JP2005109950A - Resonator and dielectric filter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resonator and a dielectric filter which can attain miniaturization and low cost, has high accuracy and low loss, and has desired characteristics. <P>SOLUTION: Open stubs 191a-s, 191b-s are provided on a pair of parallel resonance electrodes 191a, 191b so as to protrude toward another resonance electrode side to adjust an input impedance, thereby eliminating the necessity of a matching circuit. The first capacitor of a laminated structure consisting of an electrode 172a connected to a ground layer 12, an electrode 192a connected to the open end side of the resonance electrode 191a, and a dielectric layer 18 is provided. Further, a second capacitor of a laminated structure consisting of an electrode 172b connected to the layer 12, an electrode 192b connected to the open end side of the resonance electrode 191b, and the dielectric layer 18 is provided. Thus, the desired characteristics can be acquired even if the length of the resonance electrode is short. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a resonator and a dielectric filter. Specifically, an open stub is provided on the resonance electrode so as to protrude toward the other resonance electrode.

With the spread of communication systems using high frequency radio waves in the microwave band and millimeter wave band, for example, telephone systems such as mobile phones and wireless LAN (local area network) systems,
Various data can be easily transmitted and received in various places such as home and outdoors without using a relay device or the like.

  Such devices used in the communication system are provided with filter elements such as a low-pass filter (LPF), a high-pass filter (HPF), and a band-pass filter (BPF). This filter element is designed not as a lumped constant circuit but as a distributed constant circuit in order to process a signal in a high frequency band. For example, as shown in Patent Document 1, a triplate structure filter is formed using a pair of parallel conductor patterns.

  In addition, miniaturization by high-density mounting, multilayering of substrates, and the like has been achieved so that devices can be easily carried. For example, as shown in Patent Document 2, when a pattern wiring layer, a dielectric insulating layer, or the like is multilayered, a layer in which a filter, a capacitor, an inductor, a resistor, or the like is formed, a pattern layer for signal wiring, power supply, or the like is provided. A high-frequency module device is made by multilayering.

JP 2000-252716 A JP2002-334806

  By the way, when using a signal in a high frequency band, if impedance matching is not achieved between circuits, reflection occurs and loss increases. For this reason, a matching circuit for matching impedance between circuits is required. However, if a matching circuit is provided, a board space for the matching circuit is required, which is an obstacle to miniaturization.

  Further, in a comb line type filter that electromagnetically couples a pair of conductor patterns having a length of ¼ wavelength of a signal to be passed, if the frequency of the signal to be passed is low, the length of the conductor pattern must be increased. This makes it impossible to reduce the size of the filter.

  Furthermore, when the filter layer designed as a distributed constant circuit and the pattern wiring layer are multi-layered to reduce the size of the device, the filter is affected by the signal wiring pattern, etc., and the desired filter characteristics cannot be obtained. Will occur. That is, if a signal wiring pattern is provided between the ground conductor layer and the conductor pattern of Patent Document 1, the electromagnetic coupling state of the pair of parallel conductor patterns may change, and desired filter characteristics may not be obtained. Occurs.

  Accordingly, the present invention provides a resonator and a dielectric filter having desired characteristics that can be reduced in size and cost, and have high accuracy and low loss.

  In the resonator according to the present invention, a ground conductor layer is formed on one surface side of a multilayer substrate formed by laminating a plurality of dielectric layers and conductor layers, and one end is a short-circuit end connected to the ground conductor layer. A resonance pattern conductor layer having a pair of parallel resonance electrodes with the other end being an open end is provided to face the ground conductor layer with the dielectric layer interposed therebetween, and the open end side of one of the resonance electrodes is In the resonator that is used as a signal input terminal and the open end side of the other resonance electrode is used as a signal output terminal, an open stub is protruded from the resonance electrode to the other resonance electrode side.

  In the dielectric filter according to the present invention, a ground conductor layer is formed on one surface side of a multilayer substrate formed by laminating a plurality of dielectric layers and conductor layers, and one end is connected to the ground conductor layer. A resonance pattern conductor layer having a pair of parallel resonance electrodes, the other end of which is a short-circuited end and an open end, is provided to face the ground conductor layer through the dielectric layer, and one of the resonance electrodes is opened. The end side is used as a signal input terminal, the open end side of the other resonance electrode is used as a signal output terminal, a signal in a desired frequency band is passed from the signal input to the signal input terminal, and the signal output terminal In the output dielectric filter, an open stub is provided on the resonance electrode so as to protrude toward the other resonance electrode.

  In the present invention, open stubs are provided so as to protrude from each other in a pair of parallel resonance electrodes. Also, a first capacitor having a laminated structure in which one terminal is connected to a ground conductor layer and the other terminal is connected to a signal input terminal or a resonance electrode using the open end side as a signal input terminal, or one terminal is grounded A second capacitor with a laminated structure connected to the conductor layer and connected to the resonance electrode using the other terminal as a signal output terminal or the open end side as a signal output terminal, and one terminal as a signal input terminal or open end side as a signal A third capacitor having a multilayer structure in which the other terminal is connected to the resonance electrode used as the input terminal and the other terminal is connected to the resonance electrode using the open end side as the signal output terminal is formed using, for example, tantalum oxide. The Furthermore, an open stub is provided at the terminal connection position of the first and second capacitors in the resonance electrode. Furthermore, a slot is formed in the conductor layer located between the ground conductor layer and the resonance pattern conductor layer so as to include a region facing the resonance electrode.

  According to the present invention, since the open stub is provided on the resonance electrode so as to protrude to the other resonance electrode, the input impedance and the output impedance can be varied by adjusting the size of the open stub, and the matching circuit It is not necessary to provide a separate filter, and the apparatus using the resonator and the dielectric filter can be downsized. In addition, since the number of parts can be reduced, the apparatus can be configured at low cost.

  Also, a first capacitor having a laminated structure in which one terminal is connected to a ground conductor layer and the other terminal is connected to a signal input terminal or a resonance electrode using the open end side as a signal input terminal, or one terminal is grounded A second capacitor having a multilayer structure is provided which is connected to the conductor layer and connected to the resonance electrode using the other terminal as the signal output terminal or the open end side as the signal output terminal, so that the length of the resonance electrode is passed. The wavelength can be shorter than the signal wavelength, and the device can be further miniaturized. Further, since the open stub is provided at the terminal connection position of the first and second capacitors in the resonance electrode, the influence of the electromagnetic field can be concentrated. Furthermore, one terminal is connected to a resonance electrode that uses the signal input terminal or the open end side as a signal input terminal, and the other terminal is connected to a resonance electrode that uses the signal output terminal or the open end side as a signal output terminal. Since the third capacitor having the structure is provided, the trapping frequency can be adjusted by adjusting the capacitance of the third capacitor. Furthermore, by using a tantalum oxide capacitor, it is possible to reduce the area occupied by the substrate of the capacitor, and the device can be further miniaturized. In addition, since a slot is formed in the conductor layer located between the ground conductor layer and the resonance pattern conductor layer so as to include a region facing the resonance electrode, without being affected by other signal wiring patterns, A resonator or a dielectric filter having desired characteristics can be obtained.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a plan view showing a configuration of a dielectric filter 10 of the present invention, FIG. 2 is a schematic cross-sectional view of the dielectric filter 10 shown in FIG. 1 at the position AA ′, and FIG. 3 is an exploded perspective view of the dielectric filter 10. The figure is shown. A first conductor layer 12 as a ground conductor layer is formed on the back side of the multilayer substrate 11 on which a plurality of dielectric layers and conductor layers are laminated. For example, on the surface layer side of the multilayer substrate 11 facing the first conductor layer 12 through the dielectric layer, the resonance electrodes 191a and 191b, the capacitor electrodes 192a and 192b, and the signal input terminal 193a are opposed to the first conductor layer 12. The fourth conductor layer 19 is formed as a resonance pattern conductor layer composed of a conductor pattern having a signal output terminal 193b and a ground electrode 194 and a conductor pattern to be the ground electrode 195.

  The resonance electrode 191a and the resonance electrode 191b are formed so as to be substantially parallel to each other at a predetermined interval from each other. One end of each of the resonance electrodes 191a and 191b is connected to the ground electrode 194, and the other is an open end. A signal input terminal 193a is provided on the open end side of the resonance electrode 191a in a direction substantially orthogonal to the resonance electrode 191a. Similarly, a signal output terminal 193b is provided on the open end side of the resonance electrode 191b. Further, an open stub 191a-s is provided on the resonance electrode 191a so as to protrude toward the resonance electrode 191b, and an open stub 191b-s is provided on the resonance electrode 191b so as to protrude toward the resonance electrode 191a.

  A capacitor electrode 192a projecting from the resonance electrode 191a is formed at a position opposite to the open stub 191a-s formation side of the resonance electrode 191a. In addition, a capacitor electrode 192b protruding from the resonance electrode 191b is formed at a position opposite to the open stub 191b-s formation side of the resonance electrode 191b. Furthermore, the third conductor layer 17 is provided so as to face the fourth conductor layer 19 in parallel with the fourth dielectric layer 18 interposed therebetween.

  The third conductor layer 17 includes a conductor pattern in which the capacitor electrodes 172a and 172b are connected to the ground electrode 174, a conductor pattern to be the capacitor electrode 173, and a conductor pattern to be the ground electrode 175. The capacitor electrode 172a is formed to face the capacitor electrode 192a. The capacitor electrode 192a, the fourth dielectric layer 18, and the capacitor electrode 172a constitute a capacitor C1. The capacitor electrode 172b is formed to face the capacitor electrode 192b. The capacitor electrode 192b, the fourth dielectric layer 18, and the capacitor electrode 172b constitute a capacitor C2. Further, the ground electrode 174 has the same shape as the ground electrode 194 so that the region facing the resonance electrodes 191a and 191b is a slot.

  The resonant electrode 191a is connected to the capacitor electrode 173 through a conductor layer connecting portion (hereinafter simply referred to as “via”) 20 such as a via hole or a through hole. The capacitor electrode 173 is formed so as to face the pattern surface of the resonance electrode 191b through the fourth dielectric layer 18 made of a dielectric material, and the capacitor C3 is configured by the capacitor electrode 173 and the resonance electrode 191b. To do. Further, the first conductor layer 12, the ground electrodes 174, 175, 194, 195 and the second conductor layer 14 are electrically connected by the via 21.

  The first dielectric layer 13 is a layer serving as a base of the multilayer substrate 11. The first conductor layer 12 is formed on one surface side of the first dielectric layer 13, and the second conductor layer 14 is formed on the opposite surface side. Form. In the second conductor layer 14, a slot is formed so as to include a region facing the resonance electrodes 191a and 191b, and the second dielectric layer 15 is provided in this slot.

  Thus, by providing the slot, since no other conductor layer is provided between the resonance electrodes 191a and 191b and the first conductor layer 12, the electromagnetic coupling state of the pair of parallel resonance electrodes 191a and 191b. Is not changed by other conductor layers.

  FIG. 4 shows an equivalent circuit of the dielectric filter 10. In this dielectric filter 10, a circuit PRa is configured by connecting a capacitor C1 in parallel to a parallel circuit of an inductance La of a resonance electrode 191a provided with an open stub 191a-s and a stray capacitance Ca. In addition, a circuit PRb is configured by connecting a capacitor C2 in parallel to a parallel circuit of the inductance Lb of the resonant electrode 191b and the stray capacitance Cb provided with the open stub 191b-s. The circuit PRa and the circuit PRb are capacitively coupled through the capacitor C3. For this reason, if the longitudinal lengths of the resonance electrodes 191a and 191b and the capacitances of the capacitors C1, C2 and C3 are adjusted, when the high frequency signal RFin is input from the signal input terminal 193a, the high frequency signal RFin is filtered. Thus, a signal through which a signal in a desired frequency band is passed can be taken out from the signal output terminal 193b. Further, by adjusting the impedance by changing the length of the open stubs 191a-s, 191b-s (the length protruding from the resonant electrodes 191a, 191b), the transmission lines can be matched without providing a matching circuit. Can do. Further, by matching the formation positions of the open stubs 191a-s and 191b-s with the capacitor electrodes, it is possible to concentrate the influence of the electromagnetic field due to the provision of the open stubs and the capacitor electrodes. For this reason, impedance deviation and loss can be reduced as compared with the case where the open stub and the capacitor electrode are formed at different positions in the longitudinal direction of the resonance electrode.

  In the dielectric filter 10, when the capacitances of the capacitors C1 and C2 are increased, the resonance frequency of the resonator configured using the resonance electrodes 191a and 191b can be moved to the low frequency side. That is, the pass band of the dielectric filter 10 can be moved to the low frequency side. Further, the resonance frequency can be moved to the high frequency side by reducing the capacitance of the capacitors C1 and C2. That is, the pass band of the dielectric filter 10 can be moved to the high frequency side.

  Further, the capacitor C3 functions as a trap. By increasing the capacitance of the capacitor C3, the trapping frequency (notch point) can be moved to the low frequency side, and by reducing the capacitance of the capacitor C3. The notch point can be moved to the high frequency side.

  Next, a procedure for generating a dielectric filter will be described with reference to an exploded perspective view shown in FIG. The dielectric filter 10 uses a so-called printed wiring board as a base substrate. For example, a printed wiring board in which a conductor layer is provided on both surfaces of a dielectric substrate is used as the base substrate.

  One conductor layer of the base substrate is a first conductor layer 12, and the other conductor layer is a second conductor layer 14. The first conductor layer 12 and the second conductor layer 14 are electrically connected by a via 21 made of, for example, copper. The via 21 is formed in a part of the dielectric substrate by drilling, laser processing, plasma etching processing or the like through the dielectric substrate. A conductive film made of copper can be formed in the hole thus formed by via plating, for example, electrolytic plating using a copper sulfate solution.

  The dielectric substrate corresponds to the first dielectric layer 13 and is preferably formed of a material with low dielectric loss (low tan δ), that is, a material excellent in high frequency characteristics. Examples of such materials include organic materials such as polyphenylethylene (PPE), bismaleidotriazine (BT-resin), polytetrafluoroethylene, polyimide, liquid crystal polymer (LCP), polynorbornene (PNB), and ceramics. Or the mixed material of a ceramic and an organic material etc. can be mentioned. The first dielectric layer 13 is preferably formed of a material having heat resistance and chemical resistance in addition to the materials described above, and an inexpensive epoxy substrate is used as a dielectric substrate made of such a material. FR-5 etc. can be mentioned. Thus, by using an inexpensive organic material as the first dielectric layer 13, the cost can be reduced as compared with the case of using a relatively expensive Si substrate or glass substrate as in the past. ing.

  A slot is formed in the second conductor layer 14 so as to include a region facing the resonance electrodes 191a and 191b. For example, the conductor in the slot portion is removed using an etching method.

  An insulating film using an insulating material having a high dielectric constant, such as an epoxy resin, is formed on the second conductor layer 14 in which the slots are formed. Note that the insulating film may be formed on both surfaces of the base substrate. In this case, the first conductor layer 12 can be protected by the insulating film formed on the first conductor layer 12. After the insulating film is formed, the insulating film formed on the second conductor layer 14 is polished until the second conductor layer 14 is exposed. As a result, the second dielectric layer 15 can be formed, and the step between the second conductor layer 14 and the second dielectric layer 15 can be eliminated, and a planarized surface used as a build-up formation surface can be formed.

  A third dielectric layer 16 is laminated on the buildup formation surface, and a capacitor and a resonance electrode are formed on the third dielectric layer 16 by a thin film formation technique or a thick film formation technique. The third dielectric layer 16 is preferably formed of a material having a low dielectric loss (low tan δ), that is, an organic material having excellent high frequency characteristics, and is formed of an organic material having heat resistance and chemical resistance. It is preferable that Examples of such an organic material include benzocyclbutene (BCB), polyimide, polynorbornene (PNB), liquid crystal polymer (LCP), epoxy resin, and acrylic resin. The third dielectric layer 16 is made of such an organic material using a method excellent in coating uniformity and film thickness control, such as spin coating, curtain coating, roll coating, dip coating, or the like. It can be formed with high accuracy on the build-up forming surface.

  Next, a conductive film made of, for example, nickel or copper is formed on the third dielectric layer 16 over the entire surface. Thereafter, as described above, a conductor pattern of the third conductor layer 17 is formed by using a photolithography technique. That is, by etching this conductive film using a photoresist patterned in a predetermined shape as a mask, a conductor pattern having capacitor electrodes 172a and 172b, a conductor pattern serving as capacitor electrode 173, and a conductor serving as ground electrode 175 are used. Form a pattern. Capacitor electrodes 172a, 172b, and 173 and a ground electrode 175 are formed by forming and etching a conductive film made of copper having a thickness of about several μm, for example, by electrolytic plating using a copper sulfate solution. Also, vias 21 are provided in the third dielectric layer 16 to connect the second conductor layer 14 to the capacitor electrodes 172a and 172b and the ground electrode 175.

  After the fourth dielectric layer 18 made of the above-described organic material is formed on the third dielectric layer 16 on which the capacitor electrodes 172a, 172b, 173 and the ground electrode 175 are formed, a conductive film made of, for example, nickel or copper Is formed over the entire surface. After that, using the photolithography technique as described above, the conductor pattern including the resonance electrodes 191a and 191b, the capacitor electrodes 192a and 192b, the signal input terminal 193a, the signal output terminal 193b, and the ground electrode 194 and the ground electrode 195 is used. Form a pattern. Also, vias 21 are provided in the fourth dielectric layer 18, the capacitor electrodes 172 a and 172 b of the third conductor layer 17 are connected to the ground electrode 194 of the fourth conductor layer 19, and the ground electrode 175 of the third conductor layer 17 is connected to the ground electrode 175 of the third conductor layer 17. The ground electrode 195 of the fourth conductor layer 19 is connected.

  As described above, by using the thin film patterning technique, the wiring width and the wiring interval of the resonance electrode can be made thinner than the conventional one. For example, the thickness of the electrode or dielectric layer can be reduced to about 10 μm to 30 μm, the wiring width of the resonance electrode can be set to about 5 μm to 20 μm, and the interval between the resonance electrodes can be set to about 5 μm to 20 μm. Therefore, the self-inductance and mutual inductance M of the resonator are increased, and the wiring length of the resonant electrode can be shortened. That is, the dielectric filter can be reduced in size. In addition, since a capacitor is added between the resonance electrode and the ground electrode, the pass band can be adjusted to a desired frequency by adjusting the capacitance of the capacitor. Furthermore, since a trap can be inserted by adjusting a capacitor provided between the resonant electrodes, it is possible to adjust the stop band frequency of the dielectric filter.

  In addition, since the multilayer substrate is formed using a thin film, the dielectric filter can be thinned. For example, a base substrate having a thickness of about 200 μm to 800 μm is used, and a built-up formation surface is provided on the base substrate. Furthermore, a conductor layer or a dielectric layer is laminated on the build-up formation surface to form a laminated substrate having a thickness of about 10 μm to 30 μm on which a resonance electrode and a capacitor are formed, thereby reducing the thickness of the dielectric. A body filter can be constructed.

  By the way, there is a correlation between the wiring length of the resonance electrode and the capacitance of the capacitor, and if the wiring length of the resonance electrode is shortened, a capacitor having a large capacitance is required. Therefore, if a capacitor having a large capacitance with respect to the occupied area on the substrate is used, the dielectric filter can be further downsized.

Next, a case where a capacitor having a larger capacitance with respect to the occupied area than a capacitor using the fourth dielectric layer 18 is described. FIG. 5 shows another configuration of the dielectric filter. As the capacitor, for example, a tantalum oxide capacitor using tantalum oxide (Ta ₂ O ₅ ) as a dielectric is used. FIG. 6 is a partial sectional schematic view of the tantalum oxide capacitor portion (BB ′ position in FIG. 5).

In the tantalum oxide capacitor, a tantalum nitride (TaN) film 17u is formed on capacitor electrodes 172a, 172b, and 173 which are one electrode. The tantalum nitride film 17u can be formed by CVD (Chemical Vapor Deposition), sputtering or vapor deposition. The surface layer portion of the tantalum nitride film 17u is anodized to form a tantalum oxide (Ta ₂ O ₅ ) film 17t which is a high dielectric constant and low loss high dielectric material. Further, a wiring film 17s to be the other electrode of the tantalum oxide capacitor is formed on the tantalum oxide film, and this wiring film 17s is connected to the capacitor electrodes 192a and 192b and the resonance electrode 191b. For the connection between the wiring film 17s, the capacitor electrodes 192a and 192b, and the resonance electrode 191b, for example, the above-described fourth dielectric layer 18 is formed after the wiring film is formed, and vias 20 and 21 are formed in the fourth dielectric layer 18. In this case, the via 22 for connecting the wiring film, the capacitor electrodes 192a and 192b, and the resonance electrode 191b may be provided.

  When a tantalum oxide capacitor is used as the capacitor, the area occupied when obtaining the same capacitance is reduced compared to the case where the capacitor is formed using the fourth dielectric layer 18, so the dielectric filter is downsized. it can. Furthermore, when the capacitor is used in a high frequency region, it causes self-resonance due to the residual inductance caused by the electrode pattern and the like, and the function as a capacitor is lost. For this reason, if the self-resonance frequency is set to be higher than that of the pass band, it is possible to increase the blocking level at a frequency higher than that of the pass band.

  Further, in the above-described embodiment, the first conductor layer 12 on one surface side of the resonance electrodes 191a and 191b is the ground conductor layer. However, similarly to the strip line, the resonance electrodes 191a and 191b are interposed via the dielectric layer. Alternatively, a ground conductor layer may be provided on the other side of the substrate so that an electromagnetic field is confined in the laminated substrate.

  Thus, by providing an open stub in the resonant electrode, it is possible to match the transmission path and generate a dielectric filter with less reflection at a desired frequency. That is, since it is not necessary to provide an external matching circuit, the dielectric filter can be configured at low cost. In addition, since the slot is formed so as to include the region facing the resonance electrode, no other signal wiring pattern or the like is provided between the ground electrode and the resonance electrode. A dielectric filter can be obtained. In addition, since the second dielectric layer 15 is formed using an insulating material having a high dielectric constant in the slot portion, the wiring length of the resonant electrode can be shortened due to the wavelength shortening effect.

  Furthermore, by using the thin film patterning technique, it is possible to reduce the wiring and interval of the resonance electrode, to increase the electromagnetic coupling, to suppress the loss, and to improve accuracy and reduce the thickness. In addition, since the capacitor is built in, parasitic capacitance and the like can be suppressed as compared with the case where an external capacitor component is used, and the number of external components can be reduced, so that downsizing and cost reduction are possible.

  FIG. 7 shows an embodiment of a dielectric filter. Resonance electrode wiring length L is 600 μm, resonance electrode wiring width W is 50 μm, the distance G between the resonance electrodes is 130 μm, and the distance S between the resonance electrode and the end of the slot region is 200 μm. Is 4.6 pF, the capacitance of the capacitor C3 is 3.7 pF, the width p of the stub is 240 μm, and the length d is 40 μm, the pass characteristic of the dielectric filter is shown in FIG. 8, and the reflection characteristic is shown in FIG. become that way. The broken lines in FIGS. 8 and 9 indicate the characteristics when no stub is provided.

  As shown in FIG. 8, a low-loss dielectric filter having a passband of 2.5 GHz and a loss of -1.5 dB can be configured. Further, as shown in FIG. 9, reflection at the center frequency of the pass band can be improved by -10 dB or more.

  As described above, the resonator and the dielectric filter according to the present invention are useful when passing a signal of a desired frequency from a high-frequency signal such as a microwave or a millimeter wave, and a high-frequency such as a mobile phone, a wireless LAN, or a GPS. It is suitable for a portable device using a signal.

It is a figure which shows the structure of a dielectric material filter. It is a section schematic diagram of a dielectric filter. It is a disassembled perspective view of a dielectric filter. It is a figure which shows an equivalent circuit. It is a figure which shows the other structure of a dielectric material filter. It is a partial cross section schematic diagram of a tantalum oxide capacitor portion. It is a figure which shows the Example of a dielectric material filter. It is a figure which shows the passage characteristic of an Example. It is a figure which shows the reflective characteristic of an Example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Dielectric filter, 11 ... Multilayer substrate, 12 ... 1st conductor layer, 13 ... 1st dielectric layer, 14 ... 2nd conductor layer, 15 ... 2nd dielectric Body layer, 16 ... third dielectric layer, 17 ... third conductor layer, 18 ... fourth dielectric layer, 19 ... fourth conductor layer, 20, 21, 22 ... via , 172a, 172b, 173, 192a, 192b ... capacitor electrodes, 174, 175, 194, 195 ... ground electrodes, 191a, 191b ... resonant electrodes, 191a-s, 191b-s ... open stubs , 193a: signal input terminal, 193b: signal output terminal

Claims (11)

A ground conductor layer is formed on one side of a laminated substrate formed by laminating a plurality of dielectric layers and conductor layers, one end being a short-circuited end connected to the ground conductor layer and the other end being an open end A resonance pattern conductor layer having a pair of parallel resonance electrodes is provided to face the ground conductor layer through the dielectric layer, and the open end side of one of the resonance electrodes is used as a signal input terminal, and the other In the resonator using the open end side of the resonance electrode as a signal output terminal,
A resonator having an open stub protruding from the resonance electrode toward the other resonance electrode. A first capacitor having a multilayer structure in which one terminal is connected to the ground conductor layer and the other terminal is connected to the signal input terminal or a resonance electrode using the open end side as the signal input terminal, and one terminal is 2. A second capacitor having a multilayer structure connected to the ground conductor layer and having the other terminal connected to the signal output terminal or a resonance electrode using the open end side as the signal output terminal is provided. 1. The resonator according to 1. The other terminal of the first capacitor is connected to a resonance electrode using the open end side as the signal input terminal,
The other terminal of the second capacitor is connected to a resonance electrode using the open end side as the signal output terminal,
The resonator according to claim 2, wherein the open stub is provided at a connection position of the other terminal of the first and second capacitors. The resonator according to claim 2, wherein the first and second capacitors are capacitors using tantalum oxide as a dielectric. The resonator according to claim 1, wherein a slot is formed in the conductor layer located between the ground conductor layer and the resonance pattern conductor layer so as to include a region facing the resonance electrode. A ground conductor layer is formed on one side of a laminated substrate formed by laminating a plurality of dielectric layers and conductor layers, one end being a short-circuited end connected to the ground conductor layer and the other end being an open end A resonance pattern conductor layer having a pair of parallel resonance electrodes is provided to face the ground conductor layer through the dielectric layer, and the open end side of one of the resonance electrodes is used as a signal input terminal, and the other In the dielectric filter that uses the open end side of the resonance electrode as a signal output terminal, passes a signal in a desired frequency band from the signal input to the signal input terminal, and outputs the signal from the signal output terminal.
A dielectric filter characterized in that an open stub is provided on the resonance electrode so as to protrude toward the other resonance electrode. A first capacitor having a multilayer structure in which one terminal is connected to the ground conductor layer and the other terminal is connected to the signal input terminal or a resonance electrode using the open end side as the signal input terminal, and one terminal is A second capacitor having a multilayer structure connected to the ground conductor layer and connected to the resonance electrode using the other terminal as the signal output terminal or the open end side as the signal output terminal;
The capacitance of the first and second capacitors is adjusted, and a signal in a desired frequency band is passed from the signal input to the signal input terminal and output from the signal output terminal. 6. The dielectric filter according to 6. The other terminal of the first capacitor is connected to a resonance electrode using the open end side as the signal input terminal,
The other terminal of the second capacitor is connected to a resonance electrode using the open end side as the signal output terminal,
8. The dielectric filter according to claim 7, wherein the open stub is provided at a connection position of the other terminal of the first and second capacitors. One terminal is connected to the resonance electrode using the signal input terminal or the open end side as the signal input terminal, and the other terminal is connected to the resonance electrode using the signal output terminal or the open end side as the signal output terminal. A third capacitor having a multilayer structure is provided,
The dielectric filter according to claim 7, wherein a frequency band for blocking a signal input to the signal input terminal is set by adjusting a capacitance of the third capacitor. The dielectric filter according to claim 9, wherein the first to third capacitors are capacitors using tantalum oxide as a dielectric. 7. The dielectric filter according to claim 6, wherein a slot is formed in the conductor layer located between the ground conductor layer and the resonance pattern conductor layer so as to include a region facing the resonance electrode. .

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