Piezoelectric resonator with high Q value and preparation method

Abstract

The invention relates to a piezoelectric resonator with a high Q value and a preparation method thereof. The resonator comprises: a resonance base; the resonance body unit is cylindrical and is suspended in the resonance base, the resonance body unit is adaptively connected with the resonance base through the supporting beam unit, the resonance body unit comprises a resonance main body and a main body supporting body used for supporting the resonance main body, and the resonance body unit is adaptively connected with the supporting beam unit through the main body supporting body; the resonance main body can vibrate on the main body supporting body; the resonance main body comprises a resonance electrode unit and a piezoelectric layer. The piezoelectric resonator can effectively improve the excitation efficiency of the electric field, effectively suppress the parasitic mode, reduce the loss of the anchor point, and improve the quality factor of the piezoelectric resonator.

Description

Technical Field

[0001] This invention relates to a resonator and its fabrication method, and more particularly to a high-Q piezoelectric resonator and its fabrication method. Background Technology

[0002] With the rapid development of 5G / 6G communication, radio frequency front-end and high-precision sensing technologies, piezoelectric MEMS resonators are increasingly widely used in clock sources, filters and sensors due to their advantages of high frequency stability, small size and easy integration.

[0003] However, traditional piezoelectric resonators have significant performance bottlenecks, mainly including: 1) Uneven electric field distribution: It is difficult to accurately match the strain distribution of the resonant mode, resulting in low electromechanical conversion efficiency and easy excitation of non-target parasitic modes.

[0004] 2) Severe energy leakage at anchor points: Vibration energy is easily dissipated to the substrate through the support anchor points, causing significant mechanical losses and severely limiting the quality factor (Q value) of the resonator.

[0005] Although existing studies have attempted to improve performance by optimizing anchor structure (such as buffer design) or adding modal decoupling design, existing piezoelectric resonators generally still have problems such as low electric field excitation efficiency, severe parasitic modes, and large anchor point losses, making it difficult to meet the application requirements of high-performance piezoelectric resonators. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a high-Q piezoelectric resonator and its fabrication method, which can effectively improve the electric field excitation efficiency, effectively suppress parasitic modes, reduce anchor point loss, and improve the quality factor of the piezoelectric resonator.

[0007] According to the technical solution provided by the present invention, a high-Q piezoelectric resonator is provided, the piezoelectric resonator comprising: Resonant base; The resonant element unit, cylindrical in shape and suspended within the resonant base, is connected to the resonant base via supporting beam units. The resonator unit includes a resonator body and a main support body for supporting the resonator body, and is adapted to be connected to the support beam unit through the main support body, and the resonator body can vibrate on the main support body. The resonant body includes a resonant electrode unit and a piezoelectric layer. The resonant electrode unit includes two resonant electrode layers, and the piezoelectric layer corresponds to the two resonant electrode layers in the resonant electrode unit. One resonant electrode layer is used as the bottom resonant electrode, and the other resonant electrode layer is used as the top resonant electrode. The bottom resonant electrode is located on the main support body. For any resonant electrode layer, the resonant electrode layer includes two resonant electrode sheet groups, each resonant electrode sheet group includes several resonant electrode sheets, each resonant electrode sheet is fan-shaped, and the resonant electrode sheets in the resonant electrode layer are arranged circumferentially along the ring resonator unit, so as to configure the resonant electrode sheets in the resonant electrode layer to form a ring.

[0008] The support beam unit provides axial support to the resonator unit, and the support beam unit includes at least two support beams. The support beam is suspended within the resonant base. One end of the support beam is adapted to the resonant base, and the other end of the support beam is connected to the main support of the resonant unit. The contact connection between the support beam and the main support is located near the displacement node of the vibration mode of the resonant unit. This connection between the support beam and the main support forms a double-beam support structure to improve the stability of the resonant unit.

[0009] A resonator hole is provided within the resonator unit, wherein... The resonator hole penetrates the resonator body and the main support body; The resonant electrode plates are symmetrically arranged on the outer ring of the resonant body hole, and the width of the resonant electrode plates gradually increases along the direction from the center of the resonant body hole to the outer edge of the resonant body unit. The outer edge of the resonant electrode is adjacent to the outer edge of the resonant element, and the inner edge of the resonant electrode is adjacent to the resonant hole.

[0010] For each resonant electrode layer, the number of resonant electrode sheets in each resonant electrode sheet group is consistent, and the two resonant electrode sheet groups are centrally symmetrically distributed. The distribution of the resonant electrode sheets within the resonant electrode layer is aligned with the strain antinode region of the target vibration mode of the resonant body unit to maximize electromechanical conversion efficiency and suppress non-target modes.

[0011] Based on the target vibration mode of the resonant body unit, the electrical connection state between the resonant electrode plates within each resonant electrode layer is configured, wherein... When two adjacent resonant electrode plates are electrically connected, a narrow metal connecting beam is provided between the resonant electrode plates. The two ends of the narrow metal connecting beam are in contact with and electrically connected to the resonant electrode plates on both sides, and the width of the narrow metal connecting beam is much smaller than the fan-shaped length of the resonant electrode plates.

[0012] Within each resonant electrode layer, anchor point loss mitigation openings are configured to avoid the stress belly position of the target vibration mode. The anchor point loss mitigation opening is funnel-shaped, and the opening gradually increases in size along the direction from the center of the resonant body to the edge of the resonant unit. Within the resonant electrode layer, the resonant electrode sheets located on both sides of the anchor point loss mitigation opening are in a non-contact electrical connection state through the anchor point loss mitigation opening.

[0013] When the support beam unit includes two support beams, the two support beams are coaxially symmetrically distributed, and one support beam corresponds to the opening direction of the anchor point loss mitigation opening.

[0014] Within each resonant electrode layer, the angle of the resonant electrode sheet is 30° to 80°.

[0015] A method for fabricating a high-Q piezoelectric resonator, used to fabricate the aforementioned piezoelectric resonator, the method comprising: A resonant substrate is provided, wherein the resonant substrate includes a substrate bottom layer, a sacrificial layer disposed on the substrate bottom layer, and a substrate top layer disposed on the sacrificial layer; A bottom electrode film is prepared on the top layer of the substrate, and the bottom electrode film is patterned to form a resonant bottom electrode after patterning. A piezoelectric base layer and a top electrode film are sequentially prepared on the above-mentioned resonant bottom electrode. Then, the top electrode film is patterned to form a resonant top electrode after patterning. The piezoelectric base layer and the top layer of the substrate are patterned sequentially to form a piezoelectric layer after the piezoelectric base layer is patterned, and at least the main support body and the support beam unit are formed after the top layer of the substrate is patterned, and a sacrifice release window for releasing the sacrifice layer is formed. The sacrificial layer is released using the sacrificial release window formed above, so as to form a suspended resonator unit and a supporting beam unit.

[0016] Before preparing the bottom electrode film, a seed layer is prepared on the top layer of the substrate, and then the bottom electrode film is prepared on the seed layer. When patterning the piezoelectric substrate, the corresponding seed layer is etched and removed simultaneously with the etching of the piezoelectric substrate. Furthermore, after patterning the piezoelectric substrate and the top layer of the substrate, a resonator hole that penetrates the resonator unit is also formed.

[0017] Advantages of this invention: The support beam and the main support body are adapted to each other, and the contact connection between the support beam and the main support body is located near the displacement node of the vibration mode of the resonator unit. The connection between the support beam and the main support body forms a double-beam support structure to improve the stability of the resonator body. The double-beam support structure can achieve stable support for the resonator body and constraint of the target vibration mode, ensuring that the piezoelectric resonator works in a relatively stable mechanical environment and providing stable structural conditions for the excitation of the target vibration mode. In addition, it can also suppress non-target modes, so that when an electric field is applied, the energy is more concentrated for the excitation of the target vibration mode.

[0018] The resonant electrode unit comprises two resonant electrode layers, each containing several resonant electrode plates in a fan shape. This shape alters the electric field distribution around the piezoelectric layer. Simultaneously, the fan-shaped shape results in a more uniform electric field distribution on the cylindrical resonant unit, better matching the vibration mode of the target vibration mode. Furthermore, the electric field of the fan-shaped resonant electrode plates can better excite the tangential vibration of the cylindrical resonant unit, enabling more efficient conversion of electric field energy into the mechanical energy of the target vibration mode and improving mode excitation efficiency.

[0019] Furthermore, the double-beam support structure ring ensures the stability of the resonant body's mechanical structure, allowing the electric field generated by the resonant electrode to fully act on the resonant body, thereby enabling more precise and efficient excitation of the target vibration modes, thus significantly improving the efficiency and quality of mode excitation.

[0020] The double-beam support structure enhances the stability of the resonant core, reduces additional mechanical vibrations caused by external disturbances, and minimizes unnecessary energy exchange between the resonant core and its surrounding environment, thus reducing mechanical losses. Reduced mechanical losses mean that the energy stored in the resonant core is less likely to dissipate, increasing the ratio of stored energy to dissipated energy, which lays the foundation for improved Q-value. When the resonant electrode plates are fan-shaped, the resulting electric field distribution is optimized, reducing ineffective energy dissipation during transmission and conversion, and further reducing electrical losses, thus contributing to improved Q-value.

[0021] By adjusting the dimensions, shape, and other parameters of the double-beam support structure, the resonant frequency of the resonant element within the resonant base can be adjusted. This provides a basis for adapting to the frequency requirements of different application scenarios, enabling the piezoelectric resonator to operate within a suitable frequency range.

[0022] Based on the sector-shaped resonant electrode, the electrical boundary conditions of the piezoelectric resonator can be changed, thereby affecting the target vibration mode of the resonator. The coupling between the electric field generated by the resonant electrode and the target vibration mode can be made tighter, making it easier for the piezoelectric resonator to excite the target mode and achieve better vibration mode matching. This enables precise control of the frequency characteristics of the piezoelectric resonator, allowing the operating frequency of the piezoelectric resonator to be adjusted to the target value more accurately. Furthermore, it enables the target vibration mode to have a higher quality factor and more stable performance at the target operating frequency, meeting the needs of high-precision applications.

[0023] Piezoelectric resonators achieve high Q values ​​while maintaining good electromechanical coupling coefficients, which is beneficial for building high-performance, low-insertion-loss filters and low-phase-noise oscillators.

[0024] Piezoelectric resonators are based on mature SOI substrates and thin film stacking processes. They can be manufactured using standard photolithography, sputtering, RIE etching, and sacrificial layer release techniques without the need for additional complex process steps. This makes manufacturing costs controllable and easy to achieve mass production.

[0025] The narrow metal connecting beam design helps to balance the stress on the resonant electrode sheets, improves the overall mechanical stability and structural consistency of the resonant electrode layer, and enhances the structural stability of the piezoelectric resonator. Piezoelectric resonators are small in size (on the order of 1 mm) and possess excellent shock resistance, disturbance rejection, and stability, making them ideal for applications with stringent requirements for frequency stability and size, such as 5G / 6G RF front-end filters, reference clock oscillators, and high-precision inertial sensors (e.g., gyroscopes). Attached Figure Description

[0026] Figure 1 This is a schematic diagram of one embodiment of the piezoelectric resonator of the present invention.

[0027] Figure 2 This is a schematic diagram of one embodiment of the resonator unit of the present invention.

[0028] Figure 3 For the purposes of this invention Figure 1 The diagram shows a simulation result of an embodiment of modal simulation of a piezoelectric resonator.

[0029] Figure 4 This is a schematic diagram of an embodiment for testing the admittance curve of the piezoelectric resonator of the present invention.

[0030] Explanation of reference numerals in the attached figures: 1-Top layer silicon, 2-Resonator unit, 3-Base bottom electrode ring, 4-Base piezoelectric ring, 5-Support beam, 6-Base suspended groove, 7-Main support body, 8-Resonant bottom electrode, 9-Piezoelectric layer, 10-Bottom electrode lead-out film, 11-Bottom electrode ring window, 13-Piezoelectric lead-out, 14-Resonant top electrode, 15-Resonant electrode sheet, 16-Top electrode lead-out, 17-Top electrode connection end, 18-Resonator hole, 19-Anchor point loss mitigation opening, 20-Inter-chip isolation hole, 21-Narrow metal connecting beam. Detailed Implementation

[0031] The present invention will be further described below with reference to specific accompanying drawings and embodiments.

[0032] To effectively improve the electric field excitation efficiency, effectively suppress parasitic modes, and improve the quality factor of the piezoelectric resonator, this invention provides a high-Q piezoelectric resonator. Specifically, the piezoelectric resonator includes: Resonant base; The resonator unit 2 is cylindrical and suspended within the resonant base. The resonator unit 2 is connected to the resonant base via a supporting beam unit, and it can vibrate within the resonant base. The resonator unit 2 includes a resonator body and a main support body 7 for supporting the resonator body, and is adapted to be connected to the support beam unit through the main support body 7. The resonant body includes a resonant electrode unit and a piezoelectric layer 9. The resonant electrode unit includes two resonant electrode layers. The piezoelectric layer 9 corresponds to the two resonant electrode layers in the resonant electrode unit. One resonant electrode layer is used as the resonant bottom electrode 8, and the other resonant electrode layer is used as the resonant top electrode 14. The resonant bottom electrode 8 is located on the main support body 7. For any resonant electrode layer, the resonant electrode layer includes two resonant electrode sheet groups, each resonant electrode sheet group includes several resonant electrode sheets 15, each resonant electrode sheet 15 is fan-shaped, and the resonant electrode sheets 15 in the resonant electrode layer are arranged along the circumference of the ring resonator unit 2, so as to configure the resonant electrode sheets 15 in the resonant electrode layer to form a ring.

[0033] It should be noted that the piezoelectric resonator of this invention specifically refers to a resonator that primarily operates in a piezoelectric driven mode. Furthermore, when external mechanical disturbances exist, the piezoelectric resonator can detect the charge generated by the external disturbances, thereby enabling the detection of external mechanical disturbances. The piezoelectric resonator of this invention generally includes a resonant base. Figure 1 The figure shows an embodiment of the resonant base of the present invention. As can be seen from the figure, the resonant base can be in the shape of a square ring, and the resonant element 2 is suspended inside the resonant base. Figure 1 In the resonant base, there are a top silicon layer 1, a base bottom electrode ring 3 disposed on the top silicon layer 1, and a base piezoelectric ring 4 disposed on the base bottom electrode ring 3. The specific details of the resonant base will be described below.

[0034] Depend on Figure 1 As can be seen, the resonator unit 2 of the present invention is cylindrical, and the resonator unit 2 is the functional unit of the piezoelectric resonator. The resonator unit 2 is connected to the resonator base through the support beam unit, so that the resonator unit 2 can be supported and assembled in the resonator base through the support beam unit. The support beam unit and the situation of the support beam unit and the resonator base are adapted to be connected will be described in detail below. Please refer to the corresponding description below for details.

[0035] Generally, the resonant unit 2 may include a resonant body and a main support 7. The resonant body is the functional unit of the resonant unit 2. When the resonant body is projected onto the main support 7, it is at least circular. The main support 7 supports the resonant body, meaning the resonant body is fabricated on the main support 7. Generally, the resonant body and the main support 7 can vibrate together within the resonant base to achieve resonance. When the resonant unit 2 adopts a combination of the resonant body and the main support 7, the support beam unit should be connected to the main support 7.

[0036] In one embodiment of the present invention, the resonant body may include a resonant electrode unit and a piezoelectric layer 9. The piezoelectric layer 9 corresponds to the two resonant electrodes within the resonant electrode unit. Specifically, the piezoelectric layer 9 corresponds to the two resonant electrodes, and at least the piezoelectric layer 9 can be used to separate and insulate the two resonant electrode layers. In a specific implementation, when the resonant electrode unit includes two resonant electrode layers, one resonant electrode layer can be used as the resonant bottom electrode 8, and the other resonant electrode layer can be used as the resonant top electrode 14. The resonant bottom electrode 8 is located between the resonant top electrode 14 and the main support body 7. Generally, the resonant bottom electrode 8 is located on the main support body 7, while the resonant top electrode 14 is located directly above the resonant bottom electrode 8.

[0037] In practical implementation, the two resonant electrode layers within the resonant electrode unit can adopt the same form; of course, the two resonant electrode layers can also adopt different forms. To effectively improve the electric field excitation efficiency, effectively suppress parasitic modes, and improve the quality factor of the piezoelectric resonator, preferably, the two resonant electrode layers within the resonant electrode unit adopt the same form. Specifically, each resonant electrode layer includes two resonant electrode sheet groups, each resonant electrode sheet group includes multiple resonant electrode sheets 15, and each resonant electrode sheet 15 is fan-shaped. Figure 1 and Figure 2 The image shows an embodiment of the resonant electrode sheet assembly within the resonant top electrode 14, which is composed of... Figure 1 and Figure 2 In this structure, each resonant electrode sheet group includes three resonant electrode sheets 15, each of which is fan-shaped. Six resonant electrode sheets 15 are arranged circumferentially along the ring resonator unit 2, and the six resonant electrode sheets 15 enclose a ring.

[0038] It should be noted that the resonant body of the present invention includes a resonant bottom electrode 8 and a resonant top electrode 14, and both the resonant bottom electrode 8 and the resonant top electrode 14 include a plurality of fan-shaped resonant electrode plates 15. By utilizing the resonant bottom electrode 8 and the resonant top electrode 14 in conjunction with the piezoelectric layer 9, the electric field distribution around the piezoelectric layer 9 can be altered. Based on the fan-shaped shape of the resonant electrode plates 15, the electric field generated by the resonant electrode plates 15 is more uniformly distributed within the resonant body unit 2 and matches the vibration mode of the target vibration mode. Furthermore, the electric field generated by the fan-shaped resonant electrode plates 15 can better excite the tangential vibration of the resonant body unit 2, enabling the electric field energy to be more efficiently converted into the mechanical energy of the target vibration mode, thereby improving the mode excitation efficiency.

[0039] In one embodiment of the present invention, a resonator hole 18 is provided within the resonator unit 2, wherein, The resonator hole 18 passes through the resonator body and the main support body 7; The resonant electrode plates 15 are symmetrically arranged on the outer ring of the resonant body hole 18, and the width of the resonant electrode plates 15 gradually increases along the direction from the center of the resonant body hole 18 to the outer edge of the resonant body unit. The outer edge of the resonant electrode 15 is adjacent to the outer edge of the resonant unit 2, and the inner edge of the resonant electrode 15 is adjacent to the resonant hole 18.

[0040] Figure 1 and Figure 2 The figure shows an embodiment in which a resonator hole 18 is provided in the resonator unit 2. As can be seen from the figure, the resonator hole 18 can be circular. The resonator hole 18 is located in the central area of ​​the resonator unit 2, that is, the resonator hole 18 and the resonator unit 2 are coaxially distributed. The resonator hole 18 penetrates the resonator body and the main support body 7. That is, the resonator hole 18 should penetrate the resonator top electrode 14, the piezoelectric layer 9, the resonator bottom electrode 8 and the main support body 7. In this case, the resonator unit 2 of the present invention is in the form of a circular column.

[0041] In specific implementation, the resonant electrode 15 is symmetrically distributed on the outer ring of the resonant body hole 18. The inner edge of the resonant electrode 15 is adjacent to the resonant body hole 18, and the outer edge of the resonant electrode 15 is adjacent to the outer edge of the resonant body unit 2. Generally, the outer edge of the resonant body unit 2 is determined by the piezoelectric layer 9, and the outer edge of the resonant top electrode 14 is located inside the outer edge of the resonant body unit 2.

[0042] Since the resonator hole 18 and the resonator unit 2 are coaxially distributed, Figure 2 The figure shows one embodiment of the outer diameter correspondence. Figure 2In this diagram, radius R1 is the radius of the resonator unit 2, radius R2 is the radius of the resonator aperture 18, radius R3 is the radius of the outer edge of the resonator top electrode 14 (i.e., the distance from the center of the resonator aperture 18 to the outer edge of the resonator top electrode 14), and radius R4 is the radius of the inner edge of the resonator top electrode 14 (i.e., the distance from the center of the resonator aperture 18 to the inner edge of the resonator top electrode 14). Specifically, the distribution of the resonator electrode sheet 15 avoids the outer and inner edges of the resonator unit 2, thereby preventing necessary edge effects and charge leakage.

[0043] Depend on Figure 1 , Figure 2 As explained above, the inner edge of the resonant top electrode 14 is the same as the inner edge of the resonant electrode piece 15, and the outer edge of the resonant top electrode 14 is the same as the outer edge of the resonant electrode piece 15. Therefore, the outer edges of all resonant electrode pieces 15 are located on the same circle, and the inner edges of all resonant electrode pieces 15 are also located on the same circle. A resonant hole 18 is provided within the resonant unit 2. The resonant hole 18 helps to form pure radial or contour-extended vibration modes, which in turn helps to configure the target vibration mode of the resonant unit 2.

[0044] In one embodiment of the present invention, for each resonant electrode layer, the number of resonant electrode sheets 15 in each resonant electrode sheet group is consistent, and the two resonant electrode sheet groups are centrally symmetrically distributed. The distribution of the resonant electrode sheets 15 within the resonant electrode layer is aligned with the strain antinode region of the target vibration mode of the resonant body unit 2, so as to maximize the electromechanical conversion efficiency and suppress non-target modes.

[0045] Specifically, for each resonant electrode layer, the number of resonant electrode sheets 15 within each resonant electrode sheet group is consistent, such as... Figure 1 and Figure 2 In the figure, each resonant electrode group includes three resonant electrode pieces 15. The three upper resonant electrode pieces 15 form one group of resonant electrode pieces, and the three lower resonant electrode pieces form another group of resonant electrode pieces. The resonant electrode pieces 15 in the two groups of resonant electrode pieces are centrally symmetrically distributed. Therefore, as mentioned above, the resonant electrode pieces 15 are symmetrically arranged on the outer ring of the resonant body hole 18. Specifically, the resonant electrode pieces 15 are centrally symmetrically distributed on the outer ring of the resonant body hole 18. At this time, the target mode with symmetry can be accurately matched, improving the mode purity and excitation efficiency. At the same time, multiple resonant electrode pieces 15 work together to drive the driving voltage to multiple equivalent positions, effectively enhancing the electro-mechanical conversion efficiency and supporting the stable excitation of higher-order symmetrical modes.

[0046] like Figure 2In the diagram, from left to right, the three upper resonant electrode plates 15 are respectively called: the first group of first resonant electrode plates, the first group of second resonant electrode plates, and the first group of third resonant electrode plates. The three lower resonant electrode plates 15 can be respectively called: the second group of first resonant electrode plates, the second group of second resonant electrode plates, and the second group of third resonant electrode plates. When centrally symmetrically distributed, the first group of first resonant electrode plates and the second group of third resonant electrode plates 15 are symmetrically distributed, the first group of second resonant electrode plates and the second group of second resonant electrode plates are symmetrically distributed, and the first group of third resonant electrode plates and the second group of first resonant electrode plates are symmetrically distributed.

[0047] It should be understood that a corresponding target vibration mode can be determined for each resonator unit 2. Specifically, since the resonator unit 2 is cylindrical, the target vibration mode of the resonator unit 2 specifically refers to the characteristic of the vibration mode distribution along the contour or perimeter of the resonator unit 2 under its circular geometry. When determining the target vibration mode of the resonator unit 2, the strain antinode region of the target vibration mode of the resonator unit 2 can be determined. At this time, the distribution position of the resonant electrode plate 15 should be aligned with the strain antinode region of the target vibration mode of the resonator unit 2 to maximize the electromechanical conversion efficiency and suppress non-target modes. The strain antinode region of the target vibration mode generally refers to the spatial region with the largest strain amplitude in the target vibration mode. At this time, the compression or tensile deformation of the resonator body can reach the extreme value.

[0048] In one embodiment of the present invention, based on the target vibration mode of the resonator unit 2, the electrical connection state between the resonant electrode sheets 15 within each resonant electrode layer is configured, wherein... When two adjacent resonant electrode plates 15 are electrically connected, a narrow metal connecting beam 21 is provided between the resonant electrode plates 15. The two ends of the narrow metal connecting beam 21 are in contact with and electrically connected to the resonant electrode plates 15 on both sides, and the width of the narrow metal connecting beam 21 is much smaller than the fan-shaped length of the resonant electrode plate 15.

[0049] It should be understood that the resonant electrode pieces 15 within each resonant electrode layer should be configured with electrical connections, that is, the corresponding resonant bottom electrode 8 and resonant top electrode 14 can be formed based on the electrical connections between the resonant electrode pieces 15. Specifically, when configuring the electrical connections between the resonant electrode pieces 15 within each resonant electrode layer, it should be based at least on the target vibration mode of the resonant body unit 2. Figure 1 and Figure 2 The figure illustrates one embodiment of the electrical connection state between the resonant electrode plates 15. In the figure, the first group of first resonant electrode plates, the first group of second resonant electrode plates, and the first group of third resonant electrode plates are connected sequentially, and the first group of third resonant electrode plates is connected in series with the second group of third resonant electrode plates, the second group of second resonant electrode plates, and the second group of first resonant electrode plates. Figure 1 and Figure 2 In this configuration, six resonant electrode plates 15 are connected in series, and after being connected in series, a corresponding target vibration mode of the resonant body unit 2 can be obtained. Other connection methods can be selected as needed, and will not be illustrated here.

[0050] In a specific implementation, when two adjacent resonant electrode plates 15 are electrically connected, a narrow metal connecting beam 21 is provided between the resonant electrode plates 15. Subsequently, the narrow metal connecting beam 21 is electrically connected to the two corresponding resonant electrode plates 15. Generally, the width of the narrow metal connecting beam 21 is much smaller than the fan-shaped length of the resonant electrode plate 15, so that it will not affect the matching of the vibration mode with the target vibration mode of the resonant body unit 2.

[0051] Figure 1 and Figure 2 In this design, an inter-plate isolation hole 20 is provided between adjacent resonant electrode plates 15. A narrow metal connecting beam 21 is fabricated within the inter-plate isolation hole 20. The inter-plate isolation hole 20 separates two adjacent resonant electrode plates 15. When the narrow metal connecting beam 21 is provided within the inter-plate isolation hole 20, the inter-plate isolation hole 20 is divided into two mutually isolated regions. It should be noted that the width of the narrow metal connecting beam 21 is much smaller than the fan-shaped length of the resonant electrode plate 15. The design of the narrow metal connecting beam 21 helps to balance the stress of the resonant electrode plate 15, improve the mechanical stability and structural consistency of the overall resonant electrode layer, and enhance the structural stability of the piezoelectric resonator. The fan-shaped length of the resonant electrode plate 15 specifically refers to the distance between the inner edge and the corresponding outer edge of the resonant electrode plate 15. The width of the narrow metal connecting beam 21 specifically refers to the corresponding dimension of the narrow metal connecting beam 21 in the direction from the outer edge to the inner edge of the resonant electrode plate 15.

[0052] In specific implementation, within each resonant electrode layer, the angle of the resonant electrode sheet 15 is 30°~80°. The size of the angle of the resonant electrode sheet 15 can correspond to the target vibration mode of the resonant body unit 2. Specifically, the angle of the resonant electrode sheet 15 refers to the fan angle corresponding to each fan-shaped resonant electrode sheet 15.

[0053] In one embodiment of the present invention, within each resonant electrode layer, an anchor point loss mitigation opening 19 is configured to avoid the stress belly position of the target vibration mode, wherein, The anchor point loss mitigation opening 19 is trumpet-shaped, and the opening of the anchor point loss mitigation opening 19 gradually increases along the direction from the center of the resonant body to the edge of the resonant body unit. Within the resonant electrode layer, the resonant electrode pieces 15 located on both sides of the anchor point loss mitigation opening 19 are in a non-contact electrical connection state through the anchor point loss mitigation opening 19.

[0054] To further improve the excitation efficiency of the target vibration mode of the resonator element 2, anchor point loss mitigation openings 19 can be set in each resonant electrode layer. The position of the anchor point loss mitigation openings 19 should avoid the stress belly position of the target vibration mode of the resonator element 2. It should be noted that after the target vibration mode of the resonator element 2 is determined, the stress belly position can be determined accordingly. Figure 1 and Figure 2 The figure shows an embodiment in which the anchor point loss mitigation opening 19 is distributed within the resonant top electrode 14. In the figure, the anchor point loss mitigation opening 19 is located between the first group of first resonant electrode sheets and the second group of first resonant electrode sheets, that is, the area between the first group of first resonant electrode sheets and the second group of first resonant electrode sheets is the non-stressed belly position.

[0055] Figure 1 and Figure 2 In this design, the anchor point loss mitigation opening 19 is trumpet-shaped, and its opening gradually increases along the direction from the center of the resonant body to the edge of the resonant unit. That is, along the length of the anchor point loss mitigation opening 19, and from the center of the resonant hole 18 to the opening of the resonant efficiency enhancement opening 19, the opening gradually increases. Furthermore, the aforementioned narrow metal connecting beam 21 should be avoided within the resonant efficiency enhancement opening 19. This means that the resonant electrode plates 15 positioned on both sides of the anchor point loss mitigation opening 19 are in a non-contact electrical connection state. As explained above, the anchor point loss mitigation opening 19 allows for a non-contact electrical connection between the first group of first resonant electrode plates and the second group of first resonant electrode plates; that is, the first group of first resonant electrode plates and the second group of first resonant electrode plates are not directly connected by the narrow metal connecting beam 21.

[0056] In specific implementation, the opening width of the anchor point loss mitigation opening 19 should be greater than the opening width of the inter-plate isolation hole 20 mentioned above. The anchor point loss mitigation opening 19 can make the driving resonant electrode plate 15 aligned with the strain antinode. The anchor point loss mitigation opening 19 is located at the contact point between the support beam unit and the resonant body unit 2, thereby forming a soft connection boundary in terms of mechanical transmission and mitigating anchor point loss.

[0057] It should be noted that the two resonant electrode layers can adopt the same structure and arrangement as the resonant electrode sheet 15, that is, both the bottom resonant electrode 8 and the top resonant electrode 14 have anchor point loss mitigation openings 19, and preferably, the two anchor point loss mitigation openings 19 are aligned. Of course, the two anchor point loss mitigation openings 19 can also adopt other arrangements, which can be selected according to the specific needs.

[0058] In one embodiment of the present invention, a support beam unit provides axial support for the resonator unit 2, and the support beam unit includes at least two support beams 5, wherein... The support beam 5 is suspended in the resonant base. One end of the support beam 5 is adapted to the resonant base, and the other end of the support beam 5 is connected to the main support body 7 of the resonant unit. The contact connection between the support beam 5 and the main support body 7 is located near the displacement node of the vibration mode of the resonant unit 2. The connection between the support beam 5 and the main support body 7 is used to form a double beam support structure to improve the stability of the resonant body.

[0059] As explained above, the resonator unit 2 is circular. Axial support for the resonator unit 2 can be achieved using support beam units. Generally, each support beam unit can include at least two support beams 5. Of course, other numbers of support beams 5 can also be included within the support beam unit. The number of support beams 5 can be selected according to actual needs, and all support beams 5 provide axial support for the resonator unit 2. Figure 1 and Figure 2 The image shows an embodiment in which two support beams 5 are arranged within the support beam unit.

[0060] In practical implementation, the support beam 5 is also suspended within the resonant base; that is, both the support beam 5 and the resonant element 2 are suspended. Figure 1 As shown. The support beam 5 can generally be long and narrow. One end of the support beam 5 is adapted to the resonant base, and the other end of the support beam 5 is connected to the main support body 7 of the resonant unit.

[0061] To suppress the leakage of vibrational energy to the resonant base, improve mechanical stability, and adapt to the symmetry of the target vibration mode, the contact connection between the support beam 5 and the main support body 7 is located near the displacement node of the vibration mode of the resonant unit 2. Specifically, the displacement node refers to the spatial position where the displacement amplitude is zero in the target vibration mode. Furthermore, the connection between each support beam 5 and the main support body 7 forms a double-beam support structure to improve the stability of the resonant body. It should be noted that the formed double-beam support structure ensures that the resonant body remains stable during modal excitation, thereby enabling the resonant body to operate stably in the target vibration mode and improving the stability and repeatability of modal excitation.

[0062] In one embodiment of the present invention, when the support beam unit includes two support beams 5, the two support beams 5 are coaxially symmetrically distributed, and one support beam 5 corresponds to the opening direction of the anchor point loss mitigation opening 19.

[0063] Figure 1 and Figure 2 The diagram shows an embodiment in which the support beam unit includes two support beams 5, and the two support beams 5 are coaxially symmetrically distributed. In this case, the line connecting the two support beams 5 passes through the axis of the resonator hole 18 and the center of the resonator base. Figure 2In the middle, the support beam 5 on the left corresponds to the efficiency improvement opening 19, and the support beam 5 and the anchor point loss reduction opening 19 are also coaxially distributed to further improve the excitation efficiency.

[0064] In addition, by Figure 1 It is known that a bottom electrode lead-out membrane 10 and a piezoelectric lead-out body 13 located on the bottom electrode lead-out membrane 10 are also provided on each resonant support beam 5. Generally, the bottom electrode lead-out membrane 10 is electrically connected to the resonant bottom electrode 8, and the bottom electrode lead-out membrane 10 and the resonant bottom electrode 8 can be prepared using the same process. The resonant bottom electrode 8 is electrically connected to the base bottom electrode ring 3 through the bottom electrode lead-out membrane 10. Of course, the base bottom electrode ring 3 can also generally be prepared using the same process as the bottom electrode lead-out membrane 10 and the resonant bottom electrode 8.

[0065] Figure 1 In this design, a base piezoelectric ring 4 is disposed on the base bottom electrode ring 3. The base piezoelectric ring 4, the piezoelectric lead 13, and the piezoelectric layer 9 can generally be fabricated using the same process. After the base piezoelectric ring 4 covers the base bottom electrode ring 3, a bottom electrode ring window 11 should be provided on the base piezoelectric ring 4 to facilitate external electrical connection, thereby exposing the base bottom electrode ring 3.

[0066] To bring out the resonant top electrode 14, a top electrode lead-out body 16 should be provided. The top electrode lead-out body 16 is located above a support beam 5, specifically on the piezoelectric lead-out body 13 of the corresponding support beam 5. One end of the top electrode lead-out body 16 is electrically connected to a narrow metal connecting beam 21, and the other end is electrically connected to a top electrode connection end 17. Generally, the top electrode connection end 17 and the bottom electrode ring window 11 are correspondingly distributed. Figure 1 As shown.

[0067] As can be seen from the above explanation, Figure 1 The resonant base only shows one embodiment of the top silicon layer 1. Generally, the top silicon layer 1 should be the upper silicon layer of an SOI (silicon-on-insulator) substrate. That is, the resonant base should also include a lower silicon layer and a buried oxide layer within the SOI substrate. In order to enable the resonator unit 2 and the support beam 5 to be suspended, the top silicon layer 1 should generally be etched, the buried oxide layer should be released, and a [structure / form] should be formed. Figure 1 The base suspension groove 6 allows the resonator unit 2 and the support beam 5 to be suspended in the air. It should be noted that when using an SOI substrate, the main support 7, the support beam 5, and the top silicon layer 1 are all formed from the upper silicon layer.

[0068] When the piezoelectric resonator operates in piezoelectric drive mode, an AC drive voltage is applied to the top electrode connection terminal 17, and the resonant bottom electrode 8 is grounded through the bottom electrode ring window 11. When the frequency of the AC drive high voltage approaches the natural frequency of the piezoelectric resonator of this invention, the piezoelectric layer 9 generates an inverse piezoelectric effect under the action of the alternating electric field, exciting the ring-shaped resonant body to generate a stable vibration mode. The natural frequency of the piezoelectric resonator is the resonant frequency determined according to the structure of the piezoelectric resonator. Generally, the natural frequency is the natural vibration frequency under undamped and unforced conditions. The natural frequency of the piezoelectric resonator can be determined using techniques commonly used in this technical field. Conversely, when the resonant body is subjected to external mechanical disturbance, its vibration will cause strain in the piezoelectric layer 9. The generated charge signal can be detected through the resonant bottom electrode 8 and the resonant top electrode 9 to detect the vibration state of the resonant body.

[0069] Figure 3 In response to Figure 1 The diagram shows a simulation result of an embodiment of modal simulation of a piezoelectric resonator. During the simulation, the parameters of the piezoelectric resonator are: R1=180μm, R2=60μm, R3=170μm, R4=50μm, the width of the support beam 5 is 50μm, the beam length of the support beam 5 is 150μm, the thickness of the bottom resonant electrode 8 and the top resonant electrode 14 is 200nm, the thickness of the piezoelectric layer 9 is 1μm, and the angle of each resonant electrode 15 is 50°. In addition, a bias DC voltage of 1V should be applied to the top resonant electrode 14, and the bottom resonant electrode 8 should be grounded. As shown in the figure, the simulation results show that the vibration displacement energy is highly concentrated in the annular area covered by the fan-shaped resonant electrode 15. The modal shape is clear and pure, and no obvious parasitic modes are observed, indicating that the fan-shaped resonant electrode 15 effectively matches and excites the target vibration mode.

[0070] Furthermore, Figure 3 In the simulation, the alternating red and blue areas are periodically distributed around the circumference of the ring, indicating that the main vibration direction of the resonator is along the circumference of resonator unit 2. The red area represents the point of maximum displacement, and the blue area represents the stationary point (almost stationary), which conforms to the standing wave form. In the simulation, resonator unit 2 exhibits six alternating red and blue regions (alternating high and low displacements), which indicates that it may be a sixth-order mode. No radial expansion / contraction was observed in the structure (not a breathing mode), which distinguishes it from the traditional structure, proving that the piezoelectric resonator of this invention is more likely to excite higher-order modes.

[0071] Figure 4 This is a schematic diagram illustrating an embodiment of obtaining the admittance curve for the piezoelectric resonator of the present invention. The admittance curve results show that the resonant frequency (fr) is approximately 926.6 kHz, and the anti-resonant frequency (far) is approximately 926.9 kHz. Substituting into the mechanical coupling coefficient formula... The mechanical coupling coefficient in this embodiment is 0.06472%. The quality factor Q of the piezoelectric resonator is calculated using the half-power point method, and the specific calculation formula is: Q = Where f1 and f2 are the resonant frequencies at the point where the peak value of the admittance curve drops by 3dB, and f2-f1 is the -3dB bandwidth. According to the calculation results from the formula, the quality factor Q can reach 2000.

[0072] Figure 4 The horizontal axis represents the frequency of the piezoelectric resonator, and the vertical axis represents the admittance in decibels. Figure 4 In the diagram, M1 is the resonant frequency of the piezoelectric resonator of the present invention, and M2 is the anti-resonant frequency of the piezoelectric resonator of the present invention.

[0073] The piezoelectric resonator described above can be prepared by the following process steps, specifically, the preparation method includes: A resonant substrate is provided, wherein the resonant substrate includes a substrate bottom layer, a sacrificial layer disposed on the substrate bottom layer, and a substrate top layer disposed on the sacrificial layer; A bottom electrode film is prepared on the top layer of the substrate, and the bottom electrode film is patterned to form a resonant bottom electrode 8 after patterning. A piezoelectric base layer and a top electrode film are sequentially prepared on the resonant bottom electrode 8. Then, the top electrode film is patterned to form the resonant top electrode 14 after patterning. The piezoelectric base layer and the top layer of the substrate are patterned sequentially to form a piezoelectric layer 9 after the piezoelectric base layer is patterned, and at least a main support body 7 and a support beam unit are formed after the top layer of the substrate is patterned, and a sacrifice release window for releasing the sacrifice layer is formed. The sacrificial layer is released using the sacrificial release window formed above, so as to form a suspended resonator unit 2 and a supporting beam unit.

[0074] As can be seen from the above description, the resonant substrate can be an SOI substrate. When the resonant substrate is an SOI substrate, the lower silicon layer can be used to form the substrate bottom layer, the buried oxide layer can be used to form the sacrificial layer, and the upper silicon layer can be used to form the substrate top layer. When the resonant substrate adopts other forms, the specific criteria are based on the ability of the resonant substrate to have a substrate bottom layer, a sacrificial layer, and a substrate top layer. The substrate bottom layer and the substrate top layer are silicon layers, and the sacrificial layer can be a silicon dioxide layer.

[0075] A bottom electrode film can be prepared on the top layer of the substrate using processes such as magnetron sputtering. The material of the bottom electrode film can be metallic molybdenum (Mo), and the thickness of the bottom electrode film can be 200 nm. The bottom electrode film generally completely covers the top layer of the substrate. Subsequently, the bottom electrode film is patterned to form a resonant bottom electrode 8. When patterning the bottom electrode film, commonly used patterning methods can be used, such as placing photoresist on the bottom electrode film and developing and exposing the photoresist. Subsequently, the bottom electrode film is etched to form the resonant bottom electrode 8. The situation of obtaining the resonant bottom electrode 8 by etching can be referred to the above description. Of course, as can be seen from the above description, when forming the resonant bottom electrode 8, a base bottom electrode ring 3 and a bottom electrode lead-out film 10 can also be formed. The situation of the resonant bottom electrode 8, the base bottom electrode ring 3, and the bottom electrode lead-out film 10 can be referred to the above description, and will not be repeated here.

[0076] After the resonant bottom electrode 8 is prepared, a piezoelectric base layer and a top electrode film should be prepared on the resonant bottom electrode. The piezoelectric base layer can be aluminum nitride (AlN) and the thickness of the piezoelectric base layer can be 1 μm. After the piezoelectric base layer is prepared, it will cover the base bottom electrode ring 3 and the bottom electrode lead-out film 10, cover the resonant electrode sheet 15 of the resonant bottom electrode 8, and fill the inter-sheet isolation holes 20 between the resonant electrode sheets 15. In addition, the piezoelectric base layer will also cover the corresponding area of ​​the top layer of the substrate.

[0077] After the piezoelectric base layer is prepared, a top electrode film can be prepared by magnetron sputtering. The top electrode film can be identical to the bottom electrode film, as detailed in the above description. The top electrode film will completely cover the piezoelectric base layer. After the top electrode film is prepared, it should be patterned. The method and process for patterning the top electrode film can be referred to the above description of patterning the bottom electrode film, and will not be repeated here. It is understood that after patterning the top electrode film, at least a resonant top electrode 14 can be formed. The details of the resonant top electrode 14 can be referred to the above description. In addition, as described above, a top electrode lead-out body 16 and a top electrode connection terminal 17 should also be formed.

[0078] After the resonant top electrode 14 is fabricated, the piezoelectric substrate should be patterned. Patterning the piezoelectric substrate should generate a piezoelectric layer 9. Additionally, a piezoelectric lead-out 13 and a base piezoelectric ring 4 should be obtained simultaneously. The remaining area can be used as a window for patterning the top layer of the substrate. Furthermore, a bottom electrode ring window 11 can be obtained before patterning the piezoelectric substrate, during the patterning process, or before fabricating the top electrode film. The details of the piezoelectric layer 9, the base piezoelectric ring 4, the bottom electrode ring window 11, and the piezoelectric lead-out 13 are as described above and will not be repeated here.

[0079] After the piezoelectric layer 9 is prepared, the top layer of the substrate is patterned using techniques commonly used in this field. After patterning, at least the main support 7 and support beam units are formed. The details of the main support 7 and support beam units can be found in the corresponding descriptions above. Furthermore, when patterning the top layer 9, it should be patterned until the sacrificial layer is exposed, thus forming a sacrificial release window for releasing the sacrificial layer.

[0080] After the sacrificial release window is formed, the sacrificial layer should be released using the aforementioned sacrificial release window to form the suspended resonator unit 2 and the supporting beam unit. The process conditions and methods for releasing the sacrificial layer can be consistent with existing technologies, aiming to effectively form the resonator unit 2 and the supporting beam unit, and to form the base suspension groove 6. It should be understood that during the entire process, the bottom layer of the substrate is processed. Of course, subsequent processing can be performed on the bottom layer of the substrate, and the subsequent processing methods can be consistent with existing technologies, which will not be elaborated here.

[0081] In one embodiment of the present invention, a seed layer is prepared on the top layer of the substrate before the bottom electrode film is prepared, and then the bottom electrode film is prepared on the seed layer. When patterning the piezoelectric substrate, the corresponding seed layer is etched and removed at the same time as the piezoelectric substrate is etched. After patterning the piezoelectric substrate and the top layer of the substrate, a resonator hole 18 is formed that penetrates the resonator unit.

[0082] Specifically, when a seed layer is prepared on the top layer of the substrate, the adhesion of the subsequent underlying electrode film can be improved, and cracks that may occur in the subsequently deposited metal film can be avoided. The seed layer can be made of existing materials, and the preparation process of the seed layer can be consistent with existing technologies, which will not be elaborated here.

[0083] When a seed layer exists, during the patterning of the piezoelectric substrate, the corresponding seed layer is etched away simultaneously with the etching of the piezoelectric substrate. Furthermore, after patterning the piezoelectric substrate and the top layer of the substrate, a resonator hole 18 is formed that penetrates the resonator unit. The details of the formed resonator hole 18 can be found in the above description; the resonator hole 18 can be interconnected with the base suspension groove 6.

[0084] In specific implementation, when patterning the bottom electrode film, after obtaining the resonant bottom electrode 8, a bottom electrode through-hole corresponding to the resonant body hole 18 can also be obtained. After preparing the piezoelectric base layer, the piezoelectric base layer will fill the bottom electrode through-hole. When patterning the top electrode film, after obtaining the resonant top electrode 14, a top electrode through-hole corresponding to the resonant body hole 18 can also be obtained. Subsequently, the piezoelectric base layer is patterned using the top electrode through-hole to remove the portion corresponding to the top electrode through-hole to obtain the resonant body hole 18. That is, during removal, the piezoelectric base layer filling the bottom electrode through-hole is also removed. After patterning the top layer of the substrate, the corresponding portion of the top layer of the substrate is removed using the top electrode through-hole and the bottom electrode through-hole to obtain the resonant body hole 18.

[0085] As can be seen from the above description, the piezoelectric resonator of the present invention can be fabricated using MEMS technology. First, a resonant bottom electrode 8 is fabricated. Then, a resonant top electrode 14 is fabricated on a piezoelectric substrate. After the resonant bottom electrode is fabricated, a piezoelectric layer is fabricated. Finally, the top layer of the substrate is patterned, and the sacrificial layer is released. The entire fabrication process has high patterning accuracy and alignment tolerance, and the pattern boundaries are clear, ensuring that the distribution of the resonant electrode sheet 15 is aligned with the antinodes of the target vibration mode strain wave, thereby maximizing the electromechanical conversion efficiency.

[0086] Furthermore, the above-mentioned fabrication process allows for rapid adjustment of the number, angle, or layout of the support beams 5 of the resonant electrode sheets 15 within each resonant electrode layer, thereby adapting to different target vibration modes and improving the compatibility and adaptability of the process.

Claims

1. A piezoelectric resonator with a high Q value, characterized in that, The piezoelectric resonator includes: Resonant base; The resonant element is cylindrical and suspended within the resonant base. The resonant element is connected to the resonant base via supporting beam elements, and can vibrate within the resonant base. The resonator unit includes a resonator body and a main support body for supporting the resonator body, and is adapted to be connected to the support beam unit through the main support body. The resonant body includes a resonant electrode unit and a piezoelectric layer. The resonant electrode unit includes two resonant electrode layers, and the piezoelectric layer corresponds to the two resonant electrode layers in the resonant electrode unit. One resonant electrode layer is used as the bottom resonant electrode, and the other resonant electrode layer is used as the top resonant electrode. The bottom resonant electrode is located on the main support body. For any resonant electrode layer, the resonant electrode layer includes two resonant electrode sheet groups, each resonant electrode sheet group includes several resonant electrode sheets, each resonant electrode sheet is fan-shaped, and the resonant electrode sheets in the resonant electrode layer are arranged circumferentially along the ring resonator unit, so as to configure the resonant electrode sheets in the resonant electrode layer to form a ring.

2. The high-Q piezoelectric resonator according to claim 1, characterized in that: The support beam unit provides axial support to the resonator unit, and the support beam unit includes at least two support beams. The support beam is suspended within the resonant base. One end of the support beam is adapted to the resonant base, and the other end of the support beam is connected to the main support of the resonant unit. The contact connection between the support beam and the main support is located near the displacement node of the vibration mode of the resonant unit. This connection between the support beam and the main support forms a double-beam support structure to improve the stability of the resonant unit.

3. The high-Q piezoelectric resonator according to claim 1, characterized in that: in The resonator unit is provided with a resonator hole, wherein... The resonator hole penetrates the resonator body and the main support body; The resonant electrode plates are symmetrically arranged on the outer ring of the resonant body hole, and the width of the resonant electrode plates gradually increases along the direction from the center of the resonant body hole to the outer edge of the resonant body unit. The outer edge of the resonant electrode is adjacent to the outer edge of the resonant element, and the inner edge of the resonant electrode is adjacent to the resonant hole.

4. The high-Q piezoelectric resonator according to claim 2, characterized in that: For each resonant electrode layer, the number of resonant electrode sheets in each resonant electrode sheet group is consistent, and the two resonant electrode sheet groups are centrally symmetrically distributed. The distribution of the resonant electrode sheets within the resonant electrode layer is aligned with the strain antinode region of the target vibration mode of the resonant body unit to maximize electromechanical conversion efficiency and suppress non-target modes.

5. The high-Q piezoelectric resonator according to claim 4, characterized in that: Based on the target vibration mode of the resonant body unit, the electrical connection state between the resonant electrode plates within each resonant electrode layer is configured, wherein... When two adjacent resonant electrode plates are electrically connected, a narrow metal connecting beam is provided between the resonant electrode plates. The two ends of the narrow metal connecting beam are in contact with and electrically connected to the resonant electrode plates on both sides, and the width of the narrow metal connecting beam is much smaller than the fan-shaped length of the resonant electrode plates.

6. The high-Q piezoelectric resonator according to claim 5, characterized in that: in Within each resonant electrode layer, anchor point loss mitigation openings are configured to avoid the stress belly position of the target vibration mode. The anchor point loss mitigation opening is funnel-shaped, and the opening gradually increases in size along the direction from the center of the resonant body to the edge of the resonant unit. Within the resonant electrode layer, the resonant electrode sheets located on both sides of the anchor point loss mitigation opening are in a non-contact electrical connection state through the anchor point loss mitigation opening.

7. The high-Q piezoelectric resonator according to claim 6, characterized in that: When the support beam unit includes two support beams, the two support beams are coaxially symmetrically distributed, and one support beam corresponds to the opening direction of the anchor point loss mitigation opening.

8. The high-Q piezoelectric resonator according to any one of claims 1 to 7, characterized in that: Within each resonant electrode layer, the angle of the resonant electrode sheet is 30° to 80°.

9. A method for fabricating a high-Q piezoelectric resonator, characterized by: The method for preparing a piezoelectric resonator according to any one of claims 1 to 8 comprises: A resonant substrate is provided, wherein the resonant substrate includes a substrate bottom layer, a sacrificial layer disposed on the substrate bottom layer, and a substrate top layer disposed on the sacrificial layer; A bottom electrode film is prepared on the top layer of the substrate, and the bottom electrode film is patterned to form a resonant bottom electrode after patterning. A piezoelectric base layer and a top electrode film are sequentially prepared on the above-mentioned resonant bottom electrode. Then, the top electrode film is patterned to form a resonant top electrode after patterning. The piezoelectric base layer and the top layer of the substrate are patterned sequentially to form a piezoelectric layer after the piezoelectric base layer is patterned, and at least the main support body and the support beam unit are formed after the top layer of the substrate is patterned, and a sacrifice release window for releasing the sacrifice layer is formed. The sacrificial layer is released using the sacrificial release window formed above, so as to form a suspended resonator unit and a supporting beam unit.

10. The method for fabricating a high-Q piezoelectric resonator according to claim 9, characterized in that: Before fabricating the bottom electrode, a seed layer is prepared on the top layer of the substrate, and then the bottom electrode is fabricated on the seed layer. When patterning the piezoelectric substrate, the corresponding seed layer is etched and removed simultaneously with the etching of the piezoelectric substrate. Furthermore, after patterning the piezoelectric substrate and the top layer of the substrate, a resonator hole that penetrates the resonator unit is also formed.

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