A dual-temperature compensation structure resonator and filter and a method of manufacturing the same

Abstract

The application belongs to the technical field of resonator and filter processing, and discloses a resonator and filter with a double-temperature compensation structure and a preparation method thereof, the preparation method comprising: growing a peeling layer, a piezoelectric layer and a patterned silicon layer on the surfaces of two silicon wafers in sequence, bonding the patterned silicon layers of the two silicon wafers through an oxygen diffusion method of normal-temperature non-metal bonding to obtain a first bonding substrate with a silicon dioxide temperature compensation layer, peeling off any silicon wafer and the corresponding peeling layer to obtain a second bonding substrate, bonding a third silicon wafer etched with a cavity structure with the second bonding substrate to obtain a third bonding substrate with a double-temperature compensation structure, peeling off another silicon wafer and the corresponding peeling layer, and growing a top electrode on the surface of the piezoelectric layer to obtain a resonator with a double-temperature compensation structure; and the oxygen diffusion method of normal-temperature non-metal bonding is used to bond the silicon dioxide temperature compensation layer, thereby improving the working performance of the resonator.

Description

Technical Field

[0001] This application relates to the technical field of resonator and filter fabrication, and more specifically, to a resonator and filter with a dual temperature-compensated structure and a method for fabricating the same. Background Technology

[0002] With the rapid development of artificial intelligence, big data processing and real-time interactive communication technologies have ushered in new development opportunities. To meet the communication demands of high data throughput, low latency, high speed, and wide coverage, next-generation communication technologies have placed more stringent requirements on the high-frequency, broadband, and high-power capacity performance of filters. Among them, bulk acoustic wave filters, due to their steep sag at high frequencies, high suppression, and low insertion loss performance, have become one of the important directions for the future development of communication technologies.

[0003] However, as the operating frequency of filters continues to increase, the thickness of each functional film layer decreases sharply. This leads to a significant increase in internal defects and electrical losses in the thin film, which in turn exacerbates the self-heating phenomenon of the filter. As a typical negative temperature coefficient material, the piezoelectric thin film of a bulk acoustic wave filter exhibits significant frequency shift under self-heating effects, severely impacting the device's performance and power capacity. Furthermore, in some special application environments, even higher requirements are placed on the temperature stability of the filter.

[0004] To address the aforementioned temperature offset issue, existing technologies typically introduce silicon dioxide, a material with a positive temperature coefficient, as a temperature compensation layer. However, the acoustic impedance of silicon dioxide is much lower than that of piezoelectric materials. Introducing silicon dioxide into a sandwich structure leads to significant interfacial acoustic scattering within the structure, resulting in increased transverse acoustic leakage and consequently affecting the overall filter performance. More importantly, the amorphous silicon dioxide temperature compensation layer prepared by conventional deposition methods exhibits a high density of defects on its surface. These defects accumulate during the subsequent growth of the piezoelectric layer, causing a sharp decline in the crystal quality of the piezoelectric material and ultimately significantly reducing the filter's performance. Therefore, effectively and with high quality, introducing a temperature compensation layer, especially a patterned temperature compensation layer, to achieve high-performance, high-stability thin-film bulk acoustic resonators and filters is a pressing technical challenge that needs to be addressed.

[0005] Therefore, in order to solve the technical problem that the high defect density and reduced crystal quality of amorphous silicon dioxide temperature-compensated layers prepared by traditional deposition methods lead to a significant reduction in the performance of resonators and filters, there is an urgent need for a resonator and filter with a dual temperature-compensated structure and its fabrication method. Summary of the Invention

[0006] The purpose of this application is to provide a resonator and filter with a dual temperature compensation structure and a method for fabricating the same. A high-quality silicon dioxide temperature compensation layer is bonded by a room-temperature non-metallic bonding oxygen diffusion method to prepare a resonator with a dual temperature compensation structure. This solves the problem that the high defect density and reduced crystal quality of amorphous silicon dioxide temperature compensation layers prepared by traditional deposition methods lead to a significant reduction in the performance of the resonator and filter. The introduction of a room-temperature non-metallic bonding oxygen diffusion method forms a high-quality silicon dioxide temperature compensation layer, thereby improving the working performance of the resonator.

[0007] In a first aspect, this application provides a method for fabricating a resonator with a dual temperature-compensated structure, comprising:

[0008] A release layer, a piezoelectric layer, and a patterned silicon layer are sequentially grown on the surfaces of the first silicon wafer and the second silicon wafer, respectively.

[0009] By using a room-temperature non-metallic bonding oxygen diffusion method, the patterned silicon layers of the first silicon wafer and the second silicon wafer are bonded to form a silicon dioxide temperature compensation layer, resulting in a first bonded substrate with a silicon dioxide temperature compensation layer disposed at the center.

[0010] The first silicon wafer of the first bonding substrate and its corresponding release layer are peeled off to obtain a second bonding substrate with one end exposed to the piezoelectric layer.

[0011] By using a room-temperature non-metallic bonding oxygen diffusion method, a third silicon wafer with an etched cavity structure is bonded to one end of the exposed piezoelectric layer of the second bonding substrate to obtain a third bonding substrate with a dual temperature compensation structure.

[0012] After peeling off the second silicon wafer and its corresponding release layer at the end away from the cavity structure, a top electrode is grown on the surface of the piezoelectric layer at the end away from the cavity structure to obtain a resonator with a dual temperature compensation structure.

[0013] The method for fabricating a dual-temperature-compensated resonator provided in this application can prepare a dual-temperature-compensated resonator by bonding a high-quality silicon dioxide temperature-compensated layer using a room-temperature non-metallic bonding oxygen diffusion method. This method solves the problem of high defect density and reduced crystal quality in amorphous silicon dioxide temperature-compensated layers prepared by traditional deposition methods, which leads to a significant reduction in the performance of resonators and filters. The method introduces a room-temperature non-metallic bonding oxygen diffusion method to form a high-quality silicon dioxide temperature-compensated layer, thereby improving the working performance of the resonator.

[0014] Optionally, a release layer, a piezoelectric layer, and a patterned silicon layer are sequentially grown on the surfaces of the first silicon wafer and the second silicon wafer, respectively, including:

[0015] The first silicon wafer and the second silicon wafer were cleaned sequentially with acetone and hydrofluoric acid, respectively, to obtain the cleaned first silicon wafer and the cleaned second silicon wafer.

[0016] Using physical vapor deposition and chemical vapor deposition, a release layer, a piezoelectric layer, and a patterned silicon layer are sequentially grown on the surfaces of the first and second cleaned silicon wafers, respectively.

[0017] Optionally, the release layer is made of one of aluminum gallium nitride, barium chloride, calcium fluoride, graphene, and boron nitride.

[0018] Optionally, a third silicon wafer with an etched cavity structure is bonded to one end of the exposed piezoelectric layer of the second bonding substrate using an oxygen diffusion method with room temperature non-metallic bonding, to obtain a third bonding substrate with a dual temperature-compensated structure, comprising:

[0019] The third silicon wafer is etched using etching technology to obtain a third silicon wafer with an etched cavity structure.

[0020] A bottom electrode and a silicon layer structure are grown on one end of the exposed piezoelectric layer of the second bonding substrate;

[0021] By using an oxygen diffusion method with room temperature non-metallic bonding, the third silicon wafer with the etched cavity structure is bonded to the silicon layer structure to obtain a third bonded substrate with a dual temperature compensation structure.

[0022] The method for fabricating a resonator with a dual temperature-compensated structure provided in this application can fabricate a resonator with a dual temperature-compensated structure. Through the formation process of the cavity structure and the second temperature-compensating layer, and through precise etching and bonding techniques, the bottom cavity of the resonator is constructed, and a silicon layer structure is further introduced as a temperature-compensating layer, thereby forming a complete dual temperature-compensating structure, which effectively improves the temperature stability and acoustic performance of the device.

[0023] Secondly, a resonator with a dual temperature-compensated structure is prepared by applying the above-described method for preparing a resonator with a dual temperature-compensated structure, comprising a silicon substrate, a first temperature-compensated layer, a bottom electrode, a piezoelectric layer, and a top electrode connected sequentially from bottom to top.

[0024] The silicon substrate has a protruding edge, forming a protrusion. The silicon substrate and the edge of the first temperature compensation layer are connected through the protrusion, forming a cavity structure between the silicon substrate and the first temperature compensation layer. A second temperature compensation layer is disposed in the piezoelectric layer. The upper surface of the first temperature compensation layer is connected to the bottom electrode and the piezoelectric layer, respectively.

[0025] This resonator with a dual temperature compensation structure is fabricated by bonding a high-quality silicon dioxide temperature compensation layer using a room-temperature non-metallic bonding oxygen diffusion method. This method addresses the problem of high defect density and reduced crystal quality in amorphous silicon dioxide temperature compensation layers prepared by traditional deposition methods, which leads to a significant decrease in the performance of resonators and filters. By introducing a room-temperature non-metallic bonding oxygen diffusion method to form a high-quality silicon dioxide temperature compensation layer, the operating performance of the resonator is improved.

[0026] Optionally, the piezoelectric layer is made of any one or more of aluminum nitride, scandium aluminum nitride, and aluminum nitride.

[0027] Optionally, the bottom electrode is made of any one or more of gold, silver, ruthenium, tungsten, molybdenum, iridium, aluminum, platinum, niobium, and hafnium.

[0028] Optionally, the top electrode is made of any one or more of gold, silver, ruthenium, tungsten, molybdenum, iridium, aluminum, platinum, niobium, and hafnium.

[0029] Optionally, the bottom electrode and the top electrode have the same thickness.

[0030] Thirdly, a filter with a dual-temperature-compensated structure, including the resonator with the dual-temperature-compensated structure described above.

[0031] Beneficial effects: This application provides a resonator and filter with a dual temperature compensation structure and a method for fabricating the same. By using a room-temperature non-metallic bonding oxygen diffusion method to bond a high-quality silicon dioxide temperature compensation layer, a resonator with a dual temperature compensation structure is prepared. This solves the problem that the high defect density and reduced crystal quality of amorphous silicon dioxide temperature compensation layers prepared by traditional deposition methods lead to a significant reduction in the performance of the resonator and filter. The introduction of a room-temperature non-metallic bonding oxygen diffusion method to form a high-quality silicon dioxide temperature compensation layer improves the working performance of the resonator and filter. Attached Figure Description

[0032] Figure 1 A flowchart illustrating the fabrication method of a resonator with a dual temperature-compensated structure provided in this application embodiment.

[0033] Figure 2 This is a schematic diagram of the structure of a resonator with a dual temperature compensation structure provided in an embodiment of this application.

[0034] Labeling explanations: 101, silicon substrate; 102, cavity structure; 103, first temperature compensation layer; 104, bottom electrode; 105, second temperature compensation layer; 106, piezoelectric layer; 107, top electrode. Detailed Implementation

[0035] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0036] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this application, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0037] Please refer to Figure 1 , Figure 1 A flowchart illustrating a method for fabricating a resonator with a dual temperature-compensated structure, provided in this application embodiment, is included for fabricating such a resonator.

[0038] Step S101: A release layer, a piezoelectric layer, and a patterned silicon layer are sequentially grown on the surfaces of the first silicon wafer and the second silicon wafer, respectively.

[0039] Step S102: The patterned silicon layers of the first silicon wafer and the second silicon wafer are bonded by oxygen diffusion method of room temperature non-metallic bonding to form a silicon dioxide temperature compensation layer, and a first bonded substrate with a silicon dioxide temperature compensation layer disposed in the center is obtained.

[0040] Step S103: The first silicon wafer of the first bonding substrate and its corresponding release layer are peeled off to obtain a second bonding substrate with one end exposed to the piezoelectric layer.

[0041] Step S104: Using a room temperature non-metallic bonding oxygen diffusion method, the third silicon wafer with an etched cavity structure is bonded to one end of the exposed piezoelectric layer of the second bonding substrate to obtain a third bonding substrate with a dual temperature compensation structure.

[0042] In step S105, after peeling off the second silicon wafer and its corresponding release layer at the end away from the cavity structure, a top electrode is grown on the surface of the piezoelectric layer at the end away from the cavity structure to obtain a resonator with a dual temperature compensation structure.

[0043] The method for fabricating a dual-temperature-compensated resonator provided in this application uses a room-temperature non-metallic bonding oxygen diffusion method to bond a high-quality silicon dioxide temperature compensation layer, thereby preparing a dual-temperature-compensated resonator. This method solves the problem that the high defect density and reduced crystal quality of amorphous silicon dioxide temperature compensation layers prepared by traditional deposition methods lead to a significant reduction in the performance of resonators and filters. By introducing a room-temperature non-metallic bonding oxygen diffusion method to form a high-quality silicon dioxide temperature compensation layer, the operating performance of the resonator is improved.

[0044] Specifically, in step S101, a release layer, a piezoelectric layer, and a patterned silicon layer are sequentially grown on the surfaces of the first silicon wafer and the second silicon wafer, respectively, including:

[0045] The first silicon wafer and the second silicon wafer were cleaned sequentially with acetone and hydrofluoric acid, respectively, to obtain the cleaned first silicon wafer and the cleaned second silicon wafer.

[0046] Using physical vapor deposition and chemical vapor deposition, a release layer, a piezoelectric layer, and a patterned silicon layer are sequentially grown on the surfaces of a first silicon wafer after cleaning and a second silicon wafer after cleaning, respectively.

[0047] In step S101, a cleaning step is introduced before growing the release layer, piezoelectric layer, and patterned silicon layer. This cleaning step includes using acetone to remove organic contaminants, followed by using hydrofluoric acid to remove the surface native oxide layer or metallic impurities. This pretreatment cleaning step effectively removes organic matter, particles, and native oxide layers from the silicon wafer surface. The clean surface provides highly active adhesion sites for subsequent film growth, thereby significantly improving the interfacial bonding strength between layers and the crystal quality of the film. Furthermore, using physical vapor deposition (PVD) and chemical vapor deposition (CVD) for film growth allows for precise control of the film thickness, composition, and microstructure, resulting in the release layer, piezoelectric layer, and patterned silicon layer. For example, the release layer can be grown using PVD, which enables high-density film growth and reduces internal defects; the patterned silicon layer can be grown using CVD, which provides good step coverage and uniformity, and is particularly suitable for growing complex patterns. It is precisely because of these refined processing and growth techniques that the prepared thin film layer possesses excellent physical and electrical properties, laying the foundation for the stability and high performance of subsequent devices. Specifically, the grown release layer is made of one of the following materials: aluminum gallium nitride (AlGaN), barium chloride (BaF2), calcium fluoride (CaF2), graphene, and boron nitride (BN); the piezoelectric layer is made of AlN (aluminum nitride), Sc... x Al 1-x N (scandium aluminum nitride), Al x Si 1-xAny one or more of N (aluminum silicon nitride); the patterned silicon layer is made of silicon.

[0048] Specifically, in step S102, after the above-mentioned thin film layer growth is completed, the surfaces of the first silicon wafer and the second silicon wafer with patterned silicon layers are pretreated, for example, by plasma activation treatment, to increase the hydrophilicity of the surface. Subsequently, at room temperature, the patterned silicon layer surfaces of the two wafers are aligned and brought into contact. Through the diffusion of oxygen atoms, a strong silicon dioxide bonding layer, namely a silicon dioxide temperature compensation layer, is formed between the two silicon layers, resulting in a first bonded substrate with a silicon dioxide temperature compensation layer at the center.

[0049] Specifically, in step S103, the first silicon wafer of the first bonding substrate and its corresponding release layer are peeled off by chemical etching, laser lift-off or physical lift-off to expose the piezoelectric layer and obtain the second bonding substrate.

[0050] Specifically, in step S104, the third silicon wafer with the etched cavity structure is bonded to one end of the exposed piezoelectric layer of the second bonding substrate using a room-temperature non-metallic bonding oxygen diffusion method, resulting in a third bonding substrate with a dual-temperature compensation structure, comprising:

[0051] The third silicon wafer is etched using etching technology to obtain a third silicon wafer with an etched cavity structure.

[0052] A bottom electrode and a silicon layer structure are grown on one end of the exposed piezoelectric layer of the second bonding substrate;

[0053] By using an oxygen diffusion method with room temperature non-metallic bonding, a third silicon wafer with an etched cavity structure is bonded to a silicon layer structure to obtain a third bonded substrate with a dual temperature compensation structure.

[0054] In step S104, etching the pre-prepared third silicon wafer using etching technology refers to using etching methods commonly used in semiconductor processes, such as dry etching with halogen gases like chlorine (Cl) and fluorine (F) and wet etching with liquid halogens like chlorine (Cl) and fluorine (F), to form a cavity structure of a predetermined shape and depth in a specific area of ​​the third silicon wafer. This cavity structure is essential for the resonator to achieve its resonant function, and its size and shape directly affect the device's resonant frequency and quality factor.

[0055] A conductive material is deposited on the exposed piezoelectric layer surface as a bottom electrode, followed by the deposition of a silicon material on top of the bottom electrode to form a silicon layer structure. The growth of the bottom electrode and the silicon layer structure can be achieved by methods such as physical vapor deposition (PVD) or chemical vapor deposition (CVD). The purpose of the bottom electrode is to provide electrical connections for the subsequent resonator, and the purpose of the silicon layer structure is to fabricate a dual-temperature compensated structure.

[0056] At room temperature, a third silicon wafer with an etched cavity structure is bonded to a silicon layer structure via oxygen atom diffusion between the oxide layers on the silicon surface. This achieves a tight bond between the two wafers, resulting in a third bonded substrate with a dual-temperature-compensated structure. This bonding method offers advantages such as high bond strength, fewer interface defects, and no need for high-temperature processing, effectively avoiding the impact of high temperatures on the properties of sensitive materials such as piezoelectric layers. The presence of the silicon layer structure provides an ideal silicon-silicon oxide interface for this bonding, ensuring the reliability and uniformity of the bond.

[0057] Specifically, in step S105, after peeling off the second silicon wafer and its corresponding release layer at the end furthest from the cavity structure, a top electrode is grown on the surface of the piezoelectric layer at that end, resulting in a dual-temperature-compensated resonator. For example, the second silicon wafer and its corresponding release layer can be removed again using selective etching or chemical dissolution, thereby exposing the surface of the piezoelectric layer on the other side. On this exposed piezoelectric layer surface, a top electrode is grown using evaporation, sputtering, or other thin-film deposition techniques. The top electrode can be made of a highly conductive metal, such as gold, aluminum, or molybdenum. At this point, the main structure of the entire dual-temperature-compensated resonator is complete.

[0058] In some optional embodiments, in step S103, any one silicon wafer and its corresponding release layer can be selected for peeling, and in step S105, another silicon wafer and its corresponding release layer can be peeled, so that steps S103 and S105 are modified accordingly as follows: In step S103, the second silicon wafer of the first bonding substrate and its corresponding release layer are peeled off to obtain a second bonding substrate with one end exposed to the piezoelectric layer; in step S105, after peeling off the first silicon wafer and its corresponding release layer at the end away from the cavity structure, a top electrode is grown on the surface of the piezoelectric layer at the end away from the cavity structure to obtain a resonator with a dual temperature compensation structure.

[0059] As described above, the fabrication method of this dual-temperature-compensated resonator involves sequentially growing a release layer, a piezoelectric layer, and a patterned silicon layer on the surfaces of a first silicon wafer and a second silicon wafer, respectively. The patterned silicon layers of the first and second silicon wafers are then bonded using a room-temperature non-metallic bonding oxygen diffusion method to form a silicon dioxide temperature-compensated layer, resulting in a first bonded substrate with a silicon dioxide temperature-compensated layer at its center. The first silicon wafer and its corresponding release layer are then removed from the first bonded substrate to obtain a second bonded substrate with one end exposing the piezoelectric layer. Finally, a third silicon wafer with an etched cavity structure is bonded to the second silicon wafer using a room-temperature non-metallic bonding oxygen diffusion method. Bonding is performed on one end of the exposed piezoelectric layer of the bonding substrate to obtain a third bonding substrate with a dual temperature compensation structure. After peeling off the second silicon wafer and its corresponding release layer at the end away from the cavity structure, a top electrode is grown on the surface of the piezoelectric layer at the end away from the cavity structure to obtain a resonator with a dual temperature compensation structure. This solves the problem of high defect density and reduced crystal quality in the amorphous silicon dioxide temperature compensation layer prepared by traditional deposition methods, which leads to a significant reduction in the performance of resonators and filters. The oxygen diffusion method of room temperature non-metallic bonding is introduced to form a high-quality silicon dioxide temperature compensation layer, thereby improving the working performance of the resonator.

[0060] Please refer to Figure 2 , Figure 2 The resonator with a dual temperature compensation structure provided in this application embodiment is prepared based on the above-described method for preparing a resonator with a dual temperature compensation structure. It includes a silicon substrate 101 (i.e., a third silicon wafer), a first temperature compensation layer 103 (i.e., a silicon dioxide temperature compensation layer formed by bonding the third silicon wafer with an etched cavity structure to the silicon layer structure in step S104 above), a bottom electrode 104, a piezoelectric layer 106, and a top electrode 107, which are connected from bottom to top.

[0061] The silicon substrate 101 has a protruding edge, forming a protrusion. The silicon substrate 101 and the first temperature compensation layer 103 are connected through the protrusion, forming a cavity structure 102 between the silicon substrate 101 and the first temperature compensation layer 103. A second temperature compensation layer 105 (i.e., a silicon dioxide temperature compensation layer formed by bonding the patterned silicon layers of the first silicon wafer and the second silicon wafer in step S102) is disposed in the piezoelectric layer 106. The upper surface of the first temperature compensation layer 103 is connected to the bottom electrode 104 and the piezoelectric layer 106 respectively.

[0062] In specific applications, the cavity structure 102 formed between the silicon substrate 101 and the first temperature compensation layer 103 not only provides acoustic isolation, but also the material properties of the first temperature compensation layer 103 (e.g., silicon dioxide) can provide first-level temperature compensation. Through the matching or cancellation of its thermal expansion coefficient with the thermal expansion coefficient of the piezoelectric layer 106, the resonant frequency of the device is initially stabilized.

[0063] Furthermore, the second temperature compensation layer 105 disposed in the piezoelectric layer 106 provides a second level of temperature compensation. This second temperature compensation layer 105 can be optimized according to the specific material and thickness of the piezoelectric layer 106 to more accurately offset the remaining temperature drift, thereby achieving frequency stability over a wider temperature range. Thus, through the specific stacking configuration of the silicon substrate 101, the first temperature compensation layer 103, the bottom electrode 104, the piezoelectric layer 106 (including the second temperature compensation layer 105), and the top electrode 107, as well as the introduction of the cavity structure 102, the overall temperature coefficient of the resonator with the dual temperature compensation structure is significantly reduced, ensuring the stability and reliability of the resonator performance under different temperature environments.

[0064] This resonator with a dual temperature compensation structure addresses the problem of high defect density and reduced crystal quality in traditional deposition methods for preparing amorphous silicon dioxide temperature compensation layers, which leads to a significant decrease in the performance of resonators and filters. By introducing a room-temperature non-metallic bonding oxygen diffusion method to form a high-quality silicon dioxide temperature compensation layer, the resonator and filter's performance is improved.

[0065] Specifically, the piezoelectric layer 106 is made of any one or more of aluminum nitride, scandium aluminum nitride, and silicon aluminum nitride.

[0066] In specific applications, the piezoelectric layer 106 is made of any one or more of aluminum nitride, aluminum scandium nitride, and aluminum nitride. The piezoelectric layer 106 is the core functional layer of the resonator, and its material selection directly affects the resonator's electromechanical coupling coefficient, quality factor, and temperature stability. Aluminum nitride (AlN) is a commonly used piezoelectric material with good piezoelectric properties and sound velocity characteristics. Aluminum scandium nitride (Sc)... x Al 1-x Aluminum nitride (Al₂O₃) is an alloy formed by doping aluminum nitride with scandium. By adjusting the scandium doping ratio, its piezoelectric constant and electromechanical coupling coefficient can be significantly improved, thereby enhancing the performance of the resonator. x AlSi 1-x Scandium (N) is an alloy formed by doping aluminum nitride with scandium. By adjusting the doping ratio of silicon, its piezoelectric constant and electromechanical coupling coefficient can be significantly improved, thereby enhancing the performance of the resonator. Choosing any one or more of these materials aims to optimize the overall performance of the resonator based on specific application requirements and performance indicators.

[0067] Specifically, the bottom electrode 104 is made of any one or more of the following materials: gold, silver, ruthenium, tungsten, molybdenum, iridium, aluminum, platinum, niobium, and hafnium.

[0068] In practical applications, the bottom electrode 104 is a key component of the resonator, and the choice of its material has a significant impact on the device's performance, especially its electrical performance and mechanical stability. Gold, silver, ruthenium, tungsten, molybdenum, iridium, aluminum, platinum, niobium, and hafnium all possess good conductivity, low resistivity, and controllability in thin-film deposition processes. These materials typically exhibit excellent conductivity, effectively reducing the series resistance of the device, thereby reducing energy loss and improving the resonator's quality factor (Q value) and the filter's insertion loss performance. Furthermore, these materials are easy to control in terms of crystal structure and stress state during thin-film deposition, which helps to form a flat and dense film, thus ensuring good growth of the piezoelectric layer 106 on top and effective excitation and transmission of acoustic waves. For example, gold and platinum have excellent chemical stability and conductivity and are often used in high-performance devices; tungsten and molybdenum are known for their high Young's modulus and good thermal stability, which help improve the device's mechanical strength and temperature stability.

[0069] Specifically, the top electrode 107 is made of any one or more of the following materials: gold, silver, ruthenium, tungsten, molybdenum, iridium, aluminum, platinum, niobium, and hafnium.

[0070] In practical applications, by selecting the aforementioned specific materials as the top electrode 107, excellent conductivity can be ensured, thereby effectively reducing electrical losses during signal transmission. Simultaneously, the acoustic properties of these materials, such as density and elastic modulus, can achieve good acoustic matching with the piezoelectric layer 106 and the bottom electrode 104, thus precisely controlling the resonant frequency and quality factor of the resonator. Therefore, the top electrode 107 not only serves as an electrical connection point but also as a crucial component of the acoustic resonant cavity; the choice of its material directly affects the overall acoustic response and electrical performance of the device.

[0071] Specifically, the bottom electrode 104 and the top electrode 107 have the same thickness.

[0072] In practical applications, the design of the bottom electrode 104 and the top electrode 107 having the same thickness ensures that the acoustic wave propagation path and electric field distribution inside the resonator are more symmetrical and uniform during operation. This symmetry helps reduce parasitic effects and energy losses caused by inconsistent electrode thicknesses, thereby improving the resonator's quality factor (Q value) and frequency response flatness. Furthermore, electrodes of the same thickness also contribute to more precise impedance matching, further optimizing the resonator's power transfer efficiency and ability to suppress out-of-band spurious responses.

[0073] As can be seen from the above, the resonator with the dual temperature compensation structure solves the problem of high defect density and reduced crystal quality in the traditional deposition method for preparing amorphous silicon dioxide temperature compensation layers, which leads to a significant reduction in the performance of the resonator and filter. By introducing the first and second temperature compensation layers obtained by oxygen diffusion bonding using room temperature non-metallic bonding, the performance of the resonator and filter is significantly improved.

[0074] This application provides a filter with a dual-temperature-compensated structure, including the aforementioned dual-temperature-compensated resonator. The filter is composed of multiple dual-temperature-compensated resonators, inheriting the dual-temperature-compensated characteristics of the resonator, thereby effectively suppressing the influence of temperature changes on the filter's frequency response and improving the filter's temperature stability. This dual-temperature-compensated structure utilizes the characteristics of multiple dual-temperature-compensated resonators exhibiting low impedance (in series resonance) or high impedance (in parallel resonance) to signals near a specific frequency (resonant frequency), thus achieving filtering functionality.

[0075] In the embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. Furthermore, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Additionally, the displayed or discussed mutual couplings, direct couplings, or communication connections may be through some communication interfaces; indirect couplings or communication connections between devices or units may be electrical, mechanical, or other forms.

[0076] Furthermore, the units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment, depending on actual needs.

[0077] Furthermore, the functional modules in the various embodiments of this application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0078] In this document, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, without necessarily requiring or implying any such actual relationship or order between these entities or operations.

[0079] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A method for manufacturing a dual temperature compensated resonator, for manufacturing a dual temperature compensated resonator, characterized by, The preparation method of the double-temperature compensation structure resonator comprises the following steps: a peeling layer, a piezoelectric layer and a patterned silicon layer are sequentially grown on surfaces of a first silicon wafer and a second silicon wafer respectively; the patterned silicon layers of the first silicon wafer and the second silicon wafer are bonded by an oxygen diffusion method of non-metallic bonding at room temperature to form a silicon dioxide temperature compensation layer, and a first bonded substrate provided with the silicon dioxide temperature compensation layer at the center is obtained; the first silicon wafer and the corresponding peeling layer of the first bonded substrate are peeled off to obtain a second bonded substrate with the piezoelectric layer exposed at one end; a third silicon wafer etched with a cavity structure is bonded to one end of the exposed piezoelectric layer of the second bonded substrate by an oxygen diffusion method of non-metallic bonding at room temperature to obtain a third bonded substrate provided with a double-temperature compensation structure; after the second silicon wafer away from the cavity structure and the corresponding peeling layer are peeled off, a top electrode is grown on the surface of the piezoelectric layer away from the cavity structure to obtain a double-temperature compensation structure resonator. a third silicon wafer etched with a cavity structure is bonded to one end of the exposed piezoelectric layer of the second bonded substrate by an oxygen diffusion method of non-metallic bonding at room temperature to obtain a third bonded substrate provided with a double-temperature compensation structure, comprising: a third silicon wafer is etched by an etching technology to obtain a third silicon wafer etched with a cavity structure; a bottom electrode and a silicon layer structure are grown on the surface of one end of the exposed piezoelectric layer of the second bonded substrate; the third silicon wafer etched with a cavity structure is bonded to the silicon layer structure by an oxygen diffusion method of non-metallic bonding at room temperature to form another silicon dioxide temperature compensation layer, and a third bonded substrate provided with a double-temperature compensation structure is obtained.

2. The method of claim 1, wherein the method further comprises: a peeling layer, a piezoelectric layer and a patterned silicon layer are sequentially grown on surfaces of a first silicon wafer and a second silicon wafer respectively, comprising: the first silicon wafer and the second silicon wafer are cleaned by acetone and hydrofluoric acid respectively to obtain a cleaned first silicon wafer and a cleaned second silicon wafer; a peeling layer, a piezoelectric layer and a patterned silicon layer are sequentially grown on surfaces of the cleaned first silicon wafer and the cleaned second silicon wafer by physical vapor deposition and chemical vapor deposition.

3. The method of claim 1, wherein the method further comprises: The material of the peeling layer is one of aluminum gallium nitride, barium chloride, calcium fluoride, graphene and boron nitride.

4. A resonator of the double temperature compensation structure, characterized by The double-temperature compensation structure resonator is prepared by the preparation method of the double-temperature compensation structure resonator according to claim 1, and comprises a silicon substrate (101), a first temperature compensation layer (103), a bottom electrode (104), a piezoelectric layer (106) and a top electrode (107) connected in sequence from bottom to top; The silicon substrate (101) is protruded at the edge to form a protruding part, and the silicon substrate (101) and the first temperature compensation layer (103) are connected through the protruding part, so that a cavity structure (102) is formed between the silicon substrate (101) and the first temperature compensation layer (103); the second temperature compensation layer (105) is arranged in the piezoelectric layer (106); and the upper surface of the first temperature compensation layer (103) is connected with the bottom electrode (104) and the piezoelectric layer (106) respectively.

5. The dual temperature-compensated resonator of claim 4, wherein, The material of the piezoelectric layer (106) is any one or more of aluminum nitride, scandium aluminum nitride and aluminum nitride.

6. The dual temperature-compensated resonator of claim 4, wherein, The material of the bottom electrode (104) is any one or more of gold, silver, ruthenium, tungsten, molybdenum, iridium, aluminum, platinum, niobium, hafnium.

7. The dual temperature-compensated resonator of claim 4, wherein, The material of the top electrode (107) is any one or more of gold, silver, ruthenium, tungsten, molybdenum, iridium, aluminum, platinum, niobium, hafnium.

8. The dual temperature-compensated resonator of claim 4, wherein, The thickness of the bottom electrode (104) and the top electrode (107) is the same.

9. A filter of double temperature compensation structure, characterized by A resonator comprising the dual temperature compensation structure of claim 4.

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