CN112311347B - Structure capable of improving quality factor Q value of film bulk acoustic resonator - Google Patents
Structure capable of improving quality factor Q value of film bulk acoustic resonator Download PDFInfo
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- CN112311347B CN112311347B CN202011109253.4A CN202011109253A CN112311347B CN 112311347 B CN112311347 B CN 112311347B CN 202011109253 A CN202011109253 A CN 202011109253A CN 112311347 B CN112311347 B CN 112311347B
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- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 4
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- PMHQVHHXPFUNSP-UHFFFAOYSA-M copper(1+);methylsulfanylmethane;bromide Chemical compound Br[Cu].CSC PMHQVHHXPFUNSP-UHFFFAOYSA-M 0.000 description 3
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- 229910052581 Si3N4 Inorganic materials 0.000 description 2
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- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 1
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- HFGPZNIAWCZYJU-UHFFFAOYSA-N lead zirconate titanate Chemical compound [O-2].[O-2].[O-2].[O-2].[O-2].[Ti+4].[Zr+4].[Pb+2] HFGPZNIAWCZYJU-UHFFFAOYSA-N 0.000 description 1
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- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 1
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Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
- H03H9/02—Details
- H03H9/02007—Details of bulk acoustic wave devices
- H03H9/02086—Means for compensation or elimination of undesirable effects
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H3/00—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators
- H03H3/007—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators for the manufacture of electromechanical resonators or networks
- H03H3/02—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators for the manufacture of electromechanical resonators or networks for the manufacture of piezoelectric or electrostrictive resonators or networks
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
- H03H9/15—Constructional features of resonators consisting of piezoelectric or electrostrictive material
- H03H9/17—Constructional features of resonators consisting of piezoelectric or electrostrictive material having a single resonator
- H03H9/171—Constructional features of resonators consisting of piezoelectric or electrostrictive material having a single resonator implemented with thin-film techniques, i.e. of the film bulk acoustic resonator [FBAR] type
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H3/00—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators
- H03H3/007—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators for the manufacture of electromechanical resonators or networks
- H03H3/02—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators for the manufacture of electromechanical resonators or networks for the manufacture of piezoelectric or electrostrictive resonators or networks
- H03H2003/023—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators for the manufacture of electromechanical resonators or networks for the manufacture of piezoelectric or electrostrictive resonators or networks the resonators or networks being of the membrane type
Landscapes
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Piezo-Electric Or Mechanical Vibrators, Or Delay Or Filter Circuits (AREA)
Abstract
The invention discloses a structure capable of improving the quality factor Q value of a film bulk acoustic resonator, which comprises a substrate, a piezoelectric oscillation stack, a first cavity and a second cavity, wherein the substrate is provided with a first cavity and a second cavity; a termination layer may also be included; the piezoelectric oscillation stack comprises a lower electrode, a piezoelectric layer and an upper electrode, wherein the width of the second cavity is equal to the shortest distance between the second cavity and the edge of the first cavity. According to the invention, the state of the FBAR piezoelectric oscillation stack can be optimized by adding the cavity structure or combining with the change part structure, so that the boundary acoustic impedance condition is improved well, the existence of parasitic transverse waves is restrained, the purpose of improving the Q value of a device is further achieved, the yield of the product is also improved greatly, and the market competitiveness of the product is enhanced greatly.
Description
Technical Field
The invention belongs to the technical field of MEMS devices, and relates to a structure capable of improving the quality factor Q value of a film bulk acoustic resonator.
Background
With the rapid development of mobile communication technology, market demands for high-frequency resonators and filters are increasing. Compared with the traditional microwave ceramic resonator and the surface wave resonator, the Film Bulk Acoustic Resonator (FBAR) has the advantages of small volume, low loss, high quality factor, large power capacity, high resonant frequency and the like, so that the Film Bulk Acoustic Resonator (FBAR) has wide application prospect in the related fields, especially in the aspect of high-frequency communication, and becomes a popular research in the industry and academia.
Currently, there are three main types of main FBAR structures: back-etched, air-gap, and solid-state assembled. The back etching type structure adopts a bulk micromachining technology to etch and remove most substrate materials from the surface of the substrate in a reverse way, and forms an interface between the piezoelectric oscillation stack and air, so that sound waves are limited in the piezoelectric oscillation. The bulk removal of the substrate tends to affect the mechanical strength of the device, greatly reducing yield. The solid assembly type structure realizes the limitation of sound waves by alternately forming the Bragg reflection layers through the high and low acoustic impedance layers of the substrate, the multilayer thin film is required to be prepared in the technical process of the structure, the structure is complicated and high in cost, and the Bragg reflection layers have poor sound wave limiting effect compared with air, so that the device performance is poor and the Q value is low. The air gap bulk acoustic wave resonator is based on surface micromachining technology, and an air gap is formed on the upper surface of a silicon wafer by filling sacrificial materials and removing the sacrificial materials to limit acoustic waves in a piezoelectric vibrating pile. The structure can achieve good sound wave limiting effect without removing a large amount of substrates to cause the firmness of the device to be reduced or forming the acoustic reflection layers stacked layer by a complicated process, and a higher Q value is obtained.
The thin film bulk acoustic resonator can only excite the acoustic mode, namely longitudinal mechanical wave, and the ideal mode is that the acoustic wave propagates along the thickness direction of the piezoelectric layer. But the acoustic wave has not only TE mode but also Rayleigh-Lamb mode, i.e. transverse mechanical wave, within the piezoelectric vibrating stack. The lateral propagation of acoustic waves in the piezoelectric layer can adversely affect the quality factor (Q) of the FBAR device, particularly where the energy of the lateral mechanical waves is lost at the FBAR device interface, which can lead to a loss of desired longitudinal mechanical wave energy, ultimately resulting in a reduction in the quality factor (Q) of the FBAR device. According to the invention, the aim of improving boundary acoustic impedance conditions and inhibiting the existence of parasitic transverse waves is fulfilled by changing part of the structure of the film bulk acoustic resonator, and the loss of expected longitudinal mechanical wave energy is reduced, so that the aim of improving the quality factor (Q) of the device is fulfilled.
Object of the Invention
Aiming at the defects of the prior art, the invention provides a structure and a design method capable of improving the quality factor Q value of a film bulk acoustic resonator, and the purposes of changing boundary acoustic impedance conditions, inhibiting the existence of parasitic transverse waves, reducing the loss of expected longitudinal mechanical wave energy and further improving the quality factor Q value of a device and the product yield are achieved by changing part of the structure of the film bulk acoustic resonator.
The technical scheme adopted by the invention is as follows:
A structure capable of improving quality factor Q value of a film bulk acoustic resonator comprises a substrate, a termination layer, a piezoelectric oscillation stack, a first cavity and a second cavity; the piezoelectric oscillation stack comprises a lower electrode, a piezoelectric layer and an upper electrode, the first cavity is arranged on the surface of the substrate, the termination layer is arranged between the substrate and the lower electrode of the piezoelectric oscillation stack, the second cavity is arranged between the termination layer and the piezoelectric oscillation stack, and the first cavity and the second cavity are separated by the termination layer; the width of the second cavity is equal to the shortest distance between the second cavity and the edge of the first cavity.
Further, a third cavity is arranged around the second cavity between the lower electrode and the piezoelectric layer;
Furthermore, the third cavity is filled with the lower electrode material, so that the thickness of the lower electrode at the position of the third cavity is larger than that of the lower electrode at other positions;
further, the lower electrode material right above the second cavity is thinned, so that the thickness of the lower electrode at the position where the lower electrode material is located is smaller than that of the lower electrode at other positions;
The other structure capable of improving the quality factor Q value of the film bulk acoustic resonator comprises a substrate, a piezoelectric oscillation stack, a first cavity and a second cavity; the piezoelectric oscillation stack comprises a lower electrode, a piezoelectric layer and an upper electrode, the first cavity is arranged on the surface of the substrate, the second cavity is arranged on the periphery of the first cavity and between the substrate and the piezoelectric oscillation stack, and a partition cavity is further arranged in the structure, so that only a part of piezoelectric oscillation stack exists above the second cavity, namely the piezoelectric oscillation stack forms a suspended structure above the second cavity;
in each of the above embodiments, further, the thin film bulk acoustic resonator is a cavity type FBAR, and the first cavity is formed by releasing a sacrificial layer; or the film bulk acoustic resonator is an FBAR of the Bragg reflection layer structure, and the Bragg reflection layer structure is filled in the first cavity;
Further, the second cavity is obtained by releasing the sacrificial layer, and the section of the second cavity is any one or any combination of a plurality of ladder-shaped, triangular, rectangular and square-shaped;
After the structural design is adopted, the relation between the Q value of the FBAR obtained through simulation and the width of the second cavity can be combined, and the proper width of the second cavity can be selected to obtain the required Q value;
According to the invention, the cavity structure is added or part of the structure is combined and changed, so that the state of the partial FBAR piezoelectric oscillation stack can be optimized, the boundary acoustic impedance condition is improved well, the existence of parasitic transverse waves is restrained, the purpose of improving the Q value of a device is achieved, the yield of the product is improved greatly, and the market competitiveness of the product is enhanced greatly.
Drawings
FIG. 1 is a schematic diagram of a structure for improving the Q value of a film bulk acoustic resonator according to the present invention; wherein the first cavity 101 is a cavity;
FIG. 2 is a schematic diagram of another structure for improving the Q of a thin film bulk acoustic resonator according to the present invention; wherein the first cavity 101 is filled with a bragg reflection layer structure;
FIG. 3 is a graph of Q versus lateral width of the second cavity 103 for the resonator of the structure of FIG. 1 in parallel; it can be seen that as the lateral width of the cavity 103 increases, maxima such as 301, 302, 303 occur, minima such as 304, 305, 306 occur, and maxima such as 301, 302, 303 are much greater than the initial point, i.e., FBAR structures of the second cavity are not added;
FIG. 4 is a graph of Q versus lateral width of the second cavity 103 for the resonator of the structure of FIG. 2 in series; it can be seen that as the lateral width of the cavity 103 increases, maxima such as 307, 308, 309, and minima such as 310, 311, 307, 308, 309, etc. occur, the maxima are much greater than the initial point, i.e., the FBAR structure of the second cavity is not added;
FIG. 5 is a schematic diagram of another structure for improving the Q of a thin film bulk acoustic resonator according to the present invention; wherein the first cavity 101 is a cavity, and a cavity, i.e., a third cavity 108, is further provided around the second cavity 103 between the lower electrode 105 and the piezoelectric layer 106;
FIG. 6 is a schematic diagram of another structure for improving the Q of a thin film bulk acoustic resonator according to the present invention; wherein the first cavity 101 is filled with a Bragg reflection layer structure, and a cavity, namely a third cavity 108, is further arranged between the lower electrode 105 and the piezoelectric layer 106 around the second cavity 103;
FIG. 7 is a schematic diagram of another structure for improving the Q of a thin film bulk acoustic resonator according to the present invention; wherein the first cavity 101 is a cavity; filling the third cavity 108 in the structure of fig. 5 with a lower electrode material such that the lower electrode thickness is greater than the lower electrode thickness elsewhere;
FIG. 8 is a schematic diagram of another structure for improving the Q of a thin film bulk acoustic resonator according to the present invention; wherein the first cavity 101 is filled with a bragg reflection layer structure; filling the third cavity 108 in the structure of fig. 6 with a lower electrode material such that the lower electrode thickness is greater than the lower electrode thickness elsewhere;
FIG. 9 is a schematic diagram of another structure for improving the Q of a thin film bulk acoustic resonator according to the present invention; the first cavity 101 is a cavity, and the thickness of the lower electrode material right above the second cavity 103 is smaller than that of the lower electrode at other positions;
FIG. 10 is a schematic diagram of another structure for improving the Q of a thin film bulk acoustic resonator according to the present invention; the first cavity 101 is filled with a Bragg reflection layer structure, and the thickness of the lower electrode material right above the second cavity 103 is smaller than that of the lower electrodes at other positions;
FIG. 11 is a schematic diagram of another structure for improving the Q of a thin film bulk acoustic resonator according to the present invention; wherein the first cavity 101 is a cavity, no termination layer exists in the structure, the second cavity 103 is positioned at the periphery of the first cavity 101 and between the substrate 100 and the piezoelectric oscillation stack, and a partition cavity 109 is further provided to enable the piezoelectric oscillation stack to form a suspended structure above the second cavity 103;
FIG. 12 is a schematic diagram of another structure for improving the Q of a thin film bulk acoustic resonator according to the present invention; the first cavity 101 is filled with a Bragg reflection layer structure, no termination layer exists in the structure, the second cavity 103 is arranged at the periphery of the first cavity 101 and between the substrate 100 and the piezoelectric oscillation stack, and a partition cavity 109 is further arranged to enable the piezoelectric oscillation stack to form a suspended structure above the second cavity 103;
In the figure: 100 substrate, 101 first cavity, 102 termination layer, 103 second cavity, 104 shortest distance of second cavity edge from first cavity edge, 105 lower electrode, 106 piezoelectric layer, 107 upper electrode, 108 third cavity, 109 partition cavity.
Detailed Description
The FBAR structure comprises a substrate, a first cavity, a piezoelectric oscillation stack and a second cavity; compared with the conventional FBAR, the invention can change the state of part of the FBAR piezoelectric oscillation stack by adding a specific second cavity and/or changing part structures, thereby better changing boundary acoustic impedance conditions, inhibiting the existence of parasitic transverse waves, finally achieving the purpose of improving the Q value of the device and greatly improving the yield of the product.
The method of the present invention is further described with reference to specific examples, as shown in fig. 1, which is a schematic structural diagram of the present invention for improving the Q value of a thin film bulk acoustic resonator; it comprises a substrate 100, a termination layer 102, a piezoelectric oscillation stack, a first cavity 101, a second cavity 103; the piezoelectric oscillation stack comprises a lower electrode 105, a piezoelectric layer 106 and an upper electrode 107, the first cavity 101 is arranged on the surface of the substrate 100, the termination layer 102 is arranged between the substrate 100 and the lower electrode 105 of the piezoelectric oscillation stack, the second cavity 103 is arranged between the termination layer 102 and the piezoelectric oscillation stack, and the first cavity 101 and the second cavity 103 are separated by the termination layer; the width of the second cavity 103 is equal to the shortest distance 104 of the second cavity from the edge of the first cavity.
The preparation method comprises the following specific steps: 1) Cleaning the silicon substrate 100, and ultrasonically washing the silicon substrate with acetone and isopropanol to orient the silicon substrate to be (111) or (100); 2) Etching a first cavity 101 with a depth of 3um and a lateral width of 200um on a silicon substrate by adopting ICP etching based on a BOSCH process; 3) Depositing 3-5um phosphosilicate glass (PSG) as a sacrificial layer material on the surface of the substrate 100 containing the first cavity by a conventional Low Pressure Chemical Vapor Deposition (LPCVD) process, and patterning by Chemical Mechanical Polishing (CMP); 4) Depositing 100nm C-axis oriented aluminum nitride (ALN) on the surfaces of the substrate 100 and the sacrificial layer by using a conventional Low Pressure Chemical Vapor Deposition (LPCVD) process or a magnetron sputtering process and the like as a termination layer 102; 5) Depositing 300nm phosphosilicate glass (PSG) as a sacrificial layer material on the surface of the termination layer 102 by a conventional Low Pressure Chemical Vapor Deposition (LPCVD) process, and forming a pattern with a lateral width of 5um at 5um from the edge of the first cavity by plasma or wet etching; 6) Depositing a 250nm metal molybdenum first electrode 105 on the surfaces of the termination layer 102 and the sacrificial layer material by adopting methods such as thermal evaporation or magnetron sputtering, and patterning by adopting a plasma or wet etching method; 7) Sputtering an AlN piezoelectric film layer 106 with C-axis orientation of 1 μm on the surface of the termination layer 102 and the metal molybdenum electrode; 8) A 200nm metal molybdenum second electrode 107 is deposited on the piezoelectric layer 106 by adopting methods such as thermal evaporation or magnetron sputtering; patterning by adopting a plasma or wet etching method; 9) Removing the sacrificial layer by wet etching or HF fumigation to form a first cavity 101 and a second cavity 103;
The material of the substrate 100 of the device may be one or any combination of glass, silicon carbide, silicon nitride, ceramic, etc., and the first cavity on the substrate 100 may be formed by plasma etching, wet etching, etc. The cross section of the first cavity can be one or any combination of ladder-shaped, triangle-shaped and rectangular square, the depth of the first cavity is 1-10um, and the transverse width of the first cavity is 50-400um. The cavity width is smaller than the device layer.
The material of the stop layer 102 can be one or any combination of silicon nitride, aluminum nitride, silicon oxide and aluminum oxide, and the thickness is 30-100nm, and mainly plays a role in stopping etching in the 103 patterning process.
The second cavity 103 may have a depth of 200-400nm, and a pattern having a lateral width of 0.1um-100um is formed at 0.1um-100um from the edge of the first cavity 101 by plasma or wet etching.
The lower electrode 105 may be made of one or any combination of molybdenum, gold, platinum, copper, aluminum, silver, titanium, tungsten, and nickel, and has a thickness of 20-1000nm, and is patterned by plasma etching, wet etching, or the like. In order to improve the deposition quality of the electrode film layer under 104, a 10-100nm piezoelectric layer seed layer (not shown) may be deposited.
The piezoelectric layer 106 material may be aluminum nitride, doped aluminum nitride, zinc oxide, lithium nickelate, lead zirconate titanate, etc.
The upper electrode 107 may be one or any combination of molybdenum, gold, platinum, copper, aluminum, silver, titanium, tungsten, and nickel, and has a thickness of 20-1000nm, and is patterned by plasma etching, wet etching, or the like.
The thin film bulk acoustic resonator in the above example may be a cavity type FBAR, that is, the first cavity forms a cavity by releasing the sacrificial layer; or the film bulk acoustic resonator can also be an FBAR of the Bragg reflection layer structure, namely the first cavity is filled with the Bragg reflection layer structure; in any structure, based on the structural design of the invention, the Q value can be correspondingly improved, and as shown in figures 3 and 4, the proper width value of the second cavity can be selected according to the requirement.
The above embodiment is only one specific example of the present invention, and in addition, the structure of the present invention may further be as shown in fig. 5-10, and by adding the second cavity, the Q value of the FBAR may be improved compared to the structure without adding the second cavity.
FIG. 11 is a schematic diagram showing another structure for improving the Q value of a thin film bulk acoustic resonator according to the present invention; it comprises a substrate 100, a piezoelectric oscillation stack, a first cavity 101, a second cavity 103; the piezoelectric oscillation stack comprises a lower electrode 105, a piezoelectric layer 106 and an upper electrode 107, the first cavity 101 is arranged on the surface of the substrate 100, the second cavity 103 is arranged at the periphery of the first cavity 101 and between the substrate 100 and the piezoelectric oscillation stack, and a partition cavity for completely partitioning the piezoelectric oscillation stack is also arranged in the structure, so that only a part of piezoelectric oscillation stack exists above the second cavity 103, namely the piezoelectric oscillation stack forms a suspended structure above the second cavity 103; the film bulk acoustic resonator may be a cavity type FBAR, that is, the first cavity forms a cavity by releasing the sacrificial layer; or the film bulk acoustic resonator may be an FBAR with a bragg reflection layer structure, that is, the first cavity is filled with the bragg reflection layer structure as shown in fig. 12; the Q value of the structure can be correspondingly improved based on the structural design of the invention no matter which structure is adopted.
The present invention is not limited to the above-mentioned embodiments, but is intended to be limited to the above-mentioned embodiments, and any modifications, equivalents and modifications can be made to the above-mentioned embodiments without departing from the scope of the invention.
Claims (3)
1. The structure capable of improving the quality factor Q value of the film bulk acoustic resonator is characterized by comprising a substrate, a piezoelectric oscillation stack, a first cavity and a second cavity; the piezoelectric oscillation stack comprises a lower electrode, a piezoelectric layer and an upper electrode, the first cavity is arranged on the surface of the substrate, the second cavity is arranged at the periphery of the first cavity and between the substrate and the piezoelectric oscillation stack, and a partition cavity is further arranged in the structure, so that only a part of piezoelectric oscillation stack exists above the second cavity, namely the piezoelectric oscillation stack forms a suspended structure above the second cavity; and thinning the lower electrode material right above the second cavity so that the thickness of the lower electrode at the position where the lower electrode is positioned is smaller than that of the lower electrode at other positions.
2. The structure of claim 1, wherein the thin film bulk acoustic resonator is a cavity type FBAR, and the first cavity is formed by releasing a sacrificial layer; or the film bulk acoustic resonator is an FBAR of the Bragg reflection layer structure, and the Bragg reflection layer structure is filled in the first cavity.
3. The structure of claim 1, wherein the second cavity is obtained by releasing the sacrificial layer, and the cross section of the second cavity is any one or any combination of a plurality of ladder-shaped, triangular, rectangular and square.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011109253.4A CN112311347B (en) | 2020-10-16 | 2020-10-16 | Structure capable of improving quality factor Q value of film bulk acoustic resonator |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011109253.4A CN112311347B (en) | 2020-10-16 | 2020-10-16 | Structure capable of improving quality factor Q value of film bulk acoustic resonator |
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| CN112311347A CN112311347A (en) | 2021-02-02 |
| CN112311347B true CN112311347B (en) | 2024-05-24 |
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| CN113193847B (en) * | 2021-03-24 | 2023-07-21 | 深圳市封神微电子有限公司 | Structure for improving quality factor and optimizing stress distribution of film bulk acoustic resonator |
| CN113364422A (en) * | 2021-06-18 | 2021-09-07 | 深圳市封神微电子有限公司 | Film bulk acoustic resonator with ring electrode |
| CN113489470B (en) * | 2021-07-02 | 2024-05-03 | 杭州树芯电子科技有限公司 | Packaging method of film bulk acoustic resonator |
| CN114938213B (en) * | 2022-06-08 | 2023-04-14 | 武汉敏声新技术有限公司 | Film bulk acoustic resonator and preparation method thereof |
| CN115833779A (en) * | 2023-02-15 | 2023-03-21 | 成都频岢微电子有限公司 | Wave-shaped bulk acoustic wave resonator |
| CN116032236B (en) * | 2023-02-15 | 2023-06-06 | 成都频岢微电子有限公司 | Bulk acoustic wave ear-shaped channel resonator |
| CN117375565B (en) * | 2023-11-14 | 2024-06-14 | 武汉敏声新技术有限公司 | Acoustic wave filter and preparation method thereof |
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| CN111082774A (en) * | 2019-10-23 | 2020-04-28 | 诺思(天津)微系统有限责任公司 | Bulk acoustic wave resonator having electrode with void layer, filter, and electronic device |
| CN111245393A (en) * | 2019-12-04 | 2020-06-05 | 诺思(天津)微系统有限责任公司 | Bulk acoustic wave resonator, method of manufacturing the same, filter, and electronic apparatus |
| CN111600569A (en) * | 2020-04-29 | 2020-08-28 | 诺思(天津)微系统有限责任公司 | Bulk acoustic wave resonator, method of manufacturing the same, filter, and electronic apparatus |
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| US10340885B2 (en) * | 2014-05-08 | 2019-07-02 | Avago Technologies International Sales Pte. Limited | Bulk acoustic wave devices with temperature-compensating niobium alloy electrodes |
| CN107181470B (en) * | 2016-03-10 | 2020-10-02 | 中芯国际集成电路制造(上海)有限公司 | Film bulk acoustic resonator, semiconductor device and method of manufacturing the same |
| US10263587B2 (en) * | 2016-12-23 | 2019-04-16 | Avago Technologies International Sales Pte. Limited | Packaged resonator with polymeric air cavity package |
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| CN111082774A (en) * | 2019-10-23 | 2020-04-28 | 诺思(天津)微系统有限责任公司 | Bulk acoustic wave resonator having electrode with void layer, filter, and electronic device |
| CN111245393A (en) * | 2019-12-04 | 2020-06-05 | 诺思(天津)微系统有限责任公司 | Bulk acoustic wave resonator, method of manufacturing the same, filter, and electronic apparatus |
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