JP3478312B2 - Dielectric resonator and method of manufacturing the same - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dielectric resonator used as a component of various electronic devices and a manufacturing method thereof. In particular, the present invention relates to a dielectric resonator suitable for miniaturization and high performance of electronic equipment and a method for manufacturing the dielectric resonator.

[0002]

2. Description of the Related Art An example of a conventional dielectric resonator is shown in FIG. In FIG. 4, (a) is a perspective view and (b) is a longitudinal sectional view thereof.

In FIG. 4, reference numeral 22 denotes a square pole-shaped dielectric block, and a through hole 24 passing through the center is formed in the dielectric block 22 along its longitudinal direction. An internal conductor (resonant conductor) 26 is provided on the inner surface of the through hole 24. External conductors (ground conductors) 28 are provided on the four outer peripheral surfaces of the dielectric block 22 (the outer surfaces along the longitudinal direction of the dielectric block 22). Further, the end face conductor 30 is provided on one of the two end faces (the outer face that crosses the longitudinal direction) of the dielectric block 22. The end conductor 30 electrically connects the inner conductor 26 and the outer conductor 28.

In this dielectric resonator, since the inner conductor 26 is exposed to the space, it is difficult to obtain a high Q while reducing the size.

For the purpose of solving such a problem, a dielectric resonator as shown in FIG. 5 has been proposed (Japanese Patent Laid-Open No. 5-1).
45308). In FIG. 5, (a) is a perspective view and (b) is a longitudinal sectional view thereof.

In FIG. 5, reference numeral 32 denotes a square pole-shaped dielectric block. The dielectric block 32 has two high dielectric constant layers 34a and 34b and two low dielectric constant layers 35a and 35.
b and a laminated body. And two high dielectric constant layers 34
A film-shaped internal conductor (resonant conductor) 36 extending in the longitudinal direction of the dielectric block 32 is interposed between a and 34b. External conductors (ground conductors) 38 are provided on the four outer peripheral surfaces of the dielectric block 32. An end surface conductor 40 is provided on one end surface of the dielectric block 32. The inner conductor 36 and the outer conductor 38 are formed by the end face conductor 40.
And are electrically connected.

In this dielectric resonator, the inner conductor 36 is barely exposed in the space and the low dielectric constant layers 35a and 35b are formed.
Is used, it is possible to obtain a device having a relatively small size and a relatively high Q.

However, it has been found that there is still room for increasing Q even in the dielectric resonator as shown in FIG. That is, when the high dielectric constant layers 34a and 34b and the low dielectric constant layers 35a and 35b (and also the inner conductor 36) are integrated by co-firing in the manufacture of this dielectric resonator, the dielectric block 32 is formed. Is likely to cause a different phase at the interface between the high dielectric constant layers 34a and 34b and the low dielectric constant layers 35a and 35b.
Therefore, there is a problem that Q cannot be sufficiently increased. Further, in manufacturing the dielectric resonator, the high dielectric constant layers 34a and 34b and the low dielectric constant layer 35a, which are separately fired, are used.
In the case where the dielectric block 32 is formed by bonding with 35b, the number of bonding interfaces is increased and the manufacturing is troublesome, and further, the dielectric constant distribution in the dielectric block 32 changes discontinuously. Therefore, there is a problem that the electric field and the magnetic field are easily disturbed, and therefore Q cannot be sufficiently increased.

In view of the above-mentioned problems of the prior art, it is an object of the present invention to provide a dielectric resonator capable of easily achieving miniaturization while maintaining a higher Q. To do.

Another object of the present invention is to provide a method for easily and suitably manufacturing such a dielectric resonator.

[0011]

According to the present invention, in order to achieve the above object, a pillar-shaped dielectric block and an inner conductor extending in the longitudinal direction inside the dielectric block. And an outer conductor provided on the outer circumferential surface along the longitudinal direction of the dielectric block, wherein the dielectric block gradually extends from the inner conductor side to the outer conductor side. Provided is a dielectric resonator characterized by having a dielectric constant distribution that decreases.

In one aspect of the present invention, the dielectric block has a quadrangular prism shape, and the inner conductor has a film shape parallel to two of the four outer peripheral surfaces of the dielectric block facing each other. ing.

In one aspect of the present invention, an end face conductor is provided on one of the end faces that cross the longitudinal direction of the dielectric block, and the end face conductor electrically connects the inner conductor and the outer conductor. It is connected to the.

In one aspect of the present invention, the dielectric block is made of ceramics.

In one aspect of the present invention, the inner conductor is made of silver, copper or an alloy containing at least one of these.

In one aspect of the present invention, the outer conductor is made of silver, copper or an alloy containing at least one of them.

In one aspect of the present invention, the end surface conductor is made of silver, copper or an alloy containing at least one of these.

According to the present invention, in order to achieve the above object, there is provided a method for manufacturing the dielectric resonator as described above, which comprises (a) a pillar-shaped unsintered dielectric block material. Hold the internal conductor material along the longitudinal direction inside, and promote sintering for the portion closer to the internal conductor material of the dielectric block material by firing these,
Thus, the dielectric block and the inner conductor having a higher dielectric constant toward the inner conductor side are obtained, and the outer conductor is provided on the outer peripheral surface of the dielectric block, the method for manufacturing a dielectric resonator. (B) A column-shaped unsintered dielectric block material holds an inner conductor material along its length, and a substance that increases the dielectric constant of the dielectric block is added to the inner conductor material. By firing these, the substance that increases the dielectric constant is diffused into the dielectric block material, or the internal conductor material itself promotes the sintering of the surrounding dielectric block material, thus A method of manufacturing a dielectric resonator, characterized in that the dielectric block and the inner conductor having a higher dielectric constant toward the conductor side are obtained, and an outer conductor is provided on the outer peripheral surface of the dielectric block. And (c) an inner conductor material along the longitudinal direction thereof is held inside the pillar-shaped unsintered dielectric block material, and an outer conductor material is held on the outer peripheral surface of the dielectric block material, wherein A substance that reduces the dielectric constant of the dielectric block is added to the outer conductor material, and a substance that reduces the dielectric constant is diffused by firing these substances, and thus the inner conductor is formed. A method for manufacturing a dielectric resonator, characterized in that the dielectric block, the inner conductor, and the outer conductor having a dielectric constant distribution that gradually decreases from the side toward the outer conductor are provided. It

In one aspect of the present invention, the substance that increases the dielectric constant is lead, silicon, bismuth, boron, vanadium, lithium, sodium, potassium, silver or copper.

In one aspect of the present invention, the substance that reduces the dielectric constant is alumina, zirconia, carbon or magnesia.

In one aspect of the present invention, the green dielectric block material is formed by laminating two halves each having a rectangular prism shape, and the two halves have good conductivity. And holding the inner conductor material.

In one aspect of the present invention, an outer conductor material having good conductivity and excellent solder resistance is held on the outer peripheral surface of the dielectric block or the dielectric block material, and the dielectric block or the dielectric block material is held. An end face conductor material having good conductivity and excellent solder resistance is held on one end face of a body block material, and an end face conductor is obtained together with the outer conductor.

In one aspect of the present invention, unsintered ceramics is used as the dielectric block material.

In one aspect of the present invention, a silver paste, a copper paste, a mixed paste of silver and copper, or an alloy paste containing at least one of silver and copper is used as the internal conductor material.

In one embodiment of the present invention, a silver paste, a copper paste, a mixed paste of silver and copper, or an alloy paste containing at least one of silver and copper is used as the outer conductor material.

In one aspect of the present invention, a silver paste, a copper paste, a mixed paste of silver and copper, or an alloy paste containing at least one of silver and copper is used as the end surface conductor material.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Specific embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a diagram showing an embodiment of the dielectric resonator of the present invention. In FIG. 1, (a) is a perspective view, and (b) and (c) are a longitudinal sectional view and a lateral sectional view thereof, respectively.

In FIG. 1, reference numeral 2 denotes a square pole-shaped dielectric block. Inside the dielectric block 2, a film-shaped internal conductor (resonant conductor) 4 extending in the longitudinal direction of the dielectric block 2 is provided. Intervenes. External conductors (ground conductors) 6 are provided on the four outer peripheral surfaces of the dielectric block 2 (the outer surfaces along the longitudinal direction of the dielectric block 2). Further, an end surface conductor 8 is provided on one of the two end surfaces (outer surface crossing the longitudinal direction) of the dielectric block 2. The inner conductor 4 and the outer conductor 6 are electrically connected by the end face conductor 8. The film-shaped inner conductor 4 is the dielectric block 2-4.
It is parallel to two opposing outer peripheral surfaces.

The dielectric block 2 is made of ceramics such as bismuth-germanium.

Inner conductor 4, outer conductor 6 and end face conductor 8
Are made of, for example, silver, copper, or an alloy containing at least one of them.

In this embodiment, the dielectric block 2 has a dielectric constant distribution that gradually decreases from the inner conductor 4 side to the outer conductor 6 side. In order to show this, in FIG. 1, the dot density of the portion showing the dielectric block 2 is changed. The higher the dot density, the higher the dielectric constant.
In the case of the dielectric block 2 made of bismuth-germanium-based ceramics, the inner conductor 4 side to the outer conductor 6
It is possible to form a dielectric constant distribution that gradually decreases toward the side, for example, from about 44 to about 36.

According to the dielectric resonator of the present embodiment as described above, the inner conductor 4 is barely exposed to the space, the dielectric block 2 has no discontinuity in permittivity, and the dielectric block is further discontinuous. 2 has a high permittivity on the inner conductor 4 side and a low permittivity on the outer conductor 6 side.
The dimension can be shortened in the longitudinal direction by the contribution of the high dielectric constant portion on the inner conductor 4 side, and the dimension can be shortened by the contribution of the low dielectric constant portion on the outer conductor 6 side in the direction orthogonal to the longitudinal direction. The increase in the (capacitance) component is small, and thus the resonator size can be reduced while keeping Q high.

FIG. 2 is a process chart showing an example of a method for manufacturing the dielectric resonator shown in FIG.

First, as shown in FIG. 2A, an unsintered dielectric material (for example, bismuth-germanium (B
i-Ge-O type) unsintered material of a ceramic dielectric: a square prism-shaped first half part (including an organic binder and a plasticizer) (for example, obtained by sheet molding using a doctor blade) A film-shaped internal conductor material (for example, a silver paste is printed) 14 is formed on one surface of the surface of the film 12) along the longitudinal direction thereof.

Next, as shown in FIG. 2B, a second half portion 13 equivalent to the first half portion 12 made of the unsintered dielectric material is prepared, and the second half portion 13 is prepared as described above. The inner conductor material 14 is overlapped and laminated on the first half portion 12 so as to cover the inner conductor material 14, and the inner conductor material 14 is placed between the two half portions 12 and 13 (that is, inside the unsintered dielectric block material). Hold.

Next, as shown in FIG. 2C, the dielectric block 2 and the internal conductor 4 are formed by degreasing and firing. During this firing, part of the internal conductor material 14 (for example, glass components such as lead, silicon, bismuth, boron, copper contained in the silver paste)
Are diffused into the dielectric block material (12, 13), and the sintering is promoted in a portion closer to the inner conductor material 14 of the dielectric block material, and thus a dielectric material having a higher density and a higher dielectric constant on the inner conductor side. The block 2 and the inner conductor 4 are obtained.

Next, as shown in FIG. 2D, an outer conductor material (for example, a silver paste is printed) 16 is held on the outer peripheral surface of the dielectric block 2, and the above-mentioned FIG. )
By baking at a lower temperature than baking in the process of
A dielectric resonator as shown in FIG. 1 is obtained.

The outer conductor 6 is held on the outer peripheral surface of the dielectric block 2 and the end conductor material (for example, silver paste is printed) on one end surface of the dielectric block 2 to hold the outer conductor 6. At the same time, the end face conductor 8 can be obtained.

In the above manufacturing example, the inner conductor material 1
4) a substance that diffuses into the dielectric block material (12, 13) during firing to increase the dielectric constant of the dielectric block 2 (for example, glass components such as lead, silicon, bismuth, boron, copper). Is added, it is possible to obtain the dielectric block 2 and the inner conductor 4 having a higher dielectric constant toward the inner conductor 4 side.

Further, in the above manufacturing example, FIG.
After the step (1) is completed, the outer conductor material 16 is held on the outer peripheral surface of the dielectric block material (12, 13) and then fired to obtain a dielectric resonator as shown in FIG. You can also At this time, the outer conductor material 16
By adding a substance (for example, alumina [Al2 O3] or magnesia [MgO]) that diffuses into the dielectric block material (12, 13) during firing and reduces the dielectric constant of the dielectric block 2. By setting, the outer conductor 6 has a lower density and the inner conductor 4 has a higher dielectric constant.
It is possible to obtain the dielectric block 2, the inner conductor 4, and the outer conductor 6 having a lower dielectric constant toward the side.

Further, as shown in FIG. 3, thin sheets 12a to 12 are respectively formed as the halves 12 and 13 of the dielectric block material.
It is also possible to use those composed of 12c and 13a to 13c. In this case, as shown in FIG.
The sheet 12a formed with is placed at the center, laminated, and fired. As a result, the state shown in FIG. 2C can be obtained.

[0043]

As described above, according to the present invention, the dielectric block has a permittivity distribution that gradually decreases from the inner conductor side to the outer conductor side, so that the Q of the resonator is kept high. It is possible to downsize and downsize.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of a dielectric resonator of the present invention.

FIG. 2 is a process drawing showing an example of a method for manufacturing the dielectric resonator shown in FIG.

FIG. 3 is a diagram showing a step of the method of manufacturing the dielectric resonator shown in FIG. 1.

FIG. 4 is a diagram showing an example of a conventional dielectric resonator.

FIG. 5 is a diagram showing an example of a conventional dielectric resonator.

[Explanation of symbols]

2 Dielectric block 4 Inner conductor (resonant conductor) 6 External conductor (ground conductor) 8 End conductor 12 Dielectric block material half 13 Half of dielectric block material 14 Inner conductor material 16 outer conductor material

Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01P 7/04 H01P 11/00

Claims (3)

(57) [Claims] 1. A pillar-shaped dielectric block, and an internal conductor extending inside the dielectric block in a longitudinal direction thereof.
A dielectric resonator comprising an outer conductor provided on an outer peripheral surface along a longitudinal direction of the dielectric block, wherein the dielectric block is provided in all directions from the inner conductor side to the outer conductor side. A dielectric resonator having a gradually decreasing dielectric constant distribution. 2. A method of manufacturing a dielectric resonator according to claim 1, maintains an internal conductor material along its longitudinal direction in the interior of the green dielectric block material pillar shape, this
Adding a substance that increases the dielectric constant of the dielectric block to Kode該 inner conductor material advance, the dielectric block substances which increase the dielectric constant by burning them
A dielectric block characterized in that the dielectric block and the internal conductor having a higher permittivity toward the inner conductor side are obtained, and an outer conductor is provided on the outer peripheral surface of the dielectric block. Manufacturing method of body resonator. 3. A method of manufacturing the dielectric resonator according to claim 1.
A method of holding an inner conductor material along a longitudinal direction inside a pillar-shaped unsintered dielectric block material, and holding an outer conductor material on an outer peripheral surface of the dielectric block material, Then, a substance that reduces the dielectric constant of the dielectric block is added to the outer conductor material, and the substance that reduces the dielectric constant is diffused into the dielectric block material by firing them, thus A method of manufacturing a dielectric resonator, characterized in that the dielectric block, the inner conductor, and the outer conductor having a dielectric constant distribution that gradually decreases in all directions from the conductor side to the outer conductor side are obtained. .