JP3206577B2 - Composite substrate type non-reciprocal circuit device 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 composite substrate type non-reciprocal circuit device and a method of manufacturing the same. The present invention relates to a substrate type non-reciprocal circuit device and a method for manufacturing the same.

[0002]

2. Description of the Related Art As a non-reciprocal circuit device of this type, a composite substrate type circulator disclosed in Japanese Patent Application Laid-Open No. 61-288486 has been known. This circulator has such characteristics that there is almost no attenuation in the signal transmission direction and the attenuation is large in the reverse direction, and it is employed in transmission circuit units of mobile communication devices, mobile phones, and the like.
As shown in FIG. 17 (d), a circulator described in the publication discloses a ferrite disk 3
Is embedded, and the central portion 4a of the circuit pattern 4 is
Circuit pattern 4 so that
Are formed. In this composite substrate type circulator, the dielectric loss of alumina ceramic is smaller than that of ferrite, so that the loss is lower than that of a substrate made of only ferrite material, and a mixer and isolator are integrally formed. It has the advantage that it can be integrated.

In order to produce such a composite substrate type circulator, first, as shown in FIG. 17A, a through hole 2 is formed in a ceramic green sheet 1a.
As shown in FIG. 17B, after inserting a sintered ferrite disk 3 having a diameter slightly smaller than the hole diameter, the green sheet 1a is fired as shown in FIG. / Create a ceramic composite substrate 101. Next, as shown in FIG. 17D, using a print mask (not shown) designed and designed based on the nominal shrinkage of the material composition of the green sheet 1a based on firing conditions such as temperature, A ferrite disk 3 is formed on one surface of the composite substrate 101 by using a gold or silver based conductive paste.
The circuit pattern 4 is printed and printed such that the center of the central circular portion 4a of the circuit pattern 4 formed in accordance with the shape of the above and the center of the ferrite disk 3 coincide. Further, the ground conductor layer 5 is printed on the other surface of the composite substrate 101,
Bake. In this case, in order to reduce the cost of parts, a large number of through holes are provided on one large green sheet at equal intervals, a ferrite disk is inserted into each through hole, and a large number of circulators are used with the same green sheet. I am trying to create it.

[0004]

However, in the conventional method of manufacturing a composite substrate type circulator, after the ferrite / ceramic composite substrate 101 is formed by firing,
The circuit pattern 4 is printed and printed. in this case,
When printing is performed using the above-described print mask, as shown in FIG. 18, the center of the circuit pattern corresponds to the variation in the shrinkage rate due to the variation in the manufacturing conditions between the manufacturing lots and the firing lots of the green sheets. The center of the portion 4a may deviate from the center position of the ferrite disk 3. In particular, the larger the number of circulators to be made in a large ceramic, the greater the deviation, and the circuit pattern protrudes from the ferrite disk. Note that there is a composite substrate type isolator as one of the non-reciprocal circuit elements. However, since the composite substrate type isolator has substantially the same structure as the composite substrate type circulator, there is a similar problem with the composite substrate type isolator.

The present invention has been made in view of the above circumstances, and suppresses the displacement of a ferrite disk and a circuit pattern due to a variation in shrinkage of a substrate when a ferrite / ceramic composite substrate is produced by firing. It is an object of the present invention to provide a composite substrate type non-reciprocal circuit device capable of improving characteristics and reliability and a method of manufacturing the same.

[0006]

[0007]

[0008]

According to a first aspect of the present invention, there is provided a composite substrate in which a ferrite disk is embedded in a first through hole of a ceramic plate; A first ceramic layer laminated on one surface of the composite substrate with a circuit pattern having a portion adjacent to the first substrate, a ground conductor layer formed on the other surface side of the composite substrate, And a second ceramic layer interposed between the composite ceramic substrate and the composite ceramic substrate, wherein the second ceramic layer has a diameter smaller than the diameter of the ferrite disk. A second through-hole having a small diameter and adjacent to the ferrite disk is formed, and a buried conductor layer in contact with the ground conductor layer is buried in the second through-hole. And

According to a second aspect of the present invention, there is provided the composite substrate type non-reciprocal circuit device according to the first aspect, wherein the circuit pattern extends from a portion adjacent to the ferrite disk to an end of the composite substrate. , An input / output terminal is formed at the end thereof, and a hole for the input / output terminal is formed in a portion of the first ceramic layer corresponding to the position of the input / output terminal. The input / output terminal is exposed.

According to a third aspect of the present invention, there is provided the composite substrate type non-reciprocal circuit device according to the first or second aspect, wherein the circuit pattern has an impedance adjustment pattern, and is provided at a position of the impedance adjustment pattern. An impedance adjustment hole is formed in a corresponding portion of the first ceramic layer, and the impedance adjustment pattern is exposed in the impedance adjustment hole.

[0011] The invention according to claim 4 is based on claim 1,
4. The composite substrate type non-reciprocal circuit device according to 2 or 3, wherein the circuit pattern has a connection portion of a termination resistor, and a termination resistor is provided on a portion of the first ceramic layer corresponding to the location of the connection portion. A connection hole is formed, and a connection portion of the terminating resistor is exposed in the hole.

[0012]

[0013]

According to a fifth aspect of the present invention, there is provided a composite substrate in which a ferrite disk is embedded in a first through hole of a ceramic plate, and a first substrate laminated on one surface of the composite substrate.
A circuit pattern formed on the surface of the first ceramic layer opposite to the composite substrate so that at least a part thereof is located above the ferrite disk; and the other surface of the composite substrate A non-reciprocal circuit device of a composite substrate type comprising: a ground conductor layer formed on the substrate; and a second ceramic layer interposed between the ground conductor layer and the composite substrate. The ceramic layer has a diameter smaller than the diameter of the ferrite disk, a second through hole adjacent to the ferrite disk is formed, and the second through hole is in contact with the ground conductor layer. Embedded conductor layer is embedded.

According to a sixth aspect of the present invention, there is provided the composite substrate type non-reciprocal circuit device according to the fifth aspect, wherein the first ceramic layer has a diameter smaller than a diameter of the ferrite disk. A third through hole is formed adjacent to the ferrite disk, and a buried conductor layer that is in contact with the circuit pattern is buried in the third through hole.

The invention according to claim 7 relates to a method of manufacturing a non-reciprocal circuit element of a composite substrate type, wherein a first green sheet having a circuit pattern formed on one surface is placed on the upper side of the circuit pattern. The process of placing it facing down,
A plate-shaped second green sheet having a first through hole is provided.
Stacking on the first green sheet such that at least a part of the circuit pattern and the first through hole are adjacent directly or via the first green sheet; and Pressing the first green sheet and the second green sheet, and the first green sheet laminated on the first green sheet.
Fitting a sintered ferrite disk into the through hole of
A plate-shaped third conductor having a ground conductor layer formed on one surface and having a buried conductor layer in contact with the ground conductor layer embedded in a second through hole having a diameter smaller than that of the ferrite disk.
The second green sheet so that the surface opposite to the surface on which the ground conductor layer is formed faces the second green sheet, and the buried conductor layer is on the ferrite disk. Laminating the first green sheet, the second green sheet, and the third green sheet, and laminating the first green sheet, the second green sheet, and the third green sheet; And firing the third green sheet.

The invention according to claim 8 relates to a method for manufacturing a composite substrate type non-reciprocal circuit device according to claim 7, wherein the laminated first green sheet and second green sheet are pressed. And / or the step of pressing the stacked first green sheet, the second green sheet, and the third green sheet is a step of pressing with hydrostatic pressure.

[0018]

According to the structure of the present invention, unlike the conventional example, the circuit pattern is printed using the printing mask in the state of the green sheet, so that the circuit pattern can be printed without considering the shrinkage of the green sheet. The dimensional design of the pattern printing mask can be performed. Separate the green sheet in which the ferrite disk is to be embedded and the green sheet in which the circuit pattern is to be formed. Laminate the green sheet and align the ferrite disk and the circuit pattern. Therefore, the misalignment between the ferrite disk and the circuit pattern can be prevented.

[0019]

Embodiments of the present invention will be described below with reference to the drawings. First Embodiment FIGS. 1 and 2 are diagrams showing a schematic configuration of a composite substrate type circulator (hereinafter, also simply referred to as a circulator) according to a first embodiment of the present invention. 2 is a cross-sectional view taken along the line AA of FIG. 2, and FIG. 2 is a plan view seen from the direction B of FIG. As shown in FIGS. 1 and 2, this type of circulator has a configuration suitable for operation at a center frequency of 30 GHz, and has a size of 3 mm square and a thickness of about 0.2 mm.
A ferrite disk 1 having a diameter of approximately 1.7 mm is inserted into a first through hole formed in a ceramic plate 16 made of 5 mm alumina.
8 has a ferrite / ceramic composite substrate 102 formed by being fitted therein. Here, a Ni—Zn-based ferrite having a saturation magnetic flux density of 5000 Gauss is used as the material of the ferrite disk 18. On one surface of the ferrite / ceramic composite substrate 102, a first ceramic layer 11 having a thickness of 0.03 mm is laminated with the circuit pattern 103 interposed therebetween.

The circuit pattern 103 is a ferrite disk 1
8 and is formed of a gold film or a silver film, and a portion adjacent to the ferrite disk 18, that is, a diameter of approximately 1.
It has a circular portion 13 of 3 mm. As shown in FIG.
The width is approximately 0.25 in three directions from the circular portion 13 and radially.
mm strip lines 13a, 13b, 13
c extend and terminate at the periphery of the substrate. This terminal is used as input / output terminals 14a, 14b, 14c. In the vicinity of each of the input / output terminals 14a, 14b, 14c,
Open stub / adjustment lands 15a, 15b, 15c are provided separately from the input / output terminals 14a, 14b, 14c.

Further, as shown in FIG.
In portions of the first ceramic layer 11 corresponding to the positions of 4a, 14b, and 14c, holes 12a, 12b, 12
c are formed, and the input / output terminal holes 12a, 12
The input / output terminals 14a, 14b, 14c are exposed in b, 12c. These input / output terminal holes 12a, 12b, 12
The circuit pattern 103 can be connected to another circuit pattern by gold or silver ribbon through c. 3 (a) and 3 (b) show input / output terminals 14a, 14
The arrangement example of b and 14c is shown.

As shown in FIG. 1, a second ceramic layer 19 is laminated on the other surface of the ferrite / ceramic composite substrate 102, and a second ceramic layer 19 on the opposite side of the composite substrate 102 is formed.
On the surface of the ceramic layer 19, a ground conductor layer 20 made of a gold film or a silver film is formed. As described above, according to the form of the circulator, since the circuit patterns 103 and 104 are sandwiched between the ferrite / ceramic composite substrate 102 and the first ceramic layer 11, the film of the circuit patterns 103 and 104 is prevented from peeling. Thus, performance and reliability can be improved.

Next, with reference to FIGS. 4 to 7, a method of manufacturing the above-described composite substrate type circulator will be described. FIG. 4 is a plan view of a large green sheet capable of forming a large number of composite substrates, FIGS. 5 and 6 are process cross-sectional views showing a method of manufacturing a composite substrate type circulator, and FIG. FIG. 7B is a plan view showing the structure of a first green sheet on which a green sheet is formed, and FIG. 7B is a plan view showing the structure of a second green sheet serving as a ferrite / ceramic composite substrate. By the way, when making a ferrite / ceramic substrate, it is necessary to make the diameter of the through hole of the green sheet larger than the diameter of the ferrite in order to fit the ferrite disk into the through hole of the green sheet. When the ferrite is inserted into the through hole, a slight gap occurs between the through hole and the ferrite disk. When a circuit pattern is printed on the surface of such a green sheet using a conductive paste, and the circuit pattern is laminated and pressure is applied, the conductive material constituting the circuit pattern enters the gap. In some cases, the missing conductor may enter the vicinity of the conductor formed on the surface of the other green sheet. In such a state, the electrical impedance deviates from the design value and the input current is reflected, and the circulator does not function. Therefore, it is necessary to adopt a manufacturing method that does not have such a risk.

In the method of manufacturing a circulator / isolator according to this embodiment, first, as shown in FIG. 4, a large number of composite substrates are prepared by preparing a large green sheet 105, but for convenience of explanation. , A small green sheet for one circulator will be described. First, as shown in FIG. 5A, a plate-shaped first green sheet 12a having a thickness after firing of 0.03 mm and a size of 3 mm square is prepared. In this case, as shown in FIG. 7A, input / output terminal holes 12a, 12b, and 12c are formed in portions corresponding to the positions of the input / output terminals.

Next, as shown in FIG. 5A, a conductive film is printed on one surface of the first green sheet 12a using a gold or silver based conductive paste using a printing mask (not shown). Accordingly, in the circuit pattern 103, a portion adjacent to the ferrite disk at the center of the first green sheet 12a shown in FIG. 7A, that is, the circular portion 13 having a diameter of approximately 1.3 mm, and the circular portion 13 Approximately 0.25 m wide from 13 to three sides and radially extending to the periphery of the substrate
m microstrip lines 13a, 13b, 13c
And are formed. Microstrip lines 13a, 13
b, 13c so as to be able to reach the corresponding input / output terminal holes 12a, 12b, 12c.

In this case, the green sheet 11a before firing is used.
Or a circuit pattern 13, 13a, 13 directly on the surface of 11b.
Since b, 13c, or 13 is formed, the print mask does not need to consider the contraction rate of the green sheet 11a or 11b. Next, as shown in FIG. 5A, the first green sheet 11a on which a part of the circuit pattern is formed is set on a stacking jig (not shown) so that the circuit pattern faces upward.

Next, as shown in FIG. 5B, a plate-shaped second green sheet 16a having a first through hole 17 and input / output terminals 14a, 14b, 14c is prepared. The size of the second green sheet 16a is substantially the same as the size of the first green sheet 11a, and when the second green sheet 16a is laminated on the first green sheet 11a, the first through hole 17a is formed. A first through hole 17 is formed so that the circular portion 13 of the circuit pattern of the first green sheet 11a overlaps with the first green sheet 11a. Also, when the second green sheet 16a is laminated on the first green sheet 11a, the end portions of the microstrip lines 13a, 13b, 13c of the first green sheet 11a are partially overlapped and connected. On the second green sheet 16a, input / output terminals 14a, 14b, 14c are formed. Next, as shown in FIG. 5C, the second green sheet 16a is laminated on the first green sheet 11a. At this time, the microstrip lines 13a, 13
b, 13c and input / output terminals 14a, 14b, 1
4c overlaps the tip.

Next, the laminated first green sheet 11a and second green sheet 16a are pressed by applying hydrostatic pressure. At this time, the microstrip line 13
a, 13b, 13c and input / output terminals 14a, 1
The tips of 4b and 14c are crushed and integrated with each other, and a low-resistance connection is realized. Next, as shown in FIG.
A sintered ferrite disk 18 is prepared. Then the first
This first through hole 1 is inserted into the first through hole 17 of the second green sheet 16a laminated on the green sheet 11a of FIG.
Embed a sintered ferrite disk 18 having a diameter slightly smaller than 7.

Next, as shown in FIG. 6A, a plate-shaped third green sheet 19a is prepared, and a gold or silver-based conductive paste is applied to the entire surface of one surface of the third green sheet 19a. Then, the ground conductor layer 20 is formed.
Thereafter, as shown in FIG. 6B, the third green sheet 19a is placed on the second green sheet 19a such that the surface opposite to the surface on which the ground conductor layer 20 is formed faces the second green sheet 19a. It is laminated on the sheet 19a. Next, the stacked first green sheet 11a, second green sheet 16a, and third green sheet 19a are pressed by applying hydrostatic pressure. Next, when the laminated first green sheet 11a, second green sheet 16a, and third green sheet 19a are fired at a predetermined temperature, a composite substrate type circulator is completed. FIG. 2 shows the completed composite substrate type circulator.

As described above, according to the circulator manufacturing method, the first green sheet 11a or 11
(b) Circuit patterns 13, 13 using a printing mask on the surface
After printing a, 13b, 13c or 13 and inserting the ferrite disk 18 into the second green sheet 16a,
First green sheet 11a and second green sheet 1
6a, the ferrite disk 18 and the circular portion 13 of the circuit pattern are aligned. That is, according to this embodiment, unlike the conventional example,
Since the circuit pattern is printed using the printing mask in the state of the green sheet, the dimension design of the circuit pattern printing mask can be performed without considering the shrinkage ratio of the green sheet.

The ferrite disk 18 and the circuit patterns 13, 13a, 13b, 13c are formed on separate green sheets 11a, 16a.
6a, the ferrite disk 18 and the circular portion 13 of the circuit pattern are aligned, and then fired. Therefore, it is easy to set the laminated green sheets 11a and 16a to the same firing temperature at the time of firing. Therefore, when the green sheets having the same material composition are used, the stacked green sheets 11a and 16a are the same at the time of firing. The firing temperature is reached, and the same shrinks based on the material composition. Therefore, as shown in FIG. 8, the ferrite disk 18 and the circuit patterns 13, 13a, 13b, 13c
Misalignment can be prevented. Therefore, planar processing polishing can be omitted, and the circulator can be realized at low cost.

If the same composition is used as much as possible, the shrinkage ratio of the green sheet during firing does not vary, so that the composition range of the green sheet is not limited. On the other hand, in the case of the conventional example, since the range of the shrinkage rate is limited, it is necessary to limit the composition range.
Also, instead of the surface of the ferrite / ceramic composite substrate 102 on which the uneven surface of the ferrite disk 18 is exposed, a circuit pattern 1 is formed on ceramic green sheets 11a, 16a, and 19a on which a flat surface is easily formed.
Since 3, 13a, 13b, and 13c are printed, variations in the film thickness of the circuit patterns 13, 13a, 13b, and 13c and film peeling can be prevented.

Second Embodiment FIG. 9 is a plan view showing a schematic configuration of a composite substrate type isolator (hereinafter, simply referred to as an isolator) according to a second embodiment of the present invention. The difference between the isolator of this embodiment and the circulator of the first embodiment is that the circulator has microstrip lines 13a, 13b, 13b as shown in FIG.
c is used as input / output terminals 14a, 14b, and 14c. In this isolator, as shown in FIG.
a, 13b, and 13c are configured such that any two of them are used as input / output terminals 14a and 14b, and the other one is used as a connection terminal 14c of the terminating resistor 24; The microstrip line 13d extends further toward the end than the 24 connection terminals 14c, and terminates as the input terminal 14d.

Accordingly, in this isolator, instead of the input / output terminal 14c, the input / output terminal hole 1 is formed in the portion of the first ceramic layer 11 corresponding to the position of the input / output terminal 14d.
2d is formed, and the input / output terminal 14d and the adjustment land 15d are exposed in the input / output terminal hole 12d. In addition, the terminal 1 of the microstrip line 13c
In the first ceramic layer 11 at a position corresponding to the position 4c, a termination resistor connection hole 23 is provided.

The circuit pattern 104 of the isolator
Has impedance adjustment patterns 22a, 22b, and 22c as shown in the figure, and the first ceramic layer 11 at a position corresponding to the position of the impedance adjustment patterns 22a, 22b, and 22c has an impedance adjustment pattern. Holes 21a, 21b, 21c are provided. Thereby, the impedance adjusting holes 21a, 21b, 21c are formed.
Through the impedance adjustment patterns 22a, 22
b, 22c, and the impedance adjusting holes 21a,
The impedance of the circuit can be adjusted through 21b and 21c. In the circuit pattern 103 of the circulator, the impedance adjustment patterns 22a, 22b, and 22c may be provided at the same positions.

In other respects, the structure of this isolator is substantially the same as that of the circulator shown in FIG. 2, and therefore, in FIG. 9, the same parts as those in FIG. , The description of which is omitted. When the isolator having the above configuration is manufactured, the first green sheet 11b is previously provided with only the circular portion 13 of the circuit pattern adjacent to the ferrite disk, as shown in FIG. The input / output terminal holes 12a, 12b, 12d are formed in portions corresponding to the positions of the input / output terminals.
In addition to the above, a hole 23 for terminating resistance connection and holes 21a, 21b, 21c for impedance adjustment are formed in advance. As shown in FIG. 2B, the second green sheet 16b has a first through hole 17 and a microstrip line 1 formed therein.
3a, 13b, and 13c, and input / output terminals 14a, 14b, and 14c that extend to the end of each terminal are formed in advance. In this case, the microstrip line 13
When the second green sheet 16b is laminated on the first green sheet 11b, the circular portion 13 of the first green sheet 11b and the microstrip line 13a of the second green sheet 16b , 1
The tips of 3b and 13c are arranged so as to overlap each other.

In this manner, when the first green sheet 11b and the second green sheet 16b are pressed and laminated, the circular portion 13 and the microstrip line 1
Since the tip portions 3a, 13b, and 13c are crushed and integrated with each other, a low-resistance connection can be realized. The other manufacturing procedures are substantially the same as the circulator manufacturing procedure described in the first embodiment. As described above, according to this embodiment, substantially the same effects as those of the above-described first embodiment can be obtained.

Third Embodiment FIG. 11 is a plan view showing a composite substrate type circulator according to a third embodiment of the present invention.
FIG. 4 is an explanatory cross-sectional view for explaining a method of manufacturing the circulator. The difference between the circulator of this embodiment and the first embodiment is that, as shown in FIG. 11, a second through-hole 26 is provided in the second ceramic Embedded conductor layer 27
Is embedded so that the buried conductor layer 27 and the ferrite disk 18 are directly adjacent to each other when they are stacked.
In this case, since the insertion loss is suppressed, the characteristics of the ferrite disk 18 can be fully utilized. Next, FIG.
, A method of manufacturing the circulator of this embodiment will be described. First, the ferrite disk 18 sintered in the first through hole 17 of the second green sheet 16a laminated on the first green sheet 11a through the same steps as those shown in FIGS. Inset. Next, FIG.
As shown in (a), a plate-like third green sheet 25
a is prepared, and a second through hole 26 having a diameter smaller than that of the ferrite disk 18 is formed. Next, as shown in FIG. 12B, a conductive paste 28 is applied to one surface of the third green sheet 25a, and the conductive paste 28 is embedded in the second through holes 26.

Subsequently, the surface opposite to the surface on which the conductive paste 28 is applied faces the second green sheet 16a laminated on the first green sheet 11a, and the second through hole 26 is formed of a ferrite disk. The third green sheet 25a is laminated on the second green sheet 16a so as to be on the second green sheet 16a. Next, the laminated first green sheet 11a
Then, the second green sheet 16a and the third green sheet 25a are pressed by hydrostatic pressure. Next, FIG.
As shown in (c), the laminated first green sheet 11a, second green sheet 16a, and third green sheet 25a are fired. The conductor paste 28 in the second through hole 26 becomes the buried conductor layer 27, and the conductor paste 28 on the ceramic layer 25 becomes the ground conductor layer 20 in contact with the buried conductor layer 27. Thus, the composite substrate type circulator is completed.

As described above, according to the circulator manufacturing method of this embodiment, substantially the same effects as those described in the first embodiment can be obtained. By using the circuit pattern 104 shown in FIG. 9, an isolator having the same basic structure as the circulator of this embodiment can be formed.

Fourth Embodiment FIGS. 13 and 15 are diagrams showing a schematic configuration of a composite substrate type isolator (hereinafter, simply referred to as an isolator) according to a fourth embodiment of the present invention. Specifically, FIG.
Is a cross-sectional view taken along line CC of FIG. 15, and FIG.
16A is a plan view showing a configuration of a first ceramic substrate used for manufacturing the isolator, and FIG. 16B is a plan view showing a configuration of a second ceramic substrate. FIG. 3 is a plan view illustrating a configuration of a substrate. The isolator of this embodiment differs greatly from the isolator of the second embodiment in that a circuit pattern 104 is formed on the surface of the first ceramic layer 29 opposite to the composite substrate 16 as shown in FIGS. The point is that it is formed. In this case, the circular portion 13 of the circuit pattern is formed on the ferrite disk 18 via the first ceramic layer 29.

In the manufacturing method of the isolator of this embodiment,
As shown in FIG. 16A, all the circuit patterns 104
Is formed on the first green sheet 29a, FIG.
As shown in (b), the point that only the first through hole 17 is formed in the second green sheet 16a, and the circuit pattern 1
The second embodiment is substantially the same as the first embodiment except that the second green sheet 16a and the first green sheet 29a are laminated so that the substrate 04 faces the opposite side to the second green sheet 16a serving as the composite substrate. Go through the process. That is, the first green sheet 29a on which the circuit pattern 104 is printed → the second green sheet 16a to be a composite substrate → hydrostatic pressing → the ferrite disk 18 on the second green sheet 16a
The isolator is formed according to a stacking procedure of fitting, a third green sheet on which the ground conductor layer 20 is printed, and a hydrostatic press. The circulator can be formed in substantially the same manner as described above, except that all the circuit patterns 103 are formed on the first green sheet 29a.

As described above, according to the isolator of this embodiment, since the circuit pattern 104 or 103 is formed on the surface of the first ceramic layer 29 opposite to the ferrite / ceramic composite substrate 16, the properties of the material itself Since it is not necessary to form the circuit pattern 104 or 103 on the surface of the ferrite disk 18 having an uneven upper surface, it is possible to prevent variations in the film thickness of the circuit pattern 104 or 103 due to the surface unevenness and to improve the performance. Can be improved.

Fifth Embodiment FIG. 14 is a sectional view showing a schematic configuration of an isolator according to a fifth embodiment of the present invention. In the isolator of this embodiment, as shown in the figure, a ground conductor layer 20 is formed on the surface of the second ceramic layer 19 opposite to the composite substrate 16.
The second embodiment is different from the second embodiment in that the second through hole 26 is formed in the second ceramic layer 19 and the buried conductor 27 that comes into contact with the ground conductor layer 20 is buried. It is substantially the same, except that the circuit pattern 104 is formed on the surface of the first ceramic layer 30 opposite to the composite substrate 16 and the third through hole 31 is formed in the first ceramic layer 30. The difference from the second embodiment is that the embedded conductor 32 that is in contact with the circuit pattern 104 is embedded. In this case, the buried conductors 32 and 27 are adjacent to the ferrite disk 18 when they are stacked, so that insertion loss is suppressed as much as possible.

In the method of manufacturing an isolator of this embodiment, all the circuit patterns 104 are formed as shown in FIG.
The first green sheet 30a shown in FIG. 6A is replaced with the circuit pattern 104 by the second green sheet 16 serving as a composite substrate.
16A, the point that only the first through hole 17 is formed in the second green sheet 16a as shown in FIG. 16B, and the circuit pattern 104 of the first green sheet 30a. In the position of the circular portion 13 of the third through hole 3
1 is formed through the same steps as in the second embodiment, except that the step 1 is formed. That is, the first green sheet 30a on which the circuit pattern 104 is printed → the second green sheet 16a to be a composite substrate → hydrostatic pressing → the fitting of the ferrite disk 18 into the second green sheet 16a → the ground conductor layer 20 A composite substrate type isolator is prepared according to a lamination procedure of a printed third green sheet → a hydrostatic press. Thus, according to the isolator of this embodiment, substantially the same effects as described in the fourth embodiment can be obtained.

<Comparative Experiment> Next, isolators having the configurations shown in FIGS. 9, 11, 13 and 14 were prepared according to the second to fifth embodiments, respectively, and the isolator characteristics were measured.
However, in FIG. 11, the circuit pattern 104 of the isolator shown in FIG. 9 was used as the circuit pattern. N
o. 1 to No. Six types of six samples were prepared, and 500 samples of each of these were prepared. No. 1 to No. 6
Of the samples of No. 1 to No. Sample No. 4 has the configuration shown in FIGS. 9, 11, 13 and 14, respectively, and was prepared by the lamination procedure of the second to fifth embodiments. That is, a first green sheet on which a circuit pattern is printed → a second green sheet serving as a composite substrate → a hydrostatic press → fitting of a ferrite disk into the second green sheet → a third green printed with a ground conductor layer Sheets were prepared according to a lamination procedure of hydrostatic pressing. In addition, No. 1 to No. No. 6 among the samples No. 6
5 and No. 5 6 is a comparative sample. No. 5 and No. 5
6 has the configuration of FIGS. 9 and 11, respectively. However, in FIG. 11, the circuit pattern 104 of the isolator shown in FIG. 9 was used as the circuit pattern. And it laminate | stacked by the lamination | stacking procedure reverse to the said embodiment. That is, the third green sheet printed with the ground conductor layer →
The second green sheet to be a composite substrate → Hydrostatic press →
Insert ferrite disk into second green sheet →
It was prepared according to a lamination procedure of a first green sheet on which a circuit pattern was printed → hydrostatic pressing.

In the measurement, a permanent magnet (not shown) having a maximum BH product of 28 MGOe having a diameter of 1.8 mm and a height of 4 mm was arranged with a gap of about 100 μm above the circular portion of the circuit pattern, and as shown in FIG. The termination of the microstrip line was terminated with a 50Ω chip resistor (termination resistor) 24. Table 1 shows the average values of the operating frequency and the insertion loss.

[0048]

[Table 1]

Although the embodiments of the present invention have been described in detail with reference to the drawings, the specific configuration is not limited to the embodiments, and there may be design changes within the scope of the present invention. Even this is included in the present invention. For example, in the above embodiment, alumina is used as the material of the ceramic plate and the ceramic layer, but other types of ceramics may be used. Further, a gold-based or silver-based conductive film is used as a material of the circuit pattern and the ground conductor layer, but another type of conductive film may be used. Further, a method of printing a conductive paste is used as a method of forming a circuit pattern and a ground conductor layer, but other methods such as vapor deposition may be used. Although the opening for impedance adjustment and the hole for connecting the terminating resistor are formed in the first ceramic layer, they may be formed in the second ceramic layer and the composite substrate. Furthermore, when pressing the green sheet, the hydrostatic pressure is applied, but pressure may be applied from above and below the green sheet.

[0050]

As described above, according to the embodiment of the present invention, since the circuit pattern is printed using the printing mask in the state of the green sheet, the shrinkage ratio of the green sheet is not taken into consideration. The dimension of the circuit pattern printing mask can be designed. Also, since the ferrite disk and circuit pattern are formed on separate green sheets, laminated in the state of the green sheet, the ferrite disk and the circuit pattern are aligned, and then fired,
At the time of firing, both the laminated green sheets have the same firing temperature and shrink in the same manner based on the material composition, thereby preventing the misalignment between the ferrite disk and the circuit pattern.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a schematic configuration of a circulator according to a first embodiment of the present invention.

FIG. 2 is a plan view showing the configuration of the circulator as viewed from a direction B in FIG.

FIG. 3 is a plan view showing an arrangement of input / output terminals of the circulator.

FIG. 4 is a view for explaining a method of manufacturing the circulator, and is a plan view showing a configuration of a large green sheet.

FIG. 5 is an explanatory cross-sectional view for explaining a method of manufacturing the circulator.

FIG. 6 is an explanatory cross-sectional view for explaining a method of manufacturing the circulator.

FIG. 7A is a plan view showing a configuration of a first ceramic substrate used for manufacturing the circulator, and FIG. 7B is a plan view showing a configuration of a second ceramic substrate.

FIG. 8 is a plan view of a circulator produced by the same manufacturing method, in which pattern displacement hardly occurs.

FIG. 9 is a plan view showing a schematic configuration of an isolator according to a second embodiment of the present invention.

FIG. 10A is a plan view showing a configuration of a first ceramic substrate used in a method for manufacturing the isolator, and FIG. 10B is a plan view showing a configuration of a second ceramic substrate.

FIG. 11 is a sectional view showing a schematic configuration of a circulator according to a third embodiment of the present invention.

FIG. 12 is an explanatory cross-sectional view for explaining a method of manufacturing the circulator.

FIG. 13 is a sectional view showing a schematic configuration of an isolator according to a fourth embodiment of the present invention.

FIG. 14 is a sectional view showing a schematic configuration of an isolator according to a fifth embodiment of the present invention.

FIG. 15 is a plan view seen from a direction D in FIG. 13;

FIG. 16A is a plan view showing a configuration of a first ceramic substrate used for manufacturing an isolator according to a fourth embodiment of the present invention, and FIG. 16B is a configuration of a second ceramic substrate. FIG.

FIG. 17 shows a conventional circuit board type circulator /
It is explanatory sectional drawing for demonstrating the manufacturing method of an isolator.

FIG. 18 is a plan view showing a state of pattern misregistration generated in the composite substrate type circulator produced by the circulator manufacturing method.

[Explanation of symbols]

11, 29, 30 First ceramic layer 11a, 29a, 30a First green sheet 12a, 12b, 12c, 12d Input / output terminal hole 13 Circular portion (partial circuit pattern adjacent to ferrite disk) 13a, 13b, 13c, 13d Microstrip line (circuit pattern) 14a, 14b, 14c, 14d Input / output terminal (circuit pattern) 16 Ceramic plate 16a Second green sheet 17 First through hole 18 Ferrite disk 19, 25 Second ceramic Layer 19a Third green sheet 20 Ground conductor layer 21a, 21b, 21c Impedance adjustment hole 22a, 22b, 22c Impedance adjustment pattern 23 Termination resistor connection hole 24 Termination resistor 26 Second through hole 27, 32 Embedded conductor Layer 31 Third through hole 102 Composite substrate 103 and 104 circuit pattern

────────────────────────────────────────────────── ─── Continuation of the front page (72) The inventor Kazuhiro Ikume 5-7-1 Shiba, Minato-ku, Tokyo Within NEC Corporation (56) References JP-A-8-65013 (JP, A) JP-A Heihei 8-204408 (JP, A) JP-A-50-50843 (JP, A) JP-A-8-162806 (JP, A) JP-A-8-102603 (JP, A) Japanese Utility Model Publication No. 56-176501 (JP, A) U) (58) Field surveyed (Int.Cl. ⁷ , DB name) H01P 1/387 H01P 1/36 H01P 11/00 H05K 1/18

Claims (8)

(57) [Claims] 1. A composite substrate in which a ferrite disk is embedded in a first through hole of a ceramic plate, and laminated on one surface of the composite substrate with a circuit pattern having a portion adjacent to the ferrite disk interposed therebetween. A first ceramic layer,
A composite substrate type non-reciprocal circuit comprising: a ground conductor layer formed on the other surface side of the composite substrate; and a second ceramic layer interposed between the ground conductor layer and the composite substrate. The element, wherein the second ceramic layer has a diameter smaller than the diameter of the ferrite disk, a second through hole adjacent to the ferrite disk is formed, and A composite substrate type non-reciprocal circuit device, characterized in that a buried conductor layer in contact with the ground conductor layer is buried in the through hole. 2. A circuit board according to claim 1, wherein said circuit pattern extends from a portion adjacent to said ferrite disk toward an end of said composite substrate, and an input / output terminal is formed at a terminal end thereof. 2. The composite substrate type non-volatile memory according to claim 1, wherein an input / output terminal hole is formed in said first ceramic layer, and said input / output terminal is exposed in said input / output terminal hole. Reversible circuit element. 3. The method according to claim 1, wherein the circuit pattern has an impedance adjustment pattern, and an impedance adjustment hole is formed in a portion of the first ceramic layer corresponding to a position of the impedance adjustment pattern. The composite substrate type non-reciprocal circuit device according to claim 1 or 2, wherein the impedance adjustment pattern is exposed in the adjustment hole. 4. The semiconductor device according to claim 1, wherein the circuit pattern has a terminal resistor connection portion, and a terminal resistor connection hole is formed in a portion of the first ceramic layer corresponding to the connection position. 4. The composite substrate type non-reciprocal circuit device according to claim 1, wherein a connection portion of said terminating resistor is exposed. 5. A composite substrate in which a ferrite disk is embedded in a first through hole of a ceramic plate; a first ceramic layer laminated on one surface of the composite substrate;
A circuit pattern formed on the surface of the ceramic layer opposite to the composite substrate so that at least a portion thereof is above the ferrite disk; and a ground conductor layer formed on the other surface of the composite substrate. A composite substrate type non-reciprocal circuit device comprising: a ground conductor layer; and a second ceramic layer interposed between the composite substrate, wherein the second ceramic layer includes the ferrite. A second through hole having a diameter smaller than the diameter of the disk and adjacent to the ferrite disk is formed, and an embedded conductor layer that is in contact with the ground conductor layer is embedded in the second through hole. A composite substrate type non-reciprocal circuit device characterized by being characterized in that: 6. The first ceramic layer has a diameter smaller than the diameter of the ferrite disk, a third through hole adjacent to the ferrite disk is formed, and the third through hole is formed. 6. The composite substrate type non-reciprocal circuit device according to claim 5, wherein a buried conductor layer that is in contact with a part of the circuit pattern is buried in the hole. 7. A step of placing a plate-shaped first green sheet having a circuit pattern formed on one surface such that the circuit pattern faces upward or downward; and a plate having a first through hole. -Shaped second green sheet,
Stacking on the first green sheet such that at least a part of the circuit pattern and the first through hole are adjacent directly or via the first green sheet; and Pressing a first green sheet and a second green sheet, and embedding a sintered ferrite disk in a first through hole of the second green sheet laminated on the first green sheet. And a ground conductor layer formed on one surface, and a buried conductor layer in contact with the ground conductor layer is embedded in a second through hole having a diameter smaller than that of the ferrite disk.
The second green sheet so that the surface opposite to the surface on which the ground conductor layer is formed faces the second green sheet, and the buried conductor layer is on the ferrite disk. A step of pressing the stacked first green sheet, the second green sheet, and the third green sheet; a step of pressing the stacked first green sheet, the second green sheet, and the third green sheet; And a step of baking the third green sheet and a third green sheet. 8. A step of pressing the stacked first green sheet and the second green sheet, and / or a step of pressing the stacked first green sheet, the second green sheet, and the third green sheet. The method for manufacturing a composite substrate type non-reciprocal circuit device according to claim 7, wherein the step of pressing the sheet is a step of pressing with a hydrostatic pressure.