Resonator and preparation method thereof

Abstract

The invention discloses a resonator and a preparation method thereof. The resonator comprises a substrate, a transducer stacking structure and a temperature compensation layer, the transducer stacking structure comprises a bottom electrode layer, a piezoelectric layer and a top electrode layer which are sequentially stacked on one side of the substrate; the temperature compensation layer comprises a first compensation branch and a second compensation branch which are connected with each other; the first compensation subsection is arranged in the top electrode layer, and the second compensation subsection is arranged between the piezoelectric layer and the top electrode layer; the transducer stacking structure comprises a working area; the projection of the first compensation branch on the plane where the substrate is located covers the projection of the working area on the plane where the substrate is located. According to the technical scheme, the first compensation branch is embedded in the top electrode layer, and the second compensation branch is arranged between the piezoelectric layer and the top electrode layer, so that the problem of temperature drift of the resonator caused by temperature change is solved, the top electrode layer is prevented from being divided into two independent parts, and electrical loss and reduction of the Q value of the resonator are avoided.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of resonators, and in particular to a resonator and a preparation method thereof. BACKGROUND

[0002] Due to temperature changes and current application of high-power devices, the temperature of the resonator changes, which is particularly significant in more extreme environments. The temperature change of the resonator causes a series of corresponding changes in the physical properties of the material, resulting in a shift in the resonant frequency of the resonator. SUMMARY

[0003] The present application provides a resonator and a preparation method thereof to solve the problem of temperature drift of the resonator caused by temperature changes.

[0004] According to an aspect of the present application, a resonator is provided, comprising: a substrate, a transducer stack structure, and a temperature compensation layer.

[0005] The transducer stack structure comprises a bottom electrode layer, a piezoelectric layer, and a top electrode layer which are sequentially stacked on one side of the substrate.

[0006] The temperature compensation layer comprises a first compensation subpart and a second compensation subpart which are connected to each other; the first compensation subpart is arranged inside the top electrode layer, and the second compensation subpart is arranged between the piezoelectric layer and the top electrode layer.

[0007] The transducer stack structure comprises a working area; along the thickness direction of the film bulk acoustic resonator, the projection of the first compensation subpart on the plane of the substrate covers the projection of the working area on the plane of the substrate.

[0008] The temperature-elasticity coefficient of the temperature compensation layer is greater than zero, and the temperature-elasticity coefficient of the transducer stack structure is less than zero.

[0009] Optionally, the resonator further comprises an air bridge formed by the top electrode layer and the piezoelectric layer, and the second compensation subpart at least partially fills the air bridge.

[0010] Optionally, the second compensation subpart is arranged in the air bridge.

[0011] Optionally, the projection of the second compensation subpart on the plane of the substrate does not overlap with the projection of the working area on the plane of the substrate; and the second compensation subpart is arranged around the first compensation subpart.

[0012] Optionally, the resonator further comprises a third compensation subpart.

[0013] The third compensation subpart is arranged between the piezoelectric layer and the top electrode layer and is not connected to the first compensation subpart and the second compensation subpart; the projection of the third compensation subpart on the plane of the substrate does not overlap with the projection of the working area on the plane of the substrate; and the third compensation subpart is arranged around the second compensation subpart.

[0014] Optionally, the third compensation part is a phononic crystal.

[0015] According to another aspect of the present application, a method for manufacturing a resonator is provided, which is applied to the resonator;

[0016] The method for manufacturing a resonator comprises:

[0017] providing a substrate and sequentially manufacturing a bottom electrode layer, a piezoelectric layer and a first electrode layer on one side of the substrate; wherein the top electrode layer comprises the first electrode layer and a second electrode layer;

[0018] manufacturing a temperature compensation layer on a side of the first electrode layer away from the piezoelectric layer;

[0019] manufacturing the second electrode layer on a side of the temperature compensation layer away from the first electrode layer;

[0020] wherein the temperature compensation layer comprises a first compensation part and a second compensation part connected to each other; the first compensation part is arranged inside the top electrode layer, and the second compensation part is arranged between the piezoelectric layer and the top electrode layer; along a thickness direction of the film bulk acoustic resonator, a projection of the first compensation part on a plane where the substrate is located covers a projection of the working area on the plane where the substrate is located.

[0021] Optionally, the step of providing a substrate and sequentially manufacturing a bottom electrode layer, a piezoelectric layer and a first electrode layer on one side of the substrate comprises:

[0022] providing a substrate and sequentially manufacturing a bottom electrode layer and a piezoelectric layer on one side of the substrate;

[0023] depositing a sacrificial layer on a side of the piezoelectric layer away from the substrate and patterning the sacrificial layer;

[0024] depositing the first electrode layer on a side of the piezoelectric layer away from the substrate;

[0025] After the step of manufacturing the second electrode layer on a side of the temperature compensation layer away from the first electrode layer, the method further comprises:

[0026] releasing the sacrificial layer to form an air bridge.

[0027] Optionally, the step of providing a substrate and sequentially manufacturing a bottom electrode layer, a piezoelectric layer and a first electrode layer on one side of the substrate comprises:

[0028] providing a substrate and sequentially manufacturing a bottom electrode layer and a piezoelectric layer on one side of the substrate;

[0029] depositing a sacrificial layer on a side of the piezoelectric layer away from the substrate and patterning the sacrificial layer; wherein the material of the sacrificial layer is the same as the material of the temperature compensation layer;

[0030] depositing the first electrode layer on a side of the piezoelectric layer away from the substrate.

[0031] Optionally, a temperature compensation layer is prepared on the side of the first electrode layer away from the piezoelectric layer, comprising:

[0032] A temperature compensation layer is prepared on the side of the first electrode layer away from the piezoelectric layer, and the temperature compensation layer is patterned to form a third compensation subpart; wherein the third compensation subpart is arranged between the piezoelectric layer and the top electrode layer and is not connected to the first compensation subpart and the second compensation subpart; the third compensation subpart is arranged around the second compensation subpart.

[0033] The technical solution of the present application improves the problem of temperature drift of the resonator caused by temperature change by embedding the first compensation subpart in the top electrode layer and arranging the second compensation subpart between the piezoelectric layer and the top electrode layer, while avoiding the separation of the top electrode layer into two independent parts and the reduction of electrical loss and resonator Q value.

[0034] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the present application, nor is it used to limit the scope of the present application. Other features of the present application will become apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0036] Figure 1 is a structural schematic diagram of a first resonator according to an embodiment of the present application;

[0037] Figure 2 is a structural schematic diagram of a second resonator according to an embodiment of the present application;

[0038] Figure 3 is a structural schematic diagram of a third resonator according to an embodiment of the present application;

[0039] Figure 4 is a flowchart of a preparation method of the first resonator according to an embodiment of the present application;

[0040] Figure 5 is a structural diagram corresponding to the preparation method of the first resonator according to an embodiment of the present application;

[0041] Figure 6 is a flowchart of a preparation method of the second resonator according to an embodiment of the present application;

[0042] Figure 7is a structure diagram corresponding to a preparation method of a second resonator according to an embodiment of the present application;

[0043] Figure 8 is a flow chart of a preparation method of a third resonator according to an embodiment of the present application;

[0044] Figure 9 is a structure diagram corresponding to the preparation method of the third resonator according to the embodiment of the present application;

[0045] Figure 10 is a flow chart of a preparation method of a fourth resonator according to an embodiment of the present application;

[0046] Figure 11 is a structure diagram corresponding to the preparation method of the fourth resonator according to the embodiment of the present application. DETAILED DESCRIPTION

[0047] In order to make the personnel in the technical field better understand the present application scheme, the technical scheme in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by the person skilled in the art without creative labor should belong to the scope of protection of the present application.

[0048] It should be noted that the terms "first", "second" and the like in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0049] Figure 1 is a structure diagram of a first resonator according to an embodiment of the present application. As shown in the figure, the resonator comprises: Figure 1

[0050] a substrate 1, a transducer stack structure 2 and a temperature compensation layer 3;

[0051] The transducer stack structure 2 comprises a bottom electrode layer 21, a piezoelectric layer 22 and a top electrode layer 23 which are sequentially stacked on one side of the substrate 1; ​

[0052] The temperature compensation layer 3 comprises a first compensation sub-part 31 and a second compensation sub-part 32 connected with each other; the first compensation sub-part 31 is arranged inside the top electrode layer 23, and the second compensation sub-part 32 is arranged between the piezoelectric layer 22 and the top electrode layer 23;

[0053] The transducer stack structure 2 comprises a working area; in the thickness direction of the film bulk acoustic resonator, the projection of the first compensation sub-part 31 on the plane of the substrate 1 covers the projection of the working area on the plane of the substrate 1.

[0054] The temperature-elasticity coefficient of the temperature compensation layer 3 is greater than zero, and the temperature-elasticity coefficient of the transducer stack structure 2 is less than zero.

[0055] The substrate 1 can be the base of the resonator. The transducer stack structure 2 comprises a bottom electrode layer 21, a piezoelectric layer 22 and a top electrode layer 23 arranged in sequence on one side of the substrate 1. The working area of the transducer stack structure 2 can be the overlapping area of the bottom electrode layer 21, the piezoelectric layer 22 and the top electrode layer 23, which is the main resonant area, and the inverse piezoelectric effect converts electrical energy into acoustic waves to form resonance.

[0056] The temperature compensation layer 3 can be made of a material with a positive temperature coefficient. The temperature-elasticity coefficient can be used to represent the change of Young's modulus affected by temperature. The temperature-elasticity coefficient of the temperature compensation layer 3 is a positive temperature-elasticity coefficient, and the temperature-elasticity coefficient in the transducer stack structure 22 is a negative temperature-elasticity coefficient. The first compensation sub-part 31 is arranged in the top electrode layer 23, and in the thickness direction of the film bulk acoustic resonator, the projection of the first compensation sub-part 31 on the plane of the substrate 1 covers the projection of the working area on the plane of the substrate 1, that is, the first compensation sub-part 31 covers the working area. The first compensation sub-part 31 can compensate for the negative temperature-elasticity coefficient of the transducer stack structure 2 through its own elastic change, thereby reducing the influence of temperature on the performance of the film bulk acoustic resonator and improving the communication anti-interference performance of the film bulk acoustic resonator. However, arranging the whole temperature compensation layer 3 in the top electrode layer 23 in the prior art will divide the top electrode layer 23 into two parts, which will further increase the electrical loss of the top electrode. Therefore, in the embodiment of the present application, the second compensation sub-part 32 is arranged, and the second compensation sub-part 32 is arranged between the piezoelectric layer 22 and the top electrode layer 23 and connected with the first compensation sub-part 31. The first compensation sub-part 31 and the second compensation sub-part 32 can be integrally arranged. Arranging the temperature compensation layer 3 partially in the top electrode layer 23 in this way will not increase the electrical loss, and will not affect the Q value of the resonator.

[0057] For example, in the preparation of the resonator, the bottom electrode layer 21, the piezoelectric layer 22 and the first electrode layer 231 can be first deposited on one side of the substrate 1, wherein the first electrode layer 231 can be part of the top electrode layer 23, and the first electrode layer 231 partially covers the piezoelectric layer 22. Then, the temperature compensation layer 3 is deposited, so that the first compensation part 31 of the temperature compensation layer 3 covers the working area, and the second compensation part 32 covers the piezoelectric layer 22. Then, the second electrode layer 232 is deposited on one side of the first electrode layer 231, and the second electrode layer 232 covers the temperature compensation layer 3, thereby obtaining a complete resonator structure.

[0058] The technical scheme of the embodiment of the present application improves the problem of temperature drift of the resonator caused by temperature change by embedding the first compensation part in the top electrode layer and arranging the second compensation part between the piezoelectric layer and the top electrode layer, and avoids the separation of the top electrode layer into two independent parts, thereby avoiding the electrical loss and the reduction of the Q value of the resonator.

[0059] Optionally, continuing to refer to Figure 1 As shown, the air bridge 41 formed by the top electrode layer 23 and the piezoelectric layer 22 is further included, and the second compensation part 32 at least partially fills in the air bridge 41.

[0060] As shown, the air bridge 41 formed by the top electrode layer 23 and the piezoelectric layer 22 is further included, and the second compensation part 32 at least partially fills in the air bridge 41.

[0061] Specifically, after the preparation of the piezoelectric layer 22, the air bridge 41 can be prepared by depositing a sacrificial layer on the piezoelectric layer 22, and after the preparation of the top electrode layer 23, the air bridge 41 is formed by releasing part of the sacrificial layer, and the remaining part fills in the air bridge as the second compensation part, so that the second compensation part 32 can avoid the electrical loss and the reduction of the Q value of the resonator, and the stability of the air bridge 41 is improved, the energy transfer efficiency is improved, and the Q value of the resonator is improved.

[0062] It can be understood that due to the existence of the air bridge 41, the propagation loss of the transverse acoustic wave can be reduced, the energy transfer efficiency can be improved, and the Q value of the resonator can be improved.

[0063] Optionally, Figure 2 is a structural schematic diagram of a second resonator provided according to the embodiment of the present application, as Figure 2 As shown, the second compensation part 32 is arranged in the air bridge 41.

[0064] The second compensation part 32 is arranged in the air bridge 41, that is, after the piezoelectric layer 22 is prepared, the temperature compensation layer 3 is deposited to form the second compensation part 32, and then the first electrode layer 231, the first compensation part 31 and the second electrode layer 232 are prepared after the second compensation layer is prepared. The second compensation part 32 in the air bridge 41 is not released after the second electrode layer 232 is prepared, so that the second compensation part 32 is filled in the air bridge 41, so that the second compensation part 32 can avoid electrical loss and reduce the Q value of the resonator, and the stability of the air bridge 41 is improved, the energy transmission efficiency is improved, and the Q value of the resonator is improved. At the same time, it also plays a certain heat dissipation role to a certain extent.

[0065] In some embodiments, an air wing 42 can also be arranged between the piezoelectric layer and the top electrode layer.

[0066] The technical scheme of the embodiment of the present application arranges the second compensation part in the air bridge, which can avoid electrical loss and reduce the Q value of the resonator, improve the stability of the air bridge, improve the energy transmission efficiency, and improve the Q value of the resonator.

[0067] Optionally, continuing to refer to Figure 1 As shown, the projection of the second compensation part 32 on the plane of the substrate 1 does not overlap with the projection of the working area on the plane of the substrate 1; and the second compensation part 32 is arranged around the first compensation part 31.

[0068] The second compensation part 32 can be arranged in the non-working area, that is, the projection of the second compensation part 32 on the plane of the substrate 1 does not overlap with the projection of the working area on the plane of the substrate 1, and the second compensation part 32 is arranged around the first compensation part 31 and is integrated.

[0069] Specifically, in the actual preparation process, the temperature compensation layer 3 can be deposited to cover the working area with the first compensation part 31 and cover the non-working area with the second compensation part 32, which are prepared by the same process step.

[0070] It can be understood that the existing technology mainly applies the technical route of low-temperature sintering ceramic filter to 5G, satellite communication, Internet of Things and other new frequency bands. This route can realize high-density integration due to the multi-layer structure, meet the requirements of small size and high frequency of 5G millimeter wave, but the technical route has the problem of insufficient isolation, that is, the frequency band isolation does not meet the high-frequency passband high suppression condition. In the embodiment of the present application, the second compensation part 32 is arranged in the non-working area, so that the dielectric constant can be increased, the isolation can be increased, and the quality factor of the resonator can be improved. At the same time, during the working process of the top electrode layer 23 and the substrate 1, leakage current cannot be avoided, and the existence of the second compensation part 32 can reduce the influence of the leakage current.

[0071] The technical scheme of the embodiment of the present application sets the second compensation part in the non-working area, improves the dielectric constant of the resonator, increases the isolation, improves the quality factor of the resonator, and reduces the influence of the leakage current.

[0072] Optionally, Figure 3 is a structural diagram of a third resonator according to an embodiment of the present application, as Figure 3 indicated, further comprising a third compensation part 33;

[0073] The third compensation part 33 is arranged between the piezoelectric layer 22 and the top electrode layer 23 and is not connected to the first compensation part 31 and the second compensation part 32; the projection of the third compensation part 33 on the plane of the substrate 1 does not overlap the projection of the working area on the plane of the substrate 1; and the third compensation part 33 surrounds the second compensation part 32.

[0074] The third compensation part 33 can also be made of the same material as the temperature compensation layer 3 and is prepared in the same process flow as the first compensation part 31 and the second compensation part 32. The third compensation part 33 is arranged in the non-working area between the piezoelectric layer 22 and the top electrode layer 23 and surrounds the second compensation part 32.

[0075] Specifically, in the actual preparation process, the third compensation part 33 can be formed by depositing the temperature compensation layer 3 and etching the temperature compensation layer 3. The first compensation part 31 covers the working area, and the second compensation part 32 and the third compensation part 33 cover the non-working area.

[0076] It can be understood that, due to the gap between the third compensation part 33 and the second compensation part 32, the third compensation part 33 can reflect the lateral acoustic wave. In some embodiments, the size of the gap can be adjusted to adjust the efficiency of reflecting the lateral acoustic wave.

[0077] In some embodiments, the third compensation part 33 is a phononic crystal. The phononic crystal can be a composite material with a spatial periodic structure and an elastic wave band gap. The phononic crystal can generate a band gap to control the propagation of elastic waves, further improving the performance of the resonator.

[0078] The technical scheme of the embodiment of the present application sets the third compensation part to further adjust the reflected lateral wave, increases the isolation, and reduces the influence of the leakage current.

[0079] Based on the same inventive concept, Figure 4 is a flow chart of a preparation method of a first resonator according to an embodiment of the present application, Figure 5 is a structural diagram of a preparation method of a first resonator according to an embodiment of the present application, in combination with Figure 4 and Figure 5As shown, the embodiment of the present application also provides a preparation method of the resonator, which is applied to the resonator.

[0080] The preparation method comprises:

[0081] S10, providing a substrate and sequentially preparing a bottom electrode layer, a piezoelectric layer and a first electrode layer on one side of the substrate. As shown in (a) of FIG. 1. Figure 5 The top electrode layer 23 comprises the first electrode layer 231 and the second electrode layer 232.

[0082] The top electrode layer 23 comprises the first electrode layer 231 and the second electrode layer 232, and the first electrode layer 231 covers the working area and exposes part of the non-working area. That is, after sequentially preparing the bottom electrode layer 21, the piezoelectric layer 22 and the first electrode layer 231, the first electrode layer 231 is etched to expose part of the non-working area.

[0083] S11, preparing a temperature compensation layer on the side of the first electrode layer away from the piezoelectric layer. As shown in (b) of FIG. 1. Figure 5

[0084] The temperature compensation layer 3 is prepared on the side of the first electrode layer 231 away from the piezoelectric layer 22. The temperature compensation layer 3 covers the working area and also covers the non-working area exposed by the first electrode layer 231, thereby forming the first compensation subpart 31 and the second compensation subpart 32 connected to each other. The first compensation subpart 31 is arranged inside the top electrode layer 23, and the second compensation subpart 32 is arranged between the piezoelectric layer 22 and the top electrode layer 23.

[0085] S12, preparing a second electrode layer on the side of the temperature compensation layer away from the first electrode layer. As shown in (c) of FIG. 1. Figure 5

[0086] After the first temperature compensation layer 3 is prepared, the second electrode layer 232 is continuously prepared. The second electrode layer 232 covers the first compensation subpart 31 and the second compensation subpart 32.

[0087] The temperature compensation layer 3 comprises the first compensation subpart 31 and the second compensation subpart 32 connected to each other. The first compensation subpart 31 is arranged inside the top electrode layer 23, and the second compensation subpart 32 is arranged between the piezoelectric layer 22 and the top electrode layer 23. In the thickness direction of the film bulk acoustic resonator, the projection of the first compensation subpart 31 on the plane of the substrate 1 covers the projection of the working area on the plane of the substrate 1.

[0088] ​​Specifically, in the preparation process of the resonator, a bottom electrode layer 21, a piezoelectric layer 22 and a first electrode layer 231 can be first deposited on one side of the substrate 1, wherein the first electrode layer 231 can be part of the top electrode layer 23, and the first electrode layer 231 partially covers the piezoelectric layer 22. Then, a temperature compensation layer 3 is deposited, so that the first compensation part 31 of the temperature compensation layer 3 covers the working area, and the second compensation part 32 covers the piezoelectric layer 22. Then, a second electrode layer 232 is deposited on one side of the first electrode layer 231, and the second electrode layer 232 covers the temperature compensation layer 3, thereby obtaining a complete resonator structure.

[0089] The technical scheme of the embodiment of the present application improves the problem of temperature drift of the resonator caused by temperature change by embedding the first compensation part in the top electrode layer and arranging the second compensation part between the piezoelectric layer and the top electrode layer, and avoids the top electrode layer being divided into two independent parts, thereby avoiding the reduction of electrical loss and the Q value of the resonator.

[0090] On the basis of the above embodiment, Figure 6 is a second resonator preparation method flow chart provided according to the embodiment of the present application, Figure 7 is a structure diagram corresponding to the second resonator preparation method provided according to the embodiment of the present application, which is combined with Figure 6 and Figure 7 , the preparation method comprises the following steps.

[0091] S20, providing a substrate and sequentially preparing a bottom electrode layer and a piezoelectric layer on one side of the substrate. As shown in step (d) of Figure 7 .

[0092] S21, depositing a sacrificial layer on the side of the piezoelectric layer away from the substrate and patterning the sacrificial layer. As shown in step (e) of Figure 7 .

[0093] After the preparation of the piezoelectric layer 22 is completed, the air bridge 41 can also be prepared by depositing a sacrificial layer on the piezoelectric layer 22, and the shape of the air bridge 41 is obtained by patterning the sacrificial layer.

[0094] S22, depositing a first electrode layer on the side of the piezoelectric layer away from the substrate. As shown in step (f) of Figure 7 .

[0095] S23, preparing a temperature compensation layer on the side of the first electrode layer away from the piezoelectric layer. As shown in step (g) of Figure 7 .

[0096] S24, preparing a second electrode layer on the side of the temperature compensation layer away from the first electrode layer. As shown in step (h) of Figure 7 .

[0097] S25, releasing the sacrificial layer to form an air bridge. As shown in Figure 7S30, providing a substrate and preparing a bottom electrode layer and a piezoelectric layer on one side of the substrate.

[0098] After the top electrode layer 23 is prepared, the air bridge 41 is formed by releasing the sacrificial layer.

[0099] The technical solution of the embodiment of the present application prepares an air bridge, and due to the existence of the air bridge, the propagation loss of the transverse acoustic wave is reduced, the energy transfer efficiency is improved, and the Q value of the resonator is improved.

[0100] On the basis of the above embodiment, Figure 8 is a third resonator preparation method flowchart provided by the embodiment of the present application, Figure 9 is a structure diagram corresponding to the third resonator preparation method provided by the embodiment of the present application, which is combined with Figure 8 and Figure 9 The preparation method comprises:

[0101] S30, providing a substrate and preparing a bottom electrode layer and a piezoelectric layer on one side of the substrate. As shown in Figure 9 (j) of FIG. 1.

[0102] S31, depositing a sacrificial layer on the side of the piezoelectric layer away from the substrate and patterning the sacrificial layer. As shown in Figure 9 (k) of FIG. 1. Wherein the material of the sacrificial layer is the same as that of the temperature compensation layer 3.

[0103] Wherein the material of the sacrificial layer is the same as that of the temperature compensation layer 3, and the sacrificial layer is set as the second compensation layer.

[0104] S32, depositing a first electrode layer on the side of the piezoelectric layer away from the substrate. As shown in Figure 9 (l) of FIG. 1.

[0105] After the sacrificial layer is prepared, the first electrode layer 231 is continuously deposited, and the sacrificial layer is covered.

[0106] S33, preparing a temperature compensation layer on the side of the first electrode layer away from the piezoelectric layer. As shown in Figure 9 (m) of FIG. 1.

[0107] S34, preparing a second electrode layer on the side of the temperature compensation layer away from the first electrode layer. As shown in Figure 9 (n) of FIG. 1.

[0108] Wherein, after the second electrode layer 232 is prepared, the second compensation part 32 in the air bridge 41 is not released, and the second compensation part 32 is filled in the air bridge 41, so that the second compensation part 32 can avoid electrical loss and reduce the Q value of the resonator, and the stability of the air bridge 41 is improved, the energy transfer efficiency is improved, and the Q value of the resonator is improved. At the same time, it also plays a certain heat dissipation role to a certain extent.

[0109] The technical scheme of the embodiment of the present application sets the second compensation part in the air bridge, avoids electrical loss and reduction of the resonator Q value, improves the stability of the air bridge, improves the energy transmission efficiency, and improves the Q value of the resonator.

[0110] On the basis of the above embodiment, Figure 10 is a fourth resonator preparation method flowchart provided according to the embodiment of the present application, Figure 11 is a structure diagram corresponding to the fourth resonator preparation method provided according to the embodiment of the present application, in combination with Figure 10 and Figure 11 The preparation method comprises the following steps.

[0111] S40, a substrate is provided, and a bottom electrode layer, a piezoelectric layer, and a first electrode layer are sequentially prepared on one side of the substrate. As shown in the (o) step of FIG. 1. Figure 11

[0112] S41, a temperature compensation layer is prepared on the side of the first electrode layer away from the piezoelectric layer, and the temperature compensation layer is patterned to form a third compensation part. As shown in the (p) step of FIG. 1. Figure 11

[0113] The third compensation part 33 is arranged between the piezoelectric layer 22 and the top electrode layer 23 and is not connected to the first compensation part 31 and the second compensation part 32; and the third compensation part 33 is arranged around the second compensation part 32.

[0114] The material of the temperature compensation layer 3 can be the same as that of the first compensation part 31 and the second compensation part 32, and the first compensation part 31, the second compensation part 32, and the temperature compensation layer 3 are prepared in the same process flow.

[0115] S42, a second electrode layer is prepared on the side of the temperature compensation layer away from the first electrode layer. As shown in the (q) step of FIG. 1. Figure 11

[0116] Specifically, in the actual preparation process, the third compensation part 33 can be formed by depositing the temperature compensation layer 3 and etching the temperature compensation layer 3, the first compensation part 31 covers the working area, and the second compensation part 32 and the third compensation part 33 cover the non-working area.

[0117] The technical scheme of the embodiment of the present application sets the third compensation part to further play a role in adjusting the reflected transverse wave, increases the isolation degree, and reduces the influence of the leakage current.

[0118] ​​​It should be understood that the various forms of flow shown above can be used to reorder, add, or remove steps. For example, the steps recited in the present application can be performed in parallel, in series, or in a different order, as long as the desired results of the technical solutions of the present application can be achieved, which are not limited herein.

[0119] The above detailed description does not constitute a limitation on the protection scope of the present application. Those skilled in the art should understand that various modifications, combinations, sub-combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent replacements, and improvements made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A resonator characterized by, Comprise: a substrate, a transducer stack structure and a temperature compensation layer; the transducer stack structure comprises a bottom electrode layer, a piezoelectric layer and a top electrode layer which are sequentially stacked on one side of the substrate; the temperature compensation layer comprises a first compensation subpart and a second compensation subpart which are connected to each other; the first compensation subpart is arranged inside the top electrode layer, and the second compensation subpart is arranged between the piezoelectric layer and the top electrode layer; the transducer stack structure comprises a working area; along the thickness direction of the film bulk acoustic resonator, the projection of the first compensation subpart on the plane of the substrate covers the projection of the working area on the plane of the substrate; the temperature-elasticity coefficient of the temperature compensation layer is greater than zero, and the temperature-elasticity coefficient of the transducer stack structure is less than zero.

2. The resonator of claim 1, wherein Further comprising an air bridge formed by the top electrode layer and the piezoelectric layer, wherein the second compensation subpart at least partially fills in the air bridge.

3. The resonator of claim 2, wherein The second compensation subpart is arranged in the air bridge.

4. The resonator of claim 1, wherein The projection of the second compensation subpart on the plane of the substrate does not overlap with the projection of the working area on the plane of the substrate; the second compensation subpart is arranged around the first compensation subpart.

5. The resonator of claim 4, wherein, Further comprising a third compensation subpart; The third compensation subpart is arranged between the piezoelectric layer and the top electrode layer and is not connected to the first compensation subpart and the second compensation subpart; the projection of the third compensation subpart on the plane of the substrate does not overlap with the projection of the working area on the plane of the substrate; the third compensation subpart is arranged around the second compensation subpart.

6. The resonator of claim 5, wherein, The third compensation subpart is a phononic crystal.

7. A method of manufacturing a resonator, characterized by, Applied in the resonator of any one of claims 1-6; The preparation method comprises: providing a substrate and sequentially preparing a bottom electrode layer, a piezoelectric layer and the first electrode layer on one side of the substrate; wherein the top electrode layer comprises the first electrode layer and a second electrode layer; preparing a temperature compensation layer on the side of the first electrode layer away from the piezoelectric layer; preparing the second electrode layer on the side of the temperature compensation layer away from the first electrode layer; wherein the temperature compensation layer comprises a first compensation subpart and a second compensation subpart which are connected to each other; the first compensation subpart is arranged inside the top electrode layer, and the second compensation subpart is arranged between the piezoelectric layer and the top electrode layer; along the thickness direction of the film bulk acoustic resonator, the projection of the first compensation subpart on the plane of the substrate covers the projection of the working area on the plane of the substrate.

8. The preparation method according to claim 7, characterized in that, providing a substrate and sequentially preparing a bottom electrode layer, a piezoelectric layer and the first electrode layer on one side of the substrate, comprising: providing a substrate and sequentially preparing a bottom electrode layer and a piezoelectric layer on one side of the substrate; depositing a sacrificial layer on the side of the piezoelectric layer away from the substrate and patterning the sacrificial layer; depositing the first electrode layer on the side of the piezoelectric layer away from the substrate; after preparing the second electrode layer on the side of the temperature compensation layer away from the first electrode layer, further comprising: releasing the sacrificial layer to form an air bridge.

9. The preparation method according to claim 7, characterized in that, providing a substrate and sequentially preparing a bottom electrode layer, a piezoelectric layer and the first electrode layer on one side of the substrate, comprising: A substrate is provided and a bottom electrode layer and a piezoelectric layer are sequentially prepared on one side of the substrate; A sacrificial layer is deposited on the piezoelectric layer away from the substrate and the sacrificial layer is patterned; wherein the material of the sacrificial layer is the same as that of the temperature compensation layer; The first electrode layer is deposited on the piezoelectric layer away from the substrate.

10. The preparation method according to claim 7, characterized in that, A temperature compensation layer is prepared on the first electrode layer away from the piezoelectric layer, comprising: The temperature compensation layer is prepared on the first electrode layer away from the piezoelectric layer and the temperature compensation layer is patterned to form a third compensation subpart; wherein the third compensation subpart is arranged between the piezoelectric layer and the top electrode layer and is not connected with the first compensation subpart and the second compensation subpart; the third compensation subpart is arranged around the second compensation subpart.

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