JPH06291514A - Irreversible circuit element for microwave - Google Patents

Abstract

PURPOSE:To provide an irreversible circuit element for microwave low in loss and small in size, which can reduce a conductor loss caused by a center electrode. CONSTITUTION:In a sintered body 60 consisting of a microwave magnetic material, plural conductors 55, 56 and 57 separated through a magnetic material layer are laminated, a first center electrode, a second center electrode and a third electrode are constituted of plural conductors 55, plural conductors 56 and plural conductors 57, respectively, and a first-third electrodes are provided in an electrically insulated state, and also, so as to cross in the center part of the sintered body 60.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-reciprocal circuit device used in a microwave band, for example, a non-reciprocal circuit device for microwaves used in a circulator, an isolator or the like.

[0002]

2. Description of the Related Art In recent years, in mobile communication and the like, miniaturization and general-purpose use of high-frequency equipment have been advanced, and miniaturization and cost reduction of non-reciprocal circuit elements used have been strongly demanded.

Examples of the non-reciprocal circuit device as described above include, for example, a plurality of center electrodes arranged in an electrically insulated state so as to intersect with each other, and micro-electrodes above and below the plurality of center electrodes. There is a so-called lumped-constant nonreciprocal circuit element, in which a wave magnetic material is arranged and a direct-current magnetic field is applied by a permanent magnet to the intersecting portion of the plurality of center electrodes. , A lumped constant type circulator, an isolator, and the like.

FIG. 1 is an exploded perspective view for explaining a first example of a conventional nonreciprocal circuit device for microwaves. This microwave non-reciprocal circuit device comprises a rectangular dielectric substrate 1
3 has a laminated structure. Ports 1a to 1f, 2a to 2f and 3 are provided on the upper surfaces of the dielectric substrates 1 to 3, respectively.
a to 3f are formed. Each of the ports 1a to 3f is formed by forming a conductive film so as to be electrically connected to a through-hole electrode arranged so as to surround the center of each of the dielectric substrates 1 to 3.

In the dielectric substrate 1, the port 1a,
The center electrode 4 is formed so as to connect to the port 1d. Similarly, center electrodes 5 and 6 are also formed on the upper surfaces of the dielectric substrates 2 and 3. The center electrodes 4 to 6 are configured to extend in different directions in a state where the dielectric substrates 1 to 3 are stacked, that is, to be crossed in an electrically insulated state via the dielectric substrates. .

The microwave nonreciprocal circuit device is constructed by stacking the dielectric substrates 1 to 3 in the illustrated state. FIG. 2 is an exploded perspective view for explaining a second example of the conventional nonreciprocal circuit device for microwaves.

In the microwave nonreciprocal circuit device of the second example, ports 7a to 7f ... 9a to 9f are formed on the upper surfaces of the dielectric substrates 7 to 9 in the same manner as in the first example, and the center is also formed. Electrodes 10-12 are formed. However, the center electrodes 10 to 12 each have a structure in which two conductors 10a, 10b to 12a, 12b extending in the longitudinal direction are connected at both ends, as shown in the figure. Other structures are similar to those of the microwave nonreciprocal circuit device shown in FIG.

FIG. 3 is an exploded perspective view for explaining a third example of the conventional nonreciprocal circuit device for microwaves. Third
In the microwave nonreciprocal circuit device of the above example, the center electrode 14a made of a metal foil, for example, a Cu foil, is disposed on the disk-shaped microwave magnetic body 13a.

The center electrode 14a is a microwave magnetic material 1
It has a shape that extends in the radial direction through the center of the upper surface of 3a and further reaches the side surface of the microwave magnetic body 13a. Next, an insulating film 15a made of an insulating material is arranged on the center electrode 14a, and another center electrode 14b is arranged thereon so as to intersect with the center electrode 14a. Further, the insulating film 15b, the central electrode 14c, and the insulating film 15c are sequentially arranged on the center electrode 14b, and the microwave magnetic body 13b is formed.
Are stacked and fixed. Then, the microwave magnetic material 13
Permanent magnets are arranged in the upper and lower parts so that a DC magnetic field is applied to the structure sandwiched by a and 13b.

[0010]

In the microwave nonreciprocal circuit device, the wider the center electrode, the smaller the conductor loss. Therefore, the wider center electrode is preferable. However, as the non-reciprocal circuit device is miniaturized, the width of the center electrode is inevitably narrowed. Therefore, in the conventional non-reciprocal circuit device for microwaves described with reference to FIGS. 1 to 3, when further miniaturization is advanced, the center electrodes 4 to 6 and 6.
Since the widths of 10 to 12 and 14a to 14c have to be narrowed, there has been a problem that conductor loss increases and attenuation in the transmission direction increases.

On the other hand, in the method of manufacturing the nonreciprocal circuit device for microwaves described with reference to FIG. 3, the center electrodes 14a to 14c made of metal foil are manually attached to the insulating films 15a to 15c.
It was assembled by alternately stacking with 15c. However, due to the miniaturization of the nonreciprocal circuit device for microwaves, the length of the center electrodes 14a to 14c has become about several mm, and it has become very difficult to assemble them manually. As a result, when a small nonreciprocal circuit device for microwaves is configured, an assembly failure such as a relative displacement between the center electrodes 14a to 14c occurs, and a highly reliable nonreciprocal circuit device for microwaves is provided. It was difficult to get.

Further, since the assembling is done by hand as described above, there is a problem that many assembling failures occur and the manufacturing cost becomes high. Further, as described above, although a relatively large number of parts are required, there is a limit to the cost reduction of individual parts, and it is becoming difficult to reduce the cost of the nonreciprocal circuit device for microwaves.

An object of the present invention is to provide a non-reciprocal circuit device for microwaves which is smaller and has a lower loss without causing a conductor loss in the center electrode due to the size reduction.

[0014]

According to a first aspect of the present invention, a plurality of center electrodes arranged in an electrically insulated state and intersecting each other, and an intersecting portion of the plurality of center electrodes. A magnetic body or a dielectric for microwaves, wherein each center electrode is composed of a plurality of conductors laminated via the magnetic body or the dielectric for microwaves. It is a non-reciprocal circuit device for waves.

With respect to the plurality of conductors forming the center electrode, the plurality of conductors forming the center electrodes may be a magnetic body for microwaves or a dielectric body. May be embedded in the microwave magnetic body or the dielectric body, and the respective center electrodes may be sequentially arranged in the thickness direction in the microwave magnetic body or the dielectric body, or the respective center electrodes may be configured as described in claim 3. Multiple conductors
A conductor embedded in a microwave magnetic material or a dielectric body and forming one center electrode and a plurality of conductors forming another center electrode are formed in a microwave magnetic body or a dielectric body. In, the layers may be randomly laminated in the thickness direction.

[0016]

According to the invention described in claim 1, in the microwave nonreciprocal circuit element, each of the plurality of center electrodes crossed in an electrically insulated state is a microwave magnetic body or a microwave magnetic body. It is composed of a plurality of conductors laminated via a dielectric. Therefore, since each center electrode is composed of the plurality of conductors, it is possible to reduce the conductor loss in the center electrode by increasing the number of conductors. Therefore, even if the non-reciprocal circuit device for microwaves is downsized, it is possible to prevent the reduction of the conductor loss simply by increasing the number of laminated layers. Thus, it is possible to provide a non-reciprocal circuit element for microwaves that is smaller and has low loss.

According to a second aspect of the present invention, the center electrode is embedded in a microwave magnetic body or a dielectric body, and is further laminated in the thickness direction in the microwave magnetic body or the dielectric body. In the microwave nonreciprocal circuit device according to the third aspect of the present invention, the plurality of conductors forming the center electrode are randomly stacked in the thickness direction in the microwave magnetic body or the dielectric body. In any of the inventions of claims 2 and 3,
The plurality of conductors forming the center electrode are embedded in a microwave magnetic body or a dielectric body.
By constructing one center electrode by using a plurality of conductors as in the invention described in (1) above, not only downsizing and loss reduction can be achieved, but also the environmental characteristics of the nonreciprocal circuit device for microwaves can be improved.

Therefore, according to the invention described in claims 1 to 3, it is possible to greatly contribute to miniaturization, generalization and high performance of high frequency equipment such as mobile communication equipment.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be clarified by describing the embodiments of the nonreciprocal circuit device for microwaves of the present invention.

First Embodiment FIG. 4 is an exploded perspective view for explaining a microwave nonreciprocal circuit device according to a first embodiment of the present invention. The microwave nonreciprocal circuit device of the first embodiment is configured by laminating a plurality of rectangular dielectric substrates 21 to 26 and fixing them with an adhesive or the like. As the dielectric substrates 21 to 26,
For example, one made of any dielectric material such as barium titanate-based dielectric ceramics can be used.

On the top surfaces of the dielectric substrates 21 to 26, six ports 21a to 21f ... 26 are arranged around the center of the top surfaces so as to be connected to the through hole electrodes, respectively.
a to 26f are formed. Taking the dielectric substrate 21 as an example, a conductor 27a forming a center electrode is formed on the upper surface of the dielectric substrate 21 so as to connect the ports 21a and 21d among the ports. Similarly, a conductor 27b is formed on the upper surface of the dielectric substrate 22 so as to connect the ports 22a and 22d. The conductors 27a and 27b are coated with a conductive paste and baked, respectively.
Alternatively, it can be formed by an appropriate conductive film forming method.

In the present embodiment, the conductors 27a and 27b are electrically connected to each other at both ends via the through-hole electrodes, thereby forming one center electrode.

Similarly, the conductors 28a and 28b formed on the upper surfaces of the dielectric substrates 23 and 24 are conductors 29 formed on the upper surfaces of the one center electrode and the dielectric substrates 25 and 26, respectively.
Further, a and 29b form one center electrode.

In the microwave nonreciprocal circuit device of this embodiment, each center electrode is composed of a plurality of conductors 27a, 27b to 29a, 29b laminated in the thickness direction as described above. Therefore, even if the width of each of the conductors 27a to 29b becomes narrower with the miniaturization of the nonreciprocal circuit device for microwaves, since one center electrode is composed of a plurality of laminated conductors, the conductor loss is reduced. Can be reduced. Therefore, it is possible to obtain a small nonreciprocal circuit device for microwaves with low loss.

5 to 7 are exploded perspective views showing modified examples of the nonreciprocal circuit device for microwaves of the first embodiment.
These modified examples are the same as the first embodiment except that the center electrode part is changed, and therefore, the same parts are denoted by the same reference numerals and the description thereof is omitted.

In the modification shown in FIG. 5, the conductors 27a to 29 are provided.
b is configured to have a pair of electrode portions formed so as to extend along the longitudinal direction with the slit 30 in between, as illustrated. Therefore, it is possible to further reduce the conductor loss.

Further, in the modification shown in FIG. 6, the conductors 27a and 27b constituting the first center electrode are the dielectric substrate 21,
It is formed on 24. Similarly, conductors 28a and 28b forming the second center electrode are formed on the dielectric substrates 22 and 25. Further, conductors 29a and 29b forming the third center electrode are formed on the dielectric substrates 23 and 26. As described above, the conductors forming the respective center electrodes may be randomly arranged in the thickness direction in the finally laminated state.

In the modification shown in FIG. 7, the conductors 27a to 2a are provided.
9b is formed on one side of a virtual straight line connecting the centers of a pair of ports connected by a conductor. For example, conductor 2
To describe 7a and 27b as a representative, the conductor 27a is formed on one side of the virtual straight line, and the conductor 27b is formed on the other side of the virtual straight line. Therefore, conductor 2
7a and 27b are arranged so as not to overlap each other in the thickness direction in the laminated state. The conductors stacked in the other center electrodes are also arranged so as not to overlap each other in the thickness direction.

Second Embodiment FIG. 8 is an exploded perspective view for explaining a microwave nonreciprocal circuit device according to a second embodiment of the present invention. In the nonreciprocal circuit device for a micro according to this embodiment, the dielectric substrates 31 to 3 are used.
3 are stacked. As the dielectric substrates 31 to 33,
A material made of the same material as in the first embodiment can be used.

On the upper surfaces of the dielectric substrates 31 to 33, six ports 3 are arranged at equal intervals around the center, respectively.
33a to 33f are formed by providing a conductive film so as to be electrically connected to the through hole electrodes. A conductor 34 is formed so as to connect between the ports 31a and 31d, a conductor 35 is formed so as to connect between the ports 32c and 32f, and a conductor 36 is formed so as to connect between the ports 33b and 33e.

On the other hand, for other ports,
Through-hole electrodes 37a to 37 formed at positions close to the center of each port and the upper surfaces of the dielectric substrates 31 to 33.
conductors 40a-40d, 41a-41d, 4 so as to be electrically connected to d, 38a-38d, 39a-39d.
2a to 42d are formed.

The conductors 40a to 42d are laminated on the conductors 34 to 33 with the dielectric substrates 31 to 33 interposed therebetween, respectively.
It is formed so as to partially overlap with any one of 36. Moreover, the through-hole electrodes are electrically connected to the center electrodes that are laminated so as to overlap each other.

For example, the conductors 40b and 40d are formed so as to extend in the same direction as the conductor 35 on the dielectric substrate 32. Similarly, the conductors 35b and 42d also have the conductor 35.
It is formed so as to extend in the same direction as. Moreover, these conductors 40b, 40d, 42b, 42d are
5 is electrically connected. Therefore, in the stacked state, not only the conductor 35 but also the conductors 40b, 40d, 42b, 42d are connected between the pair of ports, so that one conductor is connected as in the first embodiment. The center electrode is composed of a plurality of laminated conductors. Therefore, as in the first embodiment, even if the miniaturization progresses to the extent that the width of each conductor has to be narrowed, the conductor loss can be reduced. An irreversible circuit device for waves can be obtained.

As is apparent from the second embodiment, in the present invention, the plurality of conductors forming the center electrode extend in the same direction as long as they are arranged so as to connect a pair of ports. All conductors do not have to be direct electrical connections between a pair of ports.

[0035] As a third embodiment the third embodiment, a specific experimental example below. Yttrium oxide (Y ₂ O ₃ ) and iron oxide (Fe ₂
A magnetic powder containing O ₃ ) as a main component was dispersed in an organic solvent together with a polyvinyl alcohol-based binder to prepare a magnetic slurry. Using the prepared magnetic slurry,
By the doctor blade method, a magnetic green sheet with a uniform thickness of several tens of μm is formed, and 40 mm × 20 m
Punching to have a rectangular shape.

As described above, the magnetic green sheet 51 having a rectangular planar shape shown in FIG. 9 was prepared. A conductive paste obtained by mixing palladium powder and platinum powder with an organic solvent is printed on the upper surface of the magnetic green sheet 51 by a screen printing method, as shown in FIGS.
The magnetic green sheets 52 to 54 shown in are prepared.

On the magnetic green sheets 52 to 54,
By printing the conductive paste as described above, the elongated rectangular conductors 55 to 57 are formed. The conductors 55 to 57 are formed so as to be offset from each other by about 120 degrees with respect to the centers of the green sheets 52 to 54.

Next, as shown in FIG. 11, a plurality of magnetic material green sheets 52 prepared as described above are laminated, and similarly, a plurality of magnetic material green sheets 53 and 54 are also laminated. A laminate was obtained by laminating and laminating a plurality of plain magnetic green sheets 51 on which conductors were not printed, and pressing them in the thickness direction. This laminated body is shown in FIG.

As is apparent from FIG. 12, in the laminated body 58, a plurality of conductors 55 to 57 are laminated via magnetic layers as shown. This plurality of conductors 55-5
7 will eventually form the center electrode.

Next, the laminated body 58 is replaced with the conductors 55 to 57.
A disk-shaped unfired laminated chip was obtained by punching out a disk-shaped chip having a diameter of about 10 mm, centering on the intersecting portion. FIG. 13 shows an exploded perspective view of the disc-shaped laminated body chip thus obtained. As is clear from FIG. 13, in the disc-shaped laminated body chip, the conductors 55 to 57 are laminated in an electrically insulated state via the magnetic layers. Note that, in FIG. 13, the reference numbers of the magnetic green sheets prepared at the beginning are assigned to the magnetic layers punched into a disc shape.

Next, the disk-shaped laminated body chips prepared as described above are heated at a temperature of 1300 ° C. to 1500 ° C. for 5 minutes.
It was fired by maintaining it for 15 hours to obtain a sintered body. The obtained sintered body is shown in a perspective view in FIG. In the sintered body 60, a plurality of conductors 55 to 57 are laminated inside via a sintered body layer. The outer peripheral side surface 60a of the sintered body 60 obtained as described above is polished to form the conductors 55-5.
Both ends of No. 7 were surely exposed on the side surface to form an external electrode electrically connected to each conductor. The external electrodes were formed by applying a conductive paste containing glass frit and baking it. As described above, the microwave nonreciprocal circuit device of the third embodiment was obtained.

In the microwave nonreciprocal circuit device of this embodiment, the plurality of conductors 55 form one center electrode, the plurality of conductors 56 form one center electrode, and the plurality of conductors 57.
This constitutes one center electrode.

Next, ground electrodes are formed on the upper and lower surfaces of the sintered body 60 of the nonreciprocal circuit device obtained as described above,
Alternatively, the earth electrode made of a metal plate is brought into contact with the above-mentioned 3
One end of each of the two center electrodes was electrically connected to ground.
Further, permanent magnets were brought into contact with the upper and lower parts of the sintered body, and a DC magnetic field was applied to the center electrode by the permanent magnets. further,
A non-reciprocal circuit device was formed by sandwiching the permanent magnet with a metal yoke to form a magnetic closed magnetic circuit. The impedance matching capacitor connected to this type of non-reciprocal circuit device may be provided inside the sintered body or outside the sintered body.

In the microwave nonreciprocal circuit device of this embodiment, since the center electrodes are respectively formed by the plurality of conductors 55 to 57 as described above, the microwave nonreciprocal circuit element is the same as in the first embodiment. Even when the miniaturization of the reversible circuit element progresses, the conductor loss can be reduced. Therefore,
A non-reciprocal circuit element for microwaves with low loss and small size can be obtained. In addition, since the layers can be laminated using the ceramic lamination / integral firing technique as described above, the number of components can be reduced as compared with the conventional method for manufacturing a nonreciprocal circuit element for microwaves using a metal foil. Moreover, complicated manual work can be omitted. Furthermore, since the conductor is formed by the printing process, a thinner conductor can be easily formed. Therefore, a further smaller nonreciprocal circuit device for microwaves can be easily obtained.

Although the magnetic sheet formed by the doctor blade method is used in the third embodiment, a dielectric sheet may be used instead of the magnetic sheet. Further, in the above manufacturing method, the conductor is formed on the green sheet by screen printing, but other printing methods such as gravure printing may be used.

The magnetic or dielectric sheet may be produced not only by the doctor blade method but also by other methods such as extrusion molding. Further, it is not necessary to use a preformed green sheet, for example, by printing a dielectric or magnetic material-containing paste on a support film such as polyester, and drying and then repeating the step of printing a conductive paste, You may form a laminated body.

Further, in the third embodiment, a plurality of conductors forming one center electrode are laminated in the thickness direction,
Next, a plurality of conductors forming another center electrode were laminated in the thickness direction. However, in the third embodiment, different center electrodes are formed as in the case of the modification of the first embodiment. The conductors may be randomly stacked in the thickness direction.

Further, the conductors 55 to 5 constituting the center electrode
The planar shape of No. 7 can be variously modified as in the modification of the first embodiment.

[Brief description of drawings]

FIG. 1 is an exploded perspective view for explaining a first example of a conventional nonreciprocal circuit device for microwaves.

FIG. 2 is an exploded perspective view for explaining a second example of a conventional nonreciprocal circuit device for microwaves.

FIG. 3 is a perspective view for explaining a third example of a conventional nonreciprocal circuit device for microwaves.

FIG. 4 is an exploded perspective view for explaining the first embodiment.

FIG. 5 is an exploded perspective view showing a modification of the nonreciprocal circuit device for microwaves of the first embodiment.

FIG. 6 is an exploded perspective view showing a second modification of the nonreciprocal circuit device for microwaves of the first embodiment.

FIG. 7 is an exploded perspective view showing a third modification of the microwave nonreciprocal circuit device of the second embodiment.

FIG. 8 is an exploded perspective view for explaining a microwave nonreciprocal circuit device according to a second embodiment.

FIG. 9 is a perspective view showing a magnetic green sheet used in a third embodiment.

10A to 10C are perspective views showing a magnetic green sheet printed on a conductor in the third embodiment.

FIG. 11 is an exploded perspective view for explaining a magnetic green sheet to be laminated in the third embodiment.

FIG. 12 is a perspective view showing a laminated body prepared in a third embodiment.

FIG. 13 is an exploded perspective view of a laminated body chip punched into a disc shape.

FIG. 14 is a perspective view for explaining a microwave nonreciprocal circuit device obtained according to a third embodiment.

[Explanation of symbols]

 21-26 ... Dielectric substrate 27a, 27b-29a, 29b ... Conductor 55-57 ... Conductor 60 ... Sintered body (microwave magnetic body)

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Takashi Kawanami 2-26-10 Tenjin Tenjin, Nagaokakyo-shi, Kyoto Murata Manufacturing Co., Ltd. (72) Takashi Hasegawa 2-26-10 Tenjin Tenjin, Nagaokakyo, Kyoto Murata Manufacturing

Claims (3)

[Claims] 1. A plurality of center electrodes which are electrically insulated from each other and which are arranged so as to cross each other, and a microwave magnetic material or a dielectric which is arranged at an intersection of the plurality of center electrodes. The nonreciprocal circuit device for microwaves, wherein each of the center electrodes is composed of a plurality of conductors laminated via a magnetic substance for microwaves or a dielectric substance. 2. A plurality of conductors forming each of the center electrodes are embedded in a microwave magnetic body or a dielectric body, and the center electrodes are sequentially arranged in the microwave magnetic body or the dielectric body in a thickness direction. The nonreciprocal circuit device for microwaves according to claim 1, wherein 3. A plurality of conductors forming each of the center electrodes are embedded in a microwave magnetic body or a dielectric body, and a plurality of conductors forming one center electrode, and another conductor. The nonreciprocal circuit element for microwaves according to claim 1, wherein a plurality of conductors forming the center electrode are randomly laminated in a thickness direction in a magnetic body or a dielectric body for microwaves.