JP2003218604A - Laminated dielectric resonator and laminated dielectric filter - Google Patents

Abstract

(57) [Problem] To achieve both miniaturization and low loss of a laminated dielectric filter. A plurality of dielectric layers are laminated, fired and integrated,
In addition, in a laminated dielectric filter 50 having a dielectric substrate 14 having ground electrodes 12a and 12b formed on both main surfaces, and having two sets of resonators in the dielectric substrate 14, The distance between the ground electrodes 12a and 12b formed on both main surfaces of the dielectric substrate 14 is La, and the short-circuited end of the first-layer resonance electrode 16A and the third-layer resonance electrode 20A
When the distance from the short-circuit end at L is Lb, 0.0
3 <Lb / La <0.5 is satisfied.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to several hundred MHz to several G.
Regarding a laminated dielectric resonator and a laminated dielectric filter that form a resonance circuit in the microwave band of Hz,
The present invention relates to a laminated dielectric resonator and a laminated dielectric filter that can realize miniaturization and low loss of the laminated dielectric filter and the like.

[0002]

2. Description of the Related Art Recently, with the diversification of wireless communication systems such as mobile phones, there has been an increasing demand for miniaturization and loss reduction of laminated dielectric filters.

In order to realize the miniaturization of the laminated dielectric filter, it is necessary to make the resonator (resonance electrode) small.

Therefore, conventionally, a method of adding a capacitance to the open end of the resonance electrode is generally used. Particularly, in the laminated dielectric filter 100, as shown in FIGS. Of the dielectric layers (S1 to S9: see FIG. 7) are laminated, fired and integrated, and the dielectric substrate 104 having the ground electrodes 102 formed on at least both main surfaces is provided in the dielectric substrate 14. It is configured to have two sets of resonators (first and second resonators 106A and 106B). Each resonator 106A and 106B has, for example, two resonance electrodes (108A1, 108A2) and (108B), respectively.
1, 108B2) are stacked in the stacking direction, and a dielectric layer is interposed between each resonance electrode in the stacking direction.

Further, each resonance electrode (108A1, 108A)
2) and (108B1, 108B2), three upper and lower inner-layer ground electrodes (112A1, 112A2,
112A3) and (112B1, 112B2, 112B
3) is formed, and the inner layer ground electrodes (11
2A1, 112A2, 112A3) and (112B1,
112B2, 112B3), the resonance electrode (108A
1, 108A2) and (108B1, 108B2) are sandwiched between the open ends.

That is, each resonance electrode (108A1, 108A1
A2) and (108B1, 108B2) open ends and the inner layer ground electrodes (112A1, 112A2, 112A3) and (112B1, 112B2, 112B3) by forming a capacitance, it is possible to lower the frequency of the pass band of the filter. At the same time, the size can be reduced.

[0007]

By the way, in the above-mentioned laminated dielectric filter 100, when the pass band of the filter is further shifted to the low frequency side or the size is reduced,
For example, as shown in FIG. 8, resonators 106A and 106B
Of the resonance electrodes (108A1, 108A2, ...
108An) and (108B1, 108B2, ... 1)
08Bn) is increased and arranged in the stacking direction of the dielectric layers, and each resonance electrode (108A1, 108A2, ... 1)
08An) and (108B1, 108B2, ... 10
8Bn) between the open ends of the inner layer ground electrodes (112
A1, 112A2, ... 112An) and (112B
1, 112B2, ... 112Bn) may be arranged.

However, the resonance electrodes (108A1, 1
08A2, ... 108An) and (108B1, 10
8B2, ... 108Bn) are stacked, the resonance electrodes (108A1, 108B1) and (108An,
There is a problem that the short-circuited end of 108Bn) approaches the ground electrodes 102 on both main surfaces, and as a result, the no-load Q decreases.

Further, the resonance electrodes (108A1, 10A) are simply
8A2, ... 108An) and (108B1, 108
B2, ... 108Bn) are stacked, the coupling adjustment electrode 120 (see FIG. 7) for adjusting the coupling degree between the resonators 106A and 106B, each resonator 106A and 106B, the input terminal and the output. It is necessary to newly provide a space for forming the input electrode 122 and the output electrode 124 that are connected to the terminals, and it is not possible to reduce the size of the multilayer dielectric filter 100.

The present invention has been made in consideration of such problems, and it is possible to realize both miniaturization and low loss of a laminated dielectric filter and a laminated dielectric resonator and a laminated dielectric. Intended to provide a filter.

[0011]

A laminated dielectric resonator according to the present invention comprises a dielectric substrate formed by laminating a plurality of dielectric layers, and ground electrodes formed on both main surfaces of the dielectric substrate. In a laminated dielectric resonator in which a plurality of resonance electrodes are laminated in a substrate with a dielectric layer sandwiched therebetween, a distance between ground electrodes formed on both main surfaces of the dielectric substrate is La, and Among the short-circuit ends of the plurality of resonance electrodes, the short-circuit end closest to the ground electrode formed on one main surface of the dielectric substrate and the closest short-circuit end to the ground electrode formed on the other main surface of the dielectric substrate. When the distance to the short-circuited end is Lb, 0.03 <Lb / La <0.5 is satisfied.

Further, in the laminated dielectric filter according to the present invention, a ground electrode is formed on both main surfaces of a dielectric substrate formed by laminating a plurality of dielectric layers, and a plurality of dielectric electrodes are formed in the dielectric substrate. In a laminated dielectric filter having a resonator,
In the case where the resonator is formed by laminating a plurality of resonance electrodes with dielectric layers sandwiched therebetween, the distance between the ground electrodes formed on both main surfaces of the dielectric substrate is La, and Among the short-circuit ends of the plurality of resonance electrodes, the short-circuit end closest to the ground electrode formed on one main surface of the dielectric substrate and the closest short-circuit end to the ground electrode formed on the other main surface of the dielectric substrate. When the distance to the short-circuited end is Lb, 0.03 <Lb / La <0.5 is satisfied.

First, the relationship between Lb / La and unloaded Q is as follows:
The no-load Q tends to increase until Lb / La is around 0.15, but has a characteristic of decreasing from around 0.15.

Therefore, it is preferable to satisfy the range of 0.03 <Lb / La <0.5, preferably 0.05 <Lb.
/La<0.45, more preferably 0.0
The range of 5 <Lb / La <0.35 is preferable. 0.05 <L
By setting the range of b / La <0.45, it is possible to obtain a low-loss multilayer dielectric resonator and multilayer dielectric filter.

Moreover, since the plurality of resonance electrodes are laminated with the dielectric layers sandwiched therebetween to form one resonator, the pass band of the filter can be further shifted to the low frequency side. In addition to being able to do so, it is also possible to achieve miniaturization.

As described above, in the laminated dielectric resonator and the laminated dielectric filter according to the present invention, both reduction in size and loss of the laminated dielectric filter can be realized.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a laminated dielectric resonator and a laminated dielectric filter according to the present invention will be described below with reference to FIG.
-It demonstrates, referring FIG.

First, in the laminated dielectric resonator 10 according to the present embodiment, as shown in FIG. 1, a plurality of dielectric layers are laminated and fired and integrated, and the ground electrodes 12a are formed on both main surfaces.
And 12b are formed on the dielectric substrate 14.

In the dielectric substrate 14, a plurality (three in the example of FIG. 1) of resonance electrodes 16, 18 and 20 are laminated with a dielectric layer in between.

Particularly, in this embodiment, the dielectric substrate 14
Let La be the distance between the ground electrodes 12a and 12b formed on both main surfaces, and Lb be the distance between the short-circuit end of the first-layer resonance electrode 16 and the third-layer resonance electrode 20. At this time, 0.03 <Lb / La <0.5 is satisfied.

Next, an embodiment (multilayer dielectric filter according to the embodiment) in which the multilayer dielectric filter 50 is constructed by using the multi-layer dielectric resonator 10 according to the above-described embodiment 2 to 5 will be described.

In the laminated dielectric filter 50 according to this embodiment, a plurality of dielectric layers (S1 to S9: see FIG. 3) are laminated and fired and integrated, and the ground electrodes 12 are provided on both main surfaces.
It has a dielectric substrate 14 on which a and 12b are formed, and has two sets of resonators (first and second resonators 10A and 10B) in the dielectric substrate 14. Each resonator 10A and 10B has, for example, three resonance electrodes (16A, 18A, 20A) and (16B, 18B, 2), respectively.
0B) are stacked in the stacking direction, and a dielectric layer is interposed between each resonance electrode in the stacking direction.

When the resonators 10A and 10B are ¼ wavelength resonators, the resonance electrodes (16A, 18A, 20A) and (16B, 18) on the side surface of the dielectric substrate 14 are used.
(B, 20B) the ground electrode 12c (see FIG. 4) is formed on the exposed surface, and each resonance electrode (16A, 18A, 20A)
A structure in which one end of (16B, 18B, 20B) is short-circuited to the ground electrode 12c is adopted.

As shown in FIG. 2, the dielectric substrate 14 has an input terminal 22 formed on one side surface and an output terminal 24 formed on the other side surface. The input terminal 22
Areas (parts where the dielectric substrate 14 is exposed) 26 and 28 for insulation are provided between the ground electrode and the ground electrode, and between the output terminal 24 and the ground electrode.

In this embodiment, the first inner-layer ground electrodes 30A and 30B are formed between the open ends of the first-layer resonance electrodes 16A and 16B and the ground electrode 12a, respectively. Second inner layer ground electrodes 32A and 32B are formed between the open ends of 20A and 20B and the ground electrode 12b, respectively. These first and second inner layer ground electrodes (30A, 30B) and (32A,
32B) is connected to the ground electrode 12d (see FIG. 4) formed on the side surface of the dielectric substrate 14.

In this case, the open ends of the resonators 10A and 10B are connected to the first and second inner layer ground electrodes (30A, 30).
B) and (32A, 32B) through the ground electrode 12a
By capacitively coupling the resonators 10 and 12b, the electrical length of the resonators 10A and 10B can be shortened.

Specifically, the structure of the laminated dielectric filter 50 according to the present embodiment will be described with reference to FIGS. 3 and 4. First, the dielectric substrate 14 includes the first to ninth dielectric layers. It is configured by sequentially stacking S1 to S9. Each of the first to ninth dielectric layers S1 to S9 is composed of one or a plurality of layers.

Two first inner-layer ground electrodes 30A and 30B are formed on one main surface of the third dielectric layer S3, and the coupling degree between the first and second resonators 10A and 10B is increased. A coupling adjustment electrode 34 for adjustment is formed.

Further, on one main surface of the fourth dielectric layer S4,
Two resonance electrodes 16A and 16B of the first layer are formed,
The two resonant electrodes 18A and 18B of the second layer are formed on one main surface of the fifth dielectric layer S5, and the sixth dielectric layer S6 is formed.
On one main surface, the two resonance electrodes 20A and 20 of the third layer are provided.
B is formed.

Further, on one main surface of the seventh dielectric layer S7,
An input electrode 36 for connecting the first resonator 10A and the input terminal 22 (see FIG. 2) via a capacitance, a second resonator 10B and the output terminal 24 (see FIG. 2) with a capacitance And an output electrode 38 for connection via
Two second inner layer ground electrodes 32A and 32B are formed.

Then, as shown in FIG. 4, the dielectric substrate 1
The distance between the ground electrodes 12a and 12b formed on both main surfaces of No. 4 is La, and the resonance electrodes 16A and 16B of the first layer are set.
Short-circuited end in and the third-layer resonance electrodes 20A and 20B
When the distance from the short-circuited end at Lb is Lb, 0.0
3 <Lb / La <0.5 is satisfied.

Here, there is a relationship as shown in FIG. 5 between the above Lb / La and the no-load Q. That is, no load Q
It can be seen that Lb / La tends to increase up to around 0.15, but decreases from around 0.15. As the no-load Q, 0.03 <Lb / La <0.
A range of 5 is good. Preferably, 0.05 <Lb / La <
The range is preferably 0.45, more preferably 0.05 <Lb
The range of /La<0.35 is preferable. 0.05 <Lb / La
By setting it within the range of <0.45, the laminated dielectric resonator 10 and the laminated dielectric filter 50 with low loss can be obtained.

Moreover, the plurality of resonance electrodes 16A, 18A and 20A are laminated with the dielectric layers sandwiched therebetween to form one laminated dielectric resonator 10A, and the plurality of resonance electrodes 16B, 18B and 20B are formed. Since the laminated dielectric resonator 10B is configured by laminating the dielectric layers in between, it is possible to further shift the pass band of the laminated dielectric filter 50 to the low frequency side and to reduce the size. It can also be realized.

As described above, in the laminated dielectric resonator 10 and the laminated dielectric filter 50 according to the present embodiment, it is possible to realize both miniaturization and loss reduction of the laminated dielectric filter and the like. .

In the embodiment described above, two resonators 10 are provided.
Although the example applied to the laminated dielectric filter 50 having A and 10B is shown, the invention can also be applied to a laminated dielectric filter having three or more resonators.

Further, in the above embodiment, each resonator 1
0A and 10B are three-layer resonance electrodes (16A, 1A)
8A, 20A) and (16B, 18B, 20B) are shown as examples, but it is also possible to use one layer of resonance electrodes, two layers of resonance electrodes, or four or more layers of resonance electrodes. May be.

The laminated dielectric resonator and the laminated dielectric filter according to the present invention are not limited to the above-mentioned embodiments, and various structures can be adopted without departing from the gist of the present invention. Of course.

[0038]

As described above, according to the laminated dielectric resonator and the laminated dielectric filter of the present invention, both miniaturization and loss reduction of the laminated dielectric filter can be realized. .

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing the configuration of a laminated dielectric resonator according to an embodiment.

FIG. 2 is a perspective view showing a configuration of a laminated dielectric filter according to the present embodiment.

FIG. 3 is an exploded perspective view showing the configuration of the laminated dielectric filter according to the present embodiment.

FIG. 4 is a vertical cross-sectional view showing the structure of the laminated dielectric filter according to the present embodiment.

FIG. 5 is a characteristic diagram showing a relationship between Lb / La and no-load Q.

FIG. 6 is a vertical cross-sectional view showing the structure of a laminated dielectric filter according to a conventional example.

FIG. 7 is an exploded perspective view showing a configuration of a laminated dielectric filter according to a conventional example.

FIG. 8 is an explanatory diagram showing a structure of a laminated dielectric filter when a large number of resonant electrodes are laminated.

[Explanation of symbols]

10 ... Multilayer Dielectric Resonator 10A, 10B
... Resonators 12a to 12d ... Ground electrode 14 ... Dielectric substrates 16A, 16B ... First-layer resonance electrodes 18A, 18B
... Resonant electrodes 20A and 20B of the second layer ... Resonant electrode 50 of the third layer ... Multilayer dielectric filter

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Yasuhiko Mizutani             2-56, Sudacho, Mizuho-ku, Nagoya-shi, Aichi             Inside Hon insulator Co., Ltd. (72) Inventor Tainobu Saka             2-56, Sudacho, Mizuho-ku, Nagoya-shi, Aichi             Inside Hon insulator Co., Ltd. (72) Inventor Takami Hirai             2-56, Sudacho, Mizuho-ku, Nagoya-shi, Aichi             Inside Hon insulator Co., Ltd. (72) Inventor Kazuhiro Kadota             2-56, Sudacho, Mizuho-ku, Nagoya-shi, Aichi             Inside Hon insulator Co., Ltd. (72) Inventor Kazuyuki Mizuno             2-56, Sudacho, Mizuho-ku, Nagoya-shi, Aichi             Inside Hon insulator Co., Ltd. F-term (reference) 5J006 HB05 JA01 LA02 LA23 NA04                       NC03

Claims (2)

[Claims] 1. A ground electrode is formed on both main surfaces of a dielectric substrate formed by laminating a plurality of dielectric layers, and a plurality of resonance electrodes are sandwiched between the dielectric electrodes in the dielectric substrate. In the laminated dielectric resonator, the distance between the ground electrodes formed on both main surfaces of the dielectric substrate is La, and one of the dielectric substrates is one of the short-circuited ends of the plurality of resonant electrodes. When the distance between the short-circuited end closest to the ground electrode formed on the main surface and the short-circuited end closest to the ground electrode formed on the other main surface of the dielectric substrate is Lb, 0.03 A laminated dielectric resonator satisfying <Lb / La <0.5. 2. A laminated dielectric filter having ground electrodes formed on both main surfaces of a dielectric substrate formed by laminating a plurality of dielectric layers and having a plurality of resonators in the dielectric substrate. When the resonator is formed by laminating a plurality of resonance electrodes with dielectric layers sandwiched therebetween, the distance between the ground electrodes formed on both main surfaces of the dielectric substrate is La, and Among the short-circuit ends of the plurality of resonance electrodes, the short-circuit end closest to the ground electrode formed on one main surface of the dielectric substrate and the closest short-circuit end to the ground electrode formed on the other main surface of the dielectric substrate. A multilayer dielectric filter, wherein 0.03 <Lb / La <0.5 is satisfied, where Lb is the distance from the short-circuited end.