CN111010136A - Film cavity acoustic resonator and preparation method thereof - Google Patents
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- 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
-
- 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
- H03H9/178—Constructional features of resonators consisting of piezoelectric or electrostrictive material having a single resonator of a laminated structure of multiple piezoelectric layers with inner electrodes
-
- 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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- 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 film chamber acoustic resonator and a preparation method thereof, wherein the resonator comprises: the silicon substrate is provided with a cavity; the electrode layer comprises a first electrode layer and a second electrode layer, the first electrode layer is a graphene film, the first electrode layer and the second electrode layer are sequentially arranged above the silicon substrate, the horizontal areas of the first electrode layer and the second electrode layer are smaller than that of the silicon substrate, and orthographic projections of the first electrode layer and the second electrode layer on a horizontal plane are only overlapped at the cavity; and the piezoelectric layer is arranged between the first electrode layer and the second electrode layer. According to the invention, the graphene film is used as the electrode layer, the thickness of the electrode is reduced, the Q value and the effective electromechanical coupling coefficient of the resonator can be improved, and thus the signal conversion efficiency is improved.
Description
Technical Field
The invention relates to the field of film cavity acoustic resonance, in particular to a film cavity acoustic resonator and a preparation method thereof.
Background
With the arrival of 5G, new frequency bands applied to 5G are added, and these frequency bands are high frequency ends, namely n41, n78 and n79, respectively, and the lowest n41 application frequency is also 2496MHz, more than 2GHz and near 2.5GHz, at this time, the common SAW filter is difficult to meet the frequency application, so that the FBAR filter is the best solution at present.
FBAR (film bulk acoustic resonator) is a structured component having a piezoelectric effect material and being capable of forming an (inverse) piezoelectric effect structure. The working principle of the FBAR is as follows: in the stacked core structure composed of the electrode, the piezoelectric material and the electrode, the piezoelectric material is deformed by applying voltage to the electrode; when an alternating voltage is applied, the structure produces a piezoelectric effect. In the process, the electric energy is converted into mechanical energy, the mechanical energy is transmitted in the structure through sound waves, and the vibration can generate an electric signal while causing vibration, namely the mechanical energy is converted into an electric energy signal through an inverse piezoelectric effect to be output. The piezoelectric effect and the inverse piezoelectric effect exist at the same time, interact with each other and can generate resonance in the interaction process, so that the signal is selected.
The FBARs may form a filtering effect, i.e., an FBAR filter, by cascading. The FBAR filter has the advantages of low insertion loss, high frequency selectivity and the like, but the electrode of the conventional FBAR device has a certain thickness, which is equivalent to prolonging the acoustic path, so that frequency deviation is caused; and the resistance and thickness of the conventional electrode material are also related, so that some uncertain variables are added in the design, which makes the design difficult.
Secondly, for the current FBAR, the Q value and kt2 (effective electromechanical coupling coefficient) are two keys, but to a certain extent, the Q value and kt2 have mutual constraints, and when the Q value is increased, kt2 is decreased, and if the kt2 is increased, the Q value is sacrificed, so that the transmission characteristic of the resonator cannot be improved.
Disclosure of Invention
In order to overcome the defects of the prior art, one of the objectives of the present invention is to provide a film bulk acoustic resonator, which uses a graphene film as an electrode layer, reduces the thickness of the electrode, and can improve the Q value and the effective electromechanical coupling coefficient of the resonator, thereby improving the signal conversion efficiency.
The second objective of the present invention is to provide a method for manufacturing a film bulk acoustic resonator.
One of the purposes of the invention is realized by adopting the following technical scheme:
a film bulk acoustic resonator comprising:
the silicon substrate is provided with a cavity;
the electrode layer comprises a first electrode layer and a second electrode layer, the first electrode layer is a graphene film, the first electrode layer and the second electrode layer are sequentially arranged above the silicon substrate, the horizontal areas of the first electrode layer and the second electrode layer are smaller than that of the silicon substrate, and orthographic projections of the first electrode layer and the second electrode layer on a horizontal plane are only overlapped at the cavity;
and the piezoelectric layer is arranged between the first electrode layer and the second electrode layer.
Furthermore, an inclination angle of 80-88 degrees is arranged between the inner side wall of the cavity and the bottom surface of the cavity.
Furthermore, a plurality of slots are formed in the periphery of the cavity, each slot extends upwards and penetrates through the piezoelectric layer, and the slots are exposed out of the piezoelectric layer and communicated with the outside atmosphere.
Further, the first electrode layer and the second electrode layer extend from both ends of the piezoelectric layer and completely cover right above the cavity, respectively.
Further, the horizontal area of the first electrode layer is larger than that of the second electrode layer.
Further, the second electrode layer is a graphene film or a metal layer.
The second purpose of the invention is realized by adopting the following technical scheme:
a method for preparing a film cavity acoustic resonator is used for preparing the film cavity acoustic resonator, and comprises the following steps:
step S1: selecting a monocrystalline silicon wafer as a silicon substrate, carrying out plasma etching on the silicon wafer to form a cavity, and filling a sacrificial layer in the cavity;
step S2: growing a first electrode layer made of graphene on the silicon substrate, wherein the horizontal area of the first electrode layer is smaller than that of the silicon substrate, and the first electrode layer is covered right above the cavity;
step S3: a piezoelectric layer made of aluminum nitride grows on the first electrode layer in a clinging mode, so that the piezoelectric layer completely covers the first electrode layer and the silicon substrate;
step S4: a second electrode layer grows on the piezoelectric layer in a clinging mode, the horizontal area of the second electrode layer is smaller than that of the piezoelectric layer, and orthographic projections of the first electrode layer and the second electrode layer on the horizontal plane are only overlapped at the cavity;
step S5: and releasing the sacrificial layer.
Further, the preparation method of the first electrode layer made of graphene in step S2 includes: selecting a metal substrate, introducing hydrocarbon during the heating process of the metal substrate, enabling the hydrocarbon and the metal substrate to continuously react under a heating environment, and obtaining single-layer or more than single-layer graphene on the surface of the metal substrate during the cooling process of the metal substrate after the reaction is finished to form a first electrode layer.
Further, the method for preparing the piezoelectric layer in step S3 includes: an aluminum target is set up in a PVD apparatus, a mixture gas comprising nitrogen is introduced, and aluminum nitride is finally grown on the wafer by bombarding the aluminum target.
Further, the step S3, after the piezoelectric layer is grown, further includes performing quality inspection on the piezoelectric layer, and performing subsequent steps after the piezoelectric layer is detected to be qualified.
Compared with the prior art, the invention has the beneficial effects that:
the graphene film is used as an electrode, the processing of an acoustic propagation path can be simplified, and the actual working frequency can be accurately predicted; meanwhile, the graphene has excellent electrical conductivity and thermal conductivity, so that the Q value of the FBAR can be improved, and the power capacity can be increased; in addition, the graphene material has good adhesion and toughness, the self loss is small, and the efficiency can be improved in signal conversion, so that the FBAR can have a better effective electromechanical coupling coefficient.
Drawings
FIG. 1 is a schematic side view of a film bulk acoustic resonator according to the present invention;
FIG. 2 is a schematic top view of a film bulk acoustic resonator of the present invention;
FIG. 3 is a schematic flow chart of a method for manufacturing a film bulk acoustic resonator according to the present invention.
In the figure: 101. a silicon substrate; 102. a cavity; 103. a first electrode layer; 104. a piezoelectric layer; 105. a second electrode layer; 106. and (4) slotting.
Detailed Description
The present invention will be further described with reference to the accompanying drawings and the detailed description, and it should be noted that any combination of the embodiments or technical features described below can be used to form a new embodiment without conflict.
In this embodiment, as shown in fig. 1 and 2, a silicon substrate 101 is provided, the silicon substrate 101 is made of high-resistance silicon, the resistivity of the silicon substrate 101 is more than 10000 Ω, and silicon is used as a substrate of an FBAR, so that on one hand, silicon materials are mature in the prior art, and on the other hand, the silicon materials have many advantages in terms of process. However, the silicon may contain other impurities or other reasons, and if the resistivity is not high, part of energy is coupled into the silicon, so that the Q value is reduced, and therefore, the substrate silicon is high-resistance silicon.
The surface of the silicon substrate 101 is etched to form a cavity 102, on one hand, the reserved space enables the electrode layer to vibrate, and on the other hand, a sound wave propagation interface is formed, so that sound waves are totally reflected and do not leak and propagate outwards. In the present embodiment, the cavity 102 needs to be filled with and released from a sacrificial layer, so that the inner sidewall of the cavity 102 is provided with an inclination angle, that is, the inclination angle between the inner sidewall of the cavity 102 and the bottom surface of the cavity 102 is 80 ° to 88 °.
Meanwhile, in order to accelerate the release of the subsequent sacrificial layer, a plurality of slots 106 are formed around the cavity 102, each slot 106 extends upwards and penetrates through the piezoelectric layer 104, so that the slots 106 are exposed out of the piezoelectric layer 104 and communicated with the outside atmosphere; a slot 106 may also be provided in the first electrode so that the cavity 102 may communicate directly with the outside atmosphere through the first electrode and the piezoelectric layer 104. The slot 106 may be etched by using a through hole, and when the sacrificial layer needs to be released subsequently, the resonator is entirely immersed in acetone and a diluted hydrofluoric acid solution, and the solution enters the cavity 102 along the slot 106 during the immersion process to corrode the sacrificial layer, so as to remove the sacrificial layer in the cavity 102 and reduce the structure of the cavity 102.
Above the cavity 102 is the FBAR's effective resonance region, and to form the FBAR there is a critical structure, a first electrode, a second electrode, and a piezoelectric layer 104 sandwiched by the first and second electrodes. Acoustic waves of a certain frequency are excited in the piezoelectric layer 104, and form an acoustic wave propagation path together with the electrode layer, which is represented by the piezoelectric effect, and when mechanical energy is converted into electric energy, a conductor is required to transmit a signal, and thus an electrode is required.
The electrode layers comprise a first electrode layer 103 and a second electrode layer 105, the first electrode layer 103 is a graphene film, the graphene material has excellent electrical conductivity, very good thermal conductivity, and is strong and tough, and can be used as an FBAR electrode, so that a good Q value can be obtained, the graphene material can be made very thin, the better kt2 can be obtained, the control of the frequency in the design can be greatly improved, the thermal conductivity is excellent, and the improvement of the power utilization is greatly facilitated.
The first electrode layer 103 and the second electrode layer 105 are sequentially arranged above the silicon substrate 101, and a piezoelectric layer 104 is arranged between the first electrode layer 103 and the second electrode layer 105. The horizontal area of the piezoelectric layer 104 is the same as that of the silicon substrate 101, and the horizontal areas of the first electrode layer 103 and the second electrode layer 105 are both smaller than that of the piezoelectric layer 104; in this embodiment, the first electrode layer 103 starts from the left side of the lower surface of the piezoelectric layer 104 and extends to completely cover the cavity 102, and the second electrode layer 105 starts from the right side of the upper surface of the piezoelectric layer 104 and extends to completely block the cavity 102, so that orthographic projections of the first electrode layer 103 and the second electrode layer 105 on a horizontal plane are only overlapped at the cavity 102, that is, only the electrode-piezoelectric layer 104-electrode lamination structure of the FBAR effective resonance area directly above the cavity 102 is complete, and at a position outside the cavity 102, the electrode-piezoelectric layer 104-electrode lamination structure is incomplete, so that the FBAR effective resonance area is not in contact with the silicon substrate 101, and the operation characteristic is maintained.
The piezoelectric layer 104 has a piezoelectric effect, and there is a mutual conversion between mechanical energy and electrical energy, where the mechanical behavior is vibration, that is, the piezoelectric layer 104 is included, and the first and second electrodes that hold the piezoelectric layer 104 vibrate along the Z-axis, so as to ensure the piezoelectric effect. In this embodiment, the horizontal area of the first electrode layer 103 is larger than the horizontal area of the second electrode layer 105, and the horizontal centerline extension line of the first electrode layer 103 and the horizontal centerline extension line of the second electrode layer 105 are on the same horizontal straight line, so that the process of mechanical vibration is relatively stable.
In this embodiment, the resonator is provided with a substrate silicon and a graphene film layer covering a region on which the patterned cavity 102 is etched from bottom to top, and then the first electrode is attached to the long upper piezoelectric layer 104, and the piezoelectric layer 104 is attached to a second electrode, so as to form a stacked structure of the electrode, the piezoelectric layer 104 and the electrode. The second electrode layer 105 may be a graphene thin film having the same structure as the first electrode layer 103, and a metal layer formed by combining various metal materials such as Mo, Pt, and Al may be used.
The invention discloses a novel FBAR of a membrane electrode, which has the following advantages:
1. the thin electrode can simplify the processing of the acoustic propagation path, and can accurately predict the actual working frequency in the design.
2. The graphene film layer is used as an electrode, and the graphene has excellent electrical conductivity and thermal conductivity, so that the Q value of the FBAR can be improved, and meanwhile, the power capacity is also increased.
3. The graphene material has good adhesion and toughness, the loss of the graphene material is small, and the efficiency can be improved in signal conversion, so that the FBAR can have a better effective electromechanical coupling coefficient.
Example two
A method for manufacturing a film bulk acoustic resonator, which is used to manufacture the film bulk acoustic resonator in the first embodiment, as shown in fig. 3, includes the following steps:
step S1: a monocrystalline silicon wafer is selected as a silicon substrate 101, plasma etching is carried out on the silicon wafer to form a cavity 102, and a sacrificial layer is filled in the cavity 102.
The silicon substrate 101 is made of a high-impedance monocrystalline wafer, so that a monocrystalline phase of the silicon wafer can be ensured, and the grown piezoelectric layer 104 has a relatively good single orientation, generally in the longitudinal direction. And the high-impedance silicon chip can reduce the coupling effect on the FBAR. After the wafer is cleaned, or a mark needs to be added, glue spreading, exposure, development and the like are carried out, plasma etching is carried out, and a cavity 102 is etched on the wafer.
Wherein the cavity 102 is filled with a sacrificial layer and then the cavity 102 is temporarily filled up by chemical mechanical polishing or the like. The inner sidewall of the cavity 102 is not completely vertical, and considering that the conventional process requires a release material to be filled, an adhesion inclination angle is required, and it is preferable that an angle between the inner sidewall of the cavity 102 and the bottom surface of the cavity 102 is 80 to 88 °.
Step S2: growing a first electrode layer 103 made of graphene on the silicon substrate 101, wherein the horizontal area of the first electrode layer 103 is smaller than that of the silicon substrate 101, and the first electrode layer 103 is covered right above the cavity 102.
The graphene first electrode layer 103 is preferably grown by chemical vapor deposition. Introducing hydrocarbon such as methane and ethanol into the surface of Cu and Ni of a metal substrate heated at high temperature, reacting for a certain time, cooling, and forming a plurality of layers or single-layer graphene on the surface of the substrate in the cooling process, wherein the process comprises two parts of dissolution and diffusion growth of carbon atoms on the substrate.
Thereafter, the graphene is processed again by dry etching to obtain a desired pattern, thereby forming the first electrode layer 103. The first electrode layer 103 is covered on the silicon substrate 101, and a state of completely covering the cavity 102 is maintained.
Step S3: a piezoelectric layer 104 made of aluminum nitride is grown on the first electrode layer 103, such that the piezoelectric layer 104 completely covers the first electrode layer 103 and the silicon substrate 101.
The growth of piezoelectric layer 104, preferably by magnetron sputtering, i.e., PVD, enables the formation of piezoelectric layer 104 with low stress, controllable thickness and roughness. AlN is selected as a piezoelectric material, an aluminum target is assembled in PVD equipment, high-purity nitrogen with the purity of 99.999999 percent, namely nitrogen with the precision of at least 6 bits, and other gases such as argon are introduced, and the AlN is finally grown on the wafer by bombarding the aluminum target in work.
The piezoelectric layer 104 is important for FBAR performance, and therefore, the film quality of the piezoelectric layer 104 needs to be checked. The main items are the detection of the thickness distribution of a film on a wafer, the stress distribution on the wafer, the quality of crystals on the wafer and the like.
Step S4: a second electrode layer 105 is grown next to the piezoelectric layer 104, the horizontal area of the second electrode layer 105 is smaller than the horizontal area of the piezoelectric layer 104, and the orthographic projections of the first electrode layer 103 and the second electrode layer 105 on the horizontal plane are only overlapped at the cavity 102.
The second electrode layer 105 may also be a graphene electrode layer, which is prepared in the same way as the first electrode layer 103, and a conventional metal layer, such as an electrode layer made of molybdenum, may be used as the second electrode layer 105.
After the first electrode layer 103, the piezoelectric layer 104 and the second electrode layer 105 are prepared, a notch 106 is formed in the piezoelectric layer 104 without being covered by the second electrode layer 105, and the depth of the notch 106 extends from the upper top surface of the piezoelectric layer 104 to the cavity 102, so that the cavity 102 is communicated with the outside air and can penetrate through the first electrode layer 103 if necessary and is communicated with the cavity 102 all the time.
Step S5: and releasing the sacrificial layer.
The prepared resonator is placed in an acetone memory hydrofluoric acid solution for soaking, liquid permeates into the cavity 102 through the slot 106 to corrode the sacrificial layer in the cavity 102, and after the corrosion process is finished, the structure of the cavity 102 between the first electrode and the silicon substrate 101 below the first electrode is restored, so that on one hand, a space is reserved to enable the thin film layer stack to vibrate, on the other hand, a sound wave propagation interface is formed, sound waves are enabled to be totally reflected and not leaked and propagated outwards, and the working characteristics of the resonator are kept.
The above embodiments are only preferred embodiments of the present invention, and the protection scope of the present invention is not limited thereby, and any insubstantial changes and substitutions made by those skilled in the art based on the present invention are within the protection scope of the present invention.
Claims (10)
1. A film bulk acoustic resonator, comprising:
the silicon substrate is provided with a cavity;
the electrode layer comprises a first electrode layer and a second electrode layer, the first electrode layer is a graphene film, the first electrode layer and the second electrode layer are sequentially arranged above the silicon substrate, the horizontal areas of the first electrode layer and the second electrode layer are smaller than that of the silicon substrate, and orthographic projections of the first electrode layer and the second electrode layer on a horizontal plane are only overlapped at the cavity;
and the piezoelectric layer is arranged between the first electrode layer and the second electrode layer.
2. The film bulk acoustic resonator according to claim 1, wherein the inner sidewalls of the cavity each have an inclination of 80 ° to 88 ° with the bottom surface of the cavity.
3. The film bulk acoustic resonator of claim 2, wherein the cavity is surrounded by a plurality of slots, each slot extending upwardly through the piezoelectric layer such that the slot is exposed to the exterior of the piezoelectric layer and is open to the ambient atmosphere.
4. The film bulk acoustic resonator according to claim 1, wherein the first electrode layer and the second electrode layer extend from both ends of the piezoelectric layer and completely cover right above the cavity, respectively.
5. The film bulk acoustic resonator according to claim 4, wherein the horizontal area of the first electrode layer is larger than the horizontal area of the second electrode layer.
6. The film bulk acoustic resonator according to claim 4, wherein the second electrode layer is provided as a graphene film or a metal layer.
7. A method for manufacturing a film bulk acoustic resonator, which is used for manufacturing the film bulk acoustic resonator according to any one of claims 1 to 6, comprising the following steps:
step S1: selecting a monocrystalline silicon wafer as a silicon substrate, carrying out plasma etching on the silicon wafer to form a cavity, and filling a sacrificial layer in the cavity;
step S2: growing a first electrode layer made of graphene on the silicon substrate, wherein the horizontal area of the first electrode layer is smaller than that of the silicon substrate, and the first electrode layer is covered right above the cavity;
step S3: a piezoelectric layer made of aluminum nitride grows on the first electrode layer in a clinging mode, so that the piezoelectric layer completely covers the first electrode layer and the silicon substrate;
step S4: a second electrode layer grows on the piezoelectric layer in a clinging mode, the horizontal area of the second electrode layer is smaller than that of the piezoelectric layer, and orthographic projections of the first electrode layer and the second electrode layer on the horizontal plane are only overlapped at the cavity;
step S5: and releasing the sacrificial layer.
8. The method for preparing a film bulk acoustic resonator according to claim 7, wherein the step S2 is performed by preparing the first electrode layer made of graphene material by: selecting a metal substrate, introducing hydrocarbon during the heating process of the metal substrate, enabling the hydrocarbon and the metal substrate to continuously react under a heating environment, and obtaining single-layer or more than single-layer graphene on the surface of the metal substrate during the cooling process of the metal substrate after the reaction is finished to form a first electrode layer.
9. The method for manufacturing a thin film bulk acoustic resonator according to claim 7, wherein the method for manufacturing the piezoelectric layer in step S3 is: an aluminum target is set up in a PVD apparatus, a mixture gas comprising nitrogen is introduced, and aluminum nitride is finally grown on the wafer by bombarding the aluminum target.
10. The method for manufacturing a film bulk acoustic resonator according to claim 9, wherein the step S3, after growing the piezoelectric layer, further comprises quality inspection of the piezoelectric layer, and the subsequent steps are performed after the piezoelectric layer is qualified.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911338888.9A CN111010136A (en) | 2019-12-23 | 2019-12-23 | Film cavity acoustic resonator and preparation method thereof |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114094970A (en) * | 2022-01-20 | 2022-02-25 | 深圳新声半导体有限公司 | Method for manufacturing film bulk acoustic wave resonator and resonator |
| US11463070B2 (en) | 2022-01-18 | 2022-10-04 | Shenzhen Newsonic Technologies Co., Ltd. | FBAR structure and manufacturing method of same |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US11463070B2 (en) | 2022-01-18 | 2022-10-04 | Shenzhen Newsonic Technologies Co., Ltd. | FBAR structure and manufacturing method of same |
| CN114094970A (en) * | 2022-01-20 | 2022-02-25 | 深圳新声半导体有限公司 | Method for manufacturing film bulk acoustic wave resonator and resonator |
| CN114094970B (en) * | 2022-01-20 | 2022-05-17 | 深圳新声半导体有限公司 | Method for manufacturing film bulk acoustic wave resonator and resonator |
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