JP3399771B2 - Microwave circuit - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microwave circuit used in an ultrahigh frequency band such as microwave and millimeter wave.

[0002]

2. Description of the Related Art FIG. 7 shows an IE transactions on microwave theory and.
Techniques, Volume 32, No. 5, May 1984, pp. 544-547 (IEEE TRANS
ACTIONS ON MICROWAVE THEO
RY AND TECHNIQUES, VOL. MTT
-32, NO. 5, MAY 1984, pp. 544-
FIG. 5 is a cross-sectional configuration diagram showing an example of a conventional microwave circuit in which a conductor is provided on a dielectric substrate on which the microstrip line shown in FIG. 547) is formed. In FIG. 7, 5
Is a dielectric substrate, 23 is a microstrip line, 6 is a ground conductor formed on the back surface of the dielectric substrate 5, and 24 is a conductor. FIG. 8 shows a change in the frequency characteristic depending on the presence or absence of the conductor 24 shown in FIG. 7 in which the bandpass filter constituted by the microstrip line 23 is formed on the dielectric substrate 5. Figure 8
As shown in FIG. 3, when the conductor 24 is provided on the microstrip line 23 that constitutes the bandpass filter, the pass band is about one half of that when the conductor 24 is not provided.
You can see that it is. This is because the characteristics of the microstrip line 23 forming the bandpass filter change depending on the presence or absence of the conductor 24.

Conventionally, the microstrip line 23 operates by an electromagnetic field generated between the conductor of the microstrip line 23 and the ground conductor 6 formed on the back surface of the dielectric substrate 5. In this case, the electromagnetic field is confined in the dielectric between the conductor 24 of the microstrip line 23 and the ground conductor 6 formed on the back surface of the dielectric substrate 5, and the dielectric substrate through the space above the microstrip line 23. 5 and the ground conductor 6 formed on the back surface of the conductor 5 both exist.

[0004]

Since the conventional microwave circuit is constructed as described above, the electromagnetic field generated in the operation of the microstrip line 23 is formed on the back surface of the dielectric substrate 5 through a space. The electromagnetic field generated between the ground conductor 6 and the ground conductor 6 occupies a large space. Since the microstrip line 23 is mounted on the metal package, when the lid of the metal package having the same potential as the ground conductor 6 formed on the back surface of the dielectric substrate 5 is brought close to the microstrip line 23, the lid of the metal package and the micro An electromagnetic field is also generated between the strip lines 23, the microwave propagation mode changes, and the phenomenon that the operation of the microstrip lines 23 ceases occurs. Therefore, in order to operate as the microstrip line 23, there is a problem that the distance between the lid of the metal package and the microstrip line 23 must be a distance that does not affect the operation of the microstrip line 23.

The present invention has been made to solve the above problems, and an object of the present invention is to obtain a microwave circuit which can be made thin and compact without changing the microwave transmission characteristics. To do.

[0006]

[0007]

According to a first aspect of the present invention, there is provided a microwave circuit including a back side ground conductor formed on a back side.
Having a dielectric substrate and a lead formed on the dielectric substrate
Formed with a certain gap between the body and the main conductor
A coplanar line consisting of a ground conductor and the coplanar line
To cover the end face of the dielectric substrate along the longitudinal direction of the path
Is provided in the ground plane and constitutes the coplanar line.
Between the body and the backside ground conductor of the dielectric substrate.
And a dielectric covering the coplanar line.
Body film, conductor formed on the dielectric film, and the back surface
Includes a ground conductor as a component and encloses the coplanar line
And a shield component configured in a
Film as has Tsu covering a coplanar line path in a layer by a first dielectric and a second dielectric, is formed on the second dielectric surface of the uppermost dielectric covering the coplanar lines path to the layered, dielectric The conductor film electrically connected to the backside ground conductor of the body substrate is included as a constituent part of the shield constituent part.

A microwave circuit according to a second aspect of the present invention is electrically connected to a backside ground conductor formed on the backside of a dielectric substrate, and the dielectric is formed on a plate-shaped conductor having a larger area than the dielectric substrate. The body substrate is configured.

In a microwave circuit according to a third aspect of the present invention, a metal thin film formed so as to cover the end face of the dielectric substrate along the longitudinal direction of the coplanar line is used as a connection conductor, and the conductor film is the metal. Formed by connecting with a thin film,
The shield component is configured to enclose the coplanar line with the conductor film, the metal thin film, and the backside ground conductor of the dielectric substrate.

In a microwave circuit according to a fourth aspect of the present invention, the metal thin film formed so as to cover the end face of the dielectric substrate along the longitudinal direction of the coplanar line is used as a connection conductor, and the conductor film is the metal. Formed by connecting with a thin film,
The shield component is configured to enclose the coplanar line with the conductor film, the metal thin film, the backside ground conductor, and the plate conductor.

According to a fifth aspect of the present invention, there is provided a microwave circuit in which a backside ground conductor of the dielectric substrate is formed so as to cover the end face of the dielectric substrate along the longitudinal direction of the coplanar line. Is used as a connection conductor, and a conductor film is formed by being connected to the backside ground conductor formed by extending even over the end surface of the dielectric substrate, and the shield forming portion extends over the conductor film and the end surface. The backside ground conductor of the dielectric substrate thus formed surrounds the coplanar line.

In a microwave circuit according to a sixth aspect of the present invention, the coplanar line is provided with a lumped constant element formed close to a ground conductor forming the coplanar line.

According to a seventh aspect of the present invention, there is provided a microwave circuit including a photoelectric conversion element for converting an electric signal supplied via a coplanar line into an optical signal.

A microwave circuit according to an eighth aspect of the present invention includes a photoelectric conversion element that converts an optical signal into an electric signal and supplies the electric signal to a coplanar line.

A microwave circuit according to a ninth aspect of the present invention is provided with an optical signal input / output section for inputting / outputting an optical signal to / from a photoelectric conversion element.

A microwave circuit according to a tenth aspect of the present invention is a microwave circuit in which a second dielectric forming a dielectric film covers a coplanar line, a photoelectric conversion element and an optical signal input / output section on a plate-shaped conductor. It is made of material.

In a microwave circuit according to an eleventh aspect of the present invention, a photoelectric conversion element is provided on a conductor formed on the surface of a silicon substrate arranged on a plate-shaped conductor, and the photoelectric conversion element is formed on the surface of the silicon substrate. And an optical fiber for inputting and outputting an optical signal to and from the photoelectric conversion element is provided as an optical signal input / output unit.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described below. Embodiment 1. 1 is a sectional configuration diagram showing a configuration of a microwave circuit according to a first embodiment of the present invention. In the figure, 1 is a main line (main conductor) that constitutes the coplanar line 7, 2 is a ground conductor that constitutes the coplanar line 7, and 3 is a slot formed between the main line 1 and the ground conductor 2. 5 is a dielectric substrate having a main line 1, a ground conductor 2 and a slot 3 formed on the surface, 4 is a main line 1 formed on the surface of a dielectric substrate 5,
A first dielectric (dielectric film) covering the ground conductor 2 and the slot 3, 6 is a backside ground conductor (connection conductor) formed on the backside of the dielectric substrate 5, and 11 is formed on the end face of the dielectric substrate 5. A thin metal film (connecting conductor) connecting the ground conductor 2 forming the coplanar line 7 and the backside grounding conductor 6 formed on the backside of the dielectric substrate 5, and the second dielectric (9) covering the first dielectric 4 (connection conductor). (Dielectric film), 8 is a conductor film that covers the surface of the second dielectric 9, and 10 is a substrate composed of the coplanar line 7, the dielectric substrate 5, and the backside ground conductor 6 formed on the backside of the dielectric substrate 5. It is a mounted plate-shaped ground conductor (plate-shaped conductor). The second dielectric 9 can be made of a transparent material.

The microwave circuit according to the first embodiment is provided with these respective components, and a coplanar line 7 composed of the main line 1, the ground conductor 2 and the slot 3 is formed on the surface of the dielectric substrate 5, and the coplanar line is formed. The ground conductor 2 forming the line 7 and the backside ground conductor 6 on the backside of the dielectric substrate 5 are connected by a metal thin film 11 at the end face of the dielectric substrate 5, and the coplanar line 7, the dielectric substrate 5 and the backside grounding conductor 6 are connected. A substrate constituted by is mounted on the plate-shaped ground conductor 10. The coplanar line 7 is covered with the first dielectric 4 and the second dielectric 9, and the second dielectric 9 is covered with the conductor film 8 and connected to the metal thin film 11.

In FIG. 2, the main line 1 has a width of 30 μm, and the slot 3 formed between the ground conductor 2 and the main line 1 has a width of 6 μm.
The 0 μm coplanar line 7 and the dielectric substrate 5 have a thickness of 10
0 μm, the dielectric constant of the dielectric substrate is 12.9, the dielectric constant on the coplanar line 7 is one, and the dielectric constant is 2.6.
It shows an example of calculation results of characteristics (characteristic impedance of the coplanar line 7) when the distance between the coplanar line 7 and the conductor film 8 is changed. In order to simplify the calculation, the side surface of the conductor film 8 is perpendicular to the end surface of the dielectric substrate 5,
The upper surface of the conductor film 8 has a structure provided in parallel with the dielectric substrate 5. From FIG. 2, the distance between the coplanar line 7 and the conductor film 8 is 1
The characteristic impedance hardly changes even when it is brought close to 00 μm.

As described above, in the microwave circuit according to the first embodiment, since the coplanar line 7 is used as the transmission line, the main line formed on the surface of the dielectric substrate 5 forming the coplanar line 7 in its operation. An electromagnetic field is generated between 1 and the ground conductor 2. Electromagnetic fields generated in this case include those passing through the dielectric forming the coplanar line 7 and those passing through the dielectric covering the coplanar line 7, both of which are via the dielectric and the coplanar line 7. Since the distance between the main line 1 on the surface of the dielectric substrate 5 and the ground conductor 2 on the surface of the dielectric substrate 5 can be narrowed in relation to the line width of the main line 1, the conventional microstrip line 23 is used. The coplanar line 7 of this embodiment can occlude the electromagnetic field by reducing the electromagnetic field radiated into the space, as compared with the above case. For this reason, the distance between the coplanar line 7 which is a microwave transmission line and the conductor formed above the transmission line can be made smaller than before, so that the conductor film 8 can be brought closer to the coplanar line 7. There is an effect that a thin and small microwave circuit can be obtained.

The ground conductor 2 forming the coplanar line 7 and the backside ground conductor 6 formed on the backside of the dielectric substrate 5 are connected by a metal thin film 11 at the end face of the dielectric substrate 5, and the coplanar line 7 is formed at the same end face. Since the conductor film 8 covering the upper first dielectric 4 is also connected to the metal thin film 11 to serve as a ground conductor, the conductor film 8 acts as a shield and shields an electromagnetic field radiated into the space to prevent a micro-radiation to the space. There is an effect that a microwave circuit with less loss due to wave radiation can be obtained.

[0023]Reference example 1. Although the embodiments of the present invention are not shown, understanding
Here is a reference example to help you. Figure 3Is reference example 1By
It is a cross-sectional block diagram which shows the structure of a microwave circuit. In Figure 3
For the same or corresponding parts as in FIG.
The description is omitted. In the figure, 12 is a coplanar line
The back surface of the ground conductor 2 and the back surface of the dielectric substrate 5 that form the path 7.
A gold wire which is connected to the ground conductor 6 at the end surface of the dielectric substrate 5.Ya
sois there.

In the microwave circuit of Reference Example 1 , the ground conductor 2 forming the coplanar line 7 and the backside ground conductor 6 on the backside of the dielectric substrate 5 are gold wires 1 on the end face of the dielectric substrate 5.
They are connected by means of two, and as a result, the same effect as the microwave circuit of the first embodiment can be obtained.

[0025]Reference example 2. Figure 4Reference example 2Section showing the structure of the microwave circuit
It is a block diagram. 4 is the same as or equivalent to FIG.
Minutes are given the same reference numerals, and description thereof will be omitted. Figure smell
13 is the ground conductor 2 that constitutes the coplanar line 7 and
Connect the backside ground conductor 6 on the backside of the electric substrate 5 to the dielectric
Through-hole formed on the body substrate 5In Leis there.

In the microwave circuit of the second reference example , the ground conductor 2 forming the coplanar line 7 and the back surface ground conductor 6 on the back surface of the dielectric substrate 5 are connected by the through hole 13 formed in the dielectric substrate 5. As a result, the same effect as the microwave circuit according to the first embodiment can be obtained.

[0027]Embodiment 2. FIG. 5 shows the invention.Embodiment 2By microwave circuit
3 is a cross-sectional configuration diagram showing the configuration of FIG. 5 is the same as FIG.
The same symbols are attached to one or the corresponding parts and explanations are omitted.
I will omit it. In the figure, 14 is formed on the surface of the dielectric substrate 5.
A plurality of conductors arranged in parallel, 15 is a conductor 1
4 is an air bridge that connects 4 and the ground conductor 2. this
A plurality of conductors 14 arranged in parallel and an air bridge
Spiral inductor (lumped element) 1 by J
6 are configured. The ground conductor 2 is a spiral inductor.
It is formed in the vicinity of the periphery of the kector 16. Also thisFruit
Form 2The backside ground conductor 6 of the dielectric substrate 5 of
Form 1, In Reference Examples 1 and 2Is formed only on the back surface of the dielectric substrate 5.
Although it was formed, the back surface and end surface of the dielectric substrate 5
Ground conductor that forms the coplanar line 7.
It is connected to the body 2.

In the microwave circuit according to the second embodiment ,
Since the ground conductor is formed in the vicinity of the periphery of the element together with the lumped element, an electromagnetic field is generated between the conductor or electrode forming the lumped element and the ground conductor 2 on the surface of the dielectric substrate 5 in the operation. The electromagnetic field generated in this case is either through a dielectric that forms the lumped constant element or through a dielectric that covers the lumped constant element, both of which pass through the dielectric and form the lumped constant element. By placing the conductor or electrode and the ground conductor 2 on the surface of the dielectric substrate 5 close to each other, the electromagnetic field spreading in the space can be confined in the vicinity of the lumped constant element as compared with the case of the conventional lumped element. As a result, the distance between the coplanar line 7, which is a microwave transmission line, and the conductor formed above the transmission line can be made closer than before.

[0029]Embodiment 3. FIG. 6 shows the invention.Embodiment 3By microwave circuit
3 is a cross-sectional configuration diagram showing the configuration of FIG. thisEmbodiment 3The Ma
The microwave circuit is the same as in the first embodiment.And Reference Examples 1 and 2, actual
Form 2For each microwave circuit described in
The microwave signal supplied via the Lena line 7 is transmitted as an optical signal.
Diode that converts the signal to optical fiber and outputs to optical fiber
The photoelectric conversion element is additionally provided. In addition, this
The photoelectric conversion element of the
With the function of converting into a signal and supplying it to the coplanar line 7.
May be a child.

In FIG. 6, reference numerals 1, 4, 5 and 6 denote those in FIG.
This is the same as the portion of the microwave circuit described with reference to FIGS. 3, 4, and 5 with the same reference numeral, and the same reference numeral is given to them and the description thereof is omitted. In the figure, 10 is a plate-shaped ground conductor, a microwave circuit according to the fifth embodiment, the first embodiment in order to secure a space for additionally provided a photoelectric conversion element such as a laser diode, reference
It has a larger area than the plate-shaped ground conductors of Examples 1 and 2 and Embodiment 2 . The second dielectric 9 includes the coplanar line 7, the photoelectric conversion element such as the laser diode 18, the optical fiber (optical signal input / output section) 21 and the like, and the plate-shaped ground conductor 1.
It is a dielectric made of a transparent material that is covered on the surface.

A conductor film 8 is formed on the surface of the second dielectric 9, and the conductor film 8 has a coplanar line near the left end when the microwave circuit having the structure of the first embodiment is used. 7 is electrically connected to the ground conductor 2 or the metal thin film 11, and the vicinity of the right end is electrically connected to the plate-shaped ground conductor 10. Although the plan view of the microwave circuit shown in FIG. 6 viewed from above is not shown, the conductor film 8 is not shown.
Is in electrical contact with the ground conductor 2 or the metal thin film 11 of the coplanar line 7 near its left end, and is in electrical contact with the plate-like ground conductor 10 as shown near the right end of the conductor film in FIG. In this state, the photoelectric conversion element such as the laser diode 18 and the optical fiber 21 are covered on the plate-shaped ground conductor 10. As a result, the conductor film 8, the plate-shaped ground conductor 10, and the metal thin film 11 form a shield component that covers the coplanar line 7, and the loss due to radiation to the space when the microwave propagates through the coplanar line 7. It is configured to be suppressed. Further, a gap is formed between the conductor film 8 and the dielectric substrate 5, and is for exposing the main line 1 of the coplanar line 7 to the outside so as not to contact the conductor film 8 from this gap. is there.

In the case of using the microwave circuits having the configurations of the first reference example and the second reference example , the conductor film 8 is exposed to the outside so that the main line 1 of the coplanar line 7 does not contact the conductor film 8. The photoelectric conversion elements such as the laser diode 18 and the optical fiber 21 are plate-shaped in a state of being in electrical contact with the plate-shaped ground conductor 10 as shown in the vicinity of the right end portion of the conductor film in FIG. Ground conductor 1
0 is covered. As a result, the conductor film 8 and the plate-shaped grounding conductor 10 form a shield component that covers the coplanar line 7, and the loss due to radiation to the space when the microwave propagates through the coplanar line 7 is suppressed. Is configured.

When the microwave circuit of the third embodiment is used, the ground conductor 2 of the coplanar line 7 or the backside ground conductor 6 on the end face of the dielectric substrate 5 is located near the left end.
Is electrically connected to the plate-shaped ground conductor 10 near the right end. Although the plan view of the microwave circuit shown in FIG. 6 viewed from above is not shown in this case, the conductor film 8 has a coplanar line 7 near the left end thereof.
Of the grounding conductor 2 or the backside grounding conductor 6 on the end face of the dielectric substrate 5, and also electrically contacts the plate-like grounding conductor 10 as shown in the vicinity of the right end of the conductor film 8 in FIG. In such a state, the photoelectric conversion element such as the laser diode 18 and the optical fiber 21 are covered on the plate-shaped ground conductor 10. As a result, the conductor film 8, the plate-shaped ground conductor 10, and the back-side ground conductor 6 on the end surface of the dielectric substrate 5 form a shield component that covers the coplanar line 7, and the microwave propagates through the coplanar line 7. It is configured so that the loss due to radiation to the space at that time is suppressed.

Reference numeral 20 is a silicon substrate formed on the surface of the plate-like ground conductor, 19 is a conductor formed at the end of the surface of the silicon substrate 20, and 17a is a gold wire connecting the conductor 19 and the plate-like ground conductor 10. Reference numeral 18 is a laser diode mounted on the conductor 19, 17b is a gold wire for supplying the microwave supplied to the main line 1 of the coplanar line 7 to the laser diode 18, and 17c is a laser diode 18
Is a gold wire that connects the ground terminal and the conductor 19. Reference numeral 21 is an optical fiber arranged in the V groove formed on the surface of the silicon substrate 20 so that the laser oscillation surface of the laser diode 18 and the end surface of the laser diode 18 face each other. It is a fiber cable.
In this case, the second dielectric 9 is made of a transparent material and is filled in the first dielectric 4, the laser diode 18, the optical fiber 21, and the optical fiber cable 22 on the coplanar line 7.

The microwave circuit according to the third embodiment includes the above-described components, and the microwave circuit according to the first embodiment , reference example 1,
2. Any of the microwave circuits having the configuration described in the second embodiment is used, and the conductor 19 formed at the end on the silicon substrate 20 and the plate-shaped ground conductor 10 are connected by the gold wire 17a. , Laser diode 18 on conductor 19
Is mounted, and the optical fiber cable 22 and its optical fiber 21 are arranged in a linear V groove formed at a position on the silicon substrate that coincides with the laser oscillation surface of the laser diode 18. Then, the positions of the optical fiber cable 22 and the optical fiber 21 are fixed by the filled second dielectric 9 made of a transparent material, and the end face of the optical fiber 21 is installed close to the laser oscillation surface of the laser diode 18. . As a result, the laser light oscillated by the laser diode 18 by the microwave supplied from the coplanar line 7 is incident from the end face of the optical fiber 21 and is sent to the outside.

As described above, in the third embodiment , the distance between the coplanar line 7 which is a microwave transmission line and the conductor film 8 formed above the transmission line can be made smaller than in the conventional case. An effect that a thin and small microwave circuit in which loss due to radiation of microwaves to the space is reduced and a microwave circuit capable of inputting an optical signal connected to an optical element circuit such as the laser diode 18 can be obtained There is.

[0037]

[0038]

As described above, according to the first aspect of the invention, the dielectric substrate having the back side ground conductor formed on the back side is provided.
A plate, a main conductor formed on the dielectric substrate, and the main
From the conductor and the ground conductor formed with a certain gap
And the coplanar line that becomes the longitudinal direction of the coplanar line
Is provided to cover the end surface of the dielectric substrate along
The grounding conductor and the dielectric material forming the coplanar line
Connection for electrically connecting the backside ground conductor of the board
A conductor, a dielectric film covering the coplanar line, and the dielectric film.
Constituting the conductor formed on the body membrane and the backside ground conductor
Included as a part and configured to enclose the coplanar line
And a first shield as a dielectric film.
Layered on the coplanar line by the electric body and the second dielectric
And covers the coplanar line in a layered manner.
A dielectric layer formed on the second dielectric surface of the top layer of the dielectric
Conductor film electrically connected to the backside ground conductor of the body substrate
Including as a component of the shield component
Then, the electromagnetic field of the microwave propagating through the coplanar line is concentrated in a predetermined gap filled with the first dielectric, and the conductor formed on the dielectric film can be brought close to the coplanar line. Further, since the electromagnetic field radiated into the space is shielded by the shield component,
The effect is that the thickness of the circuit itself can be reduced and the size can be reduced without changing the transmission characteristics.

According to the second aspect of the invention, the dielectric substrate is formed on the plate-shaped conductor which is electrically connected to the backside ground conductor and has a larger area than the dielectric substrate. Therefore, the transmission characteristics are not changed. As a result, the circuit itself can be thinned to be compact, and the mechanical strength against the stress generated in the dielectric substrate can be improved.

According to the third aspect of the invention, a metal thin film formed so as to cover the end face of the dielectric substrate along the longitudinal direction of the coplanar line is used as a connection conductor, and the conductor film is connected to the metal thin film. , The conductor film, the metal thin film, and the back surface grounding conductor are wrapped around the coplanar line by a shield component, so that the electromagnetic field of the microwave propagating through the coplanar line is generated by the metal thin film from the back surface grounding conductor. The conductor formed on the dielectric film can be brought close to the coplanar line by concentrating in a predetermined gap between the ground conductor and the main conductor of the coplanar line electrically connected to the coplanar line. Since the electromagnetic field radiated to is shielded by the shield component,
The effect is that the thickness of the circuit itself can be reduced and the size can be reduced without changing the transmission characteristics.

According to the fourth aspect of the present invention, the metal thin film formed so as to cover the end face of the dielectric substrate along the longitudinal direction of the coplanar line is used as the connection conductor, and the conductor film is connected to the metal thin film. , The conductor film, the metal thin film, the back surface grounding conductor, and the shield constituent part composed of a plate-shaped conductor, so that the coplanar line is wrapped, the electromagnetic field of the microwave propagating through the coplanar line is generated by the metal thin film. The conductor formed on the dielectric film is concentrated in a predetermined gap between the ground conductor and the main conductor of the coplanar line electrically connected to the backside ground conductor and the plate-shaped conductor, and the coplanar line is formed. Since the electromagnetic field radiated into the space is shielded by the shield component, the thickness of the circuit itself can be maintained without changing the transmission characteristics. There is an effect that can be achieved is a thin and compact.

According to the fifth aspect of the present invention, the backside ground conductor of the dielectric substrate is formed so as to cover the end face of the dielectric substrate along the longitudinal direction of the coplanar line so as to be connected to the connection conductor. And the backside ground conductor of the dielectric substrate formed by extending to the end surface of the dielectric substrate and connecting the backside ground conductor and the conductor film, The electromagnetic field of the microwave propagating through the coplanar line is extended to the end face of the dielectric substrate, and the back surface of the dielectric substrate is grounded. A conductor formed on the dielectric film is concentrated in a predetermined gap between the main conductor and the ground conductor of the coplanar line electrically connected to the plate-shaped conductor by a conductor. It is possible to bring the circuit closer to the coplanar line, and since the electromagnetic field radiated into the space is shielded by the shield component, the thickness of the circuit itself can be reduced and the size can be reduced without changing the transmission characteristics. There is.

According to the sixth aspect of the present invention, since the lumped element is provided in the vicinity of the ground conductor forming the coplanar line, the microwave propagating through the lumped element formed in the coplanar line. Of the electromagnetic field is concentrated in the gap with the ground conductor, and the conductor formed on the dielectric film can be brought closer to the coplanar line or lumped constant element, and the electromagnetic field radiated into the space is shielded. Since it is shielded by the components, there is an effect that the thickness of the circuit itself can be reduced and the size can be reduced without changing the transmission characteristics.

According to the invention described in claim 7, since the photoelectric conversion element for converting the electric signal supplied through the coplanar line into the optical signal is provided, the circuit itself of the circuit itself can be maintained without changing the transmission characteristic. Not only can the thickness be reduced to achieve compactness, but it is also possible to handle optical signals.

According to the invention described in claim 8, since the photoelectric conversion element for converting the optical signal into the electric signal and supplying the electric signal to the coplanar line is provided, the thickness of the circuit itself can be reduced without changing the transmission characteristics. Not only can it be made thinner and more compact, but it can also handle optical signals.

According to the ninth aspect of the present invention, since the optical signal input / output section for inputting / outputting the optical signal to / from the photoelectric conversion element is provided, the thickness of the circuit itself can be reduced without changing the transmission characteristics. Not only can it be made compact, but it is also possible to handle optical signals.

According to the tenth aspect of the present invention, since the coplanar line, the photoelectric conversion element, and the optical signal input / output section are covered with the plate-shaped conductor by the second dielectric made of a transparent material, the transmission characteristic is changed. In addition to reducing the thickness of the circuit itself and realizing compactness, the transmission loss of the optical signal can be reduced and the optical signal can be handled.

According to the eleventh aspect of the present invention, the photoelectric conversion element is provided on the conductor formed on the surface of the silicon substrate arranged on the plate-shaped conductor, and the photoelectric conversion element is provided in the groove formed on the surface of the silicon substrate. Since the optical fiber that inputs and outputs optical signals to the device is provided as the optical signal input and output section, not only can the circuit itself be made thinner and compact, but also the transmission loss of optical signals can be reduced. There is an effect that an optical signal can be handled by the optical fiber.

[Brief description of drawings]

FIG. 1 is a sectional configuration diagram showing a configuration of a microwave circuit according to a first embodiment of the present invention.

FIG. 2 is a characteristic diagram showing changes in the characteristic impedance of the coplanar line with respect to the distance between the coplanar line and the conductor film of the microwave circuit according to the first embodiment of the present invention.

FIG. 3 is a cross-sectional configuration diagram showing a configuration of a microwave circuit according to Reference Example 1 .

FIG. 4 is a sectional configuration diagram showing a configuration of a microwave circuit according to a reference example 2 .

FIG. 5 is a sectional configuration diagram showing a configuration of a microwave circuit according to a second embodiment of the present invention.

FIG. 6 is a sectional configuration diagram showing a configuration of a microwave circuit according to a third embodiment of the present invention.

FIG. 7 is a cross-sectional configuration diagram showing an example of a conventional microwave circuit.

FIG. 8 is a characteristic diagram showing changes in frequency characteristics depending on the presence or absence of a conductor on a microstrip line in a conventional microwave circuit.

[Explanation of symbols]

1 main line (main conductor), 2 ground conductor, 4 first dielectric (dielectric film), 5 dielectric substrate, 6 back side ground conductor (connection conductor), 7 coplanar line, 8 conductor film, 9 second
Dielectric (dielectric film), 10 a plate-like ground conductor (plate conductor), 11 a metal thin film (connection conductor), 12 gold wire Ya,
13 Suruho Le, 14 conductors, 16 spiral inductor (concentrated constant element), 18 a laser diode (photoelectric conversion element), 19 conductor, 20 a silicon substrate,
21 Optical fiber (optical signal input / output section).

Continuation of the front page (56) Reference JP-A-9-46008 (JP, A) JP-A-3-52302 (JP, A) JP-A-2-87701 (JP, A) JP-A-63-238701 (JP , A) Actual development 61-104605 (JP, U) Actual development 63-93663 (JP, U) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01P 3/02 G02B 6/42 H01P 3/08

Claims (11)

(57) [Claims] 1. A back side ground conductor formed on the back side
A dielectric substrate, A main conductor formed on the dielectric substrate and the main conductor;
A ground conductor formed with a predetermined gap.
A planar track, Of the dielectric substrate along the longitudinal direction of the coplanar line
It is provided so as to cover the end face and constitutes the coplanar line.
The ground conductor and the backside ground conductor of the dielectric substrate
A connecting conductor for electrically connecting between A dielectric film covering the coplanar line, Conductor formed on the dielectric film and the backside ground conductor
Including the above as a component part and enclosing the coplanar line
With a shield component configured in, As the dielectric film, a first dielectric and a second dielectric are used.
It covers the coplanar line in layers, The conductor included as a component of the shield component is
The top layer of the dielectric covering the coplanar line in layers
The dielectric substrate is formed on the second dielectric surface, and
Conductor film that is electrically connected to the backside ground conductor Ma
Microwave circuit. 2. The dielectric substrate is electrically connected to a backside ground conductor formed on the backside of the dielectric substrate and is formed on a plate-shaped conductor having a larger area than the dielectric substrate. microwave circuit according to claim 1 Symbol mounting and. 3. The connection conductor is a metal thin film formed so as to cover the end face of the dielectric substrate along the longitudinal direction of the coplanar line, and the conductor film is formed so as to be connected to the metal thin film. 2. The microwave circuit according to claim 1 , wherein the shield component is configured to enclose the coplanar line with the conductor film, the metal thin film, and the back-side ground conductor. 4. The connection conductor is a metal thin film formed so as to cover the end surface of the dielectric substrate along the longitudinal direction of the coplanar line, and the conductor film is formed by being connected to the metal thin film. 3. The microwave circuit according to claim 2 , wherein the constituent portion is configured to enclose the coplanar line with the conductor film, the metal thin film, the backside ground conductor, and the plate conductor. 5. The connection conductor is composed of a back-side ground conductor of the dielectric substrate formed by extending over the end face of the dielectric substrate along the longitudinal direction of the coplanar line so as to cover the end face. , The shield component is formed so as to be connected to the backside ground conductor formed to extend up to the end face of the dielectric substrate, and the shield component is formed to extend to the conductor film and the end face of the dielectric substrate. A structure in which the coplanar line is wrapped with a backside ground conductor.
The microwave circuit according to claim 1 or 2 . 6. The microwave circuit according to claim 5 , wherein the coplanar line includes a lumped constant element formed close to a ground conductor forming the coplanar line. 7. The photoelectric conversion element for converting an electric signal supplied via a coplanar line into an optical signal is provided, and any one of claims 1 to 5 is provided.
The microwave circuit according to the item. 8. The microwave circuit according to claim 1, further comprising a photoelectric conversion element which converts an optical signal into an electric signal and supplies the electric signal to a coplanar line. 9. The method of claim 7, characterized in that it comprises an optical signal output unit for inputting and outputting the optical signal to the photoelectric conversion element also
Is the microwave circuit according to claim 8 . 10. The second dielectric constituting the dielectric film is made of a transparent material that covers the coplanar line, the photoelectric conversion element, and the optical signal input / output section on a plate-shaped conductor.
The microwave circuit according to claim 9 . 11. The photoelectric conversion element is provided on a conductor formed on the surface of a silicon substrate arranged on a plate-shaped conductor, and the optical signal input / output unit is provided in a groove formed on the surface of the silicon substrate. claim 9 or to arranged the photoelectric conversion element, characterized in that an optical fiber for inputting and outputting optical signals
The microwave circuit according to claim 10 .