WO2022100468A1 - 薄膜表声波谐振器及其制造方法 - Google Patents

薄膜表声波谐振器及其制造方法 Download PDF

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Publication number
WO2022100468A1
WO2022100468A1 PCT/CN2021/127857 CN2021127857W WO2022100468A1 WO 2022100468 A1 WO2022100468 A1 WO 2022100468A1 CN 2021127857 W CN2021127857 W CN 2021127857W WO 2022100468 A1 WO2022100468 A1 WO 2022100468A1
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WIPO (PCT)
Prior art keywords
electrode
interdigital
connection line
interdigitated
sub
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PCT/CN2021/127857
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English (en)
French (fr)
Inventor
黄河
罗海龙
李伟
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中芯集成电路（宁波）有限公司上海分公司
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Publication of WO2022100468A1 publication Critical patent/WO2022100468A1/zh

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    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H3/00—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators
    • H03H3/007—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators for the manufacture of electromechanical resonators or networks
    • H03H3/02—Apparatus or processes specially adapted for the manufacture of impedance networks, resonating circuits, resonators for the manufacture of electromechanical resonators or networks for the manufacture of piezoelectric or electrostrictive resonators or networks
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
    • H03H9/02—Details

Definitions

  • the invention relates to the field of semiconductor device manufacturing, in particular to a thin-film surface acoustic wave resonator and a manufacturing method thereof.
  • SAW devices surface acoustic wave devices
  • SAW devices surface acoustic wave devices
  • SAW devices are circuit elements that convert electrical signals into surface waves and perform signal processing, and are widely used as filters, resonators, and the like.
  • the surface acoustic wave resonator is made of two interdigital transducers on the polished surface of the substrate material with piezoelectric properties, which are respectively used as a transmitting transducer and a receiving transducer.
  • the transmitting transducer converts the RF signal into a surface acoustic wave, which propagates on the surface of the substrate.
  • the receiving transducer converts the acoustic signal into an electrical signal for output.
  • the filtering process is from electricity to sound and from sound to electricity. realized in piezoelectric conversion.
  • the ends of the interdigitated electrodes are electrically connected by traditional metal leads, which easily disturbs the surface acoustic waves at the ends of the interdigitated electrodes, so that the quality factor (Q) cannot be further improved, and the yield low, so it cannot meet the needs of high-performance RF systems.
  • the purpose of the present invention is to provide a thin-film surface acoustic wave resonator and a manufacturing method thereof, which can improve the quality factor of the thin-film surface acoustic wave resonator, thereby improving the device performance.
  • the present invention provides a thin-film surface acoustic wave resonator, comprising: a first interdigital electrode with a plurality of first interdigital fingers, a second interdigitated electrode with a plurality of second interdigitated fingers, and the first interdigitated electrode has a plurality of second interdigitated fingers.
  • the finger and the second interdigital finger are arranged at intervals; the first connection line is located at at least one end of the first interdigital finger and is electrically connected with the first interdigital finger; the second connection line is located at at least one end of the second interdigital finger and is connected with the second interdigital
  • the interdigital connection is electrically connected; there is a first gap between the first connection line and the first interdigital finger, and the first connection line and the first interdigital finger are connected by a first interconnection electrode spanning the first gap; and/or, a second connection A second gap is formed between the wire and the second interdigital, and the second connection wire and the second interdigital are connected by a second interconnection electrode spanning the second gap.
  • the invention also provides a method for manufacturing a thin-film surface acoustic wave resonator, comprising: providing a piezoelectric layer; forming a first interdigital electrode with a plurality of first interdigital fingers and a plurality of second interdigital fingers on the piezoelectric layer
  • the second interdigital electrode, the first interdigital and the second interdigital are arranged at intervals; a first connection line is formed, the first connection line is formed at least at one end of the first interdigital finger, and there is a first interdigital a gap; and/or, forming a second connecting line, the second connecting line is formed at least at one end of the second interdigital finger, and has a second gap between the second interdigitating finger; forming a first interconnection electrode, the first The interconnection electrode spans the first gap and electrically connects the first interdigitated finger and the first connection line; and forms a second interconnection electrode that spans the second gap and electrically connects the second interdigitated finger and the second connection
  • the beneficial effect of the thin-film surface acoustic wave resonator of the present invention is that a first connection line is formed at at least one end of the first interdigital, and a first gap is formed between the first connection line and the first interdigital, so as to connect the first interdigital It is spaced apart from the first connection line, and then the spaced first interdigitated fingers and the first connection line are electrically connected through the first interconnection electrode.
  • first interdigital and the first connecting line form an impedance mismatch area at the first gap, thereby effectively suppressing the leakage of clutter, and then The Q value of the resonator is improved; in the same way, a second connection line is formed at at least one end of the second interdigit, and a second gap is formed between the second connection line and the second interdigit, so as to connect the second interdigit to the second interdigit
  • the connecting wires are spaced apart, and the second interdigitated fingers and the second connecting wires are electrically connected through the second interconnection electrodes. Compared with the traditional structure, the vibration resistance of the interdigitated fingers by the metal structure other than the interdigitated fingers can be reduced.
  • the second interdigital finger and the second connecting line form an impedance mismatch area at the second gap, thereby effectively suppressing the leakage of clutter, thereby improving the resonator. the Q value.
  • the disconnected first interdigital interdigital is electrically connected to the first connection line, so as to facilitate the electrical connection between the first interdigitated finger and the outside.
  • the second interdigital fingers are electrically connected to the second connecting wires, so that the second interdigitating fingers are electrically connected to the outside; in addition, the arched bridge structure can completely expose the ends of the corresponding interdigitating fingers and the connecting wires to the gas in the first gap Therefore, it is better to avoid the vibration of the connecting wire to the end of the fork, and avoid the disturbance of the surface acoustic wave at the end of the fork.
  • the first sub-arch bridge includes at least one
  • a support structure needs to be provided under the connection part between the adjacent sub-arch bridges to form support for the first arch bridge structure and avoid the structure caused by the excessive first gap.
  • the Q value of the resonator is improved
  • a support structure needs to be provided under the connection part between adjacent sub-arch bridges to avoid excessive second gap due to As a result, the structural strength of the second arch bridge structure is poor, thereby increasing the Q value of the resonator.
  • the impedances of the first interconnection electrode and the second interconnection electrode are lower than the impedances of the first interdigital and the second interdigital respectively, so that the impedances of the first interdigital and the second interdigital can be reduced, so that the first interdigital
  • the finger electrodes and the second interdigital electrodes have good electrical conductivity and improve the electrical conductivity.
  • the interdigital transducer adopts metal material with lower resistivity and better thermal conductivity, which can reduce impedance and enhance thermal conductivity.
  • both ends of the first interdigital finger and/or the second interdigitated finger are provided with connection wires, and both ends of the first interdigitated finger and/or the second interdigitated finger are powered by the connection wires, so as to improve the power supply efficiency.
  • the beneficial effects of the manufacturing method of the thin-film surface acoustic wave resonator of the present invention are: forming the first interdigital fingers and the first connecting line, and forming a first gap between the first interdigitating finger and the first connecting line, so as to connect the first interdigitating
  • the ends of the fingers and the ends of the first connection lines are spaced apart, and then a first interconnection electrode is formed to connect the spaced first interdigitated fingers and the ends of the first connection lines, so as to connect the first interdigitated fingers at the first gap.
  • the ends of the interdigitated fingers and the end of the first connecting wire are exposed in the first gap, so that it is convenient to suppress the clutter generated by the first connecting wire, thereby preventing it from disturbing the surface acoustic wave at the end of the first interdigitated finger; similarly, forming a second interdigitated finger and a second connection line, and forming a second gap between the second interdigitated finger and the second connection line to space the end of the second interdigitated finger from the end of the second connection line, and then forming a second gap between the second interdigitated finger and the second connection line
  • the second interconnection electrode is formed to connect the spaced second interdigital fingers and the ends of the second connection lines, thereby preventing the clutter generated by the second connection lines from disturbing the surface acoustic waves at the ends of the second interdigitated fingers.
  • the interdigitated electrodes can be formed simultaneously with the connection lines, or can be formed before or after the connection lines are formed.
  • the process can be saved. steps to improve efficiency.
  • a support structure can be formed in the corresponding gap to form support for the corresponding arch bridge structure and improve the structural strength of the resonator.
  • the support structure is connected to the interdigital electrode, When the lines are formed synchronously, process steps can be saved and efficiency can be improved.
  • FIG. 1 shows a schematic structural diagram of a thin-film surface acoustic wave resonator provided in Embodiment 1 of the present invention
  • Fig. 2 shows a cross-sectional view of the thin-film surface acoustic wave resonator along A-A and B-B in Embodiment 1 of the present invention
  • Fig. 3 shows Figure 4 shows a schematic structural diagram of a film surface acoustic wave resonator provided in Embodiment 3 of the present invention
  • Figure 5 shows the A schematic structural diagram of another thin-film surface acoustic wave resonator provided in Embodiment 3 of the present invention
  • FIGS. 6 to 15 show structural schematic diagrams corresponding to different steps of the manufacturing method of the thin-film surface acoustic wave resonator in Embodiment 4 of the present invention.
  • First interdigital electrode 11. First interdigital electrode; 2. Second interdigital electrode; 21. Second interdigital electrode; 3. First connecting line; 4. Second connecting line; 5 7, the first gap; 6, the second gap; 7, the first interconnection electrode; 71, the first arch bridge structure; 72, the first gap; 8, the second interconnect electrode; 81, the second arch bridge structure ; 82, the second void; 91, the substrate; 92, the piezoelectric layer; 93, the support structure; 94, the isolation layer; 95, the sacrificial layer; 96, the first protrusion; 97, the second protrusion; 98, the first Pad; 99, the second pad.
  • Embodiment 1 provides a film surface acoustic wave resonator
  • FIG. 1 is a schematic cross-sectional view of a film surface acoustic wave resonator provided in Embodiment 1 of the present invention. Please refer to FIG. 1 and FIG. 2.
  • the film surface acoustic wave resonator includes: A first interdigital electrode 1 with a plurality of first interdigitated fingers 11, a second interdigitated electrode 2 with a plurality of second interdigitated fingers 21, the first interdigitated fingers 11 and the second interdigitated fingers 21 are arranged at intervals; the first connection line 3, at least located at one end of the first interdigitated fingers 11, and electrically connected to the first interdigitated fingers 11; the second connection line 4, located at least at one end of the second interdigitated fingers 21, and electrically connected to the second interdigitated fingers 21; There is a first gap 5 between the connection line 3 and the first interdigital finger 11 , and the first connection line 3 and the first interdigital finger 11 are connected by the first interconnection electrode 7 spanning the first gap 5 ; and/or, the second connection There is a second gap 6 between the wire 4 and the second interdigital fingers 21 , and the second connection wire 4 and the second interdigital finger 21 are connected by a second interconnection electrode 8 spanning the second gap 6 .
  • the first connection lines 3 are respectively formed at both ends of the first interdigitated fingers 11
  • the second connection lines 4 are respectively formed at both ends of the second interdigitated fingers 21 , so that the first connection lines 3 are connected to the first fork.
  • the wires are spaced apart from the corresponding interdigital fingers, thereby reducing the vibration obstruction of the interdigitated fingers by the metal structure other than the interdigitating fingers, and at the same time preventing the clutter generated by the connecting wire from disturbing the surface acoustic waves at the ends of the interdigitating fingers during electrical connection; the corresponding connecting wire
  • the impedance mismatch area is formed at the corresponding gap with the interdigitated electrode, and the connection line and the interdigitated electrode are connected by the interconnection electrode, which can effectively suppress the leakage of clutter.
  • the two ends of the corresponding interdigitated fingers are in a balanced state, thereby improving the stability of the device structure.
  • the interconnection electrodes, the gaps, the connecting lines, and the interdigital fingers correspond to each other, that is, the first interconnection electrode corresponds to the first gap 5, the first connection line 3, and the first interdigital fingers 11; the second interconnection electrode corresponds to the The second gap 6 , the second connection line 4 , and the second interdigitated fingers 21 correspond to each other.
  • the gaps between the interdigitated fingers can make the two ends of the first interdigitated electrode 1 and the second interdigitated electrode 2 in a better balance state, thereby improving the stability of the device structure.
  • the first connecting wires 3 on the same side are positioned inside the second connecting wires 4
  • the first connecting wires 3 on the other same side are positioned outside the second connecting wires 4 .
  • the materials of the first connection line 3 and the second connection line 4 may refer to the materials of the first interdigitated electrode 1 and the second interdigitated electrode 2 , for details, please refer to the following.
  • the materials of the first connection wire 3 and the second connection wire 4 may be conductive materials, such as molybdenum, aluminum, copper, tungsten, tantalum, platinum, ruthenium, rhodium, iridium, chromium, titanium, gold, osmium A combination of one or more of , rhenium or palladium.
  • the first connection line 3 faces the first interconnection electrode 7 is flush with the side of the first interdigitated finger 11 facing the first interconnection electrode 7; and/or, the side of the second connection line 4 facing the second interconnection electrode 8 and the second interdigitated finger 21 facing the second interconnection One side of the electrode 8 is flush.
  • the first interconnection electrode 7 spans the first gap 5 to connect the first interdigitated fingers 11 and the first connection wire 3, and the disconnected first interdigitated finger 11 and the first connection wire 3 can be electrically connected, and the second interconnection electrode 8
  • the disconnected second interconnection electrodes 8 may be electrically connected across the second gap 6 to connect the second interdigitated fingers 21 and the second connection line 4 .
  • the impedance of the first interconnection electrode 7 is lower than the impedance of the first interdigital electrode 1
  • the impedance of the second interconnection electrode 8 is lower than the impedance of the second interdigital electrode 2, so that the When the corresponding connecting wire and the interdigital electrode are electrically connected, the impedance of the corresponding interdigital electrode is reduced, so that the first interdigital electrode 1 and the second interdigital electrode 2 have better conductivity, and the conductivity is improved.
  • the materials of the first interconnection electrode 7 and the second interconnection electrode 8 are metal materials, and the metal materials include one or more of gold, silver, tungsten, platinum, aluminum, copper, titanium, tin, and nickel.
  • the number of the first interconnection electrodes 7 is at least one.
  • the first interconnection electrode 7 covers the first interdigitated finger 11 and extends to both ends of the first interdigitated finger 11 , and spans the first gap 5 at both ends thereof to extend to the first interdigital
  • the first connection line 3 at both ends of the first interdigitated finger 11 is electrically connected to the first interdigitated finger 11; when the number of the first interconnection electrodes 7 is at least two, the first interconnection electrode 7 are respectively arranged at both ends of the first interdigitated fingers 11 to connect the first connecting lines 3 at both ends of the first interdigitated fingers 11 to the ends of the first interdigitated fingers 11 respectively.
  • the number of the second interconnection electrodes 8 can be set with reference to the first interconnection electrodes 7 , which will not be repeated here.
  • the number of the first interconnection electrode 7 and the second interconnection electrode 8 includes at least two, and they are respectively disposed at both ends of the corresponding interdigital fingers, so as to connect the ends of the corresponding interdigital fingers and the corresponding interdigital fingers respectively. Corresponding connecting wire at this end.
  • the first interconnection electrode 7 includes a first arched bridge structure 71 protruding away from the first gap 5 .
  • the inner surface of the first arched bridge structure 71 surrounds a first gap 72 , and the first gap 72 is connected to the first gap 72 .
  • the first gap 3 is opposite to each other; and/or, the second interconnection electrode 8 includes a second arched bridge structure 81 protruding away from the second gap 6 , the inner surface of the second arched bridge structure 81 encloses a second gap 82 , and the first The two gaps 82 are opposite to the second gap 6.
  • the ends of the corresponding interdigital fingers are fully exposed in the gap, so that the connection lines and the corresponding interdigital fingers can be better avoided.
  • the surface acoustic wave at the end of the electric connection is disturbed, and the leakage of the acoustic wave can also be effectively suppressed.
  • the first arch bridge structure 71 includes at least one sub-arch bridge, and a support structure 93 is provided below the connection between adjacent sub-arch bridges; and/or, the second arch bridge structure 81 includes at least one sub-arch bridge, and the adjacent sub-arch bridges are A support structure 93 is provided below the connection part between the arch bridges.
  • the first gap 72 is opposite to the first gap 5, that is, the projection of the first gap 5 on the plane where the surface of the first connecting line 3 is located is within the projection range of the first gap 72 on the plane where the surface of the first connecting line 3 is located. , or the projection of the first gap 5 on the plane where the surface of the first connecting line 3 is located partially overlaps the projection of the first gap 72 on the plane where the surface of the first connecting line 3 is located.
  • the projection of the first gap 5 on the plane where the surface of the first connecting line 3 is located is within the projection range of the first gap 72 on the plane where the surface of the first connecting line 3 is located, the effect of suppressing sound wave leakage is better, and the leaked clutter can be effectively avoided. Perturbation to the end of the first interdigital 11.
  • the second gap 82 and the second gap 6 can be set relative to each other with reference to the first gap 72 and the first gap 5 , which will not be repeated here.
  • the support structure 93 is disposed in the corresponding gap, and the support structure 93 can divide the gap into at least two mutually isolated sub-gap, or the support structure 93 can divide the gap into at least two connected sub-gap. Since the supporting structure 93 needs to support the interconnecting electrodes when the corresponding interconnecting electrodes cross the gap, its structure is not specifically limited.
  • the adjacent sub-gap isolated by the supporting structure 93 may be partially connected or completely isolated. A gap is formed, and the gap and the sub-gap are opposite one by one.
  • the support structure 93 can be made of the same material as the first connection line 3 and the second connection line 4, or a dielectric material, including but not limited to silicon oxide, silicon nitride, silicon oxynitride, silicon carbonitride and other materials. a kind of.
  • the interconnection electrode connected between the connection line located on the outer side and the corresponding interdigital finger includes the first A sub-arch bridge and a second sub-arch bridge, a support structure 93 is provided below the adjacent parts of the first sub-arch bridge and the second sub-arch bridge, and the second sub-arch bridge is located on the outside and spans the inner support structure 93 to connect with the connecting line on the outside.
  • the first interconnection electrode 7 connecting the first connection line 3 located on the outer side and the first interdigital finger 11 includes the first sub-arch bridge and
  • a support structure 93 is provided below the adjacent parts of the first sub-arch bridge and the second sub-arch bridge.
  • the arch bridge is located on the outside and spans the support structure 93 on the inside to connect with the connecting line on the outside
  • the second interconnection electrode 8 connecting the second connecting line 4 on the inside and the second interdigital 21 includes a third sub-arch bridge, the third sub-arch bridge
  • the second interdigitated fingers 21 on the inner side are connected with the second connecting line 4 on the outer side.
  • the two ends of the first interdigitated fingers 11 are electrically connected to the first connection wires 3 through the first interconnection electrodes 7 respectively, and the two ends of the second interdigitated fingers 21 are respectively connected to the second interconnection electrodes 8 through the second interconnection electrodes 8 .
  • the connecting wire 4 is electrically connected.
  • the first connection wires 7 disposed at both ends of the first interdigital fingers 11 are connected to the same first pad 98 , so as to input signals or Signals are output from both ends of the first interdigital fingers 11 respectively, thereby improving the power supply efficiency
  • the second connection wires 8 arranged at both ends of the second interdigital fingers 21 are connected to the same second pad 99, so as to facilitate the connection between the two second interdigitated fingers 21.
  • Line 4 respectively inputs signals to the two ends of the second interdigitated fingers 21 or outputs signals from both ends of the second interdigitated fingers 21 respectively, thereby improving the efficiency of signal input or output.
  • the second interdigital electrode 2 is used as a signal output terminal.
  • the first interdigital electrode 1 and the second interdigital electrode 2 are respectively used as The signal input terminal and the signal output terminal are in the process of dynamic change.
  • one end of the first interdigitated finger 11 is electrically connected to one end of the first connection wire 3 through the first interconnection electrode 7 , and the other end is pseudo-interconnected with the first connection wire 3 , that is, the first interdigitated finger 11
  • the first connection line 3 at one end is electrically connected to the external first pad 98, and does not supply power to the first connection line 3 at the other end of the first interdigitated finger 11.
  • the second interdigitated finger 21 is connected to the second interconnection electrode 8, the second For the connection structure of the connection line 4 and the second pad 99 , refer to the connection structure of the first interdigital finger 11 and the first interconnection electrode 7 , the first connection line 3 , and the first pad 98 , which will not be repeated here.
  • one end of the first interdigitated finger 11 is electrically connected to one end of the first connecting wire 3 through the first interconnection electrode 7 , and the other end is electrically connected to the first connecting wire 3 .
  • the electrical connection of the second connection wires 4 located at both ends of the second interdigitated fingers 21 may refer to the above-mentioned electrical connection settings of the first connection wires 3 at both ends of the first interdigitated fingers 11 , which will not be repeated here.
  • the first interdigital electrode 1 and the second interdigital electrode 2 can use any suitable conductive material or semiconductor material known to those skilled in the art, wherein the conductive material can be a metal material with conductive properties, for example, made of Molybdenum (Mo), Aluminum (Al), Copper (Cu), Tungsten (W), Tantalum (Ta), Platinum (Pt), Ruthenium (Ru), Rhodium (Rh), Iridium (Ir), Chromium (Cr), Titanium (Ti), gold (Au), osmium (Os), rhenium (Re), palladium (Pd) and other metals made of one or a stack formed of the above metals, semiconductor materials such as Si, Ge, SiGe, SiC, SiGeC, etc.
  • the materials of the first interdigitated fingers 11 and the second interdigitated fingers 21 may be conductive materials with low resistance, such as one or more of gold, silver, tungsten, platinum, aluminum, and copper.
  • the interdigitated electrodes and the connecting wires are both disposed on the piezoelectric layer 92, and the piezoelectric layer 92 can be made of aluminum nitride (AlN), zinc oxide (ZnO), lead zirconate titanate (PZT), Lithium niobate (LiNbO3), quartz (Quartz), potassium niobate (KNbO3) or lithium tantalate (LiTaO3) and other piezoelectric materials with wurtzite crystal structure and their combinations.
  • AlN aluminum nitride
  • ZnO zinc oxide
  • PZT lead zirconate titanate
  • Lithium niobate LiNbO3
  • quartz Quartz
  • KNbO3 potassium niobate
  • LiTaO3 lithium tantalate
  • the piezoelectric layer 92 may further include a rare earth metal such as at least one of scandium (Sc), erbium (Er), yttrium (Y), and lanthanum (La).
  • the piezoelectric layer 92 may further include a transition metal such as at least one of zirconium (Zr), titanium (Ti), manganese (Mn), and hafnium (Hf). kind.
  • the piezoelectric layer may be deposited using any suitable method known to those skilled in the art, such as chemical vapor deposition, physical vapor deposition, or atomic layer deposition.
  • the piezoelectric layer 92 is disposed on the substrate 91, and the piezoelectric layer 92 can be combined with the substrate 91 by means of deposition or bonding.
  • the bonding method includes: covalent bonding, adhesive bonding or fusion bonding, and the deposition method can be chemical vapor deposition or physical vapor deposition.
  • the substrate 91 and the piezoelectric layer 92 may also be bonded through a bonding layer, and the material of the bonding layer includes silicon oxide, silicon nitride, silicon oxynitride, silicon carbonitride or ethyl silicate.
  • the bonding layer can also use adhesives such as light-curing materials or heat-curing materials, such as adhesive film (Die Attach Film, DAF) or dry film (Dry Film), etc.
  • the material of the substrate 91 can be any suitable substrate known to those skilled in the art, for example, it can be at least one of the following materials: silicon (Si), germanium (Ge), silicon germanium (SiGe), carbon Silicon (SiC), Silicon Germanium Carbon (SiGeC), Indium Arsenide (InAs), Gallium Arsenide (GaAs), Indium Phosphide (InP) or other III/V compound semiconductors.
  • the substrate 91 may include an acoustic reflection area, or may not include an acoustic reflection area.
  • the acoustic reflection area may be a cavity or a Bragg reflection layer.
  • Embodiment 2 provides a thin-film surface acoustic wave resonator.
  • FIG. 3 is a schematic cross-sectional structure diagram of the thin-film surface acoustic wave resonator in Embodiment 2 of the present invention.
  • the difference between this embodiment and Embodiment 1 is that the connection in Embodiment 1 is located at The connection lines on the inner side of the same side and the interconnection electrodes of the corresponding interdigital fingers include the third sub-arch bridge, while the interconnection electrodes connecting the connection lines located on the inner side of the same side and the corresponding interdigitated fingers in Embodiment 2 include the third sub-arch bridge and the fourth sub-arch bridge.
  • the arch bridge can better reduce the vibration obstruction of the interdigital metal structure other than the interdigitated finger, and at the same time avoid disturbance to the surface acoustic wave at the end of the interdigital electrode.
  • the first interconnection electrode 7 connecting the first connection line 3 located on the outer side and the first interdigital finger 11 includes the first sub-arch bridge and the first interconnection electrode 7.
  • Two sub-arch bridges, the first sub-arch bridge and the second sub-arch bridge are provided with a support structure 93 below the adjacent parts, the first sub-arch bridge is located on the inside and spans the first interdigital fingers 11 on the inner side and is connected to the outer support structure 93, and the second sub-arch bridge is connected to the outer support structure 93.
  • the support structure 93 located on the outer side and spanning the inner side is connected with the connection line on the outer side, and the second interconnection electrode 8 connecting the second connection line 4 located on the inner side and the second interdigital finger 21 includes the third sub-arch bridge and the fourth sub-arch bridge, The second interdigital bridge 21 located on the inner side and spanning the inner side is connected with the support structure 93 on the outer side.
  • Other structural features of the thin-film surface acoustic wave resonator in this embodiment are the same as those in Embodiment 1, and will not be repeated here.
  • Embodiment 3 provides a thin-film surface acoustic wave resonator
  • FIGS. 4-5 are schematic cross-sectional structural diagrams of the thin-film surface acoustic wave resonator in Embodiment 3 of the present invention.
  • the difference between this embodiment and Embodiment 1 is that in Embodiment 1 Two ends of the first interdigital finger 11 and the second interdigitated finger 21 are respectively provided with connecting lines, while in Embodiment 3, a connecting line is provided at one end of the first interdigitated finger 11 and the second interdigitated finger 21 .
  • first interdigitated finger 11 is provided with a first connection line 3
  • second interdigitated finger 21 is provided with a second connection line 4
  • first connection line 3 and the second connection line 4 are located on the first interdigitated finger 11 .
  • the same side or different sides of the second interdigital finger 21 are located on the first interdigitated finger 11 .
  • the first connection line 3 and the second connection line 4 when the first connection line 3 and the second connection line 4 are located on the same side, the first connection line 3 may be located outside the second connection line 4 , and the specific structure of the first connection line 3 and the corresponding interconnection electrode refer to the above-mentioned Embodiment 1 Alternatively, the first connection line may be located on the inner side of the second connection line 4, and the specific structure of the first connection line and the corresponding interconnection electrode may refer to the above-mentioned Embodiment 2.
  • the first interconnection electrode 7 connecting the first connection line 3 and the first interdigitated fingers 11 includes a first sub-arch bridge and a second sub-arch bridge
  • the first interconnection electrode 7 connecting the first connection line 3 and the first interdigital finger 11 includes a third sub-arch bridge, and its specific structure refers to the above-mentioned Embodiment 1.
  • the second interconnection electrode 8 connecting the second connection line 4 and the second interdigital finger 21 includes the first sub-arch bridge and the second sub-arch bridge;
  • the interconnection electrode 8 includes the third sub-arch bridge, and its specific structure refers to the above-mentioned Embodiment 1.
  • Embodiment 4 provides a method for manufacturing a thin-film surface acoustic wave resonator, and the method for manufacturing a thin-film surface acoustic wave resonator includes: S01: providing a piezoelectric layer; S02: forming a first interdigitated layer having a plurality of first interdigitated fingers on the piezoelectric layer; an interdigitated electrode, a second interdigitated electrode with a plurality of second interdigitated fingers, the first interdigitated fingers and the second interdigitated fingers are arranged at intervals; a first connection line is formed, and the first connection line is formed at least among the first interdigitated fingers and/or, forming a second connection line, the second connection line is formed at least at one end of the second interdigital finger, and has a first interdigital gap between it and the second interdigital interdigital Two gaps; S03: form a first interconnection electrode, the first interconnection electrode spans the first gap and electrically connects the first interdigital finger and the first connection line
  • Step S0N does not represent a sequential order.
  • FIGS. 6 to 15 are schematic structural diagrams corresponding to corresponding steps of a method for manufacturing a thin-film surface acoustic wave resonator of the present embodiment, and the manufacturing method of the thin-film surface acoustic wave resonator provided by the present embodiment is described in detail with reference to FIGS. 6 to 15 .
  • a piezoelectric layer 92 is provided.
  • the thickness of the piezoelectric layer 92 is less than 0.3 ⁇ m.
  • the substrate 91 needs to be provided first, and then the thin piezoelectric layer 92 is deposited on the substrate 91 .
  • the material of the piezoelectric layer 92 is referred to as described in Embodiment 1, and details are not repeated here.
  • the piezoelectric layer 92 is a thick piezoelectric wafer with a thickness greater than 20 microns. In the later process, the step of thinning the piezoelectric wafer is further included to make the thickness meet the requirements for generating resonance.
  • a first interdigitated electrode, a second interdigitated electrode, a first connection line 3 , and a second connection line 4 are formed on the piezoelectric layer 92 .
  • the materials of the first connection line 3 and the second connection line 4 are different from those of the first interdigitated electrode and the second interdigitated electrode to form the first connection line 3
  • the method for the second connection line 4, the first interdigital electrode and the second interdigital electrode includes: forming a first conductive layer on the piezoelectric layer 92, patterning the first conductive layer to form the first interdigitated electrode, the second Interdigitated electrodes; a second conductive layer is formed on the piezoelectric layer 92 , and the second conductive layer is patterned to form the first connection line 3 and the second connection line 4 .
  • the first interdigitated electrode 1 and the second interdigitated electrode 2 may be formed first, and then the first connection line 3 and the second connection line 4 may be formed by a lift-off process.
  • the method for forming the first interdigitated electrode 1 and the second interdigitated electrode 2 includes: depositing and forming a first conductive layer on the piezoelectric layer 92; coating the surface of the first conductive layer with photoresist to form a photoresist layer; The pattern of the first interdigitated electrode 1 and the second interdigitated electrode 2 is required to define the mask pattern, and then it is exposed to transfer the mask pattern to the photoresist layer; the photoresist layer is developed; The photoresist layer is used as a mask, and the first conductive layer is etched through a dry etching process to form a first interdigitated electrode 1 and a second interdigitated electrode 2; the photoresist layer is removed.
  • an isolation layer 94 is deposited and formed to cover the first interdigitated electrode 1 , the second interdigitated electrode 2 and the first interdigitated electrode 1 ,
  • the piezoelectric layers 92 other than the second interdigital electrodes 2 are shown in FIG. 7 .
  • the isolation layer 94 is then patterned to form a first molding hole; a second conductive layer is formed to fill the first molding hole and cover the isolation layer 94 , referring to FIG. 8 .
  • the second conductive layer on the isolation layer 94 is removed, and the isolation layer is removed to form the first connection line 3 and the second connection line 4 .
  • the isolation layer 94 needs to be flattened.
  • the deposited isolation layer 94 and the second conductive layer need to be flattened to expose the first interdigitated electrode 1 and the second interdigitated electrode 2 covered by the isolation layer 94, so that the second The side of the conductive layer facing the subsequent interconnection electrodes is flush with the side of the first interdigitated electrode 1 and the second interdigitated electrode 2 facing the subsequent interconnection electrodes, that is, the first connection line 3 and the second connection line 4 formed face to face.
  • the side on which the interconnection electrodes are subsequently formed is flush with the sides of the first interdigitated electrode 1 and the second interdigitated electrode 2 that face the subsequent interconnection electrodes.
  • the first forming hole can be determined according to the required forming positions of the first connecting wire 3 and the second connecting wire 4, so that at least one end of the first interdigital finger 11 forms the first connecting wire 3; At least one end of the fingers 21 forms the second connection line 4 .
  • the formed first connection lines 3 and second connection lines 4 may be located on the same side or different sides of the interdigital electrodes.
  • the material of the isolation layer includes but is not limited to at least one of silicon dioxide, silicon nitride, aluminum oxide and aluminum nitride or thermal expansion tape; Silicon dioxide, borophosphosilicate glass, germanium, carbon, polyimide or photoresist; alternatively, the material of the isolation layer can be photoresist.
  • the first connection line 3 and the second connection line 4 may also be formed first, and then the first interdigitated electrode 1 and the second interdigitated electrode 2 may be formed by a lift-off process.
  • the method of forming the first connection line 3 and the second connection line 4 can refer to the above-mentioned method of forming the first interdigitated electrode 1 and the second interdigitated electrode 2. It should be noted that when defining the pattern pattern of the mask, the first connection Line 3 and second connecting line 4 define the mask pattern. In addition, the formation positions of the first connection line 3 and the second connection line 4 are related to the pattern, and can be determined by defining the pattern of the mask.
  • an isolation layer 94 is first deposited and formed to cover the first connection lines 3 , the second connection lines 4 and the piezoelectric layer 92 , referring to FIG. 9 .
  • the isolation layer 94 is then patterned to form a second forming hole; a second conductive layer is formed to fill the second forming hole and cover the isolation layer 94 .
  • the second conductive layer on the isolation layer is removed, and the isolation layer is removed; the second conductive layer located in the second forming hole is patterned to form the first interdigitated electrode 1 and the second interdigitated electrode 2 , see FIG. 10 .
  • the isolation layer 94 needs to be flattened; after the second conductive layer is formed, the isolation layer 94 and the second conductive layer formed by deposition need to be flattened to expose the isolated layer.
  • Flush that is, the formed first interdigitated electrode 1 and the second interdigitated electrode 2 are flush with the side of the subsequently formed interconnection electrodes and the first and second connection lines 3 and 4 facing the subsequently formed interconnection electrodes.
  • the second forming hole can be set according to the shape of the first interdigital electrode 1 and the second interdigital electrode 2 .
  • the process of patterning the first interdigital electrode 1 and the second interdigital electrode 2 can be referred to the above-mentioned, but not here. Repeat.
  • the materials of the first connecting wire 3 , the second connecting wire 4 , the first interdigital electrode 1 and the second interdigital electrode 2 are the same, then the first connecting wire 3 , The second connection line 4 , the first interdigitated electrode 1 and the second interdigitated electrode 2 can be formed simultaneously, specifically: forming a conductive layer on the piezoelectric layer 92 ; patterning the conductive layer to form the first connection line 3 , the second interdigital electrode 2 The connection line 4 , the first interdigitated electrode 1 and the second interdigitated electrode 2 .
  • the method of forming the first connection line 3 , the second connection line 4 , the first interdigital electrode 1 and the second interdigital electrode 2 reference may be made to the method for forming the first interdigitated electrode 1 and the second interdigitated electrode 2 described above. It should be noted that when defining the pattern of the mask pattern, the mask pattern needs to be defined according to the first connection line 3 , the second connection line 4 , the first interdigital electrode 1 and the second interdigital electrode 2 . It should be noted that the formation positions of the first connecting line 3 and the second connecting line 4 are related to the patterning.
  • a mask pattern can be defined so that the two ends of the first interdigital fingers 11 respectively form the first connecting line 3, Or make one end of the first interdigitated finger 11 form the first connection line 3, and similarly, by defining a mask pattern, the two ends of the second interdigitated finger 21 can respectively form the second connection line 4, or make the second interdigitated One end of 21 forms a second connection line 4, and the formed first connection line 3 and the second connection line 4 may be located on the same side or different sides of the interdigital electrodes.
  • the first interconnection electrode 7 is formed, and the second interconnection electrode 8 is formed.
  • the first interconnection electrode 7 and the second interconnection electrode 8 are formed.
  • the connecting electrode 7 and/or the second interconnecting electrode 8 includes at least one sub-arch bridge, and a support structure 93 is formed between adjacent sub-arch bridges.
  • the supporting structure 93 is made of the same material as the first interdigitated electrode 1 and the second interdigitated electrode 2 , so the first interconnection electrode 7 and the second interconnection electrode 8 are formed of the same material
  • the method includes: first, forming the support structure 93 when forming the first interdigitated electrode 1 , the second interdigitated electrode 2 and/or when forming the first connection line 3 and the second connection line 4 .
  • a sacrificial layer 95 is then formed to fill the first gap and the second gap and cover the first interdigitated electrode 1 , the second interdigitated electrode 2 , the first connection line 3 and the second connection line 4 , referring to FIG. 11 .
  • the sacrificial layer 95 is then etched to form the first protrusions 96 and the second protrusions 97 and expose the supporting structure 93, the interdigitated electrodes and the connecting lines around the corresponding protrusions.
  • the second protrusion 97 is located between the second connection line 4 and the end of the second interdigitated finger 21 , referring to FIG. 12 .
  • Corresponding interconnection electrodes are then formed to cover the corresponding protrusions and the exposed interdigitated electrodes and connecting lines or the interdigitated electrodes, connecting lines and supporting structures whose outer circumferences of the corresponding protrusions are exposed.
  • the first bump, the second bump and the sacrificial layer are removed, referring to FIG. 13 .
  • the exposed corresponding fingers may be some or all of the corresponding fingers around the corresponding protrusions, so that the formed mutual The connecting electrodes are disconnected on the corresponding interdigital fingers or continuously connected on the corresponding interdigital fingers.
  • the formed first interconnection electrode 7 includes a raised first arched bridge structure 71
  • the formed second interconnection electrode 8 includes a raised second arched bridge structure 81.
  • a second arched bridge structure is formed.
  • a gap 5 and a first gap 72 the first gap 5 is opposite to the first gap 72, the first gap 5 is located between the end of the first interdigital finger 11 and the first connecting line 3, and the first gap 72 is located in the first arch
  • the material of the sacrificial layer 95 can be phosphorous silicate glass, low temperature silicon dioxide, borophosphosilicate glass, germanium, amorphous carbon, polyimide or photoresist.
  • a corresponding removal method according to the material of the sacrificial layer 95, for example, when the material of the sacrificial layer 95 is polyimide or photoresist , using the ashing method to remove, the ashing method is specifically at a temperature of 250 degrees Celsius, oxygen chemically reacts with the sacrificial layer 95 through the air, and the generated gaseous substances are volatilized through the release holes.
  • a support structure 93 needs to be formed between the connecting line located on the outer side and the corresponding interdigitated ends, so that a mask pattern can be used to determine the support
  • the formation position of the structure 93 so as to avoid the situation of structural instability caused by the excessive gap; after the sacrificial layer 95 is formed, it needs to be flattened; when the support structure 93 is formed, the first interdigital electrodes 1, 1 and 1 are formed by patterning.
  • the illumination pattern needs to be defined according to the support structure 93 .
  • the formed support structure 93 divides the corresponding gap into a plurality of sub-spaces; the interconnection electrodes corresponding to the interdigital electrodes and the connecting lines covering the corresponding protrusions and their surrounding exposed interdigital electrodes and connecting lines include at least one sub-arch bridge corresponding to covering the corresponding protrusions and their surrounding areas.
  • the surrounding exposed interdigital electrodes, connecting wires, and interconnecting electrodes of the support structure 93 comprise at least two sub-arch bridges.
  • the supporting structure 93 is made of different materials from the first interdigitated electrode 1 , the second interdigitated electrode 2 , the first connecting wire 3 and the second connecting wire 4 , forming the first
  • the method for the interconnection electrode 7 and the second interconnection electrode 8 includes: firstly forming a sacrificial layer 95 , filling the first gap, the second gap and covering the first interdigitated electrode 1 , the second interdigitated electrode 2 and the first connection line 3 and the second connection line 4 ; the sacrificial layer 95 is etched again to form a third molding hole; the third molding hole is filled to form a support material layer, referring to FIG. 14 .
  • the sacrificial layer 95 is then etched to form a first protrusion 96, a second protrusion 97 and a support structure 93, and expose the support structure 93, interdigital electrodes and connection lines around the corresponding protrusions.
  • Corresponding interconnection electrodes are then formed to cover the corresponding protrusions and the exposed interdigitated electrodes and connecting lines or the interdigitated electrodes, connecting lines and supporting structures on the periphery of the corresponding protrusions, referring to FIG. 15 .
  • the first bump, the second bump and the sacrificial layer are removed.
  • the support structure 93 may also etch the first protrusions 96 and/or the first protrusions 96 and/or the first protrusions 96 and/or the first protrusions 96 and/or the first protrusions 96 and/or the The two protrusions 97 form the third forming hole; the supporting structure 93 is formed to fill the third forming hole.
  • the removal of the first protrusions, the second protrusions and the sacrificial layer refers to the foregoing description, and details are not repeated here.

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Abstract

本发明涉及一种薄膜表声波谐振器及其制造方法，其中，薄膜表声波谐振器包括：具有多个第一叉指的第一叉指电极、具有多个第二叉指的第二叉指电极，第一叉指与第二叉指间隔设置；第一连接线，至少位于第一叉指的其中一端，与第一叉指电连接；第二连接线，至少位于第二叉指的其中一端，与第二叉指电连接；第一连接线与第一叉指之间具有第一间隙，第一连接线与第一叉指通过跨越第一间隙的第一互连电极连接；和/或，第二连接线与第二叉指之间具有第二间隙，第二连接线与第二叉指通过跨越第二间隙的第二互连电极连接。本发明将叉指与相应连接线通过相应间隙隔开，以降低叉指之外的金属结构对叉指的振动阻碍，同时避免对叉指端部的表面声波造成扰动。

Description

薄膜表声波谐振器及其制造方法 技术领域
本发明涉及半导体器件制造领域，尤其涉及一种薄膜表声波谐振器及其制造方法。
 背景技术
自模拟射频通讯技术在上世纪90代初被开发以来，射频前端模块已经逐渐成为通讯设备的核心组件。在所有射频前端模块中，滤波器已成为增长势头最猛、发展前景最大的部件。随着无线通讯技术的高速发展，5G通讯协议日渐成熟，市场对射频滤波器的各方面性能也提出了更为严格的标准。滤波器的性能由组成滤波器的谐振器单元决定。SAW器件（表面声波器件）其体积小、插入损耗低、带外抑制大、品质因数高、工作频率高、功率容量大以及抗静电冲击能力良好等特点，成为最适合5G应用的滤波器之一。SAW器件（表面声波器件）是将电信号转换为表面波并进行信号处理的电路元件，作为滤波器、谐振器等而被广泛使用。
通常，表面声波谐振器实在具有压电特性的基片材料抛光面上制作两个叉指换能器，分别作为发射换能器和接收换能器。发射换能器将RF信号转换为声表面波，在基片表面上传播，经过一定的延迟后，接收换能器将声信号转换为电信号输出，滤波过程是在电到声和声到电的压电转换中实现。
 技术问题
但是，目前制作出的表声波谐振器，其叉指电极的端部通过传统金属引线电连，容易对叉指电极端部的表面声波造成扰动，使得品质因子（Q）无法进一步提高、成品率低，因此无法满足高性能的射频系统的需求。
 技术解决方案
本发明的目的在于提供一种薄膜表声波谐振器及其制造方法，能够提高薄膜表声波谐振器的品质因子，进而提高器件性能。
为了实现上述目的，本发明提供了一种薄膜表声波谐振器，包括：具有多个第一叉指的第一叉指电极、具有多个第二叉指的第二叉指电极，第一叉指与第二叉指间隔设置；第一连接线，至少位于第一叉指的其中一端，与第一叉指电连接；第二连接线，至少位于第二叉指的其中一端，与第二叉指电连接；第一连接线与第一叉指之间具有第一间隙，第一连接线与第一叉指通过跨越第一间隙的第一互连电极连接；和/或，第二连接线与第二叉指之间具有第二间隙，第二连接线与第二叉指通过跨越第二间隙的第二互连电极连接。
本发明还提供了一种薄膜表声波谐振器的制造方法，包括：提供压电层；在压电层上形成具有多个第一叉指的第一叉指电极、具有多个第二叉指的第二叉指电极，第一叉指和第二叉指间隔设置；形成第一连接线，第一连接线至少形成于第一叉指的其中一端，且与第一叉指之间具有第一间隙；和/或，形成第二连接线，第二连接线至少形成于第二叉指的其中一端，且与第二叉指之间具有第二间隙；形成第一互连电极，第一互连电极跨越第一间隙并电连接第一叉指和第一连接线；形成第二互连电极，第二互连电极跨越第二间隙并电连接第二叉指和第二连接线。
 有益效果
本发明的薄膜表声波谐振器的有益效果在于：在第一叉指的至少一端形成第一连接线，且第一连接线和第一叉指之间形成第一间隙，以将第一叉指和第一连接线间隔开，再通过第一互连电极将被间隔开的第一叉指和第一连接线电连，与传统结构相比，可以降低叉指之外的金属结构对叉指的振动阻碍，同时避免对第一叉指端部的表面声波造成扰动，此外，第一叉指和第一连接线在第一间隙处形成阻抗失配区，从而有效抑制杂波的泄露，进而提升谐振器的Q值；同理，在第二叉指的至少一端形成第二连接线，且第二连接线和第二叉指之间形成第二间隙，以将第二叉指和第二连接线间隔开，再通过第二互连电极将被间隔开的第二叉指和第二连接线电连，与传统结构相比，可以降低叉指之外的金属结构对叉指的振动阻碍，同时避免对第二叉指端部的表面声波造成扰动，此外，第二叉指和第二连接线在第二间隙处形成阻抗失配区，从而有效抑制杂波的泄露，进而提升谐振器的Q值。
进一步地，通过拱形桥结构，以将断开的第一叉指与第一连接线电连接，从而便于第一叉指与外部电连，同样的通过第二拱形桥结构将断开的第二叉指与第二连接线电连接，从而便于第二叉指与外部电连；另外，拱形桥结构可以使相应叉指及连接线的端部完全被暴露于第一间隙内的气体中，从而较好的避免连接线对叉指端部的振动拽，避免对叉指端部的表面声波造成扰动。进一步地，当第一子拱桥包含至少一个时，需要对相邻子拱桥之间的连接部位下方设置支撑结构，以对第一拱形桥结构形成支撑，避免由于第一间隙过大造成的结构强度较差情况，进而提高谐振器的Q值；同理，将第二子拱桥包含至少一个时，需要对相邻子拱桥之间的连接部位下方设置支撑结构，以避免由于第二间隙过大造成第二拱形桥结构的结构强度较差情况，进而提高谐振器的Q值。
进一步地，第一互连电极、第二互连电极的阻抗分别低于第一叉指、第二叉指的阻抗，可以以降低第一叉指和第二叉指的阻抗，使第一叉指电极和第二叉指电极具有较好的导电性，提高导电率。
进一步地，叉指换能器，采用电阻率更低且导热性较好的金属材料，能够减小阻抗并增强导热。
进一步地，第一叉指和/或第二叉指的两端均设有连接线，且均通过连接线向第一叉指和/或第二叉指的两端供电，以提高供电效率。
本发明的薄膜表声波谐振器的制造方法的有益效果在于：形成第一叉指和第一连接线，并在第一叉指和第一连接线之间形成第一间隙，以将第一叉指的端部和第一连接线的端部间隔开，再形成第一互连电极将间隔开的第一叉指和第一连接线的端部连接起来，以在第一间隙处将第一叉指的端部和第一连接线的端部暴露于第一间隙中，从而便于抑制第一连接线产生杂波，进而避免其对第一叉指端部的表面声波造成扰动；同理，形成第二叉指和第二连接线，并在第二叉指和第二连接线之间形成第二间隙，以将第二叉指的端部和第二连接线的端部间隔开，再形成第二互连电极将间隔开的第二叉指和第二连接线的端部连接起来，从而避免第二连接线产生的杂波对第二叉指端部的表面声波造成扰动。
进一步地，在形成相应叉指电极和相应连接线时，叉指电极可以与连接线同步形成，也可以在形成连接线之前或之后形成，当叉指电极与连接线同步形成时，可以节省工艺步骤，提高效率。
进一步地，当相应互连电极包括至少一子拱桥时，可以在相应间隙中形成支撑结构，以对相应拱形桥结构形成支撑，提高谐振器的结构强度，当支撑结构与叉指电极、连接线同步形成时，可以节省工艺步骤，提高效率。
 附图说明
为了更清楚地说明本发明实施例或现有技术中的技术方案，下面将对实施例或现有技术描述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发明的一些实施例，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获得其他的附图。
图1示出了本发明实施例1提供的一种薄膜表声波谐振器的结构示意图；图2示出了本发明实施例1中沿A-A、B-B的薄膜表声波谐振器的剖视图；图3示出了本发明实施例2提供的一种薄膜表声波谐振器的剖面结构示意图；图4示出了本发明实施例3提供的一种薄膜表声波谐振器的结构示意图；图5示出了本发明实施例3提供的另一种薄膜表声波谐振器的结构示意图；图6至图15示出了本发明实施例4的薄膜表声波谐振器的制造方法不同步骤对应的结构示意图。
附图标记说明：1、第一叉指电极；11、第一叉指；2、第二叉指电极；21、第二叉指；3、第一连接线；4、第二连接线；5、第一间隙；6、第二间隙；7、第一互连电极；71、第一拱形桥结构；72、第一空隙；8、第二互连电极；81、第二拱形桥结构；82、第二空隙；91、基板；92、压电层；93、支撑结构；94、隔离层；95、牺牲层；96、第一凸起；97、第二凸起；98、第一焊盘；99、第二焊盘。
 本发明的实施方式
以下结合附图和具体实施例对本发明的薄膜表声波谐振器及其制作方法作进一步详细说明。根据下面的说明和附图，本发明的优点和特征将更清楚，然而，需说明的是，本发明技术方案的构思可按照多种不同的形式实施，并不局限于在此阐述的特定实施例。附图均采用非常简化的形式且均使用非精准的比例，用以方便、明晰地辅助说明本发明实施例的目的。
在说明书和权利要求书中的术语“第一”“第二”等用于在类似要素之间进行区分，且未必是用于描述特定次序或时间顺序。要理解，在适当情况下，如此使用的这些术语可替换，例如可使得本文所述的本发明实施例能够以不同于本文所述的或所示的其他顺序来操作。类似的，如果本文所述的方法包括一系列步骤，且本文所呈现的这些步骤的顺序并非必须是可执行这些步骤的唯一顺序，且一些所述的步骤可被省略和/或一些本文未描述的其他步骤可被添加到该方法。若某附图中的构件与其他附图中的构件相同，虽然在所有附图中都可轻易辨认出这些构件，但为了使附图的说明更为清楚，本说明书不会将所有相同构件的标号标于每一图中。
实施例 1
实施例1提供了一种薄膜表声波谐振器，图1为本发明实施例1提供的一种薄膜表声波谐振器的剖面示意图，请参考图1和图2，该薄膜表声波谐振器包括：具有多个第一叉指11的第一叉指电极1、具有多个第二叉指21的第二叉指电极2，第一叉指11与第二叉指21间隔设置；第一连接线3，至少位于第一叉指11的其中一端，与第一叉指11电连接；第二连接线4，至少位于第二叉指21的其中一端，与第二叉指21电连接；第一连接线3与第一叉指11之间具有第一间隙5，第一连接线3与第一叉指11通过跨越第一间隙5的第一互连电极7连接；和/或，第二连接线4与第二叉指21之间具有第二间隙6，第二连接线4与第二叉指21通过跨越第二间隙6的第二互连电极8连接。
在本实施例中，在第一叉指11的两端分别形成第一连接线3，在第二叉指21的两端分别形成第二连接线4，使得第一连接线3与第一叉指11端部之间具有的第一间隙5、第二连接线4与第二叉指21端部之间具有的第二间隙6，从而通过第一间隙5和第二间隙6分别将相应连接线和相应叉指间隔开，从而降低叉指之外的金属结构对叉指的振动阻碍，同时避免连接线产生的杂波在电连时对叉指端部的表面声波造成扰动；相应连接线和叉指电极在相应的间隙处形成阻抗失配区，通过互连电极连接连接线和叉指电极，可以有效抑制杂波的泄露。另外，通过在相应叉指的两端分别设置连接线，以使相应叉指的两端处于平衡状态，从而提高器件结构的稳定性。相应为互连电极、间隙、连接线、叉指相应之间相互对应，即第一互连电极与第一间隙5、第一连接线3、第一叉指11相应；第二互连电极与第二间隙6、第二连接线4、第二叉指21相应。
位于第一叉指11和第二叉指21同一侧的第一连接线3和第二连接线4，其中之一位于另一的外侧，位于内侧的连接线穿过外侧的连接线与相应的叉指之间的间隙，从而使第一叉指电极1和第二叉指电极2的两端处于较好的平衡状态，进而提高器件结构的稳固度。具体而言，当位于一同一侧的第一连接线3位于第二连接线4的内侧时，位于另一同一侧的第一连接线3位于第二连接线4的外侧。需要说明的是，第一连接线3、第二连接线4的材料可参照第一叉指电极1、第二叉指电极2的材料，具体参见下文。在其他实施例中，第一连接线3、第二连接线4的材料可采用导电材料，如钼、铝、铜、钨、钽、铂、钌、铑、铱、铬、钛、金、锇、铼或钯中的一种或多种的组合。
在本实施例中，为便于形成第一连接线3、第二连接线4、第一叉指电极1和第二叉指电极2，简化制作工艺，第一连接线3面向第一互连电极7的一面与第一叉指11面向第一互连电极7的一面齐平；和/或，第二连接线4面向第二互连电极8的一面与第二叉指21面向第二互连电极8的一面齐平。
第一互连电极7跨越第一间隙5以连接第一叉指11和第一连接线3，可以将断开的第一叉指11和第一连接线3电连接，第二互连电极8跨越第二间隙6以连接第二叉指21和第二连接线4，可以将断开的第二互连电极8跨越第二间隙6电连接。在本实施例中，第一互连电极7的阻抗低于第一叉指电极1的阻抗，第二互连电极8的阻抗低于第二叉指电极2的阻抗，从而在通过互连电极电连相应连接线和叉指电极时，降低相应叉指电极的阻抗，使第一叉指电极1和第二叉指电极2具有较好的导电性，提高导电率。第一互连电极7、第二互连电极8的材料为金属材料，金属材料包括金、银、钨、铂、铝、铜、钛、锡、镍中的一种或多种。
第一互连电极7的数量为至少一个。当第一互连电极7为整体结构时，第一互连电极7覆盖第一叉指11并向第一叉指11两端延伸，并分别跨越其两端的第一间隙5以延伸至第一连接线3上，从而将位于第一叉指11两端的第一连接线3电连至第一叉指11上；当第一互连电极7的数量为至少两个时，第一互连电极7分设于第一叉指11的两端，以分别将第一叉指11两端的第一连接线3与第一叉指11的端部相连。需要说明的是，第二互连电极8的数量可参照第一互连电极7设置，此处不再赘述。另外，在本实施例中，第一互连电极7和第二互连电极8的数量均包括至少两个，且分别设置于相应叉指的两端，以分别连接相应叉指的端部和位于该端部的相应连接线。
在本实施例中，第一互连电极7包括远离第一间隙5凸起的第一拱形桥结构71，第一拱形桥结构71内表面围成第一空隙72，第一空隙72与第一间隙3相对；和/或，第二互连电极8包括远离第二间隙6凸起的第二拱形桥结构81，第二拱形桥结构81内表面围成第二空隙82，第二空隙82与第二间隙6相对，通过在互连电极上形成相应拱形桥结构，以使相应叉指的端部被充分暴露于间隙中，从而可以较好的避免连接线与相应叉指电连时对其端部的表面声波造成扰动，还可以有效抑制声波的泄露。具体地，第一拱形桥结构71至少包括一子拱桥，相邻子拱桥之间连接部位下方设置支撑结构93；和/或，第二拱形桥结构81至少包括一子拱桥，相邻子拱桥之间连接部位下方设置支撑结构93。
需要注意的是，第一空隙72与第一间隙5相对，即第一间隙5在第一连接线3表面所在平面的投影位于第一空隙72在第一连接线3表面所在平面的投影范围内，或第一间隙5在第一连接线3表面所在平面的投影与第一空隙72在第一连接线3表面所在平面的投影部分重叠。当第一间隙5在第一连接线3表面所在平面的投影位于第一空隙72在第一连接线3表面所在平面的投影范围内时，抑制声波泄露效果较佳，且有效避免泄露的杂波对第一叉指11端部的扰动。第二空隙82与第二间隙6相对可参照第一空隙72与第一间隙5相对设置，此处不再赘述。
另外，支撑结构93设置于相应间隙内，支撑结构93可以将该间隙分隔成至少两个相互隔离的子间隙，或者，支撑结构93可以将该间隙分隔成至少两个连通的子间隙。由于支撑结构93需在相应互连电极跨越间隙时对互连电极起支撑作用，因此对其结构不作具体限定，通过支撑结构93隔离的相邻子间隙可以部分连通或完全隔离，子拱桥内表面围成空隙，空隙与子间隙一一相对。支撑结构93可以采用与第一连接线3、第二连接线4相同的材料，也可以采用介电材料，包括但不限于氧化硅、氮化硅、氮氧化硅、碳氮化硅等材料中的一种。
由于位于外侧的连接线与相应叉指之间的间隙可能较大，以影响跨越间隙的相应互连电极的稳定性，因此，位于外侧的连接线与相应的叉指连接的互连电极包括第一子拱桥和第二子拱桥，第一子拱桥和第二子拱桥相邻部位下方设支撑结构93，第二子拱桥位于外侧且横跨内侧的支撑结构93以与外侧的连接线连接。以位于同一侧的第一连接线3位于第二连接线4的外侧为例，则连接位于外侧的第一连接线3和第一叉指11的第一互连电极7包括第一子拱桥和第二子拱桥，第一子拱桥和第二子拱桥相邻部位下方设支撑结构93，第一子拱桥位于内侧且横跨内侧的第一叉指11与外侧的支撑结构93连接，第二子拱桥位于外侧且横跨内侧的支撑结构93与外侧的连接线连接，连接位于内侧的第二连接线4和第二叉指21的第二互连电极8包括第三子拱桥，第三子拱桥横跨内侧的第二叉指21与外侧的第二连接线4连接。需要说明的是，当另一同一侧的第一连接线3位于第二连接线4的内侧时，即该侧的第二连接线4位于第一连接线3的外侧时，参照上文所述的第一连接线3位于第二连接线4的外侧的设置，此处不再赘述。
在本实施例中，第一叉指11的两端分别通过第一互连电极7与第一连接线3电连接，第二叉指21的两端分别通过第二互连电极8与第二连接线4电连接。具体地，将设置于第一叉指11两端的第一连接线7连接至同一第一焊盘98上，以便于通过两第一连接线3分别向第一叉指11的两端输入信号或分别从第一叉指11的两端输出信号，从而提高供电效率，将设置于第二叉指21两端的第二连接线8连接至同一第二焊盘99上，以便于通过两第二连接线4分别向第二叉指21的两端输入信号或分别从第二叉指21的两端输出信号，从而提高信号输入或输出的效率，当第一叉指电极1作为信号输入端时，第二叉指电极2作为信号输出端，在实际使用过程中，第一叉指电极1和第二叉指电极2接入交流电后，第一叉指电极1和第二叉指电极2分别作为信号输入端和信号输出端并处于动态变化的过程。
在其他实施例中，第一叉指11的一端通过第一互连电极7与第一连接线3的一端电连接，另一端与第一连接线3伪互连，即将位于第一叉指11一端的第一连接线3与外部第一焊盘98电连，不向位于第一叉指11另一端的第一连接线3供电，第二叉指21与第二互连电极8、第二连接线4、第二焊盘99的连接结构参照第一叉指11与第一互连电极7、第一连接线3、第一焊盘98的连接结构，此处不再赘述。
在其他实施例中，第一叉指11的一端通过第一互连电极7与第一连接线3的一端电连接，另一端与第一连接线3接触电连接。
同样的，位于第二叉指21两端的第二连接线4的电连接可参照上述位于第一叉指11两端的第一连接线3的电连接设置，此处不再赘述。
一般的，第一叉指电极1和第二叉指电极2可以使用本领域技术人员任意熟知的任意合适的导电材料或半导体材料，其中，导电材料可以为具有导电性能的金属材料，例如，由钼（Mo）、铝（Al）、铜（Cu）、钨（W）、钽（Ta）、铂（Pt）、钌（Ru）、铑（Rh）、铱（Ir）、铬（Cr）、钛（Ti）、金(Au)、锇(Os)、铼(Re)、钯(Pd)等金属中一种制成或由上述金属形成的叠层制成，半导体材料例如是Si、Ge、SiGe、SiC、SiGeC等。第一叉指11和第二叉指21的材料可以为阻抗小的导电材料，比如为金、银、钨、铂、铝、铜中的一种或多种。
在本实施例中，叉指电极和连接线均设置于压电层92上，压电层92的材料可以使用氮化铝(AlN)、氧化锌(ZnO)、锆钛酸铅(PZT)、铌酸锂(LiNbO3)、石英(Quartz)、铌酸钾(KNbO3)或钽酸锂(LiTaO3)等具有纤锌矿型结晶结构的压电材料及它们的组合。当压电层92包括氮化铝(AlN)时，压电层92还可包括稀土金属，例如钪(Sc)、铒(Er)、钇(Y)和镧(La)中的至少一种。此外，当压电层92包括氮化铝(AlN)时，压电层92还可包括过渡金属，例如锆(Zr)、钛(Ti)、锰(Mn)和铪(Hf)中的至少一种。可以使用化学气相沉积、物理气相沉积或原子层沉积等本领域技术人员熟知的任何适合的方法沉积形成压电层。
压电层92设置于基板91上，压电层92可以采用沉积或键合的方式与基板91结合。键合的方式包括：共价键键合、粘结键合或熔融键合，沉积的方式可以为化学气相沉积或物理气相沉积。在其他实施例中，基板91与压电层92还可以通过键合层实现键合，键合层的材料包括氧化硅、氮化硅、氮氧化硅、碳氮化硅或硅酸乙酯。此外，键合层还可以采用光固化材料或热固化材料等黏结剂，例如粘片膜（Die Attach Film，DAF）或干膜（Dry Film）等。基板91的材质可以为本领域技术人员熟知的任意合适的底材，例如可以是以下所提到的材料中的至少一种：硅(Si)、锗(Ge)、锗硅(SiGe)、碳硅(SiC)、碳锗硅(SiGeC)、砷化铟(InAs)、砷化镓(GaAs)、磷化铟(InP)或者其它III/V化合物半导体。需要说明的是，基板91可以包括声反射区，也可以不包括声反射区，当基板91上设有声反射区时，声反射区可以为空腔或布拉格反射层。
实施例 2
实施例2提供了一种薄膜表声波谐振器，图3为本发明实施例2的薄膜表声波谐振器的剖面结构示意图，本实施例与实施例1的区别在于，实施例1中的连接位于同一侧内侧的连接线和相应叉指的互连电极包括第三子拱桥，而实施例2中连接位于同一侧内侧的连接线和相应叉指的互连电极包括第三子拱桥和第四子拱桥，可以较好的降低叉指之外的金属结构对叉指的振动阻碍，同时避免对叉指电极端部的表面声波造成扰动。具体为：
以位于同一侧的第一连接线3位于第二连接线4的外侧为例，连接位于外侧的第一连接线3和第一叉指11的第一互连电极7包括第一子拱桥和第二子拱桥，第一子拱桥和第二子拱桥相邻部位下方设支撑结构93，第一子拱桥位于内侧且横跨内侧的第一叉指11与外侧的支撑结构93连接，第二子拱桥位于外侧且横跨内侧的支撑结构93与外侧的连接线连接，连接位于内侧的第二连接线4和第二叉指21的第二互连电极8包括第三子拱桥和第四子拱桥，第三子拱桥位于内侧且横跨内侧的第二叉指21与其外侧的支撑结构93连接，第二子拱桥位于外侧且横跨其内侧的支撑结构93与外侧的第二连接线4连接。本实施例薄膜表声波谐振器的其它结构特征与实施例1相同，此处不再赘述。
实施例 3
实施例3提供了一种薄膜表声波谐振器，图4-图5为本发明实施例3的薄膜表声波谐振器的剖面结构示意图，本实施例与实施例1的区别在于，实施例1中第一叉指11、第二叉指21的两端分别设有连接线，而实施例3中在第一叉指11、第二叉指21的一端设置连接线。具体为：第一叉指11的一端设有第一连接线3，第二叉指21的一端设有第二连接线4，第一连接线3与第二连接线4位于第一叉指11、第二叉指21的同一侧或不同侧。
参照图4，当第一连接线3与第二连接线4位于同一侧时，第一连接线3可以位于第二连接线4的外侧，其与相应互连电极的具体结构参照上述实施例1；或者，第一连接线可以位于第二连接线4的内侧，其与相应互连电极的具体结构参照上述实施例2。
参照图5，当第一连接线3与第二连接线4位于不同侧时，连接第一连接线3和第一叉指11的第一互连电极7包括第一子拱桥和第二子拱桥；或者，连接第一连接线3和第一叉指11的第一互连电极7包括第三子拱桥，其具体结构参照上述实施例1。同样的，连接第二连接线4和第二叉指21的第二互连电极8包括第一子拱桥和第二子拱桥；或者，连接第二连接线4和第二叉指21的第二互连电极8包括第三子拱桥，其具体结构参照上述实施例1。
实施例 4
实施例4提供了一种薄膜表声波谐振器的制造方法，薄膜表声波谐振器的制造方法包括：S01：提供压电层；S02：在压电层上形成具有多个第一叉指的第一叉指电极、具有多个第二叉指的第二叉指电极，第一叉指和第二叉指间隔设置；形成第一连接线，第一连接线至少形成于第一叉指的其中一端，且与第一叉指之间具有第一间隙；和/或，形成第二连接线，第二连接线至少形成于第二叉指的其中一端，且与第二叉指之间具有第二间隙；S03：形成第一互连电极，第一互连电极跨越第一间隙并电连接第一叉指和第一连接线；形成第二互连电极，第二互连电极跨越第二间隙并电连接第二叉指和第二连接线。
步骤S0N不代表先后顺序。
图6至图15为本实施例的一种薄膜表声波谐振器的制造方法的相应步骤对应的结构示意图，参考图6至15详细说明本实施例提供的薄膜表声波谐振器的制造方法。
参考图6，提供压电层92。
在本实施例中，压电层92的厚度小于0.3微米，此时，在提供压电层92之前，还需先提供基板91，再在基板91上沉积形成薄压电层92。压电层92的材料参照实施例1中所述，此处不再赘述。在其他实施例中，压电层92为厚的压电晶圆，厚度大于20微米，在后期工艺中还包括对压电晶圆减薄处理的步骤，使其厚度满足产生谐振的要求。
参考图7-11，在压电层92上形成第一叉指电极、形成第二叉指电极、形成第一连接线3、形成第二连接线4。
参照图7-图10，在另一种可能的实现方式中，第一连接线3、第二连接线4和第一叉指电极、第二叉指电极的材料不同，形成第一连接线3、第二连接线4、第一叉指电极和第二叉指电极的方法包括：在压电层92上形成第一导电层，图形化第一导电层以形成第一叉指电极、第二叉指电极；在压电层92上形成第二导电层，图形化第二导电层以形成第一连接线3和第二连接线4。
具体而言，参照图7-图8，可以先形成第一叉指电极1、第二叉指电极2，再利用剥离工艺形成第一连接线3、第二连接线4。形成第一叉指电极1、第二叉指电极2的方法包括：在压电层92上沉积形成第一导电层；对第一导电层表面涂光刻胶以形成光刻胶层；根据所需第一叉指电极1和第二叉指电极2图形定义光罩图形，再对其进行曝光，以将光罩图形转移至光刻胶层上；对光刻胶层进行显影；以显影后的光刻胶层作为掩膜，通过干法刻蚀工艺刻蚀第一导电层，形成第一叉指电极1和第二叉指电极2；去除光刻胶层。
具体地，在形成第一叉指电极1、第二叉指电极2后，先沉积形成隔离层94，以覆盖第一叉指电极1、第二叉指电极2和第一叉指电极1、第二叉指电极2以外的压电层92，参照图7。再图形化隔离层94，形成第一成型孔；形成第二导电层，填充第一成型孔并覆盖隔离层94，参照图8。最后去除位于隔离层94上的第二导电层、去除隔离层，形成第一连接线3和第二连接线4。
需要说明的是，在图形化隔离层94之前，需要先对隔离层94进行平整。在形成第二导电层之后，需要对沉积形成的隔离层94和第二导电层进行平整，以暴露被隔离层94覆盖的第一叉指电极1、第二叉指电极2，从而使得第二导电层面向后续形成互连电极的一面与第一叉指电极1、第二叉指电极2面向后续形成互连电极的一面齐平，即形成的第一连接线3、第二连接线4面向后续形成互连电极的一面与第一叉指电极1、第二叉指电极2面向后续形成互连电极的一面齐平。第一成型孔可以根据第一连接线线3、第二连接线4所需的形成位置确定，以使第一叉指11的至少一端形成第一连接线3；和/或，使第二叉指21的至少一端形成第二连接线4。另外，形成的第一连接线3、第二连接线4可以位于叉指电极的同一侧或不同侧。
为了便于去除隔离层，隔离层的材质包括但不限于二氧化硅、氮化硅、氧化铝和氮化铝中或热膨胀胶带中的至少一种；或者，隔离层的材质包括磷硅玻璃、低温二氧化硅、硼磷硅玻璃、锗、碳、聚酰亚胺或光阻剂；或者，隔离层的材质可以为光刻胶。通过在形成叉指电极之后、形成连接线之前，形成隔离层，以将连接线和叉指电极隔离，从而有效避免后形成的连接线将先形成的叉指电极覆盖。
另外，参照图9-图10，也可以先形成第一连接线3、第二连接线4，再利用剥离工艺形成第一叉指电极1、第二叉指电极2。形成第一连接线3、第二连接线4的方法可参照上述形成第一叉指电极1和第二叉指电极2的方法，应当注意，在定义光罩图形图案时，需根据第一连接线3、第二连接线4定义光罩图形。另外，第一连接线3、第二连接线4的形成位置与图形化有关，可以通过定义光罩图形确定。
具体地，形成第一连接线3、第二连接线4之后，先沉积形成隔离层94，覆盖第一连接线3、第二连接线4和压电层92，参照图9。再图形化隔离层94，形成第二成型孔；形成第二导电层，填充第二成型孔并覆盖隔离层94。最后去除位于隔离层上的第二导电层、去除隔离层；图形化位于第二成型孔内的第二导电层，形成第一叉指电极1和第二叉指电极2，参照图10。
需要说明的是，在图形化隔离层94之前，需要先对隔离层94进行平整；在形成第二导电层之后，需要对沉积形成的隔离层94和第二导电层进行平整，以暴露被隔离层94覆盖的第一连接线3、第二连接线4，从而使得第二导电层面向后续形成互连电极的一面与第一连接线3、第二连接线4面向后续形成互连电极的一面齐平，即形成的第一叉指电极1、第二叉指电极2面向后续形成互连电极的一面与第一连接线3、第二连接线4面向后续形成互连电极的一面齐平。第二成型孔可以根据第一叉指电极1、第二叉指电极2的形状进行设置，图形化第一叉指电极1、第二叉指电极2的过程可参照前文所述，此处不再赘述。
继续参照图10，在一种可能的实现方式中，第一连接线3、第二连接线4、第一叉指电极1和第二叉指电极2的材料相同，则第一连接线3、第二连接线4、第一叉指电极1和第二叉指电极2可以同步形成，具体为：在压电层92上形成导电层；图形化导电层以形成第一连接线3、第二连接线4、第一叉指电极1和第二叉指电极2。形成第一连接线3、第二连接线4、第一叉指电极1和第二叉指电极2的方法可参照上述形成第一叉指电极1和第二叉指电极2的方法。应当注意，在定义光罩图形图案时，需根据第一连接线3、第二连接线4、第一叉指电极1和第二叉指电极2定义光罩图形。需要说明的是，第一连接线3、第二连接线4的形成位置与图形化有关，如可以通过定义光罩图形图案，使得第一叉指11的两端分别形成第一连接线3，或使得第一叉指11的一端形成第一连接线3，同样的，可以通过定义光罩图形图案，使得第二叉指21的两端分别形成第二连接线4，或使得第二叉指21的一端形成第二连接线4，形成的第一连接线3、第二连接线4可以位于叉指电极的同一侧或不同侧。
参考图11-图15，形成第一互连电极7，形成第二互连电极8。
具体地，在形成第一叉指电极1、第二叉指电极2、第一连接线3和第二连接线4后，形成第一互连电极7、第二互连电极8，第一互连电极7和/或第二互连电极8包括至少一子拱桥，相邻子拱桥之间形成支撑结构93。
参照图11-图13，在本实施例中，支撑结构93与第一叉指电极1、第二叉指电极2的材料相同，则形成第一互连电极7、第二互连电极8的方法包括：先在形成第一叉指电极1、第二叉指电极2和/或在形成第一连接线3、第二连接线4时，形成支撑结构93。再形成牺牲层95，填充第一间隙、第二间隙并覆盖第一叉指电极1、第二叉指电极2、第一连接线3和第二连接线4，参照图11。再刻蚀牺牲层95，形成第一凸起96和第二凸起97并暴露相应凸起四周的支撑结构93、叉指电极和连接线，第一凸起96位于第一连接线3和第一叉指11的端部之间，第二凸起97位于第二连接线4和第二叉指21的端部之间，参照图12。再形成相应的互连电极，覆盖相应凸起以及相应凸起外周被暴露的叉指电极和连接线或叉指电极、连接线和支撑结构。最后，去除第一凸起、第二凸起和牺牲层，参照图13。
应当注意，刻蚀牺牲层95形成第一凸起96和第二凸起97时，被暴露的相应叉指可以为相应凸起四周的部分相应叉指或全部相应叉指，从而使得形成的互连电极在相应叉指上断开或在相应叉指上连续相接。
形成的第一互连电极7包括凸起的第一拱形桥结构71，形成的第二互连电极8包括凸起的第二拱形桥结构81，去除第一凸起96之后，形成第一间隙5和第一空隙72，第一间隙5和第一空隙72相对，第一间隙5位于第一叉指11的端部和第一连接线3之间，第一空隙72位于第一拱形桥结构71内表面；去除第二凸起97之后，形成第二间隙6和第二空隙82，第二间隙6和第二空隙82相对，第二间隙6位于第二叉指21的端部和第二连接线4之间，第二空隙82位于第二拱形桥结构81的内表面，具体参照实施例1所述，此处不再赘述。
牺牲层95的材料可以为磷硅玻璃、低温二氧化硅、硼磷硅玻璃、锗、非晶碳、聚酰亚胺或光阻剂。另外，在去除牺牲层95时，需要先在互连电极上形成释放孔，再根据牺牲层95的材料选择相对应的去除方法，比如当牺牲层95材料为聚酰亚胺或光阻剂时，采用灰化的方法去除，灰化的方法具体为在250摄氏度的温度下，氧气通过空气与牺牲层95发生化学反应，生成气体物质通过释放孔挥发掉。
需要说明的是，当第一连接线3和第二连接线4位于同一侧时，位于外侧的连接线与相应叉指端部之间需要形成支撑结构93，由此可以光罩图形以确定支撑结构93的形成位置，从而避免间隙过大造成的结构不稳定的情形；在形成牺牲层95之后，需要对其进行平整；形成支撑结构93时，即在图形化形成第一叉指电极1、第二叉指电极2和/或第一连接线3、第二连接线4的过程中，还需要根据支撑结构93定义光照图形。另外，形成的支撑结构93将相应间隙分隔成多个子间隙；对应覆盖相应凸起及其四周被暴露的叉指电极和连接线的互连电极包括至少一子拱桥，对应覆盖相应凸起及其四周被暴露的叉指电极、连接线和支撑结构93的互连电极包括至少两子拱桥。牺牲层的材料及作用可参照上述隔离层的材料及作用，此处不再赘述。
参照图14-图15，在其他实施例中，支撑结构93与第一叉指电极1、第二叉指电极2、第一连接线3、第二连接线4的材料不同，则形成第一互连电极7、第二互连电极8的方法包括：先形成牺牲层95，填充第一间隙、第二间隙并覆盖第一叉指电极1、第二叉指电极2、第一连接线3和第二连接线4；再刻蚀牺牲层95，形成第三成型孔；填充第三成型孔，形成支撑材料层，参照图14。再刻蚀牺牲层95，形成第一凸起96、第二凸起97和支撑结构93，并暴露相应凸起四周的支撑结构93、叉指电极和连接线。再形成相应的互连电极，覆盖相应凸起以及相应凸起外周被暴露的叉指电极和连接线或叉指电极、连接线和支撑结构，参照图15。最后，去除第一凸起、第二凸起和牺牲层。
应当注意，支撑结构93还可以在形成第一凸起96、第二凸起97之后，形成第一互连电极7、第二互连电极8之前，刻蚀第一凸起96和/或第二凸起97，形成第三成型孔；形成支撑结构93，填充第三成型孔。去除第一凸起、第二凸起和牺牲层参照前文所述，此处不再赘述。
需要说明的是，本说明书中的各个实施例均采用相关的方式描述，各个实施例之间相同相似的部分互相参见即可，每个实施例重点说明的都是与其他实施例的不同之处。尤其，对于结构实施例而言，由于其基本相似于方法实施例，所以描述的比较简单，相关之处参见方法实施例的部分说明即可。
上述描述仅是对本发明较佳实施例的描述，并非对本发明范围的任何限定，本发明领域的普通技术人员根据上述揭示内容做的任何变更、修饰，均属于权利要求书的保护范围。

Claims (25)

  1. 一种薄膜表声波谐振器，其特征在于，包括：具有多个第一叉指的第一叉指电极、具有多个第二叉指的第二叉指电极，所述第一叉指与所述第二叉指间隔设置；第一连接线，至少位于所述第一叉指的其中一端，与所述第一叉指电连接；第二连接线，至少位于所述第二叉指的其中一端，与所述第二叉指电连接；所述第一连接线与所述第一叉指之间具有第一间隙，所述第一连接线与所述第一叉指通过跨越第一间隙的第一互连电极连接；和/或，所述第二连接线与所述第二叉指之间具有第二间隙，所述第二连接线与所述第二叉指通过跨越第二间隙的第二互连电极连接。
  2. 根据权利要求1所述的薄膜表声波谐振器，其特征在于，所述第一叉指的两端分别设有所述第一连接线，所述第一叉指的一端通过所述第一互连电极与所述一端的第一连接线电连接，或者，所述第一叉指的一端与所述第一连接线伪互连，或者，所述第一叉指的一端与第一连接线接触电连接。
  3. 根据权利要求1所述的薄膜表声波谐振器，其特征在于，所述第二叉指的两端分别设有所述第二连接线，所述第二叉指的一端通过所述第二互连电极与所述一端的第二连接线电连接，或者，所述第二叉指的一端与所述第二连接线通过所述第二互连电极伪互连，或者，所述第二叉指的一端与第二连接线接触电连接。
  4. 根据权利要求1所述的薄膜表声波谐振器，其特征在于，所述第一互连电极包括远离所述第一间隙凸起的第一拱形桥结构，所述第一拱形桥结构内表面围成第一空隙，所述第一空隙与所述第一间隙相对；和/或，所述第二互连电极包括远离所述第二间隙凸起的第二拱形桥结构，所述第二形桥结构内表面围成第二空隙，所述第二空隙与所述第二间隙相对。
  5. 根据权利要求4所述的薄膜表声波谐振器，其特征在于，所述第一拱形桥结构至少包括一子拱桥，相邻子拱桥之间连接部位下方设置支撑结构；和/或，所述第二拱形桥结构至少包括一子拱桥，相邻子拱桥之间连接部位下方设置支撑结构。
  6. 根据权利要求5所述的薄膜表声波谐振器，其特征在于，所述支撑结构将相应间隙分隔为至少两个相邻的子间隙，所述子拱桥内表面围成空隙，所述空隙与所述子间隙一一相对。
  7. 根据权利要求1所述的薄膜表声波谐振器，其特征在于，与所述第一叉指电连接的第一连接线、与所述第二叉指电连接的第二连接线位于同一侧或不同侧。
  8. 根据权利要求1所述的薄膜表声波谐振器，其特征在于，位于同一侧的第一连接线、第二连接线，其中之一位于另一的外侧，位于内侧的连接线穿过外侧的连接线与相应的叉指之间的间隙；位于外侧的连接线与相应的叉指连接的互连电极包括第一子拱桥和第二子拱桥，所述第一子拱桥和所述第二子拱桥相邻部位下方设支撑结构，所述第二子拱桥位于外侧且横跨内侧的支撑结构与外侧的连接线连接。
  9. 根据权利要求1所述的薄膜表声波谐振器，其特征在于，所述第一叉指的两端分别设有所述第一连接线，所述第二叉指的两端分别设有所述第二连接线，位于第一同侧的所述第一连接线设置于所述第二连接线的内侧，位于第二同侧的所述第一连接线设置于所述第二连接线的外侧。
  10. 根据权利要求9所述的薄膜表声波谐振器，其特征在于，设置于外侧的连接线与相应叉指连接的互连电极包括第一子拱桥和第二子拱桥，所述第一子拱桥和所述第二子拱桥相邻部位下方设支撑结构，所述第一子拱桥位于内侧且横跨内侧的叉指与外侧的支撑结构连接，所述第二子拱桥位于外侧且横跨内侧的支撑结构与外侧的连接线连接；设置于内侧的连接线与相应叉指连接的互连电极包括第三子拱桥，所述第三子拱桥横跨内侧的叉指与外侧的连接线连接；或者，设置于外侧的连接线与相应叉指连接的互连电极包括第一子拱桥和第二子拱桥，所述第一子拱桥和所述第二子拱桥相邻部位下方设支撑结构，所述第一子拱桥位于内侧且横跨内侧的叉指与外侧的支撑结构连接，所述第二子拱桥位于外侧且横跨内侧的支撑结构与外侧的连接线连接；设置于内侧的连接线与相应叉指连接的互连电极包括第三子拱桥和第四子拱桥，所述第一子拱桥和所述第二子拱桥相邻部位下方设支撑结构，所述第三子拱桥位于内侧且横跨内侧的叉指与外侧的支撑结构连接，所述第四子拱桥位于外侧且横跨内侧的支撑结构与外侧的连接线连接。
  11. 根据权利要求1所述的薄膜表声波谐振器，其特征在于，所述第一互连电极的阻抗低于所述第一叉指的阻抗，所述第二互连电极的阻抗低于所述第二叉指的阻抗。
  12. 根据权利要求1所述的薄膜表声波谐振器，其特征在于，所述第一互连电极、所述第二互连电极的材料为金属材料，所述金属材料包括金、银、钨、铂、铝、铜、钛、锡、镍中的一种或多种。
  13. 根据权利要求1所述的薄膜表声波谐振器，其特征在于，所述第一连接线面向所述第一互连电极的一面与所述第一叉指面向所述第一互连电极的一面齐平；和/或，
    所述第二连接线面向所述第二互连电极的一面与所述第二叉指面向所述第二互连电极的一面齐平。
  14. 根据权利要求1所述的薄膜表声波谐振器，其特征在于，所述第一叉指、所述第二叉指的材料包括金、银、钨、铂、铝、铜中的一种或多种的组合。
  15. 根据权利要求1所述的薄膜表声波谐振器，其特征在于，还包括压电层，所述第一互连电极、所述第二互连电极、所述第一连接线和所述第二连接线均设置于所述压电层上。
  16. 根据权利要求15所述的薄膜表声波谐振器，其特征在于，所述压电层的材料包括氮化铝、氧化锌、锆钛酸铅、铌酸锂、石英、铌酸钾或钽酸锂。
  17. 根据权利要求15所述的薄膜表声波谐振器，其特征在于，还包括与所述压电层键合设置的基板。
  18. 一种薄膜表声波谐振器的制造方法，其特征在于，包括：提供压电层；在所述压电层上形成具有多个第一叉指的第一叉指电极、具有多个第二叉指的第二叉指电极，所述第一叉指和所述第二叉指间隔设置；形成第一连接线，所述第一连接线至少形成于所述第一叉指的其中一端，且与所述第一叉指之间具有第一间隙；和/或，形成第二连接线，所述第二连接线至少形成于所述第二叉指的其中一端，且与所述第二叉指之间具有第二间隙；形成第一互连电极，所述第一互连电极跨越所述第一间隙并电连接所述第一叉指和所述第一连接线；形成第二互连电极，所述第二互连电极跨越所述第二间隙并电连接所述第二叉指和所述第二连接线。
  19. 根据权利要求18所述的薄膜表声波谐振器的制造方法，其特征在于，所述第一连接线、所述第二连接线、所述第一叉指电极和所述第二叉指电极的材料相同，形成第一连接线、所述第二连接线、所述第一叉指电极和所述第二叉指电极的方法包括：在所述压电层上形成导电层；图形化所述导电层以形成所述第一连接线、所述第二连接线、所述第一叉指电极和所述第二叉指电极。
  20. 根据权利要求18所述的薄膜表声波谐振器的制造方法，其特征在于，所述第一连接线、所述第二连接线、所述第一叉指电极和所述第二叉指电极的材料不同，形成所述第一连接线、所述第二连接线、所述第一叉指电极和所述第二叉指电极的方法包括：在所述压电层上形成第一导电层，图形化所述第一导电层以形成所述第一叉指电极、所述第二叉指电极；
    在所述压电层上形成第二导电层，图形化所述第二导电层以形成所述第一连接线和所述第二连接线。
  21. 根据权利要求20所述的薄膜表声波谐振器的制造方法，其特征在于，形成所述第一叉指电极、所述第二叉指电极后，利用剥离工艺形成所述第一连接线、所述第二连接线，包括：沉积形成隔离层，覆盖所述第一叉指电极、所述第二叉指电极和所述压电层；图形化所述隔离层，形成第一成型孔；形成所述第二导电层，填充所述第一成型孔并覆盖所述隔离层；去除位于所述隔离层上的第二导电层、去除所述隔离层，形成所述第一连接线和所述第二连接线。
  22. 根据权利要求20所述的薄膜表声波谐振器的制造方法，其特征在于，形成所述第一连接线、所述第二连接线之后，利用剥离工艺形成所述第一叉指电极、所述第二叉指电极，包括：沉积形成隔离层，覆盖所述第一连接线、所述第二连接线和所述压电层；图形化所述隔离层，形成第二成型孔；形成所述第二导电层，填充所述第二成型孔并覆盖所述隔离层；
    去除位于所述隔离层上的第二导电层、去除所述隔离层；图形化位于所述第二成型孔内的第二导电层，形成所述第一叉指电极和所述第二叉指电极。
  23. 根据权利要求18所述的薄膜表声波谐振器的制造方法，其特征在于，形成叉指电极和所述连接线后，形成所述第一互连电极、所述第二互连电极，所述第一互连电极和/或所述第二互连电极包括至少一子拱桥，相邻子拱桥之间形成支撑结构，形成方法包括：形成支撑结构，以将相应间隙分隔成多个子间隙；形成牺牲层，填充所述第一间隙、所述第二间隙并覆盖所述第一叉指电极、所述第二叉指电极、所述第一连接线和所述第二连接线；刻蚀所述牺牲层，形成第一凸起和第二凸起并暴露相应凸起四周的叉指电极和连接线或叉指电极、连接线和所述支撑结构；形成相应互连电极，覆盖相应凸起以及相应凸起外周被暴露的叉指电极和所述连接线或叉指电极、连接线和所述支撑结构；去除所述第一凸起、所述第二凸起和所述牺牲层。
  24. 根据权利要求23所述的薄膜表声波谐振器的制造方法，其特征在于，所述支撑结构与所述第一叉指电极、所述第二叉指电极和/或形成所述第一连接线、所述第二连接线的材料相同，形成所述支撑结构的方法包括：在形成所述第一叉指电极、所述第二叉指电极和/或形成所述第一连接线、所述第二连接线时，形成所述支撑结构。
  25. 根据权利要求23所述的薄膜表声波谐振器的制造方法，其特征在于，所述支撑结构与所述第一叉指电极、所述第二叉指电极、所述第一连接线、所述第二连接线的材料不同，形成所述支撑结构的方法包括：在形成所述第一凸起、第二凸起之前，刻蚀所述牺牲层，形成第三成型孔；填充所述第三成型孔，形成支撑材料层；在形成所述第一凸起、第二凸起时，刻蚀所述支撑材料层，形成所述支撑结构；或者，在形成所述第一凸起、第二凸起之后，形成所述第一互连电极、所述第二互连电极之前，刻蚀所述第一凸起和/或所述第二凸起，形成第三成型孔；形成支撑结构，填充所述第三成型孔。
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Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20160373084A1 (en) * 2015-06-19 2016-12-22 Taiyo Yuden Co., Ltd. Surface acoustic wave device and filter
CN208028861U (zh) * 2018-05-30 2018-10-30 扬州大学 一种温控双频声表面波谐振器
CN109004914A (zh) * 2018-07-11 2018-12-14 开元通信技术（厦门）有限公司 一种声表面波器件及其制备方法
CN110114973A (zh) * 2016-12-26 2019-08-09 株式会社村田制作所 弹性波装置

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20160373084A1 (en) * 2015-06-19 2016-12-22 Taiyo Yuden Co., Ltd. Surface acoustic wave device and filter
CN110114973A (zh) * 2016-12-26 2019-08-09 株式会社村田制作所 弹性波装置
CN208028861U (zh) * 2018-05-30 2018-10-30 扬州大学 一种温控双频声表面波谐振器
CN109004914A (zh) * 2018-07-11 2018-12-14 开元通信技术（厦门）有限公司 一种声表面波器件及其制备方法

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