JP2005102114A - Surface acoustic wave device, electronic device, and communication device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a surface acoustic wave device, an electronic device and a communication device which are compact, superior in hermeticity, excellent in isolation, and highly reliable. <P>SOLUTION: A surface acoustic wave device, an electronic device and a communication device using the surface acoustic wave device as a filter are provided with a signal electrode 9 composing a plurality of surface acoustic wave filter portions (filters 18 and 19) having a passband of frequencies different from each other on a piezoelectric substrate 17 and a ground electrode 7 surrounding the surface acoustic wave filter portions. Thus, the surface acoustic wave device, the electronic device and the communication device which are compact and low-profile can be provided. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a surface acoustic wave device, an electronic device, and a communication device having different frequency pass bands used for mobile communication devices such as cellular phones, and more particularly to a surface acoustic wave device as a filter or a duplexer (antenna duplexer). ) Related to what was used.

  Currently, surface acoustic wave devices such as surface acoustic wave filters used in mobile communication devices have extremely low mounting area, low weight, and low height for miniaturization of mobile phone terminals. It is hoped that.

For example, a duplexer shown in FIG. 7 is known as a plurality of surface acoustic wave filters having passbands of different frequencies. In this duplexer, a piezoelectric substrate 113 on which a surface acoustic wave filter is formed is mounted in the cavity portion 112 of the ceramic package 111, and the filter portion and each electrode of the package are electrically connected by a wire 114, and then hermetically sealed with a metal lid. (See, for example, Patent Document 1).
JP 2002-335143 A

  However, the ceramic package having the cavity portion and the connection electrode portion of the wire is large, and it is difficult to reduce the size and weight.

  Further, as shown in FIG. 8, forming the phase matching line 115 for matching the phases of the transmission filter and the reception filter in the package 111 increases the number of stacked layers of the package and hinders a reduction in height. It was.

  Further, in order to prevent electromagnetic interference between the phase matching line 115 and the transmission / reception terminal, in addition to disposing the input / output terminals of the phase matching line 115 at opposite ends of the package, the phase matching line 115 and It is necessary to provide a shield electrode 116 between the transmission / reception terminals.

  In addition, in the case of using a wire, in order to improve isolation by inductive coupling between the wires, there is a limitation on the position where the wire is formed, and the degree of freedom in designing the filter is greatly limited.

  In a surface acoustic wave device in which a piezoelectric substrate provided with signal electrodes (comb-like electrodes) constituting a surface acoustic wave filter unit is mounted face-down on a mounting substrate, the space where the signal electrodes exist is usually air. Is filled with. In this case, when a power of a relatively large power (for example, a power of about 1 W normally used in a CDMA (Code Division Multiple Access) portable terminal) or more is applied, the cause is unknown, but the signal electrode Problems have arisen, such as a short circuit between the electrode fingers and the electrode fingers constituting the electrodes, and the resulting short circuit current causing the electrodes to melt or sparks that blow off not only the signal electrodes but also the piezoelectric substrate.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a surface acoustic wave device, an electronic device, and a communication device each having a plurality of surface acoustic wave filter sections having passbands of different frequencies, which are small and have excellent isolation and reliability. To do.

  In order to solve the above-described problems, a surface acoustic wave device according to the present invention includes: 1) signal electrodes constituting a plurality of surface acoustic wave filter sections having passbands having different frequencies on a piezoelectric substrate; A ground electrode surrounding the surface wave filter portion is provided.

  2) In the surface acoustic wave device according to 1), the ground electrode is formed so as to individually surround each of the plurality of surface acoustic wave filter portions.

  3) In the surface acoustic wave device according to 1) or 2), the surface of the piezoelectric substrate on which the signal electrode and the ground electrode are provided faces the mounting substrate, and the signal of the piezoelectric substrate is At least one of the electrode and the ground electrode is connected to an electrode of the mounting substrate formed wider than the electrode. Here, the mounting substrate is not only a substrate on which a piezoelectric substrate is simply arranged, but also an electric circuit substrate on which an electric circuit for electrical connection with the piezoelectric substrate side is formed or a wiring substrate on which wiring is applied. Etc.

  4) In the surface acoustic wave device according to any one of 1) to 3) above, the surface of the piezoelectric substrate on which the signal electrode and the ground electrode are provided faces the mounting substrate, and the ground electrode, A space surrounded by the piezoelectric substrate and the mounting substrate is hermetically sealed with an inert gas. Here, the inert gas refers to a chemically inert gas, and includes, for example, a rare gas such as nitrogen gas or argon gas.

  5) In the surface acoustic wave device according to any one of 1) to 4) above, the plurality of surface acoustic wave filter units include a filter unit constituting a duplexer.

  6) In the surface acoustic wave device according to any one of 1) to 5) above, the mounting base is provided with phase matching means for matching the phases of the plurality of surface acoustic wave filter portions. It is characterized by that.

  An electronic device according to the present invention is characterized in that the surface acoustic wave device according to any one of 7) to 3) above is mounted on an electric circuit board.

  Furthermore, the communication device of the present invention is characterized in that the surface acoustic wave device according to any one of 1) to 6) is used as a filter.

  According to the surface acoustic wave device of the present invention, a signal electrode constituting a plurality of surface acoustic wave filter sections having passbands having different frequencies on a piezoelectric substrate, and a ground electrode surrounding the plurality of surface acoustic wave filter sections Therefore, an ultra-compact and low-profile surface acoustic wave device can be obtained.

  Further, since the ground electrode is formed so as to individually surround each of the plurality of surface acoustic wave filter portions, a plurality of surface acoustic wave filters having passbands of different frequencies can be improved in isolation. A surface acoustic wave device suitable for a duplexer can be realized. In addition, it is possible to provide a surface acoustic wave device that can sufficiently ensure airtightness and moisture resistance and has excellent long-term reliability.

  Further, one main surface of the piezoelectric substrate provided with the signal electrode and the ground electrode is made to face a mounting base, and at least one of the signal electrode and the ground electrode of the piezoelectric substrate is formed wider than this electrode. In addition, since the effective thickness of the connecting portion is increased because it is connected to the electrode of the mounting substrate, a surface acoustic wave device with better airtightness and moisture resistance can be provided.

  In addition, an inert gas is introduced into a space where the piezoelectric substrate and the mounting substrate face each other, where the signal electrode is provided, and the space is hermetically sealed. When a large amount of electric power is applied, a spark phenomenon that occurs in the signal electrode can be prevented as much as possible.

  In addition, since the surface acoustic wave filter unit includes at least two filter units that constitute a duplexer, for example, an ultra-compact and low-profile surface acoustic wave device having different frequency pass bands can be provided.

  In addition, the surface acoustic wave filter section includes two filters constituting the duplexer in particular, and does not have phase matching means between the two filters, thereby reducing the mounting area. Therefore, it is possible to provide an ultra-compact low-profile surface acoustic wave device having different frequency pass bands.

  Furthermore, according to an electronic device and a communication device provided with such a surface acoustic wave device, it is possible to realize a small and low-profile electronic device and communication device with good sensitivity and high reliability.

  Hereinafter, embodiments of a surface acoustic wave device and a communication device according to the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a cross-sectional view showing a mounting structure of a surface acoustic wave device according to the present invention, FIG. 2 is a plan view of an electrode structure of a surface acoustic wave element constituting the surface acoustic wave device, and FIG. The electrode on the side (surface side) on which the surface acoustic wave element 2 is mounted of the base 3 is shown, and the electrode on the back side of the first mounting base 3 is shown in FIG. FIG. 6 shows a circuit diagram of the communication apparatus. A cross-sectional view taken along line X-X ′ of FIG. 3 is shown in FIG.

  As shown in FIGS. 1 to 3, the surface acoustic wave device of the present invention has a plurality of surface acoustic wave filter portions (18, 19 shown in FIG. 6) having pass bands of different frequencies on a piezoelectric substrate 17. A signal electrode 9 made up of an IDT (Inter Digital Transducer) electrode and a ground electrode 7 surrounding the plurality of surface acoustic wave filter sections are provided. The ground electrodes 7 and 11 are formed so as to individually surround each of the plurality of surface acoustic wave filter portions. Further, the surface of the piezoelectric substrate 17 on which the signal electrode 9 and the ground electrodes 7 and 11 are provided faces the first mounting substrate 3, and at least one of the signal electrode 9 and the ground electrodes 7 and 11 is connected to this electrode. It is connected to the electrode of the first mounting substrate 3 formed wider. The space on the side of the piezoelectric substrate 17 on which the signal electrode 9 and the ground electrodes 7 and 11 are provided faces the first mounting substrate 3 and is surrounded by the ground electrode, the piezoelectric substrate, and the mounting substrate. An inert gas (such as nitrogen or a rare gas (a gas made of a group 18 element such as argon)) or the like is put into the space 5 to hermetically seal the space 5. As described above, since the space 5 is hermetically sealed with the inert gas, even if a relatively large power is applied to the signal electrode 9 or the like constituting the surface acoustic wave filter unit, the signal electrode 9 is generated. The spark phenomenon can be prevented as much as possible.

The plurality of surface acoustic wave filter units include a filter unit constituting a duplexer. The first mounting substrate 3 is a substrate for a module of an electronic device, for example. Furthermore, the communication device of the present invention is characterized by using a surface acoustic wave device having the above-described features as a filter.

  The piezoelectric substrate 17 is made of a piezoelectric single crystal such as a lithium tantalate single crystal, a lanthanite-type single crystal such as a lanthanum-gallium-niobium single crystal, or a lithium tetraborate single crystal. On this piezoelectric substrate 17, a plurality of surface acoustic wave filter portions 18, 19 having pass bands of different frequencies, and surrounding these surface acoustic wave filter portions 18, 19, for example, Al (aluminum), Al A ground electrode 7 made of a laminate of —Cu (copper) alloy or Al—Cu—Mg (magnesium) alloy and Ti (titanium) is formed. Further, the ground electrode 7 is opposed to the ground electrode 8 formed on the first mounting base 3 made of a low-temperature co-fired substrate, a resin substrate, a silicon single crystal substrate, or the like. The ground electrode 8 is, for example, a laminated film made of Cr (chromium) / Ni (nickel) / Au (gold) in the lower layer / upper layer. Further, it is connected by a conductive member 6 made of a solder material described later. Further, the signal electrodes 9 of the two surface acoustic wave filter portions 18 and 19 are electrically connected to the signal electrode 10 formed on the first mounting substrate 3 and the conducting member 6 in the same manner as the ground electrode 7. ing. The two surface acoustic wave filter portions 18 and 19 are separately formed on the piezoelectric substrate 17 in order to improve the isolation.

  The ground electrode 8 formed on the first mounting substrate 3 is connected to the back surface of the first mounting substrate 3 through a via electrode 13 formed by plating such as Ag (silver) paste or Cu—Au alloy. The ground terminal electrode 15 formed in the same manner as the via electrode 13 formed in the above is electrically connected. Similarly, the signal electrode 10 is electrically connected to the signal terminal electrode 14 via the via electrode 13. Further, the signal terminal electrodes 14 formed on the lower surface of the first mounting substrate 3 are not adjacent to each other due to the presence of the ground terminal electrode 15.

  In this embodiment, in place of the conventional hermetic sealing with a metal lid, the conducting member 6 is filled between the ground electrodes 7 and 8 so as to provide hermeticity. As the conductive member 6, a solder material made of Sn (tin) -Ag—Cu alloy, Sn—Sb (antimony) alloy, Sn—Zn (zinc) alloy, Au—Sn alloy, or the like can be used. Further, in order to prevent the conduction member 6 from flowing out, the conduction member 6 is formed to be covered with a protective material 4 made of epoxy resin or the like. The protective material 4 further covers the surface acoustic wave element 2 and prevents the surface acoustic wave element 2 from being damaged by an impact or the like. In addition, about the sealing method, it is not limited to the above-mentioned method, The protective material 4 is good also as what consists of resin and metal excellent in airtightness. In this case, the conductive member 6 does not need to be airtight and can be a conductor paste such as an Ag paste. Furthermore, both the protective material 4 and the conductive member 6 may be made of a material having excellent airtightness. Further, there may be three or more surface acoustic wave filter sections.

  Further, as shown in FIG. 2, the width of the ground electrodes 7 and 11 is almost constant at any location. For example, the illustrated width A of the corner portion (curved portion) of the ground electrode 7 and the illustrated width of the linear portion. B is almost equal. As a result, the amount of solder can be made substantially uniform, and better hermetic sealing can be realized.

  With the above structure, it is possible to prevent deterioration of isolation due to inductive coupling between conventionally used Au wires and to connect the clearance between the cavity portion and the surface acoustic wave element and the wire. Therefore, it is possible to provide an ultra-compact surface acoustic wave device having substantially the same shape as the surface acoustic wave element 2 that realizes an extremely good hermetic seal.

  The filter structures of the two surface acoustic wave filter units may be arbitrary, and for example, a ladder filter, a DMS (Double Mode SAW) filter, a lattice filter, or the like is applicable. These composite filters may be used.

  A separation electrode 12 for separating the surface acoustic wave filter portion 18 and the surface acoustic wave filter portion 19 is formed on the surface acoustic wave element 2 and the first mounting substrate 3, and is electrically connected by the conductive member 6. Yes. In this manner, the surface acoustic wave filter unit 18 and the surface acoustic wave filter unit 19 are separated from each other by forming the separation electrodes 11 and 12 that individually surround the surface acoustic wave filter unit 18 and the surface acoustic wave filter unit 19. Isolation can be further improved than that. As described above, when the surface acoustic wave filter portions 18 and 19 are hermetically sealed by the ground electrodes 7 and 8, airtightness is not necessary at the locations of the separation electrodes 11 and 12. The conducting member 6 in the part of the separation electrodes 11 and 12 does not need to be filled over the whole area of the separation electrodes 11 and 12, and it is only necessary to be conductive even if it is discontinuous. Although it is desirable that the separation electrodes 11 and 12 are electrically connected over the entire region by the conductive member 6, when the isolation property is not strictly required, only the separation electrode 11 or only the separation electrode 12 may be used.

  Although the ground electrodes 7 and 8 and the signal electrodes 9 and 10 are shown in the same shape, it is desirable that the ground electrode 8 extends to the outside of the region where the surface acoustic wave element is mounted. Also, it is desirable that the signal electrode 10 be larger than the signal electrode 9.

  Thus, by making the electrode on the first mounting substrate 3 larger than the electrode of the surface acoustic wave element 2, it is possible to cause a conduction failure or the like even when the mounting deviation between the two substrates occurs. Can be prevented.

  The surface acoustic wave filter unit 18 and the surface acoustic wave filter unit 19 have passbands having different frequencies, for example, a North American cellular filter and a GPS (Global Positioning System) filter or a PCS (Personal Communication Services) filter. And a combination filter such as a GSM (Global System for Mobile Communication) filter and a DCS (Digital Communication System) filter. Most suitable is a filter constituting a duplexer, and a filter that functions simultaneously. That is, the isolation function is required most severely when functioning simultaneously.

  As described above, a surface acoustic wave device suitable for a duplexer can be realized by employing the structure of the present invention with improved isolation.

  Here, a method for manufacturing the surface acoustic wave device will be briefly described. First, cream solder (Sn—Ag—Cu alloy, Sn—Sb alloy, Sn—Zn alloy as a solder material) that becomes the conductive member 6 on the ground electrode 8 and the signal electrode 10 formed on the first mounting substrate 3. An alloy or the like is formed by screen printing and melted in a reflow furnace, and then the flux component in the solder is removed by washing. Next, the first mounting substrate 3 and the surface acoustic wave element 2 are opposed to each other so that the ground electrode 8 and the signal electrode 10 on the first mounting substrate 3 are connected to the ground electrode 7 on the surface acoustic wave element 2. Each signal electrode 9 is aligned. Next, the first mounting substrate 3 and the surface acoustic wave element 2 are collectively reflowed and electrically connected. By performing this reflow in a nitrogen atmosphere, the space 5 can be filled with nitrogen. Here, the first mounting substrate 3 is desirably a large substrate on which a large number of substrates are formed in order to reduce the number of steps. Next, for example, an epoxy resin paste is applied on the surface acoustic wave element 2 and cured to form the protective material 4. Finally, the surface acoustic wave device is individually separated by dicing and completed. As described above, the space where the signal electrode 9 is present is hermetically sealed with an inert gas, so that even if a large amount of power is applied to the signal electrode 9, the gap between the electrode fingers constituting the signal electrode 9 It is possible to prevent as much as possible a spark that is short-circuited and the electrode is melted by a short-circuit current caused by this, or that a spark is generated in the signal electrode 9.

  Next, FIG. 5 shows a perspective view schematically showing an example of an electronic device (including a module) that is miniaturized as described above. In FIG. 5, the surface acoustic wave device 1 does not have a phase matching circuit (or phase matching line) 20 which is one of phase matching means, and is used for a module in which the surface acoustic wave device 1 is mounted (including a wireless module). A phase matching circuit 20 is provided on a second mounting substrate 21 which is the substrate. A duplexer in which surface acoustic wave filters having passbands of different frequencies (transmission frequency and reception frequency) are matched with each other without deterioration in characteristics is provided with meandering as shown in the figure. ) -Shaped phase matching circuit 20 is required. In the transmission filter and the reception filter in the duplexer, since the pass band of the reception filter is set on the high frequency side and the transmission loss has priority over the reception loss, the phase matching circuit 20 is provided on the reception filter side. Is being done. This is to make the input impedance in anticipation of the reception filter from the antenna terminal (indicated by ANT in FIG. 6) infinite in the pass band of the transmission filter, and the signal terminal electrode 14d connected to the transmission circuit. This means that when the signal input from (indicated by Tx in the figure) passes through the transmission filter and reaches the signal terminal electrode 14c, the phase matching circuit 20 and the reception filter are not connected. As a result, the transmission signal is output from the antenna without increasing loss.

  The length of the phase matching circuit 20 is required to be about one-fourth of the wavelength at the frequency of the pass band of the transmission filter, and the mounting base is alumina, and is about 30 mm in the 836.5 MHz band. If the phase matching circuit 20 is incorporated as a meander (meandering) line in the duplexer to achieve miniaturization, in addition to the isolation between the filters, the phase matching circuit 20 and the signal terminal electrode It is necessary to consider isolation.

  FIG. 5 shows an example of an electronic device in which the phase matching circuit 20 is formed on a second mounting substrate 21 outside the surface acoustic wave device 1 serving as a duplexer, and the surface acoustic wave device 1 is connected thereto. Show. Here, the second mounting base 21 is, for example, a module substrate (including a main substrate of a communication device such as a mobile phone). In order to form the phase matching circuit 20 on the second mounting substrate 21, the area of this portion is required, but the isolation is improved accordingly, and the height of the duplexer can be reduced. Further, if the shape of the phase matching circuit 20 formed by the meander line as shown in the figure, it can be incorporated not in the surface layer of the second mounting substrate 21 but in the inner layer, and the mounting area in the surface layer is unnecessary. It is also possible. Note that the same effect can be expected by providing an impedance matching circuit including an inductor and a capacitor instead of the phase matching circuit 20 described above as the phase matching means. A module can be configured without increasing the number of parts by sharing an inductance and a capacitor used in a power supply circuit, a switch circuit, an electrostatic breakdown prevention circuit, and the like. Further, the signal terminal electrodes 14a and 14c are directly connected to each other on the mounting substrate (3, 21) or the surface acoustic wave element 2, and an inductor or a capacitor is connected between the terminal and the ground electrode to achieve matching. Good. In the case of connection on the surface acoustic wave element 2, the separation electrode 11 is excluded. Further, instead of the electronic device shown in FIG. 5, the chip portion excluding the first mounting base 3 in FIG. 1 is provided directly on the second mounting base 21 or other electric circuit board or wiring board. May be.

  As described above, if the communication device includes a module using the ultra-small surface acoustic wave device as a filter, the size of the communication device can be reduced by reducing the size and height of the surface acoustic wave device. In addition, since the isolation can be maintained well and the spark can be suppressed, a surface acoustic wave device excellent in reliability can be realized.

  As described above, according to the surface acoustic wave device 1 of the present invention, the signal electrodes 9 constituting the plurality of surface acoustic wave filter portions having passbands having different frequencies on the piezoelectric substrate 17 and the plurality of surface acoustic waves. Since the ground electrodes 7 and 11 surrounding the wave filter section are provided, the surface acoustic wave device 1 having a small size and a low profile can be obtained.

  Further, since the ground electrodes 7 and 11 are formed so as to individually surround the plurality of surface acoustic wave filter sections (signal electrodes 9), the plurality of surface acoustic wave filters having different frequency passbands are isolated. Therefore, a surface acoustic wave device suitable for a duplexer can be realized. In addition, it is possible to provide the surface acoustic wave device 1 that can sufficiently ensure airtightness and moisture resistance and has excellent long-term reliability.

  In addition, one main surface of the piezoelectric substrate 17 on which the signal electrode 9 and the ground electrodes 7 and 11 are provided faces the upper surface of the first mounting substrate 3, and the signal electrode 9 and the ground electrodes (7, 11 on the piezoelectric substrate 17 are arranged. ) Is connected to the electrodes (8, 10, 12) of the first mounting substrate 3 formed wider than this electrode, so that the effective thickness of this connecting portion is increased, so that it is more airtight. It is possible to provide a surface acoustic wave device 1 having excellent properties and moisture resistance.

  In addition, the piezoelectric substrate 17 provided with the signal electrode 9 and the first mounting substrate 3 are configured to face each other, and are surrounded by the ground electrodes 7 and 11, the piezoelectric substrate 17, and the first mounting substrate 3. Since the space 5 is filled with an inert gas and the space 5 is hermetically sealed, a spark phenomenon generated in the signal electrode 9 can be prevented as much as possible when a relatively large electric power is applied to the surface acoustic wave filter unit. it can.

  Further, since the surface acoustic wave filter unit includes at least two filter units constituting the duplexer, it is possible to provide an ultra-compact and low-profile surface acoustic wave device having passbands with different frequencies.

  In addition, the surface acoustic wave filter unit includes at least two filters constituting a duplexer, and the mounting area can be reduced by not having a matching circuit between these two filters. Therefore, it is possible to provide an ultra-small and low-profile surface acoustic wave device having passbands of different frequencies.

  In addition, by providing phase matching means for matching the phases of the plurality of surface acoustic wave filter sections on the first or second mounting substrate 3 or 21, an ultra-compact, low-profile surface acoustic wave can be obtained. The device 1 or the electronic device can be used.

  Furthermore, according to the communication device including the wireless module including such a surface acoustic wave device, it is possible to realize a small and low-profile communication device with good sensitivity and high reliability.

It is sectional drawing which shows an example of the surface acoustic wave apparatus of this invention. It is a top view which shows the electrode of the surface acoustic wave apparatus of this invention. It is a top view which shows the electrode formed in the surface side of the 1st mounting base | substrate which comprises the surface acoustic wave apparatus of this invention. It is a top view which shows the electrode formed in the back surface side of the 1st mounting base | substrate which comprises the surface acoustic wave apparatus of this invention. It is a perspective view which shows an example of the electronic device of this invention. It is a circuit diagram of the communication apparatus of this invention. It is a top view which shows the conventional surface acoustic wave apparatus. It is a top view which shows a phase matching line.

Explanation of symbols

1: surface acoustic wave device 2: surface acoustic wave element 3: first mounting substrate 4: protective material 5: space 6: conducting member 7, 8: ground electrode 9, 10: signal electrode
11, 12: Separation electrode
13: Via electrode
14: Signal terminal electrode
15: Ground terminal electrode
16: Back electrode
17: Piezoelectric substrate
18, 19: Surface acoustic wave filter
20: Phase matching circuit
21: Second mounting substrate

Claims (8)

An elastic surface comprising a plurality of surface acoustic wave filter portions having pass bands of different frequencies and a ground electrode surrounding the plurality of surface acoustic wave filter portions on a piezoelectric substrate. Wave equipment. The surface acoustic wave device according to claim 1, wherein the ground electrode is formed so as to individually surround each of the plurality of surface acoustic wave filter units. The surface of the piezoelectric substrate on which the signal electrode and the ground electrode are provided faces the mounting substrate, and at least one of the signal electrode and the ground electrode is formed wider than these electrodes. The surface acoustic wave device according to claim 1, wherein the surface acoustic wave device is connected to an electrode. The surface of the piezoelectric substrate on which the signal electrode and the ground electrode are provided faces the mounting substrate, and an inert gas is introduced into a space surrounded by the ground electrode, the piezoelectric substrate, and the mounting substrate, and is hermetically sealed. 4. The surface acoustic wave device according to claim 1, wherein the surface acoustic wave device is sealed. 5. The surface acoustic wave device according to claim 1, wherein the plurality of surface acoustic wave filter units include a filter unit constituting a duplexer. 6. The surface acoustic wave device according to claim 1, wherein a phase matching means for matching phases of the plurality of surface acoustic wave filter portions is provided on the mounting substrate. An electronic device comprising the surface acoustic wave device according to claim 3 mounted on an electric circuit board. A communication apparatus using the surface acoustic wave device according to claim 1 as a filter.

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