Resonator and manufacturing method thereof, radio frequency front-end module and electronic equipment

Abstract

The invention relates to a resonator and a manufacturing method thereof, a radio frequency front-end module and electronic equipment. The manufacturing method of the resonator comprises the following steps: providing a supporting layer; a functional layer and a piezoelectric layer are prepared on the supporting layer, a blind hole is formed through etching, and the hole depth of the blind hole is larger than the sum of the thicknesses of the piezoelectric layer and the functional layer and smaller than the sum of the thicknesses of the piezoelectric layer, the functional layer and the supporting layer; an insulating layer and a metal layer are sequentially deposited in the piezoelectric layer and the blind hole, thinning is carried out after deposition is completed, and an interdigital transducer and a first bonding pad are prepared on the surface of the piezoelectric layer; the supporting layer, the functional layer and the piezoelectric layer are synchronously transferred to a transfer substrate, the piezoelectric layer is located between the supporting layer and the transfer substrate, then metal in the blind holes is exposed through etching, and a second bonding pad is prepared. According to the manufacturing method of the resonator, the metal layer is deposited in the blind hole, and the two bonding pads are arranged on the two opposite sides of the metal layer, so that the plane size occupation is reduced, and miniaturization is facilitated.

Description

Technical Field

[0001] The present application relates to the radio frequency field, and in particular to a resonator, a method for manufacturing a resonator, a radio frequency front-end module including the resonator, and an electronic device including the radio frequency front-end module. Background Art

[0002] In the field of radio frequency, the RF front-end module is usually composed of multiple resonators connected in series or in parallel. The RF front-end module can process and transmit various signals by cooperating with each other.

[0003] In the prior art, in order to realize the series or parallel connection of each resonator, each resonator is usually arranged on the surface of a substrate, and the wiring on the substrate is used to realize the electrical connection of each resonator. However, the planar size of the RF front-end module is large, which is not conducive to miniaturization. Summary of the invention

[0004] In view of the above-mentioned deficiencies in the prior art, the purpose of this application is to provide a solution that is conducive to miniaturization, which specifically includes the following technical solutions:

[0005] In a first aspect, an embodiment of the present application provides a method for manufacturing a resonator, comprising the following steps:

[0006] providing a support layer;

[0007] At least one functional layer and a piezoelectric layer are prepared on the support layer, and a blind hole is formed by etching, wherein the depth of the blind hole is greater than the sum of the thicknesses of the piezoelectric layer and the functional layer, and less than the sum of the thicknesses of the piezoelectric layer, the functional layer and the support layer;

[0008] An insulating layer and a metal layer are sequentially deposited on the surface of the piezoelectric layer and in the blind hole, and a thinning process is performed after the deposition is completed, and an interdigital transducer and a first pad are prepared on the surface of the piezoelectric layer, and the first pad is respectively connected to the interdigital transducer and the metal layer in the blind hole;

[0009] The supporting layer, functional layer and piezoelectric layer are synchronously transferred to the transfer substrate, with the piezoelectric layer located between the supporting layer and the transfer substrate. The surface of the supporting layer is then etched until the metal layer in the blind hole is exposed, and a second pad conductive to the metal layer is prepared on the surface of the supporting layer.

[0010] The manufacturing method of the resonator of the present application prepares a functional layer and a piezoelectric layer on a supporting layer, and prepares an interdigital transducer on the surface of the piezoelectric layer, so as to utilize the acoustic-to-electric conversion function of the interdigital transducer and the piezoelectric layer to realize the signal processing function of the resonator prepared by the manufacturing method of the resonator of the present application.

[0011] The manufacturing method of the resonator of the present application also deposits an insulating layer and a metal layer in the blind hole, and exposes the opposite sides of the metal layer by etching the support layer, and then respectively sets a first pad and a second pad, and makes the first pad and the interdigital transducer conductive, so that the resonator manufactured by the manufacturing method of the resonator of the present application can be electrically connected with other resonators, filters, passive components and non-filter chips along its thickness direction. This reduces the size occupied in the plane direction, which is conducive to miniaturization.

[0012] In one embodiment, the step of "providing a support layer" includes: selecting a support layer, wherein the thickness of the support layer is greater than or equal to 300 μm and less than or equal to 800 μm.

[0013] In one embodiment, the thickness of the piezoelectric layer is greater than or equal to 200 nm and less than or equal to 1000 nm; and / or the thickness of the functional layer is greater than or equal to 200 nm and less than or equal to 3000 nm.

[0014] In one embodiment, along the thickness direction of the support layer, the diameter of the opening of the blind hole is greater than the diameter of the bottom of the blind hole.

[0015] In one embodiment, the step of "preparing a barrier layer on the surface of the piezoelectric layer and in the blind hole" further includes: preparing a barrier layer on the surface of the piezoelectric layer and in the blind hole until the barrier layer at least covers the insulating layer located in the blind hole.

[0016] In one embodiment, the step of "preparing a barrier layer on the surface of the piezoelectric layer and in the blind hole" further includes: preparing a seed layer on the barrier layer until the seed layer at least covers the barrier layer in the blind hole.

[0017] In one embodiment, the step of "preparing an interdigital transducer and a first soldering pad on the surface of the piezoelectric layer" also includes: preparing a device layer on the surface of the piezoelectric layer, the device layer including each electrode finger and each bus bar of the interdigital transducer; preparing a passivation layer on the surface of the device layer, and making the passivation layer cover each electrode finger; etching the passivation layer until the surface of the piezoelectric layer is partially exposed and the metal layer is exposed, and preparing a first soldering pad on the surface of the exposed piezoelectric layer, the first soldering pad being respectively connected to the bus bar and the metal layer.

[0018] In one embodiment, the step of "synchronously transferring the support layer, the functional layer and the piezoelectric layer to the transfer substrate" includes: coating a bonding glue on the surface of the piezoelectric layer until the bonding glue covers the first pad and the interdigital transducer; and using a bonding process to bond and fix the bonding glue and the transfer substrate, wherein the bonding glue includes at least one of a heat-curing glue, an ultraviolet light-curing glue, a heat-decomposable glue and a laser-decomposable glue.

[0019] In one embodiment, after the step of "preparing a second solder pad on the surface of the supporting layer that is conductive with the metal layer", it also includes: using a debonding process to remove the bonding glue and transfer the substrate, the debonding process includes at least one of a blade-type debonding process, a chemical solvent immersion debonding process, a heating pretreatment debonding process, and a laser irradiation debonding process.

[0020] In one embodiment, the step of "etching to form a blind hole" also includes: a first etching, etching the piezoelectric layer to expose the surface of the functional layer; a second etching, etching the functional layer and the membrane layer of the functional layer away from the piezoelectric layer to form a blind hole, wherein the first etching and the second etching are performed using different etching processes.

[0021] In one embodiment, during the second etching process, at least the side wall of the functional layer corresponding to the blind hole is processed so that the roughness of the side wall of the functional layer in the blind hole is greater than the roughness of the side wall of the piezoelectric layer.

[0022] In the second aspect, an embodiment of the present application provides a resonator, including a substrate, an interdigital transducer, a conductive member, a first pad and a second pad, the substrate including a stacked base plate, at least one functional layer and a piezoelectric layer, along the thickness direction of the substrate, the first pad and the interdigital transducer are located on the surface of the piezoelectric layer, the first pad is conductively connected to the interdigital transducer, and the second pad is located on the surface of the supporting layer; the substrate is provided with a through hole, the conductive member is accommodated in the through hole, along the thickness direction of the substrate, the opposite ends of the conductive member are conductively connected to the first pad and the second pad respectively.

[0023] The resonator of the present application is provided with a through hole for accommodating a conductive member on a substrate, and a first soldering pad and a second soldering pad are provided at opposite ends of the conductive member, and an interdigital transducer conductively connected to the first soldering pad is provided, so that the electroacoustic conversion function of the resonator of the present application is realized by utilizing the interdigital transducer and the piezoelectric layer of the substrate, while the resonator of the present application can be conductively connected to an external structure through the first soldering pad and the second soldering pad, thereby reducing the planar size occupied by the resonator of the present application, which is conducive to the miniaturization of the resonator of the present application.

[0024] In one embodiment, the functional layer has two layers, the two functional layers include a first functional layer and a second functional layer, the material of the first functional layer is different from the material of the second functional layer, the first functional layer is bonded to the support layer, and the second functional layer is bonded to the piezoelectric layer; wherein the thickness of the first functional layer is greater than or equal to 200nm and less than or equal to 2000nm; and / or the thickness of the second functional layer is greater than or equal to 200nm and less than or equal to 1000nm.

[0025] In a third aspect, an embodiment of the present application provides a radio frequency front-end module, including a filter chip, the filter chip including a resonator manufactured using a resonator manufacturing method; or, including a resonator.

[0026] In one embodiment, the RF front-end module also includes a second filter chip, the pad on the second filter chip is electrically connected to the first pad on the resonator, and the preparation method of the second filter chip is different from the preparation method of the resonator.

[0027] In one embodiment, the RF front-end module also includes at least one of a passive component and a non-filter chip, the passive component and the non-filter chip are arranged on at least one side of the filter chip, the pads on the passive component and the non-filter chip are electrically connected to the first pad or the second pad, and the passive component includes at least one of a resistor, an inductor and a capacitor, and the non-filter chip includes at least one of a power amplifier, a low-noise amplifier, an RF switch, a coupler and a matching circuit.

[0028] In a fourth aspect, an embodiment of the present application provides an electronic device, including a radio frequency front-end module.

[0029] It can be understood that the RF front-end module provided in the third aspect of the present application and the electronic device provided in the fourth aspect are both more conducive to miniaturization because they use the resonator manufactured by the resonator manufacturing method provided in the first aspect of the present application, or use the resonator provided in the second aspect of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 This is a schematic diagram of the structure of a radio frequency front-end module provided in one embodiment of the present application;

[0031] Figure 2 Another structural schematic diagram of a radio frequency front-end module provided in one embodiment of the present application;

[0032] Figure 3 A schematic diagram of the wiring structure of a radio frequency front-end module provided in one embodiment of the present application;

[0033] Figure 4 A schematic diagram of the working process of a method for manufacturing a resonator provided in one embodiment of the present application;

[0034] Figure 5 This is a schematic structural diagram of a method for manufacturing a resonator provided in an embodiment of the present application after step S200 is completed;

[0035] Figure 6 This is a structural schematic diagram of a method for manufacturing a resonator provided in an embodiment of the present application after step S300 is completed;

[0036] Figure 7 A schematic diagram of a partially enlarged structure of a resonator manufacturing method provided in an embodiment of the present application after step S300 is completed;

[0037] Figure 8 This is a schematic structural diagram of a method for manufacturing a resonator provided in an embodiment of the present application after step S400 is completed;

[0038] Fig. 9 A schematic diagram of another working process of a method for manufacturing a resonator provided in one embodiment of the present application;

[0039] Fig.10 It is another schematic diagram of the working process of the method for manufacturing a resonator provided in one embodiment of the present application;

[0040] Fig.11 This is a schematic structural diagram of a method for manufacturing a resonator provided in an embodiment of the present application after step S320 is completed;

[0041] Fig.12 A schematic diagram of a partially enlarged structure of a method for manufacturing a resonator provided in an embodiment of the present application after step S320 is completed;

[0042] Fig.13 This is a schematic structural diagram of a method for manufacturing a resonator provided in an embodiment of the present application after step S330 is completed;

[0043] Fig.14 This is a schematic diagram of a partially enlarged structure of a method for manufacturing a resonator provided in an embodiment of the present application after step S330 is completed;

[0044] Fig.15 This is a schematic diagram of the structure of the resonator manufacturing method provided in one embodiment of the present application after step S340 is completed;

[0045] Fig.16 A schematic diagram of a partially enlarged structure of a method for manufacturing a resonator provided in an embodiment of the present application after step S340 is completed;

[0046] Fig.17 This is a schematic structural diagram of a method for manufacturing a resonator provided in an embodiment of the present application after step S350 is completed;

[0047] Fig.18 This is a schematic diagram of the structure of the resonator manufacturing method provided in one embodiment of the present application after step S370 is completed;

[0048] Fig.19 A schematic diagram of a partially enlarged structure of a method for manufacturing a resonator provided in an embodiment of the present application after step S370 is completed;

[0049] Fig. 20 A schematic diagram of a top view of the structure of a resonator manufacturing method provided in an embodiment of the present application after step S370 is completed;

[0050] Fig.21 A schematic diagram of the structure of a method for manufacturing a resonator provided in an embodiment of the present application during step S380;

[0051] Fig. 22 A schematic diagram of a structure of a resonator manufacturing method provided in an embodiment of the present application after step S380 is completed;

[0052] Fig.23 A schematic diagram of another working process of a method for manufacturing a resonator provided in an embodiment of the present application;

[0053] Fig.24 This is a schematic structural diagram of a method for manufacturing a resonator provided in an embodiment of the present application after step S420 is completed;

[0054] Fig.25 This is a schematic structural diagram of a method for manufacturing a resonator provided in an embodiment of the present application after step S440 is completed;

[0055] Fig.26 This is a schematic diagram of the structure of the method for manufacturing a resonator provided in one embodiment of the present application after step S460 is completed;

[0056] Fig. 27 A schematic flow chart of a method for manufacturing a resonator provided in one embodiment of the present application;

[0057] Fig.28 This is a structural schematic diagram of a method for manufacturing a resonator provided in an embodiment of the present application after step S500 is completed;

[0058] Fig.29 Another schematic diagram of a process for manufacturing a resonator provided in an embodiment of the present application;

[0059] Fig.30 This is a schematic structural diagram of a method for manufacturing a resonator provided in an embodiment of the present application after step S260 is completed;

[0060] Fig.31 A schematic diagram of the structure of a resonator provided in one embodiment of the present application;

[0061] Fig.32 Another structural schematic diagram of a resonator provided in an embodiment of the present application. DETAILED DESCRIPTION

[0062] In order to facilitate the understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present application are given in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thoroughly and comprehensively understood.

[0063] The following descriptions of the embodiments are with reference to the attached diagrams to illustrate specific embodiments that the present application can be used to implement. The serial numbers for the components herein, such as "first", "second", etc., are only used to distinguish the objects described and do not have any order or technical meaning. The "connection" and "coupling" mentioned in the present application, unless otherwise specified, include direct and indirect connections (couplings). The directional terms mentioned in the present application, such as "upper", "lower", "front", "back", "left", "right", "inside", "outside", "side", etc., are only with reference to the directions of the attached drawings. Therefore, the directional terms used are for better and clearer explanation and understanding of the present application, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present application.

[0064] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be fixedly connected, detachably connected, or integrally connected; it can be mechanically connected; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances. It should be noted that the terms "first", "second", etc. in the specification, claims, and drawings of this application are used to distinguish different objects, rather than to describe a specific order. In addition, the terms "include", "may include", "include", or "may include" used in this application indicate the existence of the corresponding functions, operations, elements, etc. disclosed, and do not limit one or more other functions, operations, elements, etc. In addition, the terms "include" or "include" indicate the existence of the corresponding features, numbers, steps, operations, elements, components, or combinations thereof disclosed in the specification, and do not exclude the existence or addition of one or more other features, numbers, steps, operations, elements, components, or combinations thereof, and are intended to cover non-exclusive inclusions.

[0065] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0066] The electronic device of the present application includes a radio frequency front-end module 200, and the electronic device of the present application receives and / or transmits signals through the radio frequency front-end module 200. Exemplarily, the electronic device includes at least one of a computer, a mobile phone, a tablet computer, a smart watch, and a navigator, etc., and the present application does not specifically limit this.

[0067] See also Figure 1 The structure diagram of the RF front-end module 200 provided in one embodiment of the present application is shown.

[0068] like Figure 1 As shown, the RF front-end module 200 includes a filter chip 201 and a second filter chip 202, and the pad 2021 on the second filter chip 202 is electrically connected to the first pad of the resonator 100. Figure 1 In the schematic diagram shown, the structure of the second filter chip 202 is different from the structure of the resonator 100 .

[0069] Among them, the second filter chip 202 includes ordinary surface acoustic wave filters (NSAW filters), temperature compensated surface acoustic wave filters (TCSAW filters) and filter devices formed by interconnecting them through a certain topology, including devices including interdigital transducers, which are not limited in this application.

[0070] exist Figure 1 In the illustrated example, there are two filter chips 201, wherein one filter chip 201 and the second filter chip 202 are mounted on the same side of the other filter chip 201. At this time, the other filter chip 201 and the second filter chip 202 mounted on the same side of the one filter chip 201 are connected in parallel.

[0071] Please see Figure 2 Another structural schematic diagram of the RF front-end module 200 provided in one embodiment of the present application is shown.

[0072] like Figure 2 As shown, the number of filter chips 201 is three, wherein two filter chips 201 are arranged on opposite sides of one filter chip 201. The RF front-end module 200 further includes a non-filter chip 203, wherein the non-filter chip 203 and the second filter chip 202 are arranged on opposite sides of one filter chip 201, wherein the pad of the non-filter chip 203 is electrically connected to the second pad of the filter chip 201, and the pad of the second filter chip 202 is electrically connected to the first pad of the filter chip 201.

[0073] In this embodiment, the non-filter chip 203 includes at least one of a power amplifier, a low noise amplifier, a radio frequency switch, a coupler, and a matching circuit.

[0074] For details, please refer to Figure 3 The figure shows a schematic diagram of the wiring structure of the RF front-end module 200 provided in one embodiment of the present application.

[0075] like Figure 3 As shown, the RF front-end module 200 also includes a signal terminal 204 and a switch 205. Among them, the non-filter chip 203 is an amplifier 206. The signal terminal 204 is used to receive an external signal or transmit a radio frequency signal. The switch 205 is arranged between the signal terminal 204 and the filter chip 201 to control the signal transmission between the signal terminal 204 and the filter chip 201. When the amplifier 206 is a low-noise amplifier, when the switch 205 is closed, the filter chip 201 is used to receive the external signal received by the signal terminal 204 and output a signal with a preset frequency.

[0076] The amplifier 206 is electrically connected to the filter chip 201 to amplify the signal processed by the filter chip 201 and output it to the subsequent structure. When the amplifier 206 is a power amplifier, the filter chip 201 is used to receive the RF signal amplified by the amplifier 206 when the switch 205 is closed, and filter the received RF signal, and then transmit the filtered RF signal to the signal terminal 204 through the switch 205. In one embodiment, the signal terminal 204 is an antenna.

[0077] In another embodiment, the RF front-end module 200 of the present application further includes a passive component, and the passive component is disposed on the filter chip 201. Figure 2 In the schematic diagram shown, the passive component can be used to replace the non-filter chip 203. In another embodiment, the passive component and the non-filter chip 203 can be simultaneously arranged on the filter chip 201, and this application does not specifically limit this. Among them, the passive component includes at least one of a resistor, an inductor, and a capacitor.

[0078] In one embodiment, the RF front-end module 200 further includes a multiplexer, and the multiplexer includes the resonator 100 .

[0079] In the embodiment of the present application, the filter chip 201 includes a resonator 100. Based on the description of the above embodiment, it can be seen that the resonator 100 of the present application can simultaneously realize the connection with multiple components based on its own structure. Compared with the prior art, the resonator 100 structure in the present application does not need to be separately provided with a circuit board or other adapter board, and can achieve the purpose of transfer or packaging, thereby effectively optimizing the device structure and preparation process.

[0080] Specifically, along the thickness direction of the resonator 100, when multiple components are arranged, each component can be arranged on the same side of the resonator 100 of the RF front-end module 200, or each component can be arranged on opposite sides of the resonator 100 corresponding to the RF front-end module 200. Correspondingly, each component is connected in series or in parallel through the internal structure of the resonator 100. In this way, the space in the thickness direction of the RF front-end module 200 is utilized, which is conducive to the miniaturization of the RF front-end module 200.

[0081] For details, see Figure 4 A schematic diagram of the working process of a method for manufacturing a resonator 100 provided in one embodiment of the present application is shown.

[0082] The manufacturing method of the resonator 100 of the present application specifically includes the following steps:

[0083] S100, providing a support layer 11;

[0084] Specifically, the support layer 11 is used to provide a support basis for the preparation of subsequent structures, thereby ensuring the structural strength of the resonator 100 of the present application and ensuring the integrity of the resonator 100 of the present application during use.

[0085] On the other hand, the support layer 11 can also adjust the performance of the resonator 100 of the present application based on its own material properties. In one embodiment, the material of the support layer 11 includes at least one of silicon, silicon carbide, silicon nitride and aluminum nitride. That is, the support layer 11 provided in step S100 of the present application can optimize the working performance of the resonator 100 of the present application based on the properties of the above materials.

[0086] Exemplarily, when the material of the support layer 11 is silicon, the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application has better electrical performance, and by directly preparing the resonator 100 on a silicon plate, and directly connecting or transferring with other functional devices through the silicon plate, the silicon plate can realize the function of the resonator 100 on the one hand, and realize the purpose of the transfer plate on the other hand, thereby simplifying the preparation process of the resonator 100 and improving the structure of the device.

[0087] S200, preparing at least one functional layer 12 and a piezoelectric layer 13 on the support layer 11, and etching to form a blind hole 21, wherein the depth of the blind hole 21 is greater than the sum of the thicknesses of the piezoelectric layer 13 and the functional layer 12, and less than the sum of the thicknesses of the piezoelectric layer 13, the functional layer 12 and the support layer 11;

[0088] For details, please refer to Figure 5 FIG. 1 is a schematic diagram of a structure of a method for manufacturing a resonator 100 provided in an embodiment of the present application after step S200 is completed. Figure 5As shown, the functional layer 12 can adjust the performance of the resonator 100 of the present application based on its own material properties. In one embodiment, the material of the functional layer 12 includes polycrystalline silicon material. Accordingly, the preparation of the functional layer 12 enables the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application to use the functional layer 12 to block the propagation of body waves during its operation, thereby reducing the energy loss caused by body waves. Thereby, the Q value of the resonator 100 of the present application is improved.

[0089] In another embodiment, the material of the functional layer 12 includes at least one of silicon dioxide, silicon oxynitride, tantalum oxide, and silicon dioxide doped with fluorine, carbon, boron, and hydrogen. Accordingly, the functional layer 12 is also used to adjust the temperature coefficient of frequency (TCF) of the resonator of the present application to reduce the influence of temperature on the frequency during the operation of the resonator 100 of the present application, thereby ensuring the sound wave quality of the resonator 100 of the present application.

[0090] In the embodiment of the present application, the preparation of the piezoelectric layer 13 enables the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application to realize the electroacoustic conversion function of the resonator 100 of the present application based on the piezoelectric effect of the piezoelectric layer 13. Thus, the signal processing function of the resonator 100 of the present application is guaranteed. Exemplarily, the material of the piezoelectric layer 13 includes at least one of lithium tantalate, lithium niobate and aluminum nitride.

[0091] That is, the preparation of the support layer 11, the functional layer 12 and the piezoelectric layer 13 in steps S100 and S200 of the present application ensures the signal processing function and performance of the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application.

[0092] In step S200 of the present application, the depth of the blind hole 21 is set to be greater than the sum of the thicknesses of the piezoelectric layer 13 and the functional layer 12, and less than the sum of the thicknesses of the piezoelectric layer 13, the functional layer 12 and the support layer 11, so that the bottom of the blind hole 21 is located in the support layer 11, so that the piezoelectric layer 13 is away from the surface of the functional layer 12, and can be connected with the structure of the support layer 11 through the blind hole 21. This facilitates the subsequent steps.

[0093] S300, depositing an insulating layer 31 and a metal layer 40 on the surface of the piezoelectric layer 13 and in the blind hole 21 in sequence, performing a thinning process after the deposition is completed, and preparing an IDT 511 and a first pad 61 on the surface of the piezoelectric layer 13, wherein the first pad 61 is respectively connected to the IDT 511 and the metal layer 40 in the blind hole 21;

[0094] For details, please refer to Figure 6 and Figure 7 ,in Figure 6This is a schematic structural diagram of the method for manufacturing the resonator 100 of the present application provided in one embodiment of the present application after step S300 is completed. Figure 7 FIG. 1 is a schematic diagram of a partially enlarged structure of a method for manufacturing a resonator 100 of the present application provided in an embodiment of the present application after step S300 is completed. Figure 6 and Figure 7 As shown, since some materials selected for the piezoelectric layer 13, the functional layer 12 and the supporting layer 11 may be conductive, an insulating layer 31 is first deposited in the blind hole 21, and then a metal layer 40 is deposited to achieve insulation between the metal layer 40 and the piezoelectric layer 13, the functional layer 12 and the supporting layer 11 respectively.

[0095] During the operation of the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application, the preparation of the insulating layer 31 prevents the electrical signal transmitted by the external circuit through the metal layer 40 from being transmitted to any one of the piezoelectric layer 13, the functional layer 12 and the support layer 11, thereby ensuring the working performance of the resonator 100 of the present application.

[0096] On the other hand, the provision of the insulating layer 31 can also protect the metal layer 40 to prevent the metal layer 40 from being damaged by external force or internal stress. This ensures the use function of the resonator 100 of the present application. At the same time, the insulating layer 31 can also support the metal layer 40 based on its own material properties, thereby improving the structural strength of the resonator 100 of the present application.

[0097] In one embodiment, the material of the insulating layer 31 includes silicon dioxide and silicon nitride. When the insulating layer 31 is deposited on the surface of the blind hole 21 and the piezoelectric layer 13, at least one method of plasma enhanced chemical vapor deposition (PECVD), thermal oxidation process, and high-density plasma chemical vapor deposition (HDPCVD) can be used to deposit the insulating layer 31 to ensure the deposition quality of the insulating layer 31 in the manufacturing method of the resonator 100 of the present application.

[0098] In the embodiment of the present application, the insulating layer 31 and the metal layer 40 are not only arranged in the blind hole 21, but also arranged on the surface of the piezoelectric layer 13 to ensure that the blind hole 21 is completely filled with the insulating layer 31 and the metal layer 40, and to ensure the insulating effect of the insulating layer 31 on the metal layer 40.

[0099] In step S300 of the present application, after the insulating layer 31 and the metal layer 40 are prepared, the insulating layer 31 and the metal layer 40 located on the surface of the piezoelectric layer 13 are removed by a thinning process to expose the surface of the piezoelectric layer 13, thereby facilitating the preparation of the interdigital transducer 511 and the first pad 61 in step S300 of the present application.

[0100] It is worth mentioning that during the thinning process, the manufacturing method of the resonator 100 of the present application can also thin the piezoelectric layer 13 through a thinning process to control the overall thickness of the piezoelectric layer 13, thereby avoiding the phenomenon that the piezoelectric layer 13 is too thick, resulting in a decrease in the electromechanical coupling coefficient between the piezoelectric layer 13 and the interdigital transducer 511.

[0101] At the same time, thinning the piezoelectric layer 13 through a thinning process is also beneficial to ensuring the roughness of the surface of the piezoelectric layer 13, and avoiding the effect of the electromechanical coupling coefficient between the piezoelectric layer 13 and the interdigital transducer 511 due to the excessive roughness of the surface of the piezoelectric layer 13. This ensures the electroacoustic conversion efficiency of the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application. In one embodiment, the thinning process in step S300 of the present application is a chemical mechanical polishing process (Chemical Mechanical Planning, CMP). Furthermore, the thinning process in step S300 of the present application can also be any other process that can thin the thickness of the film layer. That is, in the embodiment of the present application, any other process that can thin the thickness of the film layer is within the protection scope of the present application.

[0102] In step S300 of the present application, the interdigital transducer 511 and the first pad 61 are prepared so that the electrical signal transmitted to the interdigital transducer 511 via the first pad 61 can cooperate with the piezoelectric layer 13 to realize the electroacoustic conversion function of the resonator 100 of the present application. Specifically, due to the piezoelectric effect of the piezoelectric layer 13. When the first pad 61 is connected to the external circuit, the electrical signal will be transmitted to the interdigital transducer 511 via the first pad 61, and the interdigital transducer 511 will filter the electrical signal of a specific frequency and give it to the piezoelectric layer 13, and because the electrical signal is an alternating signal. It can be understood that the electrical signal transmitted by the interdigital transducer 511 to the piezoelectric layer 13 presents a periodic change, and correspondingly, the elastic deformation of the surface of the piezoelectric layer 13 also changes with the periodic change of the electrical signal, thereby forming a surface acoustic wave of a specific frequency released outward. The surface acoustic wave is used to realize the frequency selection filtering function and signal processing function of the resonator 100 of the present application.

[0103] S400, the support layer 11, the functional layer 12 and the piezoelectric layer 13 are synchronously transferred to the transfer substrate 71, the piezoelectric layer 13 is located between the support layer 11 and the transfer substrate 71, and then the surface of the support layer 11 is etched until the metal layer 40 in the blind hole 21 is exposed, and a second solder pad 62 that is conductive to the metal layer 40 is prepared on the surface of the support layer 11.

[0104] For details, please refer to Figure 8 FIG. 1 is a schematic diagram of a structure of a method for manufacturing a resonator 100 of the present application provided in one embodiment of the present application after step S400 is completed. Figure 8 As shown, in step S400 of the present application, the support layer 11, the functional layer 12 and the piezoelectric layer 13 are synchronously transferred to the transfer substrate 71 so that the surface of the support layer 11 away from the functional layer 12 is exposed, thereby making it easier to etch the surface of the support layer 11.

[0105] In step S400 of the present application, the metal layer 40 in the blind hole 21 is exposed by etching the surface of the support layer 11, and a second pad 62 that is conductive with the metal layer 40 is prepared on the surface of the support layer 11, so as to realize the conductive connection between the first pad 61 and the second pad 62 by using the metal layer 40. Therefore, when the resonator 100 of the present application is conductive with other structures, the external structures can be arranged on opposite sides of the resonator 100 of the present application along the thickness direction of the resonator 100 of the present application, and conductive connection is realized by the first pad 61 and the second pad 62 that are conductive with each other, so as to realize the switching function of the resonator 100 of the present application.

[0106] On the other hand, when the resonator 100 of the present application is electrically connected to other structures through the first pad 61 and the second pad 62, the resonator 100 of the present application and other devices are arranged along the thickness direction of the resonator 100. That is, the arrangement of the first pad 61, the second pad 62 and the metal layer 40 enables the resonator 100 of the present application to be connected to other structures in its thickness direction, so as to utilize the size of the resonator 100 of the present application in the thickness direction. In this way, the size of the resonator 100 of the present application along its own plane direction is reduced, which is conducive to the miniaturization of the resonator 100 of the present application.

[0107] In one embodiment, the hole depth of the blind hole 21 is greater than or equal to 20 μm, so as to ensure the depth of the blind hole 21 located in the support layer 11, and avoid the situation where the thickness of the support layer 11 of the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application is too thin. In this way, the structural strength of the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application is ensured.

[0108] Please see Fig. 9 Another schematic diagram of the working process of a method for manufacturing a resonator 100 provided in one embodiment of the present application is shown.

[0109] Step S100 “providing a support layer 11” includes the following steps:

[0110] S100a, selecting a support layer 11, wherein the thickness of the support layer 11 is greater than or equal to 300 μm and less than or equal to 800 μm.

[0111] Specifically, in the manufacturing method of the resonator 100 of the present application, when the thickness of the support layer 11 is too thin, on the one hand, the structural strength of the support layer 11 will be relatively low, which is not conducive to ensuring the structural strength of the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application. At the same time, since the support layer 11 is transferred during the manufacturing process of the resonator 100 of the present application, the support layer 11 is transferred. The excessively thin thickness of the support layer 11 leads to a low structural strength, which is not conducive to ensuring the structural stability of the support layer 11 during the transfer process.

[0112] On the other hand, since the manufacturing step S400 of the manufacturing method of the resonator 100 of the present application requires etching the support layer 11, if the thickness of the support layer 11 is too thin, it will break during the etching process, which is not conducive to the preparation of the resonator 100 of the present application.

[0113] If the thickness of the support layer 11 is too thick, on the one hand, the overall mass of the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application will be increased, thereby increasing the inertia of the vibration of the resonator 100, thereby affecting the response speed of the resonator 100 and reducing the sensitivity of the resonator 100.

[0114] Therefore, the manufacturing method of the resonator 100 of the present application selects a support layer 11 with a thickness between 300 μm and 800 μm so that the support layer 11 has sufficient structural strength, which is convenient for the manufacturing method of the resonator 100 of the present application. On the other hand, by limiting the thickness of the support layer 11, it is also helpful to ensure the structural strength of the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application, and ensure the response speed and sensitivity of the resonator 100.

[0115] In one embodiment, the thickness of the piezoelectric layer 13 is greater than or equal to 200 nm and less than or equal to 1000 nm. In one embodiment, the thickness of the piezoelectric layer 13 is greater than or equal to 200 nm and less than or equal to 500 nm. Exemplarily, the thickness of the piezoelectric layer 13 is one of 300 nm, 400 nm and 500 nm.

[0116] Among them, when the thickness of the piezoelectric layer 13 is too thick, the stress distribution in the piezoelectric layer 13 is uneven, which may lead to the inability to effectively transmit the electric field and surface acoustic waves, affecting the electromechanical coupling effect of the piezoelectric layer 13. When the thickness of the piezoelectric layer 13 is too thin, the piezoelectric layer 13 cannot effectively transmit surface acoustic waves, resulting in a decrease in energy conversion efficiency and a decrease in the electromechanical coupling coefficient. Correspondingly, when the piezoelectric layer 13 is too thick or too thin, the electromechanical coupling coefficient will decrease.

[0117] In the embodiment of the present application, the thickness of the piezoelectric layer 13 is set between 200 nm and 1000 nm, which is beneficial to ensure the electromechanical coupling coefficient of the piezoelectric layer 13 , thereby improving the sensitivity and response speed of the resonator 100 .

[0118] On the other hand, the thickness of the piezoelectric layer 13 will also affect the generation of the heterodyne mode. The resonator 100 of the present application limits the thickness range of the piezoelectric layer 13 to avoid the piezoelectric layer 13 being too thick or too thin to excite the heterodyne mode. This reduces the intensity of the heterodyne mode generated when the resonator 100 of the present application is working, which is conducive to improving the Q value and performance of the resonator 100 of the present application.

[0119] In one embodiment, the thickness of the functional layer 12 is greater than or equal to 200 nm and less than or equal to 3000 nm. In one embodiment, the thickness of the functional layer 12 is greater than or equal to 200 nm and less than or equal to 2000 nm. Exemplarily, the thickness of the functional layer 12 is one of 500 nm, 1000 nm and 1500 nm.

[0120] When the thickness of the functional layer 12 is too thick, the mass of the resonator 100 may be increased, thereby causing the natural frequency of the resonator 100 to change, which may cause the response speed and sensitivity of the resonator 100 to decrease. When the thickness of the functional layer 12 is too thin, the mechanical strength of the resonator 100 may be reduced. At the same time, excessive sensitivity may also cause the resonator 100 to have a large noise during operation.

[0121] In the embodiment of the present application, the thickness of the functional layer 12 is set between 200 nm and 3000 nm, which is beneficial to controlling the response speed and sensitivity of the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application, and can also ensure the structural strength of the resonator 100.

[0122] In one embodiment, along the thickness direction of the support layer 11, the diameter of the opening of the blind hole 21 is larger than the diameter of the bottom of the blind hole 21. Figure 5 As shown, the axis of the blind hole 21 coincides with the thickness direction of the support layer 11, so that the hole wall of the blind hole 21 is inclined relative to the hole bottom of the blind hole 21, and the angle between the hole wall of the blind hole 21 and the hole bottom of the blind hole 21 is α, wherein the angle α is an obtuse angle, which is conducive to depositing the insulating layer 31 and the metal layer 40 into the blind hole 21 in step S300, thereby ensuring the deposition effect of the insulating layer 31 at the hole wall of the blind hole 21. In addition, the performance of the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application is guaranteed.

[0123] Please see Fig.10 FIG. 1 is a schematic diagram of another working process of a method for manufacturing a resonator 100 provided in an embodiment of the present application.

[0124] In step S300, “the insulating layer 31 and the metal layer 40 are sequentially deposited on the surface of the piezoelectric layer 13 and in the blind hole 21, and a thinning process is performed after the deposition is completed, and an interdigital transducer 511 and a first pad 61 are prepared on the surface of the piezoelectric layer 13, and the first pad 61 is respectively connected to the interdigital transducer 511 and the metal layer 40 in the blind hole 21”, the following steps are also included:

[0125] S310, preparing an insulating layer 31 on the surface of the piezoelectric layer 13 and in the blind hole 21;

[0126] S320 , preparing a barrier layer 32 on the surface of the piezoelectric layer 13 and in the blind hole 21 , until the barrier layer 32 at least covers the insulating layer 31 in the blind hole 21 .

[0127] For details, please refer to Fig.11 and Fig.12 ,in Fig.11 This is a schematic diagram of the structure of the method for manufacturing the resonator 100 provided in one embodiment of the present application after step S320 is completed. Fig.12 It is a schematic diagram of a partially enlarged structure of the manufacturing method of the resonator 100 provided in one embodiment of the present application after step S320 is completed.

[0128] like Fig.11 and Fig.12 As shown, the barrier layer 32 is used to cover the insulating layer 31 located in the blind hole 21 and the insulating layer 31 located on the surface of the piezoelectric layer 13. It can be understood that in the manufacturing method of the resonator 100 of the present application, the manufacturing method of the resonator 100 of the present application covers the surface of the piezoelectric layer 13 with the barrier layer 32 to ensure that the barrier layer 32 can completely cover the insulating layer 31 in the blind hole 21.

[0129] During the manufacturing process of the resonator 100 of the present application, the barrier layer 32 is used to block the diffusion of the metal layer 40, preventing the metal layer 40 from diffusing into the insulating layer 31, thereby affecting the insulation of the insulating layer 31 to the metal layer 40. Thus, the use function of the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application is ensured.

[0130] In one embodiment, the material of the barrier layer 32 includes at least one of nickel, titanium, tantalum, titanium nitride, titanium-tungsten alloy and tantalum nitride. When preparing the barrier layer 32 on the surface of the blind hole 21 and the piezoelectric layer 13, at least one process selected from physical vapor deposition (PVD), atomic layer deposition (ALD) and chemical plating can be used to ensure the deposition quality of the barrier layer 32 in the manufacturing method of the resonator 100 of the present application.

[0131] In one embodiment, if Fig.10 As shown, in step S300, "the insulating layer 31 and the metal layer 40 are sequentially deposited on the surface of the piezoelectric layer 13 and in the blind hole 21, and a thinning process is performed after the deposition is completed, and an interdigital transducer 511 and a first pad 61 are prepared on the surface of the piezoelectric layer 13, and the first pad 61 is respectively connected to the interdigital transducer 511 and the metal layer 40 in the blind hole 21", the following steps are also included:

[0132] S330, preparing a seed layer 33 on the barrier layer 32, until the seed layer 33 at least covers the barrier layer 32 located in the blind hole 21;

[0133] S340 , preparing a metal layer 40 on the seed layer 33 .

[0134] For details, please refer to Figure 13-Figure 16 ,in Fig.13 This is a schematic diagram of the structure of the method for manufacturing the resonator 100 provided in one embodiment of the present application after step S330 is completed. Fig.14 FIG. 1 is a schematic diagram of a partially enlarged structure of a method for manufacturing a resonator 100 provided in an embodiment of the present application after step S330 is completed. Fig.15 This is a schematic diagram of the structure of the manufacturing method of the resonator 100 provided in one embodiment of the present application after step S340 is completed. Fig.16 It is a schematic diagram of a partially enlarged structure of the manufacturing method of the resonator 100 provided in one embodiment of the present application after step S340 is completed.

[0135] like Figure 13-Figure 16 As shown, the seed layer 33 is used to cover the barrier layer 32 located in the blind hole 21 and the barrier layer 32 located on the surface of the piezoelectric layer 13. It can be understood that in the manufacturing method of the resonator 100 of the present application, the manufacturing method of the resonator 100 of the present application covers the surface of the piezoelectric layer 13 with the seed layer 33 to ensure that the seed layer 33 can completely cover the barrier layer 32 in the blind hole 21.

[0136] In the manufacturing process of the manufacturing method of the resonator 100 of the present application, the provision of the seed layer 33 facilitates the preparation of the metal layer 40 in the blind hole 21 in the subsequent steps. Specifically, the seed layer 33 is used to provide a base for the preparation of the metal layer 40 to improve the preparation efficiency of the metal layer 40. Thus, the manufacturing efficiency of the manufacturing method of the resonator 100 of the present application is improved.

[0137] On the other hand, the provision of the seed layer 33 can also improve the deposition quality of the metal layer 40 and enhance the adhesion between the metal layer 40 and the barrier layer 32, thereby enhancing the connection strength of the metal layer 40 and ensuring the structural strength of the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application.

[0138] In one embodiment, the material of the seed layer 33 includes copper. When the seed layer 33 is prepared on the surface of the blind hole 21 and the piezoelectric layer 13, a sputtering coating process can be used to ensure the deposition quality of the barrier layer 32 in the manufacturing method of the resonator 100 of the present application.

[0139] In one embodiment, the material of the metal layer 40 includes at least one of tungsten, copper, copper-nickel alloy, copper-tungsten alloy and copper-tin alloy, and the metal layer 40 is prepared on the surface of the blind hole 21 and the piezoelectric layer 13 by electroplating process, and after the electroplating process, annealing and alloying are performed to achieve the preparation of the metal layer 40. In this way, the quality of the metal layer 40 in the manufacturing method of the resonator 100 of the present application is guaranteed.

[0140] In one embodiment, the hardness of the insulating layer 31 is greater than the hardness of the barrier layer 32, and the hardness of the barrier layer 32 is greater than the hardness of the seed layer 33. The insulating layer 31 with relatively large hardness is provided to utilize the self-strength of the insulating layer 31 to enhance the protective effect of the insulating layer 31 on the metal layer 40. At the same time, the insulating layer with relatively large hardness can also enhance the supporting performance of the film layer, thereby avoiding the situation in which the metal layer 40 is damaged due to movement during the manufacturing method of the resonator 100 of the present application and in subsequent use. Thus, the structural stability of the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application is ensured.

[0141] On the other hand, the insulating layer 31 with greater hardness generally has better thermal stability and heat resistance. The insulating layer 31 is sleeved on the outer edge of the metal layer 40, so that when the internal temperature of the resonator 100 rises due to operation, the insulating layer 31 can reduce the influence of thermal stress on the metal layer 40 based on its own thermal stability and heat resistance, further ensuring the protective effect of the insulating layer 31 on the metal layer 40. The structural stability of the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application is further ensured.

[0142] The barrier layer 32 with greater hardness has stronger compression and tensile resistance. In the preparation process of the manufacturing method of the resonator 100 of the present application, the barrier layer 32 with greater hardness can better block the diffusion of the metal layer 40. Thus, the working performance of the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application is guaranteed.

[0143] For the seed layer 33 , a seed layer 33 with too high hardness may make it difficult for the metal to form a good adhesion with the seed layer 33 during the process of depositing the metal layer 40 , thereby affecting the connection stability between the metal layer 40 and the seed layer 33 .

[0144] Therefore, by providing a seed layer 33 having a hardness lower than that of the barrier layer 32, it is possible to ensure the adhesion between the metal layer 40 and the seed layer 33 while improving the barrier effect of the barrier layer 32 on the diffusion of the metal layer 40. This ensures the structural stability of the resonator 100 manufactured by the manufacturing method of the resonator 100 of the present application.

[0145] Since the inner side of the insulating layer 31 is used to surround the barrier layer 32, the seed layer 33 and the metal layer 40, the outer side of the insulating layer 31 is used to adhere to the piezoelectric layer 13, the functional layer 12 and the support layer 11. During the operation of the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application, the piezoelectric layer 13, the functional layer 12 and the support layer 11 will vibrate under the action of the interdigital transducer 511. At the same time, the piezoelectric layer 13, the functional layer 12 and the support layer 11 will also generate thermal stress due to the increase of heat during the operation.

[0146] Therefore, an insulating layer 31 having a maximum hardness compared to the barrier layer 32 and the seed layer 33 is set, so that the insulating layer 31 can, based on its own structural strength, block the influence of thermal stress and vibration of the piezoelectric layer 13, the functional layer 12 and the support layer 11 on the metal layer 40 during operation, thereby further ensuring the structural stability of the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application.

[0147] In one embodiment, the thickness of the insulating layer 31 is greater than the thickness of the barrier layer 32, and greater than the thickness of the seed layer 33. In particular, the insulating layer 31 has a greater thickness than the seed layer 33 and the barrier layer 32 to ensure the structural strength of the insulating layer 31, thereby ensuring the insulating layer 31 has a blocking effect on the thermal stress and vibration of the piezoelectric layer 13, the functional layer 12 and the support layer 11 during operation, and further ensuring the structural stability of the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application.

[0148] For the barrier layer 32, the thickness of the barrier layer 32 only needs to ensure that the barrier layer 32 has a blocking effect on the diffusion effect of the metal layer 40. For the seed layer 33, the seed layer 33 only needs to provide an attachment surface for the deposition of the metal layer 40. An overly thick seed layer 33 may also cause uneven deposition of the metal layer 40, affecting the deposition quality of the metal layer 40.

[0149] Therefore, setting a barrier layer 32 and a seed layer 33 with a thickness less than that of the insulating layer 31 can further ensure the structural stability of the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application, under the premise that the barrier layer 32 blocks the diffusion of the metal layer 40 and the seed layer 33 provides a substrate for the deposition of the metal layer 40.

[0150] In one embodiment, if Fig.10As shown, in step S300, "the insulating layer 31 and the metal layer 40 are sequentially deposited on the surface of the piezoelectric layer 13 and in the blind hole 21, and a thinning process is performed after the deposition is completed, and an interdigital transducer 511 and a first pad 61 are prepared on the surface of the piezoelectric layer 13, and the first pad 61 is respectively connected to the interdigital transducer 511 and the metal layer 40 in the blind hole 21", the following steps are also included:

[0151] S350 , after the deposition is completed, a thinning process is performed to expose the surface of the piezoelectric layer 13 away from the functional layer 12 .

[0152] For details, please refer to Fig.17 The structure diagram of the manufacturing method of the resonator 100 provided in one embodiment of the present application is shown after step S350 is completed. In the process of depositing the insulating layer 31, the barrier layer 32, the seed layer 33 and the metal layer 40 into the blind hole 21, in order to ensure the deposition quality, it is necessary to deposit the insulating layer 31, the barrier layer 32, the seed layer 33 and the metal layer 40 on the surface of the piezoelectric layer 13.

[0153] In step S350 of the present application, after the deposition is completed, the insulating layer 31, the barrier layer 32, the seed layer 33 and the metal layer 40 deposited on the surface of the piezoelectric layer 13 are removed by a thinning process to expose the surface of the piezoelectric layer 13 facing away from the functional layer 12, so as to facilitate the subsequent steps of preparing the interdigital transducer 30 and the first pad 61 on the surface of the piezoelectric layer 13.

[0154] In one embodiment, if Fig.10 As shown, in step S300, "the insulating layer 31 and the metal layer 40 are sequentially deposited on the surface of the piezoelectric layer 13 and in the blind hole 21, and a thinning process is performed after the deposition is completed, and an interdigital transducer 511 and a first pad 61 are prepared on the surface of the piezoelectric layer 13, and the first pad 61 is respectively connected to the interdigital transducer 511 and the metal layer 40 in the blind hole 21", the following steps are also included:

[0155] S360, preparing a device layer 51 on the surface of the piezoelectric layer 13, wherein the device layer 51 includes each electrode finger 5111 of the interdigital transducer 511 and each bus bar 5112;

[0156] S370, preparing a passivation layer 52 on the surface of the device layer 51, and making the passivation layer 52 cover each electrode finger 5111;

[0157] S380, etching the passivation layer 52 until the surface of the piezoelectric layer 13 and the metal layer 40 are partially exposed, and preparing a first solder pad 61 on the surface of the exposed piezoelectric layer 13, the first solder pad 61 being respectively connected to the bus bar 5112 and the metal layer 40.

[0158] For details, please refer to Figure 18-Figure 22 ,in Fig.18This is a schematic diagram of the structure of the resonator 100 after the step S370 of the manufacturing method of the resonator 100 provided in one embodiment of the present application is completed. Fig.19 This is a schematic diagram of a partially enlarged structure of the resonator 100 after step S370 of the manufacturing method of the resonator 100 provided in an embodiment of the present application is completed. Fig. 20 1 is a schematic diagram of a top view of the structure of the resonator 100 after step S370 of the manufacturing method of the resonator 100 provided in an embodiment of the present application is completed. Fig.21 This is a structural diagram of the process of step S380 of the manufacturing method of the resonator 100 provided in one embodiment of the present application. Fig. 22 This is a schematic diagram of the structure of the resonator 100 after step S380 of the manufacturing method provided in one embodiment of the present application is completed. In order to facilitate the description of the structure of the interdigital transducer 511, Fig. 20 The metal layer 40 and the passivation layer 52 are omitted.

[0159] like Figure 18-Figure 22 As shown, the manufacturing method of the resonator 100 of the present application prepares a device layer 51 on the piezoelectric layer 13, and prepares a first pad 61 on the surface of the piezoelectric layer 13 exposed by etching, so as to achieve conduction between the bus bar 5112 and the first pad 61, thereby enabling the interdigital transducer 511 of the resonator 100 of the present application to be connected to the external circuit through the first pad 61.

[0160] In the embodiment of the present application, the arrangement of the electrode fingers 5111 and the bus bars 5112 of the interdigital transducer 511 ensures the acoustic-to-electric conversion function of the resonator 100 manufactured by the manufacturing method of the resonator 100 of the present application. Fig. 20 As shown, the interdigital transducer 511 includes two bus bars 5112 arranged in parallel and at intervals, and a plurality of electrode fingers 5111 arranged in parallel and at intervals. Among them, one bus bar 5112 of the two bus bars 5112 is used to receive external signals, and the other bus bar 5112 of the two bus bars 5112 is used to output signals. The plurality of electrode fingers 5111 are located between the two bus bars 5112. Some of the electrode fingers 5111 of the plurality of electrode fingers 5111 are connected to one bus bar 5112, and another part of the electrode fingers 5111 of the plurality of electrode fingers 5111 are connected to another bus bar 5112.

[0161] For ease of description, the bus bar 5112 for receiving external signals is defined as the first bus bar 5112a, and the bus bar 5112 for outputting signals is defined as the second bus bar 5112b. The electrode finger 5111 connected to the first bus bar 5112a is defined as the first electrode finger 5111a, and the electrode finger 5111 connected to the second bus bar 5112b is defined as the second electrode finger 5111b.

[0162] Specifically, the first electrode fingers 5111a and the second electrode fingers 5111b are alternately arranged along the first direction 001. The first electrode fingers 5111a and the second electrode fingers 5111b both extend along the second direction 002. Fig. 20 As shown, along the first direction 001, there is a second electrode finger 5111b between any two adjacent first electrode fingers 5111a, and there is a first electrode finger 5111a between any two adjacent second electrode fingers 5111b.

[0163] The first direction 001 is the extension direction of the bus bar 5112, that is, the first bus bar 5112a and the second bus bar 5112b both extend along the first direction 001. The second direction 002 intersects with the first direction 001. Exemplarily, the second direction 002 and the first direction 001 may be perpendicular to each other, so that each electrode finger 5111 has an angle of 90° with the bus bar 5112 connected thereto. Exemplarily, the second direction 002 may not be perpendicular to the first direction 001, so that each electrode finger 5111 has an angle greater than 90° with the bus bar connected thereto.

[0164] In an embodiment of the present application, when an external excitation signal is loaded on the IDT 511, the IDT 511 converts the electrical signal into a surface acoustic wave, which propagates along the surface of the piezoelectric layer 13 and is reflected by the reflection grating, and then converted into an electrical signal by the IDT 511 for output.

[0165] Among them, the surface acoustic wave is used to realize the frequency selection function and signal processing function of the resonator 100 of the present application. During the propagation of the surface acoustic wave, the main propagation direction of the surface acoustic wave is the first direction 001. However, in the actual process, due to the effects such as edge effect and sound wave diffraction, the propagation direction of the surface acoustic wave formed on the surface of the piezoelectric layer 13 may also be other directions. In one embodiment, the surface acoustic wave propagating in the other directions will be absorbed by the sound absorbing material (not shown in the figure).

[0166] It can be understood that the present application can be applied to high-Q-value piezoelectric film-type surface acoustic wave resonators (ML-SAW resonators) on insulators, conventional surface acoustic wave resonators (NSAW resonators), temperature-compensated surface acoustic wave resonators (TC-SAW resonators), and resonator devices formed by interconnecting them through a certain topology, including devices such as interdigital transducers, and the present application does not limit this.

[0167] In the embodiment of the present application, the passivation layer 52 is disposed on the relatively exposed surface of each electrode finger 5111 and covers each electrode finger 5111 to prevent corrosion caused by reaction between external water and oxygen and the electrode finger 5111, thereby achieving a protective function for the electrode finger 5111. On the other hand, the provision of the passivation layer 52 increases the mass load of the electrode finger 5111 on the piezoelectric layer 13, and the frequency adjustment of the interdigital transducer 511 can be achieved.

[0168] Since the passivation layer 52 is used to cover the surface of the piezoelectric layer 13 and the metal layer 40. In step S380, part of the passivation layer 52 on the surface of the piezoelectric layer 13 is etched to expose part of the piezoelectric layer 13 to reserve space for the preparation of the first pad 61. At the same time, the metal layer 40 is also exposed. In one embodiment, when etching part of the passivation layer 52, dry etching or wet etching combined with a photolithography process can be used, and photoresist protection is not used at the position where the first pad 61 needs to be prepared, thereby etching a window at the position of the first pad 61.

[0169] It is worth mentioning that in the process of step S380 of the present application, if Fig.18 As shown, the area of ​​the piezoelectric layer 13 formed after the etching of the passivation layer 52 is connected to the area where the metal layer 40 is located, and is connected to the area of ​​the piezoelectric layer 13 where the bus bar 5112 is located. In order to deposit the first pad 61 in this area, and make the first pad 61 conductive with the metal layer 40 and the bus bar 5112.

[0170] In one embodiment, the material of the first pad 61 includes at least one of aluminum, copper, copper-aluminum alloy, titanium, gold, and silver, so that the first pad 61 is connected to an external circuit.

[0171] In one embodiment, along the thickness direction of the support layer 11, the thickness of the first pad 61 is greater than or equal to 500 nm and less than or equal to 4000 nm, which, on the one hand, avoids the phenomenon that the first pad 61 is too thick and increases the parasitic capacitance of the resonator 100, thereby affecting the working efficiency of the resonator 100. On the other hand, it avoids the situation that the electrical contact is poor due to the first pad 61 being too thin. Therefore, under the premise of ensuring the conductive efficiency of the first pad 61, the performance of the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application is guaranteed.

[0172] In one embodiment, the material of the passivation layer 52 includes at least one of silicon dioxide, silicon nitride and silicon oxynitride to ensure the passivation layer 52 has a function of protecting the electrode fingers 5111 and a function of adjusting the frequency.

[0173] In one embodiment, along the thickness direction of the support layer 11, the thickness of the passivation layer 52 is greater than or equal to 20 nm and less than or equal to 100 nm, which, on the one hand, avoids the passivation layer 52 being too thick and affecting the electrical performance of the resonator 100. On the other hand, it avoids the passivation layer 52 being too thin and affecting the protection function of the electrode fingers 5111. Thus, under the premise of ensuring the protection function of the passivation layer 52, the performance of the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application is guaranteed.

[0174] In one embodiment, the material of the electrode finger 5111 includes at least one of aluminum, copper, copper-aluminum alloy, titanium, silver, cadmium and platinum to ensure the electroacoustic conversion function of the electrode finger 5111 and the piezoelectric layer 13.

[0175] In one embodiment, along the thickness direction of the support layer 11, the thickness of the electrode finger 5111 is greater than or equal to 50nm and less than or equal to 800nm, which avoids the increase of resistance and parasitic effects due to the excessive thickness of the electrode finger 5111, and avoids the phenomenon of reduced conductivity and mechanical strength due to the excessive thinness of the electrode finger 5111. Thus, under the premise of ensuring the conductivity of the electrode finger 5111, the resistance and power loss are reduced, and the performance of the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application is improved.

[0176] Please see Fig.23 FIG. 1 is a schematic diagram of another working process of a method for manufacturing a resonator 100 provided in an embodiment of the present application.

[0177] In step S400, “the support layer 11, the functional layer 12 and the piezoelectric layer 13 are synchronously transferred to the transfer substrate 71, the piezoelectric layer 13 is located between the support layer 11 and the transfer substrate 71, and the surface of the support layer 11 is etched until the metal layer 40 in the blind hole 21 is exposed, and a second pad 62 conductive with the metal layer 40 is prepared on the surface of the support layer 11.” also includes the following steps:

[0178] S420, coating a bonding adhesive 72 on the surface of the piezoelectric layer 13 until the bonding adhesive 72 covers the first pad 61 and the IDT 511;

[0179] S440, using a bonding process to adhere and fix the bonding adhesive 72 and the transfer substrate 71, wherein the bonding adhesive includes at least one of a heat-curing adhesive, an ultraviolet light-curing adhesive, a heat-decomposable adhesive, and a laser-decomposable adhesive.

[0180] For details, please refer to Fig.24 and Fig.25 ,in Fig.24 This is a schematic diagram of the structure of the manufacturing method of the resonator 100 provided in one embodiment of the present application after step S420 is completed. Fig.25Schematic diagram of the structure of the method for manufacturing the resonator 100 provided in one embodiment of the present application after step S440 is completed.

[0181] like Fig.24 and Fig.25 As shown, a bonding glue 72 that can completely cover the first pad 61 and the IDT 511 is coated on the surface of the piezoelectric layer 13 to prevent the IDT 511 and the first pad 61 from affecting the adhesion between the transfer substrate 71 and the bonding glue 72 when the piezoelectric layer 13 is fixed to the transfer substrate 71 through the bonding glue 72. At the same time, it also prevents the transfer substrate 71 from affecting the structural integrity of the IDT 511 and the first pad 61 when the bonding glue 72 is bonded.

[0182] In the embodiment of the present application, while the bonding process is used to achieve a fixed connection between the piezoelectric layer 13 and the transfer substrate 71, the bonding process also solidifies the bonding glue 72, so that the bonding glue 72 has a certain structural strength, thereby achieving protection for the first pad 61 and the interdigital transducer 511 during the transfer process.

[0183] like Fig.25 As shown, a transfer substrate 71 is provided to facilitate flipping the support layer 11, the functional layer 12 and the piezoelectric layer 13, and to expose the surface of the support layer 11 away from the functional layer 12, so as to facilitate etching of the support layer 11 in the subsequent steps. At this time, the transfer substrate 71 is used to support the support layer 11, the functional layer 12 and the piezoelectric layer 13.

[0184] In an embodiment of the present application, the bonding glue 72 adopts at least one of a heat-curing glue, an ultraviolet light-curing glue, a heat-decomposing glue and a laser-decomposing glue, so that in step S440, different bonding processes are set based on matching different bonding glues 72 to achieve the fixation of the piezoelectric layer 13 and the transfer substrate 71.

[0185] Exemplarily, when the bonding adhesive 72 adopts a heat-curing adhesive, during the bonding process, the bonding temperature is controlled to be greater than or equal to 40° C. and less than or equal to 200° C. The bonding pressure is controlled to be greater than or equal to 500 N and less than or equal to 8000 N. That is, when the bonding adhesive 72 adopts a heat-curing adhesive, by controlling the bonding temperature and the bonding pressure to the above range, it is beneficial to improve the curing efficiency of the bonding adhesive 72 and ensure the curing quality of the bonding adhesive 72.

[0186] In an embodiment of the present application, the bonding process of the bonding adhesive 72 can also match and set other parameters based on the particularity of the material of the bonding adhesive 72. For example, when the bonding adhesive 72 adopts ultraviolet light irradiation to cure the adhesive, during the bonding process, a light-transmitting transfer substrate 71 is used, and ultraviolet light irradiation can be increased, and the curing efficiency can be improved by controlling the intensity of the ultraviolet light to ensure the curing quality of the bonding adhesive 72. When the bonding adhesive 72 adopts a heat-decomposable adhesive, the temperature change needs to be controlled during the bonding process. When the bonding adhesive 72 adopts a laser-decomposable adhesive, the influence of the laser on the curing process needs to be avoided.

[0187] In other embodiments, the bonding adhesive 72 used in step S420 of the present application may also be other adhesive materials that can be temporarily bonded and debonded. Correspondingly, the bonding process used in step S440 of the present application may also be based on the material of the bonding adhesive 72 and matched with other corresponding bonding processes. The present application does not make any special limitation on this.

[0188] In one embodiment, the material of the transfer substrate 71 includes one of silicon, glass, silicon carbide and quartz to ensure the support function of the transfer substrate 71 to the piezoelectric layer 13 , the functional layer 12 and the support layer 11 .

[0189] In one embodiment, if Fig.23 As shown, step S400, "synchronously transferring the support layer 11, the functional layer 12 and the piezoelectric layer 13 to the transfer substrate 71, the piezoelectric layer 13 is located between the support layer 11 and the transfer substrate 71, and then etching the surface of the support layer 11 until the metal layer 40 in the blind hole 21 is exposed, and preparing a second pad 62 on the surface of the support layer 11 that is conductive to the metal layer 40." also includes the following steps:

[0190] S460, etching the surface of the support layer 11 until the metal layer 40 in the blind hole 21 is exposed;

[0191] S480 , preparing a second pad 62 on the surface of the support layer 11 , which is electrically connected to the metal layer 40 .

[0192] For details, please refer to Fig.26 The structure diagram of the manufacturing method of the resonator 100 provided in one embodiment of the present application after step S460 is completed is shown.

[0193] like Fig.26 As shown, based on step S440, the surface of the support layer 11 away from the functional layer 12 is exposed, and step S460 of the present application thins the support layer 11 by etching the surface of the support layer 11, and enables the metal layer 40 in the blind hole 21 to be exposed on the surface of the support layer 11. This facilitates the preparation of the second pad 62 in the subsequent steps.

[0194] In step S480 of the present application, the second pad 62 is prepared so that the resonator 100 of the present application can be electrically connected to other structures through the first pad 61 and the second pad 62, thereby realizing the switching function of the resonator 100 of the present application. On the other hand, the first pad 61 and the second pad 62 are arranged on two opposite surfaces of the resonator 100 of the present application, so that when the resonator 100 of the present application is electrically connected to other structures, the thickness direction of the resonator 100 of the present application is utilized. In this way, the size of the resonator 100 of the present application along its own plane direction is reduced, which is conducive to the miniaturization of the resonator 100 of the present application.

[0195] In one embodiment, step S460 of the present application may use etching or chemical mechanical polishing process to achieve thinning of the support layer 11, thereby ensuring the flatness of the surface of the support layer 11 away from the functional layer 12 in the manufacturing method of the resonator 100 of the present application.

[0196] In one embodiment, the material of the second pad 62 includes at least one of copper, tin, gold, silver, tin-lead alloy, tin-silver alloy, and tin-silver-copper alloy to ensure the conductivity of the second pad 62 .

[0197] Please see Fig. 27 FIG. 1 is a schematic flow chart of a method for manufacturing a resonator 100 provided in one embodiment of the present application.

[0198] like Fig. 27 As shown, after step S400, "synchronously transferring the support layer 11, the functional layer 12 and the piezoelectric layer 13 to the transfer substrate 71, the piezoelectric layer 13 is located between the support layer 11 and the transfer substrate 71, and then etching the surface of the support layer 11 until the metal layer 40 in the blind hole 21 is exposed, and preparing a second pad 62 conductive with the metal layer 40 on the surface of the support layer 11", the following steps are also included:

[0199] S500, removing the bonding glue 72 and the transfer substrate 71 by a debonding process, wherein the debonding process includes at least one of a blade-type debonding process, a chemical solvent immersion debonding process, a heating pretreatment debonding process, and a laser irradiation debonding process.

[0200] For details, please refer to Fig.28 The structure diagram of the manufacturing method of the resonator 100 provided in one embodiment of the present application after step S500 is completed is shown.

[0201] like Fig.28 As shown, after the second pad 62 is prepared, the bonding glue 72 and the transfer substrate 71 are removed by a debonding process to prepare a resonator 100. Thus, the manufacturing process of the resonator 100 of the manufacturing method of the present application is completed.

[0202] At the same time, based on step S420, the first pad 61 is covered with bonding glue 72, and the bonding glue 72 is removed through a debonding process to expose the first pad 61, so that an external device can be electrically connected to the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application through the first pad 61.

[0203] In the embodiment of the present application, the debonding process of the bonding glue 72 needs to be set to match the type of the bonding glue 72. Exemplarily, when the bonding glue 72 adopts a heat-curing type glue, a blade-type debonding process or a chemical solvent immersion debonding process can be used to remove the bonding glue 72. When the bonding glue 72 adopts an ultraviolet light irradiation curing type glue, a blade-type debonding process or a chemical solvent immersion debonding process can be used to remove the bonding glue 72. When the bonding glue 72 adopts a heat-decomposable type glue, a heat pretreatment debonding process can be used to remove the bonding glue 72. When the bonding glue 72 adopts a laser-decomposable type glue, a laser irradiation debonding process can be used to remove the bonding glue 72.

[0204] In other embodiments, the bonding adhesive 72 used in step S420 of the present application may also be other adhesive materials that can be temporarily bonded and debonded. Correspondingly, the bonding process used in step S500 of the present application may also be based on the material of the bonding adhesive 72 and matched with other corresponding debonding processes. The present application does not make any special limitation on this.

[0205] Please see Fig.29 Another schematic flow chart of a method for manufacturing a resonator 100 provided in one embodiment of the present application is shown.

[0206] like Fig.29 As shown, step S200, "preparing at least one functional layer 12 and a piezoelectric layer 13 on the support layer 11, and etching to form a blind hole 21, wherein the depth of the blind hole 21 is greater than the sum of the thicknesses of the piezoelectric layer 13 and the functional layer 12, and less than the sum of the thicknesses of the piezoelectric layer 13, the functional layer 12 and the support layer 11", comprises the following steps:

[0207] S230, preparing at least one functional layer 12 and a piezoelectric layer 13 on the support layer 11;

[0208] S260, first etching, etching the piezoelectric layer 13 to expose the surface of the functional layer 12;

[0209] S290, a second etching, etching the functional layer 12 and the film layer of the functional layer 12 away from the piezoelectric layer 13, and forming a blind hole 21, wherein the first etching and the second etching are performed using different etching processes.

[0210] For details, please refer to Fig.30The structure diagram of the manufacturing method of the resonator 100 provided by one embodiment of the present application is shown after step S260 is completed.

[0211] like Fig.30 As shown, the materials of the piezoelectric layer 13, the functional layer 12 and the support layer 11 are different. In the manufacturing method of the resonator 100 of the present application, only the piezoelectric layer 13 is etched in the first etching to ensure the accuracy of the pattern of the blind hole 21 formed on the piezoelectric layer 13. It can be understood that in the first etching process, the selection of the etching process is only based on the material preparation of the piezoelectric layer 13, and there is no need to consider the influence of the etching process of the first etching on the functional layer 12 and the support layer 11, thereby simplifying the etching difficulty and simplifying the manufacturing difficulty of the manufacturing method of the resonator 100 of the present application.

[0212] That is, the manufacturing method of the resonator 100 of the present application prepares the blind hole 21 by etching twice, which is convenient for controlling the relative position of the blind hole 21 on the one hand, and also reduces the difficulty of the etching process of etching the blind hole 21 on the other hand. This is conducive to ensuring the quality of the resonator 100 manufactured by the manufacturing method of the resonator 100 of the present application.

[0213] In one embodiment, the first etching adopts one or more of dry etching, wet etching, laser etching and chemical mechanical planarization (CMP). To ensure the relative position and etching quality of the blind hole 21 after the first etching is completed. Specifically, during the etching process, a method combining photolithography and etching processes can be used to prepare and form the blind hole 21. The part of the piezoelectric layer 13 not protected by the photoresist is removed, thereby forming a design pattern corresponding to the mask.

[0214] In one embodiment, the first etching is performed by dry etching. Since dry etching has high precision and causes less damage to the material, the first etching is performed by dry etching, which can ensure the accuracy of the relative position of the blind hole 21 and reduce the influence of etching on the piezoelectric layer 13.

[0215] In one embodiment, the second etching is performed by dry etching or wet etching to control the etching depth of the blind hole 21 .

[0216] In one embodiment, during the second etching process, at least the sidewall of the functional layer 12 corresponding to the blind hole 21 is processed so that the roughness of the sidewall of the functional layer 12 in the blind hole 21 is greater than the roughness of the sidewall of the piezoelectric layer 13 .

[0217] Since the sidewall with greater roughness can provide a larger contact area, and the larger contact area can increase the bonding strength. In the embodiment of the present application, the sidewall of the functional layer 12 corresponding to the blind hole 21 is processed to increase the roughness of the sidewall of the functional layer 12, thereby improving the bonding strength between the sidewall of the functional layer 12 corresponding to the blind hole 21 and the insulating layer 31 and the metal layer 40. In this way, the structural stability of the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application is ensured.

[0218] In one embodiment, during the second etching process, the side walls of the piezoelectric layer 13, the functional layer 12 and the supporting layer 11 corresponding to the blind hole 21 are processed to improve the roughness of the side walls of the piezoelectric layer 13, the functional layer 12 and the supporting layer 11, thereby improving the bonding strength between the side walls of the piezoelectric layer 13, the functional layer 12 and the supporting layer 11 and the insulating layer 31 and the metal layer 40, further ensuring the structural stability of the resonator 100 prepared by the manufacturing method of the resonator 100 of the present application.

[0219] Please see Fig.31 FIG. 1 is a schematic structural diagram of a resonator 100 provided in one embodiment of the present application.

[0220] like Fig.31 As shown, the resonator 100 of the present application includes a substrate 10, an IDT 511, a conductive member 80, a first pad 61, and a second pad 62. The substrate 10 includes a stacked support layer 11, at least one functional layer 12, and a piezoelectric layer 13. Along the thickness direction of the substrate 10, the first pad 61 and the IDT 511 are located on the surface of the piezoelectric layer 13, the first pad 61 is connected to the IDT 511, and the second pad 62 is located on the surface of the support layer 11. The substrate 10 is provided with a through hole 22, and the conductive member 80 is received in the through hole 22. Along the thickness direction of the substrate 10, the opposite ends of the conductive member 80 are respectively connected to the first pad 61 and the second pad 62.

[0221] In the embodiment of the present application, the support layer 11 is used to support the functional layer 12, the piezoelectric layer 13 and the interdigital transducer 511. The support layer 11 is also used to ensure the structural strength of the resonator 100 of the present application and the integrity of the resonator 100 of the present application during use. At the same time, since the support layer 11 can also adjust the performance of the resonator 100 of the present application based on its own material properties, the working performance of the resonator 100 of the present application is optimized.

[0222] The functional layer 12 can adjust the performance of the resonator 100 of the present application based on its own material properties. Specifically, the functional layer 12 can block the propagation of body waves during the operation of the resonator 100 of the present application, thereby reducing the energy loss caused by the body waves. This improves the Q value of the resonator 100 of the present application. On the other hand, the functional layer 12 is also used to adjust the frequency temperature coefficient of the resonator of the present application to reduce the influence of temperature on the frequency during the operation of the resonator 100 of the present application, thereby ensuring the sound wave quality of the resonator 100 of the present application.

[0223] The piezoelectric layer 13 is used to cooperate with the interdigital transducer 511 to realize the electroacoustic conversion function of the resonator 100 of the present application. The first pad 61 is connected between the interdigital transducer 511 and the second pad 62, and the first pad 61 and the second pad 62 are both used to conduct with the external circuit. It can be understood that due to the piezoelectric effect of the piezoelectric layer 13. When the first pad 61 or the second pad 62 is connected to the external circuit, the electrical signal will be transmitted to the interdigital transducer 511 via the first pad 61, and the interdigital transducer 511 will filter the electrical signal of a specific frequency to the piezoelectric layer 13, and because the electrical signal is an alternating signal. It can be understood that the electrical signal transmitted by the interdigital transducer 511 to the piezoelectric layer 13 presents a periodic change, and correspondingly, the elastic deformation of the surface of the piezoelectric layer 13 also changes with the periodic change of the electrical signal, thereby forming a surface acoustic wave of a specific frequency released outward. The surface acoustic wave is used to realize the frequency selection filtering function and signal processing function of the resonator 100 of the present application.

[0224] In the embodiment of the present application, when the resonator 100 of the present application is connected to other structures, the external structure can be arranged on opposite sides of the resonator 100 of the present application along the thickness direction of the resonator 100 of the present application, and the connection can be achieved through the first pad 61 and the second pad 62 that are connected to each other, thereby realizing the switching function of the resonator 100 of the present application.

[0225] On the other hand, when the resonator 100 of the present application is electrically connected to other structures through the first pad 61 and the second pad 62, the resonator 100 of the present application and other structures are arranged along the thickness direction of the resonator 100. That is, the arrangement of the first pad 61, the second pad 62 and the conductive member 80 enables the resonator 100 of the present application to be conductive with other structures in its own thickness direction, so as to utilize the size of the resonator 100 of the present application in the thickness direction. This reduces the size of the resonator 100 of the present application along its own plane direction, which is conducive to the miniaturization of the resonator 100 of the present application.

[0226] Please see Fig.32 Another schematic structural diagram of a resonator 100 provided in one embodiment of the present application is shown.

[0227] like Fig.32As shown, the functional layer 12 has two layers, and the two functional layers 12 include a first functional layer 121 and a second functional layer 122. The material of the first functional layer 121 is different from the material of the second functional layer 122. The first functional layer 121 is bonded to the support layer 11, and the second functional layer 122 is bonded to the piezoelectric layer 13; wherein the thickness of the first functional layer 121 is greater than or equal to 200nm and less than or equal to 2000nm; and / or the thickness of the second functional layer 122 is greater than or equal to 200nm and less than or equal to 1000nm.

[0228] In the embodiment of the present application, the first functional layer 121 can block the propagation of body waves during the operation of the resonator 100 of the present application, thereby reducing the energy loss caused by the body waves. This improves the Q value of the resonator 100 of the present application. The second functional layer 122 is used to adjust the frequency temperature coefficient of the resonator 100 of the present application to reduce the influence of temperature on the frequency during the operation of the resonator 100 of the present application, thereby ensuring the sound wave quality of the resonator 100 of the present application.

[0229] Among them, for the first functional layer 121, when the first functional layer 121 is too thick, the electromechanical coupling efficiency between the first functional layer 121 and the piezoelectric layer 13 will be reduced, thereby reducing the response speed and sensitivity of the resonator 100 of the present application. When the first functional layer 121 is too thin, the blocking effect of the first functional layer 121 on the body wave is weakened, thereby affecting the stability and Q value of the resonator 100 of the present application.

[0230] Therefore, limiting the thickness of the first functional layer 121 to between 200 nm and 2000 nm can ensure the response speed and sensitivity of the resonator 100 of the present application while ensuring the blocking effect of the first functional layer 121 on body waves, thereby ensuring the performance stability and Q value of the resonator 100 of the present application.

[0231] For the second functional layer 122, when the second functional layer 122 is too thick, the second functional layer 122 may be less sensitive to temperature, thereby affecting the response speed of the second functional layer 122 to temperature changes. When the second functional layer 122 is too thin, the second functional layer 122 may not be able to provide sufficient temperature compensation, thereby limiting the ability of the second functional layer 122 to adjust the frequency temperature coefficient, thereby affecting the accuracy and reliability of the resonator 100 of the present application.

[0232] Therefore, the thickness of the second functional layer 122 is limited to between 200nm and 1000nm, which can ensure the response speed of the second functional layer 122 to temperature changes while ensuring the temperature compensation capability of the second functional layer 122 and the ability of the second functional layer 122 to adjust the frequency temperature coefficient, thereby ensuring the accuracy and reliability of the resonator 100 of the present application.

[0233] In one embodiment, the material of the first functional layer 121 includes polysilicon material to achieve the blocking function of the resonator 100 of the present application to the bulk wave, thereby improving the Q value of the resonator 100 of the present application.

[0234] In one embodiment, the material of the second functional layer 122 includes at least one of silicon dioxide, silicon oxynitride, tantalum oxide, and silicon dioxide doped with fluorine, carbon, boron, and hydrogen, so as to realize the frequency temperature coefficient adjustment function of the resonator 100 of the present application, thereby ensuring the sound wave quality of the resonator 100 of the present application.

[0235] It should be understood that the terms "first", "second", etc. are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of the embodiments of the present application, "plurality" means two or more, unless otherwise clearly and specifically defined.

[0236] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiments or examples are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0237] It should be understood that the application of the present application is not limited to the above examples. For ordinary technicians in the field, improvements or changes can be made according to the above description, and all these improvements and changes should fall within the scope of protection of the claims attached to this application. Ordinary technicians in the field can understand that all or part of the processes of the above embodiments are implemented, and equivalent changes made according to the claims of the present invention still fall within the scope of the present invention.

Claims

1. A method for manufacturing a resonator, characterized in that: The steps include: providing a support layer; Preparing at least one functional layer and a piezoelectric layer on the support layer, and etching to form a blind hole, wherein the depth of the blind hole is greater than the sum of the thicknesses of the piezoelectric layer and the functional layer, and less than the sum of the thicknesses of the piezoelectric layer, the functional layer and the support layer; An insulating layer and a metal layer are sequentially deposited on the surface of the piezoelectric layer and in the blind hole, and a thinning process is performed after the deposition is completed, and an interdigital transducer and a first pad are prepared on the surface of the piezoelectric layer, and the first pad is respectively connected to the interdigital transducer and the metal layer in the blind hole; The supporting layer, the functional layer and the piezoelectric layer are synchronously transferred to a transfer substrate, wherein the piezoelectric layer is located between the supporting layer and the transfer substrate. The surface of the supporting layer is then etched until the metal layer in the blind hole is exposed, and a second pad conductive to the metal layer is prepared on the surface of the supporting layer.

2. The method for manufacturing a resonator according to claim 1, characterized in that: The step of "providing a support layer" includes: A support layer is selected, and the thickness of the support layer is greater than or equal to 300 μm and less than or equal to 800 μm.

3. The method for manufacturing a resonator according to claim 1, characterized in that: The thickness of the piezoelectric layer is greater than or equal to 200 nm and less than or equal to 1000 nm; and / or the thickness of the functional layer is greater than or equal to 200 nm and less than or equal to 3000 nm.

4. The method for manufacturing a resonator according to claim 1, characterized in that: Along the thickness direction of the support layer, the diameter of the opening of the blind hole is greater than the diameter of the bottom of the blind hole.

5. The method for manufacturing a resonator according to any one of claims 1 to 4, characterized in that: The step of "preparing a barrier layer on the surface of the piezoelectric layer and in the blind hole" further includes: A barrier layer is prepared on the surface of the piezoelectric layer and in the blind hole, until the barrier layer at least covers the insulating layer in the blind hole.

6. The method for manufacturing a resonator according to claim 5, characterized in that: The step of "preparing a barrier layer on the surface of the piezoelectric layer and in the blind hole" also includes: A seed layer is formed on the barrier layer until the seed layer at least covers the barrier layer in the blind hole.

7. The method for manufacturing a resonator according to any one of claims 1 to 4, characterized in that: The step of "preparing an interdigital transducer and a first pad on the surface of the piezoelectric layer" also includes: Prepare a device layer on the surface of the piezoelectric layer, wherein the device layer includes each electrode finger and each bus bar of the interdigital transducer; Preparing a passivation layer on the surface of the device layer, and making the passivation layer cover each of the electrode fingers; The passivation layer is etched until a surface portion of the piezoelectric layer and the metal layer are exposed, and the first pad is prepared on the surface of the exposed piezoelectric layer, and the first pad is respectively connected to the bus bar and the metal layer.

8. The method for manufacturing a resonator according to any one of claims 1 to 4, characterized in that: The step of "synchronously transferring the support layer, the functional layer and the piezoelectric layer to a transfer substrate" comprises: Coating bonding glue on the surface of the piezoelectric layer until the bonding glue covers the first pad and the interdigital transducer; The bonding adhesive and the transfer substrate are bonded and fixed by a bonding process, wherein the bonding adhesive comprises at least one of a heat-curable adhesive, an ultraviolet light-curable adhesive, a heat-decomposable adhesive and a laser-decomposable adhesive.

9. The method for manufacturing a resonator according to claim 8, characterized in that: After the step of "preparing a second pad on the surface of the support layer that is conductive with the metal layer", the method further includes: The bonding glue and the transfer substrate are removed by a debonding process, wherein the debonding process includes at least one of a blade-type debonding process, a chemical solvent immersion debonding process, a heating pretreatment debonding process, and a laser irradiation debonding process.

10. The method for manufacturing a resonator according to any one of claims 1 to 4, characterized in that: The step of "etching to form a blind hole" also includes: A first etching step is to etch the piezoelectric layer to expose the surface of the functional layer; The second etching is to etch the functional layer and the film layer of the functional layer away from the piezoelectric layer to form the blind hole, wherein the first etching and the second etching are performed using different etching processes.

11. The method for manufacturing a resonator according to claim 10, characterized in that: During the second etching process, at least the side wall of the functional layer corresponding to the blind hole is processed so that the roughness of the side wall of the functional layer in the blind hole is greater than the roughness of the side wall of the piezoelectric layer.

12. A resonator, characterized in that: The invention comprises a substrate, an IDT, a conductive member, a first pad and a second pad, wherein the substrate comprises a stacked support layer, at least one functional layer and a piezoelectric layer, and along the thickness direction of the substrate, the first pad and the IDT are located on the surface of the piezoelectric layer, the first pad is conductively connected to the IDT, and the second pad is located on the surface of the support layer; The substrate is provided with a through hole, the conductive member is received in the through hole, and along the thickness direction of the substrate, opposite ends of the conductive member are respectively connected to the first pad and the second pad.

13. The resonator according to claim 12, characterized in that The functional layer has two layers, and the two functional layers include a first functional layer and a second functional layer. The material of the first functional layer is different from that of the second functional layer. The first functional layer is bonded to the support layer, and the second functional layer is bonded to the piezoelectric layer. The thickness of the first functional layer is greater than or equal to 200 nm and less than or equal to 2000 nm; and / or the thickness of the second functional layer is greater than or equal to 200 nm and less than or equal to 1000 nm.

14. A radio frequency front-end module, characterized in that: The filter chip comprises a resonator manufactured by the method for manufacturing a resonator according to any one of claims 1 to 11; or, comprises a resonator according to claim 12 or 13.

15. The RF front-end module according to claim 14, characterized in that: The RF front-end module also includes a second filter chip, the pads on the second filter chip are electrically connected to the first pads on the resonator, and the preparation method of the second filter chip is different from the preparation method of the resonator.

16. The radio frequency front-end module according to claim 15, characterized in that: The RF front-end module further includes at least one of a passive component and a non-filter chip, wherein the passive component and the non-filter chip are at least arranged on one side of the filter chip, the pads on the passive component and the non-filter chip are electrically connected to the first pad or the second pad, and the passive component includes at least one of a resistor, an inductor and a capacitor; The non-filter chip includes at least one of a power amplifier, a low noise amplifier, a radio frequency switch, a coupler, a matching circuit, and the like.

17. An electronic device, characterized in that: Comprising a radio frequency front-end module as described in any one of claims 14-16.

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