JPH05243824A - Dielectric resonator chip - Google Patents

Abstract

PURPOSE:To provide a dielectric resonator chip of a plate type, which is a low profile type, and also, small in its mounting occupied area, and moreover, excellent in its mechanical strength, and furthermore, can be manufactured easily. CONSTITUTION:A first and a second dielectric layers 1a, 1b are arranged so as to insert and hold a band-like inner conductor 2, and also, this resonator chip consists of a laminated body in which outer conductors 3a, 3b are formed so as to insert and hold a first and a second dielectric layers. In one end part of the laminated body, a terminal electrode 4b is formed so that the outer conductors 3a, 3b and the inner conductor are connected to each other, and on the other end part, a terminal electrode 4a connected to the inner conductor 2 directly or through a capacitive component is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat plate type dielectric resonator chip.

[0002]

2. Description of the Related Art Dielectric resonators are widely used in oscillating circuits of communication equipment and the like, and at the present time, with the miniaturization of communication equipment, a low height type and a small mounting area are strongly demanded.

As a low-profile resonator, conventionally, as shown in FIG. 8, a strip-shaped inner conductor 82 is formed inside a dielectric substrate 81 composed of two dielectric layers 81a and 81b. Further, the outer conductors 83a and 83b are formed on the outer surface of the substrate 81.
A dielectric resonator 80 having a structure is known (Japanese Unexamined Patent Publication No. Sho 6 (1999) -63138).
2-120101).

More specifically, the outer conductors 83a and 83b are formed on the substrate 81 excluding one end face (open end face) of the dielectric substrate 81 from which the inner conductor 82 extends and a portion near the open end face of the lower dielectric layer. The strip-shaped inner conductor 82 and the outer conductors 83a and 83b are connected to each other via the other end surface (short-circuited end surface) of the dielectric substrate 81 formed on the entire surface and extending from the inner conductor 82.

When used as a resonator, the outer conductor 83
Inner conductor 82 that grounds a and 83b and extends to the open end face side
It is used as a resonator by applying a signal to the outer conductors 83a and 83b.

This type of resonator is used as a resonance circuit portion in an oscillation circuit, or is used as a resonance circuit portion by providing a capacitance component in an inner conductor of the resonator, and a plurality of resonators are capacitively coupled. , Used as a filter.

[0007]

However, in the above-mentioned resonator, when connecting to a printed wiring board, a terminal electrode is formed on the same plane as the outer conductor, and a separate connecting lead such as wire bonding is formed on the inner conductor. Since it has to be mounted on a printed wiring board by using a body, the mounting efficiency is extremely low.

The present invention has been made in view of the above problems, and provides a flat dielectric resonator chip which is low in height, has a small mounting area, and is easy to manufacture. is there.

[0009]

In order to achieve the above-mentioned object of the present invention, the present invention arranges the first and second dielectric layers so as to sandwich the strip-shaped inner conductor. A dielectric resonator chip comprising a laminated body in which an outer conductor is formed so as to sandwich the first and second dielectric layers, wherein the outer conductor and the inner conductor are provided at one end of the laminated body. A terminal electrode is formed so as to be connected to and, and a terminal electrode to which the inner conductor is connected directly or via a capacitance component is formed at the other end.

[0010]

As described above, according to the present invention, the inner conductor and the outer conductor forming the resonator are laminated via the dielectric layer, and the terminal electrodes are formed at both ends of the laminated body. When mounting on a wiring board, surface mounting can be easily performed by using this terminal electrode.

Further, one of the terminal electrodes also serves as a conductor for connecting the inner conductor and the outer conductor, and the other of the terminal electrodes is a conductor exposed to the outside either directly with the inner conductor or through a capacitance component. Therefore, a special conductor film for connecting the inner conductor and the outer conductor is not required, and the manufacturing method is extremely easy.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The dielectric resonator chip of the present invention will be described below in detail with reference to the drawings. 1 is an external view of a dielectric resonator chip of the present invention, FIG. 2 shows a sectional structure taken along line AA in FIG. 1, and FIG. 3 shows a sectional structure taken along line BB in FIG. ..

In the figure, a dielectric resonator chip 10 includes a dielectric substrate 1 having at least two dielectric layers 1a and 1b, an inner conductor 2, outer conductors 3a and 3b, and a terminal electrode 4.
It is composed of a and 4b.

The dielectric substrate 1 is made of a dielectric material such as barium titanate and has a rectangular shape. The dielectric substrate 1 is configured by integrating dielectric layers 1a and 1b made of a dielectric material.

The inner conductor 2 is made of silver, copper, an alloy thereof, or the like, and has a strip shape with a predetermined width inside the dielectric substrate 1, that is, between the first dielectric layer 1a and the second dielectric layer 1b. Then, the end part from one end face (open end face) to the other end face (short circuit end face),
It is formed so that each is exposed.

The outer conductors 3a, 3b are made of silver, copper, an alloy thereof, or the like, and except for the open end surface side portion of the dielectric substrate 1,
It is formed on the upper surface side of the dielectric layer 1a and on the lower surface side of the dielectric layer, respectively. Here, the important thing is that the outer conductors 3a, 3b
That is, the short-circuited end face side is formed up to the ridge portion of the short-circuited end face of the dielectric substrate 1.

The terminal electrodes 4a and 4b are formed on both end portions of the dielectric substrate 1, and the structure thereof is Ag from the substrate 1 side,
Alternatively, it is composed of an Ag alloy layer and a plating layer. This plating layer prevents the terminal electrodes 4a and 4b from being eroded by solder when soldered to a printed wiring board, and specifically has a two-layer structure of Ni plating and solder plating.

As in the present invention, the terminal electrodes 4a and 4b are
By forming on the open end surface and the short-circuited end surface of the dielectric substrate 1, for example, the terminal electrode 4a on the open end surface side does not connect to the outer conductors 3a and 3b, but the extended portion on the open end surface side of the inner conductor 2 is formed. Can be directly connected. Moreover, the outer conductors 3a and 3b and the inner conductor 2 are formed by the terminal electrode 4b on the short-circuited end face side.
And can be joined. In particular, the outer conductors 3a and 3b can be connected to the inner conductor 2 with a relatively wide width corresponding to the width of the inner conductor 2, and the outer conductors 3a and 3b can be connected to each other. It is possible to connect over the entire width of the outer conductors 3a, 3b, that is, over the entire width of the substrate 1, and it is possible to connect in a low resistance state.

When mounting on a printed wiring board (not shown), cream solder is applied to two terminal pads formed on the printed wiring board, and the terminal electrodes 4a, 4b are placed so that they come into contact with each other, put into a reflow furnace, and solder jointing can be performed at once like other electronic parts, and there is no need for a metal case etc. that conventionally encases a resonator. Becomes

Next, a method of manufacturing the dielectric resonator chip 10 of the present invention will be described. The manufacturing method is the dielectric layer 1
a step of forming the dielectric sheets 10a, 10b to be the a and 1b, a step of forming a conductor film to be the inner conductor 2 and the outer conductors 3a and 3b on the the sheets 10a and 10b, and laminating the sheets 10a and 10b. It comprises a step of pressure bonding and division, a step of firing, a step of dividing the fired laminated body, and a step of forming a terminal electrode.

First, the dielectric sheets 10a and 10b to be the dielectric layers 1a and 1b are formed.

That is, a paste of a dielectric material having a predetermined dielectric constant is molded into a dielectric tape having a predetermined thickness by a doctor blade method or the like. Next, the tape is cut into a size such that a plurality of dielectric resonator chips 10 ... Can be extracted, and the dielectric sheets 10a to be the dielectric layers 1a and 1b,
Form 10b.

Next, the inner conductor 2 is attached to each of the sheets 10a and 10b.
Then, a conductor film to be the outer conductors 3a and 3b is formed. That is,
Each sheet 10 to be the first dielectric layer 1a shown in FIG.
a is a region in which the dielectric resonator chip 10 is finally formed (the boundary line thereof is indicated by an alternate long and short dash line in the figure),
A conductor film 11 to be the outer conductor 3a is formed on the upper surface of Ag, C
Screen printing is performed by using u and an alloy thereof, for example, a conductive paste containing Ag-Pd as a main component.

Also, the second dielectric layer 1b shown in FIG.
The sheet 10b to be formed has a conductor film 12 to be the band-shaped inner conductor 2 printed on the upper surface in consideration of the region to be the resonator chip 10 ... And the second dielectric shown in FIG. Layer 1
The conductor film 13 that becomes the outer conductor 3b is printed on the back surface of the sheet 10b that becomes b.

The above-mentioned conductor films 11 to 13 are made of Ag or Cu.
The alloy, for example, Ag—Pd, is formed of a conductive paste containing a conductive material and has a film thickness of about 10 μm. After printing this paste, it is dried.

Next, the sheets 10a and 10b are laminated and pressure-bonded. Specifically, the sheets 10a and 10b are aligned and laminated, and a predetermined pressure and temperature are applied to form a laminated body. After obtaining this laminated body, it is cut in consideration of a region (a boundary shown by a dashed line in the figure) to be a dielectric resonator chip. As a result, a laminated body of the dielectric substrate 1 (before firing) of the dielectric resonator chip 10 is obtained.

Next, the laminate is fired. By this firing, the dielectric layers 1a and 1b are integrally sintered, and at the same time, the inner conductor film 12 and the outer conductor films 11 and 13 are sintered to form the inner conductor 2 and the outer conductors 3a and 3b. The firing temperature varies depending on the dielectric material, but the firing temperature is, for example, 900 to 1300 ° C. The conductor paste may be selected in consideration of the firing temperature, and in the case of firing at 1300 ° C,
A silver-palladium paste is used because it exceeds the melting points of silver and copper.

Finally, the terminal electrodes 4a and 4b are formed.
Specifically, the fired laminated body is held by a jig that holds the central portion of the dielectric substrate 1 and the Ag paste is applied to both ends of the laminated body by a transfer method or a dipping method.
Then, bake at about 800 ° C. Then, the Ag layer is coated with Ni plating or solder plating by a plating method.

According to the above manufacturing method, printing, division, firing, and formation of terminal electrodes on the conductor film on the dielectric sheet are performed, so that a large number of dielectric resonator chips can be collectively formed. become.

Next, another embodiment of the present invention will be described with reference to FIG.

The dielectric resonator chip 20 shown in FIG.
To the inner conductor 2 via the capacitance component C. The capacitance component C is added to the terminal electrode 41a on the open end face side.

In the figure, capacitor electrodes 5a and 5b are formed on the open end surface side of the main surface of the dielectric substrate 1 on which the outer conductors 3a and 3b are formed. Moreover, the inner conductor 2 does not extend to the open end surface of the dielectric substrate 1. The terminal electrode 41a on the open end face side is formed so as to be connected to the capacitance electrodes 5a and 5b. Therefore, the terminal electrode 41a is connected to the inner conductor 2 via the capacitance C generated at the opposing portions of the capacitance electrodes 5a and 5b and the inner conductor 2.

Such a dielectric resonator chip is suitable for use in a resonance circuit portion of an oscillation circuit or when a plurality of dielectric resonator chips are connected and used as a filter.

Further, another aspect of the present invention will be described with reference to FIG.

In the illustrated dielectric resonator chip 30, one outer conductor 3b is formed inside the dielectric substrate 1. Specifically, the dielectric substrate 1 has at least three dielectric layers (1a, 1b, 1c). In this way, the outer conductor 3
By providing the dielectric layer 1c outside b, the rigidity of the dielectric substrate 1 itself can be improved. In the manufacturing method, the conductor film 11 which becomes the outer conductor 3a is formed on the upper surface of the sheet 10a which becomes the first dielectric layer 1a, and the second dielectric layer 1
Conductor film 1 which becomes inner conductor 2 on the upper surface of sheet 10b which becomes b
2 is formed, the conductor film 13 that becomes the outer conductor 3b is formed on the upper surface of the sheet 10c that becomes the third dielectric layer 1c, and the sheets 10a to 10c are laminated, cut, sintered, and further the terminal is formed. This is achieved by forming the electrodes 4a, 4b.

Such one outer conductor 3a is exposed because the dielectric resonator chip is post-processed so that a part of the outer conductor 3a is removed in accordance with the resonance frequency so that the frequency can be adjusted. This is because

Further, as shown in FIG. 7, two outer conductors 3a and 3b can be formed inside the dielectric substrate 1. In this case, in the manufacturing process, the dielectric sheet 10x (not shown) on which the conductor film is not formed is formed on the sheet 10a which is the first dielectric layer 1a on which the conductor film 11 which is the outer conductor 3a is formed. Can be easily achieved by stacking. In this case, since no conductor film was formed on both main surfaces of the fired laminated substrate, the terminal electrode 4
When forming a and 4b, especially the terminal electrode 4a on the open end face side
With regard to (3), it is possible to easily form without needing to consider erroneous connection with the outer conductors 3a and 3b.

As shown in FIGS. 6 and 7, the outer conductors 3a, 3
When b is formed inside the dielectric substrate 1, the dielectric layers 1x, 1c on the outer side do not need to take into consideration a predetermined dielectric constant and the like. It can be made quite thick. By doing so, the rigidity of the dielectric substrate 1 after firing can be greatly increased, and warpage during firing can be prevented.

Also, when mounted on a printed wiring board, the outer conductors 3a and 3b are not exposed to the outside, and the handling thereof is extremely easy.

Further, a transparent insulating layer may be formed on the upper surface side of the outer conductor 3a. Specifically, immediately after stacking, overglass containing silica or the like as a main component is applied, cut, and fired to simultaneously form. As a result, the outer conductor 3a can be protected, and at the same time, only a part of the outer conductor 3a can be erased by irradiating the YAG laser through the transparent insulating layer, so that the resonance frequency of the resonator can be adjusted. It will be possible.

After forming the terminal electrodes 4a and 4b, an insulating layer may be provided so as to cover the outer conductors 3a and 3b.

[0042]

As described above, according to the present invention, the inner conductors and the outer conductors are connected to each other through the terminal electrodes, and the terminal electrodes are low-profile type and can be mounted on the printed wiring board by using the terminal electrodes. A small dielectric resonator chip can be achieved.

[Brief description of drawings]

FIG. 1 is an external view of a dielectric resonator chip of the present invention.

FIG. 2 is a cross-sectional view taken along the line AA of FIG.

3 is a cross-sectional view taken along the line BB of FIG.

FIG. 4A to FIG. 4C are schematic views showing one step of the manufacturing process of the present invention.

5 is a cross-sectional view of another dielectric resonator chip of the present invention, which corresponds to FIG.

FIG. 6 is a sectional view of another dielectric resonator chip of the present invention, which corresponds to FIG.

FIG. 7 is a cross-sectional view of another dielectric resonator chip of the present invention, which corresponds to FIG.

FIG. 8 is an external perspective view of a conventional dielectric resonator.

[Explanation of symbols]

 10 ... Dielectric resonator chip 1 ... Dielectric substrate 1a-1c ... Dielectric layer 2 ... Inner conductor 3a, 3b ... Outer conductor 4a 4b ... Terminal electrode

Claims (1)

[Claims] 1. A first and a second dielectric layer are arranged so as to sandwich a strip-shaped inner conductor, and an outer conductor is formed so as to sandwich the first and second dielectric layers. A dielectric resonator chip comprising a laminated body, wherein a terminal electrode is formed at one end of the laminated body so that the outer conductor and the inner conductor are connected, and the inner conductor is directly or at the other end. A dielectric resonator chip, wherein a terminal electrode connected via a capacitance component is formed.