Resonator and manufacturing method therefor

Abstract

The present application relates to a resonator and a manufacturing method therefor. The resonator comprises an interdigital transducer. The interdigital transducer comprises a busbar unit and an interdigital electrode unit. The busbar unit comprises two busbars opposite each other in a first direction. The interdigital electrode unit is located between the two adjacent busbars. In the first direction, a region between the two busbars is configured as a plurality of acoustic channels on the basis of the interdigital electrode unit. The portion of the interdigital electrode unit that is located in each acoustic channel forms an interdigital electrode group. Any two adjacent interdigital electrode groups have different structures. Resonant frequencies of fundamental modes in the plurality of acoustic channels are identical. The resonator has stable operating performance, and excitation positions and intensities of spurious waves generated during operation of the resonator are dispersed, such that the out-of-band rejection performance of the resonator is effectively improved. In addition, the structure of interdigital electrodes and the structure of the interdigital electrode groups in the resonator can be flexibly adjusted on the basis of actual requirements. The manufacturing steps of the manufacturing method are simple and can be easily implemented.

Description

A resonator and its fabrication method

[0001] This application claims priority to Chinese patent application No. 202411977467.1, filed with the China National Intellectual Property Administration on December 30, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the fields of integrated circuits and communication technology, and in particular to a resonator and its fabrication method. Background Technology

[0003] With the continuous development and advancement of mobile communication technology, the number of communication frequency bands is also steadily increasing. Especially driven by 5G technology, the number of existing communication frequency bands has exceeded 50. To adapt to this diverse range of communication standards, the demand for filters in 5G communication equipment has increased dramatically, undoubtedly bringing huge development opportunities to the filter market. Among numerous mobile communication terminals, surface acoustic wave (SAW) filters have become the mainstream choice due to their ability to effectively handle radio frequency signals at specific frequencies. With the continuous evolution of RF front-end module technology, the performance requirements for filters are constantly increasing, and the market is trending towards higher performance, smaller size, and more complex filter products.

[0004] However, several technical challenges remain in the field of surface acoustic wave (SAW) filters, including passband transverse mode spurious peaks, out-of-band noise suppression, bandwidth limitations, and insufficient power capacity. During the propagation of SAW waves, in addition to the primary operating modes, parasitic mode clutter may also be generated. This parasitic mode clutter degrades the overall performance of SAW devices. For example, in system applications, if the SAW filter used for receiving signals cannot effectively filter out interference signals, it will affect the quality of the receiving link. Conversely, if the SAW filter used for transmitting signals emits interference signals, it will interfere with other systems, leading to a degraded system performance.

[0005] Therefore, how to provide a resonator and its manufacturing method to suppress the parasitic mode clutter generated during the operation of the resonator has become an important technical problem that needs to be solved by those skilled in the art.

[0006] It should be noted that the above introduction to the technical background is only for the purpose of providing a clear and complete explanation of the technical solutions of this application and facilitating understanding by those skilled in the art. It should not be assumed that these technical solutions are known to those skilled in the art simply because they have been described in the background section of this application. Summary of the Invention

[0007] Therefore, it is necessary to provide a resonator and its manufacturing method to address the problem that parasitic mode clutter generated during the operation of the resonator affects the overall performance of the resonator in the existing technology.

[0008] To achieve the above and other related objectives, this application provides a resonator including an interdigital transducer, wherein the interdigital transducer includes:

[0009] A busbar unit includes at least two busbars, the two busbars being opposite each other in a first direction;

[0010] An interdigital electrode unit, located between two busbars, is configured as multiple acoustic channels in the region between the two busbars along the first direction, with the portion of the interdigital electrode unit located in each acoustic channel forming an interdigital electrode group; wherein...

[0011] Any two adjacent interdigital electrode groups have different structures, and the main modes in the multiple acoustic channels have the same resonant frequency.

[0012] In one embodiment, the interdigital electrode unit includes n first interdigital electrodes, which are arranged along a second direction, n>1, and the second direction intersects the first direction; each first interdigital electrode includes a plurality of interdigital electrode segments connected sequentially along the first direction, and the segmentation surface between any two adjacent interdigital electrode segments is parallel to the second direction. The plurality of segmentation surfaces that are flush in the first direction in the interdigital electrode unit constitute an interface, and the region between the two busbars is configured as a plurality of acoustic channels via the interface in the interdigital electrode unit.

[0013] In one embodiment, the structural differences between any two adjacent interdigitated electrode groups include at least one of the following: different widths of the interdigitated electrode segments, different spacing between two adjacent interdigitated electrode segments, different duty cycles of the interdigitated electrode groups, different electrode period lengths of the interdigitated electrode groups, and different relative film thicknesses of the interdigitated electrode groups.

[0014] In one embodiment, the main modes in the multiple acoustic channels have the same resonant frequency, which is achieved by coordinating the adjustment of the duty cycle of the interdigital electrode groups located in different acoustic channels and the electrode period length of the interdigital electrode groups.

[0015] In one embodiment, the interdigital electrode unit includes an adjacent i-th interdigital electrode group and an i+1-th interdigital electrode group, wherein the duty cycle of the i+1-th interdigital electrode group is greater than the duty cycle of the i-th interdigital electrode group, and the electrode period length of the i+1-th interdigital electrode group is less than the electrode period length of the i-th interdigital electrode group.

[0016] In one embodiment, each of the first interdigital electrodes includes an adjacent i-th interdigital electrode segment and an i+1-th interdigital electrode segment. Along the second direction, the distance between the central axis of the i-th interdigital electrode segment and the central axis of the i+1-th interdigital electrode segment in the n first interdigital electrodes first decreases and then increases.

[0017] In one embodiment, both the i-th interdigitated electrode segment and the (i+1)-th interdigitated electrode segment include a first edge and a second edge opposite to each other in the second direction, where i ≥ 1;

[0018] The interdigitated electrode unit includes a first edge interdigitated electrode and a second edge interdigitated electrode. In the second direction, the first edge interdigitated electrode and the second edge interdigitated electrode are respectively located at both ends of the interdigitated electrode unit. In the first edge interdigitated electrode, the first edge of the i-th interdigitated electrode segment is aligned with the first edge of the (i+1)-th interdigitated electrode segment. In the second edge interdigitated electrode, the second edge of the i-th interdigitated electrode segment is aligned with the second edge of the (i+1)-th interdigitated electrode segment.

[0019] In one embodiment, in the second direction, all the interdigitated electrode segments within any one of the interdigitated electrode groups have the same width, and within the same interdigitated electrode group, the spacing between any two adjacent interdigitated electrode segments is equal.

[0020] In one embodiment, the width of the i-th interdigital electrode segment is different from the width of the (i+1)-th interdigital electrode segment; in the interdigital electrode unit, any first interdigital electrode located between the first edge interdigital electrode and the second edge interdigital electrode satisfies the following: the distance between the first edge of the i-th interdigital electrode segment and the first edge of the (i+1)-th interdigital electrode segment increases as the distance between the first interdigital electrode and the first edge interdigital electrode increases, and the distance between the second edge of the i-th interdigital electrode segment and the second edge of the (i+1)-th interdigital electrode segment increases as the distance between the first interdigital electrode and the second edge interdigital electrode increases.

[0021] In one embodiment, the interdigital electrode unit further includes an m-th intermediate interdigital electrode, which is located between the first edge interdigital electrode and the second edge interdigital electrode, where 1 < m < n. In the m-th intermediate interdigital electrode, the offset distance between the i-th interdigital electrode segment and the (i+1)-th interdigital electrode segment is (m-1) × (A). i -A i+1 ) / (n-1), where A i A is the width of the i-th interdigital electrode segment of the m-th intermediate interdigital electrode. i+1The width of the (i+1)th interdigital electrode segment of the m-th intermediate interdigital electrode.

[0022] In one embodiment, at least one of the interdigital electrode groups includes a first interdigital electrode segment and a second interdigital electrode segment arranged alternately along the second direction, wherein the width of the first interdigital electrode segment is different from the width of the second interdigital electrode segment, and the spacing between any adjacent first interdigital electrode segments and second interdigital electrode segments is the same.

[0023] In one embodiment, the interdigital electrode unit further includes a plurality of second interdigital electrodes, which are arranged alternately with n first interdigital electrodes, or the plurality of second interdigital electrodes are arranged alternately with n first interdigital electrodes at intervals; the width of the portion of the second interdigital electrode located in any two adjacent interdigital electrode groups is the same.

[0024] In one embodiment, the resonator further includes two reflective gratings, which are arranged on both sides of the interdigital transducer in the second direction, and the gratings of the reflective gratings are at least one of a rectangular continuous structure and a segmented structure.

[0025] In one embodiment, the interdigital transducer further includes a plurality of dummy fingers located between any of the first interdigital electrodes and the busbars not connected to the first interdigital electrode, and the end of the dummy finger near the first interdigital electrode has a gap with the first interdigital electrode.

[0026] Secondly, this application also provides a method for manufacturing a resonator, the resonator including an interdigital transducer, the method comprising the following steps:

[0027] An interdigital transducer is formed, comprising a busbar unit and an interdigital electrode unit. The busbar unit includes at least two busbars facing each other in a first direction. The interdigital electrode unit is located between the two busbars. Along the first direction, the region between the two busbars is configured as multiple acoustic channels based on the interdigital electrode unit. The portion of the interdigital electrode unit located in each acoustic channel constitutes an interdigital electrode group.

[0028] Any two adjacent interdigital electrode groups have different structures, and the main modes in the multiple acoustic channels have the same resonant frequency.

[0029] As described above, the resonator of this application, through the design of the interdigital electrode unit structure, divides the area between two busbars into multiple acoustic channels, with the portion of the interdigital electrode unit located in each acoustic channel forming an interdigital electrode group. By adjusting and controlling the structure of multiple interdigital electrode groups, even when the structures of any two adjacent interdigital electrode groups are different, the resonant frequencies of the master modes excited by the interdigital electrode groups in multiple acoustic channels are the same, ensuring that the resonant frequency, anti-resonant frequency, and Q value of the resonator remain stable regardless of changes in the structure of the interdigital electrode units. Simultaneously, because the structures of any two adjacent interdigital electrode groups are different, the frequency positions of clutter excitation in different acoustic channels are different, thereby dispersing the clutter excitation position and intensity, and improving the out-of-band suppression performance of the resonator. Furthermore, while satisfying the out-of-band suppression performance of the resonator, the structure of the interdigital electrodes and the structure of the interdigital electrode groups in the resonator can be flexibly adjusted according to actual needs. The resonator fabrication method of this application can produce a resonator structure with improved out-of-band suppression performance, and the fabrication steps are simple and easy to implement. Attached Figure Description

[0030] Figure 1 shows a structural schematic diagram of a resonator provided in the comparative example of this application;

[0031] Figure 2 shows a frequency response curve of the resonator shown in Figure 1;

[0032] Figure 3 shows the frequency response curve at the clutter location in Figure 2;

[0033] Figure 4 shows the frequency response curve of the real part of the admittance at the clutter location in Figure 2.

[0034] Figure 5 shows a schematic diagram of a resonator provided in Embodiment 1 of this application;

[0035] Figure 6 shows a schematic diagram of an interdigital transducer in a resonator provided in Embodiment 1 of this application;

[0036] Figure 7 shows another structural schematic diagram of the interdigital transducer in the resonator provided in Embodiment 1 of this application;

[0037] Figure 8 shows a frequency response curve of a resonator provided in Embodiment 1 of this application;

[0038] Figure 9 shows the frequency response curve at the clutter location in Figure 8;

[0039] Figure 10 shows the frequency response curve of the real part of the admittance at the clutter location in Figure 8.

[0040] Figure 11 shows a partial structural schematic diagram of an interdigital transducer provided in Embodiment 1 of this application;

[0041] Figure 12 shows a comparison of the frequency response curves of the resonator provided in Embodiment 1 of this application and the resonator in the comparative example;

[0042] Figure 13 shows a partial enlarged view of the passband region in Figure 12;

[0043] Figure 14 shows a partial enlarged view of the left-side region of the passband in Figure 12;

[0044] Figure 15 shows a magnified view of the clutter generation location in Figure 14;

[0045] Figure 16 shows a partial structural schematic diagram of an interdigital transducer provided in Embodiment 2 of this application;

[0046] Figure 17 shows a schematic diagram of an interdigital transducer provided in Embodiment 3 of this application.

[0047] Explanation of reference numerals in the attached diagram: 1-Resonator, 10-Interdigital transducer, 101-Acoustic channel, 11-Busbar, 12-Interdigital electrode group, 12a-i-th interdigital electrode group, 12b-i+1-th interdigital electrode group, 120-First interdigital electrode, 120a-First edge interdigital electrode, 120b-Second edge interdigital electrode, 120c-m-th intermediate interdigital electrode, 1200-Interdigital electrode segment, 1201a / 1201b / 1201c-i-th interdigital electrode segment, 1202a / 1202b / 1202c-i+1-th interdigital electrode segment, 1203-First interdigital electrode segment, 1204-Second interdigital electrode segment, 121-Second interdigital electrode, 20-Reflection grating, 21-Grate bar. Detailed Implementation

[0048] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0049] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0050] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0051] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0052] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0053] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0054] Comparative Example

[0055] Please refer to Figure 1, which shows a schematic diagram of a resonator provided in this comparative example. The resonator includes an interdigital transducer 10, which includes two busbars 11 and a plurality of first interdigital electrodes 120. The two busbars 11 are opposite each other in a first direction Y. The plurality of first interdigital electrodes 120 are arranged at equal intervals between the two busbars 11. The plurality of first interdigital electrodes 120 are alternately connected to the two busbars 11. Each first interdigital electrode 120 has a gap between it and any unconnected busbar 11. The first interdigital electrodes 120 are rectangular, with a width of A, a spacing of B between any two adjacent first interdigital electrodes 120, and an electrode period length of C, where C = A + B. The duty cycle (or metallization) of the resonator is A / C.

[0056] Please refer to Figure 2, which shows a frequency response curve of the resonator. As can be seen from Figure 2, the resonant frequency is 913MHz (point m3 in Figure 2), and the anti-resonant frequency is 958MHz. The quality factor Q of the resonator is high at both the resonant and anti-resonant frequencies (reflected by the sharpness of the curves at the corresponding points). However, parasitic mode clutter associated with the main operating mode appears near 739MHz (point m4 in Figure 2). This clutter severely affects the out-of-band rejection performance of the filter, making the resonator unsuitable for practical applications. Please refer to Figures 3 and 4 in conjunction. Figure 3 shows the frequency response curve at the clutter location in Figure 2, where point m1 in Figure 3 corresponds to a magnified view of point m4 in Figure 2. Figure 4 shows the frequency response curve of the real part of the admittance at the clutter location in Figure 2, where point m2 corresponds to the real part of the admittance at point m4 in Figure 2.

[0057] Analysis of the parasitic mode clutter generated by the main operating mode reveals a correlation between the excitation intensity and frequency position of this clutter and the resonator's duty cycle and relative film thickness. For example, when the dominant mode is surface leakage acoustic wave (LSAW), Rayleigh mode clutter (RSAW) appears at a frequency 0.8 times lower than the dominant mode frequency. Based on this, embodiments of this application adjust the structure and distribution of the interdigitated electrodes in the resonator to effectively suppress clutter modes while maintaining stable dominant mode performance, thereby improving the resonator's out-of-band suppression performance.

[0058] Example 1

[0059] This embodiment provides a resonator 1. Please refer to Figure 5, which shows a schematic diagram of one structure of the resonator 1. The resonator 1 includes an interdigital transducer 10, which includes a busbar unit (not labeled) and an interdigital electrode unit (not labeled).

[0060] Specifically, the busbar unit includes at least two busbars 11, which are opposite each other in a first direction Y. The interdigital electrode unit is located between the two busbars 11. Along the first direction Y, the region between the two busbars 11 is configured as a plurality of acoustic channels 101 based on the interdigital electrode unit (as shown in FIG. 6). The portion of the interdigital electrode unit located in each acoustic channel 101 constitutes an interdigital electrode group 12 (as shown in FIG. 6). Any two adjacent interdigital electrode groups 12 have different structures, and the resonant frequencies of the dominant modes in the plurality of acoustic channels 101 are the same.

[0061] Specifically, the main structure of resonator 1 is designed based on the characteristics of the dominant mode, possessing specific frequency and phase characteristics, enabling the dominant mode to be excited and generated in the interdigital transducer 10 and remain relatively stable during propagation. Clutter, however, is usually parasitic and accompanies the dominant mode, exhibiting non-specificity and sensitivity to structural changes in the interdigital electrode units (e.g., electrode period length, duty cycle, etc.). These changes result in different phase differences during propagation, causing variations in the spatial superposition effect of clutter and thus dispersing the excitation location of the clutter. In this embodiment, the interdigital electrode units configure the area between the two busbars into multiple acoustic channels 101, with the portion of the interdigital electrode units located in each acoustic channel 101 constituting an interdigital electrode group 12. Furthermore, by setting any two adjacent interdigital electrode groups 12 to have different structures, the resonant frequencies of the main modes excited by the interdigital electrode groups 12 in multiple acoustic channels 101 are the same. Since the parasitic mode clutter generated with the main mode is usually different from the resonant frequency of the main mode, by adjusting the structures of at least two adjacent interdigital electrode groups 12 to be different, the clutter generated with the main mode in each acoustic channel 101 is excited at different frequency positions, thereby dispersing the position and intensity of clutter excitation in the entire resonator, reducing the intensity of clutter (especially the intensity of clutter near the resonant frequency of the main mode), and thus improving the out-of-band suppression performance of the resonator.

[0062] In some embodiments, the interdigital electrode unit includes n first interdigital electrodes 120. The n first interdigital electrodes 120 are arranged along a second direction X, where n > 1. The second direction X intersects the first direction Y (e.g., perpendicularly). Referring to FIG6, FIG6 shows a schematic structural diagram of the interdigital transducer 10 in the resonator 1. Each first interdigital electrode 120 includes a plurality of interdigital electrode segments 1200 connected sequentially along the first direction Y. The segmented surface between any two adjacent interdigital electrode segments 1200 is parallel to the second direction X. The plurality of segmented surfaces flush in the first direction Y in the interdigital electrode unit constitute an interface. The region between the two busbars 11 is configured as a plurality of acoustic channels 101 via the interface in the interdigital electrode unit. Each first interdigital electrode 120 includes a plurality of interdigital electrode segments 1200 sequentially connected along the first direction Y. This means that each first interdigital electrode 120 includes two or more interdigital electrode segments 1200 (as shown in Figure 6) (as shown in Figure 7). The specific number of interdigital electrode segments 1200 included in the first interdigital electrode 120 is selected based on actual needs. Please refer to Figure 7, which shows another structural schematic diagram of the interdigital transducer 10 in the resonator 1.

[0063] In this first embodiment, the first interdigital electrode 120 is designed as a segmented structure (i.e., each first interdigital electrode 120 includes interdigital electrode segments 1200 connected sequentially along the first direction Y). The segmented surface between any two adjacent interdigital electrode segments 1200 of the first interdigital electrode 120 is parallel to the second direction X. Therefore, the interdigital electrode unit naturally includes multiple segmented surfaces, and different segmented surfaces of different first interdigital electrodes 120 are sequentially kept flush, so that the segmented surfaces flush in the first direction Y in the interdigital electrode unit constitute an interface. When the first interdigital electrode 120 has a two-segment structure, the first interdigital electrode 120 has only one segmented surface, and the interfaces of multiple first interdigital electrodes 120 are kept flush in the first direction Y to form an interface. This interface configures the area between the two busbars 11 as two acoustic channels 101 (the interface and a busbar 11 constitute an acoustic channel 101). When the first interdigital electrode 120 has a three-segment structure, it has two segmented surfaces (e.g., a first segmented surface and a second segmented surface). The first segmented surfaces of multiple first interdigital electrodes 120 are aligned in the first direction Y to form a first interface, and the second segmented surfaces of multiple first interdigital electrodes 120 are aligned in the first direction Y to form a second interface. These two interfaces configure the area between the two busbars 11 as three acoustic channels 101. It is easy to understand that each first interdigital electrode 120 in the interdigital electrode unit has an interdigital electrode segment 1200 located in the same acoustic channel 101. Therefore, multiple interdigital electrode segments 1200 exist in the same acoustic channel 101, and these interdigital electrode segments 1200 together constitute an interdigital electrode group 12.

[0064] Please refer to Figure 8, which shows a frequency response curve of the resonator 1 provided in an embodiment of this application. As can be seen from Figure 8, the resonant frequency of the resonator 1 is 913MHz (at point m3 in Figure 8), and the anti-resonant frequency of the resonator 1 is 958MHz. That is, although the structure of the first interdigital electrode 120 in the resonator is changed from a rectangular continuous structure to a segmented structure, by controlling and adjusting the structure of the interdigital electrode group 12 located in each acoustic channel 101, it can be ensured that the resonant frequency, anti-resonant frequency, and Q value at the resonant frequency and the Q value at the anti-resonant frequency of the resonator 1 remain basically unchanged, thus ensuring the working performance of the resonator 1.

[0065] Furthermore, comparing Figures 2 and 8, although parasitic mode clutter still appears near 739MHz (as shown at point m4 in Figure 8), comparing Figures 3 and 9, and Figures 4 and 10, it can be seen that this clutter is effectively suppressed (based on the height of the clutter peak). Figure 9 shows the frequency response curve at the clutter location in Figure 8, and Figure 10 shows the frequency response curve of the real part of the admittance at the clutter location in Figure 8. Therefore, by reasonably adjusting the width, spacing, and electrode period length of the interdigital electrode segments 1200 in different interdigital electrode groups 12, the resonant frequency, anti-resonant frequency, and Q value at the resonant and anti-resonant frequencies of the resonator 1 remain almost unchanged, and the parasitic mode clutter generated by the dominant mode can be effectively suppressed.

[0066] In some embodiments, structural differences between any two adjacent interdigitated electrode groups 12 include at least one of the following: different widths of the interdigitated electrode segments 1200, different spacing between two adjacent interdigitated electrode segments 1200, different duty cycles of the interdigitated electrode groups 12, different electrode period lengths of the interdigitated electrode groups 12, and different relative film thicknesses of the interdigitated electrode groups 12. Wherein, the width of the interdigitated electrode segment 1200 refers to the width of the interdigitated electrode segment 1200 in the second direction X. The electrode period length of the interdigitated electrode group 12 refers to the sum of the width of the interdigitated electrode segment 1200 and the spacing between two adjacent interdigitated electrode segments 1200. The duty cycle of the interdigitated electrode group 12 refers to the ratio of the width of the interdigitated electrode segment 1200 in the interdigitated electrode group 12 to the electrode period length of the interdigitated electrode group 12. The relative film thickness of the interdigitated electrode group 12 refers to the ratio of the thickness of the interdigitated electrode group to the wavelength of the resonator (twice the electrode period length). It should be noted that the different structural parameters mentioned above refer to the different corresponding structural parameters of any two adjacent interdigital electrode groups, rather than the different corresponding structural parameters in the same interdigital electrode group. For example, the different widths of the interdigital electrode segments 1200 mean that the width of the interdigital electrode segments 1200 in one interdigital electrode group 12 is different from the width of the interdigital electrode segments 1200 in another interdigital electrode group 12.

[0067] Specifically, the dominant mode frequency of a surface acoustic wave (SAW) resonator is typically influenced by multiple structural parameters of the interdigital transducer. These parameters include the electrode period length, the width of the interdigital electrodes, the spacing between adjacent interdigital electrodes, the thickness of the piezoelectric layer, the thickness of the electrode layer (including the interdigital electrode units), and the duty cycle. Therefore, by controlling one or more of the aforementioned structural parameters of the interdigital electrode segments 1200 in any two adjacent interdigital electrode groups 12 to be different, it is possible to ensure that the resonant frequencies of the dominant modes in multiple acoustic channels 101 are the same even when the structures of the interdigital electrode groups 12 in the acoustic channels 101 are different. This effectively suppresses clutter without affecting the dominant mode and weakening the resonator's performance.

[0068] In some embodiments, the resonant frequencies of the master modes in the plurality of acoustic channels 101 are the same, which is achieved by coordinating the adjustment of the duty cycle of the interdigital electrode groups 12 located in different acoustic channels 101 and the electrode period length of the interdigital electrode groups 12.

[0069] In some embodiments, please refer to FIG11. FIG11 shows a partial structural schematic diagram of an interdigital transducer 10 provided in an embodiment of this application. The interdigital electrode unit includes an adjacent i-th interdigital electrode group 12a and an (i+1)-th interdigital electrode group 12b, wherein the duty cycle A of the (i+1)-th interdigital electrode group 12b is... i+1 / C i+1 The duty cycle A is greater than that of the i-th interdigital electrode group 12a. i / C i And the electrode period length C of the (i+1)th interdigital electrode group 12b i+1 The electrode period length C is less than that of the i-th interdigital electrode group 12a. i .

[0070] It should be noted that, in this embodiment, Figure 11 uses the two-segment interdigitated electrode shown in Figure 6 as an example. In actual application, when the first interdigitated electrode 120 is divided into three or more segments, the structure of the i-th interdigitated electrode group 12a and the (i+1)-th interdigitated electrode group 12b is not as shown in Figure 11. Since one end of the multiple first interdigitated electrodes 120 is alternately connected to the two busbars 11, in the multiple interdigitated electrode groups 12 obtained by division, the ends of the multiple interdigitated electrode segments 1200 in the two interdigitated electrode groups 12 closest to the two busbars 11 are staggered, and the two ends of the multiple interdigitated electrode segments 1200 in the remaining interdigitated electrode groups 12 are kept flush (as shown in the structure of the interdigitated electrode group in the middle electrical channel in Figure 7).

[0071] In this first embodiment, the dominant mode frequency of a surface acoustic wave (SAW) resonator is typically determined by multiple structural parameters. Among these, the duty cycle and electrode period length are two key parameters. The duty cycle characterizes the proportion of time the sound wave is excited within one cycle; the electrode period length, the distance between two interdigitated electrodes, characterizes the path length of the sound wave propagation. Thus, both the duty cycle and the electrode period length influence the resonance conditions of the sound wave. An increase in the duty cycle means an increase in the sound wave excitation time, while a decrease in the electrode period length means a shorter sound wave propagation path. These changes in duty cycle and electrode period length can compensate for each other to ensure that the resonance conditions of the sound wave remain unchanged, thereby maintaining a consistent dominant mode frequency. Since the propagation of sound waves in a resonator is affected not only by time and space, but also by material properties, sound wave propagation speed, and phase matching, the combined effect of these factors results in a non-simple linear relationship between the duty cycle and electrode period length on the resonant frequency. Therefore, in practical applications, the duty cycle and electrode period length of the interdigitated electrode groups 12 in different sound channels 101 can be adjusted in opposite directions to achieve the same resonant frequency for the main mode in multiple sound channels 101.

[0072] In some embodiments, as shown in FIG11, each of the first interdigital electrodes 120 includes an adjacent i-th interdigital electrode segment and an (i+1)-th interdigital electrode segment. For example, the i-th interdigital electrode segment may be located in the i-th interdigital electrode group 12a, and the (i+1)-th interdigital electrode segment may be located in the (i+1)-th interdigital electrode group 12b. Along the second direction X, the distance D between the central axis I of the i-th interdigital electrode segment and the central axis II of the (i+1)-th interdigital electrode segment in the n first interdigital electrodes 120 first decreases and then increases.

[0073] In some embodiments, as shown in FIG11, the i-th interdigitated electrode segment and the (i+1)-th interdigitated electrode segment each include a first edge (unmarked) and a second edge (unmarked) opposite each other in the second direction X, where i ≥ 1. The n first interdigitated electrodes 120 include a first edge interdigitated electrode 120a and a second edge interdigitated electrode 120b. In the second direction X, the first edge interdigitated electrode 120a and the second edge interdigitated electrode 120b are respectively located at both ends of the interdigitated electrode unit. Specifically, in the first edge interdigitated electrode 120a: the first edge of the i-th interdigitated electrode segment 1201a is aligned with the first edge of the (i+1)-th interdigitated electrode segment 1202a. In the second edge interdigitated electrode 120b: the second edge of the i-th interdigitated electrode segment 1201b is aligned with the second edge of the (i+1)-th interdigitated electrode segment 1202b.

[0074] In some embodiments, in the second direction X, the width of all interdigital electrode segments 1200 within any interdigital electrode group 12 is equal, and the spacing between any two adjacent interdigital electrode segments 1200 within the same interdigital electrode group 12 is equal. That is, the width of all i-th interdigital electrode segments is consistent, and the width of all (i+1)-th interdigital electrode segments is consistent, which simplifies the overall structure of the interdigital electrode unit. The electrode period length C of the (i+1)-th interdigital electrode group 12b... i+1 The electrode period length C is less than that of the i-th interdigital electrode group 12a. i In the case where the spacing B of the interdigital electrode segments 1200 in the (i+1)th interdigital electrode group 12b is... i+1 The spacing B is smaller than that of the interdigital electrode segments 1200 in the i-th interdigital electrode group 12a. i .

[0075] In some embodiments, the width of the i-th interdigital electrode segment is different from the width of the (i+1)-th interdigital electrode segment; for example, the width of the i-th interdigital electrode segment is smaller than the width of the (i+1)-th interdigital electrode segment. In the interdigital electrode unit, any first interdigital electrode 120 located between the first edge interdigital electrode 120a and the second edge interdigital electrode 120b satisfies the following: the distance D1 between the first edge of the i-th interdigital electrode segment and the first edge of the (i+1)-th interdigital electrode segment increases as the distance between the first interdigital electrode 120 and the first edge interdigital electrode 120a increases. Furthermore, the distance D2 between the second edge of the i-th interdigital electrode segment and the second edge of the (i+1)-th interdigital electrode segment increases as the distance between the first interdigital electrode 120 and the second edge interdigital electrode 120b increases.

[0076] In this first embodiment, by controlling the structure and arrangement of the first interdigital electrodes 120 in the interdigital electrode unit, in the second direction X, among the n first interdigital electrodes 120 located at the outermost edges (i.e., the first edge interdigital electrode 120a and the second edge interdigital electrode 120b), the i-th interdigital electrode segment 1201a of the first edge interdigital electrode 120a is aligned with the first edge 1202a of the (i+1)-th interdigital electrode segment, and the i-th interdigital electrode segment 1201b of the second edge interdigital electrode 120b is aligned with the first edge 1202a of the (i+1)-th interdigital electrode segment. The second edges of the finger electrode segments 1202b are aligned, and the offset distance between the i-th interdigital electrode segment and the (i+1)-th interdigital electrode segment of any first interdigital electrode 120 increases as the distance between the first interdigital electrode 120 and the first edge interdigital electrode 120a (or between the second edge interdigital electrode 120b) increases. This causes the i-th interdigital electrode segment in the first interdigital electrode 120 to gradually shift relative to the (i+1)-th interdigital electrode segment along the arrangement direction of the plurality of first interdigital electrodes 120 (i.e., the second direction X), enabling the electrode period length C of the i-th interdigital electrode group 12a in the interdigital electrode unit to be... i The electrode period length C is greater than that of the (i+1)th interdigital electrode group 12b. i+1 Furthermore, the duty cycle of the i-th interdigital electrode group 12a is less than that of the (i+1)-th interdigital electrode group 12b, thereby achieving the same resonant frequency of the main mode excited by the i-th interdigital electrode group 12a and the (i+1)-th interdigital electrode group 12b, and effectively suppressing clutter dispersion.

[0077] In some embodiments, the interdigitated electrode unit further includes an m-th intermediate interdigitated electrode 120c, which is located between the first edge interdigitated electrode 120a and the second edge interdigitated electrode 120b, where 1 < m < n. In the m-th intermediate interdigitated electrode 120c, the offset distance between the i-th interdigitated electrode segment 1201c and the (i+1)-th interdigitated electrode segment 1202c is (m-1) × (A). i -A i+1 ) / (n-1), where A i A is the width of the i-th interdigital electrode segment 1201c of the m-th intermediate interdigital electrode 120c. i+1 This refers to the width of the (i+1)th interdigital electrode segment 1202c of the m-th intermediate interdigital electrode 120c. In other words, the interdigital electrode segments 1200 in the interdigital electrode groups 12 of the multiple acoustic channels 101 are arranged at equal intervals, which helps to ensure the consistency of the electrode period length of the interdigital electrode groups 12, and thus facilitates the control of the consistency of the main mode frequency.

[0078] In some embodiments, the lengths L of the plurality of acoustic channels 101 in the first direction Y may be the same (as shown in Figures 6 and 7) or different, depending on actual needs.

[0079] In some embodiments, the interdigital transducer further includes a plurality of dummy fingers (not shown) located between any of the first interdigital electrodes 120 and the busbar 11 to which the first interdigital electrode 120 is not connected, with a gap between the end of the dummy finger approaching the first interdigital electrode 120 and the first interdigital electrode 120. The arrangement of the dummy fingers can suppress unwanted lateral modes, thereby improving the operating performance of the resonator.

[0080] In some embodiments, as shown in FIG5, the resonator 1 further includes two reflective gratings 20, which are arranged on both sides of the interdigital transducer 10 in the second direction X. The gratings 21 of the reflective gratings 20 have at least one of a rectangular continuous structure (refer to FIG1) and a segmented structure. When the gratings 21 of the reflective gratings 20 have a segmented structure, the number of segments of the gratings 21 can be the same as the number of interdigital electrode segments 1200 included in the first interdigital electrode 120, and the structure and arrangement of the plurality of gratings 21 in the reflective gratings 20 are consistent with the structure and arrangement of the plurality of first interdigital electrodes 120 in the interdigital transducer 10.

[0081] In some embodiments, the resonator 1 further includes a piezoelectric material layer (not shown), and the interdigital transducer 10 is located above the piezoelectric material layer. The material of the piezoelectric material layer includes at least one of YX lithium tantalate and YX lithium niobate. Specifically, the YX lithium tantalate propagates in a Y-cut X-propagation manner, with a shear angle ranging from 30° to 60° (inclusive). The YX lithium niobate also propagates in a Y-cut X-propagation manner, with a shear angle ranging from 30° to 60° (inclusive). In other embodiments, the piezoelectric material layer may also include other suitable piezoelectric materials.

[0082] Please refer to Figures 12 to 14. Figure 12 shows a comparison of the frequency response curves of the resonator provided in this embodiment and the resonator in the comparative example. Figure 13 shows a partial enlarged view of the passband region in Figure 12, and Figure 14 shows a partial enlarged view of the left side of the passband region in Figure 12. The dashed curve represents the response curve of the resonator provided in the comparative example, and the solid curve represents the response curve of the resonator in this embodiment. As can be seen from Figure 13, the amplitudes of the frequency response curves of the two resonators in the passband region are essentially the same, and the response curves largely overlap. This indicates that in this embodiment, based on the interdigital electrode unit, the region between the two busbars 11 is configured as multiple acoustic channels 101, and the structure of the interdigital electrode groups 12 located in different acoustic channels 101 is adjusted so that the structures of any two adjacent interdigital electrode groups 12 are different, but the resonant frequencies of the main modes of different acoustic channels are the same, without deteriorating the insertion loss performance of the resonator (i.e., the normal operating performance of the resonator remains stable).

[0083] Please refer to Figure 15, which shows a magnified view of the clutter generation location in Figure 14. As can be seen from Figure 15, the clutter of the comparative resonator (point m1 in Figure 15) is generated at 752 MHz with an insertion loss of -34.226 dB. The clutter of the resonator provided in this embodiment (point m2 in Figure 15) is generated at 751 MHz with an insertion loss of -40.593 dB. This means that although the structural adjustment of the interdigitated electrode unit in this embodiment does not change the clutter generation location, it can effectively suppress the clutter intensity. For example, it improves the clutter intensity by 6 dB near 750 MHz. This also indicates that the resonator in this embodiment also performs well in terms of left-side passband suppression, helping to ensure the resonator's out-of-band signal suppression performance.

[0084] The resonator in this embodiment divides the area between two busbars into multiple acoustic channels by designing the structure of the interdigital electrode unit. The portion of the interdigital electrode unit located in each acoustic channel constitutes an interdigital electrode group. By adjusting and controlling the structure of multiple interdigital electrode groups, even when the structures of any two adjacent interdigital electrode groups are different, the resonant frequencies of the master modes excited by the interdigital electrode groups in multiple acoustic channels are the same. This ensures that the resonant frequency, anti-resonant frequency, and Q value of the resonator remain stable regardless of changes in the structure of the interdigital electrodes. Simultaneously, because the structures of any two adjacent interdigital electrode groups are different (e.g., different duty cycles, different electrode period lengths), the frequency positions of clutter excitation in different acoustic channels are different, thereby dispersing the location and intensity of clutter excitation and improving the out-of-band suppression performance of the resonator.

[0085] Example 2

[0086] This second embodiment provides a resonator. The main difference between this second embodiment and the first embodiment is that in the resonator of the first embodiment, the width of all the interdigitated electrode segments in any acoustic channel is the same, while in the resonator of this second embodiment, the width of the interdigitated electrode segments in some acoustic channels is not entirely the same. Please refer to Figure 5. The resonator includes an interdigitated transducer 10, which includes a busbar unit (not labeled) and interdigitated electrode units (not labeled).

[0087] Specifically, the busbar unit includes at least two busbars 11, which are opposite each other in the first direction Y. The interdigital electrode unit is located between the two busbars 11. Referring to Figure 16, which shows a schematic diagram of the structure of the interdigital electrode unit provided in this embodiment, along the first direction Y, the region between the two busbars 11 is configured as a plurality of acoustic channels 101 based on the interdigital electrode unit. The portion of the interdigital electrode unit located in each acoustic channel 101 constitutes an interdigital electrode group 12. The structures of any two adjacent interdigital electrode groups 12 are different, and the resonant frequencies of the main modes in the plurality of acoustic channels 101 are the same.

[0088] In some embodiments, as shown in FIG16, at least one of the interdigital electrode groups includes a first interdigital electrode segment 1203 and a second interdigital electrode segment 1204 alternately arranged along the second direction, wherein the width A of the first interdigital electrode segment 1203 is... 21 The width A of the second interdigital electrode segment 1204 22 Unlike other interdigitated electrode segments, the spacing B2 between any two adjacent first interdigitated electrode segments 1203 and second interdigitated electrode segments 1204 is the same. For example, as shown in FIG16, the interdigitated electrode unit includes adjacent first interdigitated electrode groups and second interdigitated electrode groups. All interdigitated electrode segments 1200 in the first interdigitated electrode group 12c have the same width and are arranged at equal intervals (spacing B1). The second interdigitated electrode group 12d includes multiple first interdigitated electrode segments 1203 and multiple second interdigitated electrode segments 1204. The width A21 of the first interdigitated electrode segment 1203 is greater than the width A of the second interdigitated electrode segment. 22 The distance between any two adjacent first interdigital electrode segments 1203 and second interdigital electrode segments 1204 is B2.

[0089] In this second embodiment, for adjacent first interdigital electrode groups 12c and second interdigital electrode groups 12d, the electrode period length of the first interdigital electrode group 12c is C1 (C1 = A1 + B1), and the duty cycle of the first interdigital electrode group 12c is A1 / C1. The electrode period length of the second interdigital electrode group 12d is (C1 / C1). 21 +C 22 ) / 2, C21 =A 21 +B2, C 22 =A 22 +B2, the duty cycle of the second interdigital electrode group 12d is 2(A 21 +A 22 ) / (C 21 +C 22 ), where C 21 With C 22 These are the distances between any second interdigital electrode segment 1204 and its two adjacent first interdigital electrode segments 1203, respectively. The electrode period length C1 of the first interdigital electrode group 12c is greater than the electrode period length (C1) of the second interdigital electrode group 12d. 21 +C 22 ) / 2, and the duty cycle C1 of the first interdigital electrode group 12c is less than the duty cycle 2(A) of the second interdigital electrode group 12d. 21 +A 22 ) / (C 21 +C 22 This design enables consistency in the resonant frequencies of the dominant modes in the acoustic channels of the first interdigital electrode group 12c and the second interdigital electrode group 12d. It should be noted that although the widths of the interdigital electrode segments in the second interdigital electrode group 12d alternate, causing the electrode period length and duty cycle within the second interdigital electrode group 12d to alternate accordingly, the final superimposed electrode period length and duty cycle within the entire second interdigital electrode group 12d can meet the consistency requirements of its dominant mode resonant frequency with that of the adjacent interdigital electrode group (e.g., the first interdigital electrode group 12c). Furthermore, the alternating changes in the electrode period length and duty cycle of the interdigital electrode groups within the same acoustic channel can, to a certain extent, further disperse the excitation position and intensity of clutter.

[0090] The resonator in this second embodiment, based on the first embodiment, adjusts the structure of some interdigital electrode groups in the interdigital electrode unit, which can achieve flexible design of the resonator structure while improving the out-of-band suppression performance of the resonator.

[0091] Example 3

[0092] This third embodiment provides a resonator. The main difference between this third embodiment and embodiments one and two is that the resonators in embodiments one and two only include a segmented first interdigital electrode, while the resonator in this third embodiment also includes a non-segmented second interdigital electrode. Please refer to Figure 17, which shows a schematic diagram of one structure of the resonator. The resonator includes an interdigital transducer 10, which includes a busbar unit (not labeled) and an interdigital electrode unit (not labeled).

[0093] Specifically, the busbar unit includes at least two busbars 11, which are opposite each other in a first direction Y. The interdigital electrode unit is located between the two busbars 11. Along the first direction Y, the region between the two busbars 11 is configured as a plurality of acoustic channels 101 based on the interdigital electrode unit. The portion of the interdigital electrode unit located in each acoustic channel 101 constitutes an interdigital electrode group 12. Any two adjacent interdigital electrode groups 12 have different structures, and the resonant frequencies of the dominant modes in the plurality of acoustic channels 101 are the same.

[0094] In some embodiments, as shown in FIG17, the interdigital electrode unit further includes a plurality of second interdigital electrodes 121, which are alternately arranged with n first interdigital electrodes 120 (not shown), or the plurality of second interdigital electrodes 121 and n first interdigital electrodes 120 are alternately arranged at intervals (as shown in FIG17, two or more first interdigital electrodes 120 are spaced apart between two adjacent second interdigital electrodes 121). The width of the portion of the second interdigital electrode 121 located in any two adjacent interdigital electrode groups 12 is the same. That is, under the condition that the resonant frequency of the master mode in different acoustic channels is the same, it is not strictly required that each interdigital electrode in the interdigital electrode unit is a segmented structure, and a part of the conventional interdigital electrode structure (i.e., a rectangular continuous structure) can also be maintained to achieve flexible design of the resonator structure.

[0095] The resonator in this third embodiment, based on the first embodiment, adjusts the structure of some of the interdigitated electrodes in the interdigitated electrode unit, which can achieve flexible design of the resonator structure while improving the out-of-band suppression performance of the resonator.

[0096] Example 4

[0097] This fourth embodiment provides a method for manufacturing a resonator, which is used to manufacture the resonator as described in embodiments one to three or other suitable resonators. Referring to Figure 5, the resonator includes an interdigital transducer 10, and the manufacturing method includes the following steps:

[0098] An interdigital transducer 10 is formed. The interdigital transducer 10 includes a busbar unit and an interdigital electrode unit. The busbar unit includes at least two busbars 11. The two busbars 11 are opposite each other in a first direction. The interdigital electrode unit is located between the two busbars 11. Along the first direction Y, the region between the two busbars 11 is configured as a plurality of acoustic channels 101 based on the interdigital electrode unit. The portion of the interdigital electrode unit located in each acoustic channel 101 constitutes an interdigital electrode group 12. Any two adjacent interdigital electrode groups 12 have different structures, and the resonant frequencies of the dominant modes in the plurality of acoustic channels 101 are the same.

[0099] The resonator fabrication method in this embodiment four can produce a resonator structure with improved out-of-band suppression performance, and the fabrication steps are simple and easy to implement.

[0100] In summary, the resonator of this application, through the design of the interdigital electrode unit structure, divides the area between two busbars into multiple acoustic channels, with the portion of the interdigital electrode unit located in each acoustic channel forming an interdigital electrode group. By adjusting and controlling the structure of multiple interdigital electrode groups, even when the structures of any two adjacent interdigital electrode groups are different, the resonant frequencies of the master modes excited by the interdigital electrode groups in multiple acoustic channels are the same, ensuring that the resonant frequency, anti-resonant frequency, and Q value of the resonator remain stable regardless of changes in the structure of the interdigital electrode units. Simultaneously, because the structures of any two adjacent interdigital electrode groups are different, the frequency positions of clutter excitation in different acoustic channels are different, thereby dispersing the clutter excitation position and intensity, and improving the out-of-band suppression performance of the resonator. Furthermore, while satisfying the out-of-band suppression performance of the resonator, the structure of the interdigital electrodes and the structure of the interdigital electrode groups in the resonator can be flexibly adjusted according to actual needs. The resonator manufacturing method of this application can produce a resonator structure with improved out-of-band suppression performance, and the manufacturing steps are simple and easy to implement. Therefore, this application effectively overcomes the various shortcomings of the prior art and has high industrial applicability.

[0101] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0102] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A resonator, characterized in that, Includes an interdigital transducer, the interdigital transducer comprising: A busbar unit includes at least two busbars, the two busbars being opposite each other in a first direction; An interdigital electrode unit is located between two of the busbars; along the first direction, the region between the two busbars is configured into multiple acoustic channels based on the interdigital electrode unit, and the portion of the interdigital electrode unit located in each of the acoustic channels constitutes an interdigital electrode group; wherein... Any two adjacent interdigital electrode groups have different structures, and the main modes in the multiple acoustic channels have the same resonant frequency.

2. The resonator according to claim 1, characterized in that, The interdigitated electrode unit includes n first interdigitated electrodes, which are arranged along a second direction, n>1, and the second direction intersects the first direction. Each first interdigitated electrode includes multiple interdigitated electrode segments connected sequentially along the first direction. The segmentation surface between any two adjacent interdigitated electrode segments is parallel to the second direction. The multiple segmentation surfaces that are flush with each other in the first direction in the interdigitated electrode unit constitute an interface. The area between the two busbars is configured as multiple acoustic channels through the interface in the interdigitated electrode unit.

3. The resonator according to claim 2, characterized in that, The structural differences between any two adjacent interdigitated electrode groups include at least one of the following: different widths of the interdigitated electrode segments, different spacing between two adjacent interdigitated electrode segments, different duty cycles of the interdigitated electrode groups, different electrode period lengths of the interdigitated electrode groups, and different relative film thicknesses of the interdigitated electrode groups.

4. The resonator according to claim 2, characterized in that, The main modes in multiple acoustic channels have the same resonant frequency, which is achieved by coordinating the adjustment of the duty cycle of the interdigital electrode groups located in different acoustic channels and the electrode period length of the interdigital electrode groups.

5. The resonator according to claim 2, characterized in that, The interdigitated electrode unit includes an adjacent i-th interdigitated electrode group and an i+1-th interdigitated electrode group, wherein the duty cycle of the i+1-th interdigitated electrode group is greater than the duty cycle of the i-th interdigitated electrode group, and the electrode period length of the i+1-th interdigitated electrode group is less than the electrode period length of the i-th interdigitated electrode group.

6. The resonator according to claim 2, characterized in that, Each of the first interdigital electrodes includes an adjacent i-th interdigital electrode segment and an i+1-th interdigital electrode segment. Along the second direction, the distance between the central axis of the i-th interdigital electrode segment and the central axis of the i+1-th interdigital electrode segment in the n first interdigital electrodes first decreases and then increases.

7. The resonator according to claim 6, characterized in that, Both the i-th interdigitated electrode segment and the (i+1)-th interdigitated electrode segment include a first edge and a second edge opposite to each other in the second direction, where i≥1; The interdigitated electrode unit includes a first edge interdigitated electrode and a second edge interdigitated electrode, wherein, in the second direction, the first edge interdigitated electrode and the second edge interdigitated electrode are respectively located at both ends of the interdigitated electrode unit; wherein, In the first edge interdigitated electrode: the first edge of the i-th interdigitated electrode segment is aligned with the first edge of the (i+1)-th interdigitated electrode segment; In the second edge interdigitated electrode: the second edge of the i-th interdigitated electrode segment is aligned with the second edge of the (i+1)-th interdigitated electrode segment.

8. The resonator according to claim 7, characterized in that, In the second direction, all the interdigitated electrode segments within any interdigitated electrode group have the same width, and the spacing between any two adjacent interdigitated electrode segments within the same interdigitated electrode group is equal.

9. The resonator according to claim 8, characterized in that, The width of the i-th interdigitated electrode segment is different from the width of the (i+1)-th interdigitated electrode segment; in the interdigitated electrode unit, any first interdigitated electrode located between the first edge interdigitated electrode and the second edge interdigitated electrode satisfies the following: the distance between the first edge of the i-th interdigitated electrode segment and the first edge of the (i+1)-th interdigitated electrode segment increases as the distance between the first interdigitated electrode and the first edge interdigitated electrode increases; the distance between the second edge of the i-th interdigitated electrode segment and the second edge of the (i+1)-th interdigitated electrode segment increases as the distance between the first interdigitated electrode and the second edge interdigitated electrode increases.

10. The resonator according to claim 8, characterized in that, The interdigitated electrode unit further includes an m-th intermediate interdigitated electrode, which is located between the first edge interdigitated electrode and the second edge interdigitated electrode, where 1 < m < n. In the m-th intermediate interdigitated electrode, the offset distance between the i-th interdigitated electrode segment and the (i+1)-th interdigitated electrode segment is (m-1) × (A). i -A i+1 ) / (n-1), where A i A is the width of the i-th interdigital electrode segment of the m-th intermediate interdigital electrode. i+1 The width of the (i+1)th interdigital electrode segment of the m-th intermediate interdigital electrode.

11. The resonator according to claim 2, characterized in that: At least one of the interdigital electrode groups includes a first interdigital electrode segment and a second interdigital electrode segment arranged alternately along the second direction, wherein the width of the first interdigital electrode segment is different from the width of the second interdigital electrode segment, and the spacing between any adjacent first interdigital electrode segments and second interdigital electrode segments is the same.

12. The resonator according to claim 2, characterized in that: The interdigitated electrode unit further includes a plurality of second interdigitated electrodes, which are arranged alternately with n first interdigitated electrodes, or the plurality of second interdigitated electrodes are arranged alternately with n first interdigitated electrodes at intervals; the width of the portion of the second interdigitated electrode located in any two adjacent interdigitated electrode groups is the same.

13. The resonator according to any one of claims 2-12, characterized in that: The resonator further includes two reflective gratings, which are arranged on both sides of the interdigital transducer in the second direction. The gratings have at least one of a continuous rectangular structure and a segmented structure.

14. The resonator according to any one of claims 2-12, characterized in that: The interdigital transducer further includes a plurality of dummy fingers, which are located between any of the first interdigital electrodes and the busbars not connected to the first interdigital electrode, and there is a gap between the end of the dummy finger near the first interdigital electrode and the first interdigital electrode.

15. A method for manufacturing a resonator, characterized in that, The resonator includes an interdigital transducer, and the fabrication method includes the following steps: An interdigital transducer is formed, comprising a busbar unit and an interdigital electrode unit. The busbar unit includes at least two busbars facing each other in a first direction. The interdigital electrode unit is located between the two busbars. Along the first direction, the region between the two busbars is configured as multiple acoustic channels based on the interdigital electrode unit. The portion of the interdigital electrode unit located in each acoustic channel constitutes an interdigital electrode group. Any two adjacent interdigital electrode groups have different structures, and the main modes in the multiple acoustic channels have the same resonant frequency.

Images