JP2022179861A - Acoustic wave device and module having the acoustic wave device - Google Patents

Abstract

To provide an acoustic wave device and a module which can prevent a sealing resin from entering to an electrode without obstruction or while reducing obstruction.SOLUTION: An acoustic wave device includes a wiring board, a device chip which is provided on the wiring board and is electrically connected to the wiring board, and a sealing resin for sealing the device chip while remaining a space between the wiring board and the device chip, wherein the device chip has a wiring pattern, a plurality of electrodes periodically formed in a wiring region that is a region provided with the wiring pattern, and a liquid entry prevention pattern which is provided at a position closer to the outer edge of the wiring region than the plurality of electrodes out of the wiring region so as to project from the wiring pattern, on the main surface opposite to the wiring board.SELECTED DRAWING: Figure 2

Description

The present disclosure relates to acoustic wave devices and modules comprising the acoustic wave devices.

Patent Literature 1 discloses an acoustic wave device. The acoustic wave device is provided with a dam that forms a hollow portion between the acoustic wave device and the substrate and prevents the sealing resin from entering the hollow portion from the outside.

JP 2020-102713 A

By forming the dam so as to surround the IDT (Interdigital Transducer) electrode and the connecting portion in plan view, it is possible to suppress the sealing resin from entering the electrode arrangement portion of the acoustic wave device. However, the dam is a large pattern, and the formation of the dam reduces the design area and increases the size of the device. Also, if the dam is a metal pattern, the coupling will affect the characteristics of the device. Furthermore, the dam formed along the outer edge of the device chip requires a certain height in order to prevent the encapsulation resin from entering, so it is not easy to manufacture.

The present disclosure has been made to solve the above problems. An object of the present disclosure is to provide an acoustic wave device and a module including the acoustic wave device that suppress penetration of the sealing resin into the electrodes without or with reduced harm.

The acoustic wave device according to the present disclosure is
a wiring board;
a device chip provided on the wiring substrate and electrically connected to the wiring substrate;
A sealing resin that seals the device chip while leaving a space between the wiring board and the device chip,
The device chip has, on a main surface facing the wiring substrate,
wiring pattern,
a plurality of electrodes periodically formed in a wiring region, which is a region in which the wiring pattern is provided;
a liquid intrusion prevention pattern provided protruding from the wiring pattern in a position closer to an outer edge of the wiring region than the plurality of electrodes in the wiring region.

The plurality of electrodes has a resonator that excites a surface acoustic wave and a reflector adjacent to the resonator, and the liquid penetration prevention pattern extends in an orthogonal direction orthogonal to the propagation direction of the surface acoustic wave. The non-parallel arrangement is one aspect of the present disclosure.

The wiring pattern has a bump pad and a wiring portion electrically connecting the bump pad to the plurality of electrodes, and the liquid penetration prevention pattern is provided so as to protrude from the wiring portion. It is considered a form of disclosure.

The wiring pattern has a bump pad and a wiring portion electrically connecting the bump pad to the plurality of electrodes, and the liquid penetration prevention pattern is provided so as to protrude from the bump pad. It is considered a form of disclosure.

An aspect of the present disclosure is that the liquid intrusion prevention pattern has a first portion extending substantially perpendicularly from the wiring pattern and a second portion extending from the tip of the first portion in the outer edge direction of the device chip. It is said that

The liquid intrusion prevention pattern has a first portion extending substantially perpendicularly from the wiring pattern and a second portion extending from a tip of the first portion in an outer edge direction of the device chip. It is an aspect of the present disclosure that the first portion is on a line perpendicular to the direction of propagation of surface acoustic waves passing through the region between the devices.

It is an aspect of the present disclosure that the liquid entry prevention pattern has a curved shape.

It is an aspect of the present disclosure that a plurality of liquid intrusion prevention patterns are formed on one side of the wiring pattern.

An aspect of the present disclosure is that the liquid intrusion prevention pattern is provided only on a side of the wiring pattern that is substantially perpendicular to the surface acoustic wave propagation direction of the plurality of electrodes.

An aspect of the present disclosure is that the liquid intrusion prevention pattern is formed thinner than the wiring pattern.

An aspect of the present disclosure is that the device chip has a substrate in which a piezoelectric substrate and a substrate made of sapphire, silicon, alumina, spinel, crystal, or glass are bonded together.

It is an aspect of the present disclosure that the sealing resin is a thermosetting resin.

An embodiment of the present disclosure includes a second device chip formed with a bandpass filter having a plurality of surface acoustic wave resonators.

One aspect of the present disclosure is to include a second device chip formed with a bandpass filter having a plurality of thin film acoustic resonators.

A module including the acoustic wave device described above is one aspect of the present disclosure.

According to the present disclosure, it is possible to suppress penetration of the sealing resin into the electrodes without or with reduced harm.

1 is a cross-sectional view of an acoustic wave device according to Embodiment 1; FIG. 2 is a diagram showing the main surface of the device chip in Embodiment 1; FIG. 2 is a partially enlarged view of the device chip in Embodiment 1. FIG. 4A and 4B are diagrams showing an example of a sealing resin according to Embodiment 1; FIG. 3A and 3B are diagrams showing an example of a wiring pattern and a plurality of electrodes according to the first embodiment; FIG. It is a figure which shows the penetration|invasion of the sealing resin which concerns on a comparative example. FIG. 11 is a partially enlarged view of a device chip in Embodiment 2; FIG. 11 is a partially enlarged view of a device chip in Embodiment 3; FIG. 11 is a partially enlarged view of a device chip in Embodiment 4; FIG. 11 is a partially enlarged view of a device chip in Embodiment 5;

Embodiments will be described with reference to the accompanying drawings. In addition, the same code|symbol is attached|subjected to the part which is the same or corresponds in each figure. Redundant description of the relevant part will be simplified or omitted as appropriate.

Embodiment 1.
FIG. 1 is a cross-sectional view of an acoustic wave device according to Embodiment 1. FIG. The acoustic wave device 1 has a wiring board 2 . According to one example, the wiring board 2 is a multilayer board containing resin. According to another example, the wiring substrate 2 is a Low Temperature Co-fired Ceramics (LTCC) multilayer substrate consisting of multiple dielectric layers. A passive element such as a capacitor or an inductor may be formed inside the wiring board 2 .

In the example of FIG. 1, the wiring board 2 has a plurality of conductive pads 2b on its upper surface, which is the component mounting surface. The lower surface of the wiring board 2 is a mounting surface to a mother board, for example. A plurality of conductive pads 2c are provided on the lower surface of the wiring board 2. As shown in FIG. Corresponding conductive pads 2b and conductive pads 2c are connected to each other by internal conductors 2a or via-hole conductors.

A device chip 3 electrically connected to the wiring board 2 is placed on the wiring board 2 . The device chip 3 is a surface acoustic wave device chip. The device chip 3 has a piezoelectric substrate 3a made of a piezoelectric material. According to one example, the piezoelectric substrate 3a is a substrate made of a piezoelectric single crystal such as lithium tantalate, lithium niobate or quartz. According to another example, the piezoelectric substrate 3a is a substrate made of piezoelectric ceramics. According to yet another example, the piezoelectric substrate 3a is a substrate in which a piezoelectric substrate and a support substrate are bonded together. The support substrate is, for example, a substrate made of sapphire, silicon, alumina, spinel, quartz or glass.

According to one example, the piezoelectric substrate 3a is the substrate on which the functional elements are formed. For example, a reception filter and a transmission filter are formed on the main surface (lower surface) of the device chip 3 that faces the wiring substrate 2 .

The receive filter is formed so that an electrical signal in a desired frequency band can pass. For example, the receive filter is a ladder-type filter consisting of a plurality of series resonators and a plurality of parallel resonators.

The transmission filter is formed so that an electrical signal in a desired frequency band can pass. For example, the transmission filter is a ladder-type filter consisting of multiple series resonators and multiple parallel resonators.

FIG. 1 shows an example in which a wiring pattern 3b and a plurality of periodically formed electrodes 3c are formed on the main surface of a device chip 3. As shown in FIG. According to one example, the plurality of electrodes 3c are IDT electrodes that are comb-shaped electrode fingers. A high-frequency electric field is applied to the IDT electrode from the lead terminal on the power supply side to excite surface acoustic waves, and the surface acoustic waves are converted into high-frequency electric fields by piezoelectric action, thereby obtaining filter characteristics.

The wiring pattern 3 b and the conductive pad 2 b are electrically connected by bumps 4 . The bumps 4 are for example Au, conductive glue or solder.

The acoustic wave device 1 has a sealing resin 5 . The sealing resin 5 seals the device chip 3 while leaving a space 6 between the wiring board 2 and the device chip 3 . According to one example, the device chip 3 is mounted on the wiring substrate 2 and then a resin sheet is placed on the device chip so as to straddle the device chip 3 . According to one example, the resin sheet is a liquid epoxy resin formed into a sheet. According to another example, the resin sheet can be a synthetic resin, such as polyimide, which is different than an epoxy resin. A protective film made of polyethylene terephthalate (PET) can be provided on the upper surface of the resin sheet, and a base film made of polyester can be provided on the lower surface of the resin sheet.

By placing the resin sheet on the device chip 3 , the resin sheet is temporarily fixed to the device chip 3 . Then, the structure including the device chip 3, the resin sheet, and the wiring board 2 is passed between an upper roller and a lower roller heated to at least the softening temperature of the resin sheet, so that the side surfaces of the device chip 3 and the wiring board 2 are separated from each other by the resin sheet. 2 is filled on top. This is called hot roller lamination. Any method other than the heat roller lamination method may be employed as long as it can perform lamination as shown in FIG.

After that, the process proceeds to a press forming step in order to fully cure the resin sheet. For example, by pressing the resin sheet in the direction of the wiring board 2 with a press having an upper mold and a lower mold heated to the curing temperature of the resin, expansion of the air in the space 6 is suppressed and the resin is compressed. Harden.

According to this example, the resin sheet is once heated up to the softening temperature and then pressurized and deformed so as to adhere to the outer surface of the device chip 3 and the upper surface of the wiring board 2, and then heated up to the curing temperature to shape it. is fixed, the sealing resin 5 is formed. The sealing resin 5 , for example, makes the space 6 an airtight space and reinforces the fixing force of the device chip 3 to the wiring board 2 . In the example of FIG. 1 , the space 6 is an airtight space surrounded by the main surface of the device chip 3 , the upper surface of the wiring board 2 and the sealing resin 5 . The number of device chips mounted on the wiring board 2 can be two or more. According to one example, the sealing resin 5 is a thermosetting resin.

FIG. 2 is a diagram showing a configuration example of the main surface of the device chip 3. As shown in FIG. In this example, the device chip 3 has wiring patterns 3b and 3d on its main surface. The wiring pattern is made of an appropriate metal or alloy such as silver, aluminum, copper, titanium, palladium. According to another example, the wiring pattern is formed by a laminated metal film formed by laminating a plurality of metal layers. For example, the wiring pattern has a thickness of 150 nm to 400 nm.

A region provided with a wiring pattern constitutes a wiring region. In FIG. 2, the wiring area 10 is a rectangular area surrounded by dashed lines. A wiring pattern is formed in this wiring region 10 and is not formed outside the wiring region 10 . A plurality of electrodes 3 c are periodically formed in the wiring region 10 . A plurality of electrodes 3c provide a surface acoustic wave filter (SAW filter). The plurality of electrodes 3c constitute, for example, a transversal SAW filter or a SAW resonator filter having reflectors.

In the example of FIG. 2, the wiring pattern 3b is a bump pad, and the wiring pattern 3d is a wiring portion that electrically connects the bump pad to a plurality of electrodes 3c. The shape and distribution of the wiring pattern can be arbitrarily modified according to the design.

Liquid penetration prevention patterns 6 and 7 are provided in the wiring region 10 so as to protrude from the wiring pattern. The liquid intrusion prevention patterns 6 and 7 are provided at positions closer to the outer edge of the wiring region 10 than the plurality of electrodes 3c. The liquid intrusion prevention pattern prevents or suppresses the liquid component of the sealing resin from reaching the plurality of electrodes 3 c when the liquid component enters the wiring region 10 . Therefore, the liquid penetration prevention pattern is between the outer edge of the wiring region 10 and the plurality of electrodes 3c. In the example of FIG. 2, the liquid intrusion prevention pattern 6 is provided so as to protrude from the wiring pattern 3d (wiring portion), and prevents the liquid component intruding into the wiring region 10 from the left side in the figure from reaching the plurality of electrodes 3c. prevent. The liquid intrusion prevention pattern 7 is provided so as to protrude from the wiring pattern 3b (bump pad), and prevents the liquid component entering the wiring region 10 from the upper side in the drawing from reaching the plurality of electrodes 3c. The layout of the wiring pattern, the plurality of electrodes, and the liquid penetration prevention pattern in FIG. 2 is an example, and arbitrary modifications are possible.

FIG. 3 is a diagram showing an example of the shape of the liquid intrusion prevention pattern. The plurality of electrodes 3c has a resonator 31 that excites surface acoustic waves and a reflector 32 adjacent to the resonator. The direction of propagation of surface acoustic waves is the y-direction. The liquid intrusion prevention pattern 6 has a first portion 6A extending substantially perpendicularly from the wiring pattern 3d and a second portion 6B extending from the tip of the first portion 6A toward the outer edge of the device chip. As a result, when the liquid component of the sealing resin 5 enters the wiring region 10 along the wiring pattern 3d from the x-negative direction, the liquid component is blocked by the first portion 6A and the second portion 6B. can be prevented from reaching the plurality of electrodes 3c. Here, the propagation direction of surface acoustic waves is the y direction. Therefore, the first portion 6A is provided non-parallel to the x-direction, which is an orthogonal direction orthogonal to the y-direction. If the first portion is provided parallel to the x-direction, it does not contribute to damming the liquid component. Therefore, the first portion needs to be provided non-parallel to the x-direction.

In the example of FIG. 3, the first portion 6A is on a line orthogonal to the propagation direction of surface acoustic waves passing through the region between the resonator 31 and the reflector 32. In the example of FIG. This can prevent liquid components from entering between the resonator 31 and the reflector 32 .

FIG. 4 is a diagram showing an example in which the sealing resin has entered the wiring region 10. As shown in FIG. In this example, the liquid component 5b of the sealing resin penetrates into the wiring region 10 along the steps of the wiring pattern 3d, that is, along the side surfaces of the wiring pattern 3d. If the liquid entry prevention pattern 6 were not present, the liquid component 5b could reach the plurality of electrodes 3c and enter the space of the IDT. However, in the acoustic wave device according to Embodiment 1, the liquid penetration prevention pattern 6 blocks the liquid component 5b and prevents the liquid component 5b from reaching the plurality of electrodes 3c.

Furthermore, the liquid intrusion prevention pattern 7 shown in FIG. 2 dams up the liquid component that has entered the wiring region 10 along the wiring pattern 3b, thereby preventing the liquid component from reaching the plurality of electrodes 3c.

In the examples of FIGS. 2 and 3, the liquid entry prevention pattern has a curved shape in plan view. As a result, even if a considerable amount of liquid component enters the wiring area 10, the liquid component can be blocked by the liquid intrusion prevention pattern. In the examples of FIGS. 2 and 3, the liquid entry prevention pattern 6 has the first portion 6A and the second portion 6B, but the second portion may be omitted. In other words, the liquid penetration prevention pattern may have a linear shape.

According to one example, the liquid penetration prevention pattern can be formed thinner than the wiring pattern. Narrowing the liquid intrusion prevention pattern increases the degree of freedom in design. Thus, the anti-liquid penetration pattern can be provided near the IDT, for example. Further, by making the liquid intrusion prevention pattern smaller, it is possible to reduce the influence of the liquid intrusion prevention pattern on the characteristics of the acoustic wave device.

The liquid penetration prevention pattern can be formed in the same process as the wiring pattern. Forming the wiring pattern and the liquid penetration prevention pattern in the same process enables simplification of the process. According to another example, the anti-liquid entry pattern can be formed of the same material as the electrodes 3c and simultaneously with the electrodes 3c. In this case, the IDT and the liquid penetration prevention pattern are made of the same material. According to yet another example, the liquid intrusion prevention pattern can be formed of an insulator. In this case, the influence of the liquid intrusion prevention pattern on the characteristics of the acoustic wave device can be eliminated or reduced.

According to one example, the liquid intrusion prevention pattern can be provided only on a side of the wiring pattern that is substantially perpendicular to the propagation direction of the surface acoustic waves of the plurality of electrodes. That is, in the example of FIG. 4, the liquid intrusion prevention pattern can be provided only on the sides of the wiring pattern that are parallel or substantially parallel to the x-axis that is perpendicular to the y-direction, which is the propagation direction of the surface acoustic waves. When the liquid component advances in the x-positive direction or the x-negative direction from the left or right side of FIG. 4 and enters the wiring area, the liquid component easily reaches between a plurality of electrodes and adversely affects the device chip. big. Therefore, in this case, it is effective to provide the liquid penetration prevention pattern on the side of the wiring pattern that is substantially parallel to the x-axis.

FIG. 5 is a diagram showing a layout example of wiring patterns. The wiring pattern is the white portion. In order to provide a liquid penetration prevention pattern in such a complicated wiring pattern, it is necessary to make the liquid penetration prevention pattern smaller. A liquid entry prevention pattern can be provided at an arbitrary position in FIG. 5 to prevent liquid components from reaching a plurality of electrodes.

FIG. 6 is a partially enlarged view of an acoustic wave device according to a comparative example. In this comparative example, since there is no liquid intrusion prevention pattern, the liquid component 5b of the sealing resin intrudes into the wiring area along the wiring pattern 3d and reaches the space of the IDT.

Embodiment 2.
FIG. 7 is a diagram showing a configuration example of the main surface of the device chip according to the second embodiment. A resonator 31 and a reflector 32 are in contact with the wiring pattern 3d. The liquid entry prevention pattern 6 prevents liquid components from reaching the reflector 32 .

Embodiment 3.
FIG. 8 is a diagram showing a configuration example of the main surface of the device chip according to the third embodiment. A liquid penetration prevention pattern 6 is connected to the upper wiring pattern 3d, and a liquid penetration prevention pattern 8 is connected to the lower wiring pattern 3d. As a result, it is possible to prevent the liquid component from proceeding in the positive x direction from the left side of the drawing.

Embodiment 4.
FIG. 9 is a diagram showing a configuration example of the main surface of the device chip according to the fourth embodiment. The liquid intrusion prevention pattern 6 has only a straight first portion 6A without a bent portion. In this case, a simple pattern can increase the degree of design freedom.

Embodiment 5.
FIG. 10 is a diagram showing a configuration example of the main surface of the device chip according to the fifth embodiment. Two liquid intrusion prevention patterns 6 are formed on one side of the wiring pattern 3d. The two liquid penetration prevention patterns 6 can reliably suppress the penetration of liquid components. Three or more liquid penetration prevention patterns can be provided on one side of the wiring pattern.

Although one device chip has been described in the embodiments so far, according to another example, it is possible to provide an acoustic wave device in which a plurality of device chips are sealed with a sealing resin. For example, an acoustic wave device can include a second device chip formed with a bandpass filter having a plurality of surface acoustic wave resonators. According to yet another example, an acoustic wave device can comprise a second device chip formed with a bandpass filter having a plurality of thin film acoustic resonators. According to yet another example, an acoustic wave device can include a ladder-type filter further comprising a plurality of parallel resonators.

A module can be provided comprising any one of the acoustic wave devices described above. A module may include a wiring substrate, an integrated circuit component IC, an acoustic wave device, an inductor, and an encapsulation. According to one example, the integrated circuit component IC is mounted inside the wiring substrate. An integrated circuit component IC includes a switching circuit and a low noise amplifier. An acoustic wave device is mounted on the main surface of the wiring board. An inductor is also mounted on the main surface of the wiring board. Inductors are implemented for impedance matching. For example, the inductor is an Integrated Passive Device (IPD). The sealing portion seals a plurality of electronic components including acoustic wave devices.

Having described several aspects of at least one embodiment, it is to be appreciated various alterations, modifications, and improvements will readily occur to those skilled in the art. Such alterations, modifications, and improvements are intended to be part of this disclosure, and are intended to be within the scope of this disclosure.

It is to be understood that the method and apparatus embodiments described herein are not limited in application to the details of construction and arrangement of components set forth in the foregoing description or illustrated in the accompanying drawings. The methods and apparatus can be implemented in other embodiments and practiced or carried out in various ways.

Specific implementations are provided here for illustrative purposes only and are not intended to be limiting.

The phraseology and terminology used in this disclosure is for the purpose of description and should not be regarded as limiting. The use of "including", "comprising", "having", "including" and variations thereof herein is intended to be inclusive of the items listed below and equivalents thereof as well as additional items.

References to “or (or)” shall be construed such that any term stated using “or (or)” refers to one, more than one, and all of the terms of the statement. can be

All references to front, rear, left, right, top, bottom, top, bottom, width, length, and front and back are intended for convenience of description. Such references are not limited to any one positional or spatial orientation of the components of this disclosure. Accordingly, the above description and drawings are exemplary only.

1 acoustic wave device 2 wiring board 3 device chip 3a piezoelectric substrate 3b, 3d wiring pattern 3c multiple electrodes 4 bump 5 sealing resin 10 wiring area 31 resonator 32 reflector

The acoustic wave device according to the present disclosure is
a wiring board;
a device chip provided on the wiring substrate and electrically connected to the wiring substrate;
A sealing resin that seals the device chip while leaving a space between the wiring board and the device chip,
The device chip has, on a main surface facing the wiring substrate,
wiring pattern,
a plurality of electrodes periodically formed in a wiring region, which is a region in which the wiring pattern is provided;
a liquid intrusion prevention pattern provided protruding from the wiring pattern at a position closer to the outer edge of the wiring region than the plurality of electrodes in the wiring region ,
The liquid intrusion prevention pattern has a first portion extending substantially perpendicularly from the wiring pattern, and a second portion extending from the tip of the first portion toward the outer edge of the device chip.

Claims (15)

a wiring board;
a device chip provided on the wiring substrate and electrically connected to the wiring substrate;
a sealing resin that seals the device chip while leaving a space between the wiring board and the device chip;
The device chip has, on a main surface facing the wiring substrate,
wiring pattern,
a plurality of electrodes periodically formed in a wiring region, which is a region in which the wiring pattern is provided;
an acoustic wave device comprising: a liquid intrusion prevention pattern provided protruding from the wiring pattern at a position closer to an outer edge of the wiring region than the plurality of electrodes in the wiring region. the plurality of electrodes have a resonator that excites surface acoustic waves and a reflector adjacent to the resonator;
2. The acoustic wave device according to claim 1, wherein said liquid intrusion prevention pattern is provided non-parallel to an orthogonal direction orthogonal to the propagation direction of said surface acoustic wave. 2. The wiring pattern includes bump pads and wiring portions for electrically connecting the bump pads to the plurality of electrodes, and the liquid penetration prevention pattern is provided so as to protrude from the wiring portions. 3. The elastic wave device according to 2. 2. The wiring pattern has a bump pad and a wiring portion electrically connecting the bump pad to the plurality of electrodes, and the liquid penetration prevention pattern is provided so as to protrude from the bump pad. 3. The elastic wave device according to 2. 5. The liquid intrusion prevention pattern according to any one of claims 1 to 4, comprising a first portion extending substantially perpendicularly from the wiring pattern, and a second portion extending from a tip of the first portion toward an outer edge of the device chip. 2. The acoustic wave device according to item 1. The liquid intrusion prevention pattern has a first portion extending substantially perpendicularly from the wiring pattern and a second portion extending from the tip of the first portion in the outer edge direction of the device chip,
3. The acoustic wave device according to claim 2, wherein said first portion is on a line orthogonal to a propagation direction of surface acoustic waves passing through a region between said resonator and said reflector. 7. The acoustic wave device according to claim 5, wherein the liquid intrusion prevention pattern has a curved shape in plan view. The acoustic wave device according to any one of claims 1 to 7, wherein a plurality of the liquid intrusion prevention patterns are formed on one side of the wiring pattern. 2. The acoustic wave device according to claim 1, wherein the liquid intrusion prevention pattern is provided only on a side of the wiring pattern which is substantially perpendicular to the surface acoustic wave propagation direction of the plurality of electrodes. The acoustic wave device according to any one of claims 1 to 9, wherein the liquid intrusion prevention pattern is thinner than the wiring pattern. The acoustic wave device according to any one of claims 1 to 10, wherein the device chip has a substrate in which a piezoelectric substrate and a support substrate made of sapphire, silicon, alumina, spinel, crystal or glass are bonded. The acoustic wave device according to any one of claims 1 to 11, wherein the sealing resin is a thermosetting resin. The acoustic wave device according to any one of claims 1 to 12, comprising a second device chip formed with a bandpass filter having a plurality of surface acoustic wave resonators. The acoustic wave device according to any one of claims 1 to 12, comprising a second device chip formed with a bandpass filter having a plurality of thin film acoustic resonators. A module comprising the acoustic wave device according to any one of claims 1 to 14.

Images