JPH0884007A - Strip line type coupler - Google Patents

Abstract

PURPOSE: To improve the degree of coupling with a simple constitution. CONSTITUTION: A band-shaped groove is formed on the upper face of a substrate 1, and a shield conductor 4 like a sheet is formed so as to cover at least side faces and the bottom face of this groove. A dielectric is embedded in the groove with the shield conductor 4 between them. A pair of strip lines 3 are arranged in parallel along the upper face of a dielectric layer 5 formed by embedding the dielectric. The dielectric layer 5 is made of the dielectric having a dielectric constant higher than that of the substrate 1, and preferably, it is made of a high dielectric material like a barium titanate. Since a part or the substrate 1 is substituted with the dielectric layer 5 having a desired high dielectric constant, restrictions on materials of the substrate and requirements for rise of the degree of coupling are satisfied together. Further, the dielectric layer 5 having the high dielectric constant is used to give a simple constitution to strip lines. Thus, the high degree of coupling is obtained with the simple constitution.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a strip line type coupler suitable for coupling electromagnetic signals in the microwave and millimeter wave bands, and more particularly to an improvement for increasing the degree of coupling with a simple structure.

[0002]

2. Description of the Related Art Conventionally, a strip line has been used as one of couplers for coupling electromagnetic signals in a microwave and a millimeter wave (abbreviated as "MM wave" for convenience in this specification) band. Stripline couplers are known. FIG. 19 is a front sectional view showing a typical example of the configuration of this conventional stripline coupler. In FIG.
Reference numeral 1 is a substrate made of a dielectric material such as ceramic, silicon, GaAs or a semiconductor, 2 is a conductor, and is a sheet-like ground conductor provided on the lower surface of the substrate 1 for transmitting a ground potential, and 3 Is two strip lines which are made of strip-shaped conductors and are arranged in parallel to each other on the upper surface of the substrate 1.

In this coupler, two strip lines 3
Electromagnetic signals are exchanged between them. As shown in FIG. 19, the stripline coupler has a simple structure and therefore has an advantage of being easy to manufacture. For this reason, in particular,
Along with a transistor and other active elements, it is often used as a coupler built in a semiconductor integrated circuit for MM wave band (so-called "MMIC").

[0004]

However, since the stripline coupler is an edge-coupled type in which the edges of the stripline 3 are coupled to each other, the coupling is weak (that is, the degree of coupling is low). It was As a solution to this problem, an interdigital stripline coupler has been introduced, and this type of MMIC is exclusively used.

FIG. 20 is a top view showing an example of a conventional interdigital coupler. This coupler is shown in FIG.
As shown in, the strip lines 3a and 3b are formed in the shape of fine comb teeth and are arranged so that one comb tooth is inserted between the other comb teeth. Further, a jumper wire W is connected to the tips of the comb teeth.

As described above, since the structure of the interdigital coupler is minute and complicated, it causes a new problem that it is difficult to manufacture. This diminishes the inherent simplicity of the stripline coupler. In addition, since the fine structure is required, the resistance component of the strip line increases, which causes a problem that the circuit characteristics of the coupler deteriorate.

The present invention has been made in order to solve the above-mentioned problems in the conventional strip line type coupler, and the strip line type coupling which has a simple structure and has a strong coupling and whose resistance component can be sufficiently lowered. The purpose is to provide a container.

[0008]

A stripline coupler according to a first aspect of the present invention is a stripline coupler for coupling an electromagnetic signal, wherein a groove is formed on the upper surface of a substrate, and the groove is formed in the groove. A dielectric layer having a higher dielectric constant than that of the substrate is embedded, and a plurality of strip lines are arranged in the dielectric layer.

A stripline coupler according to a second invention is characterized in that, in the first invention, the plurality of striplines are arranged on an upper surface of the dielectric layer.

A stripline coupler according to a third invention is characterized in that, in the first invention, the plurality of striplines are embedded in the dielectric layer.

A stripline coupler according to a fourth aspect of the present invention is the stripline coupler according to the third aspect, wherein each of the plurality of striplines has a strip plate shape, and the main surfaces thereof face each other. It is characterized by being buried in the body layer.

In a strip line type coupler according to a fifth aspect of the present invention, in the first aspect of the present invention, a sheet-shaped shield conductor is formed on the substrate so as to cover the inner wall of the groove,
The dielectric layer is embedded in the groove via the shield conductor.

A stripline type coupler according to a sixth aspect of the present invention is the stripline type coupler according to the fifth aspect, wherein a sheet-like ground conductor is provided on the lower surface of the substrate, and the ground conductor and the shield conductor are electrically connected to each other. It is characterized by being connected.

A stripline coupler according to a seventh invention is the stripline coupler according to the sixth invention, wherein a through hole is formed in the substrate so as to penetrate the bottom surface of the groove and the lower surface of the substrate.
The shield conductor and the ground conductor are electrically connected by a conductor foil formed on the inner wall of the through hole.

In a strip line type coupler according to an eighth aspect of the present invention, in the first aspect of the present invention, the substrate has a metal layer in at least an upper layer portion thereof, and the groove is formed on an upper surface of the metal layer. Is characterized by.

A stripline coupler according to a ninth invention is characterized in that, in the first invention, a shield conductor for covering the plurality of striplines is provided on the substrate.

A stripline coupler according to a tenth invention is the stripline coupler according to the fifth invention, wherein
A second shield conductor that covers the plurality of strip lines is provided on the substrate, and the first and second shield conductors have their ends connected to each other. Jointly cover the entire circumference of the plurality of strip lines.

A stripline type coupler according to an eleventh invention is the stripline coupler according to the sixth invention, wherein
A second shield conductor that covers the plurality of strip lines is provided on the substrate, and the first and second shield conductors have their ends connected to each other. Jointly cover the entire circumference of the plurality of strip lines.

In the stripline coupler according to the twelfth invention, in the eighth invention, a shield conductor covering the plurality of striplines is provided on the substrate, and the shield conductor has an end portion. By being connected to the metal layer, both the shield conductor and the metal layer jointly cover the entire circumference of the plurality of strip lines.

A stripline coupler according to the thirteenth invention is the stripline coupler according to the ninth or twelfth invention, wherein the inner cavity of the shield conductor is filled with a dielectric having a higher dielectric constant than that of the substrate. Is characterized by.

The stripline coupler according to the fourteenth invention is the stripline coupler according to the tenth or eleventh invention.
The inner cavity of the shield conductor is filled with a dielectric material having a higher dielectric constant than that of the substrate.

A stripline coupler according to the fifteenth invention is characterized in that, in the first invention, the dielectric layer comprises a high dielectric material.

In the strip line type coupler according to the sixteenth invention, in the first invention, each width of the plurality of strip lines is individually adjusted so as to realize a required characteristic impedance. It is characterized by

A stripline type coupler according to a seventeenth aspect of the present invention is the stripline type coupler for coupling an electromagnetic signal according to the first aspect, wherein a plurality of grooves are formed on the upper surface of the substrate. A dielectric layer having a higher dielectric constant than that of the substrate is embedded in the plurality of grooves, and a plurality of strip lines are provided for each of the dielectric layers, so that each functions as a single coupler. It is characterized in that a plurality of unit couplers are configured.

In the stripline type coupler according to the eighteenth invention, in the seventeenth invention, the shape of the groove and the shape of the stripline are common between the plurality of unit couplers. The body layer is configured by individually selecting materials having a required dielectric constant according to the degree of coupling required for each unit coupler.

A stripline type coupler according to the nineteenth invention is a stripline type coupler for coupling an electromagnetic signal, wherein a groove is formed on the upper surface of the substrate, and the sheet is formed so as to cover the inner wall of the groove. -Shaped shield conductor is formed on the substrate, the dielectric layer is embedded in the groove through the shield conductor, and a plurality of strip lines are arranged in the dielectric layer. Characterize.

A stripline coupler according to a twentieth aspect of the invention is a stripline coupler for coupling an electromagnetic signal, characterized in that a plurality of striplines are embedded in a substrate.

In the present invention, the "strip line type coupler" includes not only a device used alone as a coupler but also a coupler formed together with other circuit elements in an integrated circuit. To do.

[0029]

In the stripline type coupler of the first aspect of the invention, since the stripline is arranged in the dielectric layer having a higher dielectric constant than the substrate, the restrictions on the material of the substrate can be satisfied, To obtain the desired high degree of binding.

In the stripline type coupler of the second invention, the stripline is arranged on the upper surface of the dielectric layer, and therefore the stripline can be easily arranged.

In the strip line type coupler of the third invention, since the strip line is embedded in the dielectric layer,
The degree of coupling between the strip lines is further enhanced.

In the strip line type coupler of the fourth aspect of the present invention, each of the plurality of strip lines has a strip plate shape and is embedded in the dielectric layer so that its main surfaces face each other. The areas of these strip lines facing each other are large. This results in stronger coupling between the stripline lines.

In the strip line type coupler of the fifth invention, the sheet-like shield conductor is formed on the substrate so as to cover the inner wall of the groove, and the dielectric layer is embedded in the groove through the shield conductor. There is. That is, the structure is as if the shield conductor were formed around the dielectric layer. For this reason, the electromagnetic waves radiated from the strip line are confined inside the shield conductor, and the electromagnetic wave energy that would otherwise be lost by radiation also contributes to the coupling. As a result, the coupling between the strip lines is further strengthened.

In the strip line type coupler of the sixth aspect of the invention, since the shield conductor and the ground conductor are electrically connected, the shield conductor also has a function of suppressing the intrusion of electromagnetic waves from the outside into the strip line. Therefore, the stability of the signal transmission characteristic of the coupler is enhanced.

In the stripline type coupler of the seventh invention, the shield foil and the ground conductor are electrically connected by the conductor foil formed on the inner wall of the through hole penetrating the bottom surface of the groove and the bottom surface of the substrate. ing. Therefore, before the shield conductor and the dielectric layer are embedded in the groove formed in the substrate, the through hole and the conductor foil are formed in the substrate in advance, so that the shield conductor is formed at the same time as the shield conductor and the ground conductor. A short circuit is realized. That is, in this coupler, an electrical short circuit between the shield conductor and the ground conductor is realized by a simple process.

In the stripline type coupler of the eighth invention, the metal layer is present in at least the upper layer portion of the substrate, and the groove for burying the dielectric layer is formed on the upper surface of the metal layer. Since this metal layer can also function as a ground conductor, both effects of improving the coupling degree by the confinement effect of electromagnetic energy and stabilizing the signal transmission characteristic by the shielding effect of electromagnetic noise are brought about by the metal layer. .

In the stripline type coupler of the ninth invention, a shield conductor for covering the plurality of striplines is provided on the substrate. Therefore, the electromagnetic waves emitted from the strip line are confined inside the shield conductor.
As a result, the electromagnetic energy that would otherwise be lost by radiation also contributes to the coupling, thus further strengthening the coupling between the strip lines.

In the stripline type coupler of the tenth aspect of the invention, the first and second shield conductors cover the entire circumference of the stripline, so that the effect of confining electromagnetic waves is further enhanced.

In the strip line type coupler of the eleventh invention, the first and second shield conductors cover the entire circumference of the strip line, and the shield conductors and the ground conductors are electrically connected. Therefore, the effect of suppressing the intrusion of electromagnetic waves from the outside into the strip line is further enhanced.

In the stripline type coupler of the twelfth aspect of the invention, since the entire circumference of the stripline is covered by the metal layer and the shield conductor, the effect of confining electromagnetic waves is further enhanced. Furthermore, since the metal layer and the shield conductor are connected to each other, the effect of suppressing the intrusion of electromagnetic waves from the outside into the strip line is further enhanced.

In the stripline type coupler of the thirteenth invention, since the inner cavity of the shield conductor is filled with a dielectric material having a higher dielectric constant than the substrate, the stripline is composed of
It is as if it were embedded in a substance having a higher dielectric constant than the substrate. Therefore, the degree of coupling between the strip lines is further increased.

In the stripline type coupler of the fourteenth invention, since the inner cavity of the second shield conductor is filled with a dielectric material having a higher dielectric constant than the substrate, the stripline has a dielectric constant higher than that of the substrate. It is as if it were buried in a high-quality material. Therefore, the degree of coupling between the strip lines is further increased.

In the strip line type coupler of the fifteenth invention, since the dielectric layer has a high dielectric material, the degree of coupling between the strip lines is further increased.

In the strip line type coupler of the sixteenth aspect of the invention, the width of each of the plurality of strip lines is individually adjusted so as to realize the required characteristic impedance. We can also meet your requirements.

In the strip line type coupler of the seventeenth invention, a plurality of grooves are formed in the substrate, and a plurality of unit couplers are provided corresponding to each groove. That is,
It functions as a kind of integrated circuit with multiple unit couplers on a single substrate.

In the strip line type coupler of the eighteenth invention, the plurality of unit couplers have the same shape, so that they are easy to manufacture. Moreover, since the material of the dielectric layer is individually selected among the unit couplers based on the demand for the degree of coupling, it is possible to meet the demand for the degree of coupling different for each unit coupler.

In the strip line type coupler of the nineteenth invention, a sheet-shaped shield conductor is formed so as to cover the inner wall of the groove formed on the upper surface of the substrate. Therefore, the effect of confining the electromagnetic energy by the shield conductor functions to improve the coupling degree.

In the strip line type coupler of the twentieth invention, since the plurality of strip lines are embedded in the substrate, the coupling between these strip lines is strengthened.

[0049]

【Example】

<First Embodiment> FIG. 1 is a perspective view showing the overall structure of a stripline coupler according to the first embodiment. 2 is shown in FIG.
4 is a front sectional view of the coupler shown in FIG. In the following figures, the same parts as those of the conventional device shown in FIG. 19 are designated by the same reference numerals and detailed description thereof will be omitted.

As shown in FIGS. 1 and 2, in this coupler, a band-shaped groove is formed on the upper surface of the substrate 1, and the sheet-shaped shield conductor 4 is formed so as to cover at least the side surface and the bottom surface of the groove. Has been formed. Then, a dielectric is embedded in the groove via the shield conductor 4. The pair of strip lines 3 are arranged parallel to each other along the upper surface of the embedded dielectric layer 5.

The ground conductor 2, the strip line 3, and the shield conductor 4 are made of an electrically conductive material, for example, a metal such as aluminum or copper. The substrate 1 is made of, for example, a dielectric material such as ceramic, silicon, GaAs, or a semiconductor. Particularly, when this coupler constitutes a monolithic MMIC together with an active element such as a transistor, the substrate 1 is constituted by a semiconductor such as silicon or GaAs. On the other hand, the dielectric layer 5 is composed of a dielectric material having a higher dielectric constant than the substrate 1, and particularly preferably a high dielectric material such as barium titanate.

In this coupler, since the dielectric constant of the dielectric layer 5 which is a medium located directly below the strip line 3 is higher than that of the substrate 1, the conventional strip line 3 is directly disposed on the substrate 1. The coupling between the strip lines 3 is higher than that of the coupler (FIG. 19). The material forming the substrate 1 should be selected in consideration of the mechanical strength of the coupler, the workability of the material, the price, etc., and can be selected only from the dielectric constant that determines the degree of coupling between the strip lines 3. is not. In particular, a high dielectric substance typified by barium titanate is a brittle material and is not suitable for the material of the substrate 1. Furthermore, when the coupler is incorporated in a monolithic MMIC, the material of the substrate 1 is limited to semiconductors.

In the coupler of this embodiment, a part of the substrate 1 is replaced with a dielectric layer 5 having a desired high dielectric constant, so that the restriction on the material of the substrate 1 and the demand for increasing the coupling degree are compatible with each other. Has been realized. Moreover, by using the dielectric layer 5 having a high dielectric constant, the strip line 3 can have a simple structure similar to that of the conventional device shown in FIG. Therefore, in this coupler, the desired high degree of coupling can be realized without increasing the resistance component while maintaining the simple structure and the ease of manufacturing which the stripline type coupler originally has.

Furthermore, since the shield conductor 4 is formed around the dielectric layer 5, the electromagnetic waves emitted from the strip line 3 are confined inside the shield conductor 4.
Therefore, the electromagnetic wave energy that is originally lost by radiation also contributes to the coupling. As a result, the coupling between the strip lines 3 is further strengthened.

Both the shield conductor 4 and the dielectric layer 5 are provided by utilizing the groove formed in the substrate 1. That is, the coupler of this embodiment including both the shield conductor 4 and the dielectric layer 5 effectively uses the groove to increase the degree of coupling.

The shield conductor 4 may be electrically connected to the ground conductor 2 by a jumper wire (not shown). At this time, the shield conductor 4 also has a function of suppressing the intrusion of electromagnetic waves from the outside into the strip line 3, and thus an advantage that the stability of signal transmission characteristics in the coupler is enhanced is added.

<Second Embodiment> FIG. 3 is a front sectional view showing the structure of a stripline coupler according to the second embodiment. FIG.
As shown in FIG. 3, in this coupler, the via hole 6 penetrating between the lower surface of the substrate 1 and the bottom surface of the groove is formed in the substrate 1. The inner wall of the via hole 6 is covered with a conductor foil, and the shield conductor 4 and the ground conductor 2 are electrically short-circuited through this conductor foil. Therefore, the shield conductor 4 is
In addition to the function of confining the electromagnetic wave radiated from the strip line 3, it also has a function of suppressing the invasion of the electromagnetic wave from the outside to the strip line 3, which brings about an advantage that the stability of the signal transmission characteristic in the coupler is enhanced. .

By forming via holes 6 in the substrate 1 in advance before embedding the shield conductor 4 and the dielectric layer 5 in the groove formed in the substrate 1, the shield conductor 4 and the shield conductor 4 are formed at the same time. A short circuit with the ground conductor 2 is realized. That is, in the coupler of this embodiment, an electrical short circuit between the shield conductor 4 and the ground conductor 2 can be realized by a simple process as compared with the configuration using the jumper wire.

<Third Embodiment> FIG. 4 is a front sectional view showing the structure of a stripline coupler according to the third embodiment. FIG.
As shown in FIG. 3, in this coupler, the widths of the two strip lines 3 and 3'arranged in parallel with the upper surface of the dielectric layer 5 are different from each other. In the strip lines 3 and 3 ', the characteristic impedance of each line can be changed individually by changing the line width of each of them. Therefore, by appropriately setting the line widths of the strip lines 3 and 3'individually, it is possible to meet the requirements for each line regarding the characteristic impedance.

<Fourth Embodiment> FIG. 5 is a front sectional view showing the structure of a strip line coupler according to a fourth embodiment. Figure 5
As shown in FIG. 2, in this coupler, two (generally a plurality of) strip-shaped grooves of the same size are formed, the shield conductor 4 is formed in each of the grooves, and further, the dielectric layers 5 and 5 '.
Are embedded respectively. Here, the dielectric constants of the two dielectric layers 5 and 5'are different from each other. Each dielectric layer 5,
Two strip-shaped strip lines 3 of the same size are arranged on the upper surface of 5 '.

As described above, in this coupler, two unit couplers having different dielectric constants of the embedded dielectric layers 5 and 5 ', but having the same shape in all, are arranged side by side on the same substrate. Has been done. Since the dielectric layers 5 and 5 ′ have different permittivities, the coupling degrees of the two unit couplers are different from each other. Also,
Since all shapes are the same, it is easy to manufacture. For example, an efficient manufacturing method is to form all the strip lines 3 at the same time by etching, but at this time, the line widths of the strip lines 3 are the same from the viewpoint of facilitating the control of the etching depth. Is desirable. That is, the coupler of this embodiment has an advantage that a plurality of unit couplers having different degrees of coupling can be easily formed on a single substrate.

Further, this coupler has a plurality of unit couplers on a single substrate 1 and functions as a kind of integrated circuit. Therefore, by using this coupler, a circuit having a plurality of couplers can be easily configured and the degree of integration can be increased.

<Fifth Embodiment> FIG. 6 is a front sectional view showing the structure of a strip line coupler according to a fifth embodiment. Figure 6
As shown in FIG. 3, in this coupler, another shield conductor 8 is provided so as to cover the strip line 3 from above. The edge of the shield conductor 8 is connected to the edge of the shield conductor 4. That is, the strip line 3 has two shield conductors 4, 8 in the radial direction.
It is completely surrounded by. Therefore, the effect of confining the electromagnetic wave energy is further enhanced, so that the degree of coupling between the pair of strip lines 3 is further improved. Moreover,
A confinement effect that is equal to or larger than the sum of the confinement effects of electromagnetic waves when either the shield conductor 4 or the shield conductor 8 is provided alone is obtained.

As shown in FIG. 6, in this coupler, the inner cavity of the shield conductor 8 is further filled with the dielectric layer 7. Like the dielectric layer 5, the dielectric layer 7 is made of a material having a higher dielectric constant than the substrate 1. That is, the strip line 3 has a higher dielectric constant than the substrate 1.
It is as if it were buried in the two dielectric layers 5 and 7. As a result, the degree of coupling between the pair of strip lines 3 is further increased.

The dielectric layer 7 may be made of the same material as the dielectric layer 5 or may be made of a different material.

<Sixth Embodiment> FIG. 7 is a front sectional view showing the structure of a stripline coupler according to the sixth embodiment. Figure 7
In this coupler, the inner cavity of the shield conductor 8 is not filled with the dielectric layer 7 as shown in FIG. Alternatively, the dielectric layer 7 is filled with air. Therefore, the effect of confining the electromagnetic wave energy by the shield conductor 8 enhances the coupling degree of the strip line 3 and relaxes or eliminates the stress generated between the strip line 3 and the dielectric layer. There is the advantage that the reliability of the combiner is high.

<Seventh Embodiment> FIG. 8 is a front sectional view showing a structure of a stripline coupler according to a seventh embodiment. FIG.
As shown in FIG. 3, in this coupler, a plate-shaped metal layer 9 functioning as a ground conductor is provided on the upper surface of the substrate 1. A band-shaped groove is formed on the upper surface of the metal layer 9, and the dielectric layer 5 is embedded in the groove. The pair of strip lines 3 are arranged parallel to each other along the upper surface of the dielectric layer 5.

This coupler is similar to the coupler of the first embodiment in that the ground conductor 2 and the shield conductor 4 are integrated. Therefore, the metal layer 9 provides both advantages of improving the degree of coupling due to the effect of confining electromagnetic energy and stabilizing the signal transmission characteristic due to the effect of shielding electromagnetic noise. Moreover, since the ground conductor 2 and the shield conductor 4 are integrally formed, there is an advantage that the manufacturing is easy.

<Eighth Embodiment> FIG. 9 is a front sectional view showing the structure of a stripline coupler according to the eighth embodiment. Figure 9
As shown in FIG. 5, in this coupler, in the coupler of the first embodiment, the strip line 3 is a buried strip line 1.
The configuration is replaced with 0. Each of the two strip lines 10 is made of a strip-shaped conductor and is embedded in the dielectric layer 5 in parallel with each other. Moreover,
These strip lines 10 are arranged so that their main surfaces face each other.

In this coupler, since the strip line 10 is embedded in the dielectric layer 5, the surface area of the strip line 10 covered by the dielectric layer 5 is large. As a result, there is an advantage that the degree of coupling between the strip lines 10 is higher than that of the strip lines 3 arranged on the surface of the dielectric layer 5.

Moreover, since the strip line 10 is strip-shaped and is embedded so that its main surfaces face each other, the area of the facing faces is large. This also brings about a further improvement in the degree of bonding.

FIG. 9 shows an example in which only the upper surface of the strip line 10 is exposed to the outside of the dielectric layer 5.
By doing so, there is an advantage that the connection between the strip line 10 and the external wiring is easy. However, the strip line 10 may be embedded in the dielectric layer 5 to the extent that the upper surface is not exposed. At this time, the degree of coupling between the strip lines 10 is further increased.

Although the strip line 3 is embedded in the dielectric layer 5 embedded in the groove of the substrate 1 in this embodiment, the substrate 1 is not provided with the groove and the dielectric layer 5. By embedding the stripline 3 in the, the degree of coupling is correspondingly improved.

<Ninth Embodiment> It is possible to construct a coupler having a plurality of features at the same time from the features of the respective couplers of the above first to eighth embodiments. The ninth to seventeenth examples below will exemplify such a coupler.

FIG. 10 is a front sectional view showing the structure of the stripline coupler of the ninth embodiment. This coupler has the features of the second embodiment and the features of the fifth embodiment. That is, as shown in FIG. 10, in this coupler, the via hole 6 penetrating between the lower surface of the substrate 1 and the bottom surface of the groove is provided in the coupler of the fifth embodiment (FIG. 6). are doing. This allows the stripline 3
A high degree of coupling between them and an improvement in stability of signal transmission characteristics are realized at the same time.

Moreover, when either the shield conductor 4 or the shield conductor 8 is provided independently and each is electrically connected to the ground conductor 2, a stabilization effect more than the sum of the stabilization effects of the transmission characteristics is obtained. To be

<Tenth Embodiment> FIG. 11 is a front sectional view showing the structure of a stripline coupler according to the tenth embodiment. This coupler has the features of the fourth embodiment and the features of the seventh embodiment. That is, the metal layer 9 that functions as a ground conductor is provided on the upper surface of the substrate 1, and two (generally a plurality) band-shaped grooves of the same size are formed on the upper surface of the metal layer 9. The dielectric layers 5 and 5'having different dielectric constants are embedded in these grooves, respectively. Two strip-shaped strip lines 3 of the same size are arranged on the upper surface of each of the dielectric layers 5 and 5 '.

For this reason, in this coupler, the metal layer 9 simultaneously functions as both the ground conductor and the shield conductor, so that both the effects of improving the coupling degree and stabilizing the transmission characteristics can be obtained with a simple structure. To be In addition, since two unit couplers having different dielectric constants only in the dielectric layers 5 and 5'are arranged in parallel, a plurality of unit couplers having different coupling degrees can be easily formed on the same substrate. The effect can be obtained at the same time.

<Eleventh Embodiment> FIG. 12 is a front sectional view showing the structure of a stripline coupler according to the eleventh embodiment. This coupler has the features of the second embodiment and the features of the eighth embodiment. That is, the strip line 10 is embedded in the dielectric layer 5, and the shield conductor 4 and the ground conductor 2 are short-circuited through the via hole 6 formed in the substrate 1. Therefore, stripline 1
A strong coupling is realized between 0s, and stable signal transfer characteristics are obtained.

<Twelfth Embodiment> FIG. 13 is a front sectional view showing the structure of a stripline coupler according to the twelfth embodiment. This coupler has the features of the third embodiment and the features of the eighth embodiment. In this coupler, strip lines 10 and 10 ′ having different line widths are embedded in the dielectric layer 5. The line widths of the strip lines 10 and 10 'are individually set according to the characteristic impedance required for each line. Therefore, the strip lines 10, 1
A strong coupling is realized between 0's, and at the same time, it is possible to meet the requirements for each line regarding the characteristic impedance.

<Thirteenth Embodiment> FIG. 14 is a front sectional view showing the structure of a stripline coupler according to the thirteenth embodiment. This coupler has the features of the fourth embodiment and the features of the eighth embodiment. That is, as if in the coupler (FIG. 5) of the fourth embodiment, the embedded strip line 10 is provided instead of the strip line 3. Therefore, the strip lines 10, 1
There is an effect that a strong coupling is realized between 0's and at the same time, a plurality of unit couplers having different coupling degrees can be easily configured on the same substrate.

<Fourteenth Embodiment> FIG. 15 is a front sectional view showing a structure of a strip line coupler according to a fourteenth embodiment. This coupler has the features of the fifth embodiment and the features of the eighth embodiment. That is, as if in the coupler of the fifth embodiment (FIG. 6), the embedded strip line 10 is provided instead of the strip line 3. These strip lines 10 are strip-shaped and are embedded in the dielectric layer 5 so that their main surfaces face each other. Therefore, stronger coupling is realized between the strip lines 10 and 10 'than in the couplers of either the fifth embodiment or the eighth embodiment (FIG. 9).

<Fifteenth Embodiment> FIG. 16 is a front sectional view showing the structure of a strip line coupler according to the fifteenth embodiment. This coupler has the features of the sixth embodiment and the features of the eighth embodiment. That is, as if in the coupler (FIG. 7) of the sixth embodiment, the embedded strip line 10 is provided instead of the strip line 3. These strip lines 10 are strip-shaped and are embedded in the dielectric layer 5 so that their main surfaces face each other. Therefore, stronger coupling is realized between the strip lines 10 and 10 'than in the couplers of the sixth embodiment and the eighth embodiment (FIG. 9). Further, since the dielectric layer filling the inside of the shield conductor 8 does not exist, the stress generated inside the coupler is relieved or eliminated, so that there is an advantage that the reliability of the coupler is high.

<Sixteenth Embodiment> FIG. 17 is a front sectional view showing the structure of a strip line coupler according to the sixteenth embodiment. This coupler has the features of the second, fifth, and eighth embodiments. That is, as if in the coupler of the fourteenth embodiment (FIG. 15), the shield conductor 4 and the ground conductor 2 are short-circuited through the via hole 6 formed in the substrate 1. For this reason,
A strong coupling corresponding to the device of the fourteenth embodiment is realized between the strip lines 10 and stable signal transfer characteristics are obtained.

<Seventeenth Embodiment> Features and Seventh of the Fifth Embodiment
A combiner having the features of the embodiments can also be constructed. That is, in the coupler of the seventh embodiment, the shield conductor 8 of the fifth embodiment is attached to the upper surface of the metal layer 9 so as to cover the two strip lines 3, and the inner cavity of the shield conductor 8 is covered with a dielectric material. It is possible to construct a coupler which is filled with layer 7. At this time, the edge portion of the shield conductor 8 is connected to the upper surface of the metal layer 9.

That is, the strip lines 3 are surrounded in the radial direction by the metal layer 9 and the shield conductor 8 without leakage. Therefore, as compared with the coupler of the seventh embodiment, the effect of confining the electromagnetic wave energy is further enhanced, so that the degree of coupling between the pair of strip lines 3 is further improved. In addition, since the inner cavity of the shield conductor 8 is filled with the dielectric layer 7, this also leads to a further improvement in the degree of coupling.

<Modifications> (1) The ninth to seventeenth embodiments are merely some examples of couplers having the respective features of the couplers of the first to eighth embodiments. Absent. For example, it is generally possible to implement the features of the respective embodiments in any combination, such as a coupler having the features of the eighth embodiment and the features of the seventh embodiment.

(2) In the couplers of the respective examples except the seventh, tenth, and seventeenth examples, the shield conductor 4 and the dielectric layer 5 (and 5 ') were provided at the same time. However, the dielectric layer 5 (and 5 ′) may be embedded without forming the shield conductor 4 in the groove provided in the substrate 1. Even with this structure, a high degree of coupling can be obtained due to the dielectric layer 5 (and 5 ′) having a higher dielectric constant than the substrate 1.

(3) Also, the seventh, tenth, and first
In the couplers of the respective embodiments except the seventh embodiment, the shield conductor 4 is formed in the groove provided in the substrate 1 and the dielectric layer 5 (and 5 ′) having a higher dielectric constant than that of the substrate 1 is not provided. Alternatively, a simple dielectric or the same material as the substrate 1 may be embedded inside the shield conductor 4. Even in this configuration, the effect of confining the electromagnetic energy by the shield conductor 4 functions, so that the degree of coupling can be improved correspondingly.

(4) In each of the above embodiments, two strip lines are formed for one unit coupler, so that coupling between two signals is realized. However, in general, three or more strip lines may be configured to couple three or more signals to each other.
The front sectional view of FIG. 18 shows an example of a coupler including three strip lines 3.

Further, even a combiner for realizing the coupling between two signals may be configured to allocate a plurality of strip lines to each signal. Even in such a coupler, three or more strip lines are formed for one unit coupler. That is, in the present invention, the number of strip lines provided in one unit coupler is not limited to two, and may be plural in general.

[0092]

In the stripline type coupler of the first invention, since the stripline is arranged in the dielectric layer having a higher dielectric constant than the substrate, the stripline coupler is satisfied while the restrictions on the material of the substrate are satisfied. A desired high degree of coupling between lines can be obtained. In particular, there is an effect that a high degree of coupling can be obtained even when the material of the substrate is limited to the semiconductor, such as when this coupler constitutes an MMIC. further,
The strip line can have a simple structure by using a dielectric material having a sufficiently high dielectric constant for the dielectric layer. Therefore, in this coupler, it is possible to obtain a desired high degree of coupling without increasing the resistance component while maintaining the simple configuration and the ease of manufacturing which the stripline type coupler originally has. is there.

In the strip line type coupler of the second invention, the strip line is arranged on the upper surface of the dielectric layer, so that the strip line can be easily arranged.

In the strip line type coupler of the third invention, since the strip line is embedded in the dielectric layer,
A higher degree of binding is obtained.

In the strip line type coupler of the fourth aspect of the invention, each of the plurality of strip lines is strip-shaped and is embedded in the dielectric layer such that its principal surfaces face each other. A higher degree of binding is obtained.

In the strip line type coupler of the fifth invention, the sheet-like shield conductor is formed on the substrate so as to cover the inner wall of the groove, and the dielectric layer is embedded in the groove via the shield conductor. Therefore, the electromagnetic waves emitted from the strip line are confined inside the shield conductor. For this reason, the electromagnetic wave energy that is originally lost by radiation also contributes to the coupling, so that the coupling between the strip lines is further strengthened.

Further, both the shield conductor and the dielectric layer are provided by utilizing the groove formed in the substrate. That is, in this coupler including both the shield conductor and the dielectric layer, the groove is effectively used to increase the degree of coupling.

In the stripline type coupler of the sixth invention, since the shield conductor and the ground conductor are electrically connected, the shield conductor also has a function of suppressing the intrusion of electromagnetic waves from the outside into the stripline. Therefore, the stability of the signal transmission characteristic of the coupler is enhanced.

In the stripline type coupler of the seventh invention, the shield foil and the ground conductor are electrically connected by the conductor foil formed on the inner wall of the through hole penetrating the bottom surface of the groove and the bottom surface of the substrate. Therefore, an electrical short circuit between the shield conductor and the ground conductor is realized by a simple process.

In the stripline type coupler of the eighth invention, the metal layer is present in at least the upper layer portion of the substrate, and the groove for burying the dielectric layer is formed on the upper surface of the metal layer. Since this metal layer can also function as a ground conductor, both effects of improved coupling and stabilization of signal transmission characteristics are brought about by a single metal layer. That is, both effects can be obtained simultaneously with a simple structure that is easy to manufacture.

In the stripline type coupler of the ninth invention, since the shield conductor covering the plurality of striplines is provided on the substrate, the electromagnetic wave energy that would otherwise be lost by radiation also contributes to the coupling. As a result, the coupling between the strip lines is further strengthened.

In the stripline type coupler of the tenth aspect of the invention, the first and second shield conductors cover the entire circumference of the stripline, so that the effect of confining electromagnetic waves is further enhanced. Moreover, an effect more than the sum of the confinement effects when only one of the first and second shield conductors is provided is provided.

In the strip line type coupler of the eleventh invention, the first and second shield conductors cover the entire circumference of the strip line, and the shield conductors and the ground conductors are electrically connected. Therefore, the intrusion of electromagnetic waves from the outside into the strip line can be suppressed more effectively.
As a result, the stability of signal transmission characteristics is further enhanced. Moreover, the first and the second connected to the ground conductor
The effect is equal to or more than the sum of the stabilizing effects when only one of the shield conductors is provided.

In the stripline type coupler of the twelfth aspect of the invention, since the entire circumference of the stripline is covered by the metal layer and the shield conductor, the effect of confining electromagnetic waves is further enhanced. Furthermore, since the metal layer and the shield conductor are connected to each other, the effect of suppressing the intrusion of electromagnetic waves from the outside into the strip line is further enhanced.

In the strip line type coupler of the thirteenth invention, since the inner cavity of the shield conductor is filled with a dielectric material having a higher dielectric constant than the substrate, a higher coupling degree can be obtained.

In the strip line type coupler of the fourteenth invention, since the inner cavity of the second shield conductor is filled with the dielectric material having a higher dielectric constant than that of the substrate, a higher coupling degree can be obtained.

In the strip line type coupler of the fifteenth invention, since the dielectric layer has a high dielectric material, a higher degree of coupling can be obtained. In addition, since the dielectric layer having the high dielectric material is embedded in the groove provided in the substrate, the mechanical strength of the coupler is not impaired even when the brittle high dielectric material is used.

In the strip line type coupler of the sixteenth invention, the widths of the plurality of strip lines are individually adjusted so as to realize the required characteristic impedance. We can also meet your requirements.

In the strip line type coupler of the seventeenth invention, a plurality of grooves are formed in the substrate, and a plurality of unit couplers are provided corresponding to each groove. That is,
A plurality of unit couplers are formed on a single substrate. Therefore, by using this coupler, a circuit having a plurality of couplers can be easily constructed, and the degree of integration can be increased.

In the strip line type coupler of the eighteenth invention, the plurality of unit couplers have the same shape, and the material of the dielectric layer is individually selected based on the requirement of the degree of coupling. There is. Therefore, it is possible to easily manufacture a coupler that meets the requirements regarding the degree of coupling that differs for each unit coupler.

In the strip line type coupler of the nineteenth invention, a sheet-shaped shield conductor is formed so as to cover the inner wall of the groove formed on the upper surface of the substrate. Therefore, the effect of confining the electromagnetic energy by the shield conductor functions to improve the coupling degree.

In the strip line type coupler of the twentieth invention, since a plurality of strip lines are embedded in the substrate, a high degree of coupling between these strip lines can be obtained.

[Brief description of drawings]

FIG. 1 is a perspective view of a stripline coupler according to a first embodiment.

FIG. 2 is a front cross-sectional view of the stripline coupler of the first embodiment.

FIG. 3 is a front sectional view of a stripline coupler according to a second embodiment.

FIG. 4 is a front sectional view of a stripline coupler according to a third embodiment.

FIG. 5 is a front sectional view of a stripline coupler according to a fourth embodiment.

FIG. 6 is a front sectional view of a stripline coupler according to a fifth embodiment.

FIG. 7 is a front sectional view of a stripline coupler according to a sixth embodiment.

FIG. 8 is a front sectional view of a stripline coupler according to a seventh embodiment.

FIG. 9 is a front sectional view of a stripline coupler according to an eighth embodiment.

FIG. 10 is a front sectional view of a stripline coupler according to a ninth embodiment.

FIG. 11 is a front sectional view of a stripline coupler according to a tenth embodiment.

FIG. 12 is a front sectional view of a stripline coupler according to an eleventh embodiment.

FIG. 13 is a front cross-sectional view of a stripline type coupler according to a twelfth embodiment.

FIG. 14 is a front sectional view of a stripline type coupler according to a thirteenth embodiment.

FIG. 15 is a front sectional view of a stripline coupler of the 14th embodiment.

FIG. 16 is a front sectional view of a stripline coupler of the 15th embodiment.

FIG. 17 is a front sectional view of a stripline coupler of the 16th embodiment.

FIG. 18 is a front cross-sectional view of a modified stripline coupler.

FIG. 19 is a front sectional view of a conventional stripline coupler.

FIG. 20 is a front sectional view of a conventional stripline coupler.

[Explanation of symbols]

1 substrate, 2 ground conductor, 3 strip line, 4 shield conductor, 5 dielectric layer, 6 via hole, 7 dielectric layer, 8 shield conductor, 9 metal layer, 10 strip line.

Claims (20)

[Claims] 1. A strip line type coupler for coupling an electromagnetic signal, wherein a groove is formed in an upper surface of a substrate, and a dielectric layer having a higher dielectric constant than that of the substrate is embedded in the groove, A stripline-type coupler characterized in that a plurality of striplines are arranged on the body layer. 2. The strip line type coupler according to claim 1, wherein the plurality of strip lines are arranged on an upper surface of the dielectric layer. 3. The strip line type coupler according to claim 1, wherein the plurality of strip lines are embedded in the dielectric layer. 4. The strip line, wherein each one of the strip lines has a strip-like shape and is embedded in the dielectric layer so that main surfaces thereof face each other. Stripline coupler. 5. The sheet-shaped shield conductor is formed on the substrate so as to cover the inner wall of the groove, and the dielectric layer is embedded in the groove via the shield conductor. The stripline coupler according to claim 1. 6. The strip line according to claim 5, wherein a sheet-shaped ground conductor is provided on the lower surface of the substrate, and the ground conductor and the shield conductor are electrically connected. Type coupler. 7. A through hole penetrating a bottom surface of the groove and a lower surface of the substrate is formed in the substrate, and the shield conductor and the ground conductor are formed by a conductor foil formed on an inner wall of the through hole. 7. The stripline coupler according to claim 6, wherein is electrically connected. 8. The stripline coupler according to claim 1, wherein the substrate has a metal layer on at least an upper layer portion thereof, and the groove is formed on an upper surface of the metal layer. 9. The stripline-type coupler according to claim 1, wherein a shield conductor covering the plurality of striplines is provided on the substrate. 10. The shield conductor is a first shield conductor, and a second shield conductor covering the plurality of strip lines is provided on the substrate, and further, the first shield conductor is provided.
The stripline type coupler according to claim 5, wherein both ends of the second shield conductor and the second shield conductor jointly cover the entire circumference of the plurality of striplines by connecting their ends. . 11. The shield conductor is a first shield conductor, and a second shield conductor for covering the plurality of strip lines is provided on the substrate, and further, the first shield conductor is provided.
7. The stripline type coupler according to claim 6, wherein both ends of the second shield conductor and the second shield conductor jointly cover the entire circumference of the plurality of striplines by connecting their ends. . 12. A shield conductor that covers the plurality of strip lines is provided on the substrate, and the shield conductor and the metal layer are connected by connecting an end portion of the shield conductor to the metal layer. 9. The strip line type coupler according to claim 8, wherein both of the strip line couplers cover the entire circumference of the plurality of strip lines together. 13. The stripline coupler according to claim 9, wherein the inner cavity of the shield conductor is filled with a dielectric having a higher dielectric constant than that of the substrate. 14. The strip line type coupling according to claim 10, wherein the inner cavity of the second shield conductor is filled with a dielectric having a higher dielectric constant than that of the substrate. vessel. 15. The stripline coupler according to claim 1, wherein the dielectric layer comprises a high dielectric material. 16. The stripline-type coupler according to claim 1, wherein each width of the plurality of striplines is individually adjusted so as to realize a required characteristic impedance. 17. A stripline coupler for coupling an electromagnetic signal, wherein a plurality of grooves are formed on an upper surface of a substrate, and a dielectric layer having a higher dielectric constant than that of the substrate is embedded in the plurality of grooves. A plurality of unit couplers, each of which functions as a single coupler, are formed by disposing a plurality of strip lines for each of the dielectric layers. The stripline coupler according to 1. 18. The shape of the groove and the shape of the strip line are common to the plurality of unit couplers, and the dielectric layer is formed according to the degree of coupling required for each unit coupler. 2. The method according to claim 1, wherein the material having the required permittivity is individually selected.
7. The stripline coupler according to item 7. 19. A strip line type coupler for coupling an electromagnetic signal, wherein a groove is formed on an upper surface of a substrate, and a sheet-shaped shield conductor is formed on the substrate so as to cover an inner wall of the groove. In addition, a strip line type coupler characterized in that a dielectric layer is embedded in the groove via the shield conductor, and a plurality of strip lines are arranged in the dielectric layer. 20. A stripline coupler for coupling an electromagnetic signal, wherein a plurality of striplines are embedded in a substrate.