WO2023142483A1 - 叉指换能结构、谐振器、谐振器制作方法及滤波器 - Google Patents

叉指换能结构、谐振器、谐振器制作方法及滤波器 Download PDF

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WO2023142483A1
WO2023142483A1 PCT/CN2022/116769 CN2022116769W WO2023142483A1 WO 2023142483 A1 WO2023142483 A1 WO 2023142483A1 CN 2022116769 W CN2022116769 W CN 2022116769W WO 2023142483 A1 WO2023142483 A1 WO 2023142483A1
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Prior art keywords
electrode
electrodes
interdigital
bus bar
layer
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PCT/CN2022/116769
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English (en)
French (fr)
Inventor
宋崇希
王放
姚艳龙
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江苏卓胜微电子股份有限公司
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Publication of WO2023142483A1 publication Critical patent/WO2023142483A1/zh

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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
    • H03H9/02—Details
    • H03H9/02535—Details of surface acoustic wave devices
    • H03H9/02637—Details concerning reflective or coupling arrays
    • H03H9/02685—Grating lines having particular arrangements
    • H03H9/02724—Comb like grating lines
    • H03H9/02732—Bilateral comb like grating lines
    • 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
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
    • H03H9/46—Filters
    • H03H9/64—Filters using surface acoustic waves

Definitions

  • the present disclosure relates to the technical field of resonators, and in particular to an interdigital transducer structure, a resonator, a manufacturing method of the resonator, and a filter.
  • the radio frequency filter currently widely used in wireless communication terminals is the SAW filter, which is responsible for filtering the radio frequency signals of the receiving and transmitting channels, and outputs signals of specific frequencies among the various input radio frequency signals.
  • SAW filter which is responsible for filtering the radio frequency signals of the receiving and transmitting channels, and outputs signals of specific frequencies among the various input radio frequency signals.
  • the radio frequency filter composed of the resonator can achieve low insertion loss, smooth passband, and high Q value (the Q value of the inductance device is in a certain At one frequency, the ratio of inductive reactance to equivalent loss resistance) and excellent low frequency temperature characteristics.
  • High-performance surface acoustic wave resonator is a relatively new type of resonator. Since its piezoelectric material is bonded by composite multi-layer materials, the propagation and working mode of sound waves are different from conventional surface acoustic wave resonators. If the conventional surface acoustic wave resonator is still used The design method of the surface acoustic wave resonator and the RF filter will have strong transverse mode ripples and serious passband clutter, which will lead to the deterioration of the overall device performance.
  • an IDT structure a resonator, a manufacturing method of the resonator, and a filter are provided.
  • an interdigital transduction structure includes: a first bus bar and a second bus bar arranged in parallel, and multiple bus bars are arranged on the first bus bar.
  • a first electrode and a plurality of second electrodes are arranged on the second bus bar, and the plurality of first electrodes and the plurality of second electrodes are arranged at intervals between the first bus bar and the second bus bar the middle area between
  • the middle region includes an interdigital area and a monopolar area not belonging to the interdigital area, and the interdigital area is the end edge of the plurality of first electrodes away from the first bus bar and the plurality of the second electrode is away from the area formed between the end edges of the second bus bar;
  • the first electrodes and the second electrodes in the unipolar region are connected by a plurality of metal strips;
  • a metal thickening layer is provided at the electrode end of each first electrode and at the corresponding position in the lateral direction of the second electrode adjacent to the first electrode;
  • a metal thickening layer is provided at the electrode end of each second electrode and at the corresponding position in the lateral direction of the first electrode adjacent to the second electrode.
  • the unipolar region includes a first unipolar region and a second unipolar region, in the first unipolar region adjacent first electrodes are connected by a plurality of metal strips, and in the first unipolar region The adjacent second electrodes in the second unipolar region are connected by a plurality of metal strips.
  • the number of metal strips disposed between adjacent first electrodes and/or between adjacent second electrodes is the same.
  • the metal strips are rectangular metal strips arranged in parallel, or rectangular metal strips arranged obliquely at a preset angle.
  • the metal strips on both sides of the first electrode and/or the second electrode are aligned with the corresponding first electrode and/or second electrode. The same position on the two electrodes is connected.
  • the lower bases of the metal strips connected to both sides of the first electrode or the second electrode point to the same or opposite directions to the upper base.
  • the metal strips on both sides of the first electrode and/or the second electrode are alternately arranged at the corresponding two sides of the first electrode and/or the second electrode at the same distance.
  • the first electrodes or the second electrodes are connected through a plurality of metal strips; wherein each metal strip penetrates each first electrode or each second electrode.
  • the metal thickening layer is disposed on the upper surface or the lower surface of the first electrode and the second electrode.
  • the dummy finger strip is connected to the first bus bar or the second bus bar, and the dummy finger strip is connected to the plurality of metal strips disposed between the electrodes.
  • a resonator is also proposed, and the resonator includes: a silicon substrate and an energy trap layer disposed on the silicon substrate, a silicon dioxide layer, a piezoelectric single crystal layer, the IDT structure and the passivation layer disposed on the IDT structure.
  • a resonator manufacturing method is also proposed, and the resonator manufacturing method includes:
  • An interdigital transduction structure is arranged on the piezoelectric single crystal layer, and the first electrodes and the second electrodes of the interdigital transduction structure are connected by a plurality of metal strips;
  • a metal thickening layer is provided at the electrode end of each first electrode and at the lateral corresponding position of the second electrode adjacent to the first electrode;
  • a metal thickening layer is provided at the electrode end of each second electrode and at the corresponding position in the lateral direction of the first electrode adjacent to the second electrode;
  • a passivation layer is provided on the interdigital transducer structure.
  • the step of constructing a low-sonic silicon dioxide layer on the energy trapping layer comprises:
  • a low-sonic silicon dioxide layer is obtained by mechanically planarizing the initial silicon dioxide layer.
  • the interdigital transduction structure is provided on the piezoelectric single crystal layer, and a plurality of metal strips are passed between each first electrode and each second electrode of the interdigital transduction structure.
  • the steps to connect include:
  • first electrodes and second electrodes are sequentially spaced between the first bus bar and the second bus bar;
  • a plurality of metal strips are respectively arranged between each first electrode and each second electrode.
  • the step of arranging an interdigital transducer structure on the piezoelectric single crystal layer further includes:
  • a plurality of metal strips are respectively arranged between each first electrode and each second electrode.
  • a filter including the above-mentioned resonator is also proposed.
  • FIG. 1 is a structural schematic diagram of the first embodiment of the interdigital transducing structure of the present disclosure
  • FIG. 2 is a schematic diagram of the first structure of the second embodiment of the interdigital transducing structure of the present disclosure
  • FIG. 3 is a second structural schematic diagram of the second embodiment of the interdigital transducing structure of the present disclosure
  • Fig. 4 is a third structural schematic diagram of the second embodiment of the interdigital transducing structure of the present disclosure.
  • FIG. 5 is a schematic diagram of a fourth structure of the second embodiment of the interdigital transducing structure of the present disclosure.
  • FIG. 6 is a schematic diagram of a fifth structure of the second embodiment of the interdigital transducing structure of the present disclosure.
  • FIG. 7 is a schematic diagram of a sixth structure of the second embodiment of the interdigital transducing structure of the present disclosure.
  • FIG. 8 is a schematic diagram of a seventh structure of the second embodiment of the interdigital transducing structure of the present disclosure.
  • FIG. 9 is a schematic diagram of the eighth structure of the second embodiment of the interdigital transducing structure of the present disclosure.
  • Fig. 10 is a transverse cross-sectional view at the end of the electrodes of the first structure in the third embodiment of the interdigital transducing structure of the present disclosure
  • Fig. 11 is a longitudinal sectional view of electrodes of the first structure in the third embodiment of the interdigital transducing structure of the present disclosure
  • Fig. 12 is a transverse cross-sectional view at the end of the electrodes of the second structure in the third embodiment of the interdigital transducing structure of the present disclosure
  • Fig. 13 is a longitudinal sectional view of electrodes of the second structure in the third embodiment of the interdigital transducing structure of the present disclosure
  • Fig. 14 is a schematic diagram of the third structure of the third embodiment of the interdigital transducing structure of the present disclosure.
  • Fig. 15 is a schematic diagram of a third structure in the third embodiment of the interdigital transducing structure of the present disclosure.
  • FIG. 16 is a graph showing the change in admittance amplitude between the interdigital transduction structure and the conventional interdigital transduction structure in the third embodiment of the disclosed interdigital transduction structure;
  • Fig. 17 is a diagram showing the change of the real part of the admittance of the interdigital transduction structure in the third embodiment of the interdigital transduction structure of the present disclosure and the conventional interdigital transduction structure;
  • FIG. 19 is a Q value change diagram between the interdigital transduction structure and the conventional interdigital transduction structure in the third embodiment of the interdigital transduction structure of the present disclosure.
  • FIG. 20 is a schematic structural diagram of a resonator of the present disclosure.
  • FIG. 21 is a schematic flow chart of the first embodiment of the method for manufacturing a resonator according to the present disclosure
  • FIG. 22 is a schematic flow chart of the second embodiment of the resonator manufacturing method of the present disclosure.
  • FIG. 23 is a schematic flowchart of a third embodiment of the method for manufacturing a resonator of the present disclosure.
  • Metal strips 40 metal thickening 50 silicon substrate 60 energy trap layer 70 silica layer 80 Piezoelectric single crystal layer 90 passivation layer 101 first electrode 201 second electrode the the
  • FIG. 1 is a schematic structural diagram of an interdigital transducing structure proposed in the first embodiment of the present disclosure, as shown in FIG. 1 .
  • the IDT structure includes: a first bus bar 10 and a second bus bar 20 arranged in parallel, and a plurality of first electrodes 101 are arranged on the first bus bar 10 , and the first bus bar 10 A plurality of second electrodes 201 are arranged on the second bus bar 20 , and the plurality of first electrodes 101 and the plurality of second electrodes 201 are relatively spaced between the first bus bar 10 and the second bus bar 20 the middle area of
  • the middle region includes an interdigital area and a monopolar area that does not belong to the interdigital area, and the interdigital area is the end edge of the plurality of first electrodes 101 away from the first bus bar 10 and the a plurality of second electrodes 201 away from the region formed between the end edges of the second bus bar 20;
  • Each first electrode 101 and second electrode 201 in each unipolar region are connected by a plurality of metal strips.
  • the interdigital transduction structure may be a finger-shaped metal pattern formed on the surface of the piezoelectric substrate, and the interdigital transduction structure may be an interdigital transducer, which can be used to realize sound-to-electricity transduction.
  • the interdigital transduction structure can be set in the shape of a metal film, and the metal film can be formed of a single metal such as titanium, chromium, copper, silver, aluminum or a combination thereof.
  • the metal strip 30 is a metal structure for electrically shorting between the first electrodes 101 or between the second electrodes 201 .
  • the width of the metal strip 30 can be 1/8 to 1/2 times the periodic wavelength of the interdigital transduction structure, and the distance between the metal strips 30 can be the same as the width of the metal strip 30, that is, the interdigital transduction structure. 1/8 to 1/2 times the periodic wavelength. 2 to 15 metal strips may be arranged in the electrode gap between adjacent first electrodes 101 and the electrode gap between adjacent second electrodes 201 .
  • the interdigitated area is between the end edges of the plurality of first electrodes 101 away from the first bus bar 10 and the end edges of the plurality of second electrodes 201 away from the second bus bar 20 Area.
  • the unipolar region refers to the distance between the plurality of first electrodes 101 and the second bus bar 20 and the area between the plurality of second electrodes 201 and the first bus bar 10 .
  • the unipolar regions corresponding to the first electrodes 101 and the second electrodes 201 can be determined first, and then the first electrodes 101 in the unipolar region are connected by a plurality of metal strips 30, so that each first electrode 101
  • the second electrodes 201 are also connected by a plurality of metal strips 30, so that the second electrodes 201 are electrically shorted.
  • the surface acoustic wave filter can be grown on the composite multilayer material substrate and the transverse mode can be completely suppressed, and the Q value of the filter can be greatly improved. .
  • an interdigital transduction structure includes: a first bus bar and a second bus bar arranged in parallel, and a plurality of first electrodes are arranged on the first bus bar , the second bus bar is provided with a plurality of second electrodes, and the plurality of first electrodes and the plurality of second electrodes are arranged at intervals in the middle between the first bus bar and the second bus bar area; the middle area includes an interdigital area and a unipolar area that does not belong to the interdigital area, and the interdigital area is the end edge of the plurality of first electrodes away from the first bus bar and the A region formed between a plurality of second electrodes away from the end edges of the second busbar; in the unipolar region, each first electrode and each second electrode are connected by a plurality of metal strips.
  • each first electrode and each second electrode in the unipolar region through a plurality of metal strips, using a plurality of metal strips to short-circuit each electrode and setting a metal thickening layer, the use of The above structure makes the sound velocity in the monopolar region and the interdigital region different, thereby effectively suppressing the transverse mode ripple.
  • the unipolar region includes a first unipolar region and a second unipolar region, and a plurality of metal strips pass between adjacent first electrodes in the first unipolar region. Connecting each adjacent second electrode in the second unipolar region through a plurality of metal strips.
  • the first unipolar region is the region between the first bus bar 10 and the second electrode 201
  • the second unipolar region is the region between the second bus bar 20 and the first electrode 101 .
  • the first unipolar region includes part of the first electrodes 101 , and there is an electrode gap between adjacent first electrodes 101 .
  • Multiple metal strips can be arranged in each electrode gap, and the number of metal strips arranged in different electrode gaps can be the same or different. Referring to FIG. 2 , in FIG. 2 , different numbers of metal strips 30 are set between each gap as an example for illustration.
  • the same number can be set at regular intervals without passing through the number of metal strips 30 between the electrode gaps. Of course, it can also be set arbitrarily under the condition that the number of metal strips is satisfied, which is not done here. Specific limits. For example, in the first unipolar region, four metal strips and six metal strips are sequentially arranged in adjacent gaps at intervals.
  • the number of metal strips disposed between the adjacent first electrodes 101 and/or between the adjacent second electrodes 201 may be the same. Referring to Fig. 2, in the first unipolar region and the second unipolar region, compared with the electrode gap with four metal strips, there is still a certain space here that is not properly utilized, so , the same number of metal strips can be set in each electrode gap.
  • the metal strip 30 may be a rectangular metal strip or a trapezoidal metal strip.
  • the metal strips 30 are rectangular metal strips arranged in parallel, or rectangular metal strips arranged obliquely at a predetermined angle.
  • the preset angle is a preset inclination angle
  • the inclination angle needs to be selected as a smaller angle to ensure that the metal strip in the electrode gap is in the first unipolar region or the second unipolar region.
  • the inclination angle and inclination direction of the metal strips in different electrode gaps are not specifically limited.
  • the metal strips on both sides of the first electrode 101 and/or the second electrode 201 are aligned with the corresponding first electrode 101 and/or the second electrode 201. The same position on the first electrode 101 and/or the second electrode 201 is connected.
  • the metal strips on both sides of the electrodes can be connected at the same position of the electrodes.
  • the metal strips in the first unipolar region or the metal strips in the second unipolar region can be arranged separately, and the metal strips on both sides of the first electrode 101 in the first unipolar region are connected to the metal strips of the first electrode 101 respectively.
  • the same position is connected or the metal strips on both sides of the second electrode 201 in the second unipolar region are respectively connected to the same position of the second electrode 201 .
  • the metal strips on both sides of the electrodes in the first unipolar region and the second unipolar region can also be provided at the same time, which is not specifically limited here.
  • the metal strip 30 is a trapezoidal metal strip
  • the lower bottom edges of the metal strips connected to both sides of the first electrode 101 or the second electrode 201 point to the same or opposite direction to the upper bottom edge.
  • the metal strips 30 are all trapezoidal metal strips, and the width of the trapezoidal metal strips may be 1/8 to 1/2 times the periodic wavelength of the interdigital transducer structure, and the ladder The distance between the shaped metal strips may be the same as the width of the metal strip 30 , that is, 1/8 to 1/2 times the periodic wavelength of the IDT structure.
  • the metal strips 30 on both sides of the first electrode 101 and/or the second electrode 201 are alternately arranged on both sides of the corresponding first electrode 101 and/or on both sides of the second electrode 201 at the same distance. .
  • the metal strips 30 connected to both sides of the electrode can also be arranged in a staggered manner, and different metal strips are connected at different positions on the same electrode.
  • the metal strips on both sides of the same first electrode 101 in the first electrode region can be connected alternately, and the metal strips on both sides of the same electrode in the second unipolar region can be connected at the same position of the second electrode 201;
  • the metal strips on both sides of the same first electrode 101 in the first electrode region can be at the same position of the first electrode 101, and the metal strips on both sides of the same second electrode 201 in the second unipolar region can be at the same position on the first electrode 101.
  • Both sides of the two electrodes 201 are connected to each other in an interlaced manner.
  • the first electrodes 101 or the second electrodes 201 are connected through a plurality of metal strips; wherein each metal strip runs through each first electrode 101 or each second electrode 201. Two electrodes 201 .
  • the above-mentioned metal strips 30 are all metal strips arranged in the electrode gap between adjacent electrodes.
  • all the first electrodes 101 or All second electrodes 201 are directly connected.
  • a plurality of metal strips may directly penetrate each first electrode 101 or be attached to the surface of each first electrode 101 .
  • four metal strips 30 with longer lengths are set, and the metal strips can be directly attached to the surfaces of the first electrodes 101 or the second electrodes 201, and all the first electrodes 201 are connected in the first unipolar region.
  • One electrode 101 is connected so that all first electrodes 101 are electrically short-circuited; the same is true in the second unipolar region.
  • the plurality of metal strips 30 are metal strips that are inclined in the same direction and at the same angle. Considering that the inclination of the metal strips will directly lead to an increase in the area of the manufactured resonator chip, the inclination of the metal strips The angle should be within a certain bevel angle range, for example, 1°-3°.
  • the adjacent metal strips 30 can be rotated at a certain angle in different directions, and the metal strips can be cut obliquely, which can also effectively reduce the chip area of the resonator.
  • the number of metal strips will also increase the chip area of the resonator, so in this embodiment, it is optimal to set the number of metal strips between 2 and 8.
  • the thickened metal layer 40 is disposed on the upper surface or the lower surface of the first electrode 101 and the second electrode 201 .
  • the purpose of setting the metal thickening layer 40 in this embodiment is to form a piston mode between the unipolar region and the interdigital region.
  • the metal thickening layer 40 is arranged on the upper surface and the lower surface of the electrode Both surfaces may form a piston pattern between the first bus bar 10 and the second bus bar 20 . Therefore, the metal thickening layer 40 can be arranged on the upper surface of the corresponding electrode, and also can be arranged on the lower surface of the electrode. In FIG. 10 and FIG. 11 the metal thickening layer 40 is arranged on the upper surface of the first electrode 101 , and in FIG. 12 and FIG. 13 the metal thickening layer 40 is arranged on the lower surface of the first electrode 101 .
  • the metal thickening layer 40 disposed on the second electrode 201 may refer to the manner of disposing the metal thickening layer 40 on the first electrode 101 , which will not be repeated here.
  • a dummy finger bar is provided between the electrode gaps between the adjacent first electrodes and the electrode gaps between the adjacent second electrodes, and the dummy finger bar is connected to the first electrode gap.
  • An electrode or a second electrode is correspondingly arranged.
  • the dummy finger strip is connected to the first bus bar or the second bus bar, and the dummy finger bar is connected to the plurality of metal strips arranged between electrodes.
  • dummy finger strips may also be provided, wherein the dummy finger strips are arranged in the electrode gap between adjacent first electrodes 101 and the electrode gap between adjacent second electrodes 201 .
  • the dummy finger strips are correspondingly arranged with the first electrode 101 or the second electrode 201 at the corresponding position.
  • the dummy finger strip can be arranged on the outermost metal strip in the electrode gap, and of course the dummy finger strip can also be connected to the bus bar through all the metal strips in the electrode gap.
  • the Q value of the device can be further improved by using the false finger strip.
  • test results of the resonator of the interdigital transduction structure in this embodiment are the admittance amplitude and the real part of the admittance respectively.
  • test results of a resonator with a conventional surface acoustic wave interdigital transducer structure are added for comparison.
  • the solid lines represent conventionally designed resonators, and the dashed lines represent resonators of the disclosed design.
  • Fig. 18 is a Smith chart of the resonator composed of the interdigital transduction structure and the resonator composed of the conventional interdigital Huaneng structure in this embodiment, the same solid line represents the resonator of conventional design, and the dotted line represents the design of the present disclosure
  • the conventionally designed resonator has a lot of spurious peaks, but the resonator designed in this embodiment has no spurious peaks in the passband.
  • a metal thickening layer is arranged on the electrodes, so that the first busbar A piston mode is formed between the second bus bar, thereby more effectively suppressing the residual acoustic shear wave mode, reducing the clutter response of the surface acoustic wave transducer, and greatly reducing the in-band fluctuation of the surface acoustic wave transducer , lower insertion loss, better squareness coefficient, and higher quality factor, so the performance of the surface acoustic wave transducer is greatly improved.
  • the present disclosure also provides a resonator, which includes: a silicon substrate 50 and an energy trap layer 60 disposed on the silicon substrate, a silicon dioxide layer 70 , and a piezoelectric single crystal Layer 80, the IDT structure, and a passivation layer 90 disposed on the IDT structure.
  • FIG. 21 is a schematic flowchart of the first embodiment of the resonator manufacturing method of the present disclosure. Based on the above structure of the resonator, the first embodiment of the manufacturing method of the disclosed resonator is proposed.
  • the manufacturing method of the resonator includes:
  • Step S10 using high-resistance silicon to construct a resonator substrate
  • the resonator substrate first needs to be made, and the resonator substrate can be made of high-resistance materials.
  • high-resistance silicon can be selected as the substrate material to make the resonator substrate. end.
  • the high-resistance silicon can be P-type silicon or N-type silicon, and its resistivity is greater than 2000 ( ⁇ -cm), preferably greater than 10000 ( ⁇ -cm).
  • Step S20 using polysilicon to construct an energy trap layer on the resonator substrate;
  • the vertical direction of the current device is generally a MOS structure such as metal-silicon oxide-Si.
  • MOS structure such as metal-silicon oxide-Si.
  • Step S30 building a silicon dioxide layer with low sound velocity on the energy trap layer
  • Step S40 building a piezoelectric single crystal layer on the silicon dioxide layer by bonding
  • Step S50 setting an interdigital transduction structure on the piezoelectric single crystal layer, and connecting each first electrode and each second electrode of the interdigital transduction structure through a plurality of metal strips;
  • Step S60 setting a metal thickening layer at the electrode end of each first electrode and at the corresponding position in the lateral direction of the second electrode adjacent to the first electrode;
  • Step S70 setting a metal thickening layer at the electrode end of each second electrode and at the corresponding position in the lateral direction of the first electrode adjacent to the second electrode;
  • a metal thickening layer is provided at the electrode end of each first electrode and at the corresponding position in the lateral direction of the second electrode adjacent to the first electrode;
  • a metal thickening layer is provided at the corresponding positions in the lateral direction of the electrode end and the first electrode adjacent to the second electrode.
  • the surface acoustic wave transducer forms between the interdigital area and the first electrode area, and between the interdigital area and the second electrode area.
  • Piston mode that is, the sound velocity at the edge of the interdigitated region is lower than the sound velocity at the center of the interdigitated region, and the sound velocity of the first and second single-fingered regions is higher than the sound velocity at the center of the interdigitated region, thereby suppressing the residual acoustic shear wave mode .
  • Step S80 setting a passivation layer on the IDT structure.
  • the piezoelectric material of the piezoelectric single crystal layer can be LiTaO3 (lithium tantalate) and LiNbO3 (lithium niobate), wherein the cutting angle of LiTaO3 (lithium tantalate) can be 30°, 42°, 50°, and the thickness is between (300- 1000nm) range.
  • the interdigital transduction structure can be set on the piezoelectric single crystal layer, wherein adjacent electrodes of the interdigital transduction structure are electrically connected by a plurality of metal strips.
  • an anti-corrosion passivation layer may also be provided on the interdigital transduction structure.
  • the passivation layer can be made using silicon dioxide (SiO2) and silicon nitride (Si3N4).
  • a method for manufacturing a transducer In this embodiment, a method for manufacturing a transducer is provided.
  • a plurality of metal strips are arranged between each first electrode and each second electrode of the interdigital transducer structure, and a plurality of metal bars The strip electrically shorts each first electrode and each second electrode to effectively suppress transverse mode ripple.
  • FIG. 22 is a schematic flowchart of a second embodiment of the resonator manufacturing method of the present disclosure. Based on the first embodiment of the resonator manufacturing method described above, a second embodiment of the disclosed resonator manufacturing method is proposed.
  • step S30 specifically includes:
  • Step S301 building an initial silicon dioxide layer on the energy trap layer by vapor deposition or thermal oxidation
  • Step S302 performing mechanical planarization on the initial silicon dioxide layer to obtain a low-sonic silicon dioxide layer.
  • the material of the silicon dioxide layer can be fixed on the energy trap layer by means of plasma-enhanced chemical vapor deposition or thermal oxidation to form an initial silicon dioxide layer. layer. Then chemical mechanical planarization is performed on the initial silicon dioxide layer, and the thickness of the initial silicon dioxide layer is controlled within the range of 300-800nm to form a silicon dioxide layer.
  • Described step S50 comprises:
  • Step S501 setting a first bus bar and a second bus bar on the piezoelectric single crystal layer according to a preset positional relationship
  • the preset position is a preset position used to prevent the first bus bar from meeting the second bus bar.
  • two positions can be selected as preset positions on the piezoelectric single crystal layer according to the positional relationship of the bus bars. Then place the first bus bar and the second bus bar according to the preset position.
  • Step S502 arranging a plurality of first electrodes and second electrodes at intervals between the first bus bar and the second bus bar;
  • first electrodes and second electrodes may be disposed on the first bus bar and the second bus bar.
  • the first electrode is arranged on the first bus bar
  • the second electrode is arranged on the second bus bar
  • an interdigitated electrode structure is formed between the first electrode and the second electrode.
  • Step S503 setting a plurality of metal strips between each first electrode and each second electrode respectively.
  • the metal thickening layer can be arranged at the electrode end of the first electrode away from the first bus bar and at the corresponding position in the lateral direction of the second electrode adjacent to the first electrode.
  • the first electrode is provided with two metal Thickening layer completes the metal thickening layer arrangement of the first electrode.
  • the metal thickening layer also needs to be arranged at the electrode end of the second electrode away from the second bus bar and at the corresponding position in the lateral direction of the first electrode adjacent to the second electrode, so as to complete the metal thickening layer on the second electrode setting.
  • a metal thickening layer is arranged on the electrodes, so that the first bus bar and the second electrode can be electrically shorted.
  • a piston mode is formed between the second busbars, thereby more effectively suppressing the residual acoustic shear wave mode, reducing the clutter response of the surface acoustic wave transducer, and greatly reducing the in-band fluctuation of the surface acoustic wave transducer. With reduced insertion loss, better squareness factor and higher quality factor, the performance of SAW transducers is greatly improved.
  • FIG. 23 is a schematic flowchart of a third embodiment of the resonator manufacturing method of the present disclosure. Based on the first embodiment of the resonator manufacturing method described above, a third embodiment of the disclosed resonator manufacturing method is proposed.
  • step S50 also includes:
  • Step S51 setting a metal thickening layer on the piezoelectric single crystal layer
  • the thickened metal layer may be provided first, and then the first electrode and the second electrode at corresponding positions may be arranged according to the thickened metal layer.
  • the specific position of the metal thickening layer should be determined. In order to avoid other structures outside the piezoelectric single crystal layer, the position close to the center of the piezoelectric single crystal layer should be selected as the metal thickening layer. layer location, and place the metal thickening layer on that location.
  • Step S52 setting the first electrode and the second electrode according to the position information of the metal thickening layer
  • Step S53 setting a first bus bar and a second bus bar according to the first electrode and the second electrode;
  • Step S54 arranging a plurality of metal strips between the first electrodes and between the second electrodes respectively.
  • first electrode and the second electrode can be directly arranged at corresponding positions. Then, according to the accurate positions of the first electrodes and the second electrodes, corresponding first bus bars and second bus bars are set. Finally, a plurality of metal strips are arranged in the electrode gaps between the first electrodes and the second electrodes, so as to complete the construction of the IDT structure.
  • the present disclosure also provides a filter, which includes the above resonator.
  • a filter which includes the above resonator.
  • the filter adopts all the technical solutions of the above-mentioned embodiments, it at least has all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, and will not repeat them here.

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  • Acoustics & Sound (AREA)
  • Surface Acoustic Wave Elements And Circuit Networks Thereof (AREA)

Abstract

本公开公开了一种叉指换能结构、谐振器、谐振器制作方法及滤波器，涉及谐振器领域，该叉指换能结构包括：平行设置的第一汇流排(10)和第二汇流排(20)，第一汇流排(10)上设置有多个第一电极(101)、第二汇流排(20)上设置有多个第二电极(201)，多个第一电极(101)和多个第二电极(201)相对间隔设置在第一汇流排(10)和第二汇流排(20)之间的中间区域；中间区域包含叉指区和不属于所述叉指区的单极区；单极区中各第一电极(101)之间和各第二电极(201)之间通过多个金属条(30)连接，并在各电极的电极端以及对应电极处设置金属加厚层。

Description

叉指换能结构、谐振器、谐振器制作方法及滤波器
相关申请的交叉引用
本公开要求于2022年01月28日提交中国专利局、申请号为202210103998.2、发明名称为“叉指换能结构、谐振器、谐振器制作方法及滤波器”的中国专利申请的优先权，其全部内容通过引用结合在本公开中。
技术领域
本公开涉及谐振器技术领域，尤其涉及一种叉指换能结构、谐振器、谐振器制作方法及滤波器。
背景技术
随着通信技术从2G发展至5G，通信频段数目逐步增加。为了提高智能手机对不同通信制式的兼容能力，5G智能手机所需要的滤波器用量将显著上升，推动滤波器市场大规模增长。无线通信终端中目前广泛应用的射频滤波器是声表滤波器，负责接收和发射通道的射频信号滤波，将输入的多种射频信号中特定频率的信号输出。同时，随着移动通讯技术的持续发展和射频前端模组化发展，高端应用的普及对滤波器和谐振器的需求趋向复杂化，高端化，小型化。
基于具有薄膜形式的压电材料的高性能声表滤波器技术制作的谐振器，该谐振器组成的射频滤波器，实现低插损，通带平滑，高Q值(Q值为电感器件在某一频率下，感抗与等效损耗电阻之比)以及出色的低频率温度等特性。
高性能声表面波谐振器是一种相对新型的谐振器，由于其压电材料为复合多层材料键合而成，声波的传播及工作模式不同于常规声表面波谐振器，如果仍然采用常规声表面波谐振器的设计方法设计出的和射频滤波器会出现很强的横向模式波纹，通带杂波严重，将会导致整体器件性能的恶化。
上述内容仅用于辅助理解本公开的技术方案，并不代表承认上述内容是现有技术。
发明内容
根据本公开的各种实施例，提供一种叉指换能结构、谐振器、谐振器制作方法及滤波器。
根据本公开的各种实施例，提出一种叉指换能结构，所述叉指换能结构包括：平行设置的第一汇流排和第二汇流排，所述第一汇流排上设置有多个第一电极、所述第二汇流排上设置有多个第二电极，所述多个第一电极和所述多个第二电极相对间隔设置在所述第一汇流排和第二汇流排之间的中间区域；
所述中间区域包含叉指区和不属于所述叉指区的单极区，所述叉指区为所述多个第一电极远离所述第一汇流排的端部边缘和所述多个第二电极远离所述第二汇流排的端部边缘之间形成的区域；
单极区中各第一电极之间和各第二电极之间通过多个金属条连接；
在所述叉指区内，各第一电极的电极端以及与所述第一电极相邻的第二电极的横向对应位置处设置金属加厚层；
各第二电极的电极端以及与所述第二电极相邻的第一电极的横向对应位置处设置金属加厚层。
在一些实施例中，所述单极区包括第一单极区和第二单极区，在所述第一单极区内各相邻第一电极之间通过多个金属条连接，在所述第二单极区内各相邻第二电极之间通过多 个金属条连接。
在一些实施例中，所述各相邻第一电极之间和/或各相邻第二电极之间设置的金属条数目相同。
在一些实施例中，所述金属条为平行设置的矩形状金属条，或倾斜预设角度设置的矩形状金属条。
在一些实施例中，在切斜预设角度设置的矩形状金属条中，所述第一电极和/或所述第二电极两侧的金属条与对应的所述第一电极和/或第二电极上相同的位置连接。
在一些实施例中，所述金属条为梯形状金属条时，第一电极两侧或第二电极两侧连接的金属条的下底边指向上底边的方向相同或相反。
在一些实施例中，所述第一电极和/或所述第二电极两侧的金属条间隔相同距离交错设置在对应的所述第一电极两侧和/或第二电极两侧。
在一些实施例中，所述第一电极之间或所述第二电极之间通过多个金属条贯穿连接；其中各金属条均贯穿各第一电极或各第二电极。
在一些实施例中，所述金属加厚层设置在所述第一电极和所述第二电极的上表面或下表面。
在一些实施例中，所述假指条与所述第一汇流排或所述第二汇流排连接，所述假指条与电极之间设置的所述多个金属条连接。
根据本公开的各种实施例，还提出一种谐振器，所述谐振器包括：硅衬底和以此设置在所述硅衬底上的能量陷阱层、二氧化硅层、压电单晶层、所述的叉指换能结构以及设置在所述叉指换能结构上的钝化层。
根据本公开的各种实施例，还提出一种谐振器制作方法，所述谐振器制作方法包括：
利用高阻硅构建谐振器衬底；
利用多晶硅在所述谐振器衬底上构建能量陷阱层；
在所述能量陷阱层上构建低声速的二氧化硅层；
通过键合方式在所述二氧化硅层上构建压电单晶层；
在所述压电单晶层上设置叉指换能结构，所述叉指换能结构的各第一电极之间和各第二电极之间通过多个金属条连接；
在各第一电极的电极端以及与所述第一电极相邻的第二电极的横向对应位置处设置金属加厚层；
在各第二电极的电极端以及与所述第二电极相邻的第一电极的横向对应位置处设置金属加厚层；
在所述叉指换能结构上设置钝化层。
在一些实施例中，所述在所述能量陷阱层上构建低声速的二氧化硅层的步骤包括：
通过气相沉积或热氧化方式在所述能量陷阱层上构建初始二氧化硅层；
对所述初始二氧化硅层进行机械平坦化处理获得低声速的二氧化硅层。
在一些实施例中，所述在所述压电单晶层上设置叉指换能结构，所述叉指换能结构的各第一电极之间和各第二电极之间通过多个金属条连接的步骤包括：
在所述压电单晶层上根据预设位置关系设置第一汇流排和第二汇流排；
在所述第一汇流排和所述第二汇流排之间依次间隔设置多个第一电极和第二电极；
分别在各第一电极之间和各第二电极之间设置多个金属条。
在一些实施例中，所述在所述压电单晶层上设置叉指换能结构的步骤还包括：
在所述压电单晶层上设置金属加厚层；
根据所述金属加厚层的位置信息设置第一电极和第二电极；
根据所述第一电极和所述第二电极设置第一汇流排和第二汇流排；
分别在各第一电极之间和各第二电极之间设置多个金属条。
根据本公开的各种实施例，还提出一种滤波器，所述滤波器包括上述谐振器。
本公开的一个或多个实施例的细节在下面的附图和描述中提出。本公开的其他特征、目的和优点将从说明书、附图以及权利要求书变得明显。
附图说明
为了更清楚地说明本公开实施例中的技术方案，下面将对实施例中所需要使用的附图作简单地介绍，显而易见地，下面描述中的附图仅仅是本公开的一些实施例，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据这些附图示出的结构获得其他的附图。
图1为本公开叉指换能结构第一实施例的结构示意图；
图2为本公开叉指换能结构第二实施例的第一种结构示意图；
图3为本公开叉指换能结构第二实施例的第二种结构示意图；
图4为本公开叉指换能结构第二实施例的第三种结构示意图；
图5为本公开叉指换能结构第二实施例的第四种结构示意图；
图6为本公开叉指换能结构第二实施例的第五种结构示意图；
图7为本公开叉指换能结构第二实施例的第六种结构示意图；
图8为本公开叉指换能结构第二实施例的第七种结构示意图；
图9为本公开叉指换能结构第二实施例的第八种结构示意图；
图10为本公开叉指换能结构第三实施例中第一种结构的电极的端头处的横向剖面图；
图11为本公开叉指换能结构第三实施例中第一种结构的电极的纵向剖面图；
图12为本公开叉指换能结构第三实施例中第二种结构的电极的端头处的横向剖面图；
图13为本公开叉指换能结构第三实施例中第二种结构的电极的纵向剖面图；
图14为本公开叉指换能结构第三实施例中第三种结构示意图；
图15为本公开叉指换能结构第三实施例中第三种结构示意图；
图16为本公开叉指换能结构第三实施例中的叉指换能结构与常规叉指换能结构的导纳幅值变化曲线图；
图17为本公开叉指换能结构第三实施例中的叉指换能结构与常规叉指换能结构的导纳实部曲线变化图；
图18为本公开叉指换能结构第三实施例中的叉指换能结构与常规叉指换能结构的史密斯圆图；
图19为本公开叉指换能结构第三实施例中的叉指换能结构与常规叉指换能结构的Q值变化图；
图20为本公开谐振器的结构示意图；
图21为本公开谐振器制作方法第一实施例的流程示意图；
图22为本公开谐振器制作方法第二实施例的流程示意图；
图23为本公开谐振器制作方法第三实施例的流程示意图。
附图标号说明：
标号 名称 标号 名称
10 第一汇流排 20 第二汇流排
30 金属条 40 金属加厚层
50 硅衬底 60 能量陷阱层
70 二氧化硅层 80 压电单晶层
90 钝化层 101 第一电极
201 第二电极    
为了更好地描述和说明这里公开的那些发明的实施例和/或示例，可以参考一幅或多幅附图。用于描述附图的附加细节或示例不应当被认为是对所公开的发明、目前描述的实施例和/或示例以及目前理解的这些发明的最佳模式中的任何一者的范围的限制。
具体实施方式
应当理解，此处所描述的具体实施例仅仅用以解释本公开，并不用于限定本公开。
下面将结合本公开实施例中的附图，对本公开实施例中的技术方案进行清楚、完整地描述。
参照图1，图1为本公开第一实施例提出叉指换能结构的结构示意图，如图1所示。
在本实施例中，所述叉指换能结构包括：平行设置的第一汇流排10和第二汇流排20，所述第一汇流排10上设置有多个第一电极101、所述第二汇流排20上设置有多个第二电极201，所述多个第一电极101和所述多个第二电极201相对间隔设置在所述第一汇流排10和第二汇流排20之间的中间区域；
所述中间区域包含叉指区和不属于所述叉指区的单极区，所述叉指区为所述多个第一电极101远离所述第一汇流排10的端部边缘和所述多个第二电极201远离所述第二汇流排20的端部边缘之间形成的区域；
各单极区中各第一电极101和第二电极201之间通过多个金属条连接。
需要说明的是，叉指换能结构可以是在压电基片表面上形成手指交叉状的金属图案，叉指换能结构就可以为叉指换能器，可用于实现声至电换能。叉指换能结构可以设置为金属薄膜形状，该金属薄膜可以由钛、铬、铜、银、铝等单个金属或者它们的组合形成。金属条30是用于将各第一电极101之间或各第二电极201之间进行电短路的金属结构。该金属条30的宽度可以为叉指换能结构的1/8至1/2倍的周期波长，各金属条30之间的间隔距离可以与金属条30的宽度相同即叉指换能结构的1/8至1/2倍的周期波长。相邻第一电极101之间的电极间隙与相邻第二电极201之间的电极间隙内可以设置2个至15个金属条。
应理解的是，叉指区为所述多个第一电极101远离所述第一汇流排10的端部边缘与多个第二电极201远离所述第二汇流排20的端部边缘之间的区域。处于叉指区内的指相互交错设置的第一电极101和第二电极201在垂直于汇流排方向上的投影重合。单极区是指多个第一电极101与第二汇流排20之间的间隔距离以及多个第二电极201与第一汇流排10之间的区域。在第一汇流排10和第二汇流排20之间存在一个叉指区和两个单极区，叉指区处于两个单极区之间。
在具体实施中，可以首先确定第一电极101与第二电极201分别对应的单极区，然后将单极区内的各第一电极101通过多个金属条30连接，使各第一电极101之间电短路，当然第二电极201同样通过多个金属条30连接，使各第二电极201之间电短路。在同时 利用上述多金属条和金属加厚层的情况下，即可在复合多层材料衬底上生长声表面波滤波器且对横向模式进行完全抑制，进而可以大幅度提高滤波器的Q值。
在本实施例中提供了一种叉指换能结构，该叉指换能结构包括：平行设置的第一汇流排和第二汇流排，所述第一汇流排上设置有多个第一电极、所述第二汇流排上设置有多个第二电极，所述多个第一电极和所述多个第二电极相对间隔设置在所述第一汇流排和第二汇流排之间的中间区域；所述中间区域包含叉指区和不属于所述叉指区的单极区，所述叉指区为所述多个第一电极远离所述第一汇流排的端部边缘和所述多个第二电极远离所述第二汇流排的端部边缘之间形成的区域；单极区中各第一电极之间和各第二电极之间通过多个金属条连接。在本实施例中通过将单极区中各第一电极之间和各第二电极之间通过多个金属条连接，利用多条金属条使各电极之间短路以及设置金属加厚层，利用上述结构使单极区和叉指区声速不同，从而对横向模式波纹进行有效抑制。
基于上述叉指换能结构的第一实施例，提出本公开叉指换能结构的第二实施例。
参照图2，在本实施例中，所述单极区包括第一单极区和第二单极区，在所述第一单极区内各相邻第一电极之间通过多个金属条连接，在所述第二单极区内各相邻第二电极之间通过多个金属条连接。
应理解的是，第一单极区为第一汇流排10与第二电极201之间的区域，第二单极区为第二汇流排20与第一电极101之间的区域。第一单极区内包括部分第一电极101，相邻的第一电极101之间存在电极间隙。在每个电极间隙内可以设置多个金属条，不同的电极间隙内设置的金属条的数目可以相同也可以不同。参照图2，在图2中以各间隙之间设置不同数目的金属条30为例进行说明。在第一单极区内可以不通过电极间隙之间的金属条30的数目就可以采用一定的规律间隔设置相同的数目，当然也可以在满足金属条数目的情况下随意设置，此处不做具体限定。例如在第一单极区内采用四个金属条和六个金属条依次间隔设置在相邻间隙。
应理解的是，在考虑到整体面积利用效率，可以将所述各相邻第一电极101之间电极间隙和/或各相邻第二电极201之间设置的金属条数目相同。参照图2，在第一单极区和第二单极区内，设置三个金属条的电极间隙与设置四个金属条的电极间隙相比，此处还存在一定的空间未合理利用，因此，可以将各个电极间隙内设置相同数目的金属条。
参照图2至图4，在本实施例中，金属条30可以为矩形状金属条或梯形状金属条。所述金属条30为平行设置的矩形状金属条，或倾斜预设角度设置的矩形状金属条。
需要说明的是，预设角度是预先设定的倾斜角度，该倾斜角度需要选取一个较小的角度，以保证电极间隙内的金属条处于第一单极区或第二单极区内。此外在不同的电极间隙内金属条的倾斜角度和倾斜方向均不做具体限定。
参照图4，在本实施例中，在切斜预设角度设置的矩形状金属条中，所述第一电极101和/或所述第二电极201两侧的金属条与对应的所述第一电极101和/或第二电极201上相同的位置连接。
需要说明的是，在不同的电极两侧设置的金属条时，可以将电极两侧的金属条连接在该电极的相同位置。其中，可以将第一单极区内的金属条或第二单极区内的金属条单独设置，将第一单极区内的第一电极101两侧的金属条分别与第一电极101的相同位置连接或第二单极区内的第二电极201两侧的金属条分别与第二电极201的相同位置连接。当然还可以将第一单极区和第二单极区内的电极两侧的金属条同时设置，此处不做具体限定。
参照图5和图6，所述金属条30为梯形状金属条时，第一电极101两侧或第二电极201两侧连接的金属条的下底边指向上底边的方向相同或相反。
应理解的是，在图5和图6中金属条30均为梯形状金属条，该梯形状金属条的宽度可以为叉指换能结构的1/8至1/2倍的周期波长，梯形状金属条之间的间隔距离可以与金 属条30的宽度相同即叉指换能结构的1/8至1/2倍的周期波长。
参照图7，所述第一电极101和/或所述第二电极201两侧的金属条30间隔相同距离交错设置在对应的所述第一电极101两侧和/或第二电极201两侧。
应理解的是，在本实施例中，电极两侧连接的金属条30同样可以相互错开设置，不同的金属条在同一电极上连接的位置并不相同。其中，第一电极区内同一第一电极101两侧的金属条可以相互交错连接，而在第二单极区内的同一电极两侧的金属条可以连接在该第二电极201的相同位置；同理，第一电极区内同一第一电极101两侧的金属条可以在第一电极101相同位置，而在第二单极区内的同一第二电极201两侧的金属条可以在该第二电极201的两侧相互交错连接。
参照图8和图9在本实施例中，所述第一电极101之间或所述第二电极201之间通过多个金属条贯穿连接；其中各金属条均贯穿各第一电极101或各第二电极201。
应理解的是，上述金属条30均为设置在相邻电极的电极间隙内的金属条，在本实施例中，可以直接通过多个长度较长的金属条直接将所有的第一电极101或所有的第二电极201直接连接。此处多个金属条可以直接贯穿各第一电极101或附着在各第一电极101的表面。例如在图8和图9中设置4各长度较长的金属条30，该金属条可以直接附着在各第一电极101或第二电极201的表面，在第一单极区内将所有的第一电极101连接，使所有的第一电极101之间形成电短路；在第二单极区内同样如此。
需要说明的是，在图8中多个金属条30的为同一方向倾斜相同角度设置的金属条，考虑到金属条倾斜会直接导致制作出的谐振器芯片面积增大，因此该金属条倾斜的角度应当处于一定的切斜角度范围内，例如1°～3°即可。在图9中可以将相邻的金属条30之间以不同的方向旋转一定的角度设置，技能将该金属条切斜设置，还可以有效的降低谐振器芯片面积。此外金属条的数目同样会使谐振器芯片面积增大，因此在本实施例中，设置金属条的数目在2至8个之间最佳。
基于上述叉指换能结构的第一实施例和第二实施例，提出本公开叉指换能结构的第三实施例。
在本实施例中，所述金属加厚层40设置在所述第一电极101和所述第二电极201的上表面或下表面。
应理解的是，在本实施例中设置金属加厚层40的目的是在单极区与叉指区之间形成活塞模式，此时将该金属加厚层40设置在电极的上表面和下表面均可以在第一汇流排10与第二汇流排20之间形成活塞模式。因此该金属加厚层40既可以设置在对应电极的上表面，同样也可以设置在该电极的下表面。在图10和图11中该金属加厚层40设置在第一电极101的上表面，在图12和图13中该金属加厚层40设置在第一电极101的下表面。在第二电极201上设置的金属加厚层40可以参照第一电极101上金属加厚层40的设置方式，此处不再赘述。
参照图14，在本实施例中，相邻的各第一电极之间的电极间隙和相邻的各第二电极之间的电极间隙之间设有假指条，所述假指条与第一电极或第二电极对应设置。参照图15，所述假指条与所述第一汇流排或所述第二汇流排连接，所述假指条与电极之间设置的所述多个金属条连接。
应理解的是，在本实施例中还可以设置假指条，其中，假指条设置在相邻第一电极101之间的电极间隙以及相邻第二电极201之间的电极间隙内。假指条与对应位置的第一电极101或第二电极201之间对应设置。假指条可以设置在电极间隙内最外侧的金属条上，当然假指条也可以通过电极间隙内的所有金属条与汇流排连接。利用该假指条可以进一步提升器件的Q值。
参照16和图17，本实施例叉指换能结构的谐振器测试结果，分别为导纳幅值和导纳 实部。同时，为了更好的说明本公开的优势，加入了常规声表面波叉指换能结构的谐振器的测试结果作为对比。图16和图17中，实线表示常规设计的谐振器，虚线表示本公开设计的谐振器。当采用常规设计制作的谐振器通带内会有杂波，尤其在实部曲线可以看到，通带内杂波很严重；而采用本公开制作的谐振器能很好的抑制杂波，进而可以大幅度提高滤波器的损耗。参照图18，图18为本实施例中叉指换能结构组成的谐振器以及常规叉指华能结构组成的谐振器的史密斯圆图，同样实线表示常规设计的谐振器，虚线表示本公开设计的谐振器，常规设计的谐振器杂峰很多，而本实施例设计的谐振器通带内无杂峰。参照图19所示为两种谐振器的Q值的对比，实线表示常规设计的谐振器，虚线表示本实施例设计的谐振器，该图就可以特别直观的表示，本实施例设计的谐振器Q值接近4000，而常规设计的谐振器Q值只有3000左右。
在本实施例例中，在单极区内的设置多个金属条将各第一电极和各第二电极进行电短路的基础上，在电极上设置金属加厚层，可以在第一汇流排与第二汇流排之间形成活塞模式，从而更加有效的抑制残留的声波横波模式，降低了声表面波换能器的杂波响应，使得声表面波换能器的带内波动大幅度减小、插入损耗降低、矩形系数更佳、品质因数更高，因此声表面波换能器的性能大幅提高。
参照图20，本公开还提供一种谐振器，所述谐振器包括：硅衬底50和以此设置在所述硅衬底上的能量陷阱层60、二氧化硅层70、压电单晶层80、所述的叉指换能结构以及设置在所述叉指换能结构上的钝化层90。
参照图21，图21为本公开谐振器制作方法提出的第一实施例的流程示意图。基于上述谐振器的结构，提出本公开谐振器制作方法的第一实施例。
在本实施例中，所述谐振器制作方法包括：
步骤S10：利用高阻硅构建谐振器衬底；
需要说明的是，在谐振器制作过程中首先需要制作谐振器衬底，谐振器衬底可以通过高阻态的材料制作，在本实施例中可以选取高阻硅为衬底材料制作谐振器衬底。高阻硅可以为P型硅或者N型硅，其电阻率大于2000(Ω-cm)，优选其电阻率大于10000(Ω-cm)。
步骤S20：利用多晶硅在所述谐振器衬底上构建能量陷阱层；
应理解的是，目前的器件纵向一般就是金属-氧化硅-Si等MOS结构，在器件表面施加电压后会在SiO2/Si界面形成大量的电荷，叫做寄生表面电导，这样就会降低衬底的有效电阻率。增加能量陷阱层之后，因为多晶硅的缺陷非常多，这样就可以捕获这些寄生电荷，从而抑制了有效电阻的下降，能量就可以更好的被抑制在衬底表面可以进一步提升Q值，因此，在衬底制备完成后，可以在该衬底上制备一层能量陷阱层，该能量陷阱层可以由多晶硅材料组成。
步骤S30：在所述能量陷阱层上构建低声速的二氧化硅层；
步骤S40：通过键合方式在所述二氧化硅层上构建压电单晶层；
步骤S50：在所述压电单晶层上设置叉指换能结构，所述叉指换能结构的各第一电极之间和各第二电极之间通过多个金属条连接；
步骤S60：在各第一电极的电极端以及与所述第一电极相邻的第二电极的横向对应位置处设置金属加厚层；
步骤S70：在各第二电极的电极端以及与所述第二电极相邻的第一电极的横向对应位置处设置金属加厚层；
在本实施例中，在所述叉指区内，各第一电极的电极端以及与所述第一电极相邻的第二电极的横向对应位置处设置金属加厚层；各第二电极的电极端以及与所述第二电极相邻的第一电极的横向对应位置处设置金属加厚层。
应理解的是，采用实施例一和实施例二的叉指换能结构，即仅在靠近汇流条的地方增加各种样式的金属条会在一定程度上起到抑制横向模式的效果，但并不足以对横向模式进行完全抑制，还存在部分横向模式波形残留。此时可以在每个电极上设置两个金属加厚层，该金属加厚层可以将横行模式锁定在电极两个金属加厚层之间。
需要说明的是，通过在电极上设置两个金属加厚层，使得声表面波换能器的叉指区和第一电极区之间、叉指区和第二电极区之间形成声波传播的活塞模式，也就是叉指区边缘的声速低于叉指区中心的声速，并且第一单指区和第二单指区的声速高于叉指区中心的声速，从而抑制残留的声波横波模式。
步骤S80：在所述叉指换能结构上设置钝化层。
应理解的是，在能量陷阱层构建完成后，还需要在能量陷阱层上制备一层低声速的二氧化硅层，并在该二氧化硅层上构建压电单晶层。压电单晶层的压电材料可以是LiTaO3(钽酸锂)和LiNbO3(铌酸锂)，其中LiTaO3(钽酸锂)切角可以是30°，42°，50°，厚度在(300-1000nm)范围内。在压电单晶层构建完成后可以在压电单晶层上设置所述的叉指换能结构，其中该叉指换能结构的相邻电极之间用过多个金属条电连接。在该叉指换能结构设置完成后，为了避免该叉指换能结构上的金属被腐蚀，还可以在该叉指换能结构上设置一层防腐蚀的钝化层。该钝化层可以使用二氧化硅(SiO2)和氮化硅(Si3N4)制作。
在本实施例中提供了一种换能器制作方法，该换能器制作方法通过在叉指换能结构的各第一电极和各第二电极之间设置多个金属条，通过多个金属条将各第一电极和各第二电极电短路对横向模式波纹进行有效抑制。
参照图22，图22为本公开谐振器制作方法提出的第二实施例的流程示意图。基于上述谐振器制作方法的第一实施例，提出本公开谐振器制作方法的第二实施例。
在本实施例中，所述步骤S30具体包括：
步骤S301：通过气相沉积或热氧化方式在所述能量陷阱层上构建初始二氧化硅层；
步骤S302：对所述初始二氧化硅层进行机械平坦化处理获得低声速的二氧化硅层。
应理解的是，在二氧化硅层制作过程中可以利用等离子体增强化学的气相沉积法的方式或者热氧化的方式将二氧化硅层材料固定在所述能量陷阱层上，形成初始二氧化硅层。然后对该初始二氧化硅层的进行化学机械平坦化处理，将初始二氧化硅层的厚度控制在300-800nm范围内形成二氧化硅层。
所述步骤S50包括：
步骤S501：在所述压电单晶层上根据预设位置关系设置第一汇流排和第二汇流排；
需要说明的是，预设位置是预先设定的用于防止第一汇流排和第二会牛排的位置。在压电单晶层设置完成后，可以在压电单晶层上按照汇流排的位置关系选取两个位置作为预设位置。然后根据该预设位置放置第一汇流排和第二汇流排。
步骤S502：在所述第一汇流排和所述第二汇流排之间依次间隔设置多个第一电极和第二电极；
应理解的是，在第一汇流排和第二汇流排放置完成之后，可以在该第一汇流排和第二汇流排上设置多个第一电极和第二电极。第一电极设置在第一汇流排上，第二电极设置在第二汇流排上，第一电极与第二电极之间形成叉指电极结构。
步骤S503：分别在各第一电极之间和各第二电极之间设置多个金属条。
可以理解的是，在电极设置完成后需要在相邻的第一电极和相邻的第二电极之间的电极间隙内设置多个金属条，将各第一电极电短路连接以及将各第二电极电短路连接，降低声波的横波模式。
应理解的是，在第一电极和第二电极以及金属条均设置完成后，为了进一步降低恒波模式，还需要在第一电极和第二电极上设置金属加厚层。该金属加厚层可以设置在第一电 极远离第一汇流排的电极端以及与所述第一电极相邻的第二电极的横向对应位置处，此时该第一电极上设置有两个金属加厚层，完成该第一电极的金属加厚层设置。同理该金属加厚层还需要设置在第二电极远离第二汇流排的电极端以及与所述第二电极相邻的第一电极的横向对应位置处，完成第二电极上金属加厚层的设置。
在本实施例中，在单极区内的设置多个金属条将各第一电极和各第二电极进行电短路的基础上，在电极上设置金属加厚层，可以在第一汇流排与第二汇流排之间形成活塞模式，从而更加有效的抑制残留的声波横波模式，降低了声表面波换能器的杂波响应，使得声表面波换能器的带内波动大幅度减小、插入损耗降低、矩形系数更佳、品质因数更高，因此声表面波换能器的性能大幅提高。
参照图23，图23为本公开谐振器制作方法提出的第三实施例的流程示意图。基于上述谐振器制作方法的第一实施例，提出本公开谐振器制作方法的第三实施例。
在本实施例中，所述步骤S50还包括：
步骤S51：在所述压电单晶层上设置金属加厚层；
应理解的是，在叉指换能结构构建过程中，可以优先设置金属加厚层，然后根据该金属加厚层设置对应位置的第一电极和第二电极。其中，在金属加厚层设置过程中，要确定该金属加厚层的具体位置，为了避免其他结构处于压电单晶层外部，应当选取接近压电单晶层中心的位置作为该金属加厚层的位置，然后在该位置上设置金属加厚层。
步骤S52：根据所述金属加厚层的位置信息设置第一电极和第二电极；
步骤S53：根据所述第一电极和所述第二电极设置第一汇流排和第二汇流排；
步骤S54：分别在各第一电极之间和各第二电极之间设置多个金属条。
可以理解的是，在金属加厚层的位置固定之后，该第一电极和第二电极的位置便已经固定，此时便可以直接将该第一电极和第二电极设置在对应位置即可。然后根据该第一电极和第二电极的准确位置设置对应的第一汇流排和第二汇流排。最后在各第一电极之间和各第二电极之间的电极间隙内设置多个金属条，从而完成该叉指换能结构的构建。
此外，为实现上述目的本公开还提供了一种滤波器，所述滤波器包括如上述的谐振器。该谐振器的具体结构参照上述实施例，由于滤波器采用了上述所有实施例的全部技术方案，因此至少具有上述实施例的技术方案所带来的所有有益效果，在此不再一一赘述。
以上仅为本公开的优选实施例，并非因此限制本公开的专利范围，凡是利用本公开说明书及附图内容所作的等效结构或等效流程变换，或直接或间接运用在其他相关的技术领域，均同理包括在本公开的专利保护范围内。
显然，所描述的实施例仅仅是本公开的一部分实施例，而不是全部的实施例。基于本公开中的实施例，本领域普通技术人员在没有作出创造性劳动前提下所获得的所有其他实施例，都属于本公开保护的范围。
需要说明，本公开实施例中所有方向性指示(诸如上、下、左、右、前、后……)仅用于解释在某一特定姿态(如附图所示)下各部件之间的相对位置关系、运动情况等，如果该特定姿态发生改变时，则该方向性指示也相应地随之改变。
另外，在本公开中涉及“第一”、“第二”等的描述仅用于描述目的，而不能理解为指示或暗示其相对重要性或者隐含指明所指示的技术特征的数量。由此，限定有“第一”、“第二”的特征可以明示或者隐含地包括至少一个该特征。另外，各个实施例之间的技术方案可以相互结合，但是必须是以本领域普通技术人员能够实现为基础，当技术方案的结合出现相互矛盾或无法实现时应当人认为这种技术方案的结合不存在，也不在本公开要求的保护范围之内。

Claims (17)

  1. 一种叉指换能结构，所述叉指换能结构包括：平行设置的第一汇流排和第二汇流排，所述第一汇流排上设置有多个第一电极、所述第二汇流排上设置有多个第二电极，所述多个第一电极和所述多个第二电极相对间隔设置在所述第一汇流排和第二汇流排之间的中间区域；
    所述中间区域包含叉指区和不属于所述叉指区的单极区，所述叉指区为所述多个第一电极远离所述第一汇流排的端部边缘和所述多个第二电极远离所述第二汇流排的端部边缘之间形成的区域；
    单极区中各第一电极之间和各第二电极之间通过多个金属条连接；
    在所述叉指区内，各第一电极的电极端以及与所述第一电极相邻的第二电极的横向对应位置处设置金属加厚层；
    各第二电极的电极端以及与所述第二电极相邻的第一电极的横向对应位置处设置金属加厚层。
  2. 如权利要求1所述叉指换能结构，其中，所述单极区包括第一单极区和第二单极区，在所述第一单极区内各相邻第一电极之间通过多个金属条连接，在所述第二单极区内各相邻第二电极之间通过多个金属条连接。
  3. 如权利要求2所述叉指换能结构，其中，所述各相邻第一电极之间和/或各相邻第二电极之间设置的金属条数目相同。
  4. 如权利要求3所述叉指换能结构，其中，所述金属条为平行设置的矩形状金属条，或倾斜预设角度设置的矩形状金属条。
  5. 如权利要求4所述叉指换能结构，其中，在切斜预设角度设置的矩形状金属条中，所述第一电极和/或所述第二电极两侧的金属条与对应的所述第一电极和/或第二电极上相同的位置连接。
  6. 如权利要求3所述叉指换能结构，其中，所述金属条为梯形状金属条时，第一电极两侧或第二电极两侧连接的金属条的下底边指向上底边的方向相同或相反。
  7. 如权利要求2所述叉指换能结构，其中，所述第一电极和/或所述第二电极两侧的金属条间隔相同距离交错设置在对应的所述第一电极两侧和/或第二电极两侧。
  8. 如权利要求1所述叉指换能结构，其中，所述第一电极之间或所述第二电极之间通过多个金属条贯穿连接；其中各金属条均贯穿各第一电极或各第二电极。
  9. 如权利要求1所述叉指换能结构，其中，所述金属加厚层设置在所述第一电极和所述第二电极的上表面或下表面。
  10. 如权利要求1所述叉指换能结构，其中，相邻的各第一电极之间的电极间隙和相邻的各第二电极之间的电极间隙之间设有假指条，所述假指条与第一电极或第二电极对应设置。
  11. 如权利要求10所述叉指换能结构，其中，所述假指条与所述第一汇流排或所述第二汇流排连接，所述假指条与电极之间设置的所述多个金属条连接。
  12. 一种谐振器，所述谐振器包括：硅衬底和以此设置在所述硅衬底上的能量陷阱层、二氧化硅层、压电单晶层、权利要求1-11任一项所述的叉指换能结构以及设置在所述叉指换能结构上的钝化层。
  13. 一种基于权利要求12所述谐振器的谐振器制作方法，所述谐振器制作方法包括：
    利用高阻硅构建谐振器衬底；
    利用多晶硅在所述谐振器衬底上构建能量陷阱层；
    在所述能量陷阱层上构建低声速的二氧化硅层；
    通过键合方式在所述二氧化硅层上构建压电单晶层；
    在所述压电单晶层上设置叉指换能结构，所述叉指换能结构的各第一电极之间和各第二电极之间通过多个金属条连接；
    在各第一电极的电极端以及与所述第一电极相邻的第二电极的横向对应位置处设置金属加厚层；
    在各第二电极的电极端以及与所述第二电极相邻的第一电极的横向对应位置处设置金属加厚层；
    在所述叉指换能结构上设置钝化层。
  14. 如权利要求13所述的谐振器制作方法，其中，所述在所述能量陷阱层上构建低声速的二氧化硅层的步骤包括：
    通过气相沉积或热氧化方式在所述能量陷阱层上构建初始二氧化硅层；
    对所述初始二氧化硅层进行机械平坦化处理获得低声速的二氧化硅层。
  15. 如权利要求14所述的谐振器制作方法，其中，所述在所述压电单晶层上设置叉指换能结构，所述叉指换能结构的各第一电极之间和各第二电极之间通过多个金属条连接的步骤包括：
    在所述压电单晶层上根据预设位置关系设置第一汇流排和第二汇流排；
    在所述第一汇流排和所述第二汇流排之间依次间隔设置多个第一电极和第二电极；
    分别在各第一电极之间和各第二电极之间设置多个金属条。
  16. 如权利要求13所述的谐振器制作方法，其中，所述在所述压电单晶层上设置叉指换能结构的步骤还包括：
    在所述压电单晶层上设置金属加厚层；
    根据所述金属加厚层的位置信息设置第一电极和第二电极；
    根据所述第一电极和所述第二电极设置第一汇流排和第二汇流排；
    分别在各第一电极之间和各第二电极之间设置多个金属条。
  17. 一种滤波器，所述滤波器包括权利要求12所述的谐振器。
PCT/CN2022/116769 2022-01-28 2022-09-02 叉指换能结构、谐振器、谐振器制作方法及滤波器 WO2023142483A1 (zh)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117559952A (zh) * 2023-12-29 2024-02-13 深圳新声半导体有限公司 一种顶层设置抑制杂波单元的tc-saw谐振结构

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114567283B (zh) * 2022-01-28 2023-04-11 江苏卓胜微电子股份有限公司 叉指换能结构、谐振器、谐振器制作方法及滤波器
CN115603694B (zh) * 2022-12-14 2023-04-07 深圳新声半导体有限公司 Tc-saw器件、用于制作tc-saw器件的方法
CN116566349B (zh) * 2023-04-17 2023-11-17 无锡市好达电子股份有限公司 一种基于活塞模式的声表面波装置及制备方法
CN117318662B (zh) * 2023-11-13 2024-07-12 深圳新声半导体有限公司 声表面波谐振器、mems设备

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003218665A (ja) * 2002-01-25 2003-07-31 Kyocera Corp 弾性表面波フィルタ
CN106464229A (zh) * 2014-05-26 2017-02-22 株式会社村田制作所 弹性波装置
CN107112975A (zh) * 2014-11-28 2017-08-29 株式会社村田制作所 弹性波装置
CN110800212A (zh) * 2017-06-26 2020-02-14 株式会社村田制作所 弹性波装置以及复合滤波器装置
CN113098432A (zh) * 2021-04-08 2021-07-09 江苏卓胜微电子股份有限公司 一种声表面波谐振器和射频滤波器
CN113169719A (zh) * 2018-12-12 2021-07-23 Rf360欧洲有限责任公司 横向间隙模式激发受到抑制且横向模式减少的电声谐振器
CN113872556A (zh) * 2021-09-27 2021-12-31 江苏卓胜微电子股份有限公司 一种声表面波谐振器和射频滤波器
CN114567283A (zh) * 2022-01-28 2022-05-31 江苏卓胜微电子股份有限公司 叉指换能结构、谐振器、谐振器制作方法及滤波器

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH05110374A (ja) * 1991-10-14 1993-04-30 Nec Corp 弾性表面波フイルタ
US8294331B2 (en) * 2009-09-22 2012-10-23 Triquint Semiconductor, Inc. Acoustic wave guide device and method for minimizing trimming effects and piston mode instabilities
WO2014192755A1 (ja) * 2013-05-29 2014-12-04 株式会社村田製作所 弾性波フィルタ装置
JPWO2018131360A1 (ja) * 2017-01-10 2019-11-07 株式会社村田製作所 弾性波装置
JP6766961B2 (ja) * 2017-06-06 2020-10-14 株式会社村田製作所 弾性波フィルタ装置、マルチプレクサ及び複合フィルタ装置
SG10201911416RA (en) * 2018-12-03 2020-07-29 Skyworks Solutions Inc Acoustic Wave Device With Transverse Spurious Mode Suppression
US20200389151A1 (en) * 2019-06-07 2020-12-10 Skyworks Solutions, Inc. Acoustic wave resonator with patterned conductive layer for transverse mode suppression
CN112953439A (zh) * 2021-04-08 2021-06-11 江苏卓胜微电子股份有限公司 一种声表面波谐振器和射频滤波器

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003218665A (ja) * 2002-01-25 2003-07-31 Kyocera Corp 弾性表面波フィルタ
CN106464229A (zh) * 2014-05-26 2017-02-22 株式会社村田制作所 弹性波装置
CN107112975A (zh) * 2014-11-28 2017-08-29 株式会社村田制作所 弹性波装置
CN110800212A (zh) * 2017-06-26 2020-02-14 株式会社村田制作所 弹性波装置以及复合滤波器装置
CN113169719A (zh) * 2018-12-12 2021-07-23 Rf360欧洲有限责任公司 横向间隙模式激发受到抑制且横向模式减少的电声谐振器
CN113098432A (zh) * 2021-04-08 2021-07-09 江苏卓胜微电子股份有限公司 一种声表面波谐振器和射频滤波器
CN113872556A (zh) * 2021-09-27 2021-12-31 江苏卓胜微电子股份有限公司 一种声表面波谐振器和射频滤波器
CN114567283A (zh) * 2022-01-28 2022-05-31 江苏卓胜微电子股份有限公司 叉指换能结构、谐振器、谐振器制作方法及滤波器

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117559952A (zh) * 2023-12-29 2024-02-13 深圳新声半导体有限公司 一种顶层设置抑制杂波单元的tc-saw谐振结构

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