Resonator, filter, and electronic device

Abstract

The invention discloses a resonator, a filter and an electronic device, and belongs to the technical field of semiconductors. The resonator comprises a substrate, the substrate comprises an electrode finger area, and the electrode finger area comprises a main body area and edge areas located on the two opposite sides of the main body area in the first direction; the piezoelectric structure is located on one side, in the second direction, of the substrate, the piezoelectric structure comprises a first piezoelectric layer at least located in the main body area and a second piezoelectric layer at least located in the edge area, and the first piezoelectric layer and the second piezoelectric layer both comprise anisotropic dielectric materials; the crystal orientations of the first piezoelectric layer and the second piezoelectric layer are different; the electrode layer is located on the side, away from the substrate, of the piezoelectric structure. According to the invention, a spurious mode can be suppressed, and the performance of the resonator is improved.

Description

Technical Field

[0001] The present application belongs to the field of semiconductor technology, and in particular relates to a resonator, a filter and an electronic device. Background Art

[0002] Resonators are widely used in mobile communication devices, with advantages such as low insertion loss, wide bandwidth, small size, low cost, and mass production. However, when the main mode is excited, the resonator will also generate unnecessary spurious modes (such as spurious generated by the lateral mode perpendicular to the main mode), and the spurious modes will affect the performance of the resonator. Summary of the invention

[0003] The present application aims to solve at least one of the technical problems existing in the prior art. To this end, the present application proposes a resonator, a filter and an electronic device, which can suppress spurious modes and improve the performance of the resonator.

[0004] In a first aspect, the present application provides a resonator, comprising:

[0005] A substrate, comprising an electrode finger region, wherein the electrode finger region comprises a main body region and edge regions located on two opposite sides of the main body region along a first direction;

[0006] A piezoelectric structure is located on one side of the substrate along the second direction, the piezoelectric structure includes a first piezoelectric layer at least located in the main area and a second piezoelectric layer at least located in the edge area, the first piezoelectric layer and the second piezoelectric layer both include anisotropic dielectric materials, and the second piezoelectric layer has a different crystal orientation from the first piezoelectric layer; the second direction is the thickness direction of the substrate, and the second reverse direction is perpendicular to the first direction;

[0007] The electrode layer is located in the electrode finger region and on a side of the piezoelectric structure facing away from the substrate.

[0008] According to the resonator of the present application, a piezoelectric structure is set up so that the piezoelectric structure includes a first piezoelectric layer located in the main area and a second piezoelectric layer located in the edge area, and the first piezoelectric layer and the second piezoelectric layer both include anisotropic dielectric materials, and the crystal orientations of the first piezoelectric layer and the second piezoelectric layer are different, so as to directionally scatter the stray mode transmitted to the edge area to the substrate, avoid the stray mode from being reflected back to the electrode finger area, thereby ensuring the main mode propagation characteristics while suppressing the stray mode and improving the performance of the resonator.

[0009] According to an embodiment of the present application, the dielectric anisotropy of the first piezoelectric layer is greater than the dielectric anisotropy of the second piezoelectric layer.

[0010] According to an embodiment of the present application, the materials of the first piezoelectric layer and the second piezoelectric layer are the same or different, and the crystal cutting angles of the first piezoelectric layer and the second piezoelectric layer are the same or different.

[0011] According to one embodiment of the present application, the orthographic projection of a surface of the first piezoelectric layer facing away from the substrate on the substrate coincides with the main region.

[0012] According to an embodiment of the present application, the second piezoelectric layer is located on at least one of two opposite sides of the first piezoelectric layer along the first direction.

[0013] According to an embodiment of the present application, the interface between the first piezoelectric layer and the second piezoelectric layer is perpendicular to the first direction or inclined toward the main region.

[0014] According to one embodiment of the present application, the interface between the first piezoelectric layer and the second piezoelectric layer includes at least one of a plane, a curved surface, and a folded line surface.

[0015] According to one embodiment of the present application, the first piezoelectric layer and the second piezoelectric layer are distributed along the second direction;

[0016] The second piezoelectric layer is located in the edge region and the main region.

[0017] According to one embodiment of the present application, the first piezoelectric layer is located between the second piezoelectric layer and the electrode layer.

[0018] According to one embodiment of the present application, the second piezoelectric layer is a single-layer structure or a stacked-layer structure.

[0019] According to an embodiment of the present application, the substrate further includes busbar regions located on opposite sides of the electrode finger region along the first direction, and a gap region located between the electrode finger region and the busbar region;

[0020] The second piezoelectric layer is also located in the gap region.

[0021] According to one embodiment of the present application, the second piezoelectric layer is also located in the busbar region.

[0022] According to one embodiment of the present application, the resonator further includes a dielectric layer;

[0023] The dielectric layer is located between the substrate and the electrode layer, and is located on at least one of two opposite sides of the piezoelectric structure along the first direction.

[0024] In a second aspect, the present application provides a filter, comprising the resonator as described in the first aspect above.

[0025] In a third aspect, the present application provides an electronic device, comprising the filter as described in the second aspect above.

[0026] The above one or more technical solutions in the embodiments of the present application have at least one of the following technical effects:

[0027] By setting a piezoelectric structure, the piezoelectric structure includes a first piezoelectric layer located in the main area and a second piezoelectric layer located in the edge area, and the first piezoelectric layer and the second piezoelectric layer both include anisotropic dielectric materials, and the crystal orientations of the first piezoelectric layer and the second piezoelectric layer are different, so as to directionally scatter the stray mode transmitted to the edge area to the substrate, avoid the stray mode from being reflected back to the electrode finger area, thereby ensuring the main mode propagation characteristics while suppressing the stray mode and improving the performance of the resonator.

[0028] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which:

[0030] Figure 1 It is one of the structural schematic diagrams of the resonator provided in the embodiment of the present application;

[0031] Figure 2 is a top view of a resonator provided in an embodiment of the present application;

[0032] Figure 3 It is one of the principle schematic diagrams of the resonator provided in the embodiment of the present application;

[0033] Figure 4 It is one of the curve relationship diagrams of frequency and conductance of the second piezoelectric layer in the resonator provided in the embodiment of the present application at different crystal orientations;

[0034] Figure 5 This is one of the curve relationship diagrams of frequency and conductance of the resonator provided in the embodiment of the present application when the edge region width is different;

[0035] Figure 6 This is the second graph of the relationship between frequency and conductance of the resonator provided in the embodiment of the present application when the edge region width is different;

[0036] Figure 7 This is one of the comparison diagrams of the relationship between the frequency and admittance of the resonator in the embodiment of the present application and the related art;

[0037] Figure 8 This is the second comparison diagram of the relationship between the frequency and admittance of the resonator in the embodiment of the present application and the related art;

[0038] Fig. 9 This is the second structural schematic diagram of the resonator provided in the embodiment of the present application;

[0039] Fig.10 This is the third structural schematic diagram of the resonator provided in the embodiment of the present application;

[0040] Fig.11 This is the second graph of the relationship between frequency and conductance of the second piezoelectric layer in the resonator provided in the embodiment of the present application when the crystal orientation is different;

[0041] Fig.12 This is the fourth structural schematic diagram of the resonator provided in the embodiment of the present application;

[0042] Fig.13 This is the fifth structural diagram of the resonator provided in the embodiment of the present application;

[0043] Fig.14 This is the sixth structural schematic diagram of the resonator provided in the embodiment of the present application;

[0044] Fig.15 This is the seventh structural diagram of the resonator provided in the embodiment of the present application;

[0045] Fig.16 This is the eighth structural schematic diagram of the resonator provided in the embodiment of the present application;

[0046] Fig.17 This is the ninth structural schematic diagram of the resonator provided in the embodiment of the present application. DETAILED DESCRIPTION

[0047] The embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as limiting the present application.

[0048] The resonator, filter and electronic device provided by the embodiments of the present application are described below with reference to the accompanying drawings.

[0049] Figure 1 A schematic diagram of the structure of a resonator provided in an embodiment of the present application. The resonator may be a surface acoustic wave (SAW) resonator or a bulk acoustic wave (BAW) resonator. For example, the resonator may be a solid-state mounted resonator (SMR) resonator, a transversely excited bulk acoustic wave resonator (XBAR), a shear wave resonator (YBAR), a POI (piezoelectric film on insulator) resonator, etc.

[0050] like Figure 1As shown, the resonator includes a substrate 1, a piezoelectric structure 2 and an electrode layer 3. The substrate 1, the piezoelectric structure 2 and the electrode layer 3 are arranged in sequence along a second direction Y, and the second direction Y is a thickness direction of the substrate 1.

[0051] The substrate 1 includes a device region, and the device region is used to set a device (such as a surface acoustic wave device or a bulk acoustic wave device). The device region includes an electrode finger region 10, and the electrode finger region 10 includes a main region 20 and an edge region 30 located on opposite sides of the main region 20 along a first direction X. The first direction X is perpendicular to the second direction Y. In some embodiments, the device region may also include a busbar region 50 located on opposite sides of the electrode finger region 10 along the first direction X, and a gap region 40 located between the electrode finger region 10 and the busbar region 50, that is, the busbar region 50 is located on the side of the edge region 30 away from the main region 20, and the gap region 40 is located between the edge region 30 and the busbar region 50.

[0052] Combination Figure 2 As shown, the edge region 30 may include a first edge sub-region 30a and a second edge sub-region 30b, and the first edge sub-region 30a and the second edge sub-region 30b are respectively located at opposite sides of the main body region 20 along the first direction X. The busbar region 50 may include a first busbar sub-region 50a and a second busbar sub-region 50b, and the first busbar sub-region 50a is located at a side of the first edge sub-region 30a away from the main body region 20, and the second busbar sub-region 50b is located at a side of the second edge sub-region 30b away from the main body region 20. The gap region 40 may include a first gap sub-region 40a and a second gap sub-region 40b, and the first gap sub-region 40a is located between the first edge sub-region 30a and the first busbar sub-region 50a, and the second gap sub-region 40b is located between the second edge sub-region 30b and the second busbar sub-region 50b.

[0053] In some embodiments, Figure 1 As shown, the base 1 may include a substrate 11 and a support layer 12. The support layer 12 is located on one side of the substrate 11 along the second direction Y. The substrate 1 may include a silicon substrate, etc. The support layer 12 may include silicon oxide, such as silicon dioxide. According to actual needs, the base 1 may also include other film layers, which are not specifically limited here.

[0054] The piezoelectric structure 2 is located on one side of the substrate 1 along the second direction Y. When the substrate 1 includes a substrate 11 and a support layer 12, the piezoelectric structure 2 is located on the side of the support layer 12 away from the substrate 11. The piezoelectric structure 2 is at least located in the electrode finger region 10. The piezoelectric structure 2 may be located only in the electrode finger region 10, or in the electrode finger region 10 and the gap region 40, or in the electrode finger region 10, the gap region 40, and the busbar region 50.

[0055] The piezoelectric structure 2 includes a first piezoelectric layer 21 and a second piezoelectric layer 22. The first piezoelectric layer 21 is at least located in the main region 20, that is, the first piezoelectric layer 21 can be located only in the main region 20, or in the main region 20 and the edge region 30, or in the main region 20, the edge region 30 and the gap region 40. Figure 2 As shown, when the first piezoelectric layer 21 is located in the edge region 30, the first piezoelectric layer 21 can be located in the first edge sub-region 30a and / or the second edge sub-region 30b. When the first piezoelectric layer 21 is located in the gap region 40, the first piezoelectric layer 21 can be located in the first gap sub-region 40a and / or the second gap sub-region 40b.

[0056] The second piezoelectric layer 22 is at least located in the edge region 20, that is, the second piezoelectric layer 22 can be located only in the edge region 20, or in the edge region 30 and the main region 20, or in the edge region 30 and the gap region 40, or in the edge region 30, the gap region 40 and the busbar region 50, etc. Figure 2 As shown, when the second piezoelectric layer 22 is located in the edge region 30, the second piezoelectric layer 22 can be located in the first edge sub-region 30a and / or the second edge sub-region 30b. When the second piezoelectric layer 22 is located in the gap region 40, the second piezoelectric layer 22 can be located in the first gap sub-region 40a and / or the second gap sub-region 40b. When the second piezoelectric layer 22 is located in the busbar region 50, the second piezoelectric layer 22 can be located in the first busbar sub-region 50a and / or the second busbar sub-region 50b.

[0057] The first piezoelectric layer 21 and the second piezoelectric layer 22 both include anisotropic dielectric materials. The materials of the first piezoelectric layer 21 and the second piezoelectric layer 22 may be the same or different. For example, the first piezoelectric layer 21 and the second piezoelectric layer 22 may both include lithium tantalate (LiTaO3, LT for short). The crystal cutting angles of the first piezoelectric layer 21 and the second piezoelectric layer 22 may be the same or different. The crystal orientations of the first piezoelectric layer 21 and the second piezoelectric layer 22 are different.

[0058] The electrode layer 3 is located on the side of the piezoelectric structure 2 facing away from the substrate 1 , and the electrode layer 3 is located in the electrode finger region 10 , the gap region 40 and the busbar region 50 , that is, the electrode layer 3 is located in the device region.

[0059] In some embodiments, in combination Figure 2As shown, the electrode layer 3 includes a plurality of electrode fingers, a first busbar 33 and a second busbar 34. The first busbar 33 and the second busbar 34 are both located in the busbar area 50 and extend along the third direction Z, and the third direction Z is perpendicular to the first direction X and the second direction Y, respectively. The first busbar 33 is located in the first busbar sub-area 50a, and the second busbar 34 is located in the second busbar sub-area 50b. The plurality of electrode fingers include first electrode fingers 31 and second electrode fingers 32 that are alternately and spaced along the third direction Z. The first electrode fingers 31 and the second electrode fingers 32 are both located in the electrode finger area 10 and extend along the first direction X. The first electrode finger 31 extends from the electrode finger area 10 along the first direction X to the first gap sub-area 40a, and is connected to the first busbar 33, that is, the first electrode finger 31 is located in the electrode finger area 10 and the first gap sub-area 40a. The second electrode fingers 32 extend from the electrode finger region 10 along the first direction X to the second gap sub-region 40 b and are connected to the second bus bar 34 , that is, the second electrode fingers 32 are located in the electrode finger region 10 and the second gap sub-region 40 b .

[0060] The number of the first electrode fingers 31 and the second electrode fingers 32 may be the same. The sizes (including length and width, etc.) of the first electrode fingers 31 and the second electrode fingers 32 may be the same. The materials of the first electrode fingers 31 and the second electrode fingers 32 may both include metal materials such as copper and aluminum. The first busbar 33 and the second busbar 34 may be used as connecting wires connecting adjacent resonators or connecting wires connecting the package side. The materials of the first busbar 33 and the second busbar 34 may both include metal materials such as copper and aluminum.

[0061] The transverse mode TM propagates in the transverse direction (perpendicular to the main mode), and the TM energy distribution is formed by the standing wave propagating in the transverse direction, and its reflection center is located in the edge region 30. Generally, a few TMs with frequencies near the resonance have good energy confinement in the main region 10, and their energy does not propagate to the gap region 40, resulting in difficulty in suppressing TM spurious when the main mode exists.

[0062] In this embodiment, the first piezoelectric layer 21 and the second piezoelectric layer 22 are arranged so that the first piezoelectric layer 21 is at least located in the main area 20, and the second piezoelectric layer 22 is at least located in the edge area 30, and the first piezoelectric layer 21 and the second piezoelectric layer 22 both include anisotropic dielectric materials, and the crystal orientations of the first piezoelectric layer 21 and the second piezoelectric layer 22 are different, so that the stray mode transmitted to the edge area 30 can be directionally scattered to the gap area 40, and attenuated in the gap area 40 to avoid returning to the main area 20, thereby suppressing the stray mode while ensuring the main mode transmission characteristics, improving the performance of the resonator, and there is no need to change the size of the resonator or the structure of the electrode layer. Moreover, this embodiment can be used in combination with other stray suppression methods (such as piston mode IDT, slowness curve optimization), etc.) to further improve the stray suppression effect.

[0063] like Figure 3 As shown in FIG. 1 , when TM propagates in the first piezoelectric layer 21 and the second piezoelectric layer 22, the scattering direction of TM at the interface between the two layers can be changed. Based on Snell's law and considering the anisotropic material properties, the scattering angle β can be calculated as f(C ij ). Among them, C ij is a matrix related to the stiffness constant of the material and the crystal orientation. By adjusting the material and crystal orientation of the first piezoelectric layer 21 and the second piezoelectric layer 22, the scattering angle β is between 0 and 90°, and the TM transmitted to the edge region 30 is directionally scattered into the substrate 1, avoiding the TM from returning to the main region 20, thereby suppressing the stray mode.

[0064] This embodiment can optimize the crystal orientation of the second piezoelectric layer 22 based on the three-dimensional finite element model (3D FEM model) of the resonator. For example, the substrate 11 includes silicon, the support layer 12 includes silicon dioxide, the electrode layer 3 includes aluminum, the first piezoelectric layer 21 and the second piezoelectric layer 22 both include LT materials, the crystal orientation of the first piezoelectric layer 21 is 50° Y-cut, and the width of the edge region 30 (the width L of the first edge sub-region 30a and the width L of the second edge sub-region 30b) is fixed to a wavelength λ. The crystal orientation (Y-cut rotation angle) of the second piezoelectric layer 22 is adjusted between 0 and 90°, and the conductivity characteristics of the resonator are detected respectively, such as Figure 4 As shown. It can be seen that different crystal orientations of the second piezoelectric layer 22 have different effects on the output impedance characteristics and stray suppression of the resonator. When the crystal orientation of the second piezoelectric layer 22 is 20° Y-cut and 70° Y-cut, the resonator has a lateral stray suppression effect.

[0065] The material anisotropy of the second piezoelectric layer 22 can control the direction of the scattered stray mode in the edge region. By adjusting the crystal orientation of the second piezoelectric layer 22 to the optimal value, the stray mode can be completely suppressed. In this embodiment, the material and crystal orientation of the first piezoelectric layer 21 can be optimized first to improve the resonator performance (such as improving k2, Q value, TCF, etc.). Then, the material and crystal orientation of the second piezoelectric layer 22 are optimized to achieve a good stray suppression effect.

[0066] When the crystal orientation of the second piezoelectric layer 22 is 70° Y-cut, the width of the edge region 30 (the width L of the first edge sub-region 30a and the width L of the second edge sub-region 30b) is adjusted between 0.2λ and 1.8λ, and the conductivity characteristics of the resonator are detected respectively, such as Figure 5 It can be seen that when the crystal orientation of the second piezoelectric layer 22 is 70° Y-cut, L=0.8λ, and the resonator has a good stray suppression effect.

[0067] When the crystal orientation of the second piezoelectric layer 22 is 20° Y-cut, the width of the edge region 30 (the width L of the first edge sub-region 30a and the width L of the second edge sub-region 30b) is adjusted between 0.2λ and 1.8λ, and the conductivity characteristics of the resonator are detected respectively, such as Figure 6 It can be seen that when the crystal orientation of the second piezoelectric layer 22 is 20° Y-cut, L=1λ, and the resonator has a good stray suppression effect.

[0068] like Figure 7 and Figure 8 As shown, when the width of the edge region 30 (the width L of the first edge sub-region 30a and the width L of the second edge sub-region 30b) are 0.2λ and 0.8λ respectively, the admittance characteristics of the resonator provided by the related art and the present embodiment are compared respectively. Among them, the resonator in the related art only has one piezoelectric layer between the substrate and the electrode layer, and the piezoelectric layer is located in the electrode finger region, the gap region and the busbar region. The crystal orientation of the piezoelectric layer in the related art is 50°Y-cut, and the crystal orientation of the first piezoelectric layer 21 in the present embodiment is 50°Y-cut, and the crystal orientation of the second piezoelectric layer 22 is 70°Y-cut (as shown in FIG. Figure 7 as shown) and 20°Y cut (as shown Figure 8 As shown). It can be seen that compared with the related art, this embodiment effectively suppresses the stray mode. In addition, when L = 0.8λ, this embodiment has a better stray suppression effect. When the crystal orientation of the second piezoelectric layer 22 is 20°Y-cut, this embodiment shows a stray suppression effect near the resonance frequency, but high-order strays still exist.

[0069] While optimizing the crystal orientation of the second piezoelectric layer 22 and the width of the edge region 30, this embodiment can also optimize the material and crystal cutting angle of the second piezoelectric layer 22, further improving the stray suppression effect of the resonator, and improving the Q value of the resonator, better limiting the acoustic energy, and reducing the scattering loss of the main mode.

[0070] In some embodiments, the dielectric anisotropy of the first piezoelectric layer 21 is greater than the dielectric anisotropy of the second piezoelectric layer 22. The second piezoelectric layer 22 may be made of a high dielectric anisotropy material, such as Qz, ALN, SiC, Si, Al2O3, and the like.

[0071] In some embodiments, the orthographic projection of the surface of the first piezoelectric layer 21 facing away from the substrate 1 on the substrate 1 coincides with the main area 20 , and the orthographic projection of the surface of the first piezoelectric layer 21 close to the substrate 1 on the substrate 1 at least covers the main area 20 , so that the first piezoelectric layer 21 is at least located in the main area 20 .

[0072] In some embodiments, Figure 1As shown, the piezoelectric structure 2 is located in all electrode finger regions 10 , all gap regions 40 and all busbar regions 50 , wherein the first piezoelectric layer 21 is at least located in the main region 20 , and the second piezoelectric layer 22 is at least located in the edge region 30 , the gap region 40 and the busbar region 50 .

[0073] In some embodiments, the piezoelectric structure 2 is located only in the electrode finger region 10, or the piezoelectric structure 2 is located in the electrode finger region 10 and part of other regions (at least part of the gap region 40 or the gap region 40 and part of the busbar region 50). Fig. 9 and Fig.10 As shown, the resonator further includes a dielectric layer 4. The dielectric layer 4 is located between the substrate 1 and the electrode layer 3, and the dielectric layer 4 is located on at least one of the two opposite sides of the piezoelectric structure 2 along the first direction X, that is, the dielectric layer 4 is located in the area not covered by the piezoelectric structure 2. The TM velocity in the dielectric layer 4 is less than the TM velocity in the piezoelectric structure 2. The dielectric layer 4 may include one or more combinations of SiO2, Si3N4, Al2O3, Ta2O5, ALN, SiC, etc.

[0074] For example Fig. 9 As shown, the piezoelectric structure 2 is located in the electrode finger region 10, and the dielectric layer 4 is located in the gap region 40 and the busbar region 50; for example Fig.10 As shown, the piezoelectric structure 2 is located in the electrode finger area 10 and a part of the gap area 40, and the dielectric layer 4 is located in the remaining gap area 40 and the busbar area 50; the piezoelectric structure 2 is located in the electrode finger area 10 and the gap area 40, and the dielectric layer 4 is located in the busbar area 50; the piezoelectric structure 2 is located in the electrode finger area 10, the gap area 40 and a part of the busbar area 50, and the dielectric layer 4 is located in the remaining busbar area 50.

[0075] In this embodiment, a dielectric layer 4 is provided on at least one of the two opposite sides of the piezoelectric structure 2 along the first direction X, and the crystal orientation of the second piezoelectric layer 22 is adjusted, so that high-order TM spurious can be leaked to the gap area 40 and the busbar area 50, and low-order spurious can have good energy confinement in the electrode finger area 10, thereby effectively reducing high-order spurious and low-order spurious.

[0076] like Fig.11 As shown, the crystal orientation (Y-section rotation angle) of the second piezoelectric layer 22 is adjusted between 0 and 90 degrees, and the conductivity characteristics of the resonator are detected respectively. It can be seen that when the crystal orientation of the second piezoelectric layer 22 is close to 90 degrees Y-section, high-order spurious can be effectively reduced.

[0077] In some embodiments, Figure 1 , Fig. 9 and Fig.10 As shown, the second piezoelectric layer 22 may be a single-layer structure. Fig.12 and Fig.13As shown, the second piezoelectric layer 22 can be a laminated structure. In the case where the second piezoelectric layer 22 is a laminated structure, the second piezoelectric layer 22 includes multiple film layers, and the number of film layers is not specifically limited. The materials, crystal cutting angles, and crystal orientations of the multiple film layers can be the same or different. The stacking direction of the multiple film layers can be parallel to the first direction X, or can intersect with the first direction X, which is not specifically limited here.

[0078] like Fig.12 and Fig.13 As shown, the second piezoelectric layer 22 may include a first film layer 221 and a second film layer 222. Fig.12 As shown, the stacking direction of the first film layer 221 and the second film layer 222 is parallel to the first direction X. Fig.13 As shown, the stacking direction of the first film layer 221 and the second film layer 222 intersects with the first direction X.

[0079] In this embodiment, the second piezoelectric layer 22 is a laminated structure, and the acoustic characteristics of the edge area can be adjusted according to different film layers to further improve the suppression effect of the stray mode.

[0080] In some embodiments, the first piezoelectric layer 21 and the second piezoelectric layer 22 are distributed along the first direction X. Figure 1 As shown, the second piezoelectric layer 22 is located on at least one of the two opposite sides of the first piezoelectric layer 21 along the first direction X. The first piezoelectric layer 21 is at least located in the main area 20, and the second piezoelectric layer 22 is at least located in the edge area 30. In the case where the second piezoelectric layer 22 is located in the edge area 30, the second piezoelectric layer 22 is located in the first edge sub-area 30a and / or the second edge sub-area 30b.

[0081] For example Figure 1 , Fig.12 and Fig.13 As shown, the second piezoelectric layer 22 is located on two opposite sides of the first piezoelectric layer 21 along the first direction X, and the first piezoelectric layer 21 is located in the main area 20, and the second piezoelectric layer 22 is located in the edge area 30, the gap area 40 and the busbar area 50. Fig.14 , Fig.15 and Fig.16 As shown, the second piezoelectric layer 22 is located on opposite sides of the first piezoelectric layer 21 along the first direction X, and the first piezoelectric layer 21 is located in the main area 20 and the edge area 30, and the second piezoelectric layer 22 is located in the edge area 30, the gap area 40 and the busbar area 50. Fig.10 As shown, the second piezoelectric layer 22 is located at two opposite sides of the first piezoelectric layer 21 along the first direction X, and the first piezoelectric layer 21 is located in the main area 20 , and the second piezoelectric layer 22 is located in the edge area 30 and the gap area 40 .

[0082] In some embodiments, when the first piezoelectric layer 21 and the second piezoelectric layer 22 are distributed along the first direction X, the interface between the first piezoelectric layer 21 and the second piezoelectric layer 22 is perpendicular to the first direction X or inclined toward the main region 20 .

[0083] The orthographic projection of the surface of the first piezoelectric layer 21 facing away from the substrate 1 on the substrate 1 coincides with the main area 20. When the interface between the first piezoelectric layer 21 and the second piezoelectric layer 22 is perpendicular to the first direction X, as shown in FIG. Figure 1 , Fig. 9 , Fig.10 and Fig.12 As shown, the orthographic projection of the surface of the first piezoelectric layer 21 close to the substrate 1 on the substrate 1 coincides with the main region 20, that is, the first piezoelectric layer 21 is located in the main region 20; when the interface between the first piezoelectric layer 21 and the second piezoelectric layer 22 is inclined toward the main region 20, as shown in Figures 14 to 16 As shown, the orthographic projection of the surface of the first piezoelectric layer 21 close to the substrate 1 on the substrate 1 can cover the main area 20 and at least part of the edge area 30 (that is, the first piezoelectric layer 21 is located in the main area 20 and at least part of the edge area 30), or can cover the main area 20, the edge area 30 and at least part of the gap area 40 (that is, the first piezoelectric layer 21 is located in the main area 20, the edge area 30 and at least part of the gap area 40).

[0084] In this embodiment, the interface between the first piezoelectric layer 21 and the second piezoelectric layer 22 is inclined toward the main region 20, which can further improve the scattering effect of the stray mode transmitted to the edge region to the substrate 1, thereby further suppressing the stray mode.

[0085] In some embodiments, when the first piezoelectric layer 21 and the second piezoelectric layer 22 are distributed along the first direction X, the interface between the first piezoelectric layer 21 and the second piezoelectric layer 22 may include at least one of a plane, a curved surface, and a folded line surface.

[0086] like Figure 1 , Fig. 9 , Fig.10 and Fig.12 As shown, the second piezoelectric layer 22 is located on opposite sides of the first piezoelectric layer 21 along the first direction X, and the interface between the first piezoelectric layer 21 and the second piezoelectric layer 22 is a vertical plane (perpendicular to the first direction X). Fig.14 As shown, the second piezoelectric layer 22 is located on opposite sides of the first piezoelectric layer 21 along the first direction X, and the interface between the first piezoelectric layer 21 and the second piezoelectric layer 22 is an inclined plane (inclined toward the main region 20). Fig.15As shown, the second piezoelectric layer 22 is located on opposite sides of the first piezoelectric layer 21 along the first direction X, and the interface between the first piezoelectric layer 21 and the second piezoelectric layer 22 is an inclined fold line surface (inclined toward the main area 20). Fig.16 As shown, the second piezoelectric layer 22 is located on two opposite sides of the first piezoelectric layer 21 along the first direction X, and the interface between the first piezoelectric layer 21 and the second piezoelectric layer 22 is an inclined arc surface (inclined toward the main body area 20).

[0087] In some embodiments, Fig.17 As shown, the first piezoelectric layer 21 and the second piezoelectric layer 22 are distributed along the second direction Y. The first piezoelectric layer 21 can be located between the second piezoelectric layer 22 and the substrate 1, and the surface of the first piezoelectric layer 21 close to the substrate 1 is flush with the surface of the second piezoelectric layer 22 close to the substrate 1. The first piezoelectric layer 21 can also be located between the second piezoelectric layer 22 and the electrode layer 3, and the surface of the first piezoelectric layer 21 close to the electrode layer 3 is flush with the surface of the second piezoelectric layer 22 close to the electrode layer 2. The first piezoelectric layer 21 is at least located in the main area 20, and the second piezoelectric layer 22 is at least located in the main area 20 and the edge area 30.

[0088] Among them, the orthographic projection of the surface of the first piezoelectric layer 21 facing away from the substrate 1 on the substrate 1 can coincide with the main area 20, and the orthographic projection of the surface of the first piezoelectric layer 21 close to the substrate 1 on the substrate 1 at least covers the main area 20, so that the first piezoelectric layer 21 is at least located in the main area 20.

[0089] In some embodiments, when the first piezoelectric layer 21 and the second piezoelectric layer 22 are distributed along the second direction Y, the side wall of the first piezoelectric layer 21 close to the second piezoelectric layer 22 is perpendicular to the first direction X or inclined toward the main area 20 .

[0090] The orthographic projection of the surface of the first piezoelectric layer 21 facing away from the substrate 1 on the substrate 1 coincides with the main area 20. When the side wall of the first piezoelectric layer 21 close to the second piezoelectric layer 22 is perpendicular to the first direction X, the orthographic projection of the surface of the first piezoelectric layer 21 close to the substrate 1 on the substrate 1 coincides with the main area 20, that is, the first piezoelectric layer 21 is located in the main area 20. When the side wall of the first piezoelectric layer 21 close to the second piezoelectric layer 22 is inclined toward the main area 20, the orthographic projection of the surface of the first piezoelectric layer 21 close to the substrate 1 on the substrate 1 may cover the main area 20 and at least part of the edge area 30 (that is, the first piezoelectric layer 21 is located in the main area 20 and at least part of the edge area 30), or may cover the main area 20, the edge area 30 and at least part of the gap area 40 (that is, the first piezoelectric layer 21 is located in the main area 20, the edge area 30 and at least part of the gap area 40).

[0091] In some embodiments, when the first piezoelectric layer 21 and the second piezoelectric layer 22 are distributed along the second direction Y, the side wall of the first piezoelectric layer 21 close to the second piezoelectric layer 22 includes at least one of a flat surface, a curved surface, and a folded line surface. Fig.17 As shown, the side wall of the first piezoelectric layer 21 close to the second piezoelectric layer 22 is a vertical plane.

[0092] According to the resonator provided in the embodiment of the present application, a piezoelectric structure is set up so that the piezoelectric structure includes a first piezoelectric layer located in the main area and a second piezoelectric layer located in the edge area, and the first piezoelectric layer and the second piezoelectric layer both include anisotropic dielectric materials, and the crystal orientations of the first piezoelectric layer and the second piezoelectric layer are different, so as to directionally scatter the stray mode transmitted to the edge area to the substrate, avoid the stray mode from being reflected back to the electrode finger area, thereby ensuring the main mode propagation characteristics while suppressing the stray mode and improving the performance of the resonator.

[0093] Correspondingly, an embodiment of the present application further provides a filter, including the resonator in the above embodiment, which will not be described in detail here.

[0094] According to the filter provided in the embodiment of the present application, a piezoelectric structure is set up so that the piezoelectric structure includes a first piezoelectric layer located in the main area and a second piezoelectric layer located in the edge area, and the first piezoelectric layer and the second piezoelectric layer both include anisotropic dielectric materials, and the first piezoelectric layer and the second piezoelectric layer have different crystal orientations, so as to directionally scatter the stray mode transmitted to the edge area to the substrate, avoid the stray mode from being reflected back to the electrode finger area, thereby suppressing the stray mode while ensuring the main mode propagation characteristics, improving the performance of the resonator, and further improving the performance of the filter.

[0095] Correspondingly, an embodiment of the present application further provides an electronic device, including the filter in the above embodiment, which will not be described in detail here.

[0096] According to the electronic device provided in the embodiment of the present application, a piezoelectric structure is set up so that the piezoelectric structure includes a first piezoelectric layer located in the main area and a second piezoelectric layer located in the edge area, and the first piezoelectric layer and the second piezoelectric layer both include anisotropic dielectric materials, and the first piezoelectric layer and the second piezoelectric layer have different crystal orientations, so as to directionally scatter the stray mode transmitted to the edge area to the substrate, avoid the stray mode from being reflected back to the electrode finger area, thereby ensuring the main mode propagation characteristics while suppressing the stray mode, improving the performance of the resonator, and further improving the performance of the electronic device.

[0097] The terms "first", "second", etc. in the specification and claims of this application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first", "second", etc. are generally of the same type, and the number of objects is not limited. For example, the first object can be one or more.

[0098] In the description of the present application, “plurality” means two or more.

[0099] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0100] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the claims and their equivalents.

Claims

1. A resonator, characterized in that: include: A substrate, comprising an electrode finger region, wherein the electrode finger region comprises a main body region and edge regions located on two opposite sides of the main body region along a first direction; A piezoelectric structure is located on one side of the substrate along the second direction, the piezoelectric structure includes a first piezoelectric layer at least located in the main area and a second piezoelectric layer at least located in the edge area, the first piezoelectric layer and the second piezoelectric layer both include anisotropic dielectric materials, and the first piezoelectric layer and the second piezoelectric layer have different crystal orientations; the second direction is the thickness direction of the substrate, and the second direction is perpendicular to the first direction; The electrode layer is located on a side of the piezoelectric structure facing away from the substrate.

2. The resonator according to claim 1, characterized in that The dielectric anisotropy of the first piezoelectric layer is greater than the dielectric anisotropy of the second piezoelectric layer.

3. The resonator according to claim 1, characterized in that The materials of the first piezoelectric layer and the second piezoelectric layer are the same or different, and the crystal cutting angles of the first piezoelectric layer and the second piezoelectric layer are the same or different.

4. The resonator according to claim 1, characterized in that The orthographic projection of a surface of the first piezoelectric layer facing away from the substrate on the substrate coincides with the main region.

5. The resonator according to claim 4, characterized in that The second piezoelectric layer is located on at least one of two opposite sides of the first piezoelectric layer along the first direction.

6. The resonator according to claim 5, characterized in that An interface between the first piezoelectric layer and the second piezoelectric layer is perpendicular to the first direction or inclined toward the main region.

7. The resonator according to claim 5, characterized in that The interface between the first piezoelectric layer and the second piezoelectric layer includes at least one of a plane, a curved surface, and a folded line surface.

8. The resonator according to claim 1, characterized in that The first piezoelectric layer and the second piezoelectric layer are distributed along the second direction; The second piezoelectric layer is located in the edge region and the main region.

9. The resonator according to claim 8, characterized in that The first piezoelectric layer is located between the second piezoelectric layer and the electrode layer.

10. The resonator according to claim 1, characterized in that The second piezoelectric layer is a single-layer structure or a stacked-layer structure.

11. The resonator according to any one of claims 1 to 10, characterized in that: The substrate further includes busbar regions located at opposite sides of the electrode finger region along the first direction, and a gap region located between the electrode finger region and the busbar region; The second piezoelectric layer is also located in the gap region.

12. The resonator according to claim 11, characterized in that The second piezoelectric layer is also located in the busbar region.

13. The resonator according to claim 1, characterized in that The resonator further comprises a dielectric layer; The dielectric layer is located between the substrate and the electrode layer, and is located on at least one of two opposite sides of the piezoelectric structure along the first direction.

14. A filter, characterized in that: Comprising a resonator as claimed in any one of claims 1 to 13.

15. An electronic device, characterized in that: Comprising a filter as claimed in claim 14.

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