WO2008029641A1

WO2008029641A1 - Circuit board for wave separator device, wave separator, and communication device

Info

Publication number: WO2008029641A1
Application number: PCT/JP2007/066451
Authority: WO
Inventors: Takeshi Takenoshita; Takanori Ikuta; Wataru Koga
Original assignee: Kyocera Corporation
Priority date: 2006-08-30
Filing date: 2007-08-24
Publication date: 2008-03-13
Also published as: JPWO2008029641A1; JP4926179B2

Abstract

It is an object to improve an isolation characteristic in the inside of a circuit board and an isolation characteristic between the circuit board and its outside. In order to achieve the object, the circuit board is comprised of a plurality of mutually stacked dielectric layers (Lb, Ld, Lf), a matching circuit line (6) surrounded with a plurality of the dielectric layers for adjusting an impedance between first and second filter elements provided with mutually different passing frequency bands, a first signal transmitting line (7) formed on a plurality of the dielectric layers ranging from the top to the bottom for electrically connecting the first filter elements with a first signal transmitting terminal, a second signal transmitting line (8) for electrically connecting the second filter elements with a second signal transmitting terminal, and first grounding conductors (30, 44) arranged between the first signal transmitting line and the matching circuit line, also arranged between the first and second signal transmitting lines and further arranged to surround the first signal transmitting line.

Description

Specification

Circuit board for duplexer device, duplexer, and communication apparatus

Technical field

The present invention relates to a circuit board for mounting a duplexer, a duplexer, and a communication device using the same.

Background art

[0002] In recent years, a duplexer installed in a portable communication terminal such as a cellular phone has a surface acoustic wave filter (SAW filter) in which comb-like electrodes are formed on a piezoelectric substrate, A so-called FBAR (Film Bulk Acoustic Resonator) filter using a thin film resonator in which electrodes are provided so as to be sandwiched from above and below the piezoelectric thin film is employed.

[0003] These duplexers have the advantage that they can be made very compact compared to the duplexers using dielectric filters that have been used in the past, and are portable devices. For communication terminals that require the installation of multiple high-functionality applications for a certain size, this is an essential component.

As shown in FIG. 15, the duplexer transmits the transmission signal input from the transmission circuit connected to the signal terminal 701 to the antenna terminal 703 via the signal line 707 and the signal line 709. A transmission filter 704, and a reception filter 705 that transmits a reception signal input from the antenna terminal 703 to a reception circuit connected to the signal terminal 702 via the signal line 710 and the signal line 708. . This duplexer includes an antenna terminal (common terminal) 703 to which the transmission filter 704 and the reception filter 705 are connected in order to share the antenna for transmission and reception.

[0005] These signal terminals 701 and 702, common terminal 703, transmission filter 704, reception filter

When the 705 and the signal lines 707 to 710 are simply connected, a signal input from the transmission circuit and transmitted through the transmission filter 704 leaks to the reception filter 705. For this reason, the impedance from the antenna to the transmission circuit is almost infinite for the frequency band for reception, while the impedance from the transmission circuit to the reception circuit is almost infinite for the frequency band for transmission. A matching circuit 706 is provided for adjustment. [0006] This matching circuit 706 is usually composed of one or more inductors and other components. In order to meet the demand for miniaturization of circuits and components used in portable communication terminals, the matching circuit 706 is also a duplexer. Therefore, there is a need for a matching circuit-integrated duplexer that is housed in the element. In order to reduce the size of the matching circuit integrated duplexer, it is necessary to reduce the number of elements used in the matching circuit 706 itself as much as possible, and the configuration in which the number of parts of the matching circuit 706 is minimized is as follows. In this configuration, an inductor is provided between the common terminal 703 and the ground terminal.

[0007] By the way, the inductance value required in the matching circuit 706 is a force that depends on the frequency band using the demultiplexer. The frequency band near 2 GHz is about 1 to 6 ηΗ, and the frequency band near 900 MHz is several nH to About a dozen nH. Examples of a method for placing such a matching circuit 706 in the duplexer include a circuit board on which a board on which a filter element is formed is mounted, and an inductor using a line inside the package.

However, when the matching circuit integrated duplexer is reduced in size by such a method, between the matching circuit 706 and the signal line for transmission / reception, and between the signal line for transmission and the signal line for reception When the isolation deteriorates due to electrical interference between the two, problems arise.

[0009] Therefore, it is possible to reduce electrical interference between the matching circuit 706 and the transmission / reception signal line, and between the transmission signal line and the reception signal line, and to achieve good isolation characteristics. In order to achieve this, a technique for providing a ground pattern between a transmission / reception signal line and a matching circuit, and between a transmission signal line and a reception signal line has been proposed (for example, Japanese Patent Application Laid-Open No. 2003-298462). reference).

[0010] However, in the technique described in Japanese Patent Application Laid-Open No. 2003-298462, since the transmission / reception signal line is formed on the outer periphery of the circuit board, an electromagnetic field is generated between the signal lines in the external space of the circuit board. There was a problem that bonding occurred and sufficient isolation was not obtained. In addition, since the signal is radiated to the outside of the circuit board, other components are adversely affected, and the signal (noise) from the external components is easily affected. Disclosure of the invention

The present invention has been made in view of the above problems, and a circuit board for a duplexer device capable of improving the isolation characteristics inside the circuit board and the isolation characteristics between the outside of the circuit board. Provides a duplexer and a communication device using the duplexer Doing that is to do.

[0012] In order to solve the above problem, the duplexer device circuit board according to the first aspect includes a plurality of dielectric layers stacked on each other and surrounded by the plurality of dielectric layers. And a matching circuit line for adjusting the impedance between the first and second filter elements having different pass frequency bands and the plurality of dielectric layers, and the plurality of dielectric layers And a first signal transmission line for electrically connecting the first filter element and the first signal transmission terminal, and the second signal transmission line. A second signal transmission line for electrically connecting the filter element and the second signal transmission terminal; and between the first signal transmission line and the matching circuit line; and Between the first signal transmission line and the second signal transmission line. Setting vignetting, and it was set to and a first grounding conductor surrounding the first signal electrical transmission for lines to.

[0013] Thereby, between the lines inside the circuit board is electrically shielded, and between the signal transmission line surrounded by the grounding conductor and the outside of the circuit board is also electrically shielded. It is possible to reduce electrical interference inside the board and outside the circuit board. As a result, the isolation characteristics inside the circuit board and the isolation characteristics inside the circuit board can be reduced. It can be improved.

[0014] A duplexer device circuit board according to a second aspect is the duplexer device circuit board according to the first aspect, wherein the second signal transmission line includes the plurality of dielectrics. The duplexer device circuit board is surrounded by a body layer and formed from an uppermost layer to a lowermost layer of the plurality of dielectric layers, and the duplexer device circuit board includes the second signal transmission line and the A second grounding line provided between the matching circuit line and between the second signal transmission line and the first signal transmission line and surrounding the second signal transmission line. The conductor was further equipped.

[0015] With this, both the transmission and reception signal transmission lines are electrically shielded between the lines inside the circuit board and are also electrically shielded from the outside of the circuit board. Between the isolation characteristics inside the circuit board and the outside of the circuit board Isolation characteristics can be further improved.

[0016] A circuit board for a duplexer device according to a third aspect is the circuit board for a duplexer device according to the first aspect, wherein the first grounding conductor is the plurality of dielectrics. The conductor pattern formed between the layers of one or more dielectric layers adjacent to each other among the layers was included.

[0017] Accordingly, since the grounding conductor surrounding the circumference of the signal transmission line is configured by the conductor pattern formed between the dielectric layers, the grounding conductor can be easily formed.

[0018] A circuit board for a duplexer device according to a fourth aspect is the circuit board for a duplexer device according to the third aspect, wherein the first grounding conductor is the plurality of dielectrics. A plurality of conductor pattern regions respectively formed between layers of a plurality of dielectric layers adjacent to each other, and a plurality of the dielectric layers sandwiched between the plurality of conductor pattern regions, And one or more conductors that are electrically connected to each other.

[0019] A duplexer device circuit board according to a fifth aspect is the duplexer device circuit board according to the fourth aspect, wherein the one or more conductors are used for the first signal transmission. A plurality of conductors provided so as to surround the track were included.

[0020] Thus, by surrounding the signal transmission line with a plurality of grounding conductors that further penetrate the dielectric layer, the isolation characteristic inside the circuit board and the isolation characteristic between the outside of the circuit board can be obtained. Further improvement can be achieved.

[0021] A circuit board for a duplexer device according to a sixth aspect is the circuit board for a duplexer device according to the first aspect, wherein each of the first and second filter elements is a ladder type. It was made to be a finala element.

[0022] A circuit board for a duplexer device according to a seventh aspect is the circuit board for a duplexer device according to the fourth aspect, and is a relative of the first and second filter elements. A filter element having a very high pass frequency band has a resonator in a parallel arm, and the resonator is electrically connected to the first grounding conductor.

[0023] Thereby, by providing a grounding conductor pattern around the signal transmission line, More conductors penetrating the dielectric layer can be arranged between the grounding conductor patterns, and as a result, between the parallel resonator of the filter element having a relatively high pass frequency band and the grounding terminal. Since the inductance of the conductor that electrically connects to the filter element becomes small, the out-of-band attenuation on the low frequency side of the filter element having a relatively high pass frequency band increases.

[0024] A circuit board for a duplexer device according to an eighth aspect is the circuit board for a duplexer device according to the second aspect, wherein the first and second grounding conductors are the plurality. Each of the dielectric layers includes a conductor pattern formed between one or more dielectric layers adjacent to each other.

[0025] With this, the grounding conductor is formed by surrounding the periphery of the signal transmission line with the conductor pattern formed between the dielectric layers, so that the grounding conductor can be easily formed.

[0026] A circuit board for a duplexer device according to a ninth aspect is the circuit board for a duplexer device according to the eighth aspect, wherein the first grounding conductor is the plurality of dielectrics. A plurality of first conductor pattern regions respectively formed between a plurality of sets of dielectric layers adjacent to each other, and a dielectric layer sandwiched between the plurality of first conductor pattern regions. One or more conductors that pass through and electrically connect the plurality of first conductor pattern regions to each other, and the second grounding conductor is mutually connected among the plurality of dielectric layers. A plurality of second conductor pattern regions respectively formed between layers of a plurality of adjacent dielectric layers and a dielectric layer sandwiched between the plurality of second conductor pattern regions, and the plurality One or more conductors electrically connected to each other in the second conductor pattern area of the I included it.

[0027] A circuit board for a duplexer device according to a tenth aspect is the circuit board for a duplexer device according to the ninth aspect, wherein the plurality of first conductor pattern regions are electrically connected to each other. And a plurality of conductors provided so as to surround the first signal transmission line.

[0028] Thus, by surrounding the signal transmission line with a plurality of grounding conductors that further penetrate the dielectric layer, the isolation characteristics inside the circuit board and the outside of the circuit board can be obtained. The isolation characteristics in can be further improved.

[0029] A circuit board for a duplexer device according to an eleventh aspect is the circuit board for a duplexer device according to the ninth aspect, wherein the plurality of second conductor pattern regions are electrically connected to each other. And a plurality of conductors provided so as to surround the second signal transmission line.

[0030] Thus, by surrounding the signal transmission line with a plurality of grounding conductors that further penetrate the dielectric layer, the isolation characteristic inside the circuit board and the isolation characteristic between the outside of the circuit board can be obtained. Further improvement can be achieved.

[0031] A circuit board for a duplexer device according to a twelfth aspect is the circuit board for a duplexer device according to the ninth aspect, wherein each of the first and second filter elements is a ladder type It was made to be a finala element.

[0032] A circuit board for a duplexer device according to a thirteenth aspect is the circuit board for a duplexer device according to the ninth aspect, and is a relative of the first and second filter elements. A filter element having a very high pass frequency band has a resonator in a parallel arm, and the resonator is electrically connected to the first and second grounding conductors.

[0033] Thereby, since the grounding conductor pattern is provided around the signal transmission line, more conductors penetrating the dielectric layer can be arranged between the grounding conductor patterns. Filter element having a relatively high pass frequency band because the inductance of the conductor electrically connecting between the parallel resonator of the filter element having a relatively high pass frequency band and the grounding terminal is reduced. The out-of-band attenuation on the low frequency side increases.

[0034] A circuit board for a duplexer device according to a fourteenth aspect is the circuit board for a duplexer device according to the first aspect, wherein the first filter element is a filter element for transmission. The second filter element force is a receiving filter element.

[0035] A duplexer according to the fifteenth aspect is mounted on the duplexer device circuit board according to any one of the first to fourteenth aspects, and the duplexer device circuit board. The first and second filter elements are provided.

[0036] A duplexer according to a sixteenth aspect is the duplexer according to the fifteenth aspect, wherein the first filter The filter element is a transmission filter element, the second filter element is a reception filter element, and the first and second filter element forces and a common terminal electrically connected to the antenna And one end of the matching circuit is electrically connected to the common terminal, and the other end of the matching circuit that is different from one end of the matching circuit is grounded. I did it.

[0037] A duplexer according to a seventeenth aspect is the duplexer according to the sixteenth aspect, wherein the matching circuit power and a signal in a predetermined frequency band for reception are transmitted from the common terminal to the transmission circuit. The impedance is almost infinite, and the impedance from the transmitting circuit to the receiving circuit is made almost infinite for a signal in a predetermined frequency band for transmission.

[0038] A duplexer according to an eighteenth aspect is the duplexer according to the seventeenth aspect, wherein the frequency band for reception is 869 to 894 MHz, and the frequency band for transmission is 824. -849 MHz.

[0039] A duplexer according to a nineteenth aspect is the duplexer according to the fifteenth aspect, wherein the first and second filter element forces S are each surrounded by an annular electrode portion. did.

[0040] The communication device according to the twentieth aspect is mounted with the duplexer according to any of the fifteenth to nineteenth aspects.

Brief Description of Drawings

FIG. 1 is a block diagram showing a functional configuration of a communication apparatus according to a first embodiment of the present invention.

FIG. 2 is a diagram illustrating a circuit configuration of a duplexer according to the first embodiment of the present invention.

FIG. 3 is a schematic cross-sectional view illustrating the schematic configuration of the circuit board according to the first embodiment of the invention.

FIG. 4 is a diagram illustrating an example of the arrangement of conductor patterns and vias on the circuit board according to the first embodiment of the present invention.

FIG. 5 is a diagram showing an example of the arrangement of conductor patterns and vias on the circuit board according to the first embodiment of the present invention.

FIG. 6 is a top view illustrating the configuration of the surface acoustic wave element according to the first embodiment of the invention.

Yes

FIG. 7 shows an example of the arrangement of conductor patterns and vias on the circuit board according to the second embodiment of the present invention. FIG.

FIG. 8 is a diagram illustrating an example of the arrangement of conductor patterns and vias on a circuit board according to a second embodiment of the present invention.

FIG. 9 is a diagram showing an equivalent circuit of the duplexer according to the second embodiment of the present invention.

FIG. 10 is a diagram showing an arrangement of conductor patterns and vias on a circuit board according to a comparative example.

FIG. 11 is a diagram showing an arrangement of conductor patterns and vias of a circuit board according to a comparative example.

FIG. 12 is a graph showing the isolation characteristics of Examples 1 and 2 and a comparative example.

FIG. 13 is a graph showing the isolation characteristics of Examples 1 and 2 and a comparative example.

FIG. 14 is a graph showing the isolation characteristics of Examples 1 and 2 and a comparative example.

FIG. 15 is a diagram illustrating a circuit configuration of a conventional duplexer.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[0043] <First embodiment>

FIG. 1 is a block diagram showing a functional configuration of the communication apparatus 100 according to the first embodiment of the present invention. The communication device 100 is configured by, for example, a mobile phone or a portable wireless terminal.

As shown in FIG. 1, the communication device 100 mainly includes a control unit 200, a transceiver 300, an antenna 400, an operation unit 600, a microphone MP, and a speaker SP.

The control unit 200 is a part that performs overall control of various operations of the communication device 100. The control unit 200 includes a CPU, a RAM, a ROM, and the like, and various controls and functions of the communication apparatus 100 are realized by the CPU reading and executing a program stored in the ROM or the like.

[0046] The antenna 400 is a part that transmits a radio wave based on a transmission signal from the transceiver 300, and receives a radio wave from the outside of the communication apparatus 100 and transfers a reception signal to the transceiver 300. is there.

The speaker SP is a part that emits a sound in response to the sound signal from the transceiver 300, and the microphone MP generates a sound signal in response to the reception of the sound and transmits the transceiver via the control unit 200. This is a part that outputs an audio signal to 300. [0048] The operation unit 600 is a part that accepts various inputs from the user to the communication device 100, and includes, for example, various buttons.

[0049] The transceiver 300 converts an audio signal input from the microphone MP through the control unit 200 into a transmission signal and outputs the transmission signal to the antenna 400, while converting a reception signal from the antenna 400 into an audio signal and a speaker. This is the part that outputs to SP.

[0050] In the transceiver 300, an analog audio signal input via the microphone MP force and the control unit 200 is A / D converted (converted from an analog signal to a digital signal) by a DSP (Digital Signal Pr _OCeSSO r) 301. ), The signal is modulated by the modulator 302 and further frequency-converted by the mixer 303 using the oscillation signal of the local oscillator 320. The output of the mixer 303 passes through the transmission band-pass filter 304 and the power amplifier 305, passes through the duplexer 306, and is output as a transmission signal to the antenna 400.

In addition, a received signal from antenna 400 is input to mixer 309 through demultiplexer 306, low noise amplifier 307, and reception bandpass filter 308. The mixer 309 converts the frequency of the received signal using the oscillation signal of the local oscillator 320, the converted signal passes through the low-pass filter 310, is demodulated by the demodulator 311, and is further D / A converted (digital) by the DSP 301. After the signal is converted into an analog signal, it is output as an analog audio signal to the speaker SP via the control unit 200.

[0052] Note that the transmitter / receiver 300 of the communication device 100 is equipped with the duplexer 310 having excellent isolation characteristics, so that a call with less noise is possible. Hereinafter, the duplexer 306 will be described in detail.

[0053] <Demultiplexer>

FIG. 2 is a diagram illustrating a circuit configuration of the duplexer 306 according to the first embodiment of the present invention.

Yes

As shown in FIG. 2, the duplexer 306 includes signal terminals 1 and 2, a common terminal 3, and a transmission filter element.

(Hereinafter simply referred to as “transmission filter”) 4, a reception filter element (hereinafter simply referred to as “reception filter”) 5, a matching circuit 6, and signal lines 7 to 10 are provided.

[0055] The signal terminal 1 is a terminal (transmission side signal terminal) that is electrically connected (conducting connection) to the power amplifier 305 included in the transmission side circuit (transmission circuit). ,Receiver This is a terminal (signal terminal on the receiving side) that is electrically connected to the low noise amplifier 307 included in this circuit (receiving circuit). The common terminal 3 is a terminal that is electrically connected to the antenna 400.

The transmission filter 4 is different from the reception filter 5 in the frequency band (pass frequency band) of the signal that is selectively passed therethrough, and is provided between the common terminal 3 and the transmission-side signal terminal 1. Yes. Specifically, the transmission filter 4 is electrically connected to the transmission-side signal terminal 1 and the common terminal 3 by signal lines 7 and 9. The transmission filter 4 selectively passes a signal in a predetermined transmission frequency band (for example, 824 to 849 MHz) among signals input from the transmission-side signal terminal 1 via the signal line 7, Output to the common terminal 3 via the signal line 9.

The reception filter 5 is provided between the common terminal 3 and the reception-side signal terminal 2. Specifically, the reception filter 5 is electrically connected to the reception-side signal terminal 2 and the common terminal 3 by signal lines 8 and 10. The reception filter 5 selectively selects a signal in a predetermined reception frequency band (for example, 869 to 894 MHz) from signals input from the antenna 400 side, that is, the common terminal 3 through the signal line 10. Pass through and output to the signal terminal 2 on the receiving side via the signal line 8.

The matching circuit 6 is a circuit in which one end is electrically connected to the common terminal 3 and the other end is grounded. A signal in a predetermined reception frequency band is transmitted from the common terminal 3 to the transmission circuit. This is a part that adjusts so that the impedance from the transmitting circuit to the receiving circuit becomes almost infinite while the impedance to the signal becomes almost infinite.

[0059] Here, when transmitting a transmission signal, a matching circuit 6 is provided in front of the common terminal 3 when viewed from the transmission filter 4, and when transmitting a reception signal, it is viewed from the common terminal 3. Thus, a matching circuit 6 is provided in front of the reception filter 5.

In the duplexer 306 having such a circuit configuration, the transmission filter 4 and the reception filter 5 are flip-chip mounted, for example, on a circuit board formed by laminating a plurality of thin dielectric layers. Configured. In addition, the matching line constituting the matching circuit 6 is a spiral conductor pattern (helical pattern) formed in a plurality of dielectric layers or a meandering conductor. It consists of a body pattern (meandering pattern) or both a spiral pattern and a serpentine pattern, and the end is grounded.

Here, the transmission filter 4 and the reception filter 5 may be surface acoustic wave filters (SAW filters), so-called FBAR filters, or other types of filters. . Further, the transmission filter 4 and the reception filter 5 are manufactured on the same substrate (for example, a piezoelectric substrate for the SAW fintoror and various substrates for the FBAR filter), but each is manufactured on a separate substrate. However, it is preferable that they are produced on the same substrate for the following reasons.

[0062] Manufacturing variations occur in each of the transmission filter 4 and the reception filter 5.

For this reason, when the filters 4 and 5 are manufactured on separate substrates, the transmission filter 4 and the reception filter 5 that have various manufacturing variations are combined. As a result, the optimum inductance value S of the conductor pattern (line pattern) of the line of the matching circuit 6 and a problem that varies depending on the combination of the transmission filter 4 and the reception filter 5 are likely to occur. On the other hand, when the filters 4 and 5 are fabricated on the same substrate, similar variations occur between filters fabricated at substantially the same location on the wafer. The optimum inductance value is almost the same for the 5 combinations. Therefore, the transmission filter 4 and the reception filter 5 must be fabricated on the same substrate from the viewpoint that there is no need to worry about characteristic variations due to the combination of the transmission filter 4 and the reception filter 5. Is preferred.

[0063] <Circuit board for duplexer device>

FIG. 3 shows an outline of a substrate 800 on which a circuit for mounting the transmission filter 4 and the reception filter 5 in the duplexer 306 is disposed (hereinafter also referred to as “demultiplexer device circuit substrate”) 800. It is a cross-sectional schematic diagram which illustrates a structure. Note that in Fig. 3 and Fig. 3 and subsequent figures, three XYZ orthogonal axes are attached to clarify the orientation relationship.

[0064] A circuit board for duplexer devices (hereinafter simply referred to as "circuit board") 800 has a predetermined shape.

(Three layers here) dielectric thin film (dielectric layer) Lb, Ld, Lf and the surface of the dielectric layer Lb, Ld, Lf and between the layers A layer (conductor wiring pattern layer) provided with a wiring pattern of four layers of conductors provided La, Lc, Le, and Lg Yes. That is, three dielectric layers Lb, Ld, and Lf are stacked on top of each other, and two conductor wiring pattern layers Lc and Le sandwiched between the plurality of dielectric layers Lb, Ld, and Lf are formed. ing.

[0065] The conductor wiring pattern layer La is the upper surface (the surface in the + Z direction) of the dielectric layer Lb, that is, the circuit board.

It is provided on one main surface (here, the surface) of the multi-layer substrate constituting the 800! /.

[0066] The conductor wiring pattern layer Lc is provided on the lower surface (one Z-direction surface) of the dielectric layer Lb and on the upper surface (+ Z-direction surface) of the dielectric layer Ld. That is, the conductor wiring pattern layer Lc is

The dielectric layer Lb is provided between the dielectric layer Ld and the dielectric layer Ld.

The conductor wiring pattern layer Le is provided on the lower surface (one Z direction surface) of the dielectric layer Ld and on the upper surface (+ Z direction surface) of the dielectric layer Lf. In other words, the conductor wiring pattern layer Le is

The dielectric layer Ld and the dielectric layer Lf are provided between the layers.

[0068] The conductor wiring pattern layer Lg is a lower surface (one Z-direction surface) of the dielectric layer Lf, that is, a circuit board.

It is provided on the other main surface (here, the back surface) of the multilayer substrate constituting 800.

[0069] Thus, the circuit board 800 includes, in order from the top in FIG. 3, the conductor wiring pattern layer La, the dielectric layer Lb, the conductor wiring pattern layer Lc, the dielectric layer Ld, the conductor wiring pattern layer Le, The dielectric layer Lf and the conductor wiring pattern layer Lg are laminated.

[0070] Examples of the dielectric material constituting the dielectric layers Lb, Ld, and Lf include ceramics mainly composed of alumina, glass ceramics that can be sintered at low temperature, or glass epoxy mainly composed of organic materials. Resin or the like is used.

[0071] When ceramics or glass ceramics is used as the dielectric material, a slurry in which a metal oxide such as ceramics and an organic binder are homogeneously kneaded with an organic solvent or the like is first molded into a sheet shape. This produces a plurality of green sheets. Next, a desired conductor pattern (conductor pattern) and a conductor portion (hereinafter simply referred to as “via”) filled with a conductor in a via hole penetrating from the front surface to the back surface are formed on a plurality of green sheets. After that, the circuit board 800 is manufactured by laminating a plurality of green sheets and press-bonding them together and firing them.

[0072] The spiral pattern and the meandering pattern constituting the matching circuit 6 are a plurality of conductor pattern forces produced by a conductor on the surface of each dielectric layer (here, the dielectric layers Ld and Lf). It is formed by being electrically connected by a via provided through the body layer.

Here, silver, an alloy obtained by adding palladium to silver, tungsten, copper, gold, or the like can be used as the conductor constituting the conductor pattern. The conductor pattern is formed by screen printing using a metal conductor or a combination of a film forming method such as vapor deposition or sputtering and etching.

[0074] Conductor patterns that are directly connected to the transmission filter 4 and the reception filter 5 and conductor patterns (terminals) that are connected when a duplexer is mounted on an external circuit such as a PCB. If necessary for improving the bondability with the connection terminals such as the transmission filter 4 and the reception filter 5, the surface of the conductor pattern may be appropriately plated with Ni or Au.

Hereinafter, a specific example of the circuit board 800 will be described.

FIGS. 4 and 5 are diagrams illustrating the arrangement of conductor patterns and vias in each layer La to Lg constituting the circuit board 800. FIG. 4 and 5, the position of the outer edge of the circuit board 800 is indicated by a broken line in order to clarify the positional relationship with the outer edge of the circuit board 800, that is, the outer edges of the dielectric layers Lb, Ld, and Lf. RU

[0077] The multilayer substrate constituting the circuit board 800 has a structure in which three dielectric layers are laminated (three-layer laminated structure), and a conductor pattern (Fig. 4 (a)) formed on the surface of the multilayer substrate. Conductor pattern formed on the back side of the multilayer substrate (Fig. 5 (c)), Conductor pattern formed between the dielectric layer Lb and dielectric layer Ld (Fig. 4 (c)), dielectric layer Ld and dielectric layer A conductor pattern (Fig. 5 (a)) formed between the layer Lf and a plurality of layers penetrating through the dielectric layer Lb for electrically connecting the conductor patterns provided across the dielectric layer Lb. Vias (FIG. 4 (b)), a plurality of vias (FIG. 4 (d)) penetrating through the dielectric layer Ld for electrically connecting conductor patterns provided across the dielectric layer Ld, and A plurality of vias (FIG. 5 (b)) penetrating through the dielectric layer Lf for electrically connecting between the conductor patterns provided across the dielectric layer Lf are provided.

4 and FIG. 5, the transmission and reception filters 4 and 5 are not shown, but the upper surface (the surface in the + Z direction) of the circuit board 800 is the transmission and reception filters 4 and 5. The right side of Fig. 4 (a) is the filter mounting surface of the transmission filter 4, and the left side of Fig. 4 (a) is the filter of the reception filter 5. It becomes a mounting surface! [0079] It should be noted that, in the state of the circuit board 800 alone at the stage before the transmission and reception filters 4 and 5 are mounted and the transmission and reception circuits are connected, the matching circuit 6 has a transmission frequency band different from each other. Lines for adjusting the impedance between the trusted and receiving filters 4 and 5 (hereinafter also referred to as “matching circuit lines”). Each of the signal lines 7 to 10 is a line for transmitting a signal (hereinafter referred to as “line for matching circuit”). Further, the signal terminals 1 and 2 and the common terminal 3 are terminals for transmitting signals (hereinafter also referred to as “signal transmission terminals”).

Here, referring to FIG. 4 and FIG. 5, the connection state of the conductor pattern and the via in the circuit board 800 and the transmission and reception filters 4 and 5 are mounted on the circuit board 800 to transmit and A flow of transmission / reception signals when the reception circuit is connected will be described.

[0081] The signal line 7 composed of the conductor patterns 14, 27, 41 and the vias 19, 32, 46 is electrically connected to the transmission-side signal terminal 1, and the conductor pattern 14 is used for transmission. Filter 4 functions as a terminal to be electrically connected. More specifically, the signal line 7 is surrounded by a plurality of dielectric layers Lb, Ld, Lf except in the vertical direction (the direction along the Y axis), and the plurality of dielectric layers Lb, Ld, Lf A plurality of dielectric layers Lb, Ld, and Lf are formed from the uppermost layer to the lowermost layer so as to penetrate the plurality of dielectric layers Lb, Ld, and Lf in the multilayer substrate thus configured. The transmission signal input from the transmission side signal terminal 1 is input to the transmission filter 4 via the signal line 7.

[0082] Further, the signal line 9 constituted by the conductor patterns 12, 25, 40 and the vias 17, 31, 45 is electrically connected to the common terminal 3, and the conductor pattern 12 is used for transmission. Filter 4 functions as a terminal to be electrically connected. More specifically, the signal line 9 is surrounded by a plurality of dielectric layers Lb, Ld, Lf except in the vertical direction (the direction along the Y axis), and the plurality of dielectric layers Lb, Ld, Lf The uppermost layer force of the plurality of dielectric layers Lb, Ld, and Lf and the lowermost layer are formed so as to penetrate the plurality of dielectric layers Lb, Ld, and Lf inside the multilayer substrate. The transmission signal output from the transmission filter 4 is output to the antenna 400 (FIG. 1) via the signal line 9 and the common terminal 3.

[0083] On the other hand, for the common terminal 3, conductor patterns 15, 25, 40 and vias 20, 31, 45 The configured signal line 10 is electrically connected, and the conductor pattern 15 functions as a terminal to which the reception filter 5 is electrically connected. More specifically, the signal line 10 is surrounded by a plurality of dielectric layers Lb, Ld, Lf except for the upper and lower directions (directions along the Y axis), and the plurality of dielectric layers Lb, Ld, Lf Is formed from the uppermost layer to the lowermost layer of the plurality of dielectric layers Lb, Ld, Lf so as to penetrate through the plurality of dielectric layers Lb, Ld, Lf. The reception signal input from the antenna 400 is input to the reception filter 5 through the common terminal 3 and the signal line 10.

Further, the signal line 8 constituted by the conductor patterns 16, 29, 43 and the vias 21, 36, 48 is electrically connected to the reception side signal terminal 2, and the conductor pattern 16 is The reception filter 5 functions as a terminal to be electrically connected. More specifically, the signal line 8 is surrounded by a plurality of dielectric layers Lb, Ld, Lf except in the vertical direction (the direction along the Y axis), and the plurality of dielectric layers Lb, Ld, Lf Is formed from the top layer to the bottom layer of the plurality of dielectric layers Lb, Ld, and Lf so as to penetrate the plurality of dielectric layers Lb, Ld, and Lf. The signal output from the reception filter 5 is output from the reception-side signal terminal 2 via the signal line 8.

The matching circuit 6 electrically connected to the common terminal 3 is a line including conductor patterns 28 and 40 and vias 34 that are electrically connected to the common terminal 3 by vias 45 (matching lines). It is constituted by. The conductor patterns 28 and 40 constituting the matching circuit 6 are constituted by a spiral pattern. More specifically, the matching circuit 6 is surrounded by a plurality of dielectric layers Lb, Ld, and Lf, and the dielectric layer Ld is formed inside the multilayer substrate constituted by the plurality of dielectric layers Lb, Ld, and Lf. It is formed through. One end of the conductor pattern 28 (the end opposite to the side connected by the spiral pattern 40 and the via 34) is connected to the ground conductor pattern (ground pattern) 44 by the via 35. Electrically connected. Here, “grounding conductor” means “a conductor to which a constant voltage or a reference voltage is applied”.

[0086] The annular electrode pattern 11 included in the conductor spring pattern layer La constituting the uppermost part of the circuit board 800 is composed of a conductor pattern for grounding (grounding) by via groups 22 to 24 each including a plurality of vias. Pattern) 30 is electrically connected. Grounding pattern 30 is formed between a pair of dielectric layers Lb and Ld and is surrounded by two dielectric layers Lb and Ld, and is electrically connected to the grounding pattern 44 by the via groups 37 to 39. Connected. Furthermore, the grounding pattern 44 is formed between a pair of dielectric layers Ld and Lf and is surrounded by two dielectric layers Ld and Lf. The circuit board 800 is formed by via groups 49 to 51. It is electrically connected to a grounding terminal (grounding terminal) 52 provided on the back surface of the.

Note that the line constituted by the conductor patterns 13, 26, 42 and the vias 18, 33, 47 is a line for electrically connecting the transmission filter 4 to the grounding terminal 52.

[0088] On the back surface of the circuit board 800, as shown in FIG. 5 (c), in the conductor wiring pattern layer Lg, the transmission-side signal terminal 1 is arranged on the lower right side in the figure, and the reception-side signal terminal 2 is Arranged at the lower left, the common terminal 3 is arranged at the approximate center in the upper part of the figure. Thus, on the back surface of the circuit board 800, the three terminals 1 to 3 are arranged as far as possible from each other.

[0089] Such a line arrangement includes a signal line 7 (configured by conductor patterns 14, 27, 41 and vias 19, 32, 46) and a matching circuit 6 (configured by conductor patterns 28, 40 and via 34). Between signal line 8 (consisting of conductor patterns 16, 29, 43 and vias 21, 36, 48) and matching circuit 6, signal line 7 and signal line 8 This is to ensure isolation between and. In other words, in a limited space, the distance between the three lines of the matching circuit 6, the signal line 7, and the signal line 8 is devised so that the respective distances are set appropriately.

Further, in the circuit board 800, the signal line 7 and the signal line 8 are surrounded by the grounding patterns 30, 44 from the side.

More specifically, in the plane of the conductor wiring pattern layer Lc (FIG. 4 (c)), the grounding pattern 30 is composed of the conductor pattern 27 constituting the signal line 7 and the conductor constituting the signal line 8. It is provided so as to pass through both the space area between the pattern 29 and the space area between the conductor pattern 27 and the conductor pattern 28 constituting the matching circuit 6, and the conductor pattern 27 from the side. A space area between the conductor pattern 29 and the conductor pattern 27, and a space area between the conductor pattern 29 and the conductor pattern 28, as well as the surrounding annular conductor pattern area (ground pattern area) 30a. Provided to pass through both spatial areas And an annular grounding conductor pattern region (grounding pattern region) 30b surrounding the conductor pattern 29 from the side. Note that the conductor pattern region 30 a is preferably uniform over the entire circumference of the conductor pattern 27. In this case, stray capacitance can be prevented from occurring between the conductor pattern region 30a and the conductor pattern 27. The same configuration is preferable for the relationship between the conductor pattern region 30b and the conductor pattern 29.

[0092] Further, in the plane of the conductor wiring pattern layer Le (Fig. 5 (a)), the grounding pattern 44 includes a conductor pattern 41 constituting the signal line 7 and a conductor pattern 43 constituting the signal line 8. For the grounding of the ring, which is provided so as to pass through both the space area between the space area between the conductor pattern 41 and the conductor pattern 40 constituting the matching circuit 6 and surrounds the conductor pattern 41 from the side. Conductor pattern region (ground pattern region) 44a, and a spatial region between the conductor pattern 43 and the conductor pattern 41 and a spatial region between the conductor pattern 43 and the conductor pattern 40. An annular grounding conductor pattern region (grounding pattern region) 44b is provided so as to pass through the space region and surrounds the conductor pattern 43 from the side.

FIG. 6 is a top view illustrating the configuration of the surface acoustic wave element 900 mounted on the filter mounting surface shown in FIG. 4 (a). Here, the surface acoustic wave element 900 is formed by forming the transmission filter 4 and the reception filter 5 on the same substrate. Note that the inertial surface acoustic wave element 900 shown in FIG. 6 includes a so-called ladder-type filter element.

As shown in FIG. 6, the surface acoustic wave device 900 mainly includes a transmission filter (Tx filter) 4 and a reception filter (Rx filter) 5 on one main surface of the piezoelectric substrate 902! / The elastic surface wave device 900 is provided with an annular electrode portion (annular conductor) 930 that individually surrounds the Tx filter 4 and the Rx filter 5. In FIG. 6, of the two regions surrounded by the annular electrode portion 930, the region where the upper region force Tx filter 4 is provided and the region below the region where the Rx filter 5 is provided are shown.

[0095] The Tx finoleta 4 has a plurality of excitation electrodes composed of six series-arm resonators (series resonators) 914a to 914f and two parallel-arm resonators (parallel resonators) 915a and 915b. Setting Each excitation electrode is electrically connected by a connection electrode 917. The TX filter 4 includes an input pad portion 911, an output pad portion 912 that is electrically connected to the antenna 400, and a ground electrode portion 913. The parallel resonators 915a and 915b are electrically connected to the ground electrode portion 913, respectively.

[0096] On the other hand, the Rx filter 5 is provided with a plurality of excitation electrodes composed of four direct IJ resonators 924a to 924d and four parallel IJ resonators 925a to 925d, and between the excitation electrodes. Are electrically connected by connecting electrode 927. The Rx finoleta 5 is provided with an input pad portion 921, an output pad portion 922, and a grounding electrode 923. The parallel resonators 925a to 925d are electrically connected to the grounding electrode 923, respectively. Has been. Further, the ground electrode 923 is electrically connected to the annular electrode portion 930.

The surface acoustic wave element 900 having such a configuration is mounted on the circuit board 800 by face-down mounting, whereby the duplexer 306 is formed. Specifically, the annular electrode portion 930 is associated with the annular electrode pattern 11, the conductor pattern 14 is associated with the input pad portion 911, the conductor pattern 12 is associated with the output pad portion 912, and the ground electrode portion 913 is associated with. The conductor pattern 13 is electrically connected to the input pad portion 921 via the solder pattern 15 and the conductor pattern 15 is electrically connected to the output pad portion 922 via the solder bump. Here, the parallel resonators 925a to 925d are the grounding electrode 923, the annular electrode portion 930, the solder bump, the annular electrode pattern 11, the via group 22 to 24, the grounding pattern 30, the via group 37 to 39, and the grounding pattern. Are electrically connected (conductively connected) to the grounding terminal 52 through the via 44 and the via groups 49 to 51 sequentially.

As described above, in the circuit board 800 according to the first embodiment, the matching circuit 6 is disposed inside the multilayer board surrounded by the plurality of dielectric layers Lb, Ld, and Lf. Each of the signal line 7 and the signal line 8 is disposed inside the multilayer substrate surrounded by the plurality of dielectric layers Lb, Ld, and Lf, and between the other signal lines 7 and 8 and the matching circuit 6. A grounding conductor (here, grounding pattern areas 30a, 30b, 44a, 44b) is provided that passes through and surrounds the periphery.

[0099] Therefore, between each line in the circuit board 800 (matching circuit 6, signal line 7, and signal line

8 between each line) and the signal lines 7 and 8 and the circuit board. The outside of the plate 800 is also electrically shielded. Therefore, electrical interference inside the circuit board 800 and electrical interference between the outside of the circuit board 800 can be reduced. That is, the isolation characteristics inside the circuit board 800 and the isolation characteristics between the outside of the circuit board 800 can be improved.

[0100] If a configuration in which the grounding conductor surrounding the signal lines 7 and 8 is formed by the conductor pattern formed between the dielectric layers, the grounding conductor can be easily formed. Touch with force S.

Furthermore, since the duplexer 306 on which the circuit board 800 is mounted has excellent isolation characteristics, the communication device 100 on which the duplexer 306 is mounted can perform good communication.

[0102] <Second Embodiment>

In the circuit board 800 according to the first embodiment described above, the signal lines 7 and 8 are surrounded by the grounding patterns 30 and 44. On the other hand, in the circuit board 800A according to the second embodiment, further isolation is provided by providing a via for electrically connecting the grounding patterns 30 and 44 at positions surrounding the signal lines 7 and 8. The characteristics are improved.

[0103] The communication device 100A according to the second embodiment has the same configuration as the communication device 100 according to the first embodiment except that vias are additionally arranged as appropriate. Hereinafter, in the communication device 100A according to the second embodiment, the same parts as those of the communication device 100 according to the first embodiment are denoted by the same reference numerals and the description thereof is omitted, while the communication according to the first embodiment is performed. The configuration of the circuit board 800A different from the device 100 will be mainly described.

FIGS. 7 and 8 are diagrams illustrating the arrangement of conductor patterns and vias in the respective layers La to Lg constituting the circuit board 800A according to the second embodiment.

As shown in FIGS. 7 and 8, in the circuit board 800A, a plurality of vias for grounding are provided around the signal line 7 constituted by the conductor patterns 14, 27, 41 and the vias 19, 32, 46. There are 53a and 53b via groups. In addition, via groups 54a and 54b including a plurality of grounding vias are provided around the signal line 8 constituted by the conductor patterns 16, 29, 43 and the vias 21, 36, 48.

Specifically, as shown in FIG. 7 (d), two annular loops are provided so as to pass between the signal line 7, the signal line 8, and the matching circuit 6, and surround the signal line 7. Grounding pattern Grounding via groups 53a and 53b for electrically connecting the regions 30a and 44a are provided. In addition, two annular grounding pattern regions 30b and 44b that are provided so as to pass between the signal line 8, the signal line 7, and the matching circuit 6 and that surround the signal line 8 are electrically connected. Grounding via groups 54a and 54b are provided.

More specifically, a plurality of annularly arranged in a spatial region between the via 32 constituting the signal line 7 and the via 36 constituting the signal line 8 and the via 34 constituting the matching circuit 6. A grounding via group 53a, 53b is provided. In addition, the via 36 constituting the signal line 8, the via 32 constituting the signal line 7 and the via 34 constituting the matching circuit 6 are constituted by a plurality of vias arranged in a ring shape. Grounding via groups 54a and 54b are provided.

As described above, the circuit board 800A is newly provided with the ground pattern areas 30a, 30b, 44a, and 44b so as to surround the signal lines 7 and 8 with the ground conductors. The ground vias 53a, 53b, 54a and 54b surrounding the signal lines 7 and 8 are newly provided by utilizing the fact that the area where the ground via can be provided is increased. In addition, by providing the ground pattern areas 30a and 30b, via groups 55b, which electrically connect the annular electrode pattern 11 (FIG. 7 (a)) and the conductor pattern 30 (FIG. 7 (c)), 56b (Fig. 7 (b)) Newly installed.

FIG. 9 is a diagram showing an equivalent circuit of the duplexer 306A according to the second embodiment. Here, the ground via group 53a, 53b, 54a, 54b is newly provided, and as shown in FIG. 9, the wiring path (that is, the parallel resonators 925a to 925d of the reception filter 5 are grounded) In the wiring path from the grounding electrode 923 to the grounding terminal 52), the number of wiring paths that are electrically connected in parallel increases. For this reason, the inductance of the wiring path (circuit) from the grounding electrode 923 to the grounding terminal 52 decreases.

[0110] As described above, in the circuit board 800A according to the second embodiment, the periphery of the signal lines 7 and 8 includes a plurality of ground pattern regions 30a, 30b, 44a, which are formed between a plurality of sets of dielectric layers. 44 b and a plurality of ground pattern regions 30a, 30b, 44a, 44b are passed through the dielectric layer Ld sandwiched between them, and the plurality of ground pattern regions 30a, 30b, 44a, 44b are electrically connected. It is surrounded by conductors (here, via groups 53a, 53b, 54a, 54b). [0111] By adopting such a configuration, the circuit board 800A is electrically shielded between the lines inside the circuit board 800A (between the matching circuit 6, the signal line 7 and the signal line 8). And the signal lines 7 and 8 surrounded by the grounding conductor (here, grounding pattern areas 30a, 30b, 44a and 44b, and via groups 53a, 53b, 54a and 54b) are also electrically shielded. The Therefore, electrical interference inside the circuit board and electrical interference between the outside of the circuit board can be further reduced. As a result, the force S can further improve the isolation characteristics inside the circuit board and the isolation characteristics with the outside of the circuit board.

[0112] Further, since the ground pattern areas 30b and 44b are provided around the signal line 8 on the receiving side, the dielectric is provided between the plurality of ground pattern areas 30b and 44b around the signal line 8. The area (position) where a via that is a conductor penetrating the layer Ld can be arranged is increased. Of the reception and transmission filters, a line that electrically connects between the parallel resonator of the filter having a relatively high pass frequency band (generally, the reception filter) and the ground terminal ( In other words, if the inductance value generated in the conductor pattern of the circuit board and vias penetrating the dielectric layer is reduced, the filter having a relatively high pass frequency band in the duplexer is reduced. It is known that there is a property of increasing the out-of-band attenuation on the frequency side.

[0113] According to this property, vias (here, vias) that are conductors that electrically connect the ground patterns 30 and 44 electrically connected to the parallel resonators through the dielectric layer. Group 53a, 53b, 54a, 54b), and by forming a grounding line for via group 53a, 53b, 54a, 54b force parallel lj, parallel resonators 925a-925d and The inductance value with respect to the grounding terminal 52 decreases. For this reason, it is possible to increase the out-of-band attenuation amount of the reception filter 5. That is, it can be said that the fact that the via groups 53a, 53b, 54a, 54b can be newly provided contributes to the reduction of the inductance value.

[0114] Therefore, in the circuit board 800A, by providing a large number of grounding vias so as to surround the signal lines 7 and 8, respectively, the isolation filter is further improved and the reception filter 5 is provided. The communication characteristics of communication apparatus 100A can be further improved by increasing the out-of-band attenuation. [0115] <Modification>

It should be noted that the present invention is not limited to the above-described embodiments, and the gist of the present invention is not deviated from / within the scope of the present invention, and various changes and improvements can be made.

[0116] For example, in the first embodiment, the signal lines 7 and 8 are both surrounded by the ground pattern areas 30a, 30b, 44a, and 44b. Peripheral force of at least one signal line of lines 7 and 8 One or more grounding conductors (for example, conductor pattern regions 30a, 30b) provided between one or more dielectric layers adjacent to each other , 44a, 44b, etc.), the same effects as in the first embodiment can be obtained.

[0117] However, from the viewpoint of further improving the isolation characteristics, the periphery of both of the signal lines 7 and 8 is a plurality of multiple dielectric layers formed between the layers of the adjacent dielectric layers. It is preferable to be surrounded by a grounding conductor (for example, conductor pattern regions 30a, 30b, 44a, 44b).

[0118] In the second embodiment, the ground pattern areas 30a and 44a are electrically connected by the ground via groups 53a and 53b, and the ground pattern areas 30b and 44b are grounded vias. Forces electrically connected by the groups 54a and 54b Not limited to this, so that at least one of the ground pattern areas 30a and 44a and the ground pattern areas 30b and 44b is electrically connected by the via group. Even so, the same effect as in the second embodiment can be obtained.

[0119] However, from the viewpoint of further improving the isolation characteristics and from the viewpoint of further increasing the out-of-band attenuation of the filter, between the ground pattern areas 30a and 44a and between the ground pattern areas 30b and 44b. It is preferable to connect both of them electrically with more vias. Further, when there are four or more dielectric layers constituting the multilayer substrate, they are formed between a plurality of dielectric layers adjacent to each other and surround each signal line 7 and 8. More than one ground pattern area force It is preferable to be electrically connected by more vias.

[0120] In the above embodiment, the signal lines 7 and 8 are surrounded by the annular ground pattern areas 30a, 30b, 44a, and 44b. For the annular ground pattern areas 30a, 30b, 44a, and 44b, As long as electrical connection for grounding can be secured, slits etc. are provided as appropriate. It does not matter.

[0121] The shape of the conductor pattern regions 30a, 30b, 44a, 44b surrounding the signal lines 7, 8 is not necessarily circular, and surrounds the signal line 7 and the signal line 8 and the other signal line 7, As long as the conductor pattern for grounding is provided so as to pass between 8 and the matching circuit 6, those of various shapes can be adopted.

[0122] In the above embodiment, the conductor surrounding the periphery of the signal lines 7 and 8 is constituted by the grounding conductor pattern and via formed between the dielectric layers. However, the present invention is not limited to this. Any grounding conductor that penetrates the dielectric multilayer film may be used.

[0123] In the above embodiment, the matching circuit 6 is not limited to the force S formed by the two layers of the spiral conductor patterns 28, 40. For example, a desired size or inductance value can be obtained. May be composed of one or three or more layers of conductor patterns, etc.

Yes

[0124] Also, in the second embodiment, of the transmission and reception filters 4 and 5, the reception filter 5 has a relatively high pass frequency band. The transmission filter 4 may have a relatively high pass frequency band in accordance with various different standards. At this time, similarly to the reception filter 5 according to the second embodiment, the inductance of the line for electrically connecting the parallel resonator of the transmission filter 4 to the grounding terminal 52 is further reduced. Increase the out-of-band attenuation of the transmission filter 4 with the force S.

[0125] Also, in the second embodiment described above, by reducing the inductance of the line that electrically connects the parallel resonators 925a to 925d of the ladder filter to the ground terminal 52, the out-of-band filter Although an example of increasing the amount of attenuation has been described, the present invention is not limited to this. For example, a filter having a resonator in a parallel arm, such as providing a parallel resonator in a so-called DMS filter, that is, a parallel arm resonator (parallel In the case of a filter having a resonator, the out-of-band attenuation of the filter can be increased by reducing the inductance of the line that electrically connects the parallel resonator to the ground terminal.

Example

[Example] As an example, there are two types having the same configuration as the duplexer 306 using the circuit board 800 according to the first embodiment and the duplexer 306A using the circuit board 800A according to the second embodiment. A duplexer was prepared. A device corresponding to the duplexer 306 was designated as Example 1, and a device corresponding to the duplexer 306A was designated as Example 2.

That is, as the circuit board 800 according to the first embodiment, the matching circuit 6 is disposed inside the multilayer film surrounded by the plurality of dielectric layers, and both the signal lines 7 and 8 are Arranged inside the multilayer film surrounded by a plurality of dielectric layers and surrounded by ground pattern areas 30a, 30b, 44a, 44b passing between the other signal lines 7, 8 and the matching circuit 6. A thing was used.

Further, as the circuit board 800A according to the second embodiment, the matching circuit 6 is disposed inside the multilayer film surrounded by the plurality of dielectric layers, and both of the signal lines 7 and 8 are Ground pattern areas 30a, 30b, 44a, 44b, which are arranged inside a multilayer film surrounded by a plurality of dielectric layers and pass between the other signal lines 7, 8 and the matching circuit 6, and the ground What was surrounded by ground via groups 53a, 53b, 54a, 54b that electrically connect the pattern areas 30a, 30b, 44a, 44b for use was used.

[0129] In the duplexers 306 and 306A, a resonator including an IDT (Inter Digital Transducer) electrode and a reflector electrode on a piezoelectric substrate, a wiring electrode connecting the resonators, and a circuit substrate A surface acoustic wave filter (surface acoustic wave element) 900 (Fig. 6) in which a connection terminal for connection to the substrate was formed was used.

Here, the manufacture of the duplexers 306 and 306A (Examples 1 and 2) using the surface acoustic wave element 900 will be described.

[0131] To manufacture the surface acoustic wave device 900, first, a piezoelectric thin film made of lithium tantalate (LiTaO) was used, and a Ti thin film having a thickness of 6 nm was formed on the main surface of the piezoelectric substrate. An A1-Cu thin film with a thickness of 125 nm was formed on this, and this Ti thin film and A1-Cu thin film were alternately laminated in three layers to form a total of six Ti / Al-Cu laminated films.

[0132] Next, a photoresist having a thickness of about 0.5 m was applied by a resist coating apparatus. Then, using a reduction projection exposure apparatus (stepper) or the like, the photoresist pattern to be the resonator, signal line, pad electrode, etc. shown in FIG. 6 was formed. In the filter for reception The photoresist pattern is also formed in this process for the parallel resonator closest to the antenna. Furthermore, unnecessary portions of the photoresist were dissolved with an alkali developer by a developing device.

[0133] Next, the electrode pattern shown in Fig. 6 was formed by a RIE (Reactive Ion Etching) apparatus. And the protective film was produced on the predetermined area | region of the electrode pattern. Here, an SiO film having a thickness of about 15 nm was formed on the electrode pattern and the main surface of the piezoelectric substrate by a CVD (Chemical Vapor D-marked osition) apparatus.

[0134] Further, the photoresist is patterned by photolithography, and the flip chip electrode portion (input / output electrode, ground electrode and pad electrode) is covered with an RIE apparatus or the like! /, And the S film is etched. went. Then, using a sputtering apparatus, a laminated electrode was formed by laminating a Cr layer, a Ni layer, and an Au layer on the portion from which the SiO film was removed. At this time, the thickness of the laminated electrode was about 1 μm, and the thicknesses of the Cr layer, the Ni layer, and the Au layer were set to 0.01 m, 1 m, and 0.2 m, respectively. Thereafter, unnecessary portions of the photoresist and the laminated electrode were simultaneously removed by a lift-off method, and the portion where the laminated electrode was formed was used as a flip chip electrode portion for electrically connecting the flip chip bump. Then, by dicing along the dicing lines of the piezoelectric substrate, the surface acoustic wave element 900 was divided into chips.

[0135] Regarding the production of the circuit boards 800 and 800A, first, green sheets were produced by molding a slurry in which a metal oxide such as ceramics and an organic binder were homogeneously kneaded with an organic solvent or the like into a sheet. Then, after forming desired conductor patterns and vias on a plurality of green sheets, a plurality of green sheets are laminated and pressure-bonded to produce a multilayer film, and fired to produce a plurality of circuit boards 800. , 800A gathered circuit board (integrated circuit board). The material used for the conductor pattern, etc. provided on the collective circuit board is composed mainly of silver and glass, and has a total of three dielectric layers, conductor patterns formed on the front and back surfaces, and between the layers. An assembled circuit board was prepared.

[0136] Regarding the process of electrically connecting the surface acoustic wave element 900 and the collective circuit board, first, the conductor patterns 11 to 16 of the conductor wiring pattern layer La (Figs. 4 (a) and 7 (a)); A conductive material (conductive material) was printed on top. Solder was used as the conductive material. [0137] Then, the surface acoustic wave element 900 was temporarily bonded to the collective circuit board by a flip chip mounting apparatus with the electrode forming surface of the surface acoustic wave element 900 as the bottom surface. This temporary bonding was performed in an N gas atmosphere. Further, by performing reflow in an N gas atmosphere and melting the solder, the surface acoustic wave element 900 and the collective circuit board were bonded and hermetically sealed.

[0138] Then, a resin was applied to the collective circuit board to which the surface acoustic wave element 900 was bonded, and beta was performed in an N gas atmosphere, thereby sealing the surface acoustic wave element 900 with the resin.

Here, since the collective circuit board on which a plurality of surface acoustic wave elements 900 can be mounted is used, the circuit board is divided into individual pieces of the circuit boards 800 and 800A by performing dicing along the dicing lines of the collective circuit board. Thus, a plurality of duplexers 306 and 306A were obtained in one step. The dimensions (finished dimensions) of the completed duplexers 306 and 306A were set to a mounting area of 2.5 mm X 2. Omm X height of 0.9 mm.

[0140] For the two types of demultiplexers 306 and 306A fabricated in this way, the transmission coefficient from the transmission side signal terminal 1 to the reception side signal terminal 2 based on the measured value (S parameter) using a network analyzer ( That is, isolation was obtained.

[0141] (Comparative example)

On the other hand, as a comparative example, branching using a circuit board in which the ground pattern areas 30a, 30b, 44a, and 44b surrounding both signal lines 7 and 8 are deleted from the circuit board 800 according to the first embodiment. A vessel was adopted. In other words, as a comparative example, a duplexer was used in which both signal lines 7 and 8 were not surrounded by grounding vias or grounding vias.

FIG. 10 and FIG. 11 are diagrams showing the arrangement of conductor patterns and vias in each layer La to Lg constituting the circuit board included in the duplexer according to the comparative example.

[0143] As shown in FIG. 10 (c), in the conductor wiring pattern layer Lc according to the modified example, the signal lines 7 and 8 are respectively surrounded from the conductor pattern of the conductor wiring pattern layer Lc according to the first embodiment. The grounding pattern areas 30a and 30b are removed, and the grounding conductor pattern 30 is separated into three grounding conductor patterns 55 to 57.

Further, as shown in FIG. 11 (a), in the conductor arrangement pattern layer Le according to the modified example, the signal lines 7 and 8 are respectively surrounded by the conductor pattern of the conductor wiring pattern layer Le according to the first embodiment. The ring-shaped grounding pattern areas 44a and 44b were removed, and the grounding conductor pattern 44 is separated into three grounding conductor patterns 58-60.

[0145] Except for these feature points, the circuit board according to the modified example has the same configuration as the circuit board 800 according to the first embodiment. Therefore, in FIGS. Parts similar to those of the circuit board 800 according to FIG.

Further, the duplexer according to the modification is similar to the duplexer according to the first and second embodiments.

900, and the manufacturing method of the duplexer is described in the first embodiment.

, 2 are the same as those of the duplexer according to FIG.

[0147] As with the duplexers 306 and 306A according to the first and second embodiments, the duplexer according to the modified example manufactured in this way is transmitted from the measured value (S parameter) using the network analyzer. The transmission coefficient (ie isolation) from the side signal terminal 1 to the reception side signal terminal 2 was obtained.

[0148] (Comparison of Examples and Comparative Examples)

Transmission coefficients from the transmission-side signal terminal 1 to the reception-side signal terminal 2 for the two types of duplexers according to Examples 1 and 2 and the duplexer according to the comparative example obtained as described above. (In other words, isolation) is shown in FIGS. 12 to 14 and Table 1 below. 12 to 14, the horizontal axis represents frequency (unit: MHz), and the vertical axis represents isolation (unit: dB). The isolation of Example 1 is indicated by a solid line R1, the isolation of Example 2 is indicated by a thick line R2, and the isolation of the comparative example is indicated by a broken line R3. Fig. 12 shows the isolation in a wide frequency band (760 to 960MHz). Fig. 13 shows the isolation focused on the transmission frequency band (824 to 849 MHz) required in the US-CDMA system, that is, the isolation focused on the area surrounded by the thick broken line A1 in Fig. 12. ing. Fig. 14 shows the isolation focused on the reception frequency band (869 to 894 MHz) required in the US-CDMA system, that is, the isolation focused on the area surrounded by the thick broken line A2 in Fig. 12. . In Table 1 below, the maximum value of isolation in the transmission frequency band (824 to 849 MHz) and the reception frequency band (869 to 894 MHz) for Examples 1, 2 and Comparative Example are shown. The maximum isolation values are shown respectively.

[0149] [Table 1] Example 1 Example 2 Comparative Example Zhou Yu (MH z)

—56 —5 r -53 824-849 isole ”5 / yong (d B)

-41 -42 -42 869—894

[0150] In the branching filter of the comparative example in which the ground pattern areas 30a, 30b, 44a, 44b and the via groups 53a, 53b, 54a, 54b surrounding both the signal lines 7 and 8 are not provided, The maximum isolation value in the transmission frequency band (824 to 849 MHz) was -53 dB, and the maximum isolation value in the reception frequency band (869 to 894 MHz) was -42 dB.

[0151] On the other hand, in the duplexer of Example 1 in which the grounding pattern regions 30a, 30b, 44a, 44b surrounding the both sides of the signal lines 7, 8 are provided, compared with the comparative example, The maximum isolation value in the frequency band (86 9 to 894 MHz) was almost unchanged at 41 dB. The maximum isolation value in the frequency band for transmission (824 to 849 MHz) was reduced to -56 dB, and the frequency of transmission and reception. The isolation characteristics improved as a whole band. Considering the importance of improving isolation in the frequency band for transmission, especially for communication devices, because the output of the transmission signal is higher (higher power) than the received signal. Then, compared to the comparative example, in Example 1, the maximum value of isolation in the transmission frequency band (824 to 849 MHz) is reduced by 3 dB, and the isolation characteristics that greatly contribute to the improvement of communication characteristics It can be said that it has improved.

[0152] In addition to the duplexer of the first embodiment, the demultiplexing of the second embodiment in which grounding via groups 53a, 53b, 54a, and 54b surrounding both the signal lines 7 and 8 are further provided. In comparison with the comparative example, the maximum isolation value in the receiving frequency band (869 to 894 MHz) is a force that does not change as much as -42 dB, and the combined force is the isolation in the transmitting frequency band (824 to 849 MHz). The maximum value of was reduced to 57dB. In the second embodiment, as compared with the first embodiment, both the transmission frequency band (824 to 849 MHz) and the reception frequency band (869 to 894 MHz) are! / The maximum value tended to decrease slightly. That is, by providing grounding via groups 53a, 53b, 54a, 54b surrounding both signal lines 7 and 8, the isolation characteristics can be further improved. Based on the above results, both signal lines 7 and 8 are arranged inside a plurality of dielectric layers, and the periphery of both signal lines 7 and 8 is connected to the other signal lines 7 and 8 and matching circuit 6. It was confirmed that a duplexer with improved isolation characteristics can be obtained by surrounding it with a grounding conductor that passes between them. Further, the isolation characteristics tend to be further improved by surrounding the signal lines 7 and 8 with grounding via groups rather than surrounding them with grounding patterns provided between the dielectric layers. I confirmed it.

Claims

The scope of the claims

[1] a plurality of dielectric layers stacked on each other;

A matching circuit line for adjusting impedance between the first and second filter elements surrounded by the plurality of dielectric layers and having mutually different pass frequency bands;

The first filter element and the first signal transmission terminal are electrically surrounded by the plurality of dielectric layers and formed from the uppermost layer to the lowermost layer of the plurality of dielectric layers. A first signal transmission line for connection to

A second signal transmission line for electrically connecting the second filter element and the second signal transmission terminal;

Provided between the first signal transmission line and the matching circuit line, and between the first signal transmission line and the second signal transmission line, and the first signal. A first grounding conductor surrounding the transmission line;

A circuit board for a duplexer device, comprising:

[2] A circuit board for a duplexer device according to claim 1,

The second signal transmission line is

Surrounded by the plurality of dielectric layers and formed from an uppermost layer to a lowermost layer of the plurality of dielectric layers;

The circuit board for the duplexer device,

Provided between the second signal transmission line and the matching circuit line, and between the second signal transmission line and the first signal transmission line, and the second signal. A second grounding conductor surrounding the transmission line,

A circuit board for a duplexer device, further comprising:

[3] A circuit board for a duplexer device according to claim 1,

The first grounding conductor is

A circuit board for a duplexer device, comprising a conductor pattern formed between one or more pairs of dielectric layers adjacent to each other among the plurality of dielectric layers.

[4] A circuit board for a duplexer device according to claim 3, The first grounding conductor is

A plurality of conductor pattern regions formed between layers of a plurality of dielectric layers adjacent to each other among the plurality of dielectric layers, and a dielectric layer sandwiched between the plurality of conductor pattern regions. And one or more conductors that electrically connect the plurality of conductor pattern regions to each other; and

A circuit board for a duplexer device, comprising:

[5] A circuit board for a duplexer device according to claim 4,

The one or more conductors are

A circuit board for a duplexer device, comprising a plurality of conductors provided so as to surround the first signal transmission line.

[6] The circuit board for a duplexer device according to claim 1,

The first and second filter elements are:

A circuit board for a duplexer device, wherein each is a ladder type filter element.

[7] The circuit board for a duplexer device according to claim 4,

The filter element having a relatively high pass frequency band among the first and second filter elements has a resonator in a parallel arm,

The resonator is

A duplexer device circuit board, wherein the duplexer device circuit board is electrically connected to the first grounding conductor.

[8] A circuit board for a duplexer device according to claim 2,

The first and second grounding conductors are

[9] The circuit board for a duplexer device according to claim 8,

The first grounding conductor is

A plurality of first conductor pattern regions respectively formed between layers of a plurality of dielectric layers adjacent to each other among the plurality of dielectric layers; and the plurality of first conductor pattern regions. One or more conductors penetrating through the dielectric layer sandwiched between the regions and electrically connecting the plurality of first conductor pattern regions to each other;

Including

The second grounding conductor is

A plurality of second conductor pattern regions formed between layers of a plurality of dielectric layers adjacent to each other among the plurality of dielectric layers, and sandwiched between the plurality of second conductor pattern regions. One or more conductors penetrating the dielectric layer and electrically connecting the plurality of second conductor pattern regions to each other;

A circuit board for a duplexer device, comprising:

[10] The circuit board for a duplexer device according to claim 9,

One or more conductors that electrically connect the plurality of first conductor pattern regions to each other include a plurality of conductors provided so as to surround the first signal transmission line. Circuit board for instrument devices.

[11] The circuit board for a duplexer device according to claim 9,

One or more conductors that electrically connect the plurality of second conductor pattern regions to each other include a plurality of conductors provided so as to surround the second signal transmission line. Circuit board for instrument devices.

[12] The circuit board for a duplexer device according to claim 9,

The first and second filter elements are:

[13] The circuit board for a duplexer device according to claim 9,

The resonator is

A circuit board for a duplexer device, wherein the circuit board is electrically connected to the first and second grounding conductors.

[14] The circuit board for a duplexer device according to claim 1, The first filter element is a transmission filter element;

The duplexer device circuit board, wherein the second filter element is a reception filter element.

[15] The circuit board for the duplexer device according to any one of claims 1 to 14, and the first and second filter elements mounted on the circuit board for the duplexer device. ,

A duplexer comprising:

[16] The duplexer according to claim 15,

The first filter element is a transmission filter element;

The second filter element is a receiving filter element;

The first and second filter elements are electrically connected in common to a common terminal electrically connected to an antenna;

One end of the matching circuit is electrically joined to the common terminal,

A duplexer characterized in that the other end of the matching circuit different from one end of the matching circuit is grounded! /.

[17] The duplexer according to claim 16,

The matching circuit has an almost infinite impedance from the common terminal to the transmission circuit for a signal in a predetermined reception frequency band, and an impedance from the transmission circuit to the reception circuit for a signal in a predetermined transmission frequency band. A demultiplexer characterized in that is almost infinite.

[18] The duplexer according to claim 17,

The frequency band power ^s for reception is 869 to 894 MHz,

The duplexer characterized in that the frequency band for transmission is 824 to 849 MHz.

[19] A duplexer according to claim 15,

The duplexer, wherein the first and second filter elements are each surrounded by an annular electrode portion.

[20] A printing-S apparatus comprising the duplexer according to any one of claims 15 to 19.