WO2022080433A1 - Dispositif à ondes élastiques et son procédé de fabrication - Google Patents

Dispositif à ondes élastiques et son procédé de fabrication Download PDF

Info

Publication number
WO2022080433A1
WO2022080433A1 PCT/JP2021/037964 JP2021037964W WO2022080433A1 WO 2022080433 A1 WO2022080433 A1 WO 2022080433A1 JP 2021037964 W JP2021037964 W JP 2021037964W WO 2022080433 A1 WO2022080433 A1 WO 2022080433A1
Authority
WO
WIPO (PCT)
Prior art keywords
elastic wave
wave device
electrode
piezoelectric layer
electrodes
Prior art date
Application number
PCT/JP2021/037964
Other languages
English (en)
Japanese (ja)
Inventor
和則 井上
優太 石井
Original Assignee
株式会社村田製作所
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 株式会社村田製作所 filed Critical 株式会社村田製作所
Publication of WO2022080433A1 publication Critical patent/WO2022080433A1/fr

Links

Images

Classifications

    • 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
    • H03H3/08—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 resonators or networks using surface acoustic waves
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
    • H03H9/15—Constructional features of resonators consisting of piezoelectric or electrostrictive material
    • H03H9/17—Constructional features of resonators consisting of piezoelectric or electrostrictive material having a single resonator
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
    • H03H9/00—Networks comprising electromechanical or electro-acoustic devices; Electromechanical resonators
    • H03H9/25—Constructional features of resonators using surface acoustic waves

Definitions

  • the present disclosure relates to an elastic wave device having a piezoelectric layer containing lithium niobate or lithium tantalate.
  • Patent Document 1 describes an elastic wave device.
  • a cavity is provided between the support substrate and the piezoelectric layer.
  • the structure around the cavity provided in the support substrate may be damaged.
  • the present disclosure has been made in view of the above, and an object of the present invention is to provide an elastic wave device and a method for manufacturing an elastic wave device that suppresses damage to a structure around a cavity provided in a support substrate. ..
  • the elastic wave device is an elastic wave device having a mounting substrate having wiring, an elastic wave element mounted on the mounting board, and a cover member covering the elastic wave element, and the elastic wave device.
  • the element includes a piezoelectric layer having a first main surface and a second main surface opposite to the first main surface, electrodes provided on the first main surface of the piezoelectric layer, and the piezoelectric layer.
  • a support substrate laminated on a second main surface is provided, the first main surface of the piezoelectric layer is arranged to face the mounting substrate, and a part of the support substrate penetrates the support substrate.
  • a cavity is provided, and at least a part of the electrode is provided so as to overlap the cavity when viewed in plan from the first main surface, and the cover member covers the cavity of the support substrate. At the same time, the piezoelectric layer and the side surface of the support substrate are covered and connected to the mounting substrate.
  • the method for manufacturing an elastic wave device is a method for manufacturing an elastic wave device having a mounting board having wiring, an elastic wave element mounted on the mounting board, and a cover member covering the elastic wave element.
  • FIG. 1A is a perspective view showing an elastic wave device of the first embodiment.
  • FIG. 1B is a plan view showing the electrode structure of the first embodiment.
  • FIG. 2 is a cross-sectional view of a portion of FIG. 1A along line II-II.
  • FIG. 3A is a schematic cross-sectional view for explaining a Lamb wave propagating in the piezoelectric layer of the comparative example.
  • FIG. 3B is a schematic cross-sectional view for explaining a bulk wave in a thickness slip mode propagating in the piezoelectric layer of the first embodiment.
  • FIG. 4 is a schematic cross-sectional view for explaining the amplitude direction of the bulk wave in the thickness slip mode propagating through the piezoelectric layer of the first embodiment.
  • FIG. 1A is a perspective view showing an elastic wave device of the first embodiment.
  • FIG. 1B is a plan view showing the electrode structure of the first embodiment.
  • FIG. 2 is a cross-sectional view of a portion of FIG. 1A along line
  • FIG. 5 is an explanatory diagram showing an example of resonance characteristics of the elastic wave device of the first embodiment.
  • FIG. 6 shows d / 2p as a resonator in the elastic wave apparatus of the first embodiment, where p is the center-to-center distance or the average distance between the centers of adjacent electrodes and d is the average thickness of the piezoelectric layer. It is explanatory drawing which shows the relationship with the specific band of.
  • FIG. 7 is a plan view showing an example in which a pair of electrodes is provided in the elastic wave device of the first embodiment.
  • FIG. 8 is a reference diagram showing an example of resonance characteristics of the elastic wave device of the first embodiment.
  • FIG. 9 is an explanatory diagram showing the relationship between the specific band when a large number of elastic wave resonators are configured and the phase rotation amount of the impedance of the spurious standardized at 180 degrees as the size of the spurious.
  • FIG. 10 is an explanatory diagram showing the relationship between d / 2p, the metallization ratio MR, and the specific band.
  • FIG. 11 is an explanatory diagram showing a map of the specific band with respect to Euler angles (0 °, ⁇ , ⁇ ) of LiNbO 3 when d / p is brought as close to 0 as possible.
  • FIG. 12 is a plan view showing an elastic wave element included in the elastic wave device of the first embodiment.
  • FIG. 13 is a cross-sectional view of a portion of FIG.
  • FIG. 14 is an explanatory diagram for explaining a method for manufacturing the elastic wave device of the first embodiment.
  • FIG. 15 is an explanatory diagram for explaining a method of manufacturing an elastic wave device according to a first modification of the first embodiment.
  • FIG. 16 is a plan view showing an elastic wave element included in the elastic wave device according to the second modification of the first embodiment.
  • FIG. 17 is a plan view showing an elastic wave element included in the elastic wave device of the second embodiment.
  • FIG. 18 is a cross-sectional view of a portion of FIG. 17 along the line XVIII-XVIII.
  • FIG. 19 is a cross-sectional view showing an elastic wave element included in the elastic wave device according to the third modification of the second embodiment.
  • FIG. 20 is an explanatory diagram for explaining a method of manufacturing the elastic wave device of the second embodiment.
  • FIG. 21 is a plan view showing an elastic wave element included in the elastic wave device of the third embodiment.
  • FIG. 22 is a cross-sectional view of a portion of FIG. 21 along the line XXII-XXII.
  • FIG. 23 is a plan view showing an elastic wave element included in the elastic wave device according to the fourth modification of the third embodiment.
  • FIG. 24 is a cross-sectional view showing an elastic wave device according to a fifth modification of the third embodiment.
  • FIG. 25 is an explanatory diagram for explaining a method of manufacturing an elastic wave device according to a sixth modification of the third embodiment.
  • FIG. 26 is a plan view for explaining a method of manufacturing an elastic wave device according to a sixth modification of the third embodiment.
  • FIG. 1A is a perspective view showing an elastic wave device of the first embodiment.
  • FIG. 1B is a plan view showing the electrode structure of the first embodiment.
  • the elastic wave device 1 of the first embodiment has a piezoelectric layer 2 made of LiNbO 3 .
  • the piezoelectric layer 2 may be made of LiTaO 3 .
  • the cut angle of LiNbO 3 and LiTaO 3 is a Z cut in the first embodiment.
  • the cut angle of LiNbO 3 or LiTaO 3 may be a rotary Y cut or an X cut. Propagation directions of Y propagation and X propagation ⁇ 30 ° are preferable.
  • the thickness of the piezoelectric layer 2 is not particularly limited, but is preferably 50 nm or more and 1000 nm or less in order to effectively excite the thickness slip mode.
  • the piezoelectric layer 2 has a first main surface 2a facing each other in the Z direction and a second main surface 2b.
  • the electrode 3 and the electrode 4 are provided on the first main surface 2a.
  • the electrode 3 is an example of the "first electrode”
  • the electrode 4 is an example of the "second electrode”.
  • a plurality of electrodes 3 are connected to the first bus bar 5.
  • the plurality of electrodes 4 are connected to the second bus bar 6.
  • the plurality of electrodes 3 and the plurality of electrodes 4 are interleaved with each other.
  • the electrode 3 and the electrode 4 have a rectangular shape and have a length direction.
  • the electrode 3 and the electrode 4 adjacent to the electrode 3 face each other in a direction orthogonal to the length direction.
  • the length direction of the electrode 3 and the electrode 4 and the direction orthogonal to the length direction of the electrode 3 and the electrode 4 are all directions intersecting with each other in the thickness direction of the piezoelectric layer 2. Therefore, it can be said that the electrode 3 and the electrode 4 adjacent to the electrode 3 face each other in a direction intersecting with each other in the thickness direction of the piezoelectric layer 2.
  • the thickness direction of the piezoelectric layer 2 is the Z direction
  • the direction orthogonal to the length direction of the electrode 3 and the electrode 4 is the X direction
  • the length direction of the electrode 3 and the electrode 4 is the Y direction.
  • the length directions of the electrodes 3 and 4 may be replaced with the directions orthogonal to the length directions of the electrodes 3 and 4 shown in FIGS. 1A and 1B. That is, in FIGS. 1A and 1B, the electrodes 3 and 4 may be extended in the direction in which the first bus bar 5 and the second bus bar 6 are extended. In that case, the first bus bar 5 and the second bus bar 6 extend in the direction in which the electrodes 3 and 4 extend in FIGS. 1A and 1B. Then, a pair of structures in which the electrode 3 connected to one potential and the electrode 4 connected to the other potential are adjacent to each other are provided in a plurality of pairs in a direction orthogonal to the length direction of the electrodes 3 and 4. ing.
  • the case where the electrode 3 and the electrode 4 are adjacent to each other does not mean that the electrode 3 and the electrode 4 are arranged so as to be in direct contact with each other, but that the electrode 3 and the electrode 4 are arranged so as to be spaced apart from each other. Point to. Further, when the electrode 3 and the electrode 4 are adjacent to each other, the electrode connected to the hot electrode or the ground electrode, including the other electrode 3 and the electrode 4, is not arranged between the electrode 3 and the electrode 4. This logarithm does not have to be an integer pair, and may be 1.5 pairs, 2.5 pairs, or the like.
  • the distance between the centers between the electrode 3 and the electrode 4, that is, the pitch is preferably in the range of 1 ⁇ m or more and 10 ⁇ m or less.
  • the center-to-center distance between the electrode 3 and the electrode 4 is the center of the width dimension of the electrode 3 in the direction orthogonal to the length direction of the electrode 3 and the electrode 4 in the direction orthogonal to the length direction of the electrode 4. It is the distance connecting the center of the width dimension of.
  • the electrodes 3 and 4 when there are a plurality of at least one of the electrodes 3 and 4 (when the electrodes 3 and 4 are a pair of electrodes and there are 1.5 or more pairs of electrodes), the electrodes 3 and 4
  • the center-to-center distance refers to the average value of the center-to-center distances of 1.5 pairs or more of the electrodes 3, the adjacent electrodes 3 and the electrodes 4.
  • the width of the electrode 3 and the electrode 4, that is, the dimensions of the electrode 3 and the electrode 4 in the facing direction are preferably in the range of 150 nm or more and 1000 nm or less.
  • the direction orthogonal to the length direction of the electrodes 3 and 4 is the direction orthogonal to the polarization direction of the piezoelectric layer 2. This does not apply when a piezoelectric material having another cut angle is used as the piezoelectric layer 2.
  • “orthogonal” is not limited to the case of being strictly orthogonal, and is substantially orthogonal (the angle formed by the direction orthogonal to the length direction of the electrodes 3 and 4 and the polarization direction is, for example, 90 ° ⁇ 10 °). ) May be.
  • FIG. 2 is a cross-sectional view of a portion of FIG. 1A along the line II-II.
  • a support member 8 (support substrate) is laminated on the second main surface 2b side of the piezoelectric layer 2 via an intermediate layer 7.
  • the intermediate layer 7 and the support member 8 have a frame-like shape and have openings 7a and 8a as shown in FIG. As a result, the cavity 9 (air gap) is formed.
  • the cavity 9 is provided so as not to interfere with the vibration of the excitation region C of the piezoelectric layer 2. Therefore, the support member 8 is laminated on the second main surface 2b via the intermediate layer 7 at a position where the support member 8 does not overlap with the portion where the at least one pair of electrodes 3 and the electrodes 4 are provided.
  • the intermediate layer 7 may not be provided. Therefore, the support member 8 may be directly or indirectly laminated on the second main surface 2b of the piezoelectric layer 2.
  • the intermediate layer 7 is an insulating layer and is made of silicon oxide.
  • the intermediate layer 7 can be formed of an appropriate insulating material such as silicon nitride or alumina in addition to silicon oxide.
  • the support member 8 is also called a support substrate and is formed of Si.
  • the plane orientation of Si on the surface of the piezoelectric layer 2 side may be (100), (110), or (111).
  • high resistance Si having a resistivity of 4 k ⁇ or more is desirable.
  • the support member 8 can also be configured by using an appropriate insulating material or semiconductor material.
  • the material of the support member 8 include piezoelectric materials such as aluminum oxide, lithium tantalate, lithium niobate, and crystal, alumina, magnesia, sapphire, silicon nitride, aluminum nitride, silicon carbide, zirconia, cordierite, mulite, and steer.
  • Various ceramics such as tight and forsterite, dielectrics such as diamond and glass, and semiconductors such as gallium nitride can be used.
  • the plurality of electrodes 3, the electrodes 4, the first bus bar 5, and the second bus bar 6 are made of an appropriate metal or alloy such as an Al or AlCu alloy.
  • the electrode 3, the electrode 4, the first bus bar 5, and the second bus bar 6 have a structure in which an Al film is laminated on a Ti film. An adhesive layer other than the Ti film may be used.
  • an AC voltage is applied between the plurality of electrodes 3 and the plurality of electrodes 4. More specifically, an AC voltage is applied between the first bus bar 5 and the second bus bar 6. As a result, it is possible to obtain resonance characteristics using the bulk wave of the thickness slip mode excited in the piezoelectric layer 2.
  • the thickness of the piezoelectric layer 2 when the thickness of the piezoelectric layer 2 is d, the distance between the centers of the plurality of pairs of electrodes 3, the adjacent electrodes 3 of the electrodes 4, and the electrodes 4 is p, d / p is It is said to be 0.5 or less. Therefore, the bulk wave in the thickness slip mode is effectively excited, and good resonance characteristics can be obtained. More preferably, d / p is 0.24 or less, in which case even better resonance characteristics can be obtained.
  • the electrodes 3 and 4 are 1.5 pairs.
  • the distance p between the centers of the adjacent electrodes 3 and 4 is the average distance between the centers of the adjacent electrodes 3 and 4.
  • the elastic wave device 1 of the first embodiment has the above configuration, the Q value is unlikely to decrease even if the logarithm of the electrodes 3 and 4 is reduced in order to reduce the size. This is because it is a resonator that does not require reflectors on both sides and has little propagation loss. Further, the reason why the above reflector is not required is that the bulk wave in the thickness slip mode is used.
  • FIG. 3A is a schematic cross-sectional view for explaining a Lamb wave propagating in the piezoelectric layer of the comparative example.
  • FIG. 3B is a schematic cross-sectional view for explaining a bulk wave in a thickness slip mode propagating in the piezoelectric layer of the first embodiment.
  • FIG. 4 is a schematic cross-sectional view for explaining the amplitude direction of the bulk wave in the thickness slip mode propagating through the piezoelectric layer of the first embodiment.
  • FIG. 3A is an elastic wave device as described in Patent Document 1, in which a ram wave propagates in a piezoelectric layer.
  • the wave propagates in the piezoelectric layer 201 as indicated by an arrow.
  • the piezoelectric layer 201 has a first main surface 201a and a second main surface 201b, and the thickness direction connecting the first main surface 201a and the second main surface 201b is the Z direction. ..
  • the X direction is the direction in which the electrode fingers of the IDT electrodes are lined up.
  • the wave propagates in the X direction as shown in the figure.
  • the piezoelectric layer 201 vibrates as a whole because it is a plate wave, the wave propagates in the X direction, so reflectors are arranged on both sides to obtain resonance characteristics. Therefore, a wave propagation loss occurs, and the Q value decreases when the size is reduced, that is, when the logarithm of the electrode fingers is reduced.
  • the wave is generated by the first main surface 2a and the second main surface 2a of the piezoelectric layer 2. It propagates substantially in the direction connecting the surface 2b, that is, in the Z direction, and resonates. That is, the X-direction component of the wave is significantly smaller than the Z-direction component. And since the resonance characteristic is obtained by the propagation of the wave in the Z direction, the reflector is not required. Therefore, there is no propagation loss when propagating to the reflector. Therefore, even if the logarithm of the electrode pair consisting of the electrodes 3 and 4 is reduced in order to promote miniaturization, the Q value is unlikely to decrease.
  • the amplitude directions of the bulk waves in the thickness slip mode are the first region 451 included in the excitation region C (see FIG. 1B) of the piezoelectric layer 2 and the second region included in the excitation region C. It is the opposite of 452.
  • FIG. 4 schematically shows a bulk wave when a voltage at which the electrode 4 has a higher potential than that of the electrode 3 is applied between the electrode 3 and the electrode 4.
  • the first region 451 is a region of the excitation region C between the virtual plane VP1 orthogonal to the thickness direction of the piezoelectric layer 2 and dividing the piezoelectric layer 2 into two, and the first main surface 2a.
  • the second region 452 is a region of the excitation region C between the virtual plane VP1 and the second main surface 2b.
  • the elastic wave device 1 At least one pair of electrodes consisting of the electrode 3 and the electrode 4 is arranged, but since the wave is not propagated in the X direction, the logarithm of the electrode pair consisting of the electrode 3 and the electrode 4 Does not necessarily have to be multiple pairs. That is, it is only necessary to provide at least one pair of electrodes.
  • the electrode 3 is an electrode connected to a hot potential
  • the electrode 4 is an electrode connected to a ground potential.
  • the electrode 3 may be connected to the ground potential and the electrode 4 may be connected to the hot potential.
  • at least one pair of electrodes is an electrode connected to a hot potential or an electrode connected to a ground potential as described above, and is not provided with a floating electrode.
  • FIG. 5 is an explanatory diagram showing an example of resonance characteristics of the elastic wave device of the first embodiment.
  • the design parameters of the elastic wave device 1 that has obtained the resonance characteristics shown in FIG. 5 are as follows.
  • Piezoelectric layer 2 LiNbO 3 with Euler angles (0 °, 0 °, 90 °) Piezoelectric layer 2 thickness: 400 nm
  • Excitation region C (see FIG. 1B) length: 40 ⁇ m
  • the excitation region C (see FIG. 1B) is a region where the electrode 3 and the electrode 4 overlap when viewed in the X direction orthogonal to the length direction of the electrode 3 and the electrode 4.
  • the length of the excitation region C is a dimension along the length direction of the electrodes 3 and 4 of the excitation region C.
  • the distance between the electrodes of the electrode pair consisting of the electrodes 3 and 4 is the same for the plurality of pairs. That is, the electrodes 3 and 4 are arranged at equal pitches.
  • d / p is 0.5 or less, more preferably 0.24. It is as follows. This will be described with reference to FIG.
  • FIG. 6 shows d / 2p as a resonator in the elastic wave apparatus of the first embodiment, where p is the center-to-center distance or the average distance between the centers of adjacent electrodes and d is the average thickness of the piezoelectric layer. It is explanatory drawing which shows the relationship with the specific band of.
  • the ratio band is less than 5% even if d / p is adjusted.
  • the specific band can be set to 5% or more by changing d / p within that range. That is, a resonator having a high coupling coefficient can be constructed.
  • the specific band can be increased to 7% or more.
  • a resonator having a wider specific band can be obtained, and a resonator having a higher coupling coefficient can be realized. Therefore, it can be seen that by setting d / p to 0.5 or less, a resonator having a high coupling coefficient can be configured by utilizing the bulk wave in the thickness slip mode.
  • At least one pair of electrodes may be one pair, and in the case of a pair of electrodes, p is the distance between the centers of the adjacent electrodes 3 and 4. In the case of 1.5 pairs or more of electrodes, the average distance between the centers of the adjacent electrodes 3 and 4 may be p.
  • the thickness d of the piezoelectric layer if the piezoelectric layer 2 has a thickness variation, a value obtained by averaging the thickness may be adopted.
  • FIG. 7 is a plan view showing an example in which a pair of electrodes is provided in the elastic wave device of the first embodiment.
  • a pair of electrodes having an electrode 3 and an electrode 4 is provided on the first main surface 2a of the piezoelectric layer 2.
  • K in FIG. 7 is an intersection width.
  • the logarithm of the electrodes may be one pair. Even in this case, if the d / p is 0.5 or less, the bulk wave in the thickness slip mode can be effectively excited.
  • the excitation region C which is a region in which any of the adjacent electrodes 3 and 4 are overlapped when viewed in the opposite direction, is provided. It is desirable that the metallization ratio MR of the adjacent electrodes 3 and 4 satisfies MR ⁇ 1.75 (d / p) +0.075. In that case, spurious can be effectively reduced. This will be described with reference to FIGS. 8 and 9.
  • FIG. 8 is a reference diagram showing an example of resonance characteristics of the elastic wave device of the first embodiment.
  • the spurious indicated by the arrow B appears between the resonance frequency and the antiresonance frequency.
  • the metallization ratio MR will be described with reference to FIG. 1B.
  • the excitation region C is a region in the electrode 4 where the electrode 3 and the electrode 4 overlap with the electrode 4 in the electrode 3 when viewed in a direction orthogonal to the length direction of the electrode 3 and the electrode 4, that is, in an opposite direction. It is a region where the electrode 3 overlaps and a region where the electrode 3 and the electrode 4 overlap in the region between the electrode 3 and the electrode 4.
  • the metallization ratio MR is a ratio of the area of the metallization portion to the area of the excitation region C.
  • the ratio of the metallization portion included in the total excitation region C to the total area of the excitation region C may be MR.
  • FIG. 9 shows the specific band of the elastic wave apparatus of the first embodiment when a large number of elastic wave resonators are configured, and the phase rotation amount of the impedance of the spurious standardized at 180 degrees as the size of the spurious. It is explanatory drawing which shows the relationship of.
  • the specific band was adjusted by variously changing the film thickness of the piezoelectric layer 2 and the dimensions of the electrodes 3 and 4. Further, FIG. 9 shows the result when the piezoelectric layer 2 made of Z-cut LiNbO 3 is used, but the same tendency is obtained when the piezoelectric layer 2 having another cut angle is used.
  • the spurious is as large as 1.0.
  • the specific band exceeds 0.17, that is, when it exceeds 17%, the pass band even if a large spurious having a spurious level of 1 or more changes the parameters constituting the specific band. Appears in. That is, as shown in the resonance characteristic of FIG. 8, a large spurious indicated by an arrow B appears in the band. Therefore, the specific band is preferably 17% or less. In this case, the spurious can be reduced by adjusting the film thickness of the piezoelectric layer 2, the dimensions of the electrodes 3 and 4, and the like.
  • FIG. 10 is an explanatory diagram showing the relationship between d / 2p, the metallization ratio MR, and the specific band.
  • various elastic wave devices 1 having different MRs from d / 2p were configured, and the specific band was measured.
  • the portion shown with hatching on the right side of the broken line D in FIG. 10 is a region having a specific band of 17% or less.
  • FIG. 11 is an explanatory diagram showing a map of the specific band with respect to Euler angles (0 °, ⁇ , ⁇ ) of LiNbO 3 when d / p is brought as close to 0 as possible.
  • the portion shown with hatching in FIG. 11 is a region where a specific band of at least 5% or more can be obtained. When the range of the region is approximated, it becomes the range represented by the following equations (1), (2) and (3).
  • Equation (1) (0 ° ⁇ 10 °, 20 ° to 80 °, 0 ° to 60 ° (1- ( ⁇ -50) 2/900) 1/2 ) or (0 ° ⁇ 10 °, 20 ° to 80 °, [180] ° -60 ° (1- ( ⁇ -50) 2/900) 1/2 ] to 180 °).
  • Equation (2) (0 ° ⁇ 10 °, [180 ° -30 ° (1- ( ⁇ 90) 2/8100) 1/2 ] to 180 °, arbitrary ⁇ ).
  • the specific band can be sufficiently widened, which is preferable.
  • the bulk wave in the thickness slip mode is used.
  • the first electrode 3 and the second electrode 4 are adjacent electrodes, the thickness of the piezoelectric layer is d, and the distance between the centers of the first electrode and the second electrode is p. If so, d / p is set to 0.5 or less. As a result, the Q value can be increased even if the elastic wave device is miniaturized.
  • the piezoelectric layer 2 is formed of lithium niobate or lithium tantalate.
  • the first main surface 2a or the second main surface 2b of the piezoelectric layer 2 has a first electrode 3 and a second electrode 4 facing each other in a direction intersecting with each other in the thickness direction of the piezoelectric layer 2. It is desirable to cover the electrode 3 and the second electrode 4 with a protective film.
  • FIG. 12 is a plan view showing an elastic wave element included in the elastic wave device of the first embodiment.
  • FIG. 13 is a cross-sectional view of a portion of FIG. 12 along the line XIII-XIII. Note that FIG. 12 is a plan view of the piezoelectric layer 2 as viewed from the first main surface 2a side.
  • the elastic wave element 20 included in the elastic wave device 1 includes a piezoelectric layer 2, an electrode 3 provided on the first main surface 2a of the piezoelectric layer 2, an electrode 4, and a second of the piezoelectric layer 2. It has a support member 8 (support substrate) laminated on the main surface 2b of the above, a terminal 12, a wiring 13, and a bump 14.
  • the electrodes 3 and 4 are located at the center of the piezoelectric layer 2 in a plan view from a direction perpendicular to the first main surface 2a.
  • the plurality of terminals 12 are located at the four corners of the piezoelectric layer 2, and the plurality of bumps 14 are provided so as to overlap each of the plurality of terminals 12.
  • the plurality of terminals 12 and the plurality of bumps 14 are not limited to the configuration in which four each are provided, and may be five or more each.
  • the plurality of terminals 12 include a first terminal 12a and a second terminal 12b located diagonally.
  • the plurality of bumps 14 include a first bump 14a and a second bump 14b provided on the first terminal 12a and the second terminal 12b, respectively.
  • the plurality of electrodes 3 are electrically connected to the first terminal 12a and the first bump 14a via the first bus bar 5 and the first wiring 13a.
  • the plurality of electrodes 4 are electrically connected to the second terminal 12b and the second bump 14b via the second bus bar 6 and the second wiring 13b.
  • the first terminal 12a is a terminal that supplies a hot potential to the electrode 3
  • the second terminal 12b is a terminal that supplies a ground potential to the electrode 4.
  • the elastic wave device 1 includes a mounting substrate 30, an elastic wave element 20, and a cover member 22.
  • the mounting board 30 has a plurality of dielectric layers 31, electrode pads 32a, wiring 32b, mounting board terminals 32c, and vias 34.
  • the plurality of wirings 32b are provided between the layers of the plurality of dielectric layers 81.
  • the plurality of wirings 32b are not limited to the layers, and may be provided on the surface of the mounting substrate 30 facing the elastic wave element 20 or the surface opposite to the elastic wave element 20.
  • the electrode pad 32a is provided on the surface of the mounting substrate 30 facing the elastic wave element 20.
  • the mounting board terminal 32c is provided on the surface of the mounting board 30 opposite to the surface facing the elastic wave element 20.
  • the plurality of vias 34 are provided so as to penetrate each dielectric layer 31.
  • the electrode pad 32a, the wiring 32b, and the mounting board terminal 32c are electrically connected by the plurality of vias 34.
  • FIG. 13 shows a configuration in which the mounting substrate 30 is formed of two dielectric layers 31.
  • the present invention is not limited to this, and the mounting substrate 30 may have one layer or three or more dielectric layers 31.
  • the electrode pad 32a, the wiring 32b, and the mounting board terminal 32c may be simply referred to as the electrode 32.
  • the elastic wave element 20 is mounted on the mounting substrate 30. More specifically, in the piezoelectric layer 2 of the elastic wave element 20, the first main surface 2a is arranged so as to face the mounting substrate 30. The elastic wave element 20 is mounted on the electrode pad 32a of the mounting substrate 30 via the bump 14. As a result, a space is formed between the first main surface 2a of the piezoelectric layer 2 and the mounting substrate 30. The electrodes 3 and 4 are provided between the first main surface 2a of the piezoelectric layer 2 and the mounting substrate 30. More specifically, the elastic wave element 20 comprises a bump 14, a terminal 12, and a wiring 13 (see FIG. 12), an electrode 3 and an electrode 4, a piezoelectric layer 2, an intermediate layer 7, and a support member 8 on a mounting substrate 30. They are stacked in order.
  • An intermediate wiring layer 5a (or an intermediate wiring layer 6a) is provided between the terminal 12 and the wiring 13 (see FIG. 12) and the piezoelectric layer 2.
  • the terminal 12 and the wiring 13 are configured by laminating two metal layers.
  • the intermediate wiring layer 5a and the intermediate wiring layer 6a are formed in the same layer as the electrode 3, the electrode 4, the first bus bar 5, and the second bus bar 6, respectively.
  • the intermediate wiring layer 5a is electrically connected to the electrode 3 via the first bus bar 5.
  • the intermediate wiring layer 6a is electrically connected to the electrode 4 via the second bus bar 6.
  • the intermediate layer 7 and the support member 8 are laminated on the second main surface b of the piezoelectric layer 2.
  • a cavity 9 is formed in a region of the intermediate layer 7 and the support member 8 that overlaps at least the electrodes 3 and 4.
  • the cavity 9 is provided so as to penetrate the intermediate layer 7 and the support member 8 in the thickness direction.
  • the cover member 22 is provided so as to cover the elastic wave element 20.
  • the cover member 22 is a sealing member made of, for example, a resin or a metal.
  • the cover member 22 has a top plate 22a and a side plate 22b integrally formed with the top plate 22a.
  • the top plate 22a covers the support member 8 and the cavity 9.
  • the side plate 22b covers the side surfaces of the piezoelectric layer 2 and the support member 8.
  • the side plate 22b is provided so as to cover the periphery of the plurality of terminals 12 and the plurality of bumps 14 and is in contact with the mounting substrate 30. In this way, the cover member 22 covers the cavity 9 of the support member 8 and covers the side surfaces of the piezoelectric layer 2 and the support member 8 and is connected to the mounting substrate 30.
  • the top plate 22a of the cover member 22 is in contact with the upper surface of the support member 8. However, a gap may be provided between the top plate 22a of the cover member 22 and the upper surface of the support member 8. Further, the side plate 22b of the cover member 22 is arranged apart from the side surfaces of the piezoelectric layer 2 and the support member 8. However, the side plate 22b of the cover member 22 may be in contact with the side surfaces of the piezoelectric layer 2 and the support member 8.
  • the elastic wave device 1 of the present embodiment includes a mounting substrate 30 having a wiring 32b, an elastic wave element 20 mounted on the mounting substrate 30, and a cover member 22 covering the elastic wave element 20.
  • the elastic wave element 20 has a piezoelectric layer 2 having a first main surface 2a and a second main surface 2b opposite to the first main surface 2a, and a piezoelectric layer 2.
  • the electrode 3 and the electrode 4 provided on the first main surface 2a of the above are provided, and a support member 8 (support substrate) laminated on the second main surface 2b of the piezoelectric layer 2 is provided.
  • the first main surface 2a of the piezoelectric layer 2 is arranged so as to face the mounting substrate 30.
  • a hollow portion 9 penetrating the support member 8 is provided in a part of the support member 8.
  • the cover member 22 covers the cavity portion 9 of the support member 8 and has a piezoelectric layer. 2 and the support member 8 are covered and connected to the mounting board 30.
  • the elastic wave element 20 is arranged in the space surrounded by the mounting substrate 30 and the cover member 22. That is, the cavity 9 of the support member 8 provided on the second main surface 2b side of the piezoelectric layer 2 and the space formed between the first main surface 2a of the piezoelectric layer 2 and the mounting substrate 30 are formed. , It is provided in the same space surrounded by the mounting board 30 and the cover member 22.
  • the difference between the pressure applied to the space formed between the main surface 2a and the mounting substrate 30) is reduced, and damage to the structure around the cavity 9 can be suppressed.
  • the cover member 22 is arranged at a distance from at least a part of the upper surface and the side surface of the support member 8. According to this, it is possible to suppress the difference between the pressure applied to the cavity 9 and the pressure applied to the void on the first main surface 2a side of the piezoelectric layer 2.
  • FIG. 14 is an explanatory diagram for explaining a method for manufacturing the elastic wave device of the first embodiment.
  • FIG. 14 shows an example in which two elastic wave elements 20 are formed side by side with a gap on the piezoelectric layer 2 in order to make the drawing easier to see, in reality, the same piezoelectric layer is shown.
  • a plurality of three or more elastic wave elements 20 are formed on the 2 (bonded substrate described later).
  • the electrodes 3 and 4 are formed on the first main surface 2a of the piezoelectric layer 2 (step ST1).
  • the piezoelectric layer 2 is formed as a bonded substrate by bonding the intermediate layer 7 and the piezoelectric layer 2 on the support member 8 and grinding the piezoelectric layer 2 to a desired thickness.
  • the electrodes 3 and 4 are patterned by lift-off, etching, or the like. In the same process as the electrode 3 and the electrode 4, the first bus bar 5, the second bus bar 6, the intermediate wiring layer 5a, and the intermediate wiring layer 6a are also patterned.
  • the terminal 12 and the wiring 13 are formed on the intermediate wiring layer 5a and the intermediate wiring layer 6a (step ST2).
  • the terminals 12 and the wiring 13 are patterned by lift-off, etching, or the like.
  • a protective film may be provided on the first main surface 2a of the piezoelectric layer 2 so as to cover the electrodes 3 and 4.
  • the protective film is formed of an insulating material such as silicon oxide.
  • slits 2c and 7c are formed in the piezoelectric layer 2 and the intermediate layer 7 in the region overlapping the dicing line that divides the elastic wave element 20 into individual pieces (step ST3).
  • the slits 2c and 7c of the piezoelectric layer 2 and the intermediate layer 7 are formed by, for example, dry etching or the like.
  • the slits 2c and 7c are formed in a grid pattern around each of the elastic wave elements 20 in a plan view.
  • a cavity 9 penetrating the support member 8 and the intermediate layer 7 is formed (step ST4).
  • the support member 8 and the intermediate layer 7 are removed by, for example, etching or the like to form openings 7a and 8a.
  • the membrane structure of the piezoelectric layer 2 is formed in the region overlapping the electrodes 3 and 4.
  • the bump 14 is formed on the terminal 12 (step ST5).
  • the bump 14 is configured to include, for example, gold (Au) or a gold alloy.
  • a slit 8c is formed in the support member 8 in a region overlapping the dicing line, and the elastic wave element 20 is divided into individual pieces (step ST6).
  • step ST7 a plurality of elastic wave elements 20 are mounted side by side on one mounting substrate 30.
  • the first main surface 2a of the piezoelectric layer 2 is arranged so as to face the mounting substrate 30.
  • the bump 14 of the elastic wave element 20 and the electrode pad 32a of the mounting substrate 30 are joined by, for example, Au-Au bonding.
  • the cover member 22 is provided on the mounting substrate 30 so as to cover the plurality of elastic wave elements 20 (step ST8).
  • the cover member 22 is made of, for example, a resin material, and is provided so as to cover the support member 8 and the cavity 9 of the support member 8 and to cover the side surfaces of the support member 8 and the piezoelectric layer 2.
  • the cover member 22 is provided so as to surround each of the plurality of elastic wave elements 20 and is in contact with the mounting substrate 30. As a result, the space between the cover member 22 and the mounting substrate 30 is sealed.
  • the mounting substrate 30 and the cover member 22 are cut by dicing, and the elastic wave device 1 (elastic wave element 20) is divided into individual pieces (step ST9).
  • the intermediate layer 7 (insulating film), the piezoelectric layer 2, the electrode 3 and the electrode 4 are laminated in this order on the support member 8, and the support member 8 is used.
  • An elastic wave element forming step (steps ST1 to ST6) for forming an elastic wave element 20 having a cavity 9 formed in a part thereof, and a mounting step for mounting the elastic wave element 20 on a mounting substrate 30 having a wiring 32b.
  • FIG. 15 is an explanatory diagram for explaining a method of manufacturing an elastic wave device according to a first modification of the first embodiment.
  • the first modification of the first embodiment unlike the above-mentioned first embodiment, the case where the cover member 22A is formed by using metal will be described.
  • the elastic wave element forming steps (steps ST1 to ST6) are the same as those in FIG. 14, and the repeated description will be omitted.
  • the elastic wave element 20A is mounted on the mounting substrate 30 (step ST11). Similar to step ST7 (see FIG. 14) described above, the bump 14 of the elastic wave element 20A and the electrode pad 32a of the mounting substrate 30 are joined by, for example, Au-Au bonding.
  • the frame-shaped electrode 32d is provided on the mounting substrate 30 in a region overlapping the dicing line between the elastic wave elements 20A.
  • a cover member 22A in which the metal sheet 23 and the solder 24 are integrally formed is provided so as to cover the plurality of elastic wave elements 20A (step ST12).
  • the solder 24 is provided so as to be in contact with the elastic wave element 20A, and the metal sheet 23 covers the surface of the solder 24.
  • the reflow process is performed while the metal sheet 23 and the solder 24 are pressed against the mounting board 30 side.
  • the solder 24 is provided so as to cover the support member 8 and the cavity 9 of the support member 8 and also cover the side surfaces of the support member 8 and the piezoelectric layer 2. Further, the solder 24 is connected to the frame-shaped electrode 32d of the mounting substrate 30.
  • a slit SL is formed in the metal sheet 23 and the solder 24 in the region overlapping the dicing line, and the cover member 22A is divided into individual pieces for each elastic wave element 20 (step ST13).
  • the mounting substrate 30 is not divided into individual pieces, and the slit SL is also formed in a part of the dielectric layer 31 of the mounting substrate 30.
  • the metal layer 25 is provided so as to cover the metal sheet 23 and the solder 24 (step ST14).
  • nickel (Ni) is used for the metal layer 25, and the metal layer 25 is formed by plating.
  • the metal layer 25 is provided so as to cover the upper surface of the metal sheet 23 and the side surface of the solder 24 for each elastic wave element 20.
  • the cover member 22A of the first modification includes the solder 24, the metal sheet 23, and the metal layer 25.
  • the mounting substrate 30 is cut by dicing, and the elastic wave device 1A having the elastic wave element 20A is divided into individual pieces (step ST15).
  • the cover member 22A according to the first modification of the first embodiment can be combined with each embodiment and each modification described later.
  • FIG. 16 is a plan view showing an elastic wave element included in the elastic wave device according to the second modification of the first embodiment.
  • the elastic wave device 1B elastic wave element 20B
  • a plurality of cavity portions 9A and 9B are provided in the support member 8. The configuration to be used will be described.
  • a plurality of electrodes 3A, electrodes 4A, and a first bus bar 5A are formed on the first main surface 2a of the piezoelectric layer 2.
  • a first IDT electrode composed of a second bus bar 6A and a second IDT electrode composed of a plurality of electrodes 3B, an electrode 4B, a first bus bar 5B, and a second bus bar 6B are provided.
  • the first IDT electrode including the plurality of electrodes 3A, the electrodes 4A and the first bus bar 5A, and the second bus bar 6A is the electrode 3, the electrode 4, the first bus bar 5, and the second bus bar 6 of the first embodiment. It has the same configuration as.
  • the plurality of electrodes 3B are connected to the first bus bar 5B.
  • the plurality of electrodes 4B are connected to the second bus bar 6B.
  • the first bus bar 5B is electrically connected to the third terminal 12c and the third bump 14c via the third wiring 13c.
  • the second bus bar 6B is electrically connected to the second bump 14b and the second bus bar 6A of the first IDT electrode via the second wiring 13b.
  • the support member 8 has an opening 8a in a region overlapping the electrodes 3A and 4A. As a result, the cavity 9A is formed.
  • the support member 8 has an opening 8b in a region overlapping the electrodes 3B and 4B. As a result, the hollow portion 9B is formed.
  • the cover member 22 covers the support member 8 and the plurality of cavity portions 9A and 9B. Even if the support member 8 is provided with a plurality of cavities 9A and 9B, the pressure applied to the cavities 9A and 9B and the voids on the first main surface 2a side of the piezoelectric layer 2 (the first of the piezoelectric layers 2). The difference between the pressure applied to the space formed between the main surface 2a and the mounting substrate 30) is reduced, and damage to the structures around the cavities 9A and 9B can be suppressed.
  • FIG. 17 is a plan view showing an elastic wave element included in the elastic wave device of the second embodiment.
  • FIG. 18 is a cross-sectional view of a portion of FIG. 17 along the line XVIII-XVIII.
  • a configuration in which a through hole 10 penetrating at least a part of the support member 8 and the piezoelectric layer 2 is provided in a region different from the cavity portion 9 will be described.
  • the through hole 10 and the cavity 9 are arranged side by side in a direction orthogonal to the length direction of the electrodes 3 and 4.
  • One end side of the groove portion 8g provided in the support member 8 is connected to the through hole 10, and the other end side of the groove portion 8g is connected to the cavity portion 9.
  • the through hole 10 and the cavity 9 are connected by the groove 8g provided in the support member 8.
  • the through hole 10 is provided so as to penetrate the support member 8 and the intermediate layer 7 in the thickness direction, and is continuous with the recess formed on the second main surface 2b side of the piezoelectric layer 2. ..
  • the through hole 10 may be provided so as to penetrate the piezoelectric layer 2 in the thickness direction.
  • the through hole 10 of the support member 8 and the intermediate layer 7 is provided in a region different from the cavity portion 9, that is, a region that does not overlap with the electrode 3 and the electrode 4. Further, the groove portion 8g is provided on the surface of the support member 8 facing the cover member 22.
  • the cover member 22 is provided so as to cover the support member 8, the cavity portion 9, the groove portion 8 g, and the through hole 10.
  • the bottom surface of the groove portion 8g is provided apart from the cover member 22, and the cavity portion 9 and the through hole 10 are spatially connected via the groove portion 8g.
  • FIG. 19 is a cross-sectional view showing an elastic wave element included in the elastic wave device according to the third modification of the second embodiment.
  • the elastic wave device 1D elastic wave element 20D
  • a configuration in which a through hole 10A penetrating the piezoelectric layer 2 is provided in a region overlapping the cavity portion 9 will be described.
  • the through hole 10A is provided so as to penetrate from the first main surface 2a to the second main surface 2b of the piezoelectric layer 2. Be done.
  • the through hole 10A is provided in a region that overlaps with the cavity 9 and a region that does not overlap with the electrode 3 and the electrode 4.
  • the gap provided on the first main surface 2a side of the piezoelectric layer 2 and the cavity 9 provided on the second main surface 2b side of the piezoelectric layer 2 are connected via the through hole 10A. .. Therefore, the elastic wave device 1D according to the third modification can suppress the difference between the pressure applied to the cavity 9 and the pressure applied to the void provided on the first main surface 2a side of the piezoelectric layer 2. ..
  • Two through holes 10A are provided in the region overlapping the cavity portion 9, and the electrodes 3 and 4 are arranged between the two through holes 10A.
  • the number and arrangement of the through holes 10A are merely examples and can be changed as appropriate.
  • the number of through holes 10A may be one or three or more.
  • the third modification may be combined with the second embodiment described above, in which the through hole 10 is provided in a region different from the cavity portion 9 and the through hole penetrates the piezoelectric layer 2 in the region overlapping the cavity portion 9. 10A may be provided.
  • FIG. 20 is an explanatory diagram for explaining a method of manufacturing the elastic wave device of the second embodiment.
  • steps ST1 and ST2 of the elastic wave element forming steps are the same as those in FIG. 14, and the repeated description will be omitted.
  • an opening 2d is formed in the piezoelectric layer 2 of the elastic wave element 20C (step ST21).
  • the opening 2d in the piezoelectric layer 2 is a region overlapping the dicing line that divides the elastic wave element 20C into individual pieces, and a step of forming slits 2c and 7c in the piezoelectric layer 2 and the intermediate layer 7 (see FIG. 14, step ST3). It will be done at the same time.
  • the opening 2d is formed so as to penetrate from the first main surface 2a to the second main surface 2b side at a position different from the region where the cavity 9 is to be formed. Further, the opening 2d of the piezoelectric layer 2 is formed by, for example, dry etching in the same process as the slit 2c.
  • a groove portion 8g is formed on the back surface side of the support member 8 (the surface of the support member 8 opposite to the surface facing the piezoelectric layer 2) (step ST22).
  • One end side of the groove portion 8g is provided in a region overlapping with at least a part of the opening 2d, and the other end side of the groove portion 8g is provided in a region overlapping with at least a region where the cavity portion 9 is to be formed.
  • the groove portion 8g is formed by, for example, dry etching or the like.
  • a cavity 9 and a through hole 10 penetrating the support member 8 and the intermediate layer 7 are formed (step ST23).
  • the through hole 10 is formed in the same process as the cavity 9 by, for example, etching.
  • the membrane structure of the piezoelectric layer 2 is formed in the cavity 9, and the through hole 10 is formed by being connected to the opening 2d of the piezoelectric layer 2.
  • the through hole 10 is formed in a region different from the cavity 9 in the elastic wave device 1C (elastic wave element 20C) of the second embodiment.
  • the steps after step ST23 are the same as those of steps ST5 to ST9 (see FIG. 14) described above, and the description of repetition will be omitted.
  • the method for manufacturing the elastic wave device 1C (elastic wave element 20C) of the second embodiment can be applied to the third modification of the second embodiment described above.
  • FIG. 21 is a plan view showing an elastic wave element included in the elastic wave device of the third embodiment.
  • FIG. 22 is a cross-sectional view of a portion of FIG. 21 along the line XXII-XXII.
  • the cavity 9 and the support member are formed on the upper surface of the support member 8 (the surface of the support member 8 opposite to the surface facing the piezoelectric layer 2). Grooves 8h and 8i connecting the side surfaces 8d and 8e of 8 are provided.
  • the side surface 8d of the support member 8 is provided on one of the directions orthogonal to the length direction of the electrode 3 and the electrode 4, and the side surface 8e of the support member 8 is the electrode 3 and the electrode 4. It is provided on the other side in the direction orthogonal to the length direction of the above, that is, on the opposite side of the side surface 8d.
  • the groove portion 8h extends in a direction orthogonal to the length direction of the electrodes 3 and 4. One end side of the groove portion 8h is connected to the side surface 8d of the support member 8, and the other end side of the groove portion 8h is connected to the cavity portion 9. Similarly, the groove portion 8i extends in a direction orthogonal to the length direction of the electrodes 3 and 4. One end side of the groove portion 8i is connected to the cavity portion 9, and the other end side of the groove portion 8i is connected to the side surface 8e of the support member 8.
  • groove portions 8h and 8i By providing the groove portions 8h and 8i in this way, a gap is formed between the support member 8 and the cover member 22, so that the pressure applied to the cavity portion 9 in the manufacturing process can be reduced. It should be noted that at least one of the groove portions 8h and 8i may be provided, or three or more groove portions may be provided.
  • FIG. 23 is a plan view showing an elastic wave element included in the elastic wave device according to the fourth modification of the third embodiment.
  • the elastic wave device 1F elastic wave element 20F
  • a plurality of cavity portions 9A and 9B are provided in the support member 8, and the upper surface of the support member 8 (piezoelectric layer of the support member 8) is provided.
  • a configuration will be described in which a connection groove portion 8j for connecting a plurality of cavity portions 9A and 9B is provided on the surface facing the surface 2 and the surface opposite to the surface).
  • the piezoelectric layer 2 is provided with an IDT electrode composed of a plurality of electrodes 3A, electrodes 4A, a first bus bar 5A, and a second bus bar 6A.
  • the piezoelectric layer 2 is provided with an IDT electrode composed of a plurality of electrodes 3B, an electrode 4B, a first bus bar 5B, and a second bus bar 6B.
  • the configurations of each of these IDT electrodes and the cavities 9A and 9B are the same as those of the second modification (FIG. 16) of the first embodiment described above, and the repeated description will be omitted.
  • connection groove portion 8j is provided between the cavity portion 9A and the cavity portion 9B.
  • One end side of the connection groove 8j is connected to the cavity 9B, and the other end of the connection groove 8j is connected to the cavity 9A.
  • the plurality of cavity portions 9A and 9B are connected by the connection groove portion 8j.
  • Grooves 8k and 8l are further provided on the upper surface of the support member 8 (the surface of the support member 8 opposite to the surface facing the piezoelectric layer 2).
  • the groove portion 8k extends in a direction orthogonal to the length direction of the electrodes 3A and 4A.
  • One end side of the groove portion 8k is connected to the cavity portion 9A, and the other end side of the groove portion 8k is connected to the side surface 8e of the support member 8.
  • the groove portion 8l extends in a direction orthogonal to the length direction of the electrodes 3B and 4B.
  • One end side of the groove portion 8l is connected to the side surface 8d of the support member 8, and the other end side of the groove portion 8l is connected to the cavity portion 9B.
  • FIG. 24 is a cross-sectional view showing an elastic wave device according to a fifth modification of the third embodiment.
  • the cover member 22G is composed of a sealing member made of metal.
  • the elastic wave element 20G of the fifth modification is provided with groove portions 8h and 8i in the support member 8 as in the elastic wave element 20E of the third embodiment described above.
  • the present invention is not limited to this, and the cover member 22G of the fifth modification can be applied to each of the above-described embodiments and modifications.
  • the cover member 22G includes a solder 24 and a metal layer 25.
  • the solder 24 is provided so as to cover the hollow portion 9 and the groove portions 8h and 8i of the support member 8 and to cover the side surfaces of the support member 8 and the piezoelectric layer 2. Further, the solder 24 is connected to the frame-shaped electrode 32d of the mounting substrate 30.
  • the metal layer 25 covers the solder 24 and is provided integrally with the solder 24. For example, nickel (Ni) is used for the metal layer 25, and the metal layer 25 is formed by plating.
  • FIG. 25 is an explanatory diagram for explaining a method of manufacturing an elastic wave device according to a sixth modification of the third embodiment.
  • FIG. 26 is a plan view for explaining a method of manufacturing an elastic wave device according to a sixth modification of the third embodiment. Note that FIG. 26 shows a plan view of steps ST31 and ST32 among steps ST31 to ST34 shown in FIG. 25. Further, in the method for manufacturing the elastic wave device 1H (elastic wave element 20H) according to the sixth modification of the third embodiment, steps ST1 to ST3 of the elastic wave element forming steps are the same as those in FIG. 14, and are repeated. The explanation is omitted.
  • a groove portion 8m and a groove portion 8n are formed on the surface of the support member 8 opposite to the surface facing the piezoelectric layer 2 (step ST31). ..
  • the groove portion 8m extends in a direction orthogonal to the length direction of the electrodes 3 and 4.
  • the groove portion 8n extends in the length direction of the electrode 3 and the electrode 4, and is orthogonal to the groove portion 8m.
  • the groove portion 8m and the groove portion 8n are formed by, for example, etching or the like.
  • step ST32 the cavity 9 penetrating the support member 8 and the intermediate layer 7 is formed (step ST32).
  • the support member 8 and the intermediate layer 7 are removed by etching or the like to form openings 7a and 8a.
  • the membrane structure of the piezoelectric layer 2 is formed in the region overlapping the electrodes 3 and 4.
  • the bump 14 is formed on the terminal 12 (step ST33).
  • the bump 14 is configured to include, for example, gold (Au) or a gold alloy.
  • a slit 8c is formed in the support member 8 in a region overlapping the dicing line, and the elastic wave element 20 is divided into individual pieces (step ST34).
  • the slit 8c is provided so as to intersect the groove portion 8m or the groove portion 8n formed in step ST31.
  • the groove portion 8m and the groove portion 8n are formed in the support member 8 in the elastic wave element 20H according to the sixth modification of the third embodiment.
  • the steps after step ST34 are the same as those of steps ST7 to ST9 (see FIG. 14) described above, and the description of repetition will be omitted.
  • the method for manufacturing the elastic wave device 1H (elastic wave element 20H) according to the sixth modification of the third embodiment is described in the fourth modification and the fifth modification of the third embodiment and the third embodiment described above. Can also be applied.

Landscapes

  • Physics & Mathematics (AREA)
  • Acoustics & Sound (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Surface Acoustic Wave Elements And Circuit Networks Thereof (AREA)

Abstract

La présente invention concerne un dispositif à ondes élastiques qui comprend un substrat de montage ayant un câblage, un élément d'onde élastique monté sur le substrat de montage, et un élément de couvercle recouvrant l'élément d'onde élastique, où : l'élément d'onde élastique comprend une couche piézoélectrique ayant une première surface principale et une deuxième surface principale opposée à la première surface principale, une électrode disposée sur la première surface principale de la couche piézoélectrique, et un substrat de support stratifié sur la deuxième surface principale de la couche piézoélectrique ; la première surface principale de la couche piézoélectrique est disposée de manière à faire face au substrat de montage ; une partie de cavité pénétrant dans le substrat de support est disposée sur une partie du substrat de support ; dans une vue en plan à partir de la première surface principale, au moins une partie de l'électrode est disposée de manière à chevaucher la partie de cavité ; et l'élément de couvercle recouvre la partie de cavité du substrat de support, et est relié au substrat de montage de manière à recouvrir les surfaces latérales de la couche piézoélectrique et du substrat de support.
PCT/JP2021/037964 2020-10-14 2021-10-13 Dispositif à ondes élastiques et son procédé de fabrication WO2022080433A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US202063091337P 2020-10-14 2020-10-14
US63/091,337 2020-10-14

Publications (1)

Publication Number Publication Date
WO2022080433A1 true WO2022080433A1 (fr) 2022-04-21

Family

ID=81209259

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2021/037964 WO2022080433A1 (fr) 2020-10-14 2021-10-13 Dispositif à ondes élastiques et son procédé de fabrication

Country Status (1)

Country Link
WO (1) WO2022080433A1 (fr)

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6068710A (ja) * 1983-09-26 1985-04-19 Toshiba Corp 圧電薄膜共振子
JP2005304021A (ja) * 2004-04-06 2005-10-27 Samsung Electronics Co Ltd バルク音響波共振器、フィルタ、デュプレクサ及びその製造方法
JP2010233210A (ja) * 2009-03-03 2010-10-14 Nippon Dempa Kogyo Co Ltd 弾性波デバイス及び電子部品
JP2013528996A (ja) * 2010-04-23 2013-07-11 テクノロジアン テュトキムスケスクス ヴェーテーテー 広帯域音響結合薄膜ｂａｗフィルタ
JP2013214954A (ja) * 2012-03-07 2013-10-17 Taiyo Yuden Co Ltd 共振子、周波数フィルタ、デュプレクサ、電子機器及び共振子の製造方法
JP2016086308A (ja) * 2014-10-27 2016-05-19 株式会社村田製作所 圧電共振器、及び圧電共振器の製造方法
WO2018110464A1 (fr) * 2016-12-15 2018-06-21 株式会社村田製作所 Dispositif à ondes élastiques
US20200321939A1 (en) * 2019-04-05 2020-10-08 Resonant Inc. Transversely-excited film bulk acoustic resonator package and method

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6068710A (ja) * 1983-09-26 1985-04-19 Toshiba Corp 圧電薄膜共振子
JP2005304021A (ja) * 2004-04-06 2005-10-27 Samsung Electronics Co Ltd バルク音響波共振器、フィルタ、デュプレクサ及びその製造方法
JP2010233210A (ja) * 2009-03-03 2010-10-14 Nippon Dempa Kogyo Co Ltd 弾性波デバイス及び電子部品
JP2013528996A (ja) * 2010-04-23 2013-07-11 テクノロジアン テュトキムスケスクス ヴェーテーテー 広帯域音響結合薄膜ｂａｗフィルタ
JP2013214954A (ja) * 2012-03-07 2013-10-17 Taiyo Yuden Co Ltd 共振子、周波数フィルタ、デュプレクサ、電子機器及び共振子の製造方法
JP2016086308A (ja) * 2014-10-27 2016-05-19 株式会社村田製作所 圧電共振器、及び圧電共振器の製造方法
WO2018110464A1 (fr) * 2016-12-15 2018-06-21 株式会社村田製作所 Dispositif à ondes élastiques
US20200321939A1 (en) * 2019-04-05 2020-10-08 Resonant Inc. Transversely-excited film bulk acoustic resonator package and method

Similar Documents

Publication Publication Date Title
WO2022085581A1 (fr) Dispositif à ondes acoustiques
WO2023085362A1 (fr) Dispositif à ondes élastiques
WO2022131309A1 (fr) Dispositif à ondes élastiques
WO2022080433A1 (fr) Dispositif à ondes élastiques et son procédé de fabrication
WO2022211097A1 (fr) Dispositif à ondes élastiques et son procédé de fabrication
WO2023195513A1 (fr) Dispositif à ondes élastiques et son procédé de fabrication
WO2022210683A1 (fr) Dispositif à ondes élastiques et son procédé de fabrication
US20240048114A1 (en) Acoustic wave device and manufacturing method for acoustic wave device
WO2022209525A1 (fr) Dispositif à ondes élastiques
WO2023013694A1 (fr) Appareil à ondes élastiques et procédé de fabrication d'un appareil à ondes élastiques
WO2024029609A1 (fr) Dispositif à ondes élastiques
US20240014796A1 (en) Acoustic wave device
US20240014799A1 (en) Acoustic wave device
WO2023085368A1 (fr) Dispositif à ondes élastiques
US20240113684A1 (en) Acoustic wave device
WO2023058727A1 (fr) Dispositif à ondes élastiques et son procédé de fabrication
US20240030885A1 (en) Acoustic wave device
WO2023058713A1 (fr) Procédé de fabrication d'un élément à ondes élastiques et élément à ondes élastiques
WO2023090460A1 (fr) Procédé de fabrication d'un dispositif à ondes acoustiques
US20240048115A1 (en) Acoustic wave device and method of manufacturing acoustic wave device
WO2023195409A1 (fr) Dispositif à ondes élastiques et procédé de production de dispositif à ondes élastiques
US20240186979A1 (en) Acoustic wave device and method of manufacturing acoustic wave device
WO2023140270A1 (fr) Procédé de fabrication d'un élément à ondes élastiques et élément à ondes élastiques
WO2023058728A1 (fr) Dispositif à ondes élastiques et son procédé de fabrication
US20230361749A1 (en) Acoustic wave device and method for manufacturing acoustic wave device

Legal Events

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

Ref document number: 21880170

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 21880170

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: JP