Resonators and electronic devices

Abstract

The present application relates to a resonator and electronic device. A new type of resonator is formed by stacking a high and low acoustic impedance alternating layer, a bottom frequency temperature coefficient compensation layer, a bottom electrode layer, a piezoelectric layer, a top electrode layer and a top frequency temperature coefficient compensation layer on a substrate in sequence through a special microfabrication process flow. Due to this special stacking geometry, the resonator can simultaneously exhibit good characteristics of low loss, wide band, low temperature sensitivity and small size, and has excellent operation reliability.

Description

[Technical field]

[0001] This application relates to the field of semiconductor technology, and in particular to resonators and electronic devices. [Background technology]

[0002] In high-end radio frequency front-end modules, acoustic devices are used to synthesize devices with filtering functions of low loss and fast roll-off characteristics. Such devices are microfabricated structures manufactured based on semiconductor technology, and utilize acoustic vibrations to synthesize resonator functions equivalent to cascaded inductors and capacitors. These devices, usually called surface acoustic wave (SAW) devices or bulk acoustic wave (BAW) devices, have become the mainstream solution for radio frequency filtering in high-end front-end modules because they are compatible with modern electronic devices and can obtain very high quality factors Q (directly related to low loss) with very small overall dimensions. Especially at high frequencies above 2.5 GHz and low loss, the performance of BAW devices is superior to SAW devices, so BAW devices are more widely applied in high-frequency filtering technology in high-end front-end modules.

[0003] Traditional BAW devices sandwich a piezoelectric film layer between metal electrodes and other film layers to reduce the temperature sensitivity of the device. There are two main types of BAW device structures: one is based on a floating film, and the other is based on a film fixed to a substrate with a reflective stack. In these two cases, the resonant frequency of the acoustic device is set by the total thickness of the piezoelectric layer and the other film in contact with it. The new 5G standard requires operation at higher frequencies (above 3 GHz) and larger bandwidths. This brings new challenges to BAW devices, where they must either utilize very thin membrane layers or sacrifice bandwidth to meet the high frequency requirements. In traditional BAW devices, there is an inevitable trade-off between the two performances, which leads to limited yields, high costs, or a great challenge for the manufacturing and integration of passive components in the acoustic package. These passive components are usually used to compensate for the limited nature of acoustic equipment, but in the 5G standard, their performance is extended and causes additional losses, so they are not sufficient to reach this goal. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] China Patent Application Publication No. 109921759 Summary of the Invention [Problem to be solved by the invention]

[0005] In view of this, there is a need to provide a resonator and electronic device that addresses the above problems. [Means for solving the problem]

[0006] The resonator includes a high and low acoustic impedance alternating layer provided on a substrate, a bottom frequency temperature coefficient compensation layer provided on a first surface of the high and low acoustic impedance alternating layer, the contact surface of the high and low acoustic impedance alternating layer with the substrate being a second surface of the high and low acoustic impedance alternating layer, and the first surface of the high and low acoustic impedance alternating layer and the second surface of the high and low acoustic impedance alternating layer being disposed opposite each other, and a bottom electrode layer provided on the first surface of the bottom frequency temperature coefficient compensation layer, the contact surface of the bottom frequency temperature coefficient compensation layer with the high and low acoustic impedance alternating layer being a second surface of the bottom frequency temperature coefficient compensation layer, and the first surface of the bottom frequency temperature coefficient compensation layer and the second surface of the bottom frequency temperature coefficient compensation layer being disposed opposite each other. the piezoelectric layer is provided on a first surface of the bottom electrode layer, the contact surface of the bottom electrode layer with the bottom frequency temperature coefficient compensation layer being the second surface of the bottom electrode layer, and the first surface of the bottom electrode layer and the second surface of the bottom electrode layer being disposed opposite each other; a top electrode layer is provided on the first surface of the piezoelectric layer, the contact surface of the piezoelectric layer with the bottom electrode layer being the second surface of the piezoelectric layer, and the first surface of the piezoelectric layer and the second surface of the piezoelectric layer being disposed opposite each other; and a top frequency temperature coefficient compensation layer is provided on the first surface of the top electrode layer, the contact surface of the top electrode layer with the piezoelectric layer being the second surface of the top electrode layer, and the first surface of the top electrode layer and the second surface of the top electrode layer being disposed opposite each other.

[0007] In one embodiment, the high and low acoustic impedance alternating layer includes a high acoustic impedance layer and a low acoustic impedance layer, the acoustic impedance of the high acoustic impedance layer is higher than the acoustic impedance of the low acoustic impedance layer, the high acoustic impedance layer and the low acoustic impedance layer are arranged in an alternating stack, the contact layer with the substrate in the high and low acoustic impedance alternating layer is a low acoustic impedance layer, and the contact layer with the bottom frequency temperature coefficient compensation layer in the high and low acoustic impedance alternating layer is a high acoustic impedance layer.

[0008] In one embodiment, the high acoustic impedance layer is not exactly equal in thickness to the low acoustic impedance layer.

[0009] In one embodiment, the high acoustic impedance layer has the same thickness as the low acoustic impedance layer.

[0010] In one embodiment, the resonator further includes a medium layer provided on a first surface of the top frequency temperature coefficient compensation layer, a contact surface of the top frequency temperature coefficient compensation layer with the top electrode layer is a second surface of the top frequency temperature coefficient compensation layer, and the first surface of the top frequency temperature coefficient compensation layer and the second surface of the top frequency temperature coefficient compensation layer are arranged opposite to each other.

[0011] In one embodiment, the resonator further includes a metal layer provided on a first surface of the top electrode layer, the top frequency temperature coefficient compensation layer is provided on the first surface of the metal layer, a contact surface of the metal layer with the top electrode layer is a second surface of the metal layer, and the first surface of the metal layer and the second surface of the metal layer are arranged opposite to each other.

[0012] In one embodiment, the projections of the bottom electrode layer and the top electrode layer in a direction perpendicular to the substrate are both polygonal.

[0013] In one embodiment, the high and low acoustic impedance alternating layer, the bottom frequency temperature coefficient compensation layer, the bottom electrode layer, the piezoelectric layer, the top electrode layer and the top frequency temperature coefficient compensation layer all have the same length in the same direction parallel to the substrate.

[0014] In one embodiment, the alternating high and low acoustic impedance layer, the bottom frequency temperature coefficient compensation layer, the bottom electrode layer, the piezoelectric layer, the top electrode layer and the top frequency temperature coefficient compensation layer do not have exactly the same length in the same direction parallel to the substrate.

[0015] The electronic device includes the resonator described above. Effect of the Invention

[0016] According to the above resonator and electronic device, a high and low acoustic impedance alternating layer, a bottom frequency temperature coefficient compensation layer, a bottom electrode layer, a piezoelectric layer, a top electrode layer and a top frequency temperature coefficient compensation layer are sequentially stacked on a substrate through a special microfabrication process flow to form a new type of resonator, which has a special stacking geometric structure and can simultaneously exhibit good characteristics of low loss, wide band, low temperature sensitivity and small size, and has excellent operation reliability. [Brief description of the drawings]

[0017] In order to more clearly explain the technical solutions in the embodiments of the present application or the prior art, the following briefly introduces drawings necessary for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some of the embodiments of the present application, and those skilled in the art can obtain other drawings based on these drawings without requiring any creative efforts. [Figure 1] FIG. 2 is a schematic cross-sectional view of a resonator according to an embodiment. [Diagram 2] FIG. 2 is a schematic plan view of a resonator according to an embodiment. [Diagram 3] FIG. 13 is a schematic cross-sectional view of a resonator according to another embodiment. [Figure 4] FIG. 13 is a schematic cross-sectional view of a resonator according to another embodiment. [Diagram 5] FIG. 13 is a schematic cross-sectional view of a resonator according to still another embodiment. [Figure 6] 1A and 1B are schematic diagrams for comparing resonators with different resonant frequencies in one embodiment. [Figure 7] FIG. 13 is a schematic cross-sectional view of a resonator according to another embodiment. [Figure 8] 1A and 1B are schematic diagrams for comparing resonators with different resonant frequencies in one embodiment. [Figure 9] FIG. 2 is a schematic diagram showing the configuration of a resonator having square electrodes in one embodiment. [Figure 10] FIG. 2 is a schematic diagram showing the configuration of a resonator having hexagonal electrodes in one embodiment. [Figure 11]FIG. 13 is a schematic cross-sectional view of a resonator according to another embodiment. [Figure 12] FIG. 13 is a schematic cross-sectional view of a resonator according to still another embodiment. [Figure 13] FIG. 2 is a schematic diagram of frequency response of admittance of a resonator in one embodiment. [Figure 14] FIG. 13 is a schematic diagram of frequency response of admittance of a resonator in another embodiment. [Figure 15] FIG. 4 is a schematic diagram of stress distribution in a resonator according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] In order to facilitate understanding of the present application, a more complete description of the present application will be provided below with reference to the accompanying drawings, in which preferred embodiments of the present application are shown. However, the present application can be realized in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to provide a more thorough and complete understanding of the disclosure of the present application.

[0019] 1, the resonator includes a high and low acoustic impedance alternating layer 10 provided on a substrate, a bottom frequency temperature coefficient compensation layer 20 provided on a first surface of the high and low acoustic impedance alternating layer 10, the contact surface of the high and low acoustic impedance alternating layer 10 with the substrate being the second surface of the high and low acoustic impedance alternating layer 10, and the bottom frequency temperature coefficient compensation layer 20 is disposed so that the first surface of the high and low acoustic impedance alternating layer 10 and the second surface of the high and low acoustic impedance alternating layer 10 face each other, and a bottom electrode layer 30 provided on the first surface of the bottom frequency temperature coefficient compensation layer 20, the contact surface of the bottom frequency temperature coefficient compensation layer 20 with the high and low acoustic impedance alternating layer 10 being the second surface of the bottom frequency temperature coefficient compensation layer 20, and the first surface of the bottom frequency temperature coefficient compensation layer 20 and the second surface of the bottom frequency temperature coefficient compensation layer 20 face each other. the piezoelectric layer 40 is provided on a first surface of the bottom electrode layer 30, the contact surface of the bottom electrode layer 30 with the bottom frequency temperature coefficient compensation layer 20 being the second surface of the bottom electrode layer 30, and the first surface of the bottom electrode layer 30 and the second surface of the bottom electrode layer 30 being disposed opposite each other; a top electrode layer 50 is provided on the first surface of the piezoelectric layer 40, the contact surface of the piezoelectric layer 40 with the bottom electrode layer 30 being the second surface of the piezoelectric layer 40, and the first surface of the piezoelectric layer 40 and the second surface of the piezoelectric layer 40 being disposed opposite each other; and a top frequency temperature coefficient compensation layer 60 is provided on the first surface of the top electrode layer 50, the contact surface of the top electrode layer 50 with the piezoelectric layer 40 being the second surface of the top electrode layer 50, and the first surface of the top electrode layer 50 and the second surface of the top electrode layer 50 being disposed opposite each other.

[0020] Specifically, the plan view of the resonator of this embodiment is as shown in FIG. 2, and the laminated structure shown in FIG. 1 is a schematic cross-sectional view of the resonator shown in FIG. 2 taken along line A-A'. In the structure shown in FIG. 2, metal connection lines, i.e., electrode lead lines, are drawn out from the bottom electrode layer 30 and the top electrode layer 50, and windows are opened in the passivation layer above the electrode lead lines to expose the electrode lead lines for electrical connection. The high and low acoustic impedance alternating layer 10 is a layered structure formed by alternately laminating high acoustic impedance layers and low acoustic impedance layers, and the selection of the high acoustic impedance layer and the low acoustic impedance layer is not unique, and it is sufficient to ensure that the acoustic impedance of the high acoustic impedance layer is higher than that of the low acoustic impedance layer. The resonator of this embodiment is divided into two parts, a top stack and a bottom stack, the top stack part is composed of two electrode layers (i.e., bottom electrode layer 30 and top electrode layer 50), two frequency temperature coefficient compensation layers (i.e., bottom frequency temperature coefficient compensation layer 20 and top frequency temperature coefficient compensation layer 60), and a piezoelectric layer 40 sandwiched between the top electrode layer 50 and the bottom electrode layer 30, the bottom stack part is mainly composed of high and low acoustic impedance alternating layer 10, the top stack part is disposed on the top of the bottom stack part, and the bottom stack part is disposed on the substrate. Thus, the stack structure of the resonator provided in this embodiment is stacked on the top of the substrate as a whole.

[0021] However, this substrate may be a wafer substrate made of any material.In one detailed embodiment, in order to show high acoustic impedance, specifically, silicon, silicon carbide, sapphire, lithium niobate, lithium tantalate, glass, quartz, aluminum nitride and diamond can be used to obtain the wafer substrate, or a combination of silicon, silicon carbide, sapphire, lithium niobate, lithium tantalate, glass, quartz, aluminum nitride and diamond can be used to obtain the wafer substrate.

[0022] The phase length is the phase shift that occurs when an acoustic wave propagates through a medium having a certain thickness, and its magnitude is the ratio of the absolute thickness of the medium to the phase velocity of the acoustic wave, so the magnitude of the phase length can also intuitively indicate the thickness of the medium. In one embodiment, the total phase length of the top stack portion should be larger than a half period, i.e., t_p should be larger than π, thus ensuring that the device can operate at harmonics of the most fundamental vibration mode. For example, in one embodiment, taking the third mode as an example, the total thickness of the top stack portion can be 2π, i.e., t_p=2π, for the third mode.

[0023] The types of the bottom frequency temperature coefficient compensation layer 20 and the top frequency temperature coefficient compensation layer 60 are not unique. In one embodiment, the bottom frequency temperature coefficient compensation layer 20 and the top frequency temperature coefficient compensation layer 60 may be a film layer formed of any one of silicon dioxide, silicon monoxide, tellurium oxide, and spin glass, or may be a film layer formed by adding a doping agent / impurity to silicon dioxide, silicon monoxide, tellurium oxide, and spin glass. In other embodiments, film layers of other material types may be adopted as long as they have an inverse temperature coefficient to that of the piezoelectric layer 40.

[0024] Similarly, the specific types of the bottom electrode layer 30, the top electrode layer 50 and the piezoelectric layer 40 provided in this embodiment are not unique. In different embodiments, different types of material layers can be adopted as the bottom electrode layer 30, the top electrode layer 50 or the piezoelectric layer 40 according to different needs. For example, in one embodiment, the bottom electrode layer 30 and the top electrode layer 50 can be any one of Al (aluminum), Ru (ruthenium), Mo (molybdenum), W (tungsten), Ti (titanium), Ta (tantalum), Pt (platinum) and Au (gold), or can be an alloy material formed of Al, Ru, Mo, W, Ti, Ta, Pt, Au, etc. The piezoelectric layer 40 can be aluminum nitride. (AIN) , lithium niobate (LiNbO 3) , lithium tantalate (LiTaO 3 ) ,quartz (Quartz) , zinc oxide (ZnO) , lead zirconate titanate (PZT) Any one of the above may be adopted.

[0025] Referring to FIG. 3 , in one embodiment, the high and low acoustic impedance alternating layer 10 includes a high acoustic impedance layer 12 and a low acoustic impedance layer 11, the acoustic impedance of the high acoustic impedance layer 12 is higher than the acoustic impedance of the low acoustic impedance layer 11, the high acoustic impedance layer 12 and the low acoustic impedance layer 11 are arranged in an alternating stack, the contact layer with the substrate in the high and low acoustic impedance alternating layer 10 is the low acoustic impedance layer 11, and the contact layer with the bottom frequency temperature coefficient compensation layer 20 in the high and low acoustic impedance alternating layer 10 is the high acoustic impedance layer 12.

[0026] Specifically, the number of layers specifically included in the high and low acoustic impedance alternating layer 10 is not unique. In one simple embodiment, the high and low acoustic impedance alternating layer 10 is provided with only one high acoustic impedance layer 12 and one low acoustic impedance layer 11, and the high acoustic impedance layer 12 is located on top of the low acoustic impedance layer 11. In other embodiments, more high acoustic impedance layers 12 and low acoustic impedance layers 11 can be installed according to the actual usage scene and the user's demand, as long as it can be ensured that the high acoustic impedance layers 12 and the low acoustic impedance layers 11 are installed alternately in sequence, and the contact layer with the bottom frequency temperature coefficient compensation layer 20 is the high acoustic impedance layer 12, and the contact layer with the substrate is the low acoustic impedance layer 11.

[0027] In one embodiment, high acoustic impedance layer 12 is not exactly equal in thickness to low acoustic impedance layer 11 .

[0028] Specifically, in this embodiment, when the number of the high acoustic impedance layers 12 and the low acoustic impedance layers 11 are both plural, in order to ensure proper reflection of the longitudinal and shear vibrations generated by the piezoelectric layer 40, High and low acoustic impedance alternating layers 10 It is necessary to optimize the thicknesses of the high acoustic impedance layer 12 and the low acoustic impedance layer 11 in the semiconductor device, that is, the high acoustic impedance layer 12 and the low acoustic impedance layer 11 of different thicknesses can be designed according to actual needs.

[0029] 4, in one specific embodiment, the high acoustic impedance layer 12 has a greater thickness closer to the piezoelectric layer 40, and the low acoustic impedance layer 11 has a greater thickness closer to the piezoelectric layer 40. That is, t LI2i <t LI2i-2 <... <t LI2 , and t HI2i-1 <t HI2i-3 <... <t HI1 Here, t LI2i is the thickness of the bottom low frequency temperature coefficient compensation layer, and t LI2 is the thickness of the topmost low frequency temperature coefficient compensation layer, and t HI2i-1 is the thickness of the bottom high frequency temperature coefficient compensation layer, and t HI1 denotes the thickness of the topmost high frequency temperature coefficient compensating layer.

[0030] In this embodiment, the thicknesses of the high acoustic impedance layer 12 and the low acoustic impedance layer 11 are not exactly the same, which can provide a more complete reflection and reduce the sensitivity of the design to non-uniformity during the process. That is, if the design is X, a slight deviation will occur during production, and the thicknesses of each acoustic impedance layer can be made different to provide a better yield rate.

[0031] As can be seen, referring to Fig. 3, in other embodiments, the thicknesses of the high acoustic impedance layer 12 and the low acoustic impedance layer 11 may be the same. For example, in one detailed embodiment, the acoustic thickness of each layer in the high and low acoustic impedance alternating layer 10 can be designed to be 1 / 4 of the period of the excited vibration mode, that is, the acoustic thickness of each layer is equal to the phase length t_p and is π / 2. However, in other embodiments, the acoustic thickness of each high and low acoustic impedance layer can be designed to be different according to the actual usage scenario and the needs of the user.

[0032] Referring to FIG. 5, in one embodiment, the resonator further includes a medium layer 70, which is disposed on a first surface of the top frequency temperature coefficient compensation layer 60, and the contact surface of the top frequency temperature coefficient compensation layer 60 with the top electrode layer 50 is the second surface of the top frequency temperature coefficient compensation layer 60, and the first surface of the top frequency temperature coefficient compensation layer 60 and the second surface of the top frequency temperature coefficient compensation layer 60 are disposed opposite to each other.

[0033] Specifically, unlike the above embodiment in which the resonant frequency of the resonator is changed by changing the thickness of the top frequency temperature coefficient compensation layer 60, in this embodiment, in the actual production process, the thickness of the top frequency temperature coefficient compensation layer 60 of each resonator is set to be the same. When a device with a different resonant frequency (specifically, a lower resonant frequency) is required, the existing laminated structure can be directly processed and a thin medium layer 70 can be directly patterned on the top of the top frequency temperature coefficient compensation layer 60 to change the resonant frequency of the acoustic device (i.e., the resonator).

[0034] The type of the medium layer 70 is not limited, and in one embodiment, the medium layer 70 may be made of Pt, Mo, Au, AlN (aluminum nitride), SiN (silicon nitride), SiO 2 It may be a film layer formed of any one or a combination of a plurality of (silicon dioxide), Ti, W, and Ru.

[0035] 6, in one embodiment, the resonant frequency of the resonator can be changed by changing the thickness of the top frequency temperature coefficient compensation layer 60, that is, the thickness of the top frequency temperature coefficient compensation layer 60 is not unique, and in the actual production process, specifically, different designs can be made according to the user's demand and use scene. Because the thickness of the top frequency temperature coefficient compensation layer 60 is not consistent between resonators with different resonant frequencies, in the actual production process, devices with different resonant frequencies can be manufactured on the same wafer so as to be adjacent to each other, which has higher production efficiency.

[0036] Referring to FIG. 7, in one embodiment, the resonator further includes a metal layer 80, the metal layer 80 is disposed on a first surface of the top electrode layer 50, the top frequency temperature coefficient compensation layer 60 is disposed on the first surface of the metal layer 80, the contact surface of the metal layer 80 with the top electrode layer 50 is the second surface of the metal layer 80, and the first surface of the metal layer 80 and the second surface of the metal layer 80 are disposed opposite to each other.

[0037] Specifically, in this embodiment, a metal layer 80 is provided between the top frequency temperature coefficient compensation layer 60 and the top electrode layer 50, thereby changing the resonant frequency of the resonator. As can be understood, the type of the metal layer 80 is not limited, and in one embodiment, the same material as the top electrode layer 50 can be adopted, and in this case, the thickness of the top electrode layer 50 of this resonator can be designed to be higher than the thickness of the top electrode layer 50 of other resonators during processing. In another embodiment, the metal layer 80 can be formed of a material different from that of the top electrode layer 50, and in this case, after forming the top electrode layer 50, a thin metal layer 80 can be subsequently formed of another metal material in the resonator that needs to change the resonant frequency.

[0038] In addition, referring to FIG. 8 , in another embodiment, the resonant frequency of the resonator can be changed by etching the top electrode layer 50, that is, in the production process, multiple resonators are processed simultaneously, and after the processing of the top electrode layer 50 is completed all at once, an additional etching process can be performed for the resonators that need to change the resonant frequency to reduce the thickness of the top electrode layer 50.

[0039] Furthermore, in one embodiment, different metal materials can be used to form the bottom electrode layer 30 and / or the top electrode layer 50 for different resonators, and the material type of one or two electrodes can be changed to form resonators with similarly different resonant frequencies.

[0040] In one embodiment, the projections of the bottom electrode layer 30 and the top electrode layer 50 in a direction perpendicular to the substrate are both polygonal.

[0041] Specifically, referring to FIG. 9 and FIG. 10, FIG. 9 shows that the projections of the bottom electrode layer 30 and the top electrode layer 50 in a direction perpendicular to the substrate are both quadrangular, and FIG. 10 shows that the projections of the bottom electrode layer 30 and the top electrode layer 50 in a direction perpendicular to the substrate are both hexagonal. In this embodiment, the projections of the bottom electrode layer 30 and the top electrode layer 50 in a direction perpendicular to the substrate are both polygonal, and may be any other polygonal shape having multiple sides, such as a square, a rectangle, a trapezoid, etc. That is, in this case, the bottom electrode layer 30 and the top electrode layer 50 are both polygonal prism structures, and the height of the polygonal prism structure is the thickness of the bottom electrode layer 30 and the top electrode layer 50. As can be understood, the polygon in this embodiment may be a quadrangle, a pentagon, a hexagon, etc. Then, it may be from 4 to infinity to form a structure similar to a circle or an ellipse.

[0042] In one embodiment, the alternating high and low acoustic impedance layer 10, the bottom frequency temperature coefficient compensation layer 20, the bottom electrode layer 30, the piezoelectric layer 40, the top electrode layer 50 and the top frequency temperature coefficient compensation layer 60 all have the same length in the same direction parallel to the substrate.

[0043] Specifically, the direction parallel to the substrate is not the only direction, but may be the length, width, or diagonal of the projection of the high and low acoustic impedance alternating layer 10, the bottom frequency temperature coefficient compensation layer 20, the bottom electrode layer 30, the piezoelectric layer 40, the top electrode layer 50, and the top frequency temperature coefficient compensation layer 60 in a direction perpendicular to the substrate. In one embodiment, if the projections of the high and low acoustic impedance alternating layer 10, the bottom frequency temperature coefficient compensation layer 20, the bottom electrode layer 30, the piezoelectric layer 40, the top electrode layer 50, and the top frequency temperature coefficient compensation layer 60 in a direction perpendicular to the substrate are all rectangular, the same direction parallel to the substrate is the width of the rectangle, and in this case, the lengths of the resonators along the width direction of the rectangle are all the same, and the corresponding cross-sectional shapes along the width direction are as shown in FIG. 1 or FIG. 3 to FIG. 4.

[0044] As can be understood, the design method of the lengths of the high and low acoustic impedance alternating layer 10, the bottom frequency temperature coefficient compensation layer 20, the bottom electrode layer 30, the piezoelectric layer 40, the top electrode layer 50 and the top frequency temperature coefficient compensation layer 60 in a direction parallel to the substrate is not unique, and in one embodiment, the lengths of the high and low acoustic impedance alternating layer 10, the bottom frequency temperature coefficient compensation layer 20, the bottom electrode layer 30, the piezoelectric layer 40, the top electrode layer 50 and the top frequency temperature coefficient compensation layer 60 in the same direction parallel to the substrate are not completely the same.

[0045] Specifically, referring to FIG. 11 or FIG. 12, the high and low acoustic impedance alternating layer 10, the bottom frequency temperature coefficient compensation layer 20, the bottom electrode layer 30, the piezoelectric layer 40, the top electrode layer 50 and the top frequency temperature coefficient compensation layer 60 are stacked in order, so that when the dimensions of each layer are different, in order to avoid the presence of gaps between each stack, the stack located at the bottom among the stack located at the bottom with a larger width and the stack located at the top with a smaller width are designed to wrap the stack located at the top, or the stack located at the top among the stack located at the top with a larger width and the stack located at the bottom with a smaller width are designed to wrap the stack located at the bottom. At this time, it is recommended to refer to FIG. 2 for a plan view corresponding to the resonator. The cross-sectional shape in the AA' direction of the resonator is similar to the cross-sectional shape of each layer in the above embodiment in the same direction parallel to the substrate, and it is recommended to refer to FIG. 1 or FIG. 3 to 8 for both. The cross-sectional shape in the BB' direction may be such that, as shown in Figure 11 or Figure 12, stacks with larger layer dimensions envelop stacks with smaller layer dimensions, and the bottom electrode layer and each high acoustic impedance layer may have widths that increase or decrease sequentially from top to bottom, or the width sizes may be randomly arranged, as long as it is ensured that the widths of each stack in the same direction parallel to the substrate are not exactly the same.

[0046] 13 to 15, Fig. 13 and Fig. 14 are respectively simulation responses of characteristic admittance of the resonator according to the present application at different frequencies, and by natural frequency simulation, it is realized to have an optimal thickness of the laminated reflection layer at a resonant frequency of about 3.5 GHz, and Fig. 15 shows a schematic diagram of stress distribution of the resonator provided by the present application, and from the diagram, the distribution of the minimum stress -Max to the maximum stress +Max of the resonator can be obtained.

[0047] According to the above resonator, a new type of resonator is formed by stacking high and low acoustic impedance alternating layer 10, bottom frequency temperature coefficient compensation layer 20, bottom electrode layer 30, piezoelectric layer 40, top electrode layer 50 and top frequency temperature coefficient compensation layer 60 on a substrate in sequence through a special microfabrication process flow. Due to this special stacking geometric structure, the resonator can simultaneously exhibit good characteristics of low loss, wide band, low temperature sensitivity and small size, and has excellent operation reliability.

[0048] The electronic device includes the resonator. Specifically, the specific structure of the resonator in the electronic device of this embodiment is, as shown in each of the above embodiments and drawings, a high-low acoustic impedance alternating layer 10 provided on a substrate, a bottom frequency temperature coefficient compensation layer 20 provided on a first surface of the high-low acoustic impedance alternating layer 10, the contact surface of the high-low acoustic impedance alternating layer 10 with the substrate being the second surface of the high-low acoustic impedance alternating layer 10, the bottom frequency temperature coefficient compensation layer 20 arranged so that the first surface of the high-low acoustic impedance alternating layer 10 and the second surface of the high-low acoustic impedance alternating layer 10 face each other, and a bottom electrode layer 30 provided on the first surface of the bottom frequency temperature coefficient compensation layer 20, the contact surface of the bottom frequency temperature coefficient compensation layer 20 with the high-low acoustic impedance alternating layer 10 being the second surface of the bottom frequency temperature coefficient compensation layer 20, and the first surface of the bottom frequency temperature coefficient compensation layer 20 and the bottom frequency temperature coefficient compensation layer 20 are arranged so that the bottom frequency temperature coefficient compensation layer 20 and the bottom frequency temperature coefficient compensation layer 20 face each other. the first surface of the piezoelectric layer 40 is disposed opposite the second surface of the bottom electrode layer 30; a piezoelectric layer 40 provided on the first surface of the bottom electrode layer 30, the contact surface of the bottom electrode layer 30 with the bottom frequency temperature coefficient compensation layer 20 being the second surface of the bottom electrode layer 30, and the first surface of the bottom electrode layer 30 and the second surface of the bottom electrode layer 30 being disposed opposite each other; a top electrode layer 50 provided on the first surface of the piezoelectric layer 40, the contact surface of the piezoelectric layer 40 with the bottom electrode layer 30 being the second surface of the piezoelectric layer 40, and the first surface of the piezoelectric layer 40 and the second surface of the piezoelectric layer 40 being disposed opposite each other; and a top frequency temperature coefficient compensation layer 60 provided on the first surface of the top electrode layer 50, the contact surface of the top electrode layer 50 with the piezoelectric layer 40 being the second surface of the top electrode layer 50, and the first surface of the top electrode layer 50 and the second surface of the top electrode layer 50 being disposed opposite each other.

[0049] Due to the special laminated geometric structure, the resonator can simultaneously exhibit good characteristics of low loss, wide bandwidth, low temperature sensitivity and small size, and has excellent operational reliability. When the resonator is applied to electronic devices, it can effectively improve the use reliability of the electronic devices and make the electronic devices meet the requirements of the 5G standard.

[0050] The technical features of the above embodiments can be combined in any combination, and for the sake of brevity, a description is not given of all possible combinations of the technical features in the above embodiments; however, as long as there is no contradiction in the combinations of these technical features, they should all be considered to be within the scope of the present specification.

[0051] The above examples only represent some embodiments of the present application, and the description is relatively specific and detailed, but this should not be understood as a limitation on the scope of the claims. Furthermore, those skilled in the art can make some modifications and improvements without departing from the concept of the present application, all of which are within the scope of protection of the present application. Therefore, the scope of protection of the patent of the present application is based on the appended claims.

Claims

1. A high and low acoustic impedance alternating layer provided on a substrate; a bottom frequency temperature coefficient compensation layer provided on a first surface of the high and low acoustic impedance alternating layer, the contact surface of the high and low acoustic impedance alternating layer with the substrate being a second surface of the high and low acoustic impedance alternating layer, and the first surface of the high and low acoustic impedance alternating layer and the second surface of the high and low acoustic impedance alternating layer being disposed opposite each other; a bottom electrode layer provided on a first surface of the bottom frequency temperature coefficient compensation layer, the contact surface of the bottom frequency temperature coefficient compensation layer with the high and low acoustic impedance alternating layer being a second surface of the bottom frequency temperature coefficient compensation layer, and the first surface of the bottom frequency temperature coefficient compensation layer and the second surface of the bottom frequency temperature coefficient compensation layer being disposed opposite each other; a piezoelectric layer provided on a first surface of the bottom electrode layer, the contact surface of the bottom electrode layer with the bottom frequency temperature coefficient compensation layer being a second surface of the bottom electrode layer, and the first surface of the bottom electrode layer and the second surface of the bottom electrode layer being disposed opposite each other; a top electrode layer provided on a first surface of the piezoelectric layer, the contact surface of the piezoelectric layer with the bottom electrode layer being a second surface of the piezoelectric layer, and the first surface of the piezoelectric layer and the second surface of the piezoelectric layer being disposed opposite each other; a top frequency temperature coefficient compensation layer provided on a first surface of the top electrode layer, the contact surface of the top electrode layer with the piezoelectric layer being a second surface of the top electrode layer, and the first surface of the top electrode layer and the second surface of the top electrode layer being disposed opposite each other; a metal layer disposed on a first surface of the top electrode layer; the top frequency temperature coefficient compensation layer is disposed on a first surface of the metal layer; A contact surface of the metal layer with the top electrode layer is a second surface of the metal layer, and the first surface of the metal layer and the second surface of the metal layer are disposed opposite to each other; The high and low acoustic impedance alternating layers include a high acoustic impedance layer and a low acoustic impedance layer, the acoustic impedance of the high acoustic impedance layer is higher than the acoustic impedance of the low acoustic impedance layer; The high acoustic impedance layers and the low acoustic impedance layers are alternately stacked, a contact layer between the high and low acoustic impedance alternating layer and the substrate is a low acoustic impedance layer; A contact layer between the high and low acoustic impedance alternating layer and the bottom frequency temperature coefficient compensation layer is a high acoustic impedance layer.

1. A resonator comprising:

2. the high acoustic impedance layer is not equal in thickness to the low acoustic impedance layer; 2. The resonator according to claim 1 .

3. The high acoustic impedance layer has the same thickness as the low acoustic impedance layer.

2. The resonator according to claim 1 .

4. a medium layer provided on a first surface of the top frequency temperature coefficient compensation layer; a contact surface of the top frequency temperature coefficient compensation layer with the top electrode layer is a second surface of the top frequency temperature coefficient compensation layer; The first surface of the top frequency temperature coefficient compensation layer and the second surface of the top frequency temperature coefficient compensation layer are disposed opposite to each other; 2. The resonator according to claim 1 .

5. The projections of the bottom electrode layer and the top electrode layer in a direction perpendicular to the substrate are both polygonal.

2. The resonator according to claim 1 .

6. the high and low acoustic impedance alternating layer, the bottom frequency temperature coefficient compensation layer, the bottom electrode layer, the piezoelectric layer, the top electrode layer and the top frequency temperature coefficient compensation layer all have the same length in the same direction parallel to the substrate; 2. The resonator according to claim 1 .

7. the high and low acoustic impedance alternating layer, the bottom frequency temperature coefficient compensation layer, the bottom electrode layer, the piezoelectric layer, the top electrode layer and the top frequency temperature coefficient compensation layer are not the same in length in the same direction parallel to the substrate; 2. The resonator according to claim 1 .

8. An electronic device comprising the resonator according to any one of claims 1 to 7.

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