JP2006210994A - Mounting structure of surface acoustic wave element, high frequency module and communication apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mounting structure exhibiting high mounting reliability and high mounting yield while sustaining high airtightness of a SAW filter having a bridge electrode. <P>SOLUTION: In the mounting structure of a surface acoustic wave element comprising the surface acoustic wave element having a pair of transmitting I/O terminals 32a, 32b, a pair of receiving I/O terminals 33a, 33b, a ring terminal 34 arranged to surround these transmitting/receiving terminal groups, and a bridge terminal 35 on the mounting surface side of an element substrate 30, and an external circuit board having a pair of transmitting I/O terminals 37a, 37b, a pair of receiving I/O terminals 38a, 38b, a ring electrode 39 arranged to surround these transmitting/receiving terminal groups, and a bridge terminal 40 formed on the surface of a substrate 36, and mounting the surface acoustic wave element on the surface of the external circuit board, both ends of the bridge terminal 40 on the surface of the external circuit board are spaced apart by 0.1 mm or more from the ring electrode 39 or the widths of the both ends of the bridge terminal 40 are made thinner than the line width of the ring electrode 39. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a small-sized, high-performance, low-cost high-frequency module integrally configured with a high-frequency power amplifying device, a high-frequency filter device, and a high-frequency demultiplexer device used in mobile communication devices such as mobile phones, and communication equipment using the same. It is about.

  In recent years, cellular phones have been widely used, and functions and services of cellular phones have been improved. In such a cellular phone, a high-frequency signal processing circuit necessary for the configuration of each transmission / reception system is mounted on a substrate.

  In a general configuration of a conventional high-frequency signal processing circuit, a transmission duplexer and a reception duplexer are provided for switching between a reception signal input from an antenna and a transmission signal fed to the antenna.

  The radio signal that has entered from the antenna is input to the reception duplexer through a matching circuit provided in the preceding stage of the reception duplexer, where the reception signal is selectively passed. The received signal is amplified by a low noise amplifier and supplied to a signal processing circuit.

  On the other hand, the transmission signal is passed through a high frequency filter that allows transmission signals in a predetermined transmission pass band to pass through, and is transmitted to the high frequency power amplifier circuit. The high frequency power amplifier circuit amplifies the power of the transmission signal and supplies it to the transmission duplexer.

  Conventionally, the transmitting and receiving duplexers, the matching circuit, the high frequency power amplifier circuit, the high frequency filter, and the like are each manufactured as individual components and discretely mounted on the upper surface of the substrate. Recently, as the transmission and reception duplexers, those using bare SAW chips that are directly flip-chip mounted using solder on the surface of a predetermined substrate have been proposed.

  FIG. 8 is a schematic cross-sectional view showing an example of a high-frequency module. The high-frequency module shown in FIG. 8 has a power amplification semiconductor element 52 mounted on the surface of a dielectric substrate 51 and is connected to an electrode on the surface of the dielectric substrate 51 by wire bonding. Further, the SAW chip 53 is flip-chip mounted directly on the surface of the dielectric substrate 51 as a duplexer for transmission and reception. Further, a filter 54 is mounted on the surface of the dielectric substrate 51, and a coupler 55, a branching circuit 56, a matching circuit 57, and the like are formed in the dielectric substrate 51 by a wiring pattern. In addition, input / output and power line terminals 58 and other ground terminals 59 are formed on the back surface of the dielectric substrate 51. (For example, refer to Patent Documents 1 and 2).

  In addition, in order to reduce the size of the high-frequency module, it is possible to further reduce the size of the duplexer by configuring two filters for transmission and reception with one bare SAW chip.

  FIG. 9 shows (a) an exploded perspective view of a bare SAW chip mounting structure provided with two filters for transmission and reception, and a zz sectional view in (b) and (a). According to FIG. 8, the SAW filter is provided with a reception filter and a transmission filter on the mounting surface side of the piezoelectric substrate 60. That is, an IDT electrode 61a and input / output terminals 62a and 62b are formed for reception, and similarly, an IDT electrode 61b and input / output terminals 63a and 63b are formed for transmission. These electrodes and terminals are surrounded by a ring-shaped grounding terminal 64. The reception filter formation region and the transmission filter region are separated by a bridging terminal 65.

  On the other hand, on the surface of the dielectric substrate 66, input / output electrodes 67a and 67b for reception and input / output electrodes 68a and 68b for transmission are formed at positions facing the terminals of the SAW filter. A ring-shaped electrode 69 is formed. Similarly to the SAW filter, the reception filter formation region and the transmission filter region are separated by the bridging electrode 70. Normally, both the ring-shaped electrode 69 and the bridging electrode 70 are formed with the same line width.

When the SAW filter is mounted on the surface of the dielectric substrate 66, solder is applied to the surfaces of the input / output electrodes 67a, 67b, 68a, 68b, the ring-shaped grounding electrode 69, and the bridging electrode 70 on the surface of the dielectric substrate 66. The SAW filter is flip-chip mounted on the surface of the dielectric substrate 66 by applying a conductive adhesive such as, and placing the SAW filter thereon and performing reflow. Thus, the input / output electrodes 67a, 67b, 68a, 68b are hermetically sealed by the conductive adhesive existing between the ring-shaped grounding electrode 69 and the ring-shaped grounding terminal.
JP 2002-43977 A Japanese Patent No. 3108107

  In such a SAW filter mounting structure, when the conductive adhesive is uniformly applied to the electrodes on the surface of the dielectric substrate 66, the height of the adhesive is also the same if the line width of the portion where the conductive adhesive is applied is the same. Although the same, when the bridging electrode 70 is partially connected to the ring-shaped electrode 69, as shown in FIG. A phenomenon occurs in which the solder of the T-shaped portion at the intersection of the electrode 70 and the ring-shaped grounding electrode 69 becomes high.

  Thus, when the height of the solder is partially increased, when the SAW filter is mounted on the surface of the dielectric substrate, a mounting failure occurs, and as a result, there is a problem that airtightness due to the solder is impaired.

  Therefore, according to the present invention, even in a mounting pattern of a SAW filter having such a bridging electrode, mounting reliability can be obtained while maintaining high airtightness of the SAW filter, and mounting of a surface acoustic wave element having a high mounting yield is achieved. An object of the present invention is to provide a structure, a high-frequency module, and a communication device.

  The surface acoustic wave element mounting structure according to the present invention includes a pair of transmitting input / output terminals, a pair of receiving input / output terminals, and a ring disposed so as to surround these transmitting / receiving terminal groups on the mounting surface side of the element substrate. A surface acoustic wave device comprising: a strip-shaped terminal; a transmitting terminal; and a bridging terminal provided at a position that divides the receiving input / output terminal into independent regions; A pair of input / output electrodes for transmission, a pair of input / output electrodes for reception, a ring electrode disposed so as to surround the group of transmission / reception electrodes, the input / output electrodes for transmission, and the input / output electrodes for reception And mounting the surface acoustic wave element by mounting the surface acoustic wave element on the surface of the external circuit board. In the structure, on the surface of the external circuit board Characterized in that the opposite ends of the cross electrode formed by 0.1~0.5mm away from the ring electrode.

  In addition, another surface acoustic wave device mounting structure of the present invention surrounds a pair of transmission input / output terminals, a pair of reception input / output terminals, and a group of these transmission / reception terminals on the mounting surface side of the element substrate. A surface acoustic wave device comprising: a ring-shaped terminal disposed; a transmitting input / output terminal; and a bridging terminal provided at a position that divides the receiving input / output terminal into independent regions; A pair of transmission input / output electrodes, a pair of reception input / output electrodes, a ring-shaped electrode arranged so as to surround these transmission / reception electrode groups, and the transmission input An external circuit board on which an output electrode and a bridging electrode provided at a position to divide the receiving input / output electrode into independent regions are formed, and the surface acoustic wave is formed on the surface of the external circuit board. Mounting structure of surface acoustic wave element with element mounted Fraud and mitigating risk width of both end portions of the bridge electrode in the external circuit substrate surface, characterized by being thinner than the line width of the ring-shaped electrode.

  According to the invention, the terminal group of the surface acoustic wave element is flip-chip mounted on the electrode group of the module substrate by solder bumps or Au bumps.

  The width of the ring electrode on the module substrate is preferably 0.1 mm or more.

  Furthermore, it is desirable that the width of the ring-shaped terminal of the surface acoustic wave element is smaller than the width of the ring-shaped electrode on the module substrate side to be connected.

  The high-frequency module according to the present invention includes a power amplifier including at least a power amplification semiconductor element constituting a high-frequency unit and a matching circuit, a directional coupler for detecting the output of the power amplifier, and a transmission / reception signal. And the duplexer is configured by a surface acoustic wave element and mounted on the surface of the module substrate, and the mounting of the surface acoustic wave element on the surface of the module substrate is performed as described above. It is characterized by comprising a mounting structure.

  According to the present invention, both ends of the bridging electrode on the surface of the external circuit board are formed 0.1 to 0.5 mm apart from the ring-shaped electrode, or both ends of the bridging electrode on the surface of the external circuit board. By making the width of the part thinner than the line width of the central part of the bridging electrode, the thickness of the solder is partially increased at the T-shaped part of the ring-shaped electrode and bridging electrode on the external circuit board side. Can be suppressed. As a result, when the SAW filter is flip-chip mounted on the external circuit board, it is possible to suppress a decrease in reliability due to a hermetic sealing failure or a decrease in yield due to the occurrence of a mounting failure, and an elastic surface for mass production. A wave element mounting structure can be provided. Specifically, the reliability of a high-frequency module that handles communication signals in a communication device can be increased, and the reliability of a communication device such as a mobile communication terminal can be increased.

  Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

  FIG. 1 is a block diagram of a CDMA dual-band high-frequency signal processing circuit used for mobile communication devices such as mobile phone devices.

  In this CDMA dual band system, a GPS reception band of 1.5 GHz is used in order to use two transmission / reception systems having a frequency band of the cellular system 800 MHz band and the PCS system 1.9 GHz band and a positioning function by GPS (Global Positioning System). It consists of one receiving system with a band.

  In FIG. 1, 1 is an antenna, 2 is a duplexer including an LPF and an HPF for dividing a frequency band, 3a is a SAW duplexer that separates a transmission system in the 1.9 GHz band, and 3b is a SAW duplexer that separates the reception system. 4a is a SAW duplexer that separates the transmission system of the 800 MHz band, and 4b is a SAW duplexer that separates the reception system. Reference numeral 12 denotes a SAW filter for passing a GPS signal taken from the duplexer 2. Reference numerals 3c and 4c denote matching circuits that rotate the phase of the received signal.

  In the transmission system, the cellular transmission signal output from the transmission signal processing circuit RFIC 17 is subjected to noise reduction by the BPF 9 having a SAW filter and transmitted to the high frequency power amplifier circuit 7. The PCS transmission signal output from the transmission signal processing circuit RFIC 17 is subjected to noise reduction by the BPF 10 having a SAW filter and transmitted to the high-frequency power amplifier circuit 8.

  The high frequency power amplifier circuits 7 and 8 are driven at a frequency of 800 MHz band and 1.9 GHz band, respectively, and amplify transmission power. The amplified transmission signal passes through the directional couplers 5 and 6 and is input to the SAW duplexers 4a and 3a.

  The directional couplers 5 and 6 have a function of monitoring the level of the output signal from the high-frequency power amplifier circuits 7 and 8 and performing auto power control of the high-frequency power amplifier circuit based on the monitor signal. , And input to the detection circuit 11.

  On the other hand, the reception system includes low-noise amplifiers LNAs 14 and 13 that amplify the reception signals separated by the SAW duplexers 4b and 3b, and high-frequency filters 16 and 15 that remove noise from the reception signals. The reception signals that have passed through the high frequency filters 16 and 15 are transmitted to the reception signal processing circuit RFIC 18 and processed. The GPS signal separated by the GPS SAW filter 12 is subjected to signal processing by the reception signal processing circuit RFIC18.

The structure of the duplexer is not limited, but preferably 36 ° Y cut-X propagation LiTaO ₃ crystal, 64 ° Y cut-X propagation LiNbO ₃ crystal, 45 ° X cut-Z propagation LiB ₄ O ₇ crystal, etc. A comb-shaped IDT (Inter Digital Transducer) electrode is formed on a substrate made of

  The configuration of the high-frequency power amplifier circuit is not limited, but preferably has a function of amplifying a high-frequency signal, and a GaAsHBT (gallium arsenide heterojunction bipolar transistor) structure or a P-HEMT structure in order to reduce the size and increase the efficiency. The semiconductor device includes a GaAs transistor, a silicon or germanium transistor.

  In a mobile communication device including a high-frequency signal processing circuit having the above-described configuration, there is a great demand for miniaturization and weight reduction of each part. In consideration of these requirements, the high-frequency signal processing circuit achieves desired characteristics. It is modularized in units that can be done.

  That is, as shown by a thick dotted line 22 in FIG. 1, a demultiplexing system including a demultiplexer 2, SAW duplexers 3a, 3b, 4a, 4b, high-frequency power amplifier circuits 7, 8, directional couplers 5, 6 and the like. The circuit and the transmission system circuit form one high-frequency module 22 formed on one substrate.

  A mounting method is also possible in which the high-frequency module 22 is divided into a high-frequency module in the 800 MHz band and two high-frequency modules in the 1.9 GHz band. Further, a module including the low noise amplifiers LNA 13 and 14 and the receiving high frequency filters 15 and 16 may be added.

  Hereinafter, description will be given based on one high-frequency module 22 including two frequency bands of 800 MHz band and 1.9 GHz band.

  FIG. 2 shows a schematic plan view of the high-frequency module 22, and FIG. 3 shows a schematic cross-sectional view thereof. The high-frequency module 22 includes a multilayer substrate 23 on which nine dielectric layers having the same size and shape are stacked.

  On the surface layer of the multilayer substrate 23, in addition to various patterns and various chip components, BPF 9, 10, a SAW filter 12 for GPS, bare SAW chips 3a, 4a, 3b, 4b as SAW duplexers, and a high-frequency power amplifier circuit 7, 8 are mounted and mounted on a conductor pattern on a dielectric layer with solder or the like.

  The power amplification semiconductor elements 24 and 25 are connected to the conductor pattern on the multilayer substrate 23 by wire bonding. Around the power amplifying semiconductor elements 24 and 25, power amplifying matching circuits 26 and 27 that are also part of the high-frequency power amplifying circuits 7 and 8 are formed by chip parts or conductor patterns.

  The power amplification semiconductor elements 24 and 25, the power amplification matching circuits 26 and 27, and the like may be mounted on the back surface of the multilayer substrate.

  Matching circuits 3 c and 4 c and directional couplers 5 and 6 are housed inside the multilayer substrate 23, and a DC-cut coupling capacitor 28 is provided between the power amplification semiconductor elements 24 and 25 and the BPFs 9 and 10. , BPFs 9 and 10 and a capacitor 29 are provided between the ground.

  In terms of structure, conductor patterns such as distributed constant lines, coupled lines, distributed capacitors, resistors, and the like that constitute these internal elements are respectively formed in the dielectric layers. For example, the coupling lines constituting the directional couplers 5 and 6 are respectively formed on two overlapping dielectric layers. In each dielectric layer, via hole conductors necessary for vertically connecting circuits are formed in a vertical direction across a plurality of layers. In particular, a thermal via 50 penetrating vertically through the dielectric layer is provided in order to release heat generated in the power amplification semiconductor elements 24 and 25.

  In FIG. 4, the conductor pattern figure of the back surface of a high frequency module is shown. On the back surface of the dielectric substrate 23, an input / output terminal of a module for connecting to an external circuit, a power supply terminal 42, and a ground terminal 43 are provided.

  5A is an exploded perspective view of a mounting structure of a bare SAW chip including two filters for transmission and reception, and FIG. 5B is a cross-sectional view taken along line P-P in FIG. According to FIG. 5, the SAW filter is provided with a reception filter and a transmission filter on the mounting surface side of the piezoelectric substrate 30. That is, an IDT electrode 31a and input / output terminals 32a and 32b are formed for reception, and similarly, an IDT electrode 31b and input / output terminals 33a and 33b are formed for transmission. These electrodes and terminals are surrounded by a ring-shaped grounding terminal 34. In addition, the reception filter formation region and the transmission filter region are separated by a bridging terminal 35.

  On the other hand, on the surface of the dielectric substrate 36, input / output electrodes 37a and 37b for reception and input / output electrodes 38a and 38b for transmission are formed at positions facing the terminals of the SAW filter. A ring-shaped grounding electrode 39 is formed. Similarly to the SAW filter, the reception filter formation region and the transmission filter region are separated by the bridging electrode 40.

  When the SAW filter is mounted on the surface of the dielectric substrate 66, solder is applied to the surfaces of the input / output electrodes 37a, 37b, 38a, 38b, the ring-shaped grounding electrode 39, and the bridging electrode 40 on the surface of the dielectric substrate 66. The SAW filter is mounted on the surface of the dielectric substrate 36 by applying an adhesive 41 such as the above, placing a SAW filter thereon, and performing solder reflow. In this case, for example, from the viewpoint of solder wettability, the electrode of the dielectric substrate is preferably plated with Ni as a gold base. As the conductive adhesive, Au may be used instead of solder. As a result, the IDT electrodes 31a, 31b, the input / output terminals 32a, 32b, 33a, 33b, the input / output electrodes 37a, 37b, 38a, 38b are connected between the ring-shaped grounding electrode 39 and the ring-shaped grounding terminal 34. Is hermetically sealed by an adhesive 41 such as solder. Thereafter, the power amplifying semiconductor elements 24 and 25 are mounted and connected by wire bonding, and the entire surface of the dielectric substrate is sealed with an epoxy resin or the like to obtain a high-frequency module.

  According to the present invention, as shown in FIG. 6A, it is important that both ends of the bridging electrode 40 on the surface of the dielectric substrate 36 on which the SAW filter is mounted are formed away from the ring electrode 39. Thus, by forming the both ends of the bridging electrode 40 apart from the ring-shaped electrode 39, the thickness of the bridging electrode 40 and the ring-shaped electrode 39 is substantially uniform as shown in FIG. 6B. Therefore, the mounting reliability of the SAW filter can be increased, the hermetic sealing reliability by the ring electrode 39 can be increased, and the yield in mounting can be improved. If the bridging electrode 40 is formed away from the ring-shaped electrode 39, the solder swell can be prevented and the effect of the present invention can be achieved. However, if the bridging electrode 40 is too far away, the reception filter formation region and the transmission filter formation region are separated. Since the role of the bridging electrode 40 for breaking is impaired and the transmission signal may interfere with the reception signal, the upper limit is preferably set to 0.5 mm. Accordingly, the separation distance a is preferably 0.1 to 0.5 mm.

  Further, the width b of the central portion of the bridging electrode 40 is desirably 0.1 to 0.3 mm. The width b is 0.1 mm or more, so that the printability of the solder can be maintained, and the mounting property on the surface of the dielectric substrate 66 can be improved. By setting the width b to 0.3 mm or less, the mounting area is reduced. Because it can.

  The width c of the ring electrode 39 is preferably 0.1 to 0.3 mm. This is because the airtightness by sealing can be improved by setting the width b to 0.1 mm or more, and the mounting area can be reduced by setting the width b to 0.3 mm or less.

  The width b of the bridging electrode 40 is desirably the same as or smaller than the width c of the ring-shaped electrode 39. Thereby, it is possible to prevent the solder height of the bridging electrode 40 from being locally increased.

  Further, in the present invention, for the same purpose as described above, as shown in FIG. 7A, the width d of both ends of the bridging electrode 40 on the surface of the dielectric substrate 36 on which the SAW filter is mounted is set to be a ring electrode. The object of the present invention can also be achieved by making the line width c smaller than 39. That is, by making the line width at both ends narrower than the ring-shaped electrode 39, the absolute amount of solder at the T-shaped portion with the ring-shaped electrode 39 is reduced, and as shown in FIG. Can be prevented from occurring.

  7B, the both ends of the bridging electrode 40 are formed so as to be gradually smaller than the line width of the central part of the bridging electrode 40 and so as to be thinner than the ring-shaped electrode 39. In this case, the line width d at the contact portion of the bridging electrode 40 with the ring electrode 39 is desirably 50% or less, 40% or less, and further 30% of the line width c of the ring electrode 39. Furthermore, it is desirable that it is 50 μm or less, particularly 40 μm or less.

  In addition, when making the width | variety of the both ends of the bridging electrode 40 narrower than the line width of the ring-shaped electrode 39, it is not limited to the structure of FIG. 7, For example, the line | wire width of predetermined length part from both ends is set. The line width of the bridging electrode 40 as a whole can be reduced as described above. However, when the line width of the entire bridging electrode 40 is reduced, the bridging electrode 40 also has a function of increasing the mounting strength at the time of mounting. Therefore, the line width b at the center of the bridging electrode 40 may be 50 μm or more. desirable.

  The high-frequency module according to the present invention is composed of a ceramic dielectric substrate 23 and a conductor pattern or via conductor disposed on the surface or inside thereof, and a conductor paste is formed on the surface of a sheet molded body made of ceramics. As a vertical conductor, a through hole is formed in the sheet-like molded body and a conductor paste is filled to form a via conductor, and then the sheet-like molded body and the conductor paste are laminated. And a multilayer wiring structure in which ceramic dielectric layers and conductor patterns are alternately arranged.

  The dielectric substrate in the high frequency module of the present invention is preferably composed of at least one selected from the group of low-temperature fired ceramics such as alumina ceramics, mullite ceramics, and glass ceramics. In particular, a low-resistance conductor such as Cu or Ag can be used as a conductor for forming a conductor pattern or a via conductor, and from the convenience that it can be formed by co-firing with these low-resistance conductors, at 1000 ° C. or less. Low temperature fired ceramics such as fireable glass ceramics are most desirable.

  Next, an example in which the high-frequency module according to the present invention is manufactured will be described.

A mixture in which 10 parts by mass of B in terms of B ₂ O ₃ and 5 parts by mass of Li in terms of LiCO ₃ are added to 100 parts by mass of the main component represented by 0.95 mol MgTiO ₃ -0.05 mol CaTiO ₃ . In addition, an acrylic resin as an organic binder and toluene as a solvent were added and mixed to prepare a slurry, which was then formed into a sheet on a carrier film by a doctor blade method to prepare a green sheet having a thickness of 50 to 150 μm.

  Next, through holes were formed in the green sheet by punching, and an Ag conductor paste was filled therein to form a via conductor having a diameter of 150 μm. The conductor paste is prepared by adding acrylic resin and toluene to Ag powder and mixing them homogeneously. And the electrode and planar conductor layer which printed the said copper paste by the screen printing method on the surface of this green sheet were formed.

  Thereafter, 5 to 12 green sheets obtained in the same manner were laminated and pressed to form a green sheet laminate.

  The laminated body is heat-treated in a nitrogen atmosphere at 400 to 750 ° C. to decompose and remove organic components in the green sheet and the conductor paste, and then fired in a nitrogen atmosphere at 900 ° C. for 1 hour to obtain a high-frequency module. A dielectric substrate was prepared.

  The input / output electrode, the ring electrode and the bridging electrode formed on the SAW chip mounting portion on the substrate surface were plated with Ni.

  The shapes of the ring electrode and the bridging electrode were as shown in Table 1, and module substrates having various patterns of electrodes were produced.

  Then, a solder made of Sn—Ag—Cu is applied to these module substrates, and a SAW chip is placed thereon, and then reflow processing is performed at 260 ° C., so that the SAW chip is applied to the surface of the dielectric substrate. Flip chip mounted.

50 SAW chips were mounted on each substrate, and as a mounting failure at that time, the airtightness test on the SAW chip was checked using helium, and the ratio of defective products is shown in Table 1. Specifically, the sample was held in a pressurized atmosphere of 5.3 kg / cm ² for 2 hours, and then held in a reduced pressure of 5 × 10 ⁻⁸ atm · cc / cm ² to detect He. The product was regarded as a defective product.

  Table 1 shows that the conventional bridging electrode and ring-shaped electrode patterns are the conventional ones shown in FIG. In No. 1, the incidence of defects was as high as 5% or more.

  On the other hand, sample no. In all of Nos. 2 to 5, the defect rate could be suppressed to 2% or less. Similarly, the sample No. 1 in which the line width at both ends of the bridging electrode is narrower than the line width of the ring electrode. 7 to 11, the defect rate could be suppressed to 2% or less.

A typical block diagram of a CDMA dual-band high-frequency signal processing circuit is shown. The schematic plan view of the high frequency module which comprises the circuit of FIG. 1 is shown. The schematic sectional drawing of the high frequency module of FIG. 2 is shown. The conductor pattern figure of the back surface of an example of the high frequency module of this invention is shown. 1 shows a mounting structure of a SAW chip according to the present invention, where (a) is an exploded perspective view, and (b) is a schematic sectional view when the SAW chip is flip-chip mounted. It is (a) top view for demonstrating an example of the pattern of the electrode on the surface of the dielectric substrate in this invention, and (XX) sectional drawing in (a). It is (a) top view for demonstrating the other example of the pattern of the electrode of the dielectric substrate surface in this invention, and YY sectional drawing in (b) (a). It is a schematic sectional drawing which shows an example of the conventional high frequency module. 1 shows a conventional mounting structure of a SAW chip, in which (a) is an exploded perspective view, and (b) is a ZZ sectional view in (a).

Explanation of symbols

22... High frequency module 23... Dielectric substrates 24 and 25... Power amplification semiconductor elements 26 and 27... Power amplification matching circuit 30. 31b IDT electrodes 32a and 32b Input / output terminals for reception 33a and 33b Input / output terminals for transmission 34... Ring-shaped grounding terminal 35 and bridge terminal 36 Dielectric substrates 37a, 37b, receiving input / output electrodes 38a, 38b, transmitting input / output electrodes 39, ... ring-shaped grounding electrode 40, ... bridging electrodes

Claims (7)

On the mounting surface side of the element substrate, a pair of transmission input / output terminals, a pair of reception input / output terminals, a ring-shaped terminal arranged so as to surround these transmission / reception terminal groups, and the transmission input / output terminals, A surface acoustic wave device comprising: a bridging terminal provided at a position where the receiving input / output terminal is divided into independent regions;
On the substrate surface, a pair of transmission input / output electrodes, a pair of reception input / output electrodes, a ring electrode disposed so as to surround these transmission / reception electrode groups, the transmission input / output electrodes, and the reception input An external circuit board formed with a bridging electrode provided at a position to divide the output electrode into independent regions;
In the mounting structure of the surface acoustic wave element formed by mounting the surface acoustic wave element on the surface of the external circuit board,
A surface acoustic wave element mounting structure, wherein both ends of the bridging electrode on the surface of the external circuit board are separated from the ring electrode by 0.1 mm or more. On the mounting surface side of the element substrate, a pair of transmission input / output terminals, a pair of reception input / output terminals, a ring-shaped terminal arranged so as to surround these transmission / reception terminal groups, and the transmission input / output terminals, A surface acoustic wave device comprising: a bridging terminal provided at a position where the receiving input / output terminal is divided into independent regions;
A pair of transmission input / output electrodes, a pair of reception input / output electrodes, a ring-shaped electrode arranged so as to surround these transmission / reception electrode groups, and the transmission input An external circuit board formed with an output electrode and a bridging electrode provided at a position where the receiving input / output electrode is divided into independent regions;
In the mounting structure of the surface acoustic wave element formed by mounting the surface acoustic wave element on the surface of the external circuit board,
The surface acoustic wave element mounting structure, wherein the width of both ends of the bridging electrode on the surface of the external circuit board is narrower than the line width of the ring-shaped electrode. 3. The surface acoustic wave element mounting according to claim 1, wherein the terminal group of the surface acoustic wave element is flip-chip mounted on an electrode group of the module substrate by solder bumps or Au bumps. Construction. 4. The surface acoustic wave device mounting structure according to claim 1, wherein the ring-shaped electrode of the module substrate has a width of 0.1 mm or more. 5. The surface acoustic wave device according to claim 1, wherein a width of the ring-shaped terminal of the surface acoustic wave device is smaller than a width of a ring-shaped electrode on the module substrate side to be connected. 6. Implementation structure. A power amplifier composed of at least a power amplification semiconductor element constituting a high-frequency section and a matching circuit, a directional coupler for detecting the output of the power amplifier, and a duplexer for separating transmission and reception signals, In a high frequency module in which a duplexer is configured by a surface acoustic wave element (SAW) and mounted on a module substrate surface,
6. The high-frequency module according to claim 1, wherein the surface acoustic wave element is mounted on the external circuit board. A communication device comprising the high-frequency module according to claim 6.

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