Interdigital transducer structure, filter structure and electronic device

Abstract

Provided in the present application are an interdigital transducer structure, a filter structure and an electronic device. The interdigital transducer structure comprises a plurality of first electrode fingers and a plurality of second electrode fingers, which are spaced apart from each other between two busbars, wherein weighted connecting strips are located in unipolar regions; and, in a second direction, a preset distance is present between the projection of each load structure on an electrode finger and the edge of a free end of the electrode finger. In the present application, by means of providing the weighted connecting strips in the unipolar regions and providing the load structures in an interdigital region, a transverse mode within the passband of a radio frequency filter is suppressed, and the loss is reduced. Besides this, by means of the staggered arrangement of the weighted connecting strips, the transverse mode is further suppressed. Moreover, by means of cooperation with the provision of weighted connecting posts, weighted sub-portions and auxiliary weighted portions, the suppression effect on the transverse mode is further improved. Finally, by means of using weighted transverse strips or primary weighted portions as the load structures, the suppression effect on the transverse mode is further improved.

Description

An interdigital transducer structure, a filter structure and an electronic device Technical Field

[0001] The present application belongs to the field of semiconductor integrated circuit manufacturing technology, and in particular relates to an interdigital transducer structure, a filter structure and an electronic device. Background Art

[0002] As communication technology evolves from 2G to 5G, the number of communication frequency bands has gradually increased (from 4 frequency bands in 2G to more than 50 frequency bands in 5G). In order to improve the compatibility of smartphones with different communication standards, the amount of filters required for 5G smartphones will increase significantly, driving large-scale growth in the filter market. The RF filters currently widely used in wireless communication terminals are surface acoustic wave filters, which are responsible for filtering RF signals in the receiving and transmitting channels and outputting signals of specific frequencies from the various input RF signals. At the same time, with the continuous development of mobile communication technology and the development of RF front-end modularization, the popularization of high-end applications has led to the demand for filters becoming more complex, high-end, and miniaturized.

[0003] Conventional SAW (Surface Acoustic Wave) filters are currently widely used in RF filters. However, for high-end devices, the performance degradation caused by the transverse modes of conventional SAW structures makes it difficult to meet the requirements of RF front-end chips. Conventional SAW, as a conventional design, has a structure shown in Figure 1, consisting only of a conventional bus bar 61 and interdigitated electrode strips 62. Conventional SAW, used as a resonator and RF filter, produces strong transverse modes, making it difficult to meet the low insertion loss requirements of high-end device designs.

[0004] Therefore, there is an urgent need for a filter structure that can effectively suppress the transverse mode of SAW in radio frequency applications.

[0005] It should be noted that the above introduction to the technical background is only for the convenience of providing a clear and complete description of the technical solutions of this application and for the convenience of understanding by those skilled in the art. It cannot be considered that the above technical solutions are well known to those skilled in the art simply because these solutions are explained in the background technology part of this application.

[0006] Summary of the Invention

[0007] In view of the above shortcomings of the prior art, the purpose of this application is to provide an interdigital transducer structure, a filter structure and an electronic device to solve the problems of large insertion loss and poor performance of the transverse mode of the surface acoustic wave filter in the prior art in radio frequency applications.

[0008] In a first aspect, the present application provides an interdigital transducer structure, which includes: a bus bar, an electrode bar, a weighted connecting bar and a load structure; the bus bar includes a first bus bar and a second bus bar arranged in parallel, and the electrode bar includes a first electrode bar and a second electrode bar; a plurality of the first electrode bars are arranged on the first bus bar, and a plurality of the second electrode bars are arranged on the second bus bar, and the plurality of first electrode bars and the plurality of second electrode bars are relatively spaced and arranged in an intermediate area between the first bus bar and the second bus bar; the end of the electrode bar connected to the bus bar is a connecting end, and the end of the electrode bar away from the connecting end is a free end; the direction parallel to the first bus bar is a first direction, and the direction perpendicular to the first bus bar is a first direction. The direction in the first direction and parallel to the plane where the interdigital transducer structure is located is the second direction, and the third direction is perpendicular to both the first direction and the second direction; the intermediate area includes an interdigital area and a unipolar area that does not belong to the interdigital area, and the interdigital area is the area formed between the edge of the free end of the first electrode strip and the edge of the free end of the second electrode strip; the weighted connecting strip is located in the unipolar area, and the weighted connecting strip is located between the free end of the first electrode strip and the second bus bar, and / or between the free end of the second electrode strip and the first bus bar; there is a preset distance in the second direction between the projection of the load structure on the electrode strip and the edge of the free end of the electrode strip.

[0009] Optionally, the load structure is a primary weighting part, which is respectively located on the surface of the free end of the first electrode strip, and / or the surface of the second electrode strip at a position corresponding to the free end of the first electrode strip in the first direction, and / or the surface of the free end of the second electrode strip, and / or the surface of the first electrode strip at a position corresponding to the free end of the second electrode strip in the first direction.

[0010] Optionally, each of the primary weight portions includes at least two sub-weight portions arranged along the second direction.

[0011] Optionally, the weighted connecting bar includes a first weighted connecting bar and a second weighted connecting bar, and the second weighted connecting bar is connected to the second bus bar at a position corresponding to the first electrode bar along the second direction through a weighted connecting column, and the first weighted connecting bar is connected to the first bus bar at a position corresponding to the second electrode bar along the second direction through a weighted connecting column.

[0012] Optionally, a secondary weight portion is provided on each of the weighted connecting columns.

[0013] Optionally, the load structure is a weighted horizontal bar, which is parallel to the first direction, one of the weighted horizontal bars is arranged on the surface of the free end of the first electrode bar in the second direction, and the other weighted horizontal bar is arranged on the surface of the free end of the second electrode bar in the second direction.

[0014] Optionally, in the interdigitated area, an auxiliary weighting portion is provided on the first electrode strip and the second electrode strip near the two weighting horizontal strips; the auxiliary weighting portion is provided between the two weighting horizontal strips, or the auxiliary weighting portion is not provided between the two weighting horizontal strips.

[0015] Optionally, the weighted connecting strips include a first weighted connecting strip and a second weighted connecting strip, the projections of the first weighted connecting strip in the first direction overlap, and the projections of the second weighted connecting strip in the first direction overlap; the lengths of the first weighted connecting strip and the second weighted connecting strip parallel to the second direction are both 0.02λ-0.25λ, the minimum distance between each free end and the weighted connecting strip closest to it parallel to the second direction is 0.02λ-0.4λ, and the minimum distance between each free end and the bus bar closest to it parallel to the second direction is 1λ-2λ; when the load structure is a primary weighted part, the projection of each primary weighted part on the plane where the interdigital transducer structure is located is located inside the projection of the electrode strip where each primary weighted part is located on the plane where the interdigital transducer structure is located, the length of the electrode strip where the primary weighted part is located in the first direction is greater than the length of the primary weighted part in the first direction, and the length of each primary weighted part parallel to the second direction is 0.5λ-1λ; λ is the wavelength of the surface acoustic wave propagating in the interdigital transducer structure.

[0016] Optionally, the weighted connecting strips include a first weighted connecting strip and a second weighted connecting strip, and the two adjacent first weighted connecting strips along the first direction are staggered in the second direction so that the projections of the two adjacent first weighted connecting strips in the first direction do not overlap; the two adjacent second weighted connecting strips along the first direction are staggered in the second direction so that the projections of the two adjacent second weighted connecting strips in the first direction do not overlap.

[0017] Optionally, the minimum distances between two adjacent first weighted connecting strips along the first direction and their corresponding second electrode strips in the second direction are 0.02λ-0.4λ and 0.1λ-0.6λ respectively, and the minimum distances between two adjacent second weighted connecting strips along the first direction and their corresponding first electrode strips in the second direction are 0.02λ-0.4λ and 0.1λ-0.6λ respectively, and the lengths of the first weighted connecting strip and the second weighted connecting strip parallel to the second direction are both 0.02λ-0.25λ; λ is the wavelength of the surface acoustic wave propagating in the interdigital transducer structure.

[0018] In a second aspect, the present application further provides a filter structure, which includes any one of the above-mentioned interdigital transducer structures.

[0019] Optionally, the filter structure further includes two reflection grating arrays, which are respectively arranged on both sides of the interdigital transducer structure along the first direction, each of the reflection grating arrays is composed of at least two metal reflection strips and two auxiliary bus bars, the metal reflection strips are parallel to the second direction and arranged along the first direction, and each of the metal reflection strips is respectively in contact with the two auxiliary bus bars at both ends in the second direction, and a reflection grating load structure is provided on the reflection grating array at a position where the projection of the load structure of the interdigital transducer structure in the first direction coincides with that of the load structure.

[0020] Optionally, when the load structure of the interdigital transduction structure is a primary weighting part, the reflective grating load structure is also a primary weighting part, and the primary weighting part of the reflective grating array is located at a position on the metal reflective strip corresponding to the primary weighting part of the interdigital transduction structure in the first direction.

[0021] Optionally, when the primary weighting portion of the interdigital transduction structure is at least two sub-weighting portions, each primary weighting portion on the metal reflective strip is also at least two sub-weighting portions arranged along the second direction, and the sub-weighting portions of the reflective grating array are located at positions on the metal reflective strip corresponding to the sub-weighting portions of the interdigital transduction structure in the first direction.

[0022] Optionally, when the load structure of the IDT structure is a weighted horizontal bar, the reflective grating load structure is also a weighted horizontal bar, and the weighted horizontal bars of the reflective grating array are connected to the weighted horizontal bars of the IDT structure and their projections in the first direction overlap.

[0023] Optionally, when the interdigital transduction structure is provided with an auxiliary weighting portion, the reflective grating array is also provided with an auxiliary weighting portion, and the auxiliary weighting portion of the reflective grating array is located at a position on the metal reflective strip corresponding to the auxiliary weighting portion of the interdigital transduction structure in the first direction.

[0024] In a third aspect, the present application further provides an electronic device, which includes any one of the filter structures described above.

[0025] As described above, the interdigital transducer structure, filter structure, and electronic device of the present application have the following beneficial effects:

[0026] This application suppresses the transverse mode within the RF filter band and reduces losses by arranging a weighted connecting strip in the monopole region and a load structure in the interdigital region;

[0027] Furthermore, a load structure arranged in the interdigital area has a preset distance in the second direction between its projection on the electrode strip and the edge of the free end of the electrode strip, which can make the lateral mode suppression effect within the RF filter band better and the flatness within the passband better, further improve the characteristics of the RF filter, and enhance the performance of the RF filter.

[0028] This application further suppresses the lateral mode by staggering the weighted connecting strips;

[0029] This application cooperates with the arrangement of weighted connecting columns, sub-weighted parts and auxiliary weighted parts to further improve the suppression effect of the lateral mode;

[0030] The present application further improves the suppression effect of the transverse mode by using the load structure as a weighted horizontal bar or a primary weighted part. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the implementation methods of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the implementation methods or the description of the prior art. Obviously, the drawings described below are only some implementation methods recorded in this application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0032] FIG1 is a schematic diagram showing the structure of a common SAW in the prior art.

[0033] FIG2 is a schematic structural diagram of an interdigital transducer structure provided with a primary weighting portion in Example 1 of the present application.

[0034] FIG3 is a comparison diagram showing the resonance curves of the filters obtained by the interdigital transducer structure in the prior art and in Example 1. FIG.

[0035] FIG. 4 is a comparison diagram showing the resonance curves of filters obtained by the interdigital transducer structure in the prior art and in Example 1. FIG.

[0036] FIG5 is a comparison diagram showing the resonance curves of the filters obtained by the interdigital transducer structure in the prior art and in Example 1. FIG.

[0037] FIG6 is a comparison diagram showing the resonance curves of the filters obtained by the interdigital transducer structure in the prior art and in Example 1. FIG.

[0038] FIG. 7 is a comparison diagram showing the resonance curves of the filters obtained by the interdigital transducer structure in the prior art and in Example 1. FIG.

[0039] FIG8 is an enlarged schematic diagram showing the structure of the interdigital transducer structure provided with a primary weighting portion in Example 1 of the present application.

[0040] FIG9 is a schematic structural diagram of an interdigital transducer structure with staggered weighted connecting strips in an optional example of Embodiment 1 of the present application.

[0041] FIG10 is an enlarged schematic diagram showing the structure of an interdigital transducer structure with staggered weighted connecting strips in an optional example of Embodiment 1 of the present application.

[0042] FIG11 is a schematic structural diagram of an IDT structure provided with a sub-weighting portion in Example 2 of the present application.

[0043] FIG12 is an enlarged schematic diagram showing the structure of the interdigital transducer structure provided with a sub-weighting portion in Example 2 of the present application.

[0044] FIG13 is a schematic structural diagram of an interdigital transducer structure with staggered weighted connecting strips in an optional example of Embodiment 2 of the present application.

[0045] FIG14 is an enlarged schematic diagram showing the structure of an interdigital transducer structure with staggered weighted connecting strips in an optional example of Embodiment 2 of the present application.

[0046] FIG15 is a schematic structural diagram of an interdigital transducer structure with weighted connecting posts in Example 3 of the present application.

[0047] FIG16 is an enlarged schematic diagram showing the structure of the interdigital transducer structure with weighted connecting posts in Example 3 of the present application.

[0048] FIG17 is a schematic structural diagram of an interdigital transducer structure provided with a secondary weighting portion in Example 4 of the present application.

[0049] FIG18 is an enlarged schematic diagram showing the structure of the interdigital transducer structure provided with a secondary weighting portion in Example 4 of the present application.

[0050] FIG19 is a schematic structural diagram of an IDT structure with weighted horizontal bars in Example 5 of the present application.

[0051] FIG20 is an enlarged schematic diagram showing the structure of the interdigital transducer structure with weighted horizontal bars in Example 5 of the present application.

[0052] FIG21 is a schematic structural diagram of an interdigital transducer structure with staggered weighted connecting strips in an optional example of Example 5 of the present application.

[0053] FIG22 is an enlarged schematic diagram showing the structure of an interdigital transducer structure with staggered weighted connecting strips in an optional example of Example 5 of the present application.

[0054] FIG23 is a schematic structural diagram of an interdigital transducer structure provided with an auxiliary weighting portion in Example 6 of the present application.

[0055] FIG24 is an enlarged schematic diagram showing the structure of the interdigital transducer structure provided with an auxiliary weighting portion in Example 6 of the present application.

[0056] FIG25 is a schematic structural diagram of an interdigital transducer structure with staggered weighted connecting strips in an optional example of Example 6 of the present application.

[0057] FIG26 is an enlarged schematic diagram showing the structure of an interdigital transducer structure with staggered weighted connecting strips in an optional example of Example 6 of the present application.

[0058] FIG27 shows a schematic structural diagram of a filter structure in an optional example of Example 7 of the present application. DETAILED DESCRIPTION

[0059] The following describes the embodiments of the present application through specific examples. Those skilled in the art will readily understand the other advantages and benefits of the present application from the disclosure herein. The present application may also be implemented or applied through various other specific embodiments, and the details in this specification may be modified or altered based on different viewpoints and applications without departing from the spirit of the present application.

[0060] For example, when describing the embodiments of this application, schematic diagrams showing device structures may be partially enlarged for ease of explanation. These schematic diagrams are merely illustrative and should not limit the scope of protection of this application. Furthermore, in actual production, the three-dimensional dimensions of length, width, and depth should be included.

[0061] For convenience of description, spatially relative terms such as "under," "below," "below," "below," "above," and "upper" may be used herein to describe the relationship of one element or feature to other elements or features shown in the drawings. It will be understood that these spatially relative terms are intended to encompass other orientations of the device in use or operation in addition to the orientation depicted in the drawings.

[0062] In the context of the present application, a structure described as a first feature being "above" a second feature may include embodiments where the first and second features are in direct contact, and may also include embodiments where additional features are formed between the first and second features, such that the first and second features may not be in direct contact.

[0063] It should be noted that the illustrations provided in the various embodiments of the present application are only used to schematically illustrate the basic concept of the present application. Therefore, the illustrations only show the components related to the present application rather than being drawn according to the number, shape and size of the components in actual implementation. In actual implementation, the type, quantity and proportion of each component may be changed at will, and the component layout may also be more complicated.

[0064] The "first direction" involved in this application is the x-direction shown in the figure, the "second direction" is the y-direction shown in the figure, and the "third direction" is the direction perpendicular to the paper surface and is not shown in the figure. The directions defined here are only for convenience of illustration. The actual reference system of the directions can be set according to the application and are all within the scope of protection of this application.

[0065] Numerical ranges in the context of this application include the limits of the range.

[0066] Example 1:

[0067] As shown in FIG2 , this embodiment provides an IDT structure, which includes: bus bars, electrode bars, weighted connecting bars, and a load structure;

[0068] The busbar includes a first busbar 11 and a second busbar 12 arranged in parallel, and the electrode strips include a first electrode strip 21 and a second electrode strip 22; a plurality of the first electrode strips 21 are provided on the first busbar 11, and a plurality of the second electrode strips 22 are provided on the second busbar 12, and the plurality of first electrode strips 21 and the plurality of second electrode strips 22 are relatively spaced and arranged in an intermediate area between the first busbar 11 and the second busbar 12; the end of the electrode strip connected to the busbar is a connecting end 23, and the end of the electrode strip away from the connecting end 23 is a free end 24; a direction parallel to the first busbar 11 is a first direction, a direction perpendicular to the first direction and parallel to the plane where the interdigital transducer structure is located is a second direction, and a third direction is perpendicular to both the first direction and the second direction;

[0069] The middle region includes an interdigital region B and a unipolar region A that does not belong to the interdigital region B. The interdigital region B is a region formed between an edge of the free end 24 of the first electrode strip 21 and an edge of the free end 24 of the second electrode strip 22.

[0070] The weighted connecting bar is located in the monopolar region A, and the weighted connecting bar is located between the free end 24 of the first electrode bar 21 and the second bus bar 12, and / or between the free end 24 of the second electrode bar 12 and the first bus bar 11;

[0071] There is a preset distance in the second direction between the projection of the load structure on the electrode strip and the edge of the free end 24 of the electrode strip.

[0072] The present application sets the load structure on the two end surfaces of the interdigital region B along the second direction, and adjusts the sound velocity of the monopole region A and the interdigital region B through the load structure to achieve maximum suppression of transverse mode ripples; in addition, by setting a preset distance between the projection of the load structure on the electrode strip and the edge of the free end 24 in the second direction, the cost required for the load structure is reduced, and at the same time, the risk of short circuit between the electrode strips due to the existence of the load structure is avoided.

[0073] In addition, after testing, in the comparative test, a comparison is made based on whether there is a preset distance in the second direction between the projection of the load structure on the electrode strip and the edge of the free end 24. The presence of a preset distance in the second direction between the projection of the load structure on the electrode strip and the edge of the free end 24 is better than the absence of a preset distance in the second direction between the projection of the load structure on the electrode strip and the edge of the free end 24 (that is, the projection of the load structure on the electrode strip coincides with the edge of the free end 24, for example, the load structure is set on the edge of the free end, and the distance from the edge is zero). This can make the lateral mode suppression effect within the RF filter band better, the flatness within the passband better, further improve the characteristics of the RF filter, and enhance the performance of the RF filter. Specifically, FIG2 shows the case where the weighted connecting strip is set between the free end 24 of the first electrode strip 21 and the second bus bar 12, and between the free end 24 of the second electrode strip 22 and the first bus bar 11. The weighted connecting strip can also be set at only one of them.

[0074] In one embodiment, the load structure may be on the upper surface and / or lower surface of the electrode strip. FIG2 is a schematic diagram of the structure of the load structure on the upper surface of the electrode strip.

[0075] In one embodiment, an additional layer is provided between the load structure and the electrode strips.

[0076] In one embodiment, the additional layer is a temperature compensation layer and / or a passivation layer.

[0077] In one embodiment, the load structure is a primary weighting portion 51, and the primary weighting portion 51 is respectively located on the surface of the free end 24 of the first electrode strip 21, and / or the surface of the second electrode strip 22 at a position corresponding to the free end 24 of the first electrode strip 21 in the first direction, and / or the surface of the free end 24 of the second electrode strip 22, and / or the surface of the first electrode strip 21 at a position corresponding to the free end 24 of the second electrode strip 22 in the first direction.

[0078] Specifically, as shown in Figure 2, the primary weighting portion 51 is set in all four of the above-mentioned positions. The primary weighting portion 51 can also be set in any one of the above-mentioned four positions or any combination of more than one. It can be adjusted and selected according to the cost and performance requirements of the SAW, and all fall within the scope of protection of this application.

[0079] Specifically, the surface on which the primary weighting part 51 is located includes an upper surface and / or a lower surface, or a structure with an additional layer arranged between the surface. The additional layer may be a temperature compensation layer and / or a passivation layer, etc., all of which fall within the scope of protection of this application. Figure 2 is a schematic diagram of the structure of the primary weighting part 51 on the upper surface of the electrode strip.

[0080] The present application further improves the acoustic wave propagation properties between the monopole region A and the interdigital region B by providing a primary weighting portion 51 on the surface of the free end 24 within the interdigital region B and the corresponding electrode strip surface, thereby further suppressing the transverse mode of the surface acoustic wave filter, reducing losses, and improving the quality factor. As shown in Figures 3-5, the resonance curves of a conventional SAW in the prior art and the present application with a weighted connecting strip and a primary weighting portion 51 are compared, where the prior art is represented by a dotted line and the present application's solution is represented by a solid line. It can be seen that compared with the prior art, the present application's solution significantly reduces the burrs and splitting phenomena in the resonance curve. Experiments have shown that a single weighted connecting strip and the primary weighting portion 51 have a better suppression effect on transverse mode ripples than multiple weighted connecting strips. As shown in Figures 6 and 7, the resonance curves are compared for a normal SAW (the dotted line curve in the figure), a SAW with only a primary weighting portion 51 (the dotted line curve in the figure), and a filter with a primary weighting portion 51 and a single weighting connecting strip (the solid line curve in the figure). It can be seen that the resonance curve of the filter with the primary weighting portion 51 and a single weighting connecting strip is the smoothest, the burr phenomenon is the smallest, the loss on both sides of the passband is smaller, and the quality factor obtained is the highest.

[0081] In one embodiment, FIG8 is an enlarged view of the load structure as a primary weighted portion 51 interdigital transducer structure, wherein the weighted connecting strips include a first weighted connecting strip 31 and a second weighted connecting strip 32 , wherein the projections of the first weighted connecting strip 31 in the first direction overlap, and the projections of the second weighted connecting strip 32 in the first direction overlap;

[0082] The lengths CB of the first weighted connecting bar 31 and the second weighted connecting bar 32 in parallel with the second direction are both 0.02λ-0.25λ, the minimum distance Gap2 between each free end 24 and the weighted connecting bar closest to it in parallel with the second direction is 0.02λ-0.4λ, and the minimum distance Gap1 between each free end 24 and the bus bar closest to it in parallel with the second direction is 1λ-2λ;

[0083] The projection of each primary weighted portion 51 on the plane where the interdigital transducer structure is located is located inside the projection of the electrode strip where each primary weighted portion 51 is located on the plane where the interdigital transducer structure is located, the length of the electrode strip where the primary weighted portion 51 is located in the first direction is greater than the length of the primary weighted portion 51 in the first direction, and the length Piston of each primary weighted portion 51 parallel to the second direction is 0.5λ-1λ;

[0084] The projection of each of the primary weighted portions 51 on the plane where the interdigital transducer structure is located is located inside the projection of the electrode strip where each of the primary weighted portions 51 is located on the plane where the interdigital transducer structure is located; the length of the electrode strip where each of the primary weighted portions 51 is located in the first direction is greater than the length of the primary weighted portion 51 in the first direction; the minimum distance Gap3 between each of the primary weighted portions 51 and the edge of the electrode strip where each of the primary weighted portions 51 is located, which is parallel to the first direction, is 0.005λ-0.03λ; and the minimum distance Gap4 between each of the primary weighted portions 51 and the edge of the electrode strip where each of the primary weighted portions 51 is located, which is parallel to the second direction, is 0.005λ-0.03λ;

[0085] λ is the wavelength of the surface acoustic wave propagating in the interdigital transducer structure.

[0086] This application further optimizes the sound wave propagation mode and reduces the transverse mode ripple by setting the width of the primary weighting part 51 to be smaller than the electrode strip. While optimizing the SAW performance, the number of primary weighting parts 51 required is reduced, the weight required for the filter is reduced, and the application of SAW miniaturization and lightness is facilitated.

[0087] In one embodiment, the primary weight portion 51 is a laminated structure of chromium, copper, and chromium from top to bottom along the third direction; or the primary weight portion 51 is a laminated structure of chromium, silver, and chromium from top to bottom along the third direction.

[0088] The present application further optimizes the suppression of the lateral mode by the primary weight part 51 by setting the material of the primary weight part 51 to a laminated structure of chromium / copper / chromium or chromium / silver / chromium. Experiments on various materials have shown that the laminated structures of chromium / copper / chromium and chromium / silver / chromium as the material of the primary weight part 51 can achieve optimal performance, while improving the adhesion of the primary weight part 51 to the electrode strip.

[0089] In one embodiment, as shown in Figure 9, the weighted connecting strips include a first weighted connecting strip 31 and a second weighted connecting strip 32. The two adjacent first weighted connecting strips 31 along the first direction are staggered in the second direction so that the projections of the two adjacent first weighted connecting strips 31 in the first direction do not overlap; the two adjacent second weighted connecting strips 32 along the first direction are staggered in the second direction so that the projections of the two adjacent second weighted connecting strips 32 in the first direction do not overlap.

[0090] The present application further improves the influence of the weighted connecting strips on the acoustic wave propagation properties between the monopole region A and the interdigitated region B by coordinating the structure of the weighted connecting strips with staggered distribution, thereby further optimizing the suppression effect on the transverse mode.

[0091] In one embodiment, FIG10 is an enlarged view of the interdigital transduction structure in which the weighted connecting strips 31 are staggered, wherein the minimum distances Gap5 and Gap6 between two adjacent first weighted connecting strips 31 and their corresponding second electrode strips 22 in the second direction are 0.02λ-0.4λ and 0.1λ-0.6λ, respectively; the minimum distances Gap5 and Gap6 between two adjacent second weighted connecting strips 32 and their corresponding first electrode strips 21 in the second direction are 0.02λ-0.4λ and 0.1λ-0.6λ, respectively; the lengths CB1 and CB2 of the first weighted connecting strip 31 and the second weighted connecting strip 32 parallel to the second direction are both 0.02λ-0.25λ; the minimum distance Gap1 between each free end 24 and the bus bar closest to it in the second direction is 1λ-2λ;

[0092] The projection of each primary weighted portion 51 on the plane where the interdigital transducer structure is located is located inside the projection of the electrode strip where each primary weighted portion 51 is located on the plane where the interdigital transducer structure is located, the length of the electrode strip where the primary weighted portion 51 is located in the first direction is greater than the length of the primary weighted portion 51 in the first direction, and the length Piston of each primary weighted portion 51 parallel to the second direction is 0.5λ-1λ;

[0093] The projection of each primary weighting portion 51 on the plane where the interdigital transducer structure is located is located inside the projection of the electrode strip where each primary weighting portion 51 is located on the plane where the interdigital transducer structure is located, the length of the electrode strip where the primary weighting portion 51 is located in the first direction is greater than the length of the primary weighting portion 51 in the first direction, the minimum distance Gap3 between each primary weighting portion 51 and the edge of the electrode strip where each primary weighting portion 51 is located parallel to the first direction is 0.005λ-0.03λ, and the minimum distance Gap4 between each primary weighting portion 51 and the edge of the electrode strip where each primary weighting portion 51 is located parallel to the second direction is 0.005λ-0.03λ; λ is the wavelength of the surface acoustic wave propagating in the interdigital transducer structure.

[0094] In one embodiment, the projections of two spaced-apart first weighted connecting strips 31 in the first direction overlap, and / or the projections of two spaced-apart second weighted connecting strips 32 in the first direction overlap.

[0095] In one embodiment, projections of two spaced-apart first weighted connecting strips 31 in the first direction do not overlap, and / or projections of two spaced-apart second weighted connecting strips 32 in the first direction do not overlap.

[0096] This embodiment can also be combined with any one or more combinations of any features in other embodiments to obtain a new structure, and the resulting structures are all within the scope of protection of this application.

[0097] Example 2:

[0098] This embodiment provides an IDT structure, which has the same features as the IDT structure in Embodiment 1, except that:

[0099] Each of the primary weight portions 51 includes at least two sub-weight portions 52 arranged along the second direction.

[0100] The present application further improves the primary emphasis portion 51 by dividing it into two sub-emphasis portions 52 , thereby further improving the acoustic wave propagation properties between the monopole region A and the interdigital region B and optimizing the suppression effect on the transverse mode.

[0101] In one embodiment, as shown in FIG11 , each of the primary weight portions 51 includes two sub-weight portions 52 arranged along the second direction.

[0102] In one embodiment, the plurality of sub-weighting portions 52 may be arranged in different arrays, and the specific arrangement may be adjusted according to actual structural requirements and experimental results.

[0103] In one embodiment, the weighted connecting strips include a first weighted connecting strip 31 and a second weighted connecting strip 32, wherein the projections of the first weighted connecting strip 31 in the first direction overlap, and the projections of the second weighted connecting strip 32 in the first direction overlap;

[0104] FIG12 is an enlarged view of the interdigital transducer structure including at least two sub-weighted portions 52 , wherein the lengths CB of the first weighted connecting strip 31 and the second weighted connecting strip 32 in parallel to the second direction are both 0.02λ-0.25λ, the minimum distance Gap2 between each free end 24 and the weighted connecting strip closest thereto in parallel to the second direction is 0.02λ-0.4λ, and the minimum distance Gap1 between each free end 24 and the bus bar closest thereto in parallel to the second direction is 1λ-2λ.

[0105] The projections of the two sub-weighting portions 52 on the plane where the interdigital transducer structure is located are located inside the projections of the electrode strips where the two sub-weighting portions 52 are located on the plane where the interdigital transducer structure is located, and the length of the electrode strips where the two sub-weighting portions 52 are located in the first direction is greater than the total length of the two sub-weighting portions 52 in the first direction;

[0106] The lengths Piston1 and Piston2 of the two sub-weight portions 52 in the second direction are both 0.2λ-1λ, and the minimum distance Gap7 between the two sub-weight portions 52 in the second direction is 0.1λ-1λ; the minimum distance Gap3 between each sub-weight portion 52 and an edge of the electrode strip where each sub-weight portion 52 is located, which is parallel to the first direction, is 0.005λ-0.03λ, and the minimum distance Gap4 between each sub-weight portion 52 and an edge of the electrode strip where each sub-weight portion 52 is located, which is parallel to the second direction, is 0.005λ-0.03λ;

[0107] λ is the wavelength of the surface acoustic wave propagating in the interdigital transducer structure.

[0108] In one embodiment, as shown in Figure 13, the weighted connecting strips include a first weighted connecting strip 31 and a second weighted connecting strip 32. The two adjacent first weighted connecting strips 31 along the first direction are staggered in the second direction so that the projections of the two adjacent first weighted connecting strips 31 in the first direction do not overlap; the two adjacent second weighted connecting strips 32 along the first direction are staggered in the second direction so that the projections of the two adjacent second weighted connecting strips 32 in the first direction do not overlap.

[0109] The present application further improves the influence of the weighted connecting strips on the acoustic wave propagation properties between the monopole region A and the interdigitated region B by coordinating the structure of the weighted connecting strips with staggered distribution, thereby further optimizing the suppression effect on the transverse mode.

[0110] In one embodiment, FIG14 is an enlarged view of the interdigital transduction structure in which the weighted connecting bars 31 are staggered, wherein the minimum distances Gap5 and Gap6 between two adjacent first weighted connecting bars 31 and their corresponding second electrode bars 22 in the second direction are 0.02λ-0.4λ and 0.1λ-0.6λ, respectively; the minimum distances Gap5 and Gap6 between two adjacent second weighted connecting bars 32 and their corresponding first electrode bars 21 in the second direction are 0.02λ-0.4λ and 0.1λ-0.6λ, respectively; the lengths CB1 and CB2 of the first weighted connecting bars 31 and the second weighted connecting bars 32 parallel to the second direction are both 0.02λ-0.25λ; the minimum distance Gap1 between each free end 24 and the bus bar closest to it in the second direction is 1λ-2λ;

[0111] The projections of the two sub-weighting portions 52 on the plane where the interdigital transducer structure is located are located inside the projections of the electrode strips where the two sub-weighting portions 52 are located on the plane where the interdigital transducer structure is located, and the length of the electrode strips where the two sub-weighting portions 52 are located in the first direction is greater than the total length of the two sub-weighting portions 52 in the first direction;

[0112] The lengths Piston1 and Piston2 of the two sub-weight portions 52 in the second direction are both 0.2λ-1λ, and the minimum distance Gap7 between the two sub-weight portions 52 in the second direction is 0.1λ-1λ; the minimum distance Gap3 between each sub-weight portion 52 and an edge of the electrode strip where each sub-weight portion 52 is located, which is parallel to the first direction, is 0.005λ-0.03λ, and the minimum distance Gap4 between each sub-weight portion 52 and an edge of the electrode strip where each sub-weight portion 52 is located, which is parallel to the second direction, is 0.005λ-0.03λ;

[0113] λ is the wavelength of the surface acoustic wave propagating in the interdigital transducer structure.

[0114] In one embodiment, the projections of two spaced-apart first weighted connecting strips 31 in the first direction overlap, and / or the projections of two spaced-apart second weighted connecting strips 32 in the first direction overlap.

[0115] In one embodiment, projections of two spaced-apart first weighted connecting strips 31 in the first direction do not overlap, and / or projections of two spaced-apart second weighted connecting strips 32 in the first direction do not overlap.

[0116] This embodiment can also be combined with any one or more combinations of any features in other embodiments to obtain a new structure, and the resulting structures are all within the scope of protection of this application.

[0117] Example 3:

[0118] This embodiment provides an IDT structure. The IDT structure has the same features as the IDT structure in Embodiment 1 or 2, except that:

[0119] The weighted connecting bar includes a first weighted connecting bar 31 and a second weighted connecting bar 32. The second weighted connecting bar 32 is connected to the second bus bar 12 at a position corresponding to the first electrode bar 21 along the second direction through a weighted connecting column 53. The first weighted connecting bar 31 is connected to the first bus bar 11 at a position corresponding to the second electrode bar 22 along the second direction through a weighted connecting column 53.

[0120] The present application further improves the acoustic wave propagation properties between the monopole region A and the interdigital region B and optimizes the suppression effect on the transverse mode by providing a weighted connecting column 53 between the adjacent weighted connecting bars and the bus bar for connection.

[0121] In one embodiment, as shown in FIG15 , the weighted connecting strips include a first weighted connecting strip 31 and a second weighted connecting strip 32 , wherein the projections of the first weighted connecting strip 31 in the first direction overlap, and the projections of the second weighted connecting strip 32 in the first direction overlap.

[0122] In one embodiment, as shown in FIG16 , which is an enlarged view of the above-mentioned interdigital transducer structure with weighted connecting posts 53, the minimum distance Gap3 between each primary weighted portion 51 and the edge of the electrode strip where each primary weighted portion 51 is located parallel to the first direction is 0.005λ-0.03λ, and the minimum distance Gap4 between each primary weighted portion 51 and the edge of the electrode strip where each primary weighted portion 51 is located parallel to the second direction is 0.005λ-0.03λ; the length Pitch1 of the weighted connecting post 53 corresponding to the first electrode strip 21 in the first direction is the same as that of the first electrode strip 21, and the length Pitch1 of the weighted connecting post 53 corresponding to the second electrode strip 22 in the first direction is the same as that of the second electrode strip 22, and λ is the wavelength of the surface acoustic wave propagating in the interdigital transducer structure;

[0123] The lengths CB of the first weighted connecting bar 31 and the second weighted connecting bar 32 in parallel with the second direction are both 0.02λ-0.25λ, the minimum distance Gap2 between each free end 24 and the weighted connecting bar closest to it in parallel with the second direction is 0.02λ-0.4λ, and the minimum distance Gap1 between each free end 24 and the bus bar closest to it in parallel with the second direction is 1λ-2λ;

[0124] When the load structure is a primary weighting portion 51, a projection of each primary weighting portion 51 on the plane where the interdigital transducer structure is located is located inside a projection of an electrode strip where each primary weighting portion 51 is located on the plane where the interdigital transducer structure is located, a length of the electrode strip where the primary weighting portion 51 is located in the first direction is greater than a length of the primary weighting portion 51 in the first direction, and a length Piston of each primary weighting portion 51 parallel to the second direction is 0.5λ-1λ;

[0125] λ is the wavelength of the surface acoustic wave propagating in the interdigital transducer structure.

[0126] In one embodiment, the projections of two spaced-apart first weighted connecting strips 31 in the first direction overlap, and / or the projections of two spaced-apart second weighted connecting strips 32 in the first direction overlap.

[0127] In one embodiment, projections of two spaced-apart first weighted connecting strips 31 in the first direction do not overlap, and / or projections of two spaced-apart second weighted connecting strips 32 in the first direction do not overlap.

[0128] This embodiment can also be combined with any one or more combinations of any features in other embodiments to obtain a new structure, and the resulting structures are all within the scope of protection of this application.

[0129] Example 4:

[0130] This embodiment provides an IDT structure, which has the same features as the IDT structure in Embodiment 3, except that:

[0131] A secondary weight portion 54 is provided on each of the weight connection columns 53 .

[0132] The present application further improves the acoustic wave propagation properties between the monopole region A and the interdigital region B by providing a secondary weighted portion 54 on the weighted connecting column 53 , thereby optimizing the suppression effect on the transverse mode.

[0133] In one embodiment, as shown in FIG17 , the weighted connecting strips include a first weighted connecting strip 31 and a second weighted connecting strip 32 , wherein the projections of the first weighted connecting strip 31 in the first direction overlap, and the projections of the second weighted connecting strip 32 in the first direction overlap.

[0134] In one embodiment, FIG18 is an enlarged view of the interdigital transducer structure provided with the secondary weighted portion 54, wherein the length Piston3 of the secondary weighted portion 54 in the second direction is 0.2λ-1λ; the minimum distance Gap10 between each secondary weighted portion 54 and the bus bar to which each secondary weighted portion 54 is close in the first direction is 0.005λ-0.03λ, and the minimum distance Gap11 between each secondary weighted portion 54 and the edge of the electrode strip where each secondary weighted portion 54 is located parallel to the second direction is 0.005λ-0.03λ. .03λ, the minimum distance Gap12 between each secondary weight portion 54 and the weight connection strip close to each secondary weight portion 54 in the first direction is 0.005λ-0.03λ; the minimum distance Gap3 between each primary weight portion 51 and the edge of the electrode strip where each primary weight portion 51 is located, which is parallel to the first direction, is 0.005λ-0.03λ, and the minimum distance Gap4 between each primary weight portion 51 and the edge of the electrode strip where each primary weight portion 51 is located, which is parallel to the second direction, is 0.005λ-0.03λ;

[0135] The lengths CB of the first weighted connecting bar 31 and the second weighted connecting bar 32 in parallel with the second direction are both 0.02λ-0.25λ, the minimum distance Gap2 between each free end 24 and the weighted connecting bar closest to it in parallel with the second direction is 0.02λ-0.4λ, and the minimum distance Gap1 between each free end 24 and the bus bar closest to it in parallel with the second direction is 1λ-2λ;

[0136] When the load structure is a primary weighting portion 51, a projection of each primary weighting portion 51 on the plane where the interdigital transducer structure is located is located inside a projection of an electrode strip where each primary weighting portion 51 is located on the plane where the interdigital transducer structure is located, a length of the electrode strip where the primary weighting portion 51 is located in the first direction is greater than a length of the primary weighting portion 51 in the first direction, and a length Piston of each primary weighting portion 51 parallel to the second direction is 0.5λ-1λ;

[0137] λ is the wavelength of the surface acoustic wave propagating in the interdigital transducer structure.

[0138] This embodiment can also be combined with any one or more combinations of any features in other embodiments to obtain a new structure, and the resulting structures are all within the scope of protection of this application.

[0139] Example 5:

[0140] This embodiment provides an IDT structure, which has the same features as the IDT structure in Embodiment 1, Embodiment 3, or Embodiment 4, except that:

[0141] The load structure is a weighted horizontal bar 55, which is parallel to the first direction. One weighted horizontal bar 55 is arranged on the surface of the free end 24 of the first electrode strip 21 in the second direction, and the other weighted horizontal bar 55 is arranged on the surface of the free end 24 of the second electrode strip 22 in the second direction.

[0142] Specifically, the surface on which the weighted horizontal bar 55 is located includes an upper surface and / or a lower surface, or a structure with an additional layer arranged between the surface. The additional layer may be a temperature compensation layer and / or a passivation layer, etc., all of which fall within the scope of protection of this application. As shown in Figures 19-22, these are schematic diagrams of the structure of the weighted horizontal bar 55 on the upper surface of the electrode strip.

[0143] The present application improves the acoustic wave propagation properties between the monopole region A and the interdigital region B by providing a weighted horizontal strip 55 in the interdigital region B, thereby optimizing the suppression effect on the transverse mode.

[0144] In one embodiment, a distance Gap8 between the weighted horizontal strip 55 and the edge of the free end 24 adjacent thereto in the second direction is 0.005λ-0.03λ, and a length S of the weighted horizontal strip 55 in the second direction is 0.5λ-1λ.

[0145] In one embodiment, the weighted horizontal strip 55 is made of silicon dioxide.

[0146] In one embodiment, as shown in FIG. 19 , the projections of the first weighted connecting strips 31 in the second direction overlap, and the projections of the second weighted connecting strips 32 in the second direction overlap.

[0147] In one embodiment, FIG20 is an enlarged view of the interdigital transducer structure provided with the weighted horizontal bar 55, wherein the length CB of the first weighted connecting bar 31 and the second weighted connecting bar 32 in parallel to the second direction is 0.02λ-0.25λ, the minimum distance Gap2 between each free end 24 and its nearest weighted connecting bar in parallel to the second direction is 0.02λ-0.4λ, and the minimum distance Gap1 between each free end 24 and its nearest bus bar in parallel to the second direction is 1λ-2λ; the distance Gap8 between the weighted horizontal bar 55 and the edge of the free end 24 to which it is close in the second direction is 0.005λ-0.03λ, and the length S of the weighted horizontal bar 55 in the second direction is 0.5λ-1λ;

[0148] λ is the wavelength of the surface acoustic wave propagating in the interdigital transducer structure.

[0149] In one embodiment, as shown in Figure 21, the weighted connecting strips include a first weighted connecting strip 31 and a second weighted connecting strip 32. The two adjacent first weighted connecting strips 31 along the first direction are staggered in the second direction so that the projections of the two adjacent first weighted connecting strips 31 in the first direction do not overlap; the two adjacent second weighted connecting strips 32 along the first direction are staggered in the second direction so that the projections of the two adjacent second weighted connecting strips 32 in the first direction do not overlap.

[0150] The present application further improves the influence of the weighted connecting strips on the acoustic wave propagation properties between the monopole region A and the interdigitated region B by coordinating the structure of the weighted connecting strips with staggered distribution, thereby further optimizing the suppression effect on the transverse mode.

[0151] In one embodiment, as shown in FIG22, which is an enlarged view of the interdigital transducer structure with staggered weighted connecting strips, the distance Gap8 between the weighted horizontal strip 55 and the edge of the free end 24 to which it is close in the second direction is 0.005λ-0.03λ, and the length S of the weighted horizontal strip 55 in the second direction is 0.5λ-1λ; the minimum distance Gap1 between each free end 24 and the bus bar closest to it in parallel to the second direction is 1λ-2λ; the distance between the two adjacent first weighted connecting strips 31 and the corresponding second electrode strips 22 along the first direction is 0.005λ-0.03λ. The minimum distances Gap5 and Gap6 in the second direction are 0.02λ-0.4λ and 0.1λ-0.6λ respectively, the minimum distances Gap5 and Gap6 between two adjacent second weighted connecting strips 32 along the first direction and their corresponding first electrode strips 21 in the second direction are 0.02λ-0.4λ and 0.1λ-0.6λ respectively, the lengths CB1 and CB2 of the first weighted connecting strip 31 and the second weighted connecting strip 32 parallel to the second direction are both 0.02λ-0.25λ; λ is the wavelength of the surface acoustic wave propagating in the interdigital transducer structure.

[0152] In one embodiment, the projections of two spaced-apart first weighted connecting strips 31 in the first direction overlap, and / or the projections of two spaced-apart second weighted connecting strips 32 in the first direction overlap.

[0153] In one embodiment, projections of two spaced-apart first weighted connecting strips 31 in the first direction do not overlap, and / or projections of two spaced-apart second weighted connecting strips 32 in the first direction do not overlap.

[0154] This embodiment can also be combined with any one or more combinations of any features in other embodiments to obtain a new structure, and the resulting structures are all within the scope of protection of this application.

[0155] Example 6:

[0156] This embodiment provides an IDT structure, which has the same features as the IDT structure in Embodiment 5, except that:

[0157] In the interdigital area B, an auxiliary weighting portion 56 is provided on the first electrode strip 21 and the second electrode strip 22 near the two weighting horizontal bars 55 ; the auxiliary weighting portion 56 is provided between the two weighting horizontal bars 55 , or the auxiliary weighting portion 56 is not provided between the two weighting horizontal bars 55 .

[0158] In one embodiment, as shown in FIG23 , the weighted connecting strips include a first weighted connecting strip 31 and a second weighted connecting strip 32 , wherein the projections of the first weighted connecting strip 31 in the first direction overlap, and the projections of the second weighted connecting strip 32 in the first direction overlap.

[0159] In one embodiment, as shown in FIG24 , which is an enlarged view of the interdigital transducer structure provided with the auxiliary weighted portion 56, the minimum distance Gap9 between the auxiliary weighted portion 56 and the weighted horizontal bar 55 adjacent to it in the second direction is 0.1λ-0.5λ, the minimum distance Gap3 between the free end of the weighted horizontal bar 55 and the edge of the electrode strip adjacent to it parallel to the first direction is 0.005λ-0.03λ, and the minimum distance Gap4 between each of the auxiliary weighted portions 56 and the edge of the electrode strip where each of the auxiliary weighted portions 56 is located parallel to the second direction is 0.005λ-0.03λ; the weighted horizontal bar 55 and the free end of the electrode strip adjacent to it parallel to the first direction is 0.005λ-0.03λ. The length S of the horizontal bar 55 in the second direction is 0.2λ-1λ, and the length Piston4 of the auxiliary weight portion 56 in the second direction is 0.2λ-1λ; the length CB of the first weight connection bar 31 and the second weight connection bar 32 parallel to the second direction are both 0.02λ-0.25λ, the minimum distance Gap2 between each free end 24 and the weight connection bar closest to it parallel to the second direction is 0.02λ-0.4λ, and the minimum distance Gap1 between each free end 24 and the bus bar closest to it parallel to the second direction is 1λ-2λ;

[0160] λ is the wavelength of the surface acoustic wave propagating in the interdigital transducer structure.

[0161] In one embodiment, the auxiliary weight portion 56 is disposed between two of the weighted horizontal bars 55 , or the auxiliary weight portion 56 is not disposed between two of the weighted horizontal bars 55 , that is, the order of the auxiliary weight portion 56 and the adjacent weighted horizontal bars 55 in the second direction can be swapped.

[0162] In one embodiment, as shown in Figure 25, the weighted connecting strips include a first weighted connecting strip 31 and a second weighted connecting strip 32. The two adjacent first weighted connecting strips 31 along the first direction are staggered in the second direction so that the projections of the two adjacent first weighted connecting strips 31 in the first direction do not overlap; the two adjacent second weighted connecting strips 32 along the first direction are staggered in the second direction so that the projections of the two adjacent second weighted connecting strips 32 in the first direction do not overlap.

[0163] The present application further improves the influence of the weighted connecting strips on the acoustic wave propagation properties between the monopole region A and the interdigitated region B by coordinating the structure of the weighted connecting strips with staggered distribution, thereby further optimizing the suppression effect on the transverse mode.

[0164] In one embodiment, as shown in FIG26, which is an enlarged view of the interdigital transducer structure of the staggered distribution of the weighted connecting strips, the minimum distance Gap9 between the auxiliary weighted portion 56 and the weighted horizontal bar 55 adjacent to it in the second direction is 0.1λ-0.5λ, the minimum distance Gap3 between the free end of the weighted horizontal bar 55 and the edge of the electrode strip adjacent to it parallel to the first direction is 0.005λ-0.03λ, and the minimum distance Gap4 between each of the auxiliary weighted portions 56 and the edge of the electrode strip parallel to the second direction where each of the auxiliary weighted portions 56 is located is 0.005λ-0.03λ; the length S of the weighted horizontal bar 55 in the second direction is 0.2λ-1λ, and the length Piston4 of the auxiliary weighted portion 56 in the second direction is 0.2λ-1λ; each of the free ends 24 and its The minimum distance Gap1 between the closest bus bars parallel to the second direction is 1λ-2λ; the minimum distances Gap5 and Gap6 between two adjacent first weighted connecting bars 31 and their corresponding second electrode bars 22 in the second direction are 0.02λ-0.4λ and 0.1λ-0.6λ respectively, the minimum distances Gap5 and Gap6 between two adjacent second weighted connecting bars 32 and their corresponding first electrode bars 21 in the second direction are 0.02λ-0.4λ and 0.1λ-0.6λ respectively, the lengths CB1 and CB2 of the first weighted connecting bar 31 and the second weighted connecting bar 32 parallel to the second direction are both 0.02λ-0.25λ; λ is the wavelength of the surface acoustic wave propagating in the interdigital transducer structure.

[0165] In one embodiment, the projections of two spaced-apart first weighted connecting strips 31 in the first direction overlap, and / or the projections of two spaced-apart second weighted connecting strips 32 in the first direction overlap.

[0166] In one embodiment, projections of two spaced-apart first weighted connecting strips 31 in the first direction do not overlap, and / or projections of two spaced-apart second weighted connecting strips 32 in the first direction do not overlap.

[0167] This embodiment can also be combined with any one or more combinations of any features in other embodiments to obtain a new structure, and the resulting structures are all within the scope of protection of this application.

[0168] Example 7:

[0169] This embodiment provides a filter structure, which includes any one of the interdigital transducer structures in Embodiments 1-6.

[0170] In one embodiment, as shown in FIG27 , the filter structure is a topological structure including a duplexer composed of nine interdigital transducer structures F8 - F16 , parallel resonators P1 - P6 , series resonators S1 - S7 , and inductors L3 - L6 .

[0171] Specifically, the interdigital transducer structure is usually applied to filtering at a receiving end frequency band within a filter structure.

[0172] In one embodiment, the filter structure further includes two reflection grating arrays 40, which are respectively arranged on both sides of the interdigital transducer structure along the first direction. Each of the reflection grating arrays 40 is composed of at least two metal reflection strips 42 and two auxiliary bus bars 41. The metal reflection strips 42 are parallel to the second direction and arranged along the first direction. The two ends of each metal reflection strip 42 in the second direction are respectively in contact with the two auxiliary bus bars 41. A reflection grating load structure is provided on the reflection grating array 40 at a position where the projection of the load structure of the interdigital transducer structure in the first direction coincides with that of the load structure.

[0173] The present application improves the reflection efficiency of the filter by providing a reflection grid array 40 .

[0174] In one embodiment, as shown in FIG2 , when the load structure of the interdigital transducer structure is the primary weighting portion 51, the reflective grating load structure is also the primary weighting portion 51, and the primary weighting portion 51 of the reflective grating array 40 is located on the metal reflective strip 42 at a position corresponding to the primary weighting portion 51 of the interdigital transducer structure in the first direction.

[0175] In the present application, a primary emphasis portion 51 corresponding to the interdigital transducing structure is provided at a corresponding position on the reflection grid array 40 , thereby further improving the reflection efficiency of the filter.

[0176] This embodiment can also be combined with any one or more combinations of any features in other embodiments to obtain a new structure, and the resulting structures are all within the scope of protection of this application.

[0177] Example 8:

[0178] This embodiment provides a filter structure. The filter structure has the same other features as the filter structure in Embodiment 7, except that:

[0179] As shown in Figure 11, when the primary weighting portion 51 of the interdigital transducer structure is at least two sub-weighting portions 52, each primary weighting portion 51 on the metal reflective strip 42 is also at least two sub-weighting portions 52 arranged along the second direction, and the sub-weighting portions 52 of the reflective grating array 40 are located at positions on the metal reflective strip 42 corresponding to the sub-weighting portions 52 of the interdigital transducer structure in the first direction.

[0180] In the present application, at least two sub-emphasis portions 52 corresponding to the interdigital transduction structure are provided at corresponding positions on the reflection grid array 40 , thereby further improving the reflection efficiency of the filter.

[0181] This embodiment can also be combined with any one or more combinations of any features in other embodiments to obtain a new structure, and the resulting structures are all within the scope of protection of this application.

[0182] Example 9:

[0183] This embodiment provides a filter structure. The filter structure has the same other features as the filter structure in Embodiment 7, except that:

[0184] As shown in FIG19 , when the load structure of the interdigital transducer structure is a weighted horizontal bar 55, the reflective grating load structure is also a weighted horizontal bar 55. The weighted horizontal bar 55 of the reflective grating array 40 is connected to the weighted horizontal bar 55 of the interdigital transducer structure and their projections in the first direction coincide with each other.

[0185] In the present application, weighted horizontal bars 55 corresponding to the interdigital transducing structure are provided at corresponding positions on the reflection grid array 40 to further improve the reflection efficiency of the filter.

[0186] This embodiment can also be combined with any one or more combinations of any features in other embodiments to obtain a new structure, and the resulting structures are all within the scope of protection of this application.

[0187] Example 10:

[0188] This embodiment provides a filter structure. The filter structure has the same other features as the filter structure in Embodiment 9, except that:

[0189] As shown in Figure 23, when the interdigital transducer structure is provided with an auxiliary weighting portion 56, the reflective grating array 40 is also provided with an auxiliary weighting portion 56. The auxiliary weighting portion 56 of the reflective grating array 40 is located at a position on the metal reflective strip 42 corresponding to the auxiliary weighting portion 56 of the interdigital transducer structure in the first direction.

[0190] In the present application, an auxiliary weighting portion 56 corresponding to the interdigital transducing structure is provided at a corresponding position on the reflection grid array 40 , thereby further improving the reflection efficiency of the filter.

[0191] This embodiment can also be combined with any one or more combinations of any features in other embodiments to obtain a new structure, and the resulting structures are all within the scope of protection of this application.

[0192] Example 11:

[0193] This embodiment provides an electronic device, which includes the filter structure described in any one of Embodiments 7-10.

[0194] In summary, the interdigital transducer structure, filter structure and electronic device of the present application can suppress the transverse mode within the RF filter band and reduce the loss by setting a weighted connecting strip in the monopole area and setting a load structure in the interdigital area; at the same time, the transverse mode can be further suppressed by staggering the weighted connecting strips; in addition, the suppression effect of the transverse mode can be further improved by coordinating the setting of the weighted connecting column, the sub-weighted part and the auxiliary weighted part; finally, the suppression effect of the transverse mode can be further improved by using the load structure as a weighted horizontal strip or a primary weighted part.

[0195] Therefore, the present invention effectively overcomes various shortcomings of the prior art and has high industrial utilization value.

[0196] The above embodiments are merely illustrative of the principles and effects of this application and are not intended to limit this application. Anyone skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of this application. Therefore, all equivalent modifications or alterations made by one of ordinary skill in the art without departing from the spirit and technical concepts disclosed in this application shall be covered by the claims of this application.

Claims

1. An interdigital transducer structure, characterized in that: The interdigital transducer structure comprises: a bus bar, an electrode bar, a weighted connecting bar and a load structure; The bus bar includes a first bus bar and a second bus bar arranged in parallel, and the electrode bar includes a first electrode bar and a second electrode bar; a plurality of the first electrode bars are arranged on the first bus bar, a plurality of the second electrode bars are arranged on the second bus bar, and the plurality of the first electrode bars and the plurality of the second electrode bars are arranged relatively spaced apart in a middle area between the first bus bar and the second bus bar; the end of the electrode bar connected to the bus bar is a connecting end, and the end of the electrode bar away from the connecting end is a free end; A direction parallel to the first bus bar is a first direction, a direction perpendicular to the first direction and parallel to the plane where the interdigital transducer structure is located is a second direction, and a third direction is perpendicular to both the first direction and the second direction; The middle region includes an interdigital region and a unipolar region not belonging to the interdigital region, wherein the interdigital region is a region formed between an edge of a free end of the first electrode strip and an edge of a free end of the second electrode strip; The weighted connecting bar is located in the monopolar region, and the weighted connecting bar is located between the free end of the first electrode bar and the second bus bar, and / or between the free end of the second electrode bar and the first bus bar; There is a preset distance in the second direction between the projection of the load structure on the electrode strip and the edge of the free end of the electrode strip.

2. The interdigital transducer structure according to claim 1, characterized in that: The load structure is a primary weighting part, which is respectively located on the surface of the free end of the first electrode strip, and / or the surface of the second electrode strip at a position corresponding to the free end of the first electrode strip in the first direction, and / or the surface of the free end of the second electrode strip, and / or the surface of the first electrode strip at a position corresponding to the free end of the second electrode strip in the first direction.

3. The interdigital transducer structure according to claim 2, characterized in that: Each of the primary weight portions includes at least two sub-weight portions arranged along the second direction.

4. The interdigital transducer structure according to claim 2, characterized in that: The weighted connecting bar includes a first weighted connecting bar and a second weighted connecting bar, the second weighted connecting bar is connected to the second bus bar at a position corresponding to the first electrode bar along the second direction through a weighted connecting column, and the first weighted connecting bar is connected to the first bus bar at a position corresponding to the second electrode bar along the second direction through a weighted connecting column.

5. The interdigital transducer structure according to claim 4, characterized in that: A secondary weight portion is arranged on each of the weighted connecting columns.

6. The interdigital transducer structure according to claim 1, characterized in that: The load structure is a weighted horizontal bar, which is parallel to the first direction. One of the weighted horizontal bars is arranged on the surface of the free end of the first electrode bar in the second direction, and the other weighted horizontal bar is arranged on the surface of the free end of the second electrode bar in the second direction.

7. The interdigital transducer structure according to claim 6, characterized in that: In the interdigital area, an auxiliary weighting portion is provided on the first electrode strip and the second electrode strip near the two weighting horizontal strips; the auxiliary weighting portion is provided between the two weighting horizontal strips, or the auxiliary weighting portion is not provided between the two weighting horizontal strips.

8. The interdigital transducer structure according to any one of claims 1 to 7, characterized in that: The weighted connecting strips include a first weighted connecting strip and a second weighted connecting strip, the projections of the first weighted connecting strip in the first direction overlap, and the projections of the second weighted connecting strip in the first direction overlap; The lengths of the first weighted connecting strip and the second weighted connecting strip in parallel to the second direction are both 0.02λ-0.25λ, the minimum distance between each free end and the weighted connecting strip closest to it in parallel to the second direction is 0.02λ-0.4λ, and the minimum distance between each free end and the bus bar closest to it in parallel to the second direction is 1λ-2λ; When the load structure is a primary weighting part, the projection of each primary weighting part on the plane where the interdigital transducer structure is located is located inside the projection of the electrode strip where each primary weighting part is located on the plane where the interdigital transducer structure is located, the length of the electrode strip where the primary weighting part is located in the first direction is greater than the length of the primary weighting part in the first direction, and the length of each primary weighting part parallel to the second direction is 0.5λ-1λ; λ is the wavelength of the surface acoustic wave propagating in the interdigital transducer structure.

9. The interdigital transducer structure according to any one of claims 1 to 7, characterized in that: The weighted connecting strips include a first weighted connecting strip and a second weighted connecting strip, and two adjacent first weighted connecting strips along the first direction are staggered in the second direction so that the projections of the two adjacent first weighted connecting strips in the first direction do not overlap; Two adjacent second weighted connecting strips along the first direction are staggeredly distributed in the second direction, so that the projections of the two adjacent second weighted connecting strips in the first direction do not overlap.

10. The interdigital transducer structure according to claim 9, characterized in that: The minimum distances between two adjacent first weighted connecting strips along the first direction and their corresponding second electrode strips in the second direction are 0.02λ-0.4λ and 0.1λ-0.6λ respectively, the minimum distances between two adjacent second weighted connecting strips along the first direction and their corresponding first electrode strips in the second direction are 0.02λ-0.4λ and 0.1λ-0.6λ respectively, the lengths of the first weighted connecting strip and the second weighted connecting strip parallel to the second direction are both 0.02λ-0.25λ; λ is the wavelength of surface acoustic waves propagating in the interdigital transducer structure.

11. A filter structure, comprising the interdigital transducer structure according to any one of claims 1 to 10.

12. The filter structure according to claim 11, characterized in that The filter structure also includes two reflection grating arrays, which are respectively arranged on both sides of the interdigital transducer structure along the first direction, each of the reflection grating arrays is composed of at least two metal reflection bars and two auxiliary bus bars, the metal reflection bars are parallel to the second direction and arranged along the first direction, and each of the metal reflection bars is respectively in contact with the two auxiliary bus bars at two ends in the second direction, and a reflection grating load structure is arranged on the reflection grating array at a position where the projection of the load structure of the interdigital transducer structure in the first direction coincides.

13. The filter structure according to claim 12, characterized in that: When the load structure of the interdigital transducer structure is a primary weighting part, the reflective grating load structure is also a primary weighting part, and the primary weighting part of the reflective grating array is located at a position on the metal reflective strip corresponding to the primary weighting part of the interdigital transducer structure in the first direction.

14. The filter structure according to claim 13, characterized in that: When the primary weighting portion of the interdigital transduction structure is at least two sub-weighting portions, each primary weighting portion on the metal reflection strip is also at least two sub-weighting portions arranged along the second direction, and the sub-weighting portions of the reflection grating array are located at positions on the metal reflection strip corresponding to the sub-weighting portions of the interdigital transduction structure in the first direction.

15. The filter structure according to claim 12, characterized in that: When the load structure of the IDT structure is a weighted bar, the reflective grating load structure is also a weighted bar. The weighted bar of the reflective grating array is connected to the weighted bar of the IDT structure and their projections in the first direction overlap.

16. The filter structure according to claim 15, characterized in that When the interdigital transducing structure is provided with an auxiliary weighting portion, the reflective grating array is also provided with an auxiliary weighting portion, and the auxiliary weighting portion of the reflective grating array is located at a position on the metal reflective strip corresponding to the auxiliary weighting portion of the interdigital transducing structure in the first direction.

17. An electronic device, comprising the filter structure according to any one of claims 11 to 16.

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