WO2023079903A1 - Dielectric filter - Google Patents

Abstract

This dielectric filter (100) comprises a main body (110) having a cuboid shape, and shields (121-126) disposed on side surfaces of the main body (110). The main body (110) includes a plurality of resonator units (131-135) that are arranged in a first direction and crimped. Each of the plurality of resonator units (131-135) includes a dielectric (170) having a cuboid shape, and resonators (141-145) extending in a second direction orthogonal to the first direction in the dielectric (170). The resonators (141-145) are formed by a plurality of plate-shaped conductors (1401, 1402) extending in the second direction. The main surfaces of adjacent conductors (1401, 1402) in the plurality of conductors face each other in the first direction.

Description

dielectric filter

The present disclosure relates to dielectric filters, and more particularly to a structure that suppresses deformation of dielectric filters during the manufacturing process.

Japanese Unexamined Patent Application Publication No. 2002-111310 (Patent Document 1) discloses a laminated dielectric comprising a laminated body in which a dielectric and a conductor are laminated, and an input/output terminal and a ground terminal formed on the outer surface of the laminated body. A body filter is disclosed. A dielectric filter disclosed in Japanese Patent Application Laid-Open No. 2002-111310 (Patent Document 1) includes a plurality of ground electrodes arranged via a dielectric layer, a plurality of resonance elements arranged between the ground electrodes, It includes a coupling electrode that couples adjacent resonant elements, and a coupling suppression electrode that suppresses capacitive coupling between the coupling electrode and the ground electrode. In the dielectric filter disclosed in Japanese Patent Application Laid-Open No. 2002-111310 (Patent Document 1), the coupling suppressing electrode reduces the stray capacitance between the coupling electrode and the ground electrode, thereby preventing deterioration of the frequency characteristics. .

In Japanese Patent Laying-Open No. 2004-48714 (Patent Document 2), a reinforcing electrode mechanically connected to a ceramic layer is arranged inside a laminate in which a plurality of ceramic layers and a plurality of internal electrodes are laminated. A ceramic laminate device is disclosed. Japanese Patent Laying-Open No. 2004-48714 (Patent Document 2) describes that ceramic materials having different dielectric constants may be used for each of the ceramic layers.

Japanese Patent Application Laid-Open No. 2002-111310 JP 2004-48714 A

The resonant element of the dielectric filter disclosed in Japanese Unexamined Patent Application Publication No. 2002-111310 (Patent Document 1) is a so-called distributed constant type resonator, and the capacitance between a plurality of laminated conductors and the inductance of each electrode. achieves a desired resonance frequency.

In the dielectric filter disclosed in Japanese Patent Application Laid-Open No. 2002-111310 (Patent Document 1), a plurality of resonant elements are arranged side by side in a direction orthogonal to the stacking direction of the laminate, and the conductors that constitute each resonant element are It has the structure laminated|stacked in the lamination direction of a laminated body. In such a configuration, the width of the conductors forming each resonant element is restricted due to the overall size of the dielectric filter. Therefore, in order to achieve a desired Q value in each resonant element, it is necessary to increase the number of laminated layers of conductors.

Here, in a device having a laminated structure in which a dielectric and a conductor are laminated, the shape of the device after manufacturing is deformed due to the difference in deformation amount between the dielectric and the conductor during crimping and firing in the manufacturing process. sometimes. As the number of laminated layers of conductors increases, the difference between the deformation amount of the conductor portion and the deformation amount of the dielectric portion increases, and the degree of deformation of the device increases, resulting in dimensional defects and mounting defects. There is a risk of

The present disclosure has been made to solve the above problems, and its purpose is to suppress deformation of the dielectric filter during the manufacturing process.

A dielectric filter according to the present disclosure includes a body having a rectangular parallelepiped shape and a shield arranged on the side surface of the body. The body includes a plurality of resonator units arranged in a first direction and crimped. Each of the plurality of resonator units includes a first dielectric having a rectangular parallelepiped shape and a resonator extending in a second direction orthogonal to the first direction within the first dielectric. The resonator is composed of a plurality of plate-shaped conductors extending in the second direction. Principal surfaces of adjacent conductors in the plurality of conductors face each other in the first direction.

In the dielectric filter according to the present disclosure, flat plate-shaped conductors forming each resonator are arranged with a gap in the arrangement direction of the resonators. With such a configuration, the width direction of each conductor can be made perpendicular to the direction in which the resonators are arranged, and the area of each conductor can be increased. As a result, a desired Q value can be achieved with a smaller number of conductors than in the case where the width of the conductors is in the direction in which the resonators are arranged. Therefore, deformation of the dielectric filter during the manufacturing process can be suppressed.

1 is a block diagram of a communication device having a high-frequency front-end circuit to which the filter device according to Embodiment 1 is applied; FIG. 1 is an external perspective view of a filter device according to Embodiment 1. FIG. 2 is a see-through perspective view showing the internal structure of the filter device of Embodiment 1. FIG. FIG. 4 is a planar transparent view when the filter device of FIG. 3 is viewed from the Z-axis direction; FIG. 4 is a transparent side view of the filter device of FIG. 3 when viewed from the Y-axis direction; FIG. 4 is a diagram for explaining details of electrodes of a resonator; FIG. 4 is a diagram for explaining the electrode arrangement of the resonator of the first embodiment and the resonator of the comparative example; FIG. 11 is a side see-through view of the filter device of Modification 1; FIG. 11 is a side see-through view of a filter device of modification 2; FIG. 11 is a side see-through view of a filter device of modification 3; FIG. 11 is a side see-through view of a filter device of modification 4; 14 is a see-through perspective view showing an internal structure of a filter device of Modification 5. FIG. FIG. 8 is a see-through perspective view showing the internal structure of the filter device of Embodiment 2; FIG. 14 is a side see-through view of the filter device of FIG. 13 as seen from the Y-axis direction; FIG. 10 is a diagram showing a manufacturing process of the shield conductor in the filter device of Embodiment 3; FIG. 11 is a side see-through view of a filter device of modification 6; FIG. 12 is a see-through perspective view showing the internal structure of the filter device of Embodiment 4; FIG. 11 is a side see-through view of the filter device of Embodiment 4; FIG. 11 is a side see-through view of a filter device of modification 7;

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. The same or corresponding parts in the drawings are denoted by the same reference numerals, and the description thereof will not be repeated.

[Embodiment 1]
(Basic configuration of communication device)
FIG. 1 is a block diagram of communication device 10 having high-frequency front-end circuit 20 to which filter device 100 of Embodiment 1 is applied. The communication device 10 is, for example, a mobile terminal typified by a smart phone, or a mobile phone base station.

Referring to FIG. 1 , communication device 10 includes antenna 12 , high frequency front end circuit 20 , mixer 30 , local oscillator 32 , D/A converter (DAC) 40 and RF circuit 50 . High frequency front end circuit 20 also includes bandpass filters 22 and 28 , amplifier 24 and attenuator 26 . In FIG. 1, the high-frequency front-end circuit 20 is a transmission circuit that transmits high-frequency signals from the antenna 12, but the high-frequency front-end circuit 20 is a reception circuit that receives high-frequency signals via the antenna 12. There may be.

The communication device 10 up-converts the transmission signal transmitted from the RF circuit 50 into a high-frequency signal and radiates it from the antenna 12 . The modulated digital signal output from the RF circuit 50 is converted from a digital signal to an analog signal by the D/A converter 40 . The mixer 30 mixes the transmission signal, which has been converted from a digital signal to an analog signal by the D/A converter 40, with an oscillation signal from the local oscillator 32 and up-converts it into a high-frequency signal. A band-pass filter 28 removes unnecessary waves generated by the up-conversion and extracts only signals in a desired frequency band. Attenuator 26 adjusts the strength of the transmitted signal. Amplifier 24 power-amplifies the transmission signal that has passed through attenuator 26 to a predetermined level. The band-pass filter 22 removes unwanted waves generated in the amplification process and allows only signal components in the frequency band specified by the communication standard to pass. A transmission signal that has passed through the bandpass filter 22 is radiated from the antenna 12 .

A filter device corresponding to the present disclosure can be employed as the bandpass filters 22 and 28 in the communication device 10 as described above.

(Configuration of filter device)
Next, a detailed configuration of the filter device 100 according to the first embodiment will be described with reference to FIGS. 2 to 6. FIG. Filter device 100 is a dielectric filter composed of a plurality of resonators that are distributed constant elements.

FIG. 2 is an external perspective view of the filter device 100. FIG. In FIG. 2, only the configuration that can be seen from the outer surface of the filter device 100 is shown, and the internal configuration is omitted. FIG. 3 is a see-through perspective view showing the internal structure of the filter device 100. FIG. Moreover, FIG. 4 is a planar transparent view when the filter device 100 is viewed from the Z-axis direction. FIG. 5 is a side see-through view of the filter device 100 viewed from the Y-axis direction. FIG. 6 is a diagram for explaining the details of the electrodes of the resonator.

2 to 6, the filter device 100 includes a rectangular parallelepiped or substantially rectangular parallelepiped main body 110 in which a plurality of dielectric layers are laminated in the lamination direction. Body 110 has top surface 111 , bottom surface 112 , side surface 113 , side surface 114 , side surface 115 and side surface 116 . A direction orthogonal to the upper surface 111 and the lower surface 112 is defined as the Z-axis direction. The direction orthogonal to the side surfaces 115 and 116 is the X axis, and the direction orthogonal to the side surfaces 113 and 114 is the Y axis. The upper surface 111 is the surface in the positive direction of the Z-axis, and the lower surface 112 is the surface in the negative direction of the Z-axis. The side surface 113 is the side surface in the positive direction of the X-axis, and the side surface 114 is the side surface in the negative direction of the X-axis. Side 115 is the side in the positive direction of the Y-axis and side 116 is the side in the negative direction of the Y-axis.

A flat plate-shaped shield conductor made of a conductive material is arranged on the outer surface of the main body 110 so as to cover each surface. Specifically, a shield conductor 121 is arranged on the upper surface 111 and a shield conductor 122 is arranged on the lower surface 112 . Shield conductors 123 to 126 are arranged on the side surfaces 113 to 116, respectively. The shield conductor can be connected to a ground electrode on a mounting board (not shown) by a connection conductor such as a solder bump. That is, the shield conductor functions as a ground terminal. The shield conductor is formed by coating, transferring, or sputtering a conductive paste on the surface of the main body 110 . A part of the shield conductor may be arranged inside the main body 110 .

The shield conductor 122 on the lower surface 112 side has cutouts in portions facing the side surfaces 115 and 116 . Notches are also formed in portions of shield conductors 125 and 126 on side surfaces 115 and 116 facing lower surface 112 . The input terminal T1 is arranged in the cutout portion on the side surface 116 side, and the output terminal T2 is arranged in the cutout portion on the side surface 115 side.

The input terminal T1 and the output terminal T2 have a substantially L-shaped cross section when viewed from the Y-axis direction. Input terminal T1 is arranged on side surface 115 and bottom surface 112 . The output terminal T2 is arranged on the side surface 116 and the bottom surface 112 . The input terminal T1 and the output terminal T2 are connected to corresponding electrodes arranged on the mounting substrate by connection conductors such as solder bumps.

Next, the internal structure of the filter device 100 will be described. A main body 110 in the filter device 100 is composed of a plurality of resonator units 131 to 135 arranged in the X-axis direction and crimped. More specifically, the resonator units 131, 132, 133, 134, and 135 are arranged in this order from the positive direction to the negative direction of the X axis.

Each of the resonator units 131-135 includes a dielectric 170 having a rectangular parallelepiped shape. Resonator units 131 - 135 respectively include resonators 141 - 145 arranged inside the dielectric 170 . Further, the resonator units 131-135 include capacitive electrodes 151-155 and connection conductors 161-165 and 181-185, respectively. In the following description, the resonator units 131 to 135, the resonators 141 to 145, the capacitor electrodes 151 to 155, and the connection conductors 161 to 165 and 181 to 185 are collectively referred to as the "resonator unit 130", They may be referred to as "resonator 140", "capacitor electrode 150", "connection conductor 160", and "connection conductor 180".

The dielectric 170 has a structure in which a plurality of dielectric layers are laminated in the X-axis direction. Each dielectric layer of the dielectric 170 is made of ceramics such as low temperature co-fired ceramics (LTCC) or resin. Inside the dielectric 170, a plurality of flat plate conductors provided in each dielectric layer and a plurality of vias provided between the dielectric layers constitute the resonator 140, and the distributed constant element Capacitors and inductors are constructed for coupling between. In this specification, the term “via” refers to a conductor that connects electrodes provided on different dielectric layers and extends in the stacking direction. Vias are formed, for example, by conductive paste, plating, and/or metal pins.

In the resonator unit 130 , the resonator 140 extends in the Y-axis direction between the shield conductors 121 and 122 . A positive Y-axis end (first end) of the resonator 140 is connected to the shield conductor 123 . On the other hand, the negative Y-axis end (second end) of the resonator 140 is separated from the shield conductor 124 .

The resonator 140 is composed of a plurality of plate-shaped conductors spaced apart in the stacking direction (X-axis direction). Each of the plurality of conductors has a rectangular shape extending in the Y-axis direction when viewed from the X-axis direction. In each resonator, the main surfaces of adjacent conductors face each other. As shown in FIG. 6, in a cross section parallel to the ZX plane of resonator 140, the plurality of conductors has a substantially elliptical shape as a whole. In other words, the dimension (first width) in the Z-axis direction of the conductor (the conductor 1401 in FIG. 6) arranged at the end in the lamination direction among the plurality of conductors is the same as the conductor arranged in the layer near the center (the conductor in FIG. 6). It is narrower than the Z-axis dimension (second width) of the conductor 1402). It is generally known that high-frequency currents mainly flow near the surface of conductors due to edge effects. Therefore, when the overall cross-sectional shape of the plurality of conductors is a rectangular shape, the current concentrates on the corner portions. As described above, by making the cross-sections of the plurality of conductors substantially elliptical, the current concentration at the corners can be alleviated.

In the resonator 140, the conductor 1401 (first conductor) arranged on the end side is made of a pure metal material such as copper, silver or aluminum. On the other hand, the conductor 1402 (second conductor) arranged near the center is made of a material in which a common material having a coefficient of thermal expansion similar to that of the dielectric 170 is added to metal. That is, the metal content of conductor 1401 is greater than the metal content of conductor 1402 . In order to reduce the loss due to the resonator 140, it is desirable to use pure metallic materials with high electrical conductivity. Structural defects such as cracks due to the difference in thermal expansion coefficient between the metal material and the dielectric 170 are likely to occur during firing of the ceramic in the manufacturing process. Therefore, by using a material added with a common material having a coefficient of thermal expansion similar to that of the dielectric 170, structural defects in the manufacturing process can be suppressed. As for the conductor 1401 arranged on the end portion side, the loss can be reduced by using a pure metal-based material because the current tends to flow due to the edge effect as described above.

As shown in FIG. 4, the plurality of conductors forming the resonator 140 are electrically connected by a connection conductor 160 at a position near the second end. Also, the plurality of conductors forming the resonator 140 are electrically connected by a connection conductor 180 at a position near the first end. Each of the connection conductors 160, 180 is composed of a plurality of vias. A plurality of vias forming connection conductors 160 and 180 are arranged in a zigzag pattern in the X-axis direction.

Assuming that the wavelength of the high-frequency signal transmitted in the resonator is λ, the length of each resonator along the Y-axis, that is, the distance from the first end to the second end is about λ/4. The resonator 140 functions as a distributed constant type TEM mode resonator having a plurality of conductors as central conductors and shield conductors 121 and 122 as outer conductors.

The resonator 141 is connected to the input terminal T1 via vias V10 and V11 and the plate electrode PL1. The resonator 145 is connected to the output terminal T2 through vias V20, V21 and the plate electrode PL2. The thickness d1 of the input terminal T1 and the output terminal T2 is thicker than the thickness d2 of the conductor forming the resonator 140 (d1>d2). At least part of the input terminal T1 and the output terminal T2 is embedded in the dielectric 170 . By configuring the input terminal T1 and the output terminal T2 in such a manner, the electrical conductivity of the input/output portion can be increased to prevent loss and strengthen the terminal strength.

The resonators 141 to 145 are magnetically coupled to each other, and a high frequency signal input to the input terminal T1 is transmitted by the resonators 141 to 145 and output from the output terminal T2. At this time, an attenuation pole is generated depending on the degree of coupling between the resonators, so that the filter device 100 functions as a bandpass filter.

In the filter device 100 , the capacitive electrode 150 is arranged facing the second end of the resonator 140 . A cross section parallel to the ZX plane of the capacitive electrode 150 has a cross section similar to that of the resonator 140 . The capacitive electrode 150 is connected to the shield conductor 124 . As a result, the resonator 140 and the corresponding capacitive electrode 150 form a capacitor. By adjusting the gap (distance in the Y-axis direction) GP between the resonator 140 and the capacitive electrode 150 in FIG. 4, the capacitance value of the capacitor formed by the resonator 140 and the corresponding capacitive electrode 150 is adjusted. be able to.

As a distributed constant type dielectric filter, a plurality of resonators are arranged side by side in a direction orthogonal to the lamination direction of the laminate, as in the above-mentioned Japanese Patent Application Laid-Open No. 2002-111310 (Patent Document 1). A structure in which conductors forming a resonator are laminated in the lamination direction of a laminate is known. In such a configuration, as in the resonator 140X of the comparative example shown in FIG. Therefore, the width of the conductors that make up the resonator can be limited. Therefore, in order to achieve a desired Q value in each resonator, it is necessary to increase the number of laminated layers of conductors.

On the other hand, in the case of a structure in which a dielectric such as a ceramic and a metal conductor are laminated, during the crimping process in the manufacturing process, the dielectric part and the metal part will shrink due to the difference in contraction rate between the dielectric and the metal. The amount of deformation is different. Therefore, as the number of layers of conductors increases, the difference between the amount of deformation in a portion with a high conductor density and the amount of deformation in a portion with a low conductor density in the stacking direction increases, resulting in a defective shape and/or surface texture (unevenness) of the entire filter. aggravation may occur. If so, there is a risk of dimensional defects or poor conduction due to poor mounting.

On the other hand, in the filter device 100 according to the first embodiment, as shown in FIG. 7A, the arrangement direction of the resonators and the stacking direction of the conductors are the same. is relaxed, and the width of each conductor can be set wider than in the case of the comparative example. Therefore, in the resonator of the first embodiment, the number of layers of conductors can be reduced as compared with the resonator of the modified example. As an example, while 17 layers of conductors need to be stacked in the configuration of the comparative example, the same Q value can be achieved with 7 layers of conductors in the configuration of the first embodiment. In another example, while the configuration of the comparative example requires seven layers of conductors, the configuration of Embodiment 1 can achieve an equivalent Q value with four layers of conductors. .

Therefore, by configuring each resonator unit such that the direction in which the resonators are arranged and the direction in which the conductors are laminated are the same as in the filter device 100 of the first embodiment, desired filter characteristics can be obtained with a small number of conductors. can be realized. This reduces the difference in conductor density in the stacking direction within the resonator unit, thereby reducing the difference in the amount of deformation during the manufacturing process, thereby suppressing shape defects and deterioration of the surface properties of the filter device.

The "X-axis direction" and "Y-axis direction" in Embodiment 1 respectively correspond to the "first direction" and "second direction" in the present disclosure. “Top surface 111,” “bottom surface 112,” and “side surfaces 113 to 116” in Embodiment 1 respectively correspond to “first surface” to “sixth surface” in the present disclosure. "Shield conductor 121" to "shield conductor 126" in Embodiment 1 respectively correspond to "first shield conductor" to "sixth shield conductor" in the present disclosure. “Connection conductor 180 (connection conductors 181 to 185)” and “connection conductor 160 (connection conductors 161 to 165)” in Embodiment 1 are respectively referred to as “first connection conductor” and “second connection conductor” in the present disclosure. handle.

(Modification 1)
In Embodiment 1, the case where the cross-sectional shape of each resonator is substantially elliptical has been described. In Modification 1, another example of the cross-sectional shape of the resonator will be described.

FIG. 8 is a side see-through view of the filter device 100A of Modification 1. FIG. In filter device 100A, the cross-sectional shapes of resonators 141A to 145A included in resonator units 131A to 135A are different from filter device 100 of the first embodiment, and other configurations are the same as filter device 100. FIG. In filter device 100A, the description of elements that overlap with filter device 100 will not be repeated.

Referring to FIG. 8, resonators 141A to 145A in filter device 100A are composed of a plurality of conductors having the same shape. Therefore, the cross-sectional shapes of the resonators 141A to 145A are substantially rectangular.

As described above, in order to alleviate current concentration in the corner portions of the resonator due to the edge effect, it is preferable to make the cross-sectional shape of the resonator substantially elliptical as in the first embodiment. However, when the corner portions of the resonators are removed as in the filter device 100, compared to the case where the corner portions are not removed, the facing area, which is the shortest distance between the adjacent resonators, becomes smaller. bond between them weakens.

In the case of the filter device 100A, current concentration may occur at the corners of the resonators, but the degree of coupling between adjacent resonators can be increased.

The cross-sectional shape of the resonator is appropriately selected in consideration of the influence of current concentration on the corners, the degree of coupling between adjacent resonators, size restrictions, and so on.

(Modification 2)
In filter device 100 of Embodiment 1, the case where dielectric 170 forming each resonator unit is made of the same material has been described. In Modified Example 2, a case will be described in which a dielectric having characteristics different from those of other resonator units is used as the dielectric of some of the resonator units.

FIG. 9 is a side see-through view of a filter device 100B of Modification 2. FIG. Filter device 100B has a configuration in which resonator units 132B and 134B replace resonator units 132 and 134 in filter device 100 of the first embodiment. In filter device 100B, the description of elements that overlap with filter device 100 will not be repeated.

Referring to FIG. 9, in filter device 100B, each of resonator units 131, 133, 135 includes dielectric 170 having the same dielectric constant ε1 as filter device 100, and the corresponding resonator is made of the dielectric 170 inside. The resonator unit 132B includes a dielectric 170A having a dielectric constant ε2 (ε2≠ε1) different from that of the dielectric 170, and the resonator 142 is arranged inside the dielectric 170 concerned. Further, the resonator unit 134B includes a dielectric 170B having a dielectric constant ε3 (ε3≠ε1, ε2) different from the dielectrics 170 and 170A, and the resonator 144 is arranged inside the dielectric 170B. .

In this way, the degree of coupling between the resonators is adjusted by using a dielectric having a dielectric constant different from that of the dielectric contained in the other resonator units as the dielectric contained in some of the resonator units. be able to. Therefore, the characteristics of the filter device can be adjusted while the conductors and electrodes are designed in common with the filter device 100 .

In the above description, the case where the dielectric constants are different as the dielectric properties is explained as an example. may be adopted.

In Modified Example 2, each of the " resonator units 131, 133, 135" corresponds to the "first resonator unit" in the present disclosure, and each of the " resonator units 132B, 134B" corresponds to the "second resonator unit" in the present disclosure. Corresponds to the "equipment unit".

(Modification 3)
In Modified Example 3, a configuration in which dielectrics having different characteristics from the dielectrics of the resonator units are arranged between the resonator units will be described.

FIG. 10 is a side see-through view of a filter device 100C of Modification 3. FIG. In filter device 100C, dielectric 170C is arranged between adjacent resonator units. Further, for resonator units 131 and 135 connected to input terminal T1 and output terminal T2, respectively, dielectric 170C is also arranged in portions corresponding to side surfaces 115 and 116 of main body 110. An output terminal T2 is arranged for the input terminal T1.

The dielectric loss tangent δ2 of the dielectric 170C is smaller than the dielectric loss tangent δ1 of the dielectric 170 constituting the resonator unit (δ1>δ2). Thus, the Q value can be improved by making the dissipation factor of the dielectric between the resonator units smaller than that of the dielectric of the resonator units. Note that characteristics other than the dielectric loss tangent (permittivity, temperature characteristics, etc.) may be different.

In Modified Example 3, "dielectric 170" and "dielectric 170C" respectively correspond to "first dielectric" and "second dielectric" in the present disclosure.

(Modification 4)
In Modification 4, a configuration obtained by combining Modification 2 and Modification 3 will be described.

11 is a side see-through view of a filter device 100D of Modification 4. FIG. In the filter device 100D, each of the resonator units 131D to 135D has a first portion in which the resonators are arranged and a second portion other than the first portion. A dielectric 170 is placed in the two parts. A dielectric 170C is arranged in a third portion between the resonators and a fourth portion corresponding to the side surfaces 115 and 116 .

For example, the dielectric 170B placed in the resonator portion may be a dielectric having excellent temperature characteristics with little fluctuation due to temperature changes, and the dielectric 170C placed between the resonator units may have a small dielectric loss tangent and an excellent Q value. By arranging such a dielectric, it is possible to realize a filter device excellent in both temperature characteristics and resonator characteristics.

(Modification 5)
In Modified Example 5, a configuration in which the input terminals and the output terminals have different shapes will be described.

12 is a see-through perspective view showing the internal structure of a filter device 100E of Modification 5. FIG. In filter device 100E, configurations of input terminal T1A and output terminal T2A on side surfaces 115 and 116 are different from filter device 100 of the first embodiment.

More specifically, the input terminal T1A is a plate electrode extending in the X-axis direction near the center of the side surface 115 in the Z-axis direction. Input terminal T1A is connected to resonator 141 by via V10A. Input terminal T 1 A faces the conductor of resonator 141 . Similarly, the output terminal T2A is a plate electrode extending in the X-axis direction near the center of the side surface 116 in the Z-axis direction. Output terminal T2A is connected to resonator 145 by via V20A. Output terminal T2A faces the conductor of resonator 145 .

In FIG. 12, the input terminal T1A and the output terminal T2A are arranged on the side surfaces 115 and 116 from the side surface 113 to the side surface 114 (that is, over almost the entire Y-axis direction). The dimension in the Y-axis direction may be slightly shorter.

Although not clearly shown in FIG. 12, on the side surfaces 115 and 116, the shield conductors 125 and 126 are arranged so as not to overlap the input terminal T1A and the output terminal T2A.

In this way, by increasing the electrode area of the input terminal and the output terminal, it is possible to improve the stability during mounting and improve the plating property when the electrodes are plated. Further, since the input terminal and the output terminal are arranged in parallel to face the resonator, the input terminal and the output terminal function as a shield when viewed from the resonator. This can reduce the influence of the electromagnetic field from the external device on the internal resonator.

[Embodiment 2]
In Embodiment 1, the configuration in which the center positions of the resonators included in the filter device in the Z-axis direction are all arranged at the same position has been described. In a second embodiment, a configuration in which a filter device includes a resonator whose arrangement position in the Z-axis direction is different from that of other resonators will be described.

FIG. 13 is a see-through perspective view showing the internal structure of the filter device 200 of Embodiment 2. FIG. 14 is a side see-through view of the filter device 200 of FIG. 13 as seen from the Y-axis direction. In filter device 200, compared with filter device 100 of the first embodiment, the positions of resonators 141 to 145 in main body 110 in the Z-axis direction are not uniform, and capacitor electrodes PC1, PC2, PC4, and PC5 are added. It has a configured configuration. In filter device 200, the description of elements that overlap with filter device 100 will not be repeated.

Referring to FIGS. 13 and 14, in filter device 200, resonators 141 and 145 are arranged substantially in the center of main body 110 in the Z-axis direction. On the other hand, the resonators 142 and 144 are arranged at positions offset from the resonators 141 and 145 in the negative direction of the Z axis. Further, the resonator 143 is arranged at a position offset from the resonators 141 and 145 in the positive direction of the Z-axis.

By arranging a part of the resonators at offset positions in this way, the degree of coupling between adjacent resonators is slightly reduced compared to the filter device 100 of the first embodiment. On the other hand, since the resonator 141 partially opposes the resonator 143 , a coupling path is generated between the resonators 141 and 143 without passing through the resonator 142 . Similarly, a coupling path occurs between the resonators 142 and 144 without the intervention of the resonator 143, and a coupling path occurs between the resonators 143 and 145 without the intervention of the resonator 144. . That is, so-called jump coupling occurs between the resonators. It is generally known that when interlaced coupling occurs, an attenuation pole occurs in the filter characteristics. Therefore, by offsetting the positions of adjacent resonators in the Z-axis direction and adding an attenuation pole, it is possible to adjust the attenuation characteristic and/or the passband width of the filter device.

Further, as shown in FIG. 13, in the filter device 200, a capacitor electrode PC1 is arranged in a portion of the resonator 141 facing the resonator 142, and a capacitor electrode PC1 is arranged in a portion of the resonator 142 facing the capacitor electrode PC1. A capacitor electrode PC2 is arranged. Similarly, a capacitor electrode PC4 is arranged at a portion of the resonator 144 facing the resonator 145, and a capacitor electrode PC5 is arranged at a portion of the resonator 145 facing the capacitor electrode PC4. All of the capacitor electrodes PC1, PC2, PC4 and PC5 are plate electrodes.

These capacitor electrodes are used to adjust the degree of capacitive coupling between adjacent resonators when the positions of the resonators are offset as described above. That is, these capacitor electrodes are not an essential feature, but are placed as needed depending on the desired filter characteristics. For example, capacitor electrodes may also be added between resonators 142 and 143 and/or between resonators 143 and 144 . Alternatively, the capacitor electrodes PC1, PC2, PC4, and PC5 may be omitted if desired characteristics can be obtained. Also, the dimensions and/or shape of the plate electrodes may be varied.

It should be noted that the capacitor electrodes for adjusting the capacitive coupling between the resonators can also be applied to the filter devices of the first embodiment and each modification.

As described above, in the filter device 200 according to the second embodiment as well, by configuring each resonator unit such that the direction in which the resonators are arranged and the direction in which the conductors are laminated are the same, it is possible to prevent the occurrence of defects in the shape of the filter device. Deterioration of surface properties can be suppressed. Furthermore, by offsetting the Z-axis position of adjacent resonators, attenuation characteristics and/or passband widths can be adjusted.

The "Z-axis direction" in Embodiment 2 corresponds to the "third direction" in the present disclosure.

[Embodiment 3]
In Embodiment 1, the case where the shield conductor is formed on the outer surface by sputtering or the like after forming the main body of the filter device has been described. In the third embodiment, a configuration will be described in which a shield conductor is formed by arranging a dielectric block to which a conductor is attached to a main body composed of a plurality of resonator units.

15A and 15B are diagrams showing the manufacturing process of the shield conductor in the filter device 300 of the third embodiment. Referring to FIG. 15, first, main body 110 is temporarily assembled by arranging a plurality of resonator units 131-135. After that, dielectric block 190 having conductor 195 attached to one main surface of dielectric 170F is placed on upper surface 111, lower surface 112 and side surfaces 113 and 114 of main body 110. As shown in FIG. Then, the filter device 300 is formed by pressing and baking in this state to integrate the resonator units with each other and the resonator unit and the dielectric block. In filter device 300, conductor 195 arranged in dielectric block 190 serves as shield conductors 121-124.

By forming the shield conductor by such a process, the shield conductor can be formed in the same process as the main body, so the manufacturing cost can be reduced.

Further, by using a material having a dielectric constant different from that of the dielectric 170 forming the main body 110 as the material of the dielectric 170F forming the dielectric block, the characteristics of each resonator can be adjusted. .

(Modification 6)
Modification 6 describes a configuration in which a structure for coupling between resonators is incorporated in a dielectric block for forming a shield conductor.

16 is a side see-through view of a filter device 300A of Modification 6. FIG. Referring to FIG. 16, filter device 300A has a structure in which dielectric block 190A is arranged on upper surface 111 of main body 110 and dielectric block 190B is arranged on lower surface 112 thereof. Although not shown in FIG. 16, dielectric blocks 190 similar to those of the third embodiment are arranged on the side surfaces 113 and 114 .

The dielectric block 190A includes a dielectric 170G, a conductor 195, and plate electrodes 310,311. Conductor 195 is disposed on the side of dielectric 170G opposite top surface 111 of body 110 .

The plate electrode 310 is a strip-shaped electrode extending in the X-axis direction and couples the resonators 144 and 145 . The plate electrode 311 is a strip-shaped electrode extending in the X-axis direction and couples the resonators 142 and 143 .

The dielectric block 190B includes a dielectric 170G, a conductor 195, and plate electrodes 312,313. Conductor 195 is disposed on a surface of dielectric 170G opposite bottom surface 112 of body 110 .

The plate electrode 312 is a strip-shaped electrode extending in the X-axis direction and couples the resonators 143 and 145 . The plate electrode 313 is a strip-shaped electrode extending in the X-axis direction and couples the resonators 141 and 142 .

In the filter device 300A, the degree of coupling between the resonators can be increased by the plate electrodes 310-313 arranged in the dielectric blocks 190A and 190B. Further, the plate electrode 312 can form a cross-coupling between the resonators 143 and 145, which produces an attenuation pole in the non-passband. Therefore, by appropriately adjusting the coupling between adjacent resonators and the degree of interlaced coupling, it is possible to improve the attenuation characteristics of the non-passband of the filter device 300A and/or expand the passband width. can be done.

Note that the interlaced coupling is not limited to the mode shown in FIG. 16, and the combination of resonators to be coupled can be appropriately selected according to desired filter characteristics. For example, resonator 141 and resonator 143 may be coupled, or resonator 141 and resonator 144 may be coupled. Alternatively, resonator 142 and resonator 144 may be coupled, or resonator 142 and resonator 145 may be coupled.

[Embodiment 4]
In Embodiment 4, a configuration in which a plurality of flat plate conductors forming each resonator are connected to shield conductors 121 and 122 will be described.

FIG. 17 is a see-through perspective view showing the internal structure of the filter device 400 of Embodiment 4. FIG. FIG. 18 is a transparent side view of the filter device 400 viewed from the positive direction of the X-axis. In filter device 400, resonators 141 to 145 in filter device 100 of Embodiment 1 are replaced with resonators 141B to 145B. In the following description, the description of elements that overlap with filter device 100 will not be repeated. Also, the resonators 141B to 145B may be collectively referred to as "resonator 140B".

17 and 18, a resonator 140B is composed of a plurality of flat plate conductors and connection conductors 160 and 180 connecting the flat plate conductors, like the resonator 140 of the first embodiment. The flat conductor in the resonator 140B includes a main body portion 146 extending in the Y-axis direction and projecting portions 147 and 148 for connecting the main body portion 146 to the shield conductors 121 and 122, respectively.

The projecting portions 147 and 148 extend in the Z-axis direction from the position where the connection conductor 180 is arranged in the body portion 146 and are electrically connected to the shield conductors 121 and 122, respectively. That is, when viewed from the X-axis direction, the resonator 140B has a substantially cross shape. The projections 147 and 148 define the ground end of the resonator 140B. The distance between the second end of each resonator and the protrusions 147 and 148 is designed to be about λ/4, where λ is the wavelength of the high-frequency signal transmitted by the resonator.

A plurality of conductors constituting a resonator are cut into chip sizes by a cutting means such as a dicer or a laser while thin-film conductive sheets or dielectric sheets to which the conductive sheets are attached are superimposed. manufactured by At this time, misalignment in lamination of the conductive sheet and the dielectric sheet, or cutting misalignment in the cutting process may occur.

On the other hand, by providing the protrusions 147 and 148 that define the grounding end of the resonator 140B, it is possible to suppress variations in the resonance frequency of the resonator compared to the case where the protrusions are not provided.

Although it is desirable that the protrusions 147 and 148 are provided on all the flat plate conductors forming the resonator 140B, some of the flat plate conductors may not be provided with the protrusions.

(Modification 7)
Modification 7 is a case where a dielectric block including a structure for coupling between resonators as in Modification 6 is applied to the filter device including resonators having protrusions described in Embodiment 4. will be described.

FIG. 19 is a side see-through view of the filter device 400A of Modification 7 when viewed from the Y-axis direction. Referring to FIG. 19, filter device 400A has a structure in which dielectric block 190C is arranged on upper surface 111 of main body 110 and dielectric block 190D is arranged on lower surface 112 thereof. Although not shown in FIG. 19, dielectric blocks 190 similar to those of Embodiment 3 and Modification 6 are arranged on side surfaces 113 and 114 .

A dielectric block 190C includes a dielectric 170G, a conductor 195, an electrode 196, a via 198, and plate electrodes 310,311. Conductor 195 is disposed on the side of dielectric 170G opposite top surface 111 of body 110 . Dielectric block 190D also includes dielectric 170G, conductor 195, electrode 196, via 198, and plate electrodes 312,313. Conductor 195 is disposed on a surface of dielectric 170G opposite bottom surface 112 of body 110 .

The plate electrodes 310 and 311 in the dielectric block 190C and the plate electrodes 312 and 313 in the dielectric block 190D are strip electrodes extending in the X-axis direction, similar to the filter device 300A of the sixth modification. It is used to connect between vessels. Specifically, plate electrode 310 couples resonators 144 and 145 , and plate electrode 311 couples resonators 142 and 143 . Further, the plate electrode 312 couples the resonators 143 and 145 together, and the plate electrode 313 couples the resonators 141 and 142 together.

Conductors 195 of dielectric blocks 190C and 190D are connected to protrusions 147 and 148 of resonator 140B by vias 198 and electrodes 196. FIG.

Thus, also in the filter device 400A including the resonator 140B connected to the shield conductors 121 and 122 by the projecting portions 147 and 148, the shield conductors 121 and 122 are formed as dielectric blocks, and the dielectric blocks include: By arranging the flat plate electrodes for coupling between the resonators, it is possible to improve the attenuation characteristics of the non-passband of the filter device 400A and/or widen the passband width.

Note that FIG. 19 illustrates a configuration in which a part of the flat plate conductors forming the resonator 140B is provided with a protrusion. A configuration in which a portion is provided may be used.

The embodiments disclosed this time should be considered illustrative in all respects and not restrictive. The scope of the present invention is indicated by the scope of the claims rather than the description of the above-described embodiments, and is intended to include all modifications within the meaning and scope equivalent to the scope of the claims.

10 communication device, 12 antenna, 20 high-frequency front-end circuit, 22, 28 band-pass filter, 24 amplifier, 26 attenuator, 30 mixer, 32 local oscillator, 40 D/A converter, 50 RF circuit, 100, 100A to 100E, 200, 300, 300A, 400, 400A filter device, 110 body, 111 upper surface, 112 lower surface, 113-116 side surface, 121-126 shield conductor, 130-135, 131A-135A, 132B, 134B, 131D-135D resonator unit , 140 to 145, 141A to 145A, 140B to 145B, 140X resonator, 146 main body, 147, 148 protrusions, 150 to 155 capacitive electrodes, 160 to 165, 180 to 185 connection conductors, 170, 170A to 170C, 170F , 170G dielectric, 190, 190A to 190D dielectric block, 195, 1401, 1402 conductor, 196 electrode, 198, V10, V10A, V11, V20, V20A, V21 via, 310 to 313, PL1, PL2 plate electrode, PC1 , PC2, PC4, PC5 Capacitor electrodes, T1A, T1 input terminals, T2, T2A output terminals.

Claims (17)

1. a body having a rectangular parallelepiped shape including a plurality of resonator units arranged in a first direction and crimped;
   a shield disposed on a face of the body;
   each of the plurality of resonator units,
   a first dielectric having a rectangular parallelepiped shape;
   a resonator extending in a second direction perpendicular to the first direction inside the first dielectric;
   The resonator is composed of a plurality of plate-shaped conductors extending in the second direction,
   A dielectric filter, wherein main surfaces of adjacent conductors in the plurality of conductors face each other in the first direction.
2. The shield is
   a first shield conductor and a second shield conductor respectively arranged on a first surface and a second surface perpendicular to the second direction in the main body;
   In the main body, a third shield conductor is arranged on a third surface and a fourth surface connecting the first surface and the second surface along the first direction, and is connected to the first shield conductor and the second shield conductor. 3 shield conductors and a fourth shield conductor,
   2. The dielectric filter of claim 1, wherein a first end of said resonator is connected to said third shield conductor and a second end of said resonator is spaced from said fourth shield conductor.
3. 3. The dielectric filter according to claim 2, wherein each of said plurality of resonator units further includes a capacitive electrode facing said second end and connected to said fourth shield conductor.
4. The resonator is
   a first connection conductor arranged on the first end side and electrically connecting the plurality of conductors to each other;
   4. The dielectric filter according to claim 2, further comprising a second connection conductor arranged on the second end side and electrically connecting the plurality of conductors to each other.
5. The distance in the second direction from the first end to the second end of the resonator is about λ/4, where λ is the wavelength of the high-frequency signal transmitted by the dielectric filter. Item 5. The dielectric filter according to item 4.
6. 5. The dielectric filter according to claim 4, wherein said resonator has a protruding portion arranged on said first end side and connected to said first shield conductor and said second shield conductor.
7. 7. In the resonator, the distance in the second direction from the projection to the second end is approximately λ/4, where λ is the wavelength of the high-frequency signal transmitted by the dielectric filter. A dielectric filter as described in .
8. The dielectric filter according to any one of claims 1 to 7, wherein the shape of the resonator in the cross section perpendicular to the second direction is an ellipse whose minor axis direction is along the first direction.
9. The plurality of conductors includes a first conductor arranged at an end in the first direction and a second conductor other than the first conductor,
   The dielectric filter according to any one of claims 1 to 8, wherein the metal component of said first conductor is greater than the metal component of said second conductor.
10. further comprising a second dielectric disposed between adjacent resonator units;
    10. The dielectric filter according to claim 1, wherein properties of said first dielectric and properties of said second dielectric of said resonator are different.
11. the plurality of resonator units includes a first resonator unit and a second resonator unit;
    11. The dielectric filter according to claim 1, wherein characteristics of said first dielectric in said first resonator unit are different from characteristics of said first dielectric in said second resonator unit. .
12. the plurality of resonator units includes a first resonator unit and a second resonator unit;
    Assuming that a direction orthogonal to both the first direction and the second direction is a third direction,
    What is the position of the center position of the resonator in the first resonator unit in the third direction in the main body and the position of the center position of the resonator in the second resonator unit in the third direction in the main body? A dielectric filter according to any one of claims 1 to 10, which is different.
13. The main body further comprises an input terminal and an output terminal arranged on a fifth surface and a sixth surface orthogonal to the first direction, respectively;
    the shield includes a fifth shield conductor and a sixth shield conductor arranged on the fifth surface and the sixth surface, respectively;
    the input terminal is arranged inside an opening formed in the fifth shield conductor on the fifth surface,
    8. The dielectric filter according to claim 2, wherein said output terminal is arranged inside an opening formed in said sixth shield conductor on said sixth surface.
14. 14. The dielectric filter according to claim 13, wherein said input terminal and said output terminal extend in said second direction.
15. 15. The dielectric filter according to claim 13, wherein the input terminal and the output terminal are thicker than the plurality of conductors forming the resonator.
16. a third dielectric including the first shield conductor and disposed on the first surface;
    14. The dielectric filter of claim 13, further comprising a fourth dielectric including said second shield conductor and disposed on said second surface.
17. at least one of the third dielectric and the fourth dielectric, further comprising a plate electrode for coupling resonators of different resonator units;
    17. The dielectric filter according to claim 16, wherein said plate electrode is arranged between said first shield conductor and said body or between said second shield conductor and said body.

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