Vertical electric field excited bulk acoustic wave resonator device

Abstract

The application relates to the technical field of bulk acoustic wave resonators, in particular to a vertical electric field excitation bulk acoustic wave resonator device, which comprises, from bottom to top, a bottom electrode, a piezoelectric layer and a top electrode, the piezoelectric layer is a double-layer structure or a single-layer structure, and the device further comprises a diamond film; when the piezoelectric layer adopts the double-layer structure, the diamond film is arranged on the bottom surface of the bottom electrode and the piezoelectric layer, and / or arranged between the top electrode and the piezoelectric layer, and / or arranged between the upper and lower layers in the piezoelectric layer; when the piezoelectric layer adopts the single-layer structure, the diamond film is arranged on the bottom surface of the bottom electrode and the piezoelectric layer, and / or arranged between the top electrode and the piezoelectric layer. The vertical electric field excitation bulk acoustic wave resonator device provided by the application can effectively inhibit out-of-band parasitic modes, greatly weaken in-band transverse stray waves, significantly improve the quality factor while moving the resonant frequency to a high frequency band, and obviously improve the working stability, wafer-level consistency and product yield.

Description

Technical Field

[0001] This invention relates to the field of bulk acoustic resonator technology, and particularly to a vertically electric field-excited bulk acoustic resonator device. Background Technology

[0002] With the rapid development of communication technology, the demand for resonators in electronic devices has increased significantly. Among them, the vertical electric field exciter acoustic resonator (YBAR) has been widely used due to its greater coupling and more efficient resonance mode. It mainly consists of a substrate, a lower electrode, a piezoelectric layer and an upper electrode stacked from bottom to top.

[0003] However, existing vertical electric field exciter acoustic resonators have the following shortcomings:

[0004] (1) The suppression effect of out-of-band parasitic modes is limited, and there are many in-band transverse spurious waves, making it impossible to achieve higher resonant frequencies.

[0005] (2) The heat dissipation of the device is relatively slow, resulting in severe thermal temperature drift and affecting the working stability of the device.

[0006] (3) In the back-side release process, the lower electrode and piezoelectric layer are located above the release cavity. Back-side etching will erode the lower electrode and even the piezoelectric layer, affecting the wafer-level consistency and yield of the device. Summary of the Invention

[0007] In order to solve the problems existing in the prior art mentioned above, the present invention provides a vertical electric field exciter acoustic resonator device that effectively suppresses out-of-band parasitic modes, significantly weakens in-band transverse spurious waves, moves the resonant frequency to the high-frequency band, significantly improves the quality factor, and significantly enhances the operating stability, wafer-level consistency, and yield.

[0008] The technical solution adopted by this invention to solve its technical problem is: a vertical electric field exciter acoustic resonator device, comprising a bottom electrode, a piezoelectric layer, and a top electrode stacked sequentially from bottom to top. The piezoelectric layer is a double-layer structure or a single-layer structure, and also includes a diamond film. When the piezoelectric layer adopts a double-layer structure, the diamond film is disposed on the bottom electrode and the lower surface of the piezoelectric layer, and / or disposed between the top electrode and the piezoelectric layer, and / or disposed between the upper and lower layers of the piezoelectric layer; when the piezoelectric layer adopts a single-layer structure, the diamond film is disposed on the bottom electrode and the lower surface of the piezoelectric layer, and / or disposed between the top electrode and the piezoelectric layer.

[0009] Furthermore, an annular through-hole is formed on the diamond film, and the annular through-hole penetrates the diamond film in a vertical direction.

[0010] Furthermore, an annular groove is formed on the lower surface of the diamond film.

[0011] Furthermore, a central groove is formed at the center of the lower surface of the diamond film.

[0012] Furthermore, it also includes a substrate disposed on the lower surface of the entire vertical electric field exciter acoustic resonator.

[0013] Furthermore, it also includes a dielectric layer disposed on the upper surface of the substrate.

[0014] Furthermore, it also includes a Bragg reflector layer disposed between the substrate and the dielectric layer.

[0015] Furthermore, when the piezoelectric layer adopts a double-layer structure, with the diamond film disposed on the bottom electrode and the lower surface of the piezoelectric layer, the thickness of the diamond film is 3nm to 50nm, and the ratio of the thickness of the diamond film to the thickness of the piezoelectric layer is 0.006 to 0.10.

[0016] Furthermore, when the piezoelectric layer adopts a double-layer structure, and the diamond film is disposed between the upper and lower layers in the piezoelectric layer, the thickness of the diamond film is 1 nm to 20 nm.

[0017] Furthermore, when the piezoelectric layer adopts a double-layer structure, and the diamond film is disposed between the top electrode and the piezoelectric layer, the thickness of the diamond film is 1 nm to 15 nm.

[0018] The beneficial effects of this invention are:

[0019] (1) The present invention provides a diamond film on the lower surface of the bottom electrode and the piezoelectric layer. By utilizing the ultra-high volume sound velocity characteristics of diamond, the diamond film acts as a high sound velocity layer, introducing a high acoustic impedance difference boundary below the bottom electrode. This changes the acoustic boundary conditions in the vertical direction, causing the target SH2 mode frequency to shift upward, thereby effectively suppressing high-order parasitic modes outside the band and significantly weakening transverse stray waves within the band, achieving a pure response within the working bandwidth. At the same time, the diamond film can reduce the leakage of acoustic energy towards the substrate and enhance the localization of high-frequency acoustic waves within the piezoelectric layer. This not only improves the resonant frequency to the high-frequency band but also helps to improve the quality factor of the device.

[0020] (2) The present invention provides a diamond film on the lower surface of the bottom electrode and the piezoelectric layer. With the high thermal conductivity of diamond, the diamond film can serve as a highly efficient heat dissipation layer, which can quickly dissipate the Joule heat generated by the high-frequency vibration of the piezoelectric layer, reduce the risk of temperature rise, frequency drift and thermal failure, thereby comprehensively improving the working stability and power tolerance of the device under high power conditions. At the same time, the diamond film can also serve as an etching barrier layer in the back-side release etching process, reducing the risk of damage to the bottom electrode and piezoelectric layer by the back-side etching, which is conducive to maintaining the integrity of the suspended acoustic cavity structure and improving the wafer-level consistency and yield of the device.

[0021] (3) In this invention, a diamond film is provided on the lower surface of the bottom electrode and the piezoelectric layer. Relying on the high rigidity of diamond, the diamond film serves as a high rigidity support layer, which not only provides excellent mechanical support strength for the bottom electrode, but also plays a role in stress release and balance between heterogeneous integrated films, thereby greatly optimizing the device's resistance to mechanical shock. Attached Figure Description

[0022] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0023] Figure 1 This is a schematic diagram of the structure of the first vertical electric field exciter acoustic resonator device (the piezoelectric layer is a double-layer structure) in this invention.

[0024] Figure 2 yes Figure 1 A cross-sectional view along the AA direction.

[0025] Figure 3 This is a cross-sectional view along the AA direction of the second type of vertical electric field exciter acoustic resonator device (the piezoelectric layer has a double-layer structure) in this invention.

[0026] Figure 4 This is a schematic diagram of the structure of the third type of vertical electric field exciter acoustic resonator device (the piezoelectric layer is a single-layer structure) in this invention.

[0027] Figure 5 yes Figure 4 A cross-sectional view along the BB direction.

[0028] Figure 6 This is a cross-sectional view along the AA direction of the fourth type of vertical electric field exciter acoustic resonator device (with a double-layer piezoelectric layer) in this invention.

[0029] Figure 7 This is a cross-sectional view along the AA direction of the fifth type of vertical electric field exciter acoustic resonator device (the piezoelectric layer is a single-layer structure) in this invention.

[0030] Figure 8This is a cross-sectional view along the AA direction of the sixth type of vertical electric field exciter acoustic resonator device (with a double-layer piezoelectric layer) in this invention.

[0031] Figure 9 This is a cross-sectional view along the AA direction of the seventh type of vertical electric field exciter acoustic resonator device (the piezoelectric layer is a single-layer structure) in this invention.

[0032] Figure 10 This is a cross-sectional view along the AA direction of an existing vertical electric field exciter acoustic resonator device (the piezoelectric layer is a single-layer structure and a dielectric layer is provided) in this invention.

[0033] Figure 11 This is a cross-sectional view along the AA direction of the eighth type of vertical electric field exciter acoustic resonator device (with a double-layer piezoelectric layer) in this invention.

[0034] Figure 12 This is a cross-sectional view along the AA direction of the ninth type of vertical electric field exciter acoustic resonator device (the piezoelectric layer is a single-layer structure) in this invention.

[0035] Figure 13 This is a schematic diagram of the annular through hole in this invention.

[0036] Figure 14 This is a schematic diagram of the annular groove in this invention.

[0037] Figure 15 This is a schematic diagram of the central groove in this invention.

[0038] Figure 16 This is a schematic diagram of the tenth type of vertical electric field exciter acoustic resonator device (with a double-layer piezoelectric layer) in this invention.

[0039] Figure 17 This is a schematic diagram of the eleventh type of vertical electric field exciter acoustic resonator device (with a double-layer piezoelectric layer) in this invention.

[0040] Figure 18 This is the admittance-frequency curve of an existing vertical electric field exciter acoustic resonator (with a double-layer piezoelectric layer and no diamond film).

[0041] Figure 19 This is the admittance-frequency curve of the first type of vertical electric field exciter acoustic resonator (with a double-layer piezoelectric layer).

[0042] Figure 20 This is the admittance-frequency curve of an existing vertical electric field exciter acoustic resonator device (with a single-layer piezoelectric layer and a dielectric layer).

[0043] Figure 21This is the admittance-frequency curve of the seventh type of vertical electric field exciter acoustic resonator (the piezoelectric layer is a single-layer structure).

[0044] Figure 22 This is a real part curve of the conductivity-frequency of an existing vertical electric field exciter acoustic resonator (with a double-layer piezoelectric layer and no diamond film).

[0045] Figure 23 This is the conductance-frequency real part curve of the first type of vertical electric field exciter acoustic resonator (the piezoelectric layer has a double-layer structure and the lower surface of the diamond film has an annular groove).

[0046] In the figure: 100, substrate; 200, bottom electrode; 300, piezoelectric layer; 310, lower piezoelectric layer; 320, upper piezoelectric layer; 321, channel; 322, protrusion; 400, top electrode; 500, diamond film; 510, annular via; 520, annular groove; 530, central groove; 600, dielectric layer; 700, Bragg reflector layer. Detailed Implementation

[0047] The present invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention, and therefore only show the components relevant to the invention.

[0048] Example 1

[0049] like Figures 1-5 As shown, a vertical electric field exciter acoustic resonator includes a bottom electrode 200, a piezoelectric layer 300, a top electrode 400, and a diamond film 500. The bottom electrode 200, piezoelectric layer 300, and top electrode 400 are stacked sequentially from bottom to top. The diamond film 500 is disposed on the lower surface of the bottom electrode 200 and the piezoelectric layer 300. The piezoelectric layer 300 has a double-layer structure (e.g., ...). Figure 1 and Figure 2 (as shown) or a single-layer structure (such as) Figure 4 and Figure 5 (As shown).

[0050] A diamond film 500 is disposed on the lower surface of the bottom electrode 200 and the piezoelectric layer 300. Utilizing the ultra-high volume acoustic velocity characteristics of diamond, the diamond film 500 acts as a high acoustic velocity layer, introducing a high acoustic impedance difference boundary below the bottom electrode 200. This alters the acoustic boundary conditions in the vertical direction, causing the target SH2 mode frequency to shift upward. This effectively suppresses high-order parasitic modes outside the band and significantly reduces transverse stray waves within the band, achieving a clean response within the operating bandwidth. Simultaneously, the diamond film 500 reduces acoustic energy leakage towards the substrate 100 and enhances the localization of high-frequency acoustic waves within the piezoelectric layer 300 (double-layer structure). This allows for the resonant frequency to be increased to higher frequencies (such as 6G / 7G bands) while simultaneously improving the device's quality factor (Q value). Leveraging the high thermal conductivity of diamond, the diamond film 500 serves as a highly efficient heat dissipation layer, rapidly dissipating Joule heat generated by the high-frequency vibrations of the piezoelectric layer 300 (double-layer structure). This reduces the risks of temperature rise, frequency drift, and thermal failure, thereby comprehensively improving the device's operational stability and power tolerance under high-power conditions. Simultaneously, the diamond film 500 also acts as an etching barrier layer during the back-side etching process, reducing the risk of damage to the bottom electrode 200 and the piezoelectric layer 300 during back-side etching. This helps maintain the integrity of the suspended acoustic cavity structure, thus improving the device's wafer-level consistency and yield. Furthermore, due to the high rigidity of diamond, the diamond film 500 serves as a high-rigidity support layer, providing excellent mechanical support strength for the bottom electrode 200 and playing a role in stress release and balancing between heterogeneous integrated films, thereby greatly optimizing the device's resistance to mechanical shock.

[0051] Specifically, the bottom electrode 200 is preferably a planar electrode. The piezoelectric layer 300 is made of a piezoelectric material, including at least one of lithium tantalate (LiTaO3) and lithium niobate (LiNbO3). The top electrode 400 is preferably a comb-shaped electrode, including busbars and electrode fingers. The bottom electrode 200 and the top electrode 400 are made of a metallic material, including at least one of copper (Cu), aluminum (Al), and molybdenum (Mo), or an alloy containing at least one of these materials.

[0052] When the piezoelectric layer 300 adopts a double-layer structure, the thickness of the diamond film 500 is 3 nm to 50 nm, and the ratio of the thickness of the diamond film 500 to the thickness of the piezoelectric layer 300 is 0.006 to 0.10. Preferably, the thickness of the diamond film 500 is 5 nm to 30 nm, and the ratio of the thickness of the diamond film 500 to the thickness of the piezoelectric layer 300 is 0.01 to 0.06. More preferably, the thickness of the diamond film 500 is 10 nm to 25 nm, and the ratio of the thickness of the diamond film 500 to the thickness of the piezoelectric layer 300 is 0.02 to 0.05.

[0053] The design of the thickness of the diamond film 500 and its ratio to the thickness of the piezoelectric layer 300 allows the diamond film 500 to improve the equivalent stiffness and acoustic boundary constraint capability of the composite diaphragm without significantly damaging the target shear horizontal modal stress distribution and electromechanical coupling characteristics of the piezoelectric layer 300. This further achieves improved resonant frequency, suppression of out-of-band parasitic modes, reduction of in-band lateral parasitics, enhanced structural support, and improved thermal stability and power tolerance.

[0054] In a feasible embodiment, such as Figure 1 and Figure 2 As shown, when the piezoelectric layer 300 adopts a double-layer structure, it includes a lower piezoelectric layer 310 and an upper piezoelectric layer 320 stacked together. The upper surface of the upper piezoelectric layer 320 is etched with a plurality of channels 321, forming a plurality of protrusions 322. The protrusions 322 correspond to the electrode fingers in the top electrode 400. Specifically, the protrusions 322 are vertically arranged near the sidewalls of the channels 321.

[0055] In another feasible embodiment, such as Figure 3 As shown, the protrusion 322 is inclined near the side wall of the channel 321.

[0056] In one specific embodiment, both the bottom electrode 200 and the top electrode 400 are made of aluminum with a thickness of 50 nm; both piezoelectric layers 300 are made of lithium niobate with a thickness of 250 nm, the Euler angles of the lower piezoelectric layer 310 are (90°, -90°, -37°), and the Euler angles of the upper piezoelectric layer 320 are (90°, 90°, 23°); the diamond film 500 has a thickness of 10 nm and is disposed on the lower surface of the bottom electrode 200 and the piezoelectric layer 300. As a comparative example, the difference from the above specific embodiment is that the diamond film 500 is not disposed.

[0057] from Figure 18 and Figure 19 As can be seen, this specific embodiment can achieve a higher frequency compared to the comparative example.

[0058] In a feasible embodiment, such as Figure 6 and Figure 7 As shown, a substrate 100 is disposed on the lower surface of the entire vertical electric field exciter acoustic resonator device, that is, the entire vertical electric field exciter acoustic resonator device is stacked on the substrate 100.

[0059] Specifically, the substrate 100 has a cavity structure (not shown in the figure), and the substrate 100 is preferably made of any one or a combination of silicon (Si), silicon carbide (SiC) (such as 4H-SiC, 6H-SiC or 3C-SiC), boron nitride (BN), diamond or sapphire, and the substrate 100 may have high resistance (high resistivity, non-conductive).

[0060] The diamond film 500 is not only placed in the suspension area (i.e., above the cavity), but can also extend to the device anchor point or the connection area of ​​the substrate 100.

[0061] In another feasible embodiment, such as Figure 8 and Figure 9 As shown, a dielectric layer 600 is disposed on the upper surface of the substrate 100, that is, a dielectric layer 600 is disposed between the substrate 100 and the diamond film 500.

[0062] Specifically, the thickness of the dielectric layer 600 can be selected and set according to the vibration requirements of the device and the electromechanical coupling coefficient. The material of the dielectric layer 600 includes, but is not limited to, silicon oxide (SiO2). When the dielectric layer 600 is silicon oxide, it has a temperature compensation effect.

[0063] As a comparative example, such as Figure 10 As shown, the piezoelectric layer 300 adopts a single-layer structure and does not have a diamond film 500.

[0064] from Figure 20 and Figure 21 As can be seen, compared with the comparative example, this embodiment can effectively suppress parasitic modes and achieve higher frequencies.

[0065] In another feasible embodiment, such as Figure 11 and Figure 12 As shown, a Bragg reflector layer 700 is disposed between the substrate 100 and the dielectric layer 600, which forms a Bragg reflection effect for the downward propagating sound waves, thereby suppressing downward energy leakage and further improving the quality factor and electromechanical coupling coefficient of the resonator.

[0066] Specifically, the Bragg reflector layer 700 preferably has a multilayer stacked film structure, such as being formed by alternating stacks of high acoustic impedance materials and low acoustic impedance materials, wherein the high acoustic impedance materials include, but are not limited to, tungsten (W), hafnium oxide (HfO2), molybdenum (Mo), etc., and the low acoustic impedance materials include, but are not limited to, silicon oxide, etc.

[0067] In some embodiments, the diamond film 500 can be locally patterned to alter the lateral propagation path, thereby reflecting, discharging, or suppressing the lateral parasitic waveform, effectively suppressing lateral parasitic modes. Simultaneously, lateral modal modulation can be achieved through the acoustic pattern of the diamond film 500.

[0068] In a feasible embodiment, such as Figure 13 As shown, an annular through-hole 510 is formed on the diamond film 500, and the annular through-hole 510 penetrates the diamond film 500 in a vertical direction.

[0069] from Figure 13As can be seen, the annular through hole 510 is set at the circumferential edge of the bottom electrode 200, separating the diamond film 500 on the lower surface of the bottom electrode 200 from the diamond film 500 on the lower surface of the piezoelectric layer 300.

[0070] In another feasible embodiment, such as Figure 14 As shown, an annular groove 520 is formed on the lower surface of the diamond film 500.

[0071] from Figure 14 It can be seen that the annular groove 520 is set on the circumferential edge of the bottom electrode 200, but does not penetrate the diamond film 500, so that the thickness of the diamond film 500 at the center of the lower surface of the bottom electrode 200 is greater than the thickness of the diamond film 500 at the circumferential edge of the lower surface of the bottom electrode 200.

[0072] from Figure 22 and Figure 23 It can be seen that the patterned diamond film 500 can further effectively suppress lateral parasitic modes.

[0073] In other feasible embodiments, such as Figure 15 As shown, a central groove 530 is formed at the center of the lower surface of the diamond film 500.

[0074] from Figure 15 It can be seen that the central groove 530 does not penetrate the diamond film 500, which makes the thickness of the diamond film 500 at the center of the lower surface of the bottom electrode 200 less than the thickness of the diamond film 500 at the circumferential edge of the lower surface of the bottom electrode 200.

[0075] It should be noted that this application employs a piezoelectric layer 300 with optimized configuration of opposite polarization directions, crystal orientation flipping, and / or in-plane rotation angles (e.g., Figure 1As shown in the diagram, the piezoelectric layer 300, under vertical electric field excitation, forms an equivalent piezoelectric response more suitable for the excitation of higher-order modes at the target shear level. Through the aforementioned piezoelectric layer 300 (double-layer structure), the piezoelectric driving effect of the piezoelectric layer 300 can form coherent enhancement on the target SH2 mode, thereby improving the excitation efficiency of the target SH2 mode and contributing to increasing the target resonant frequency of the device. During operation, the polarization direction, crystal orientation, and / or in-plane rotation angle of the lower piezoelectric layer 310 and the upper piezoelectric layer 320 are different, thus modulating the phase of the equivalent piezoelectric response of the piezoelectric layer 300. When a vertical electric field is applied to the piezoelectric layer 300, the stress distribution of the target SH2 mode in the lower piezoelectric layer 310 and the upper piezoelectric layer 320 can match the equivalent piezoelectric response of the piezoelectric layer 300, allowing the piezoelectric driving effect generated by the piezoelectric layer 300 to be effectively superimposed on the target mode. However, for some non-target parasitic modes, since their stress distribution is difficult to effectively match with the polarization direction, crystal orientation, and / or rotation angle of the piezoelectric layer 300, their excitation efficiency is correspondingly reduced. Thus, the piezoelectric layer 300 of this application can achieve the comprehensive effects of target mode enhancement, parasitic mode suppression, passband response purification, and resonant frequency enhancement while maintaining high electromechanical coupling capability.

[0076] The acoustic filter based on the vertical electric field exciter loaded with diamond film 500 uses the thickness of diamond film 500 as a third frequency modulation variable. For example, by adjusting the thickness ratio of bottom electrode 200, piezoelectric layer 300, top electrode 400 and diamond film 500, the series resonator and parallel resonator can fall into the target frequency band of the filter respectively.

[0077] Example 2

[0078] The difference between this embodiment and Embodiment 1 lies in the placement of the diamond film 500. In this embodiment, the diamond film 500 is disposed between the upper and lower layers of the piezoelectric layer 300, specifically between the lower piezoelectric layer 310 and the upper piezoelectric layer 320. Figure 16 As shown.

[0079] A diamond film 500 is disposed between the upper and lower layers in the piezoelectric layer 300 to adjust the stress phase, acoustic impedance and modal distribution between the lower piezoelectric layer 310 and the upper piezoelectric layer 320, so that the target SH2 mode still satisfies the antisymmetric stress enhancement condition between the upper and lower layers, while weakening the parasitic modes that do not satisfy the phase matching condition.

[0080] Specifically, the thickness of the diamond film 500 is 1 nm to 20 nm. Preferably, the thickness of the diamond film 500 is 3 nm to 10 nm. More preferably, the thickness of the diamond film 500 is 4 nm to 7 nm.

[0081] This embodiment uses a thin diamond film 500 to avoid affecting the electric field distribution and the continuity of stress between the upper and lower layers.

[0082] In some embodiments, the diamond film 500 is locally patterned to effectively suppress lateral parasitic modes. The local patterning can be an annular through-hole 510, an annular groove 520, or a central groove 530.

[0083] Example 3

[0084] The difference between this embodiment and Embodiment 1 lies in the placement of the diamond film 500. In this embodiment, the diamond film 500 is disposed between the top electrode 400 and the piezoelectric layer 300, such as... Figure 17 As shown.

[0085] A diamond film 500 is disposed between the top electrode 400 and the piezoelectric layer 300, so that the diamond film 500 serves as a high thermal conductivity insulating layer, a surface acoustic modulation layer and an electrode loading buffer layer, thereby reducing the loss or parasitic response caused by the top electrode 400 directly participating in the acoustic cavity, and at the same time rapidly dissipating the heat generated by the top electrode 400.

[0086] Specifically, the piezoelectric layer 300 can be a double-layer structure or a single-layer structure. When the piezoelectric layer 300 is a double-layer structure, the thickness of the diamond film 500 is 1 nm to 15 nm. Preferably, the thickness of the diamond film 500 is 3 nm to 10 nm. More preferably, the thickness of the diamond film 500 is 3 nm to 7 nm.

[0087] In this embodiment, a thin diamond film 500 is used to avoid affecting the electric field entering the piezoelectric layer 300.

[0088] In some embodiments, the diamond film 500 is locally patterned to effectively suppress lateral parasitic modes.

[0089] Example 4

[0090] The difference between this embodiment and Embodiments 1, 2, and 3 is that the diamond film 500 is not set alone, but in combination. For example, the diamond film 500 is simultaneously set on the lower surface of the bottom electrode 200 and the piezoelectric layer 300, and between the upper and lower layers of the piezoelectric layer 300, or simultaneously set on the lower surface of the bottom electrode 200 and the piezoelectric layer 300, and between the top electrode 400 and the piezoelectric layer 300, or simultaneously set on the lower surface of the bottom electrode 200 and the piezoelectric layer 300, between the upper and lower layers of the piezoelectric layer 300, and between the top electrode 400 and the piezoelectric layer 300.

[0091] Based on the above-described preferred embodiments of the present invention, and through the foregoing description, those skilled in the art can make various changes and modifications without departing from the inventive concept. The technical scope of this invention is not limited to the contents of the specification, but must be determined according to the scope of the claims.

Claims

1. A vertical electric field exciter acoustic resonator device, comprising a bottom electrode (200), a piezoelectric layer (300), and a top electrode (400) stacked sequentially from bottom to top, wherein the piezoelectric layer (300) is a double-layer structure or a single-layer structure, characterized in that: It also includes a diamond film (500). When the piezoelectric layer (300) adopts a double-layer structure, the diamond film (500) is disposed on the lower surface of the bottom electrode (200) and the piezoelectric layer (300), and / or disposed between the top electrode (400) and the piezoelectric layer (300), and / or disposed between the upper and lower layers of the piezoelectric layer (300); when the piezoelectric layer (300) adopts a single-layer structure, the diamond film (500) is disposed on the lower surface of the bottom electrode (200) and the piezoelectric layer (300), and / or disposed between the top electrode (400) and the piezoelectric layer (300).

2. The vertical electric field exciter acoustic resonator device according to claim 1, characterized in that: An annular through-hole (510) is formed on the diamond film (500), and the annular through-hole (510) penetrates the diamond film (500) in a vertical direction.

3. The vertical electric field exciter acoustic resonator device according to claim 1, characterized in that: The lower surface of the diamond film (500) has an annular groove (520).

4. The vertical electric field exciter acoustic resonator device according to claim 1, characterized in that: A central groove (530) is formed at the center of the lower surface of the diamond film (500).

5. The vertical electric field exciter acoustic resonator device according to claim 1, characterized in that: It also includes a substrate (100) disposed on the lower surface of the entire vertical electric field exciter acoustic resonator.

6. The vertical electric field exciter acoustic resonator device according to claim 5, characterized in that: It also includes a dielectric layer (600) disposed on the upper surface of the substrate (100).

7. The vertical electric field exciter acoustic resonator device according to claim 6, characterized in that: It also includes a Bragg reflector layer (700) disposed between the substrate (100) and the dielectric layer (600).

8. The vertical electric field exciter acoustic resonator device according to claim 1, characterized in that: When the piezoelectric layer (300) adopts a double-layer structure, and the diamond film (500) is disposed on the bottom electrode (200) and the lower surface of the piezoelectric layer (300), the thickness of the diamond film (500) is 3nm to 50nm, and the ratio of the thickness of the diamond film (500) to the thickness of the piezoelectric layer (300) is 0.006 to 0.

10.

9. The vertical electric field exciter acoustic resonator device according to claim 1, characterized in that: When the piezoelectric layer (300) adopts a double-layer structure, and the diamond film (500) is disposed between the upper and lower layers of the piezoelectric layer (300), the thickness of the diamond film (500) is 1nm to 20nm.

10. The vertical electric field exciter acoustic resonator device according to claim 1, characterized in that: When the piezoelectric layer (300) adopts a double-layer structure, and the diamond film (500) is disposed between the top electrode (400) and the piezoelectric layer (300), the thickness of the diamond film (500) is 1nm to 15nm.

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