantilever beams. The load components are connected to the cantilever beams. The connecting component includes at least two connectors, each positioned on a different side of the cantilever member. One end of each connector is connected to the cantilever member, and the other end is connected to the fixed component. The metal layer covers the surfaces of the cantilever member and the cantilever beams. By adjusting the metal layer, the resonant frequency can be adjusted to a preset frequency. For example, if the resonant frequency changes due to fatigue, reducing the metal layer increases the frequency, or increasing the metal layer decreases the frequency, thus adjusting the frequency to the preset frequency. This satisfies various frequency tuning requirements, prevents device failure, extends the lifespan of the cantilever beam resonator, and the symmetrical cantilever beams filter noise frequencies, reduce the generation of stray modes, and stabilize the frequency output. Therefore, the cantilever beam resonator in this application embodiment is easy to tune and provides a stable frequency output. Attached Figure Description

[0018] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0019] Figure 1 A schematic diagram of the cantilever beam resonator provided in the embodiments of this application. Figure 1 ;

[0020] Figure 2 A schematic diagram of the cantilever beam resonator provided in the embodiments of this application. Figure 2 ;

[0021] Figure 3 A flowchart illustrating the frequency modulation method for a cantilever beam resonator provided in this application embodiment;

[0022] Figure 4 for Figure 1 The resonant mode diagram at a frequency of 32kHz is obtained for a metal layer of 0.3μm.

[0023] Figure 5 for Figure 1 The resonant mode diagram of the output at a frequency of 1MHz is shown when the metal layer is 0.3μm.

[0024] Explanation of reference numerals in the attached figures:

[0025] 100 - Fixed components;

[0026] 200-Cantilever Assembly;

[0027] 210 - Cantilever component;

[0028] 211-substrate;

[0029] 212 - bottom electrode layer;

[0030] 213 - piezoelectric layer;

[0031] 214 - top electrode layer;

[0032] 215 - metal layer;

[0033] 220 - cantilever beam;

[0034] 300 - connecting assembly;

[0035] 310 - connecting member.

[0036] The specific embodiments of the application have been shown by way of example in the above figures, and will be described in more detail hereafter. These figures and the written description are not to be construed as limiting the scope of the concept of the application in any way, but are merely to illustrate specific embodiments of the application by reference to specific embodiments. DETAILED DESCRIPTION

[0037] The exemplary embodiments will be described in detail herein with reference to the attached drawings. The description of the exemplary embodiments is intended to apply to all alternative embodiments, as would be understood by one skilled in the art. The following description is not intended to be limited to only the described exemplary embodiments. Rather, the scope of the application is to be determined by the claims and their equivalents.

[0038] It should be noted that the terms "upper", "lower", "inner", "outer", and the like, as used herein to describe the orientation or position of the apparatus or components are based on the orientation or position as shown in the drawings, and are merely used for convenience and are not to be construed as indicating or implying relative importance or specific orientation, and therefore should not be understood as limiting the embodiments of the application.

[0039] In addition, it should also be noted that the terms "first", "second", etc. are used only for descriptive purposes and should not be construed as indicating or implying relative importance or an indicated number of technical features, and therefore the features with "first", "second" can explicitly or implicitly include one or more features, and in the description of the application, the meaning of "multiple" is two or more, unless otherwise specifically limited.

[0040] In this application, unless specifically defined otherwise, the terms "mounting", "connecting", "fixing" and the like should be interpreted broadly, for example, can be fixed connection, can also be detachable connection, or integrated; can be mechanical connection, can also be electrical connection or can communicate with each other; can be direct connection, or indirect connection through intermediate medium, can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0041] Cantilever resonator is a kind of element widely used in micro-electro-mechanical system and nano-electro-mechanical system. For example, cantilever resonator is applied to various sensors, such as pressure sensor, accelerometer, mass sensor, etc. In the field of biological sensing, due to its high sensitivity, it can detect the mass change of biological molecules, so as to realize the detection and analysis of specific biological molecules. In communication system, cantilever resonator can also be used as filter and frequency control element to realize high-precision frequency selection.

[0042] In the prior art, cantilever resonator detects the applied force or other physical quantities by the vibration mode change of cantilever under the action of external force. Since the cantilever will deform, its natural frequency and vibration mode will change, and by measuring these changes, the physical quantity applied by the outside world can be judged.

[0043] However, the cantilever resonator is prone to fatigue after long-term use, resulting in a change in resonance frequency. The existing cantilever resonator is difficult to adjust frequency, and cannot restore the original frequency, which easily leads to failure of the cantilever resonator.

[0044] Therefore, the embodiments of the present application provide a cantilever resonator, which comprises a fixing assembly, a cantilever assembly, a connecting assembly and at least two load assemblies. The cantilever assembly comprises a cantilever piece and at least two cantilever beams, each cantilever beam is arranged on the two sides of the cantilever piece, and the surfaces of the cantilever piece and the cantilever beams are provided with metal layers. The load assembly is connected with the cantilever beam in correspondence. The connecting assembly comprises at least two connecting pieces, each connecting piece is arranged on different side of the cantilever piece, one end of the connecting piece is connected with the cantilever piece, and the other end is connected with the fixing assembly. The metal layer covers the surfaces of the cantilever piece and the cantilever beams, and the resonance frequency is adjusted to the preset frequency by adjusting the thickness and shape of the metal layer. For example, when the cantilever resonator causes a change in resonance frequency due to fatigue, the resonance frequency is adjusted to the preset frequency by reducing or thickening the metal layer, so as to avoid device failure and prolong the service life of the cantilever resonator.

[0045] The present application will be described in detail below in conjunction with Figures 1 to 5 and specific embodiments. Figure 1 The structure of the cantilever resonator provided by the embodiments of the present application is shown in Figure 1 ;Figure 2 A schematic diagram of the cantilever beam resonator provided in the embodiments of this application. Figure 2 ; Figure 3 A flowchart illustrating the frequency modulation method for a cantilever beam resonator provided in this application embodiment; Figure 4 for Figure 1 The resonant mode diagram at a frequency of 32kHz is obtained for a metal layer of 0.3μm. Figure 5 for Figure 1 The resonant mode diagram of the output at a frequency of 1MHz is shown when the metal layer is 0.3μm.

[0046] This application provides a cantilever beam resonator, including: a fixed component 100, a cantilever component 200, a connecting component 300, and at least two load components 400; the cantilever component 200 includes a cantilever member 210 and at least two cantilever beams 220, each cantilever beam 220 being disposed opposite to each other on both sides of the cantilever member 210, and both the cantilever member 210 and the cantilever beams 220 having a metal layer on their surfaces, and the load components 400 being connected to the cantilever beams 220 respectively; the connecting component 300 includes at least two connectors 310, each connector 310 being disposed on different sides of the cantilever member 210, one end of the connector 310 being connected to the cantilever member 210, and the other end being connected to the fixed component 100.

[0047] Specifically, the fixing component 100 provides support for the cantilever assembly 200. The fixing component 100 is U-shaped and has a cavity inside. The cantilever assembly 200 is disposed within the cavity and 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 disposed on opposite sides of the cantilever member 210. The cantilever beams 220 are connected to the load assembly 400, and the extension direction of the cantilever beams 220 is perpendicular to the extension direction of the load assembly 400.

[0048] The connecting assembly 300 includes at least two connectors 310, which are spaced apart and disposed inside the fixing assembly 100. One end of each connector 310 is connected to the cantilever member 210, and the other end is connected to the fixing assembly 100. The cantilever assembly 200 is suspended and fixed to the fixing assembly 100 by the connecting assembly 300.

[0049] 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, two connecting members 310 are arranged on opposite sides of the cantilever member 210, the cantilever member 210 and the connecting member 310 are located on the same side, and the extension direction of the cantilever member 210 is the same as the extension direction of the connecting member 310. Alternatively, two connecting members 310 are arranged on opposite sides of the cantilever member 210, the cantilever beam 220 and the connecting member 310 are located on different sides, and the extension direction of the cantilever beam 220 is perpendicular to the extension 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, and can detect changes in the load 400 more accurately and respond more quickly. Moreover, the symmetric structure can filter noise frequencies and reduce the generation of stray modes.

[0050] For example, the load assembly 400 moves under the action of a force or an electrical signal, causing the cantilever beam 220 and the cantilever member 210 to deform and vibrate. The piezoelectric material in the cantilever beam 220 and the cantilever member 210 will produce different vibrations, which match the input signal, causing the entire resonator to vibrate, and finally generating a vibration mode.

[0051] The metal layer covers the surface of the cantilever member 210 and the cantilever beam 220. By adjusting the thickness of the metal layer, the resonant frequency can be adjusted to a preset frequency. For example, when the cantilever beam resonator changes in resonant frequency due to fatigue, the resonant frequency can be adjusted to a preset frequency by reducing or thickening the metal layer, avoiding device failure and prolonging the service life of the cantilever beam resonator.

[0052] The metal layer covers the surface of the cantilever member 210 and the cantilever beam 220. After the manufacturing process is completed, the mass of silver can be increased or decreased by using plasma etching, thereby adjusting the frequency. Plasma etching is a technology used in semiconductor manufacturing and microelectronic processing. By using active particles in the plasma to chemically react with or physically interact with the surface of a solid, the material can be removed or modified. For example, in a vacuum environment, the gas is ionized by applying radio frequency 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 metal layer in the embodiment of the application, and chemically react with or physically collide with the surface silver atoms, thereby removing silver atoms in the metal layer.

[0053] The cantilever member 210 and the cantilever beam 220 each include a piezoelectric layer 213, and a metal layer is located above the piezoelectric layer 213. The piezoelectric material used by the piezoelectric layer 213 can be aluminum nitride (chemical formula: AlN). When subjected to mechanical stress, the piezoelectric material generates a large amount of electric charge, so that the deformation is quickly converted into an electric signal. It can be understood that, as a piezoelectric material, the aluminum nitride can respond to two frequencies. The aluminum nitride thin film can be piezoelectrically responsive through two vibration modes, i.e., a thickness vibration mode and a thickness shear mode. In the thickness vibration mode, the aluminum nitride thin film is stretched and contracted in the thickness direction thereof, and in the thickness shear mode, the surface of the aluminum nitride thin film is sheared and deformed in a direction perpendicular to the thickness direction. The two modes have different natural frequencies, and thus can respond to two different frequencies. Therefore, the aluminum nitride piezoelectric layer can be excited to generate two different vibration modes, each of which responds to a different frequency. For example, the aluminum nitride piezoelectric layer in the embodiment of the present application can generate a 35K frequency and a 1M frequency resonance mode. By changing the thickness and shape of the metal layer, the stress on the piezoelectric material aluminum nitride can be changed.

[0054] In some possible implementations, the embodiment of the present application provides a cantilever beam resonator, and the metal layer 215 is a silver layer.

[0055] The thickness of the silver layer can be 0.2 μm-0.4 μm. For example, the thickness of the metal layer 215 is 0.3 μm, or the thickness of the metal layer 215 is 0.4 μm. By covering the surfaces of the cantilever member 210 and the cantilever beam 220 with the silver layer, the mass of the silver can be increased or decreased by using a plasma etching method after the manufacturing process is completed, so as to adjust the frequency. The plasma etching is a technology in semiconductor manufacturing and microelectronic processing, which removes or modifies materials by using active particles in plasma to chemically react with or physically act on the surface of a solid. For example, in a vacuum environment, a gas is ionized by applying a radio frequency to generate plasma. Active particles in the plasma, such as ions and free radicals, are guided to the surface of the material to be processed, for example, the silver layer in the embodiment of the present application, to chemically react with or physically impact the surface silver atoms, so as to remove the silver atoms in the silver layer.

[0056] In some embodiments, in order to facilitate adjustment of the thickness and shape of the metal layer to adjust the resonance frequency, a reference line is arranged on the metal layer. The reference line includes a first reference line, a second reference line, and a third reference line. The first reference line is arranged along the length direction of the metal layer, the second reference line is arranged along the width direction of the metal layer, and the third reference line is arranged along the thickness direction of the metal layer. The first reference line and the second reference line are perpendicular to each other, and the first reference line and the second reference line are both perpendicular to the third reference line. It can be understood that the area of the metal layer is the same as the area of the cantilever member 210 and the cantilever beam 220.

[0057] In some possible implementation manners, the cantilever beam resonator provided by the embodiments of the present application has a metal layer 215 with a thickness of 0.2 μm to 0.4 μm. For example, the thickness of 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.

[0058] In some embodiments, the cantilever beam resonator provided by the embodiments of the present application has at least four cantilever beams 220, and each two of the cantilever beams 220 are arranged oppositely, and the two cantilever beams 220 on the same side are connected to the same load assembly 400.

[0059] In a specific implementation, the number of the cantilever beams 220 is four, of which two cantilever beams 220 are on the same side of the cantilever member 210 and are connected to the same load assembly 400, and the other two cantilever beams 220 are on the other side of the cantilever member 210 and are connected to the other load assembly 400, and each two of the cantilever beams 220 are arranged oppositely. The two cantilever beams 220 on the same side have a certain gap, and the embodiments of the present application do not limit the size of the gap.

[0060] Of course, the number of the cantilever beams 220 can be six, of which three cantilever beams 220 are on the same side of the cantilever member 210 and are connected to the same load assembly 400, and the other three cantilever beams 220 are on the other side of the cantilever member 210 and are connected to the other load assembly 400. It can be understood that at least two cantilever beams 220 are connected to the same load assembly 400, which can detect changes in the load 400 more accurately and respond more quickly. Moreover, the symmetrical structure of each two of the cantilever beams 220 arranged oppositely can filter noise frequency and reduce the generation of stray modes.

[0061] In some embodiments, the cantilever beam resonator provided by the embodiments of the present application has the center of the cantilever member 210 and the center of the load assembly 400 on the same straight line, and at least two cantilever beams 220 on the same side and at least two connecting members 310 on different sides are symmetrically arranged along the straight line.

[0062] Specifically, the center of the cantilever member 210 and the center of the load assembly 400 are on the same straight line, and the cantilever assembly 200, the fixing assembly 100 and the connecting assembly 300 are symmetrically arranged along the straight line, so that the whole is symmetrical, which can not only filter noise frequency and reduce the generation of stray modes, but also make signal transmission smoother and reduce delay and distortion.

[0063] In some embodiments, the cantilever beam resonator provided by the embodiments of the present application has a groove in the middle of the cantilever member 210.

[0064] The cantilever 210 is a square body, and a groove is arranged on the cantilever 210, the groove is located in the middle of the cantilever 210, the center of the groove coincides with the center of the cantilever 210, and the shape of the groove is not limited in the embodiment of the application. For example, the groove can be a circular groove or a square groove. For example, the length of the side of the cantilever 210 is 100 μm-150 μm.

[0065] The cantilever 210 is a square body, and the groove is a square groove.

[0066] It should be noted that in the cantilever beam resonator in the embodiment of the application, the length of the side of the cantilever 210 is 100 μm-150 μm, the thickness is 1 μm-3 μm, the length of the cantilever beam 220 is 310 μm-330 μm, the width is 93 μm-97 μm, the length of the load assembly 400 is 100 μm-150 μm, and the width is 50 μm-70 μm.

[0067] The length of the side of the cantilever 210 is 100 μm-150 μm, for example, the length of the side of the cantilever 210 is 100 μm. Alternatively, the length of the side of the cantilever 210 is 120 μm, or the length of the side of the cantilever 210 is 125 μm, or the length of the side of the cantilever 210 is 130 μm, or the length of the side of the cantilever 210 is 140 μm, or the length of the side of the cantilever 210 is 150 μm.

[0068] In some embodiments, the cantilever beam resonator provided by the embodiment of the application has a length of 310 μm-330 μm and a width of 93 μm-97 μm. Specifically, the cantilever beam 220 is a cuboid, and the structure size of the cantilever beam 220 is not limited in the embodiment of the application. For example, the length of the cantilever beam 220 is 320 μm, and the width is 95 μm. The thickness can be the same as that of the load assembly 400, for example, 2 μm. Alternatively, the length of the cantilever beam 220 is 310 μm, and the width is 93 μm. Alternatively, the length of the cantilever beam 220 is 330 μm, and the width is 97 μm.

[0069] In addition, the length of the load assembly 400 is 100 μm-150 μm, and the width is 50 μm-70 μm. Specifically, the load assembly 400 is a cuboid, the length of the load assembly 400 is 100 μm, the width is 50 μm, and the thickness is 2 μm. Alternatively, the length of the load assembly 400 is 150 μm, the width is 70 μm, and the thickness is 2 μm. Alternatively, the length of the load assembly 400 is 125 μm, the width is 60 μm, and the thickness is 2 μm.

[0070] In some embodiments, the cantilevered beam resonator provided by the embodiments of the present application includes the cantilever member 210 and the cantilever beam 220, each of which includes, from bottom to top, a substrate 211, a bottom electrode layer 212, a piezoelectric layer 213, a top electrode layer 214, and a metal layer 215. The top electrode layer 214 is configured to input a signal, the bottom electrode layer 212 is configured to output a signal, and the piezoelectric layer 213 is configured to transmit the signal input by the top electrode layer 214 to the bottom electrode layer 212.

[0071] The cantilever member 210 and the cantilever beam 220 include the substrate 211, the bottom electrode layer 212, the piezoelectric layer 213, the top electrode layer 214, and the metal layer 215. The top view of the bottom electrode layer 212 and the top view of 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 attached to the upper surface of the substrate 211, the lower surface of the top electrode layer 214 is attached to the upper surface of the piezoelectric layer 213, and 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 configured to input a signal, the piezoelectric layer 213 is configured to transmit the signal, and the bottom electrode layer 212 is configured to output a signal.

[0072] The embodiments of the present application do not limit the material of the substrate 211. For example, the substrate 211 can be monocrystalline silicon, polycrystalline silicon, or quartz.

[0073] The embodiments of the present application do not limit the material of the bottom electrode layer 212. For example, the material of the bottom electrode layer 212 is molybdenum (chemical formula: Mo), which forms a bottom molybdenum electrode layer and has good conductivity.

[0074] The embodiments of the present application do 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 amount of electric charge when subjected to mechanical stress, thereby rapidly converting its deformation into an electric signal. It can be understood that as a piezoelectric material, aluminum nitride can respond to two frequencies. The aluminum nitride thin film can respond to piezoelectricity through two main vibration modes, namely thickness vibration mode and thickness shear mode. In the thickness vibration mode, the aluminum nitride thin film stretches in the thickness direction, while in the thickness shear mode, the surface of the aluminum nitride thin film shears in a direction perpendicular to the thickness direction. These two modes have different natural frequencies and can therefore respond to two different frequencies. Thus, the aluminum nitride piezoelectric layer can be excited to produce two different vibration modes, each responding to a different frequency. For example, the aluminum nitride piezoelectric layer in the embodiments of the present application can produce a 35K frequency and a 1M frequency resonance mode.

[0075] The specific structure of the top electrode layer 214 is not limited in the embodiments of the present application. For example, the material of the top electrode layer 214 is molybdenum (Mo). The top molybdenum electrode layer is formed of the same material as the bottom electrode layer 212, so that the conductive performance and electrochemical performance of the top electrode layer 214 and the bottom electrode layer 212 are stable and consistent. In addition, the thermal expansion coefficients of the same material are the same, so that the expansion and contraction degrees of the bottom electrode layer and the top electrode layer are the same when the temperature changes, which helps to reduce the stress and deformation caused by the difference in thermal expansion and improve the thermal stability and reliability of the device.

[0076] Specifically, the metal layer 215 can provide an etching basis for the metal layer and avoid damaging the top electrode layer 214. In addition, the metal layer 215 can be used to release the internal stress caused by the difference in thermal expansion coefficient due to different materials.

[0077] Specifically, the thicknesses of the bottom electrode layer 212 and the top electrode layer 214 are the same, so that the conductive performance of the two is consistent. For example, the thicknesses of the bottom electrode layer 212 and the top electrode layer 214 are 0.1 μm, or the thicknesses of the bottom electrode layer 212 and the top electrode layer 214 are 0.2 μm, or the thicknesses of the bottom electrode layer 212 and the top electrode layer 214 are 0.3 μm.

[0078] Specifically, the thicknesses of the bottom electrode layer 212 and the top electrode layer 214 are the same, so that the conductive performance of the two is consistent. For example, the thicknesses of the bottom electrode layer 212 and the top electrode layer 214 are 0.1 μm, or the thicknesses of the bottom electrode layer 212 and the top electrode layer 214 are 0.2 μm, or the thicknesses of the bottom electrode layer 212 and the top electrode layer 214 are 0.3 μm.

[0079] The thickness of the piezoelectric layer 213 is not limited in the embodiments of the present application. For example, the thickness of the aluminum nitride piezoelectric layer is 0.5 μm, or the thickness of the aluminum nitride piezoelectric layer is 1 μm, or the thickness of the aluminum nitride piezoelectric layer is 0.5 μm.

[0080] The thickness of the metal layer 215 is not limited in the embodiments of the present application. For example, the thickness of the silver electrode metal layer 215 is 0.2 μm, or the thickness of the silver electrode metal layer 215 is 0.3 μm, or the thickness of the silver electrode metal layer 215 is 0.4 μm.

[0081] To achieve the adjustment of the metal layer 215, the embodiment of the present application further provides a frequency adjustment method of a cantilever beam resonator, which adopts any one of the cantilever beam resonators described above, and the method comprises the following steps: S100, detecting the frequency of the cantilever beam resonator by using a frequency measuring instrument. Specifically, the frequency measuring instrument is electrically connected with the cantilever beam resonator, the input end of the frequency measuring instrument is connected with the output end of the cantilever beam resonator, a signal generator or physical knocking is used to make the cantilever beam deform and vibrate, the frequency measuring instrument detects the vibration frequency, and the frequency measuring instrument has a network analysis module, which is used to filter and sweep the detected vibration frequency, so as to obtain the frequency of the cantilever beam resonator.

[0082] S200, according to the frequency, reducing or increasing the thickness of the metal layer 215 of the cantilever beam resonator, 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 decrease 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 the cantilever beam to fatigue, so that the resonant frequency changes, and it is necessary to restore the frequency of the cantilever beam resonator to the original frequency, and the original frequency is the preset frequency. Alternatively, due to test requirements, it is necessary to change the frequency of the cantilever beam resonator to meet the test requirements, and the test frequency is the preset frequency.

[0083] The frequency adjustment method of the cantilever beam resonator in the embodiment of the present application is electrically connected with the cantilever beam resonator by using a frequency measuring instrument, so as to detect the frequency of the cantilever beam resonator. When the frequency deviates from the preset frequency, the frequency of the resonator can be adjusted to be high by reducing the thickness of the metal layer 215, and the frequency of the resonator can be adjusted to be low by increasing the thickness of the metal layer 215. By increasing or reducing the thickness of the metal layer 215, the frequency is adjusted to the preset frequency, which can be the original frequency of the cantilever beam resonator or other required frequency, so as to meet various frequency adjustment requirements.

[0084] In a possible implementation manner, the frequency adjustment method provided by the embodiment of the present application comprises the following steps:

[0085] Comparing the frequency and 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:

[0086]

[0087] Wherein, 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, ti The thickness of the metal layer (215) for the i-th layer.

[0088] In a possible implementation, the method for adjusting the frequency of the cantilever resonator provided by the embodiment of the present application reduces or increases the thickness of the metal layer 215, comprising: increasing the thickness of the metal layer 215 by the magnetron sputtering method. Specifically, the magnetron sputtering method is a physical vapor deposition method, which uses a magnetic field to control the ions in the plasma to impact the material to make it sputter on the surface of the cantilever resonator to form a thin film layer. Taking the silver layer as an example, a high voltage electric field is applied to generate plasma, and then a magnetic field is introduced. The ions in the plasma accelerate under the action of the magnetic force and form a beam, and under the control of the magnetic field, the silver material is bombarded, and the atoms on the surface of the silver material are sputtered and deposited on the surface of the cantilever resonator to form a silver layer. The magnetron sputtering method facilitates the control of the direction and range of atom sputtering by the magnetic field, realizes precise control, and improves the sputtering efficiency and the quality of the metal layer 215.

[0089] The thickness of the metal layer 215 is increased by the plasma etching method. The plasma etching method refers to the reaction between active particles in the plasma and the metal layer 215, so as to remove part of the metal atoms in the metal layer 215, and the reaction product evaporates from the metal layer 215, so as to thin the metal layer 215. By adjusting the power and time of the particles by the plasma etching method, the etching rate and depth can be controlled, so that the metal layer 215 can be thinned as needed.

[0090] Other embodiments of the present application will be apparent to those skilled in the art from consideration of the specification and practice of the application disclosed herein. It is intended that the present application cover any and all variations of the application that come within the scope of the claims and their equivalents. It is intended that the specification and examples be considered exemplary only, with the true scope and spirit of the application indicated by the following claims.

[0091] It should be understood that the application is not limited to the precise construction that has been described above and illustrated in the accompanying drawings, and that various modifications and changes can be made by those skilled in the art without departing from the scope of the application. The scope of the application should only be limited by the appended claims.

Claims

1. A cantilever resonator, characterized by, The device comprises 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 piece (210) and at least two cantilever beams (220), each of the cantilever beams (220) is oppositely arranged on two sides of the cantilever piece (210), and the cantilever piece (210) and the cantilever beams (220) are both provided with a metal layer (215), and the load components (400) are connected with the cantilever beams (220) correspondingly. The connecting component (300) comprises at least two connecting pieces (310), each of the connecting pieces (310) is arranged on different sides of the cantilever piece (210), one end of the connecting piece (310) is connected with the cantilever piece (210), and the other end is connected with the fixed component (100).

2. The cantilever resonator of claim 1, wherein, The metal layer (215) is a silver layer.

3. The cantilever resonator of claim 2, wherein, The thickness of the metal layer (215) is 0.2-0.4 μm.

4. The cantilever resonator of claim 1, wherein, The cantilever beams (220) are at least four, each of the cantilever beams (220) is oppositely arranged, and two cantilever beams (220) on the same side are connected with the same load component (400).

5. The cantilever resonator of claim 1, wherein, The center of the cantilever piece (210) and the center of the load component (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 pieces (310) on different sides are also symmetrically arranged along the straight line.

6. The cantilever resonator of claim 5, wherein, The cantilever piece (210) has a groove in the middle.

7. The cantilever resonator of claim 6, wherein, The cantilever piece (210) is a square body, and the groove is a square groove.

8. The cantilever resonator according to any one of claims 2-7, wherein, The side length of the cantilever piece (210) is 100-150 μm, the thickness is 1-3 μm, the length of the cantilever beam (220) is 310-330 μm, the width is 93-97 μm, the length of the load component (400) is 100-150 μm, and the width is 50-70 μm.

9. The cantilever resonator of claim 8, wherein, The cantilever piece (210) and the cantilever beam (220) both comprise, from bottom to top, a substrate (211), a bottom electrode layer (212), a piezoelectric layer (213), a top electrode layer (214) and a metal layer (215), 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 signals inputted by the top electrode layer (214) to the bottom electrode layer (212) for output.

10. The cantilever resonator of claim 9, wherein, The thickness of the bottom electrode layer (212) and the top electrode layer (214) is 0.1-0.3 μm, and the thickness of the piezoelectric layer (213) is 0.5-1.5 μm.

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