CN115333497A - Preparation method of film cavity acoustic wave resonator and film cavity acoustic wave resonator - Google Patents
Preparation method of film cavity acoustic wave resonator and film cavity acoustic wave resonator Download PDFInfo
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Images
Classifications
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- 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
- H03H9/02—Details
- H03H9/02007—Details of bulk acoustic wave devices
-
- 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
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- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Physics & Mathematics (AREA)
- Acoustics & Sound (AREA)
- Piezo-Electric Or Mechanical Vibrators, Or Delay Or Filter Circuits (AREA)
Abstract
The invention discloses a preparation method of a film cavity acoustic wave resonator and the film cavity acoustic wave resonator. The piezoelectric ceramic comprises a silicon substrate, a bottom electrode layer, a piezoelectric layer and a top electrode layer which are sequentially arranged from bottom to top, wherein a cavity which is sunken downwards is formed in the top surface of the silicon substrate, and the bottom electrode layer is a bottom phenylene layer; the preparation method comprises the following steps of S1: processing the silicon substrate by an RCA cleaning process, drying, etching a groove on the surface of the silicon substrate by a dry method, and depositing a sacrificial layer at the groove; step S2: depositing a material of a phenylene bottom electrode layer on the silicon substrate; and step S3: bonding piezoelectric layer materials; and step S4: depositing a top electrode layer material, and etching the top electrode layer material to obtain a pattern; step S5: and obtaining a release window around the cavity through dry etching, injecting an etching solution into the release window, and removing the loose sacrificial layer to form an air cavity. The invention can simultaneously improve the Q value and the electromechanical coupling coefficient of the resonator.
Description
Technical Field
The invention relates to the technical field of bulk acoustic wave resonators, in particular to a preparation method of a film cavity bulk acoustic wave resonator and the film cavity bulk acoustic wave resonator.
Background
As people have increasingly high data transmission efficiency and demand for portable mobile terminals, wireless communication technology has been rapidly developed. In a communication system, a radio frequency front end is responsible for receiving and transmitting radio frequency signals. In the radio frequency front end module, the filter mainly plays a role in effectively filtering signals, so that the signals are effectively transmitted in a specific frequency band, and the signals outside the required frequency band are filtered.
The fbar filter is a short name of a filter bulk acoustic resonator filter, which is a thin film bulk acoustic resonator filter, and is manufactured by means of a mems technology and a thin film technology by using a silicon substrate, unlike the former filter, and the present fbar filter has characteristics slightly higher than that of a common saw filter. The FBAR filter has a series of advantages of integration, high working frequency (0.6 GHz-24 GHz), high power capacity, high Q value and the like, and is formed by cascading series-parallel FBAR resonance units. The fbar technology combines the advantages of the dielectric filtering technology and the surface acoustic wave filtering technology, is widely applied to the fields of filters, oscillators and the like, and becomes the mainstream technology of the next generation of wireless communication filtering. The working principle is as follows: the piezoelectric film is deformed under the action of an external electric field and the reverse piezoelectric effect, when the external field is an alternating electromagnetic field, the piezoelectric film generates mechanical vibration to generate sound waves, and the sound waves are totally reflected on the contact surface of the electrode and the air and are completely bound in the device. At a particular frequency, the acoustic wave creates a standing wave inside the device, which in turn converts the mechanical energy into electromagnetic energy, which is transmitted through the resonant cell at the particular frequency.
At present, the FBAR device has the advantages of low insertion loss, high frequency selectivity and the like, but the electrode of the FBAR device has a certain thickness, so that the acoustic path is prolonged equivalently. Second, the electromechanical coupling coefficient (k) of the FBAR t 2 ) Q is two key factors, and Q and k t 2 There are mutual constraints when raising the Q value, k t 2 Will decrease if k is increased t 2 Then the Q value is sacrificed so that the transfer characteristic of the resonator cannot be improved.
Disclosure of Invention
In order to solve the above problems, a main object of the present invention is to provide a method for manufacturing a film bulk acoustic resonator and a film bulk acoustic resonator, which can simultaneously improve a Q value and an electromechanical coupling coefficient of the resonator, thereby improving signal conversion efficiency.
In order to achieve the purpose, the invention adopts the technical scheme that:
a method for preparing a film bulk acoustic resonator comprises the following steps: the piezoelectric sensor comprises a silicon substrate, a bottom electrode layer, a piezoelectric layer and a top electrode layer which are sequentially arranged from bottom to top, wherein a cavity which is sunken downwards is formed in the top surface of the silicon substrate, and the bottom electrode layer is a bottom electrode layer of a phenylene group;
the preparation method comprises the following steps:
step S1: processing the silicon substrate by an RCA cleaning process, drying, etching a groove on the surface of the silicon substrate by a dry method, and depositing a sacrificial layer at the groove;
step S2: depositing a material of a phenylene bottom electrode layer on the silicon substrate;
and step S3: bonding piezoelectric layer materials, and etching the piezoelectric layer to form a required pattern;
and step S4: depositing a top electrode layer material, and etching the top electrode layer material to obtain a pattern;
step S5: and obtaining a release window around the cavity through dry etching, injecting corrosive solution into the release window, removing the loose sacrificial layer, and forming an air cavity to obtain the film cavity acoustic wave resonator.
Further, the depositing a sacrificial layer at the groove includes: a loose SiO2 layer is deposited on the SiO2 layer by PECVD.
Further, in step S2, the method further includes:
adding a trifluoromethanesulfonylation reagent into o-iodophenol, reacting the obtained product with a lithium reagent in a low-temperature solvent to prepare a biphenylene group, and then obtaining a biphenylene group bottom electrode layer material in a vapor deposition mode.
Further, in step S3, the method further includes:
step S31: depositing a piezoelectric material film on a silicon substrate through magnetron sputtering, and then carrying out heat treatment and inert gas protection treatment on the piezoelectric material film;
step S32: and (4) further growing the piezoelectric material with high crystal quality on the piezoelectric material film processed in the step (S31) by an organic metal compound chemical vapor deposition method, and then etching and stripping to remove the part except the piezoelectric material film so as to obtain the piezoelectric material.
Further, the horizontal areas of the bottom electrode layer and the top electrode layer are smaller than the horizontal area of the silicon substrate, and the bottom electrode layer and the top electrode layer extend from two ends of the piezoelectric layer respectively and completely cover the cavity.
Further, an inclination angle of 70-86 degrees is arranged between the inner side wall of the cavity and the bottom surface of the cavity.
Further, the piezoelectric layer comprises at least one piezoelectric material of AlN, znO and PTZ.
Further, the top electrode layer is composed of at least one of a biphenylene group, gold, copper, silver, aluminum, tungsten, platinum, molybdenum, rhodium, iridium, and titanium.
Further, the film bulk acoustic resonator includes a support base, and the silicon substrate is disposed on the support base.
A film bulk acoustic resonator is manufactured by executing the manufacturing method of the film bulk acoustic resonator.
The invention has the beneficial effects that:
the piezoelectric silicon substrate comprises a silicon substrate, a bottom electrode layer, a piezoelectric layer and a top electrode layer which are sequentially arranged from bottom to top, wherein a cavity which is sunken downwards is formed in the top surface of the silicon substrate, and the bottom electrode layer is a phenylene bottom electrode layer. The adoption of the bottom electrode layer of the continuous diphenylene can simultaneously improve the Q value and the electromechanical coupling coefficient of the resonator, thereby improving the signal conversion efficiency.
Drawings
Fig. 1 is a schematic cross-sectional view of the novel film bulk acoustic resonator of the present invention.
Fig. 2 is a flow chart of a method for manufacturing a film bulk acoustic resonator according to the present invention.
Fig. 3 is a flowchart of a method for manufacturing a film bulk acoustic resonator according to an embodiment of the present invention.
The reference numbers illustrate: 10. a support substrate; 20. a silicon substrate; 30. a cavity; 40. a bottom electrode layer; 50. a piezoelectric layer; 60. a top electrode layer.
Detailed Description
Referring to fig. 1-2, the present invention relates to a method for fabricating a film bulk acoustic resonator.
The film bulk acoustic resonator includes: the piezoelectric device comprises a silicon substrate 20, a bottom electrode layer 40, a piezoelectric layer 50 and a top electrode layer 60 which are sequentially arranged from bottom to top, wherein a cavity 30 which is recessed downwards is formed in the top surface of the silicon substrate 20, and the bottom electrode layer 40 is a phenylene bottom electrode layer 40; the silicon substrate 20 is made of a high-resistivity silicon material, and the resistivity of the high-resistivity silicon is 10000 Ω · m or more; the silicon material is used as the substrate of the film bulk acoustic resonator because the current technology of the silicon material is mature on one hand, and because the silicon material has many advantages in the process on the other hand. The top surface of the silicon substrate 20 is etched to form a cavity 30, and the technical effect of the cavity 30 is to reserve a space to make an electrode layer (it should be emphasized that the bottom electrode layer 40 and the top electrode layer 60 are collectively referred to as an electrode layer in this specification) vibrate on one hand, and to form a sound wave propagation interface on the other hand, to make sound waves totally reflect without leaking and propagating to the outside. When a high-frequency electric signal is applied to the electrode layers, the piezoelectric layer 50 sandwiched therebetween is internally polarized due to the inverse piezoelectric effect, and a reciprocating periodic mechanical deformation and vibration having the same frequency as the input electric signal are generated, and the mechanical deformation and vibration propagates between the bottom electrode layer 40 and the top electrode layer 60 in the form of bulk acoustic waves, and the propagation direction of the acoustic waves is related to the distribution of the electrode layers and the crystallographic orientation of the piezoelectric material. And when the mechanical energy is converted into the electric energy, a conductor is needed for transmitting signals, so that an electrode is needed. It should be noted that the bottom electrode layer 40 is a bottom electrode layer 40 of a biphenylene group, the conductivity of the material of the biphenylene group is the same as that of a metal under the condition that the lattice width is only 21 atoms, and the graphene has the conductivity of a semiconductor under the same thickness; therefore, the FBAR electrode layer made of the continuous diphenyl-ene material can obtain a good Q value, can be made to be very thin, and has great improvement on obtaining a better electromechanical coupling coefficient and controlling the frequency in design.
The preparation method comprises the following steps:
step S1: processing the silicon substrate 20 by an RCA cleaning process, drying, etching a groove on the surface of the silicon substrate 20 by dry etching, and depositing a sacrificial layer at the groove; wherein the depth of the groove is 20 μm; the depositing a sacrificial layer at the groove comprises: depositing a loose SiO2 layer on the SiO2 layer by a PECVD method;
step S2: depositing a phenylene-based bottom electrode layer 40 material on the silicon substrate 20; in step S2, the method further includes:
adding a trifluoromethanesulfonylation reagent into o-iodophenol, reacting the obtained product with a lithium reagent in a low-temperature solvent to prepare a biphenylene group, and then obtaining a biphenylene group bottom electrode layer 40 material in a vapor deposition mode;
and step S3: bonding a piezoelectric layer 50 material, and etching the piezoelectric layer 50 to form a required pattern; in step S3, the method further includes:
step S31: depositing a piezoelectric material film on a silicon substrate 20 by magnetron sputtering, and then carrying out heat treatment and inert gas protection treatment on the piezoelectric material film;
step S32: further growing the piezoelectric material with high crystal quality on the piezoelectric material film processed in the step S31 by an organic metal compound chemical vapor deposition method, and then etching and stripping to remove the part except the piezoelectric material film so as to obtain the piezoelectric material;
and step S4: depositing a top electrode layer 60 material and etching it to obtain a pattern;
step S5: and obtaining a release window around the cavity 30 by dry etching, injecting corrosive solution into the release window, removing the loose sacrificial layer, and forming an air cavity, thereby obtaining the film cavity acoustic wave resonator.
Further, the horizontal areas of the bottom electrode layer 40 and the top electrode layer 60 are smaller than the horizontal area of the silicon substrate 20, and the bottom electrode layer 40 and the top electrode layer 60 respectively extend from two ends of the piezoelectric layer 50 and completely cover the cavity 30.
In the present embodiment, an inclination angle of 70 ° to 86 ° is provided between the inner sidewall of the cavity 30 and the bottom surface of the cavity 30. Since a sacrificial layer (a so-called sacrificial layer is a SiO2 layer deposited on a SiO2 layer by a PECVD method) needs to be filled and released in the cavity 30, an inclination angle is provided at an inner sidewall of the cavity 30.
In the present embodiment, the piezoelectric layer 50 includes at least one piezoelectric material of AlN, znO, PTZ. Further, the top electrode layer 60 is composed of at least one of a biphenylene group, gold, copper, silver, aluminum, tungsten, platinum, molybdenum, rhodium, iridium, and titanium. Further, the film bulk acoustic resonator includes a support base 10, and the silicon substrate 20 is disposed on the support base 10.
Referring to fig. 3, a specific embodiment of the method for manufacturing a film bulk acoustic resonator includes the following steps:
1) Processing the silicon wafer (silicon substrate 20) by using a standard RCA cleaning process, and then drying;
2) Etching a groove on the surface of the silicon wafer by dry etching, wherein the depth of the groove is 20 mu m;
3) Depositing a SiO2 layer on the surface of the silicon wafer through thermal oxidation growth;
4) Depositing a loose SiO2 layer (as a sacrificial layer) on the SiO2 layer by a PECVD method;
5) Carrying out Chemical Mechanical Polishing (CMP), removing the SiO2 layer higher than the edge of the groove, and then cleaning;
6) Evaporating and depositing a material of the bottom electrode layer 40 of the phenylene and etching a bottom electrode pattern;
7) Bonding the piezoelectric layer 50 material, and etching the piezoelectric layer 50 to form a required pattern;
8) Depositing a top electrode layer 60 material and etching it to obtain a pattern;
9) And obtaining a release window around the cavity 30 by dry etching, injecting HF solution from the release window, removing the loose SiO2 layer, and forming an air cavity, thereby obtaining the film cavity acoustic wave resonator.
It should be noted that:
1. the standard RCA cleaning process was pioneered in 1965 by Kern and Puotinen et al in the RCA laboratory of n.j. RCA is a typical, and by far the most commonly used, wet chemical cleaning process that consists essentially of the following cleaning solutions. (1) SPM H2SO4/H2O2 SPM has high oxidation capacity at 120-150 ℃, can oxidize metals and dissolve the metals into cleaning liquid, and can oxidize organic matters to generate CO 2 and H2O. Cleaning the wafers with SPM removes heavy organic contaminants and some metals from the wafer surfaces, but when organic contaminants are particularly severe, they carbonize the organics and are difficult to remove. (2) HF (DHF) DHF at 20-25 deg.C removes the native oxide film on the silicon wafer surface, so that the metal adhered to the native oxide film is dissolved in the cleaning solution and the formation of oxide film is inhibited by DHF. Therefore, al, fe, zn, ni and other metals on the surface of the silicon wafer can be easily removed, and DHF can also remove metal hydroxides attached to the natural oxide film. When the native oxide film is etched away in cleaning with DHF, silicon on the surface of the silicon wafer is hardly etched. (3) APM (SC-1) NH4OH/H2O2/H2O is used for forming a layer of natural oxide film (SiO 2) on the surface of the silicon wafer at the temperature of 30-80 ℃ under the action of H2O2, the silicon wafer is hydrophilic, and the surface of the silicon wafer and the particles can be soaked by cleaning solution. Because the natural oxide layer on the surface of the silicon wafer and the Si on the surface of the silicon wafer are corroded by NH4OH, particles attached to the surface of the silicon wafer fall into the cleaning solution, and the purpose of removing the particles is achieved. And when the NH4OH corrodes the surface of the silicon wafer, the H2O2 forms a new oxide film on the surface of the silicon wafer. (4) HPM (SC-2) HCl/H2O 2/H2O is used for removing metal contamination of sodium, iron, magnesium and the like on the surface of the silicon wafer at the temperature of 65-85 ℃. HPM removes Fe and Zn at room temperature. The general idea of cleaning is to remove organic contaminants on the surface of the silicon wafer first, because organic substances cover part of the surface of the silicon wafer, thereby making the oxide film and the contaminants related thereto difficult to remove; the oxide film is then dissolved, since the oxide layer is a "contamination trap", epitaxial defects are also introduced; finally removing contamination such as particles, metal and the like, and simultaneously passivating the surface of the silicon wafer.
2. Dry etching is a technique of performing thin film etching using plasma. When the gas exists in the form of plasma, the plasma etching method has the two characteristics that on one hand, the chemical activity of the gas in the plasma is much stronger than that of the gas in a normal state, and the gas can react with the material more quickly by selecting proper gas according to the difference of the etched material, so that the aim of etching removal is fulfilled; on the other hand, the electric field can be used for guiding and accelerating the plasma, so that the plasma has certain energy, and when the plasma bombards the surface of the etched object, atoms of the etched object material can be knocked out, thereby achieving the purpose of etching by utilizing physical energy transfer. Thus, dry etching is a result of a balance of both physical and chemical processes on the wafer surface.
The pecvd method is a method of forming a plasma locally by ionizing a gas containing atoms of a film component by means of microwave or radio frequency, etc., and the plasma is chemically very reactive and easily reacts to deposit a desired film on a substrate. In order to allow chemical reactions to proceed at lower temperatures, the reactivity of the plasma is exploited to promote the reactions, and thus such CVD is known as Plasma Enhanced Chemical Vapor Deposition (PECVD). The experimental mechanism is that gas containing film composition atoms forms plasma locally by means of microwave or radio frequency, and the plasma has strong chemical activity and is easy to react to deposit the expected film on the substrate. The advantages are as follows: the basic temperature is low; the deposition rate is high; good film forming quality, less pinholes and difficult cracking.
4. Vapor deposition is a process in which a substance to be formed into a film is evaporated or sublimated in a vacuum to be precipitated on the surface of a workpiece or a substrate.
A film bulk acoustic resonator is manufactured by executing the manufacturing method of the film bulk acoustic resonator.
The invention has the beneficial effects that: 1. the thickness of the electrode layer is greatly reduced, the thickness of the electrode layer can be effectively ignored, and the actual working frequency of the device can be accurately calculated and predicted in the design. 2. The continuous diphenylene material is used as the electrode layer, and the continuous diphenylene has better conductivity than graphene, so that the Q value of the film cavity acoustic wave resonator can be effectively increased, the efficiency of the device is improved, and the power capacity can be increased.
The above embodiments are only for describing the preferred embodiments of the present invention, and are not intended to limit the scope of the present invention, and various modifications and improvements made to the technical solution of the present invention by those skilled in the art without departing from the spirit of the design of the present invention should fall within the protection scope defined by the claims of the present invention.
Claims (10)
1. A method for preparing a film cavity acoustic wave resonator is characterized in that the film cavity acoustic wave resonator comprises the following steps: the piezoelectric sensor comprises a silicon substrate, a bottom electrode layer, a piezoelectric layer and a top electrode layer which are sequentially arranged from bottom to top, wherein a cavity which is sunken downwards is formed in the top surface of the silicon substrate, and the bottom electrode layer is a bottom electrode layer of a phenylene group;
the preparation method comprises the following steps:
step S1: processing the silicon substrate by an RCA cleaning process, drying, etching a groove on the surface of the silicon substrate by a dry method, and depositing a sacrificial layer at the groove;
step S2: depositing a material of a phenylene bottom electrode layer on the silicon substrate;
and step S3: bonding piezoelectric layer materials, and etching the piezoelectric layer to form a required pattern;
and step S4: depositing a top electrode layer material, and etching the top electrode layer material to obtain a pattern;
step S5: and obtaining a release window around the cavity through dry etching, injecting corrosive solution into the release window, removing the loose sacrificial layer, and forming an air cavity to obtain the film cavity acoustic wave resonator.
2. The method for manufacturing a thin film bulk acoustic resonator according to claim 1, characterized in that: the depositing a sacrificial layer at the groove comprises: a loose SiO2 layer is deposited on the SiO2 layer by PECVD.
3. The method for manufacturing a film bulk acoustic resonator according to claim 1, wherein: in step S2, the method further includes:
adding a trifluoromethanesulfonylation reagent into o-iodophenol, reacting the obtained product with a lithium reagent in a low-temperature solvent to prepare a biphenylene group, and then obtaining a biphenylene group bottom electrode layer material in a vapor deposition mode.
4. The method for manufacturing a thin film bulk acoustic resonator according to claim 1, characterized in that: in step S3, the method further includes:
step S31: depositing a piezoelectric material film on a silicon substrate through magnetron sputtering, and then carrying out heat treatment and inert gas protection treatment on the piezoelectric material film;
step S32: and (3) further growing the piezoelectric material with high crystal quality on the piezoelectric material film processed in the step (S31) by an organic metal compound chemical vapor deposition method, and then etching and stripping to remove the part except the piezoelectric material film so as to obtain the piezoelectric material.
5. The method for manufacturing a film bulk acoustic resonator according to claim 1, wherein: the horizontal areas of the bottom electrode layer and the top electrode layer are smaller than the horizontal area of the silicon substrate, and the bottom electrode layer and the top electrode layer extend from two ends of the piezoelectric layer respectively and completely cover the cavity.
6. The method for manufacturing a thin film bulk acoustic resonator according to claim 1, characterized in that: an inclination angle of 70-86 degrees is arranged between the inner side wall of the cavity and the bottom surface of the cavity.
7. The method for manufacturing a thin film bulk acoustic resonator according to claim 1, characterized in that: the piezoelectric layer comprises at least one piezoelectric material of AlN, znO and PTZ.
8. The method for manufacturing a thin film bulk acoustic resonator according to claim 1, characterized in that: the top electrode layer is composed of at least one of a phenylene group, gold, copper, silver, aluminum, tungsten, platinum, molybdenum, rhodium, iridium and titanium.
9. The method for manufacturing a thin film bulk acoustic resonator according to claim 1, characterized in that: the film cavity acoustic wave resonator comprises a supporting base, and the silicon substrate is arranged on the supporting base.
10. A thin film bulk acoustic resonator, characterized in that the thin film bulk acoustic resonator is manufactured by performing the manufacturing method of the thin film bulk acoustic resonator according to any one of claims 1 to 9.
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| CN202210752612.0A CN115333497A (en) | 2022-06-28 | 2022-06-28 | Preparation method of film cavity acoustic wave resonator and film cavity acoustic wave resonator |
| PCT/CN2022/140678 WO2024001087A1 (en) | 2022-06-28 | 2022-12-21 | Preparation method for film bulk acoustic resonator, and film bulk acoustic resonator |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116248062A (en) * | 2023-01-10 | 2023-06-09 | 武汉敏声新技术有限公司 | Bulk acoustic wave resonator and preparation method thereof |
| WO2024001087A1 (en) * | 2022-06-28 | 2024-01-04 | 广州市艾佛光通科技有限公司 | Preparation method for film bulk acoustic resonator, and film bulk acoustic resonator |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN103873010B (en) * | 2014-03-17 | 2017-03-22 | 电子科技大学 | Piezoelectric film bulk acoustic resonator and preparation method thereof |
| US11555128B2 (en) * | 2015-11-12 | 2023-01-17 | Guangzhou Chinaray Optoelectronic Materials Ltd. | Printing composition, electronic device comprising same and preparation method for functional material thin film |
| CN109951171B (en) * | 2019-03-26 | 2023-09-01 | 浙江华远微电科技有限公司 | Method for preparing film bulk acoustic resonator and filter |
| CN112532195B (en) * | 2020-12-02 | 2021-11-12 | 海宁波恩斯坦生物科技有限公司 | Passive cavity type single crystal film bulk acoustic resonator structure and preparation method thereof |
| CN115333497A (en) * | 2022-06-28 | 2022-11-11 | 广州市艾佛光通科技有限公司 | Preparation method of film cavity acoustic wave resonator and film cavity acoustic wave resonator |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2024001087A1 (en) * | 2022-06-28 | 2024-01-04 | 广州市艾佛光通科技有限公司 | Preparation method for film bulk acoustic resonator, and film bulk acoustic resonator |
| CN116248062A (en) * | 2023-01-10 | 2023-06-09 | 武汉敏声新技术有限公司 | Bulk acoustic wave resonator and preparation method thereof |
| CN116248062B (en) * | 2023-01-10 | 2024-04-02 | 武汉敏声新技术有限公司 | Bulk acoustic wave resonator and preparation method thereof |
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