[go: up one dir, main page]
More Web Proxy on the site http://driver.im/

WO2019095640A1 - 压电谐振器和压电谐振器的制备方法 - Google Patents

压电谐振器和压电谐振器的制备方法 Download PDF

Info

Publication number
WO2019095640A1
WO2019095640A1 PCT/CN2018/085289 CN2018085289W WO2019095640A1 WO 2019095640 A1 WO2019095640 A1 WO 2019095640A1 CN 2018085289 W CN2018085289 W CN 2018085289W WO 2019095640 A1 WO2019095640 A1 WO 2019095640A1
Authority
WO
WIPO (PCT)
Prior art keywords
electrode
substrate
piezoelectric
layer
piezoelectric resonator
Prior art date
Application number
PCT/CN2018/085289
Other languages
English (en)
French (fr)
Inventor
左成杰
何军
Original Assignee
安徽云塔电子科技有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from CN201721512611.XU external-priority patent/CN207339804U/zh
Priority claimed from CN201711121168.8A external-priority patent/CN107733395A/zh
Application filed by 安徽云塔电子科技有限公司 filed Critical 安徽云塔电子科技有限公司
Priority to JP2020526508A priority Critical patent/JP2021503229A/ja
Priority to US16/754,169 priority patent/US20210211115A1/en
Priority to KR1020207010371A priority patent/KR20200052928A/ko
Publication of WO2019095640A1 publication Critical patent/WO2019095640A1/zh

Links

Images

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
    • H03H9/02535—Details of surface acoustic wave devices
    • H03H9/02543—Characteristics of substrate, e.g. cutting angles
    • H03H9/02574—Characteristics of substrate, e.g. cutting angles of combined substrates, multilayered substrates, piezoelectrical layers on not-piezoelectrical substrate
    • 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
    • H03H3/04—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 for obtaining desired frequency or temperature coefficient
    • 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
    • H03H9/02015—Characteristics of piezoelectric layers, e.g. cutting angles
    • 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
    • H03H9/02102—Means for compensation or elimination of undesirable effects of temperature influence
    • 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
    • H03H9/02228—Guided bulk acoustic wave devices or Lamb wave devices having interdigital transducers situated in parallel planes on either side of a piezoelectric layer
    • 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
    • H03H9/02535—Details of surface acoustic wave devices
    • H03H9/02818—Means for compensation or elimination of undesirable effects
    • H03H9/02834—Means for compensation or elimination of undesirable effects of temperature influence
    • 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
    • H03H9/125—Driving means, e.g. electrodes, coils
    • H03H9/13—Driving means, e.g. electrodes, coils for networks consisting of piezoelectric or electrostrictive materials
    • H03H9/132—Driving means, e.g. electrodes, coils for networks consisting of piezoelectric or electrostrictive materials characterized by a particular shape
    • 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
    • H03H9/172—Means for mounting on a substrate, i.e. means constituting the material interface confining the waves to a volume
    • H03H9/173—Air-gaps
    • 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
    • H03H9/172—Means for mounting on a substrate, i.e. means constituting the material interface confining the waves to a volume
    • H03H9/174—Membranes
    • 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
    • H03H2003/021—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 air-gap 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
    • H03H3/04—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 for obtaining desired frequency or temperature coefficient
    • H03H2003/0407—Temperature coefficient

Definitions

  • the embodiments of the present application relate to the technical field of acoustic wave resonators, for example, to a piezoelectric resonator and a method for preparing the piezoelectric resonator.
  • a surface acoustic wave device for example, a surface acoustic wave filter (SAW)
  • SAW surface acoustic wave filter
  • Q quality factor
  • TCF temperature coefficient of frequency
  • a piezoelectric resonator such as a SAW resonator
  • a piezoelectric resonator includes a substrate 1 and a high sound velocity layer 2 on the upper surface of the substrate 1. (aluminum nitride material), a low sound velocity layer 3 (silica material) located on a surface of the high sound velocity layer 2 away from the substrate 1, and a piezoelectric layer located on a surface of the low sound velocity layer 3 away from the side of the high sound velocity layer 2 4 (lithium niobate material), and an electrode 5 located on the surface of the piezoelectric layer 4 away from the side of the low sound velocity layer 3.
  • aluminum nitride material aluminum nitride material
  • a low sound velocity layer 3 silicon material located on a surface of the high sound velocity layer 2 away from the substrate 1
  • a piezoelectric layer located on a surface of the low sound velocity layer 3 away from the side of the high sound velocity layer 2 4 (lithium niobate
  • the method for preparing a piezoelectric resonator and a piezoelectric resonator provided by the embodiments of the present invention effectively avoids leakage of sound energy into the substrate, reduces the loss of acoustic energy in the substrate, and can obtain a high Q value.
  • the electric resonator is made and the resulting piezoelectric resonator has a lower frequency temperature coefficient.
  • the embodiment of the present application provides a piezoelectric resonator, including:
  • first piezoelectric layer covering an upper surface of the substrate and an opening of the recess such that the recess forms a cavity with the first piezoelectric layer
  • a first electrode and a temperature compensation layer are disposed on a side of the first piezoelectric layer away from the substrate, and the first electrode is on the substrate in a direction perpendicular to the substrate The projection is located in the area where the groove is located.
  • the embodiment of the present application further provides a method for preparing a piezoelectric resonator, including:
  • first electrode and a temperature compensation layer on a side of the first piezoelectric layer away from the substrate, wherein the first electrode is located at a direction of the groove in a direction perpendicular to the substrate region;
  • the sacrificial material is removed to form a cavity.
  • the technical solution provided by the embodiment of the present invention can form a cavity on the upper surface of the substrate to form a cavity with the first piezoelectric layer, so that the sound wave forms total reflection through the cavity layer, thereby effectively avoiding the acoustic energy. Leakage into the substrate reduces the loss of acoustic energy in the substrate, and a high Q piezoelectric resonator can be obtained; and the temperature compensation layer is provided to keep the piezoelectric resonator at a lower frequency temperature coefficient, which can be effective Improve temperature compensation efficiency.
  • the second electrode present in the cavity can expand the range of application of the piezoelectric resonator by interacting with the first electrode, while the piezoelectric resonator prepared on the sealed cavity can be smaller in volume.
  • FIG. 1 is a schematic cross-sectional view showing a piezoelectric resonator in the related art.
  • FIG. 2 is a schematic cross-sectional view of a piezoelectric resonator according to an embodiment.
  • FIG. 3 is a cross-sectional structural view of another piezoelectric resonator according to an embodiment.
  • FIG. 4 is a schematic cross-sectional view of another piezoelectric resonator according to an embodiment.
  • FIG. 5 is a schematic cross-sectional view of another piezoelectric resonator according to an embodiment.
  • FIG. 6 is a cross-sectional structural view of another piezoelectric resonator according to an embodiment.
  • FIG. 7 is a cross-sectional structural view of another piezoelectric resonator according to an embodiment.
  • FIG. 8 is a cross-sectional structural view of another piezoelectric resonator according to an embodiment.
  • FIG. 9 is a cross-sectional structural view of another piezoelectric resonator according to an embodiment.
  • FIG. 10 is a schematic flow chart of a method for fabricating a piezoelectric resonator according to an embodiment.
  • the embodiment of the present application provides a piezoelectric resonator, which is suitable for use in the field of communication technology.
  • 2 is a cross-sectional structural view of a piezoelectric resonator according to an embodiment of the present application. Referring to FIG.
  • the structure of the resonator includes a substrate 1 disposed in sequence, a first piezoelectric layer 4, a first electrode 5 and a temperature compensation layer 3, wherein the upper surface of the substrate 1 is formed with a recess 11;
  • the piezoelectric layer 4 covers the upper surface of the substrate 1 and the opening of the recess 11 to form a cavity 11 and the first piezoelectric layer 4; wherein the cross-sectional structure of the recess 11 may be rectangular or curved
  • the shape is not limited to a rectangle or an arc as long as it is possible to avoid the leakage of sound energy into the substrate to the greatest extent possible.
  • the first electrode 5 and the temperature compensation layer 3 are both disposed on a side of the first piezoelectric layer 4 away from the substrate 1, and the projection of the first electrode 5 on the substrate 1 is in a concave direction in a direction perpendicular to the substrate 1.
  • the region where the groove 11 is located, wherein the first electrode 5 disposed on the side of the first piezoelectric layer 4 away from the substrate 1 may be on the upper surface of the temperature compensation layer 3, or disposed on the first piezoelectric layer 4 away from the substrate 1
  • the first electrode 5 on one side may be disposed in the same layer as the temperature compensation layer 3.
  • the technical solution provided by the embodiment of the present application can form a cavity on the upper surface of the substrate to form a cavity between the groove and the first piezoelectric layer, thereby effectively preventing sound energy from leaking into the substrate and reducing sound energy.
  • the loss in the substrate can obtain a piezoelectric resonator of high Q value; and the temperature compensation layer is provided, so that the piezoelectric resonator maintains a lower frequency temperature coefficient, and the temperature compensation efficiency can be effectively improved.
  • the first electrode is located on a surface of the first piezoelectric layer away from the substrate, and the temperature compensation layer covers the first electrode.
  • the piezoelectric resonator includes a substrate 1, a first electrode 5, a first piezoelectric layer 4, and a temperature compensation layer 3.
  • the material of the substrate 1 may be silicon, and the substrate can be made to have a high sound velocity, and the resistivity thereof is about 1000 ⁇ cm or more.
  • the insertion loss of the filter can be reduced.
  • the first piezoelectric layer 4 covers the substrate 1 in which the recess 11 is formed to obtain a cavity structure, and the first electrode 5 is located on the upper surface of the first piezoelectric layer 4 away from the substrate 1 and covers the temperature compensation layer 3 First electrode 5.
  • the first electrode 5 may be an interdigital electrode and is evenly distributed on the upper surface of the first piezoelectric layer 4, and the material of the temperature compensation layer 3 is filled between adjacent electrodes in the interdigital electrode.
  • the interdigital electrodes can excite different sound waves in multiple modes.
  • the first piezoelectric layer 4 may be aluminum nitride (AIN), zinc oxide (ZnO), lithium niobate (LiNbO 3 ) or lithium niobate (LiTaO 3 ), etc., and the first piezoelectric layer 4 is generally a material having a negative temperature coefficient. That is, the speed of sound becomes smaller as the temperature increases, because the decrease in the transatomic force of the material leads to a decrease in the elastic constant of the material, thereby reducing the speed of sound.
  • the material of the temperature compensation layer may be a positive temperature coefficient material, for example, it may be silica SiO 2 , SiO 2 is a unique material, and its silicon-oxygen chain is stretched with increasing temperature, so its stiffness has a positive temperature.
  • SiO 2 The coefficient, the sound wave propagating in SiO 2 , exhibits a positive temperature coefficient of sound velocity. Therefore, SiO 2 is used to compensate for the frequency offset of the piezoelectric resonator due to temperature change, and a good temperature compensation can be achieved for the first piezoelectric layer 4. Further, SiO 2 may be a low sound velocity layer, and its thickness may be on the order of nanometers, which has little effect on the Q of the preparation of the resonator and the electromechanical coupling coefficient (k t 2 ).
  • the temperature compensation layer is located on a surface of the first piezoelectric layer away from the substrate, and the first electrode is located on a side of the temperature compensation layer away from the substrate. In an embodiment, the first electrode is located on a surface of the temperature compensation layer away from the substrate side. In an embodiment, the piezoelectric resonator may further include a second piezoelectric layer between the temperature compensation layer and the first electrode, the first electrode being located on a surface of the second piezoelectric layer away from the substrate.
  • the piezoelectric resonator includes a substrate 1, a first electrode 5, a first piezoelectric layer 4 and a temperature compensation layer 3, and the first electrode 5 is located on a side of the temperature compensation layer 3 away from the substrate 1, wherein The first electrode 5 is located on the upper surface of the temperature compensation layer 3 away from the substrate 1.
  • the first electrode 5 may be an interdigital electrode and uniformly distributed on the upper surface of the temperature compensation layer 3, and the first electrode 5 and the temperature compensation layer 3 are disposed in a compartment.
  • the material of the interdigital electrode may be a metal alloy such as aluminum Al or aluminum-copper AlCu, which functions to convert an electrical signal into an acoustic signal through an interdigital transducer.
  • the thickness of the electrode film of the interdigital electrode is about 50 nm to 200 nm, which can ensure that the resistivity of the electrode is small.
  • the interdigital electrodes generate or generate an electric field in the temperature compensation layer 3 and the first piezoelectric layer 4, thereby exciting or acquiring sound waves in the filter and the resonator-specific vibration mode.
  • the piezoelectric resonator includes a substrate 1, a first electrode 5, a first piezoelectric layer 4, a temperature compensation layer 3, and a second pressure between the temperature compensation layer 3 and the first electrode 5.
  • the electric layer 7, the first electrode 5 is located on the surface of the second piezoelectric layer 7 away from the substrate 1. Since the first piezoelectric layer 4 and the second piezoelectric layer 7 are generally negative temperature coefficient materials, and the temperature compensation layer 3 may be SiO 2 , it is found by mechanical calculation that the temperature compensation layer 3 is under pressure in a specific vibration mode. When the position of the electric resonator is in the middle position, the temperature compensation efficiency can reach a higher value.
  • the frequency coefficient of temperature (TCF) of a piezoelectric resonator is determined by the thickness of each layer structure and their relative position and action within the cavity.
  • TCF frequency coefficient of temperature
  • a thicker layer of SiO 2 needs to be deposited above or below the piezoelectric resonator to compensate for the drift of the resonant frequency of the piezoelectric resonator with temperature.
  • temperature compensation can be realized by preparing a thin temperature compensation layer (SiO 2 ), and the efficiency of temperature compensation is greatly improved.
  • the piezoelectric resonator may further include a second electrode located in the cavity and disposed on a surface of the first piezoelectric layer near the substrate side.
  • the piezoelectric resonator further includes a second electrode 6 located in the cavity and disposed on a surface of the first piezoelectric layer 4 near the substrate 1.
  • the first electrode 5 may be an interdigital electrode
  • the second electrode 6 may be a planar electrode; the transverse body is excited in the first piezoelectric layer 4 and the temperature compensation layer 3 by the interaction of the interdigitated electrode and the planar electrode.
  • the temperature compensation layer 3 is a non-piezoelectric material SiO 2 between the first electrode 5 and the second electrode 6, the temperature compensation layer 3 consumes a part of the voltage of the first piezoelectric layer 4 (such as AIN), so that the first The electric field strength on the piezoelectric layer 4 is lowered, which in turn causes the electromechanical coupling coefficient k t 2 to decrease, and the lower effective electromechanical coupling coefficient is applied to the narrow band filter.
  • the first piezoelectric layer 4 such as AIN
  • the piezoelectric resonator further includes at least one of the following: the first electrode is an interdigital electrode or a planar electrode, and the second electrode is an interdigital electrode or a planar electrode.
  • the shape and arrangement position of at least one of the first electrode and the second electrode may be variously changed, and are not limited to the above cases, and the shape and position of at least one of the first electrode and the second electrode may be different.
  • the wave of the mode expands the range of applications of the piezoelectric resonator.
  • the second electrode 6 is an interdigital electrode and is disposed on a surface of the first piezoelectric layer 4 on the side close to the substrate 1.
  • the first electrode 5 may be an interdigital electrode located on the upper surface of the temperature compensation layer 3 on the side away from the substrate 1.
  • the second electrode 6 is an interdigital electrode and is disposed on a surface of the first piezoelectric layer 4 near the substrate 1.
  • the first electrode 5 may be an interdigital electrode located on a surface of the first piezoelectric layer 4 away from the substrate 1 and the temperature compensation layer 3 covers the first electrode 5.
  • the interdigital electrode can convert the electrical signal into an acoustic signal
  • the first electrode 5 and the second electrode 6 are both interdigital electrodes, and the first electrode 5 and the second electrode 6 cooperate with each other, and the piezoelectric device can be excited according to different circuit connection manners.
  • the resonator produces transverse body waves, longitudinal body waves or other forms of sound waves, and transverse body waves are generally suitable for narrow-band filters.
  • the second electrode 6 is a planar electrode and is disposed on a surface of the first piezoelectric layer 4 on the side close to the substrate 1.
  • the first electrode 5 may be an interdigital electrode located on a surface of the first piezoelectric layer 4 away from the substrate 1 and the temperature compensation layer 3 covers the first electrode 5.
  • the interdigital electrode can convert an electrical signal into an acoustic signal, and a transverse body wave can be excited by cooperating with the planar electrode.
  • the second electrode 6 is a planar electrode and is disposed on a surface of the first piezoelectric layer 4 near the substrate 1.
  • the first electrode 5 is a planar electrode disposed on the upper surface of the second piezoelectric layer 7 away from the substrate 1, and a temperature compensation layer 3 is disposed between the first piezoelectric layer 4 and the second piezoelectric layer 7.
  • the second electrode 6 is a planar electrode and is disposed on a surface of the first piezoelectric layer 4 near the substrate 1.
  • the first electrode 5 may be a planar electrode located on a surface of the first piezoelectric layer 4 away from the substrate 1 and the temperature compensation layer 3 covers the first electrode 5.
  • the two planar electrodes can excite longitudinal bulk waves and can be used in mobile communication systems.
  • the second electrode 6 is a planar electrode and is disposed on a surface of the first piezoelectric layer 4 near the substrate 1.
  • the first electrode 5 may be a planar electrode located on the upper surface of the temperature compensation layer 3 on the side away from the substrate 1.
  • the first electrode 5 is a planar electrode
  • the second electrode 6 is located at a position in the cavity, wherein the second electrode 6 may be a planar electrode; the first electrode 5 and the second electrode 6
  • the surface of the first piezoelectric layer 4 is similar to the film bulk acoustic resonator (FBAR) structure, and it is relatively easy to control the generation of the spurious mode and reduce the pair.
  • FBAR film bulk acoustic resonator
  • the influence of the Q and k t 2 of the piezoelectric resonator can be applied to the bulk material by applying a pair of planar electrodes to excite the longitudinal bulk wave in the piezoelectric material.
  • a temperature compensation layer (SiO 2 ) is generally deposited at the uppermost portion of the piezoelectric resonator, and has a double layer function, one of which can function as a temperature compensation; and second, the layer of SiO 2 It can be used as a protective layer to prevent the piezoelectric resonator from being contaminated by external water vapor, particles and the like.
  • the standard thickness of the SiO 2 layer should be less than half of the thickness of the first piezoelectric layer. If good harmonic characteristics and good temperature compensation characteristics are desired, the thickness of the SiO 2 layer can also be increased to 1.5 times the thickness of the first piezoelectric layer.
  • a temperature compensation layer SiO 2
  • SiO 2 a temperature compensation layer
  • This structure can maintain the piezoelectric resonator with a high Q value and a low frequency temperature coefficient (TCF), especially for application.
  • TCF temperature coefficient
  • a slight frequency drift due to temperature changes may cause the filter to not meet the specifications in the roll-off area.
  • it can also be applied to systems that solve interference between different communication standards, such as mobile phone systems that integrate satellite radio or GPS navigation.
  • FIG. 10 is a schematic flowchart of a method for preparing a piezoelectric resonator according to an embodiment of the present application, including:
  • Step 110 forming a groove on the upper surface of the substrate.
  • the substrate serves as a support layer, and the support layer may be a silicon substrate.
  • the silicon substrate On the silicon substrate, a portion of the silicon material may be removed by masking or photolithography on the support layer by a deep reactive ion etching process (DRIE).
  • DRIE deep reactive ion etching process
  • the structure may be rectangular or curved, and the depth of the cross-sectional structure of the groove may be on the order of nanometer or micrometer, and the size of the groove may be appropriately selected according to actual needs.
  • the silicon substrate may be a layer of high sound velocity material, and its resistivity may be 1000 ⁇ cm or more, which can reduce the insertion loss of the filter.
  • Step 120 filling the recess with a sacrificial material, wherein the upper surface of the sacrificial material is flush with the upper surface of the substrate.
  • the sacrificial material is filled, wherein the sacrificial material may be metal aluminum, metallic magnesium, silicon dioxide or tantalum material or the like.
  • the planarization treatment is performed by a chemical mechanical polishing process (CMP) so that the upper surface of the sacrificial material is flush with the upper surface of the substrate, facilitating the subsequent preparation of the piezoelectric layer.
  • CMP chemical mechanical polishing process
  • Step 130 covering the first piezoelectric layer on the upper surface of the substrate and the upper surface of the sacrificial material.
  • Covering the first piezoelectric layer on the upper surface of the substrate and the upper surface of the sacrificial material includes forming the first piezoelectric layer by an epitaxial growth process, a thin film transfer process, or a wafer thinning process.
  • a first piezoelectric layer of single crystal aluminum nitride may be obtained by epitaxial growth of a planarized substrate surface by a metal organic chemical vapor deposition (MOCVD) method; or a single crystal nitride may be prepared on other substrates.
  • MOCVD metal organic chemical vapor deposition
  • the aluminum is separated, and the first piezoelectric layer of the prepared single crystal aluminum nitride is transferred and bonded onto the support layer by a film transfer process; or the wafer may be formed by using a liquid crystal polymer (LCP) adhesive.
  • LCP liquid crystal polymer
  • Step 140 forming a first electrode and a temperature compensation layer on a side of the first piezoelectric layer away from the substrate, wherein a projection of the first electrode on the substrate is located in a region where the groove is located in a direction perpendicular to the substrate .
  • a first electrode 5 is sputter deposited on the exposed side of the first piezoelectric layer 4 away from the substrate 1, wherein the first electrode 5 may be an interdigital electrode or a planar electrode,
  • the temperature compensation layer 3 covers the first electrode 5, and the temperature compensation layer 3 may be a SiO 2 material, and the interdigital electrodes are distributed in the same layer as the temperature compensation layer 3.
  • the temperature compensation layer 3 can serve as a low sound velocity layer, so that the acoustic energy is mainly concentrated in the piezoelectric material layer, so that the acoustic energy can be confined between the first piezoelectric layer 4 and the interdigital electrodes, which can reduce the loss and increase the piezoelectricity.
  • the Q value of the resonator is sputter deposited on the exposed side of the first piezoelectric layer 4 away from the substrate 1, wherein the first electrode 5 may be an interdigital electrode or a planar electrode,
  • the temperature compensation layer 3 covers the first electrode 5, and the temperature compensation layer 3 may
  • the projection of the first electrode 5 on the substrate 1 is located in the region where the groove is located. Therefore, there are various situations in the position distribution of the first electrode 5 above the substrate 1.
  • the embodiment of the piezoelectric resonator described above is omitted here.
  • Step 150 removing the sacrificial material to form a cavity.
  • a hole is opened in a region where the groove is located, and the opening is opened.
  • the holes etch away the sacrificial material.
  • a sacrificial material may be etched away by opening a hole in one side surface of the substrate 1 (e.g., opening the lower surface of the provided substrate 1).
  • the cavity may contain air, nitrogen, or the like or the cavity may remain in a vacuum state.
  • a second electrode 6 may be disposed in the cavity, wherein the second electrode 6 may be an interdigitated electrode or a planar electrode.
  • the second electrode 6 is deposited on one side surface of the first piezoelectric layer 4 so that it can exist in the cavity.
  • the second electrode 6 is deposited on the upper surface of the sacrificial material, and the first piezoelectric layer 4 is deposited on the side of the second electrode 6 away from the sacrificial material.
  • the transverse bulk wave can be excited in the piezoelectric layer to be applied to the narrow bandwidth filter; when the second electrode 6 is a planar electrode, the longitudinal bulk wave can be excited It is applied to a filter with a relatively wide bandwidth.
  • the technical solution provided by the embodiment of the present application can form a cavity on the upper surface of the substrate to form a cavity between the groove and the first piezoelectric layer, thereby effectively preventing sound energy from leaking into the substrate and reducing sound energy.
  • the loss in the substrate can obtain a piezoelectric resonator with a high Q value; and the temperature compensation layer is provided, so that the piezoelectric resonator maintains a lower frequency temperature coefficient and effectively improves the temperature compensation efficiency.
  • the application range of the piezoelectric resonator can be expanded by interacting with the first electrode through the second electrode, and can be applied to a filter having a narrow bandwidth and a wide bandwidth, and the piezoelectric device of the embodiment
  • the resonator is small in size.
  • the piezoelectric resonator and the piezoelectric resonator preparation method provided by the embodiments of the present invention effectively prevent the sound wave energy from leaking into the substrate, reduce the loss of the acoustic wave energy in the substrate, and obtain the piezoelectric resonator with high Q value. And can effectively improve the temperature compensation efficiency.

Landscapes

  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Surface Acoustic Wave Elements And Circuit Networks Thereof (AREA)
  • Piezo-Electric Or Mechanical Vibrators, Or Delay Or Filter Circuits (AREA)

Abstract

一种压电谐振器和压电谐振器的制备方法。其中，压电谐振器包括：衬底，所述衬底的上表面形成有一凹槽；第一压电层，覆盖于所述衬底的上表面以及所述凹槽的开口，以使所述凹槽与所述第一压电层形成空腔；第一电极和温度补偿层，均设置在所述第一压电层远离所述衬底的一侧，在垂直于所述衬底的方向上，所述第一电极在所述衬底上的投影位于所述凹槽所在的区域。

Description

压电谐振器和压电谐振器的制备方法 技术领域
本申请实施例涉及声波谐振器技术领域，例如涉及一种压电谐振器和压电谐振器的制备方法。
背景技术
表面声波器件(如：声表面波滤波器(Surface Acoustic Wave，SAW))是将电信号转换为表面波并进行信号处理的电路元件，可以作为滤波器、谐振器等被广泛使用。其中品质因数(Q)和频率温度系数(Temperature Coefficient of Frequency，TCF)使表面声波器件在压电谐振器等电子元件的研究和发展中有重要意义。
图1是相关技术中的一种压电谐振器的剖面结构示意图，如图1所示，压电谐振器(如SAW谐振器)包括衬底1，位于衬底1上表面的高声速层2(氮化铝材料)，位于高声速层2远离衬底1一侧表面的低声速层3(二氧化硅材料)，位于低声速层3远离高声速层2一侧表面的压电层4(钽酸锂材料)，以及位于压电层4远离低声速层3一侧表面的电极5。由于低声速层3和高声速层2之间存在声失配，使得在低声速层3和高声速层2的界面的声波发生反射，因此可以减少声波能量的泄漏。但是此种结构容易使纵向声波通过高声速层2泄漏进入衬底1，增加声波能量在衬底1中的损耗，导致压电谐振器的Q值下降。
发明内容
本申请实施例提供的一种压电谐振器和压电谐振器的制备方法，有效避免了声波能量泄漏到衬底中，降低了声波能量在衬底中的损耗，可得到高Q值的压电谐振器，并且使得到的压电谐振器具有较低的频率温度系数。
本申请实施例提供了一种压电谐振器，包括：
衬底，所述衬底的上表面形成有一凹槽；
第一压电层，覆盖于所述衬底的上表面以及所述凹槽的开口，以使所述凹槽与所述第一压电层形成空腔；
第一电极和温度补偿层，均设置在所述第一压电层远离所述衬底的一侧， 在垂直于所述衬底的方向上，所述第一电极在所述衬底上的投影位于所述凹槽所在的区域。
本申请实施例还提供了一种压电谐振器的制备方法，包括：
在衬底的上表面形成凹槽；
在所述凹槽中填充牺牲材料，其中，所述牺牲材料的上表面与所述衬底的上表面齐平；
在所述衬底的上表面以及所述牺牲材料的上表面覆盖第一压电层；
在所述第一压电层远离所述衬底的一侧形成第一电极和温度补偿层，其中，在垂直于所述衬底的方向上，所述第一电极位于所述凹槽所在的区域；
去除所述牺牲材料形成空腔。
本申请实施例提供的技术方案，通过在衬底的上表面形成有一凹槽，使凹槽与第一压电层形成空腔，使得声波经空腔层形成全反射，可以有效避免了声波能量泄漏到衬底中，降低了声波能量在衬底中的损耗，可得到高Q值的压电谐振器；并且设置的温度补偿层可以使得压电谐振器保持较低的频率温度系数，可以有效改善温度补偿效率。空腔中存在的第二电极，通过与第一电极相互作用可以扩大压电谐振器的应用范围，同时在密封空腔上制备的压电谐振器体积可以更小。
附图说明
图1是相关技术中的一种压电谐振器的剖面结构示意图。
图2是一实施例提供的一种压电谐振器的剖面结构示意图。
图3是一实施例提供的另一种压电谐振器的剖面结构示意图。
图4是一实施例提供的另一种压电谐振器的剖面结构示意图。
图5是一实施例提供的另一种压电谐振器的剖面结构示意图。
图6是一实施例提供的另一种压电谐振器的剖面结构示意图。
图7是一实施例提供的另一种压电谐振器的剖面结构示意图。
图8是一实施例提供的另一种压电谐振器的剖面结构示意图。
图9是一实施例提供的另一种压电谐振器的剖面结构示意图。
图10是一实施例提供的一种压电谐振器的制备方法的流程示意图。
具体实施方式
下面结合附图和实施例对本申请作进一步的说明。可以理解的是，此处所描述的具体实施例仅用于解释本申请，而非对本发明的限定。另外还需要说明的是，为了便于描述，附图中仅示出了与本申请相关的部分而非全部结构。
本申请实施例提供一种压电谐振器，该装置适用于通信技术领域。图2是本申请一实施例提供的压电谐振器的剖面结构示意图。参见图2，该谐振器的结构包括依次设置的衬底1，第一压电层4，第一电极5和温度补偿层3，其中，衬底1的上表面形成有一凹槽11；第一压电层4，覆盖于衬底1的上表面以及凹槽11的开口，以使凹槽11与第一压电层4形成空腔；其中，凹槽11的剖面结构可以为矩形或弧形，但是其形状不限于矩形或弧形，只要可以最大可能地避免声波能量泄露到衬底中即可。第一电极5和温度补偿层3，均设置在第一压电层4远离衬底1的一侧，在垂直于衬底1的方向上，第一电极5在衬底1上的投影位于凹槽11所在的区域，其中，设置在第一压电层4远离衬底1一侧的第一电极5可以在温度补偿层3的上表面，或者设置在第一压电层4远离衬底1一侧的第一电极5可以与温度补偿层3进行同层设置。
本申请实施例提供的技术方案，通过在衬底的上表面形成有一凹槽，使凹槽与第一压电层形成空腔，可以有效避免了声波能量泄漏到衬底中，降低了声波能量在衬底中的损耗，可得到高Q值的压电谐振器；并且设置的温度补偿层，可以使得压电谐振器保持较低的频率温度系数，可以有效改善温度补偿效率。
在一实施例中，第一电极位于第一压电层远离衬底一侧的表面，温度补偿层覆盖第一电极。
如图2所示，压电谐振器包括衬底1，第一电极5，第一压电层4和温度补偿层3。其中衬底1材料可以为硅，可做高声速支撑基板，其电阻率约为1000Ω·cm或以上，当该压电谐振器作为滤波器使用时，可以减小滤波器的插入损耗。第一压电层4覆盖在开设有凹槽11的衬底1得到空腔结构，第一电极5位于第一压电层4远离衬底1一侧的上表面，并使温度补偿层3覆盖第一电极5。第一电极5可以为叉指电极，在第一压电层4的上表面均匀分布，此时叉指电极中相邻两电极之间填充温度补偿层3的材料。其中叉指电极可以激发多种 模式的不同声波。
第一压电层4可以为氮化铝(AIN)、氧化锌(ZnO)、铌酸锂(LiNbO 3)或钽酸锂(LiTaO 3)等，第一压电层4一般为负温度系数材料，即随着温度的升高声速会变小，因为材料的跨原子力减小会导致材料弹性常数的减小，从而减小声速。温度补偿层的材料可以为正温度系数材料，例如可以为二氧化硅SiO 2，SiO 2作为一种独特的材料，其硅-氧链随着温度升高而拉伸，因此其刚度具有正温度系数，在SiO 2内传播的声波，其声速呈现出正的温度系数。所以，SiO 2被用来补偿压电谐振器因温度改变导致的频率偏移，可以对第一压电层4实现较好的温度补偿。此外，SiO 2可以为低声速层，其厚度可以为纳米级，对制备谐振器的Q和机电耦合系数(k t 2)的影响较小。
在一实施例中，温度补偿层位于第一压电层远离衬底一侧的表面，第一电极位于温度补偿层远离衬底的一侧。在一实施例中，第一电极位于温度补偿层远离衬底一侧的表面。在一实施例中，压电谐振器还可以包括位于温度补偿层和第一电极之间的第二压电层，第一电极位于第二压电层远离衬底一侧的表面。
如图3所示，压电谐振器包括衬底1，第一电极5，第一压电层4和温度补偿层3，第一电极5位于温度补偿层3远离衬底1的一侧，其中，第一电极5位于温度补偿层3远离衬底1一侧的上表面。
第一电极5可以为叉指电极，在温度补偿层3的上表面均匀分布，第一电极5与温度补偿层3进行隔层设置。叉指电极的材料可以为铝Al或者铝铜AlCu等金属合金，其作用是可将电信号通过叉指状换能器转换成声信号。此外，叉指电极的电极膜厚度约为50nm-200nm，可以保证电极的电阻率较小。叉指电极通过在温度补偿层3和第一压电层4中形成电场，从而激发或获取滤波器和谐振器特定振动模式中的声波。
或者，如图4所示，压电谐振器包括衬底1，第一电极5，第一压电层4、温度补偿层3及位于温度补偿层3和第一电极5之间的第二压电层7，第一电极5位于第二压电层7远离衬底1一侧的表面。由于第一压电层4和第二压电层7一般为负温度系数材料，而温度补偿层3可以为SiO 2，通过力学计算，发现在特定的振动模式下，当温度补偿层3位于压电谐振器结构中间位置时，温度补 偿效率可以达到较高值。由于压电谐振器的频率温度系数(TCF)由每层结构的厚度和它们在谐振腔内的相对位置和作用所决定。一般情况下，为了获得较低的TCF，需要在压电谐振器的上方或下方沉积一层较厚的SiO 2来补偿压电谐振器的谐振频率随温度改变的漂移量。本实施例的压电谐振器，可以通过制备较薄的温度补偿层(SiO 2)，实现温度补偿，大大提高了温度补偿的效率。
在一实施例中，压电谐振器还可以包括第二电极，第二电极位于空腔中，且设置于第一压电层靠近衬底一侧的表面。
示例性地，可继续参见图3，压电谐振器还包括第二电极6，第二电极6位于空腔中，且设置于第一压电层4靠近衬底1一侧的表面。其中第一电极5可以为叉指电极，第二电极6可以为面状电极；通过叉指电极与面状电极的相互作用，使得在第一压电层4和温度补偿层3中激发横向体波，因为温度补偿层3为非压电材料SiO 2在第一电极5和第二电极6之间，温度补偿层3消耗了部分第一压电层4(如AIN)的电压，使得第一压电层4上的电场强度降低，进而导致机电耦合系数k t 2下降，而较低的有效机电耦合系数适用于窄带滤波器。
在一实施例中，压电谐振器还包括下述至少之一：第一电极为叉指电极或面状电极，和第二电极为叉指电极或面状电极。第一电极和第二电极中至少一个电极的形状及设置位置可以有多种变化，并不仅限于上述几种情况，通过设置第一电极和第二电极中至少一个电极的形状及位置可以得到不同模式的波，扩大了压电谐振器的应用范围。
如图5所示，第二电极6为叉指电极，且设置于第一压电层4靠近衬底1一侧的表面。在该方式中，第一电极5可以为叉指电极，位于温度补偿层3远离衬底1一侧的上表面。
在一实施例中，如图6所示，第二电极6为叉指电极，且设置于第一压电层4靠近衬底1一侧的表面。在该方式中，第一电极5可以为叉指电极，位于第一压电层4远离衬底1一侧的表面，温度补偿层3覆盖第一电极5。
叉指电极可以将电信号转化成声信号，第一电极5与第二电极6均为叉指电极，第一电极5与第二电极6相互配合，依据不同的电路连接方式，可以激发压电谐振器产生横向体波、纵向体波或者其他形式的声波，横向体波一般适 用于窄带滤波器。
在一实施例中，如图7所示，第二电极6为面状电极，且设置于第一压电层4靠近衬底1一侧的表面。在该方式中，第一电极5可以为叉指电极，位于第一压电层4远离衬底1一侧的表面，温度补偿层3覆盖第一电极5。叉指电极可以将电信号转变成声信号，通过与面状电极配合可以激发横向体波。在一实施例中，如图4所示，第二电极6为面状电极，且设置于第一压电层4靠近衬底1一侧的表面。第一电极5为面状电极，设置在第二压电层7远离衬底1的上表面，第一压电层4与第二压电层7之间设置有温度补偿层3。
在一实施例中，如图8所示，第二电极6为面状电极，且设置于第一压电层4靠近衬底1一侧的表面。在该方式中，第一电极5可以为面状电极，位于第一压电层4远离衬底1一侧的表面，温度补偿层3覆盖第一电极5。两个面状电极可以激发纵向体波，可以应用在移动通信系统中。
在一实施例中，如图9所示，第二电极6为面状电极，且设置于第一压电层4靠近衬底1一侧的表面。在该方式中，第一电极5可以为面状电极，位于温度补偿层3远离衬底1一侧的上表面。
参见图4、图8或图9，第一电极5为面状电极，第二电极6位于空腔中的位置，其中第二电极6可以为面状电极；第一电极5、第二电极6均为面妆电极，与第一压电层4组成的结构类似于(薄膜腔声谐振滤波器film bulk acoustic resonator，FBAR)结构，相对容易控制寄生振动模式(spurious mode)的产生，降低其对压电谐振器的Q和k t 2的影响，通过设置一对面状电极，可以在压电材料中激发纵向体波，可以应用于宽带滤波器。
上述压电谐振器结构中，温度补偿层(SiO 2)一般沉积在压电谐振器的最上方，它具有双层作用，其一，可以起到温度补偿的作用；其二，这层SiO 2可以作为保护层，防止压电谐振器受到外界水汽、颗粒等物质的污染。为了能有良好的滤波特性(带宽)，SiO 2层的标准厚度应是第一压电层厚度的一半以下。若希望有较好的谐波特性和良好的温度补偿特性，SiO 2层的厚度也可以为增加到第一压电层厚度的1.5倍。
本申请实施例中提供的压电谐振器结构，将温度补偿层(SiO 2)放在第一压 电层的上方，使得声波能量主要集中的第一压电层中，并在第一压电层与空腔的界面处形成全反射，避免能量泄露到衬底中，此种结构可以保持压电谐振器有较高的Q值和较低的频率温度系数(TCF)，尤其是应用于下述情况，在滤波器非常陡峭的滚降区域，由于温度变化而引起细微的频率漂移都有可能导致滤波器在滚降区域不满足技术指标。此外，还可以应用在解决不同通讯标准互相干扰的系统中，例如集成卫星收音机或者GPS导航的移动手机系统。
另外，本申请实施例还提供了一种压电谐振器的制备方法，图10为本申请实施例提供的一种压电谐振器的制备方法的流程示意图，包括：
步骤110、在衬底的上表面形成凹槽。
衬底作为支撑层，支撑层可以为硅衬底，在硅衬底上可以通过深反应离子刻蚀工艺(DRIE)在该支撑层上通过掩膜或光刻除去部分硅材料，凹槽的剖面结构可以为矩形或弧形，其凹槽的剖面结构深度可以为纳米级或微米级，凹槽的尺寸可以根据实际需要进行相应的选择。其中硅衬底可以为高声速材料层，其电阻率可以为1000Ω·cm或以上，这样可以减小滤波器的插入损耗。
步骤120、在凹槽中填充牺牲材料，其中，牺牲材料的上表面与衬底的上表面齐平。
在得到的凹槽结构中，通过填充牺牲材料，其中牺牲材料可以为金属铝，金属镁，二氧化硅或锗材料等。通过化学机械抛光工艺(CMP)，进行平坦化处理使得牺牲材料的上表面与衬底的上表面齐平，便于后续中进行压电层的制备。
步骤130、在衬底的上表面以及牺牲材料的上表面覆盖第一压电层。
在衬底的上表面以及牺牲材料的上表面覆盖第一压电层，包括：通过外延生长工艺、薄膜转移工艺或晶圆减薄工艺形成第一压电层。例如，在平坦化处理的衬底表面通过金属有机化合物化学气相沉积(MOCVD)方法外延生长可以获得单晶氮化铝的第一压电层；或者可以将制备在其他衬底上单晶氮化铝进行分离，通过薄膜转移的工艺技术将制备的单晶氮化铝的第一压电层转移压合到支撑层上；或者还可以通过使用液晶聚合物(LCP)粘合剂将晶圆片(比如氮化铝)与支撑层表面粘结，倒装粘结在支撑衬底上，通过将晶圆片进行研磨、减薄及抛光处理以保证其平整度，并得到实际需要的薄膜厚度。
步骤140、在第一压电层远离衬底的一侧形成第一电极和温度补偿层，其中，在垂直于衬底的方向上，第一电极在衬底上的投影位于凹槽所在的区域。
继续参见图7-图8，在露出的第一压电层4远离衬底1的一侧溅射沉积一层第一电极5，其中第一电极5可以为叉指电极或面状电极，将温度补偿层3覆盖第一电极5，温度补偿层3可以为SiO 2材料，将叉指电极与温度补偿层3同层分布。温度补偿层3可以作为低声速层，使得声波能量主要集中在压电材料层中，这样可以将声波能量限制在第一压电层4和叉指电极之间，可以减少损耗并提高压电谐振器的Q值。
此外，在垂直于衬底1的方向上，第一电极5在衬底1上的投影位于凹槽所在的区域。所以第一电极5在衬底1上方的位置分布存在多种情况，可参考上述压电谐振器的实施例，此处不再赘述。
步骤150、去除牺牲材料形成空腔。
继续参见图2-图9，在第一压电层4的上方制备第一电极5和温度补偿层3后，沿垂直于衬底1的方向上，在凹槽所在的区域开孔，通过开的孔刻蚀掉牺牲材料。示例性地，可以在衬底1的一侧表面开孔(如：在提供的衬底1下表面进行开孔)，蚀刻掉牺牲材料。以暴露出第一压电层4与支撑衬底之间的空腔，其中空腔内可以包含空气、氮气等或者空腔可以保持真空状态。在空腔中可以设置有第二电极6，其中第二电极6可以为叉指电极或面状电极。薄膜转移或是晶圆片压合在支撑衬底之前，将第二电极6沉积到第一压电层4的一侧表面，使其可以存在空腔中。或者在牺牲材料的上表面沉积第二电极6，再在第二电极6远离牺牲材料的一侧沉积第一压电层4。其中当第二电极6为叉指电极时，可以在压电层中激发横向体波，使其应用于窄的带宽滤波器中；当第二电极6为面状电极时，可以激发纵向体波，使其应用于带宽相对较宽的滤波器中。
本申请实施例提供的技术方案，通过在衬底的上表面形成有一凹槽，使凹槽与第一压电层形成空腔，可以有效避免了声波能量泄漏到衬底中，降低了声波能量在衬底中的损耗，可得到高Q值的压电谐振器；并且设置温度补偿层，可以使得压电谐振器保持较低的频率温度系数，有效改善温度补偿效率。空腔 中存在第二电极时，通过第二电极与第一电极相互作用可以扩大压电谐振器的应用范围，可以应用于带宽较窄和带宽较宽的滤波器中，本实施例的压电谐振器的体积较小。
工业实用性
本申请实施例提供的压电谐振器和压电谐振器制备方法，有效避免了声波能量泄漏到衬底中，降低了声波能量在衬底中的损耗，可得到高Q值的压电谐振器，并且可以有效改善温度补偿效率。

Claims (13)

  1. 一种压电谐振器，包括：
    衬底，所述衬底的上表面形成有一凹槽；
    第一压电层，覆盖于所述衬底的上表面以及所述凹槽的开口，以使所述凹槽与所述第一压电层形成空腔；
    第一电极和温度补偿层，均设置在所述第一压电层远离所述衬底的一侧，在垂直于所述衬底的方向上，所述第一电极在所述衬底上的投影位于所述凹槽所在的区域。
  2. 根据权利要求1所述的压电谐振器，其中，所述第一电极位于所述第一压电层远离所述衬底一侧的表面，所述温度补偿层覆盖所述第一电极。
  3. 根据权利要求1所述的压电谐振器，其中，所述温度补偿层位于所述第一压电层远离所述衬底一侧的表面，所述第一电极位于所述温度补偿层远离所述衬底的一侧。
  4. 根据权利要求3所述的压电谐振器，其中，所述第一电极位于所述温度补偿层远离所述衬底一侧的表面。
  5. 根据权利要求3所述的压电谐振器，其中，还包括位于所述温度补偿层和所述第一电极之间的第二压电层，所述第一电极位于所述第二压电层远离所述衬底一侧的表面。
  6. 根据权利要求1-5任一项所述的压电谐振器，其中，还包括第二电极，所述第二电极位于所述空腔中，且设置于所述第一压电层靠近所述衬底一侧的表面。
  7. 根据权利要求6所述的压电谐振器，还包括下述至少之一：所述第一电极为叉指电极或面状电极，和所述第二电极为叉指电极或面状电极。
  8. 根据权利要求1所述的压电谐振器，其中，所述衬底的材料为硅。
  9. 根据权利要求1所述的压电谐振器，其中，所述温度补偿层的材料为正温度系数材料。
  10. 根据权利要求9所述的压电谐振器，其中，所述温度补偿层的材料为二氧化硅。
  11. 根据权利要求1所述的压电谐振器，其中，所述第一电极的厚度为100nm-200nm。
  12. 一种压电谐振器的制备方法，包括：
    在衬底的上表面形成凹槽；
    在所述凹槽中填充牺牲材料，其中，所述牺牲材料的上表面与所述衬底的上表面齐平；
    在所述衬底的上表面以及所述牺牲材料的上表面覆盖第一压电层；
    在所述第一压电层远离所述衬底的一侧形成第一电极和温度补偿层，其中，在垂直于所述衬底的方向上，所述第一电极在所述衬底上的投影位于所述凹槽所在的区域；
    去除所述牺牲材料形成空腔。
  13. 根据权利要求12所述的压电谐振器的制备方法，其中，去除所述牺牲材料形成空腔，包括：
    沿垂直于所述衬底的方向上，在所述凹槽所在的区域开孔，通过所开的孔刻蚀掉所述牺牲材料。
PCT/CN2018/085289 2017-11-14 2018-05-02 压电谐振器和压电谐振器的制备方法 WO2019095640A1 (zh)

Priority Applications (3)

Application Number Priority Date Filing Date Title
JP2020526508A JP2021503229A (ja) 2017-11-14 2018-05-02 圧電共振器および圧電共振器の製造方法
US16/754,169 US20210211115A1 (en) 2017-11-14 2018-05-02 Piezoelectric resonator and manufacturing method of piezoelectric resonator
KR1020207010371A KR20200052928A (ko) 2017-11-14 2018-05-02 압전 공진기 및 압전 공진기의 제조방법

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
CN201711121168.8 2017-11-14
CN201721512611.X 2017-11-14
CN201721512611.XU CN207339804U (zh) 2017-11-14 2017-11-14 一种压电谐振器
CN201711121168.8A CN107733395A (zh) 2017-11-14 2017-11-14 一种压电谐振器和压电谐振器的制备方法

Publications (1)

Publication Number Publication Date
WO2019095640A1 true WO2019095640A1 (zh) 2019-05-23

Family

ID=66539318

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2018/085289 WO2019095640A1 (zh) 2017-11-14 2018-05-02 压电谐振器和压电谐振器的制备方法

Country Status (4)

Country Link
US (1) US20210211115A1 (zh)
JP (1) JP2021503229A (zh)
KR (1) KR20200052928A (zh)
WO (1) WO2019095640A1 (zh)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112653417A (zh) * 2020-12-18 2021-04-13 广东广纳芯科技有限公司 声表面波谐振器及该声表面波谐振器的制造方法
CN113437947A (zh) * 2021-07-06 2021-09-24 电子科技大学 一种基于声子晶体抑制侧边能量辐射的薄膜体声波谐振器
EP4027514A4 (en) * 2019-09-05 2023-10-25 Changzhou Chemsemi Co., Ltd. DEVICE FOR ACOUSTIC VOLUME WAVE RESONANCE AND ACOUSTIC VOLUME WAVE FILTER

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB201802659D0 (en) * 2018-02-19 2018-04-04 Cambridge Entpr Ltd Resonator and method for operation of resonator
JP7168009B2 (ja) * 2019-01-31 2022-11-09 株式会社村田製作所 弾性波デバイスおよびマルチプレクサ
CN114978089B (zh) * 2022-05-20 2023-11-21 武汉敏声新技术有限公司 一种谐振器及其制备方法、滤波器

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1326332A2 (en) * 2002-01-08 2003-07-09 Murata Manufacturing Co., Ltd. Piezoelectric resonator, piezoelectric filter, duplexer, communication apparatus, and method for manufacturing piezoelectric resonator
CN1507152A (zh) * 2002-12-11 2004-06-23 Tdk��ʽ���� 压电谐振滤波器和双工器
JP2005311849A (ja) * 2004-04-23 2005-11-04 Seiko Epson Corp 圧電薄膜共振子、フィルタ及び圧電薄膜共振子の製造方法
CN103873010A (zh) * 2014-03-17 2014-06-18 电子科技大学 一种压电薄膜体声波谐振器及其制备方法
CN106209002A (zh) * 2016-06-29 2016-12-07 电子科技大学 一种新型薄膜体声波谐振器及其制备方法
CN107733395A (zh) * 2017-11-14 2018-02-23 安徽云塔电子科技有限公司 一种压电谐振器和压电谐振器的制备方法

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004147246A (ja) * 2002-10-28 2004-05-20 Matsushita Electric Ind Co Ltd 圧電振動子、それを用いたフィルタ及び圧電振動子の調整方法
JP4743258B2 (ja) * 2008-10-31 2011-08-10 株式会社村田製作所 圧電デバイスの製造方法
JP5433367B2 (ja) * 2008-11-19 2014-03-05 日本碍子株式会社 ラム波装置
JP2011166259A (ja) * 2010-02-05 2011-08-25 Murata Mfg Co Ltd 弾性表面波装置
US8253513B2 (en) * 2010-03-16 2012-08-28 Hao Zhang Temperature compensated thin film acoustic wave resonator
JP2013214954A (ja) * 2012-03-07 2013-10-17 Taiyo Yuden Co Ltd 共振子、周波数フィルタ、デュプレクサ、電子機器及び共振子の製造方法
JP5904591B2 (ja) * 2012-03-15 2016-04-13 太陽誘電株式会社 弾性波デバイス
US9401691B2 (en) * 2014-04-30 2016-07-26 Avago Technologies General Ip (Singapore) Pte. Ltd. Acoustic resonator device with air-ring and temperature compensating layer

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1326332A2 (en) * 2002-01-08 2003-07-09 Murata Manufacturing Co., Ltd. Piezoelectric resonator, piezoelectric filter, duplexer, communication apparatus, and method for manufacturing piezoelectric resonator
CN1507152A (zh) * 2002-12-11 2004-06-23 Tdk��ʽ���� 压电谐振滤波器和双工器
JP2005311849A (ja) * 2004-04-23 2005-11-04 Seiko Epson Corp 圧電薄膜共振子、フィルタ及び圧電薄膜共振子の製造方法
CN103873010A (zh) * 2014-03-17 2014-06-18 电子科技大学 一种压电薄膜体声波谐振器及其制备方法
CN106209002A (zh) * 2016-06-29 2016-12-07 电子科技大学 一种新型薄膜体声波谐振器及其制备方法
CN107733395A (zh) * 2017-11-14 2018-02-23 安徽云塔电子科技有限公司 一种压电谐振器和压电谐振器的制备方法

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP4027514A4 (en) * 2019-09-05 2023-10-25 Changzhou Chemsemi Co., Ltd. DEVICE FOR ACOUSTIC VOLUME WAVE RESONANCE AND ACOUSTIC VOLUME WAVE FILTER
CN112653417A (zh) * 2020-12-18 2021-04-13 广东广纳芯科技有限公司 声表面波谐振器及该声表面波谐振器的制造方法
CN113437947A (zh) * 2021-07-06 2021-09-24 电子科技大学 一种基于声子晶体抑制侧边能量辐射的薄膜体声波谐振器

Also Published As

Publication number Publication date
KR20200052928A (ko) 2020-05-15
JP2021503229A (ja) 2021-02-04
US20210211115A1 (en) 2021-07-08

Similar Documents

Publication Publication Date Title
WO2019095640A1 (zh) 压电谐振器和压电谐振器的制备方法
KR102367379B1 (ko) 표면 음향파 디바이스를 위한 하이브리드 구조체
CN111245397B (zh) 体声波谐振器及制造方法、体声波谐振器单元、滤波器及电子设备
KR102428548B1 (ko) 접합 방법
CN107733395A (zh) 一种压电谐振器和压电谐振器的制备方法
CN109075758B (zh) 接合体和弹性波元件
JP7130841B2 (ja) 薄膜バルク音響波共振器及びその製造方法
US9876158B2 (en) Component comprising stacked functional structures and method for producing same
JP7081041B2 (ja) 薄膜バルク音響波共振器とその製造方法、フィルタ、および無線周波数通信システム
CN207339804U (zh) 一种压电谐振器
WO2021109444A1 (zh) 体声波谐振器及其制造方法、滤波器及电子设备
JP2011120241A (ja) Ｆｂａｒタイプのバルク波の音響共振器を製作する方法
EP4050795A1 (en) Bulk acoustic resonator, filter, and electronic device
US20240088869A1 (en) Frequency-tunable film bulk acoustic resonator and preparation method therefor
CN111555733A (zh) 一种兰姆波谐振器结构及其制备方法
US8186030B2 (en) Method for manufacturing elastic wave device
CN115395918B (zh) 声波谐振器及其设计方法、制造方法
WO2004088840A1 (ja) 圧電薄膜デバイス及びその製造方法
WO2021189964A1 (zh) 一种薄膜体声波谐振器及其制造方法
JP2002372974A (ja) 薄膜音響共振器及びその製造方法
JP2008236556A (ja) 薄膜バルク波共振器
WO2021042345A1 (zh) 一种体声波谐振装置的形成方法
CN115412042A (zh) 薄膜体声波谐振器及其制备方法
JP2005033379A (ja) 薄膜バルク波振動子およびその製造方法
CN109995342A (zh) 空气隙型薄膜体声波谐振器的制备方法

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 18877407

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 20207010371

Country of ref document: KR

Kind code of ref document: A

ENP Entry into the national phase

Ref document number: 2020526508

Country of ref document: JP

Kind code of ref document: A

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 18877407

Country of ref document: EP

Kind code of ref document: A1