Cantilever resonator
By setting crystal components and etching phonon crystal arrays in the root region of the cantilever beam, energy loss is reflected, solving the problem of increased size of cantilever beam resonators. This achieves cantilever beam resonators with high quality factor and small size, expanding their application range.
Patent Information
- Application Number
- CN202423319565.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-31
- Publication Date
- 2026-01-27
- Estimated Expiration
- 2034-12-31
AI Technical Summary
In existing technologies, increasing the length of the cantilever beam to improve the quality factor of the cantilever beam resonator leads to an increase in device size and limits its application.
A crystal assembly is placed at the root region of the cantilever beam. A phonon crystal array is formed by etching and integrated with the cantilever beam to reflect the energy loss during vibration, reduce the stiffness and length of the cantilever beam, and achieve low-frequency operation.
The cantilever beam resonator, which combines high quality factor at low frequencies with small size, expands the application range of the device.
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Figure CN223843753U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of resonator technology, and in particular to a cantilever beam resonator. Background Technology
[0002] With the development of wireless communication technology, the performance requirements for clock devices are becoming increasingly stringent. Traditional quartz crystal resonators have a high quality factor, but their large size makes it difficult to meet the miniaturization needs of electronic components. With the development of micro-electro-mechanical system resonators (MEMS resonators), MEMS resonators have replaced quartz crystal resonators due to their advantages of miniaturization and integrability. However, the lower quality factor of MEMS resonators limits their market applications.
[0003] In existing technologies, in order to improve the quality factor of devices, such as cantilever beam resonators, the stiffness of the device itself affects its quality factor. For low-frequency cantilever beam devices, lower stiffness is required to excite lower-frequency modes. That is, by increasing the length of the cantilever beam, the stiffness is reduced, thereby improving the quality factor.
[0004] However, increasing the length of the cantilever beam increases the device size and power consumption, thus limiting its application. Utility Model Content
[0005] This application provides a cantilever beam resonator to solve the problem that increasing the length of the cantilever beam increases the size of the device, which limits its application in the prior art.
[0006] To achieve the above objectives, the technical solution of this application is as follows:
[0007] This application provides a cantilever beam resonator, including: a cantilever beam assembly and a crystal assembly; the cantilever beam assembly includes a fixing member and a cantilever beam, one end of the cantilever beam is connected to the fixing member, the cantilever beam has a root region, the root region is adjacent to the fixing member; the crystal assembly is disposed in the root region.
[0008] In some possible implementations, the cantilever beam resonator provided in this application embodiment includes a crystal assembly comprising multiple unit cells, each unit cell being arranged at intervals along a first direction and a second direction on the root region, the first direction and the second direction being perpendicular to each other.
[0009] In some possible implementations, the cantilever beam resonator provided in the embodiments of this application has a cell comprising a body and at least two support beams, each support beam being disposed on a different side of the body, and the body having a perforated structure.
[0010] In some possible implementations, the cantilever beam resonator provided in this application embodiment has a hole-like structure including a first through hole and a plurality of second through holes, with the second through holes spaced around the periphery of the first through hole.
[0011] In some possible implementations, the cantilever beam resonator provided in this application embodiment has a first through hole that is circular and a second through hole that is trapezoidal.
[0012] In some possible implementations, the cantilever beam resonator provided in this application embodiment has a body length of 15um to 25um and a width of 15um to 25um.
[0013] In some possible implementations, the cantilever beam resonator provided in this application embodiment has a support beam with a length of 1µm to 3µm and a width of 0.5µm to 1.5µm.
[0014] In some possible implementations, the cantilever beam resonator provided in this application embodiment has a first through-hole radius of 2.5µm to 2.7µm.
[0015] In some possible implementations, the cantilever beam resonator provided in this application embodiment has an upper bottom length of 3.8um to 4.0um, a lower bottom length of 5.2um to 5.4um, and a height of 3.3um to 3.5um for the second through hole.
[0016] In some possible implementations, the cantilever beam resonator provided in this application embodiment includes a substrate, a bottom molybdenum electrode, an aluminum nitride piezoelectric layer, and a top molybdenum electrode arranged sequentially from bottom to top. A third through-hole is etched on the aluminum nitride piezoelectric layer for electrical connection with the bottom molybdenum electrode to output a signal to the substrate. The top molybdenum electrode is used to connect an external conductive plate to input a signal. The fixing member includes a bottom silicon layer, a silicon dioxide sacrificial layer, a substrate, a bottom molybdenum electrode, an aluminum nitride piezoelectric layer, and a top molybdenum electrode arranged sequentially from bottom to top.
[0017] The cantilever beam resonator provided in this application comprises a cantilever beam assembly and a crystal assembly. The cantilever beam assembly includes a fixed member and a cantilever beam, one end of which is connected to the fixed member. The cantilever beam has a root region adjacent to the fixed member. The crystal assembly is disposed within the root region. By placing the crystal assembly on the cantilever beam and etching it into the root region, the crystal assembly and the cantilever beam are integrated into one unit. When the cantilever beam vibrates, the energy lost through point-based vibration can be reflected back through the crystal assembly, reducing energy loss and thus improving the quality factor of the cantilever beam resonator. Furthermore, etching the crystal assembly into the root region reduces the stiffness of the cantilever beam, enabling it to operate at low frequencies with a smaller length and reducing the overall size of the cantilever beam. Therefore, the cantilever beam resonator in this embodiment combines high quality factor at low frequencies with small size, making it widely applicable. 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 This is a schematic diagram of the cantilever beam resonator provided in the embodiments of this application;
[0020] Figure 2 for Figure 1 Sectional view of AA;
[0021] Figure 3 for Figure 1 Sectional view of BB;
[0022] Figure 4 for Figure 1 A schematic diagram of the structure of a unit cell.
[0023] Explanation of reference numerals in the attached figures:
[0024] 100-Cantilever beam assembly;
[0025] 110 - Fastener;
[0026] 120 - Cantilever beam; 121 - Root region;
[0027] 130-substrate;
[0028] 140 - Bottom molybdenum electrode;
[0029] 150-aluminum nitride piezoelectric layer;
[0030] 160 - Top molybdenum electrode;
[0031] 170-Silica sacrificial layer;
[0032] 180-bottom silicon;
[0033] 200-Crystal Components;
[0034] 210 - Unit cell; 211 - Body; 212 - Hole structure; 213 - Supporting beam; 214 - First through hole; 215 - Second through hole.
[0035] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation
[0036] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.
[0037] It should be noted that in the description of the embodiments of this application, the terms "upper", "lower", "inner", "outer" and other terms indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, and are only for the convenience of description, and are not intended to indicate or imply that the device or component must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the embodiments of this application.
[0038] Furthermore, it should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.
[0039] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," and "fixation," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances. First, the relevant concepts or terms involved in this application will be explained.
[0040] MEMS resonators, short for Micro-Electro-Mechanical System resonators, are resonators manufactured using Micro-Electro-Mechanical System (MEMS) technology. They are devices that generate resonant frequencies based on microelectromechanical systems technology and are fundamental components of MEMS oscillators and clock generators. They are widely used in various electronic products involving frequency transmission and reception. They are characterized by their small size, light weight, compatibility with integrated circuit manufacturing processes, and high stability. The main performance parameters of MEMS resonators include resonant frequency and quality factor. The quality factor, represented by the Q value, is a key performance parameter of MEMS resonators. A high Q value can reduce the dynamic impedance of the resonator, decrease the phase noise of the system, and improve the frequency stability of the oscillator.
[0041] Anchor point loss: This refers to the energy loss caused by mechanical vibration at the resonator boundary, where the energy is not completely reflected back. For example, elastic waves or acoustic waves are transmitted from the resonator to the substrate through the support beam. The dissipation of acoustic waves through the support beam reduces the energy stored in the resonator, thus leading to a decrease in the resonator's quality factor.
[0042] The rapid development of modern wireless communication technology has placed increasingly higher demands on the performance and size of clock devices. Traditional quartz crystal resonators have a high quality factor, but their large size makes them increasingly difficult to meet the miniaturization requirements of electronic components. In recent years, with the rapid development of MEMS resonators, their miniaturization and integrability advantages have gradually made them a substitute for quartz crystals. However, compared to quartz crystals, MEMS resonators have a lower quality factor, which limits their market application.
[0043] To improve the quality factor of MEMS resonators, existing technologies employ optimized anchor points. For example, by setting multiple anchor points and placing the anchor rope at the zero-displacement position of the high-order lateral thin-film silicon piezoelectric thin-film resonator, anchor loss is minimized. Compared to a structure where anchor points are evenly distributed at the edge of the resonator, the load quality factor of the resonator is improved by 65%.
[0044] However, in low-frequency devices, such as cantilever beam resonators, there is typically only one anchor point, requiring alternative methods to improve their quality factor. Furthermore, cantilever beam resonators operate in low-frequency modes, and to achieve lower stiffness, their beam length is relatively large, increasing the device size. While increasing the width can reduce the length, this approach increases the connection area between the anchor point and the substrate, thereby increasing anchor point losses.
[0045] In existing technologies, in order to improve the quality factor of a cantilever beam resonator, the stiffness of the device itself affects its quality factor. For low-frequency cantilever beam devices, lower stiffness is required to excite lower-frequency modes. That is, by increasing the length of the cantilever beam, the stiffness is reduced, thereby improving the quality factor. However, increasing the length of the cantilever beam increases the size of the device, which limits its use.
[0046] In view of this, the cantilever beam resonator provided in this application includes: a cantilever beam assembly and a crystal assembly; the cantilever beam assembly includes a fixing member and a cantilever beam, one end of the cantilever beam is connected to the fixing member, the cantilever beam has a root region, and the root region is adjacent to the fixing member; the crystal assembly is disposed in the root region. By disposing the crystal assembly on the cantilever beam and etching the crystal assembly on the root region of the cantilever beam, the crystal assembly and the cantilever beam are integrated into one piece. When the cantilever beam vibrates, the energy lost through the point of contact can be reflected back through the crystal assembly, reducing energy loss and thus improving the quality factor of the cantilever beam resonator. Moreover, etching the crystal assembly in the root region reduces the stiffness of the cantilever beam, enabling it to operate at low frequencies with a smaller length and reducing the size of the cantilever beam. Therefore, the cantilever beam resonator in this application embodiment has both the characteristics of high quality factor and small size under low-frequency operation.
[0047] The following is combined Figures 1 to 4 The present application will be described in detail with reference to specific embodiments. Figure 1 This is a schematic diagram of the cantilever beam resonator provided in the embodiments of this application; Figure 2 for Figure 1 Sectional view of AA; Figure 3 for Figure 1 Sectional view of BB; Figure 4 for Figure 1 A schematic diagram of the structure of a unit cell.
[0048] This application provides a cantilever beam resonator, including: a cantilever beam assembly 100 and a crystal assembly 200; the cantilever beam assembly 100 includes a fixing member 110 and a cantilever beam 120, one end of the cantilever beam 120 is connected to the fixing member 110, the cantilever beam 120 has a root region 121, the root region 121 is adjacent to the fixing member 110; the crystal assembly 200 is disposed in the root region 121.
[0049] The cantilever beam 120 has a first end and a second end. The first end of the cantilever beam 120 is disposed away from the fixing member 110, and the second end of the cantilever beam 120 faces the fixing member 110 and is connected to the fixing member 110. It should be noted that the substrate 130 of the cantilever beam 120 is connected to the substrate 130 of the fixing member 110, and the root region 121 of the cantilever beam 120 is disposed facing the fixing member 110; for example, the root region 121 of the cantilever beam 120 is located at the second end of the cantilever beam 120. In some embodiments, the cantilever beam 120 is elongated.
[0050] The crystal assembly 200 includes a phononic crystal etched into the root region 121 of the cantilever beam 120, integrating the phononic crystal array with the cantilever beam 120. The root region 121 of the cantilever beam 120 is connected to the substrate 130 of the fixing member 110, ensuring that the acoustic waves of the resonator are transmitted to the substrate 130 via a single path. This allows for a reduction in the length of the cantilever beam 120 without increasing its width, while maintaining low-frequency characteristics. By etching the crystal assembly 200 into the root region 121 of the cantilever beam 120, the cantilever beam 120 and the crystal assembly 200 are integrated, reducing the stiffness of the cantilever beam 120 itself and facilitating the excitation of lower-frequency modes. Furthermore, the crystal assembly 200 can reflect energy, reducing energy loss and improving the quality factor of the cantilever beam resonator.
[0051] It should be noted that phononic crystals are usually composed of two or more elastic materials with different elastic coefficients, and have specific acoustic bandgap characteristics. These acoustic bandgap characteristics can block sound waves of a specific frequency band from passing through the phononic crystal, thereby reducing the loss of the anchor point.
[0052] Phononic crystals are two-dimensional phononic crystals. By changing the shape, size, and arrangement of the phononic crystal, sound waves of a specific frequency band can be blocked from passing through the phononic crystal. Through the reflection effect of the phononic crystal, the energy lost during the vibration of the cantilever beam 120 is reflected back, thereby reducing the loss at the anchor point and improving the quality factor of the cantilever beam resonator.
[0053] In some embodiments, the fastener 110 is U-shaped, and the cantilever beam 120 is located in the middle of the fastener 110.
[0054] Understandably, for the cantilever beam 120, the structure's intrinsic frequency is affected by its stiffness. Stiffness depends not only on material properties but also on the structural dimensions. To realize a low-frequency cantilever beam 120 device, it's inevitable to increase the length of the cantilever beam 120, thereby reducing its stiffness. This not only increases the size of the low-frequency device, but the increased device load and surface area also increase energy loss and reduce the quality factor.
[0055] In this embodiment, the cantilever beam resonator is mounted on the cantilever beam 120 via a crystal assembly 200. The crystal assembly 200 is etched into the root region 121 of the cantilever beam 120, integrating the crystal assembly 200 with the cantilever beam 120. When the cantilever beam vibrates, the energy lost through point-based vibration can be reflected back through the crystal assembly 200, reducing energy loss and thus improving the quality factor of the cantilever beam resonator. Furthermore, the etching of the crystal assembly 200 in the root region 121 reduces the stiffness of the cantilever beam 120, enabling it to operate at low frequencies with a smaller length and reducing the overall size of the cantilever beam 120. Therefore, the cantilever beam resonator in this embodiment combines high quality factor and small size for low-frequency operation.
[0056] In some possible implementations, the cantilever beam resonator provided in this application embodiment includes a crystal assembly 200 comprising a plurality of unit cells 210, each unit cell 210 being arranged at intervals along a first direction and a second direction on the root region 121, the first direction and the second direction being perpendicular to each other.
[0057] The crystal assembly 200 includes a two-dimensional phononic crystal array formed by multiple unit cells 210. Each unit cell 210 is periodically arranged on the root region 121 along a first direction and a second direction, which are perpendicular to each other. The first direction is the same as the length direction of the cantilever beam 120, and the second direction is the same as the width direction of the cantilever beam 120.
[0058] In some embodiments, this application does not specifically limit the structure and size of the unit cell 210. For example, the unit cell 210 is a rectangular unit cell 210, composed of a plurality of rectangular unit cells 210 arranged periodically. The body 211 of the rectangular unit cell 210 has a rectangular structure, and the body 211 of the unit cell 210 has etched columnar holes 214 and trapezoidal holes 215. Support beams 213 are provided at the center of each of the four sides of the body 211 of the unit cell 210. In other embodiments, the unit cell 210 may also be a square unit cell 210.
[0059] In some possible implementations, the cantilever beam resonator provided in this application embodiment has a cell 210 including a body 211 and at least two support beams 213, with each support beam 213 disposed on a different side of the body 211, and a hole structure 212 disposed on the body 211.
[0060] In a specific implementation, there are two support beams 213. Each support beam 213 can be set on two adjacent sides of the main body 211, or on two opposite sides of the main body 211. This application embodiment does not impose any restrictions on this.
[0061] In some embodiments, the number of support beams 213 is four, and each support beam 213 is spaced apart around the periphery of the body 211.
[0062] In some possible implementations, the cantilever beam resonator provided in this application embodiment has a hole structure 212 including a first through hole 214 and a plurality of second through holes 215, with the second through holes 215 spaced around the periphery of the first through hole 214.
[0063] In a specific implementation, the first through hole 214 is located in the middle of the body 211, and the second through hole 215 is arranged around the periphery of the first through hole 214. For example, there is one first through hole 214 and four second through holes 215, with each second through hole 215 corresponding to one of the periphery of the body 211.
[0064] In some possible implementations, the cantilever beam resonator provided in this application embodiment has a first through hole 214 that is a circular hole and a second through hole 215 that is a trapezoidal hole.
[0065] In practice, the first through hole 214 is a round hole, and its size and dimensions can be set according to the actual situation. This application does not impose any restrictions on this.
[0066] This application does not limit the number and shape of trapezoidal holes. For example, there are four trapezoidal holes 215. The upper base of the trapezoidal hole 215 faces the cylindrical hole 214, and the lower base of the trapezoidal hole 215 is away from the cylindrical hole 214. The upper base of the trapezoidal hole 215 is less than or equal to the lower base of the trapezoidal hole 215. Each trapezoidal hole 215 is corresponding to the periphery of the body 211 structure of the cell 210, that is, each side corresponds to one trapezoidal hole 215.
[0067] In some possible implementations, the cantilever beam resonator provided in this application embodiment has a body 211 with a length of 15um to 25um and a width of 15um to 25um.
[0068] In some embodiments, the unit cell 210 has an overall length of 20 μm and a width of 20 μm, wherein the support beam 213 has a length of 2 μm and a width of 1 μm, the cylindrical hole 214 has a radius of 2.5 μm to 2.7 μm, and the trapezoidal hole 215 has an upper base length of 3.8 μm to 4.0 μm, a lower base length of 5.2 μm to 5.4 μm, and a height of 3.3 μm to 3.5 μm.
[0069] It should be noted that the cell 210 can achieve isolation of sound waves in different frequency bands by changing the size of the body 211, the cylindrical hole 214 and the four trapezoidal holes 215.
[0070] In some possible implementations, the cantilever beam resonator provided in this application embodiment has a support beam 213 with a length of 1µm to 3µm and a width of 0.5µm to 1.5µm.
[0071] For example, the length of the support beam 213 is 2µm and the width is 1µm, and the length of each support beam 213 is 2µm and the width is 1µm. Alternatively, the dimensions of each support beam 213 can be different. For example, one support beam 213 has a length of 2µm and a width of 1µm, and another support beam has a length of 1µm and a width of 0.5µm.
[0072] In some possible implementations, the cantilever beam resonator provided in this application embodiment has a first through hole 214 with a radius of 2.5um to 2.7um.
[0073] For example, the radius of the first through hole 214 can be 2.5um, 2.6um or 2.7um.
[0074] In some possible implementations, the cantilever beam resonator provided in this application embodiment has an upper bottom length of 3.8um to 4.0um, a lower bottom length of 5.2um to 5.4um, and a height of 3.3um to 3.5um for the second through hole 215.
[0075] For example, the second through hole 215 is a trapezoidal hole with an upper base length of 3.8 μm, a lower base length of 5.2 μm, and a height of 3.3 μm. Alternatively, the trapezoidal hole has an upper base length of 3.9 μm, a lower base length of 5.3 μm, and a height of 3.4 μm. Or, the trapezoidal hole has an upper base length of 4.0 μm, a lower base length of 5.4 μm, and a height of 3.5 μm. The dimensions of each trapezoidal hole can be the same or different, and can be set according to the actual situation. This application embodiment does not limit this.
[0076] In some possible implementations, the cantilever beam resonator provided in this application embodiment includes a substrate 130, a bottom molybdenum electrode 140, an aluminum nitride piezoelectric layer 150, and a top molybdenum electrode 160 arranged sequentially from bottom to top. A third through-hole is etched on the aluminum nitride piezoelectric layer 150 for electrical connection with the bottom molybdenum electrode 140 to output a signal to the substrate 130. The top molybdenum electrode 160 is used to connect an external conductive plate to input a signal. The fixing member 110 includes a bottom silicon layer 180, a silicon dioxide sacrificial layer, a substrate 130, a bottom molybdenum electrode 140, an aluminum nitride piezoelectric layer 150, and a top molybdenum electrode 160 arranged sequentially from bottom to top.
[0077] The cantilever beam 120 includes a substrate 130, a bottom molybdenum electrode 140, an aluminum nitride piezoelectric layer 150, and a top molybdenum electrode 160 arranged sequentially from bottom to top. The substrate 130 is used to etch a two-dimensional phonon crystal array. The aluminum nitride piezoelectric layer 150 is etched with through holes for electrical connection with the bottom molybdenum electrode 140 to output signals to the substrate 130. The top molybdenum electrode 160 is used to connect an external conductive plate to input signals.
[0078] Specifically, an aluminum nitride piezoelectric layer 150 covers the top molybdenum electrode 160, and a bottom molybdenum electrode 140 covers the bottom molybdenum electrode 140. Through-holes are etched on the aluminum nitride piezoelectric layer 150, and the lower edge of the through-holes is electrically connected to the bottom molybdenum electrode 140. This structure consists of a metal electrode, an aluminum nitride piezoelectric layer 150, and a metal electrode. Utilizing the piezoelectric properties of the materials themselves, such as the connection between the metal electrode and the aluminum nitride piezoelectric layer 150, electrical energy is converted into acoustic energy. Sound waves are reflected at the interface between the medium and air, and then converted back into electrical energy through the inverse piezoelectric effect, such as the connection between the aluminum nitride piezoelectric layer 150 and the metal electrode. This allows waves of a specific frequency to pass through, exhibiting good quality and a large bandwidth.
[0079] A substrate 130 is disposed below the bottom molybdenum electrode 140, and the end of the substrate 130 facing the fixture 110 is etched with
[0080] In some embodiments, an aluminum nitride piezoelectric layer 150 can be deposited on the surface of a molybdenum electrode using thin film processing, photolithography, and wet etching processes.
[0081] In addition to the above four-layer structure, the fixing component 110 also includes a silicon oxide sacrificial layer and a bottom silicon 180. That is, from bottom to top, the components are bottom silicon 180, silicon oxide sacrificial layer, substrate 130, bottom molybdenum electrode 140, aluminum nitride piezoelectric layer 150 and top molybdenum electrode 160. The substrate 130, silicon dioxide sacrificial layer 170 and bottom silicon 180 together form a silicon wafer, which serves as the wafer for fabricating the resonator.
[0082] Compared to traditional devices that etch a two-dimensional phononic crystal onto the substrate 130 region, the cantilever beam resonator with integrated crystal component 200 proposed in this application etches the crystal component 200 onto the root region 121 of the cantilever beam 120, integrating the crystal component 200 and the cantilever beam 120 into one unit. The energy lost through the anchor point during vibration of the cantilever beam 120 can be reflected back by the two-dimensional phononic crystal array, improving the quality factor of the cantilever beam resonator. Since lower stiffness is required to excite lower-frequency modes in low-frequency cantilever beam devices, this application reduces stiffness by etching the crystal component 200 onto the root region 121 of the cantilever beam 120 to facilitate the excitation of lower-frequency modes.
[0083] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the utility models disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this application are indicated by the following claims.
[0084] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.
Claims
1. A cantilever beam resonator, characterized in that, include: Cantilever beam assembly (100) and crystal assembly (200); The cantilever beam assembly (100) includes a fastener (110) and a cantilever beam (120), one end of which is connected to the fastener (110), and the cantilever beam (120) has a root region (121) adjacent to the fastener (110). The crystal assembly (200) is disposed within the root region (121).
2. The cantilever beam resonator according to claim 1, characterized in that, The crystal assembly (200) includes a plurality of unit cells (210), each unit cell (210) being arranged at intervals along a first direction and a second direction on the root region (121), the first direction and the second direction being perpendicular to each other.
3. The cantilever beam resonator according to claim 2, characterized in that, The unit cell (210) includes a body (211) and at least two support beams (213), each of the support beams (213) being disposed on different sides of the body (211), and the body (211) being provided with a hole structure (212).
4. The cantilever beam resonator according to claim 3, characterized in that, The perforated structure (212) includes a first through hole (214) and a plurality of second through holes (215), wherein the second through holes (215) are spaced around the periphery of the first through hole (214).
5. The cantilever beam resonator according to claim 4, characterized in that, The first through hole (214) is a round hole, and the second through hole (215) is a trapezoidal hole.
6. The cantilever beam resonator according to any one of claims 3-5, characterized in that, The length of the body (211) is 15um~25um and the width is 15um~25um.
7. The cantilever beam resonator according to any one of claims 3-5, characterized in that, The length of the support beam (213) is 1um to 3um and the width is 0.5um to 1.5um.
8. The cantilever beam resonator according to claim 4, characterized in that, The radius of the first through hole (214) is 2.5um~2.7um.
9. The cantilever beam resonator according to claim 4 or 5, characterized in that, The second through hole (215) has an upper bottom length of 3.8um~4.0um, a lower bottom length of 5.2um~5.4um, and a height of 3.3um~3.5um.
10. The cantilever beam resonator according to any one of claims 1-5, characterized in that, The cantilever beam (120) includes a substrate (130), a bottom molybdenum electrode (140), an aluminum nitride piezoelectric layer (150), and a top molybdenum electrode (160) arranged sequentially from bottom to top. The aluminum nitride piezoelectric layer (150) has through holes etched on it for electrical connection with the bottom molybdenum electrode (140) to output signals to the substrate (130). The top molybdenum electrode (160) is used to connect an external conductive plate to input signals. The fixing member (110) includes a bottom silicon layer (180), a silicon dioxide sacrificial layer, a substrate (130), a bottom molybdenum electrode (140), an aluminum nitride piezoelectric layer (150), and a top molybdenum electrode (160) arranged sequentially from bottom to top.