Western shingle wave surface acoustic wave resonator, bare chip and communication assembly

Abstract

The invention relates to the field of sound wave resonance, in particular to a Sixhu wave surface acoustic wave resonator, a bare chip and a communication component, which sequentially comprise a substrate, a first piezoelectric layer, a patterned second piezoelectric layer and an interdigital electrode from bottom to top, the first piezoelectric layer and / or the second piezoelectric layer comprises at least one of a lithium tantalate layer, a lithium niobate layer, an aluminum nitride layer, a scandium-doped aluminum nitride layer, a zinc oxide layer and a piezoelectric ceramic layer; the difference between the acoustic impedance of the first piezoelectric layer and the acoustic impedance of the interdigital electrode and the difference between the acoustic impedance of the second piezoelectric layer and the acoustic impedance of the interdigital electrode are both not smaller than a preset blocking threshold value. According to the invention, the device and the bulk acoustic wave resonator can be integrated on the same bare chip, the minimum value of the difference between the acoustic impedance of the first piezoelectric layer and the acoustic impedance of the second piezoelectric layer and the acoustic impedance of the interdigital electrode is limited, and more western sha wave energy is concentrated to an effective region, so that the space occupation is reduced, the electromechanical coupling coefficient is increased, and the output power is increased.

Description

Technical Field

[0001] The invention relates to the field of acoustic wave resonance, and in particular to a Sishava wave surface acoustic wave resonator, a bare chip and a communication component. Background Art

[0002] With the continuous development of communication technology, more and more devices need to exchange information with other devices, and the miniaturization of devices has become an inevitable development goal, which also puts higher requirements on mobile communication devices.

[0003] Using multiple filter technologies in the same communication equipment will inevitably increase the size of the device. How to reduce the size of the device has become an urgent problem to be solved. In traditional structures, SAW (surface acoustic wave) filters generally use lithium niobate, lithium tantalate, or even zinc oxide as the piezoelectric layer, while BAW (bulk acoustic wave) filters generally use aluminum nitride or scandium-doped aluminum nitride as the piezoelectric layer. The difference in piezoelectric materials limits the simultaneous production of SAW and BAW filters on the same wafer. The size of SAW and BAW filters produced separately in the final use must be larger than the structure in which SAW and BAW filters are produced on the same wafer. Therefore, there is an urgent need for a higher-performance resonator that can be highly integrated with SAW or BAW filters, such as being produced on the same wafer.

[0004] Therefore, how to improve the structure of the resonator to achieve the miniaturization of the filter without hindering the miniaturization of the filter and improve the performance of the filter at the same time is an urgent problem to be solved by those skilled in the art. Summary of the invention

[0005] The object of the present invention is to provide a Sishawa surface acoustic wave resonator, a bare chip and a communication component to solve the problem in the prior art that the performance of the resonator cannot be improved without hindering the miniaturization of the resonator.

[0006] In order to solve the above technical problems, the present invention provides a Sishavar surface acoustic wave resonator, which comprises, from bottom to top, a substrate, a first piezoelectric layer, a patterned second piezoelectric layer and interdigital electrodes;

[0007] The first piezoelectric layer and / or the second piezoelectric layer comprises at least one of a lithium tantalate layer, a lithium niobate layer, an aluminum nitride layer, a scandium-doped aluminum nitride layer, a zinc oxide layer and a piezoelectric ceramic layer;

[0008] The difference between the acoustic impedance of the first piezoelectric layer and the acoustic impedance of the interdigital electrodes, and the difference between the acoustic impedance of the second piezoelectric layer and the acoustic impedance of the interdigital electrodes, are both not less than a preset blocking threshold.

[0009] Optionally, in the Sisava surface acoustic wave resonator, the blocking preset value ranges from 10 mega-Rayles to 50 mega-Rayles, including endpoint values;

[0010] And / or the first piezoelectric layer is an aluminum nitride layer, the second piezoelectric layer is a scandium-doped aluminum nitride layer, and the interdigitated electrode layer is at least one of a molybdenum electrode, an aluminum electrode, a copper electrode and a gold electrode.

[0011] Optionally, in the Sishawar surface acoustic wave resonator, a bottom electrode is also included;

[0012] The bottom electrode is disposed between the substrate and the first piezoelectric layer;

[0013] The difference between the acoustic impedance of the first piezoelectric layer and the acoustic impedance of the bottom electrode, and the difference between the acoustic impedance of the second piezoelectric layer and the acoustic impedance of the bottom electrode are both not less than a preset second threshold.

[0014] Optionally, in the Xishawa wave surface acoustic wave resonator, the interdigitated electrodes are laminated electrodes, including a plurality of electrode laminates with different acoustic impedances;

[0015] and / or,

[0016] The bottom electrode is a laminated electrode including a plurality of electrode laminates with different acoustic impedances.

[0017] Optionally, in the Sishavar surface acoustic wave resonator, the electrode stack with the smallest acoustic impedance in the interdigital electrodes is arranged in contact with the second piezoelectric layer;

[0018] and / or,

[0019] The electrode stack with the smallest acoustic impedance in the bottom electrode is arranged in contact with the first piezoelectric layer.

[0020] Optionally, in the Sishavar surface acoustic wave resonator, the interdigitated electrodes include only two electrode stacks with different acoustic impedances;

[0021] The two electrode stacks are alternately stacked in the interdigitated electrodes;

[0022] and / or,

[0023] The bottom electrode only includes two electrode stacks with different acoustic impedances;

[0024] Two types of electrode stacks are alternately stacked in the bottom electrode.

[0025] Optionally, in the Sishavar surface acoustic wave resonator, the bottom electrode and / or the interdigitated electrodes include at least one of a gold electrode, an aluminum electrode and a molybdenum electrode.

[0026] Optionally, in the Xishawa surface acoustic wave resonator, the interdigital electrodes are arranged on the surface of the second piezoelectric layer, and the width of the interdigital electrodes is smaller than the width of the second piezoelectric layer;

[0027] and / or the Xishawa surface acoustic wave resonator further comprises a non-metallic oxide layer;

[0028] The electrode where the non-metallic oxide layer is arranged in the Sishavar surface acoustic wave resonator is far away from the surface of the first piezoelectric layer.

[0029] A bare chip comprises a bulk acoustic wave resonator and any one of the above-mentioned Sishavar surface acoustic wave resonators.

[0030] A communication component comprises the bare chip.

[0031] The Xishawa wave surface acoustic wave resonator provided by the present invention comprises, from bottom to top, a substrate, a first piezoelectric layer, a patterned second piezoelectric layer and interdigital electrodes; the first piezoelectric layer and / or the second piezoelectric layer comprises at least one of a lithium tantalate layer, a lithium niobate layer, an aluminum nitride layer, a scandium-doped aluminum nitride layer, a zinc oxide layer and a piezoelectric ceramic layer; the difference between the acoustic impedance of the first piezoelectric layer and the acoustic impedance of the interdigital electrodes, and the difference between the acoustic impedance of the second piezoelectric layer and the acoustic impedance of the interdigital electrodes, are both not less than a preset blocking threshold.

[0032] The present invention excites the surface acoustic wave of the Xishawar wave through the first piezoelectric layer, the second piezoelectric layer and the interdigital electrode, and at the same time limits the materials of the two piezoelectric layers, so that the Xishawar wave surface acoustic wave resonator can be directly integrated with other bulk acoustic wave resonators on the same bare chip, and by limiting the minimum value of the difference between the acoustic impedance of the first piezoelectric layer and the second piezoelectric layer and the acoustic impedance of the interdigital electrode, the acoustic impedance gap between the electrode and the piezoelectric layer is increased, so that more Xishawar waves are reflected at the contact interface between the two, reducing the leakage of the energy of the Xishawar wave toward the substrate, and concentrating more Xishawar wave energy into the effective area of ​​the resonator, thereby greatly reducing the space occupation of the composite resonator composed of the surface acoustic wave resonator and the bulk acoustic wave resonator, while improving the electromechanical coupling coefficient of the resonator and increasing the output power of the resonator. The present invention also provides a bare chip and a communication component with the above beneficial effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present invention or the technical solutions of the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0034] FIG1 is a schematic structural diagram of a specific embodiment of a Sisawa wave surface acoustic wave resonator provided by the present invention;

[0035] FIG2 is a schematic structural diagram of a specific embodiment of a Sisawa wave surface acoustic wave resonator provided by the present invention;

[0036] FIG3 is a schematic structural diagram of a specific embodiment of a Sisawa wave surface acoustic wave resonator provided by the present invention;

[0037] FIG4 is a schematic structural diagram of a specific embodiment of a Sisawa wave surface acoustic wave resonator provided by the present invention;

[0038] FIG5 is a schematic structural diagram of a specific implementation of the Sisawa wave surface acoustic wave resonator provided by the present invention.

[0039] In the figure, it includes 10-substrate, 21-first piezoelectric layer, 22-second piezoelectric layer, 30-interdigitated electrodes, 40-bottom electrode, 50-non-metallic oxide layer, 01-first electrode stack, and 02-second electrode stack. DETAILED DESCRIPTION

[0040] In order to enable those skilled in the art to better understand the scheme of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0041] The core of the present invention is to provide a Sishavar surface acoustic wave resonator, a structural schematic diagram of a specific embodiment of which is shown in FIG1 , referred to as specific embodiment 1, which includes, from bottom to top, a substrate 10, a first piezoelectric layer 21, a patterned second piezoelectric layer 22 and interdigital electrodes 30;

[0042] The first piezoelectric layer 21 and / or the second piezoelectric layer 22 includes at least one of a lithium tantalate layer, a lithium niobate layer, an aluminum nitride layer, a scandium-doped aluminum nitride layer, a zinc oxide layer and a piezoelectric ceramic layer;

[0043] The difference between the acoustic impedance of the first piezoelectric layer 21 and the acoustic impedance of the interdigital electrode 30 , and the difference between the acoustic impedance of the second piezoelectric layer 22 and the acoustic impedance of the interdigital electrode 30 , are both not less than a preset blocking threshold.

[0044] Among them, the blocking preset value ranges from 10 mega-Rayles to 50 mega-Rayles, including endpoint values, such as any one of 10.0 mega-Rayles, 23.2 mega-Rayles or 50.0 mega-Rayles. The difference between the acoustic impedance of the first piezoelectric layer 21 and the second piezoelectric layer 22 and the acoustic impedance of the interdigital electrode 30 is not less than the blocking preset value, so that the Xishawar wave can be reflected at the contact interface between the electrode and the piezoelectric layer to avoid Xishawar wave leakage. Within the above-mentioned acoustic impedance range, the properties of the material will not reflect overly differentiated physical properties due to the excessive difference in acoustic impedance, which will increase the difficulty of production, nor will it fail to achieve a good Xishawar wave blocking effect due to the excessively small difference in acoustic impedance.

[0045] In a specific embodiment, the first piezoelectric layer 21 is an aluminum nitride layer, the second piezoelectric layer 22 is a scandium-doped aluminum nitride layer, and the interdigital electrode 30 layer is at least one of a molybdenum electrode, an aluminum electrode, a copper electrode, and a gold electrode. The composite piezoelectric layer composed of an aluminum nitride layer and a scandium-doped aluminum nitride layer has a better electromechanical coupling coefficient. On this basis, electrode types with a large difference in acoustic impedance from the aluminum nitride layer and the scandium-doped aluminum nitride layer are further provided, wherein the acoustic impedance of the molybdenum electrode and the gold electrode is much greater than that of the aluminum nitride layer and the scandium-doped aluminum nitride layer, and the acoustic impedance of the aluminum electrode is much smaller than that of the aluminum nitride layer and the scandium-doped aluminum nitride layer. Of course, other material combinations can also be selected according to actual conditions, and the present invention is not limited here.

[0046] Furthermore, the Xishawa surface acoustic wave resonator further includes a bottom electrode 40;

[0047] The bottom electrode 40 is disposed between the substrate 10 and the first piezoelectric layer 21;

[0048] The difference between the acoustic impedance of the first piezoelectric layer 21 and the acoustic impedance of the bottom electrode 40 , and the difference between the acoustic impedance of the second piezoelectric layer 22 and the acoustic impedance of the bottom electrode 40 , are both not less than a preset second threshold.

[0049] Please refer to Figure 2. The top and bottom surfaces of the Xishawa wave surface acoustic wave resonator in Figure 2 are both provided with electrodes. The provision of the bottom electrode 40 can significantly improve the electromechanical coupling coefficient of the resonator and improve the device performance. The material of the bottom electrode 40 can refer to the interdigital electrode 30 mentioned above, and the present invention will not be repeated here. Of course, depending on the selected material, the second threshold value can be the same as the blocking threshold value mentioned above, or it can be different, and can be adjusted according to actual conditions, and the present invention is not limited here.

[0050] The bottom electrode 40 and the interdigitated electrode 30 may be single-layer electrodes, such as a molybdenum electrode, an aluminum electrode or a gold electrode, wherein the molybdenum electrode, the aluminum electrode and the gold electrode may be single-element metal electrodes or corresponding alloy electrodes; of course, the bottom electrode 40 and the interdigitated electrode 30 may also be multilayer electrodes composed of multiple layers, and different multilayer materials may be different, and may be selected according to actual conditions.

[0051] In addition, the Xishawa wave surface acoustic wave resonator further includes a non-metallic oxide layer 50;

[0052] The electrode where the non-metallic oxide layer 50 is disposed in the Sisava surface acoustic wave resonator is far away from the surface of the first piezoelectric layer 21 .

[0053] The electrodes in the Xishawa wave surface acoustic wave resonator include the interdigital electrodes 30 and the bottom electrode 40 mentioned above, that is, the non-metallic oxide layer 50 can be arranged alone on the outside of the interdigital electrodes 30 or the outside of the bottom electrode 40 (that is, on the side away from the first piezoelectric layer 21), or can be arranged on the outside of the interdigital electrodes 30 and the bottom electrode 40 at the same time. Please refer to Figure 3, which is a structural schematic diagram after the non-metallic oxide layer 50 is arranged on the outside of the bottom electrode 40. After adding the non-metallic oxide layer 50, the acoustic wave leakage can be further reduced, and the temperature drift of the device can be reduced, and the temperature stability of the device can be improved. The non-metallic oxide layer 50 is preferably a silicon dioxide layer. Of course, other non-metallic oxide layers can also be selected, and the present invention will not be repeated here.

[0054] As a specific implementation, the interdigital electrodes 30 are disposed on the surface of the second piezoelectric layer 22 , and the width of the interdigital electrodes 30 is smaller than the width of the second piezoelectric layer 22 .

[0055] The width of the interdigitated electrode 30 is different from the width of the second piezoelectric layer 22, so that the width of the interdigitated electrode 30 is smaller than the width of the second piezoelectric layer 22 to increase the resonant frequency of the resonator, and can be further configured to reduce the influence of the parasitic resonance of the resonator on the Xishawa wave resonance.

[0056] The Xishawa wave surface acoustic wave resonator provided by the present invention includes, from bottom to top, a substrate 10, a first piezoelectric layer 21, a patterned second piezoelectric layer 22 and an interdigitated electrode 30; the first piezoelectric layer 21 and / or the second piezoelectric layer 22 include at least one of a lithium tantalate layer, a lithium niobate layer, an aluminum nitride layer, a scandium-doped aluminum nitride layer, a zinc oxide layer and a piezoelectric ceramic layer; the difference between the acoustic impedance of the first piezoelectric layer 21 and the acoustic impedance of the interdigitated electrode 30, and the difference between the acoustic impedance of the second piezoelectric layer 22 and the acoustic impedance of the interdigitated electrode 30, are not less than a preset blocking threshold. The present invention excites the surface acoustic wave of the Xishawar wave through the first piezoelectric layer 21, the second piezoelectric layer 22 and the interdigital electrode 30, and at the same time limits the materials of the two piezoelectric layers, so that the Xishawar wave surface acoustic wave resonator can be directly integrated with other bulk acoustic wave resonators on the same bare chip, and by limiting the minimum value of the difference between the acoustic impedance of the first piezoelectric layer 21 and the second piezoelectric layer 22 and the acoustic impedance of the interdigital electrode 30, the acoustic impedance difference between the electrodes and the piezoelectric layers is increased, so that more Xishawar waves are reflected at the contact interface between the two, the energy leakage of the Xishawar wave toward the substrate 10 is reduced, and more Xishawar wave energy is concentrated in the effective area of ​​the resonator, thereby greatly reducing the space occupation of the composite resonator composed of the surface acoustic wave resonator and the bulk acoustic wave resonator, while improving the electromechanical coupling coefficient of the resonator and increasing the output power of the resonator.

[0057] On the basis of the first embodiment, the present invention further improves the electrodes in the Sishavar surface acoustic wave resonator to obtain a second embodiment, the corresponding structural diagram of which is shown in FIG4 , which includes, from bottom to top, a substrate 10, a first piezoelectric layer 21, a patterned second piezoelectric layer 22 and interdigital electrodes 30;

[0058] The first piezoelectric layer 21 and / or the second piezoelectric layer 22 includes at least one of a lithium tantalate layer, a lithium niobate layer, an aluminum nitride layer, a scandium-doped aluminum nitride layer, a zinc oxide layer and a piezoelectric ceramic layer;

[0059] The difference between the acoustic impedance of the first piezoelectric layer 21 and the acoustic impedance of the interdigital electrode 30, and the difference between the acoustic impedance of the second piezoelectric layer 22 and the acoustic impedance of the interdigital electrode 30, are not less than a preset blocking threshold;

[0060] The interdigitated electrode 30 is a laminated electrode, comprising a plurality of electrode laminates with different acoustic impedances;

[0061] and / or,

[0062] The bottom electrode 40 is a laminated electrode including a plurality of electrode laminates with different acoustic impedances.

[0063] The difference between this specific embodiment and the above specific embodiment is that in this specific embodiment, at least one of the interdigitated electrodes 30 and the bottom electrode 40 in the Xishawa wave surface acoustic wave resonator is set as a multi-layer stacked electrode, and the remaining structures are the same as the above specific embodiments and will not be elaborated here.

[0064] In the present preferred embodiment, it is further defined that at least one of the interdigitated electrodes 30 and the bottom electrode 40 is a stacked electrode, that is, the interdigitated electrodes 30 and / or the bottom electrode 40 include a plurality of stacks, for example, may include a first electrode stack 01 and a second electrode stack 02, two electrode stacks with different acoustic impedances. By arranging electrode stacks with different acoustic impedances to be stacked on each other, the leakage of Xishawa waves can be further reduced and the blocking effect of the resonator can be improved.

[0065] Furthermore, the electrode stack with the smallest acoustic impedance in the interdigital electrodes 30 is arranged in contact with the second piezoelectric layer 22;

[0066] and / or,

[0067] The electrode stack with the smallest acoustic impedance in the bottom electrode 40 is arranged in contact with the first piezoelectric layer 21 .

[0068] In other words, the stack with the smallest acoustic impedance in the electrode is directly attached to the corresponding piezoelectric layer (that is, the piezoelectric layer closest to contact, which is the second piezoelectric layer 22 for the interdigitated electrode 30 and the first piezoelectric layer 21 for the bottom electrode). Continuing with the previous example, the interdigitated electrode 30 and the bottom electrode 40 both include two electrode stacks with different acoustic impedances, a first electrode stack 01 and a second electrode stack 02, wherein the acoustic impedance of the first electrode stack 01 is smaller than the acoustic impedance of the second electrode stack 02. Please refer to FIG. 4 . The interdigitated electrode 30 and the bottom electrode 40 in FIG. 4 both include the first electrode stack 01 and the second electrode stack 02, and since the interdigitated electrode 30 is arranged above the second piezoelectric layer 22, the first electrode stack 01 of the interdigitated electrode 30 is arranged at the bottom of the interdigitated electrode 30, and the bottom electrode 40 is arranged below the first piezoelectric layer 21, therefore, the first electrode stack 01 of the bottom electrode 40 is arranged at the top of the bottom electrode 40. By attaching the electrode stack with the smallest acoustic impedance to the corresponding piezoelectric layer, the high-order resonance can be further away from the main resonance area. In other words, the frequency range of the parasitic resonance can be further away from the resonance frequency of the Xishawa wave, further improving the performance of the resonator.

[0069] Furthermore, the interdigitated electrodes only include two electrode stacks with different acoustic impedances;

[0070] The two electrode stacks are alternately stacked in the interdigitated electrodes;

[0071] and / or,

[0072] The bottom electrode only includes two electrode stacks with different acoustic impedances;

[0073] Two types of electrode stacks are alternately stacked in the bottom electrode.

[0074] In this preferred embodiment, the interdigitated electrodes 30 and / or the bottom electrode 40 include at least three electrode stacks to achieve the alternate arrangement of two electrode stacks with different acoustic impedances. Alternating the two electrode stacks with different acoustic impedances can further prevent the leakage of the Xishawa wave, as shown in Figure 5. Continuing with the previous example, the two electrode stacks with different acoustic impedances are called the first electrode stack 01 and the second electrode stack 02. Preferably, the thickness ratio of the first electrode stack 01 to the second electrode stack 02 is in the range of 50:1 to 1:50.

[0075] In addition, the thickness of the interdigitated electrode 30 and / or the bottom electrode 40 ranges from 20 nanometers to 800 nanometers, including endpoint values, such as any one of 20.0 nanometers, 511.1 nanometers or 800.0 nanometers. When the electrode thickness is thinner (less than 20 nanometers), the resistance of the electrode increases, the electrical loss increases, and the Q value (quality factor) of the device decreases; when the electrode thickness is thicker (greater than 800 nanometers), the acoustic wave vibration phenomenon decreases and the Q value decreases.

[0076] The present invention also provides a bare chip, which includes a bulk acoustic wave resonator and a Xishawa surface acoustic wave resonator as described in any one of the above. The Xishawa surface acoustic wave resonator provided by the present invention includes, from bottom to top, a substrate 10, a first piezoelectric layer 21, a patterned second piezoelectric layer 22 and an interdigital electrode 30; the first piezoelectric layer 21 and / or the second piezoelectric layer 22 include at least one of a lithium tantalate layer, a lithium niobate layer, an aluminum nitride layer, a scandium-doped aluminum nitride layer, a zinc oxide layer and a piezoelectric ceramic layer; the difference between the acoustic impedance of the first piezoelectric layer 21 and the acoustic impedance of the interdigital electrode 30, and the difference between the acoustic impedance of the second piezoelectric layer 22 and the acoustic impedance of the interdigital electrode 30, are not less than a preset blocking threshold. The present invention excites the surface acoustic wave of the Xishawar wave through the first piezoelectric layer 21, the second piezoelectric layer 22 and the interdigital electrode 30, and at the same time limits the materials of the two piezoelectric layers, so that the Xishawar wave surface acoustic wave resonator can be directly integrated with other bulk acoustic wave resonators on the same bare chip, and by limiting the minimum value of the difference between the acoustic impedance of the first piezoelectric layer 21 and the second piezoelectric layer 22 and the acoustic impedance of the interdigital electrode 30, the acoustic impedance difference between the electrodes and the piezoelectric layers is increased, so that more Xishawar waves are reflected at the contact interface between the two, the energy leakage of the Xishawar wave toward the substrate 10 is reduced, and more Xishawar wave energy is concentrated in the effective area of ​​the resonator, thereby greatly reducing the space occupation of the composite resonator composed of the surface acoustic wave resonator and the bulk acoustic wave resonator, while improving the electromechanical coupling coefficient of the resonator and increasing the output power of the resonator.

[0077] The present invention also provides a communication component, which includes a bare chip as described in any one of the above. The Xishawa wave surface acoustic wave resonator provided by the present invention includes, from bottom to top, a substrate 10, a first piezoelectric layer 21, a patterned second piezoelectric layer 22 and an interdigital electrode 30; the first piezoelectric layer 21 and / or the second piezoelectric layer 22 include at least one of a lithium tantalate layer, a lithium niobate layer, an aluminum nitride layer, a scandium-doped aluminum nitride layer, a zinc oxide layer and a piezoelectric ceramic layer; the difference between the acoustic impedance of the first piezoelectric layer 21 and the acoustic impedance of the interdigital electrode 30, and the difference between the acoustic impedance of the second piezoelectric layer 22 and the acoustic impedance of the interdigital electrode 30, are not less than a preset blocking threshold. The present invention excites the surface acoustic wave of the Xishawar wave through the first piezoelectric layer 21, the second piezoelectric layer 22 and the interdigital electrode 30, and at the same time limits the materials of the two piezoelectric layers, so that the Xishawar wave surface acoustic wave resonator can be directly integrated with other bulk acoustic wave resonators on the same bare chip, and by limiting the minimum value of the difference between the acoustic impedance of the first piezoelectric layer 21 and the second piezoelectric layer 22 and the acoustic impedance of the interdigital electrode 30, the acoustic impedance difference between the electrodes and the piezoelectric layers is increased, so that more Xishawar waves are reflected at the contact interface between the two, the energy leakage of the Xishawar wave toward the substrate 10 is reduced, and more Xishawar wave energy is concentrated in the effective area of ​​the resonator, thereby greatly reducing the space occupation of the composite resonator composed of the surface acoustic wave resonator and the bulk acoustic wave resonator, while improving the electromechanical coupling coefficient of the resonator and increasing the output power of the resonator.

[0078] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0079] It should be noted that, in this specification, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device including the element.

[0080] The above is a detailed introduction to the Sisawa wave surface acoustic wave resonator, bare chip and communication component provided by the present invention. Specific examples are used in this article to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the present invention, the present invention can also be improved and modified, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A Sisava surface acoustic wave resonator, characterized in that: From bottom to top, it includes a substrate, a first piezoelectric layer, a patterned second piezoelectric layer and interdigital electrodes; The first piezoelectric layer and / or the second piezoelectric layer comprises at least one of a lithium tantalate layer, a lithium niobate layer, an aluminum nitride layer, a scandium-doped aluminum nitride layer, a zinc oxide layer and a piezoelectric ceramic layer; The difference between the acoustic impedance of the first piezoelectric layer and the acoustic impedance of the interdigital electrodes, and the difference between the acoustic impedance of the second piezoelectric layer and the acoustic impedance of the interdigital electrodes, are both not less than a preset blocking threshold.

2. The Sisawa surface acoustic wave resonator according to claim 1, characterized in that: The blocking preset value ranges from 10 million Rayles to 50 million Rayles, including the endpoint values; And / or the first piezoelectric layer is an aluminum nitride layer, the second piezoelectric layer is a scandium-doped aluminum nitride layer, and the interdigitated electrode layer is at least one of a molybdenum electrode, an aluminum electrode, a copper electrode and a gold electrode.

3. The Sisawa surface acoustic wave resonator according to claim 1, characterized in that: Also included is a bottom electrode; The bottom electrode is disposed between the substrate and the first piezoelectric layer; The difference between the acoustic impedance of the first piezoelectric layer and the acoustic impedance of the bottom electrode, and the difference between the acoustic impedance of the second piezoelectric layer and the acoustic impedance of the bottom electrode are both not less than a preset second threshold.

4. The Sisawa surface acoustic wave resonator according to claim 3, characterized in that: The interdigitated electrodes are laminated electrodes, comprising a plurality of electrode laminates with different acoustic impedances; and / or, The bottom electrode is a laminated electrode including a plurality of electrode laminates with different acoustic impedances.

5. The Sisawa surface acoustic wave resonator according to claim 4, characterized in that: The electrode stack with the smallest acoustic impedance in the interdigital electrodes is arranged in contact with the second piezoelectric layer; and / or, The electrode stack with the smallest acoustic impedance in the bottom electrode is arranged in contact with the first piezoelectric layer.

6. The Sisawa surface acoustic wave resonator according to claim 5, characterized in that: The interdigitated electrodes only include two electrode stacks with different acoustic impedances; The two electrode stacks are alternately stacked in the interdigitated electrodes; and / or, The bottom electrode only includes two electrode stacks with different acoustic impedances; Two types of electrode stacks are alternately stacked in the bottom electrode.

7. The Sisawa surface acoustic wave resonator according to claim 3, characterized in that: The bottom electrode and / or the interdigitated electrodes include at least one of a gold electrode, an aluminum electrode and a molybdenum electrode.

8. The Sisawa surface acoustic wave resonator according to any one of claims 1 to 7, characterized in that: The interdigital electrodes are arranged on the surface of the second piezoelectric layer, and the width of the interdigital electrodes is smaller than the width of the second piezoelectric layer; and / or the Xishawa surface acoustic wave resonator further comprises a non-metallic oxide layer; The electrode where the non-metallic oxide layer is arranged in the Sishavar surface acoustic wave resonator is far away from the surface of the first piezoelectric layer.

9. A bare chip, characterized in that: The bare chip includes a bulk acoustic wave resonator and a Sisava surface acoustic wave resonator according to any one of claims 1 to 8.

10. A communication component, characterized in that: The communication component includes the bare chip as claimed in claim 9.

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