JP2003218601A - High frequency wiring board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high frequency wiring board by decreasing an electric capacitance caused between an inner layer ground conductor and ground conductors at a lower side formed between both sides of a second coplanar line so as to suppress resonance and reflection of a high frequency signal between the inner layer ground conductor and the ground conductors at the lower side thereby realizing excellent transmission characteristics. <P>SOLUTION: A first coplanar line 5 formed on an upper side of a dielectric board 2 and the second coplanar line 8 formed in parallel with the first coplanar line 5 at the lower side of the dielectric board 2 are arranged across an inner layer ground conductor 9 formed inside of the dielectric board 2 while the tips of the coplanar lines are opposed to each other, the tips of line conductors 3, 6 are electrically connected with each other by a through-conductor 10 insulated from the inner layer ground conductor 9, and a high frequency input output section is constituted so that a plurality of independent conductor non-forming parts 15 is placed at a position apart by 0.3 to 1.5 mm from the through- conductor 10 of the inner layer ground conductor 9. <P>COPYRIGHT: (C)2003,JPO

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for improving electric characteristics.
High-frequency wiring board with a high-frequency input / output section
You. 2. Description of the Related Art Conventionally, high-frequency circuit boards and high-frequency semiconductors
Package for housing element elements, chip for mounting high frequency semiconductor elements
Wiring board for high frequency used for
Lower, also called high-frequency substrate)
High-frequency components such as high-frequency semiconductor devices and their height
The high-frequency circuit of the external electric circuit board on which the
To connect high frequency signal for transmitting high frequency signal
High-frequency transmission lines on the top and bottom
High-frequency input / output section electrically connected with through conductor
Is done. Then, the high-frequency board is used as an external electric circuit board.
The high-frequency transmission line on the bottom
By electrically connecting to the connecting line conductor of the board,
The frequency substrate is mounted and used. [0003] Such a high-frequency substrate is mounted on a high-frequency semiconductor device.
An example of application to a package that implements
There is a package described in Japanese Patent Publication No. 22605502. This
Package consists of a package substrate and this package base.
The package side wall mounted on the board
A lid for sealing the cavity formed by
Mount the semiconductor integrated circuit chip provided in the Viti
The die bonding area and the induction provided in the cavity
Internal high-frequency transmission line consisting of a metal thin film on the surface of an electrical substrate
With a metal thin film on the bottom of the package substrate.
The external coplanar line that forms the lead terminals and the internal height
Electrical connection between frequency transmission line and external coplanar line
Package consisting of via holes made of metal
The internal high-frequency transmission line formed in the cavity
Is composed of a coplanar line,
The metal between the grounded metal of the
Connected by multiple via holes.
It is. According to this, the internal high-frequency transmission line is
Since it was configured as a laner line, its signal and ground metal
By properly selecting the spacing between the lines, the line width of the signal line can be reduced.
Compatible with line width of microstrip line on IC chip
To reduce the loss and reduce the reflection loss.
It can be reduced. In addition, an external coplanar line and an internal high-frequency transmission
The transmission line is made up of multiple via holes and coaxial via holes.
Connection, there is little high-frequency mismatch, and
What can increase isolation
It is. As described above, as a transmission line for high frequency,
Coplanar lines are used because high-frequency substrates
Width of the signal line on the side (top surface) on which the components are mounted
On the side (lower surface) mounted on the external electric circuit board
To compensate for discontinuities with the line width
For the purpose of improving the isolation between
The connection between coplanar lines is more
It is by preference. However, as described in the above-mentioned Japanese Patent No. 2605502,
Of the internal high-frequency transmission line
At the connection between the Rainer line and the via hole
Phase, external coplanar line and via
Between the ground phase at the connection to
The ground between the front and back surfaces is conducted through the
A shift occurred because the route was long. That
Connection between the internal coplanar line and the external coplanar line.
At the connection, reflection of the transmitted high-frequency signal occurs,
There is a problem that reflection loss increases. Therefore, in order to solve the above problems,
For transmitting high-frequency signals formed on the upper surface of a dielectric substrate
And a first coplanar line for
Coplanar line formed in parallel with the coplanar line of
The line and the inner layer ground conductor formed inside the dielectric substrate
And the lines of both coplanar lines
Through conductor in which the ends of the path conductors are insulated from the inner layer ground conductor
And both coplanar lines from the through conductor
At a position of 0.2 to 5 mm on both sides in a direction orthogonal to
The ground conductors of both coplanar lines are
Electrically connected by electrically connected ground through conductors
A device having a frequency input / output unit has been proposed (Japanese Patent Laid-Open No.
01-177012). [0009] However, the above-mentioned problem is not solved.
In the high-frequency substrate described in JP 2001-177012 A
Is the first coplanar line on the upper surface of the dielectric substrate and the inner layer ground.
Penetrates the conductor and the second coplanar line on the lower surface of the dielectric substrate
Conductor, but the inner layer ground conductor and the second core
With the ground conductor on the lower surface side formed on both sides of the planar line
The gap between the inner layer ground conductor and the lower side ground conductor
Increases electrical capacity between the body and high-frequency signals
There has been a problem that electromagnetic interference and coupling are likely to occur.
As a result, between the inner-layer ground conductor and the second coplanar line,
The high frequency signal transmitted by the
There was a problem that loss increased. Accordingly, the present invention has been made in view of the above-mentioned conventional problems.
It is completed and its purpose is to
Grounding conductors on the lower side formed on both sides of the second coplanar line.
Reduce the electrical capacitance between the body and the inner layer ground conductor.
Suppresses resonance and reflection of high-frequency signals with the ground conductor on the bottom side
To have good transmission characteristics.
You. [0011] The high-frequency wiring base of the present invention
The plate transmits high-frequency signals formed on the upper surface of the dielectric substrate
A first coplanar line for performing
A second lower surface formed in parallel with the first coplanar line.
And forming two coplanar lines inside the dielectric substrate.
With the tips facing each other across the grounded inner conductor
And the tip of the line conductor of both coplanar lines
Are electrically connected to each other with a through conductor insulated from the inner layer ground conductor.
Connected to the through conductor of the inner layer ground conductor from 0.3 to
Multiple independent conductor-free parts are installed at 1.5 mm apart.
And a high-frequency input / output unit. The high-frequency wiring board of the present invention has an inner layer grounding conductor.
Independent multi-layers at a distance of 0.3 to 1.5 mm from the conductor
Because the number of conductor-free parts provided is
Grounding conductors on the lower side formed on both sides of the second coplanar line.
While reducing the electric capacity that occurs between the body and
In particular, a through conductor between the inner layer ground conductor and the ground conductor on the lower side
Can greatly reduce the electrical capacity around the
Between the ground conductor and the ground conductor on the lower side, the through conductor and its surroundings
Significantly reduce the electrical capacitance between the conductors
be able to. As a result, the inner layer ground conductor
Electromagnetically converts high-frequency signals transmitted through conductors between conductors
Interference and coupling are less likely to occur,
The reflection can be greatly suppressed, and the reflection loss can be suppressed. Further, the inner layer ground conductor and the lower surface side ground conductor
The internal capacitance is reduced because the electrical capacitance generated during
Reduce the spacing between the conductor and the ground conductor on the bottom side
The size of the high-frequency substrate can be reduced. DESCRIPTION OF THE PREFERRED EMBODIMENTS The high-frequency substrate of the present invention will be described below.
This will be described in detail. FIG. 1 shows the high-frequency substrate of the present invention.
FIG. 1A shows an example of an embodiment, and FIG.
Top view of high frequency input / output unit, (b) is AA 'line of (a)
(C) is a sectional view taken along line BB ′ of (a).
Sectional view, (d) is a plan view of the inner-layer ground conductor, (e) is a high circumference
It is a bottom view of the high frequency input / output part of a wave board. In FIG. 1, 1 is a high-frequency substrate, and 2 is a dielectric substrate.
The substrate 3 is a high-frequency signal formed on the upper surface of the dielectric substrate 2.
1 is a first line conductor for transmitting a signal, and 4 is a first line conductor.
A first ground conductor formed on both sides of the body 3;
A first coplanar line is formed by the line conductor 3 and the first ground conductor 4.
Road 5 is configured. 6 is provided on the lower surface of the dielectric substrate 2.
Of the first line conductor 3 so as to face the end of the first line conductor 3.
A second line conductor formed in parallel with the first line conductor 3,
Reference numeral 7 denotes second ground conductors formed on both sides of the second line conductor 6.
A second line conductor 6 and a second ground conductor 7
Two coplanar lines 8 are configured. In this example,
Forming two first and second coplanar lines 5, 8
I have. Reference numeral 9 designates a first inside of the dielectric substrate 2.
Facing the coplanar line 5 and the second coplanar line 8
Inner layer ground conductor formed so that the first line conductor
The tip of the body 3 and the tip of the second line conductor 6 are electrically connected.
And the through conductor 10 is different from the inner layer ground conductor 9.
It is electrically insulated. Thus, the shape is formed on the upper surface of the dielectric substrate 2.
The first coplanar line 5 thus formed and the lower part of the dielectric substrate 2
The second coplanar line 8 formed on the surface is
With the inner layer ground conductor 9 formed inside the plate 2 interposed,
And the coplanar lines 5,
The line conductors 3 and 6 of FIG.
Connected to form a high-frequency input / output unit of the high-frequency substrate 1.
You. In this high frequency input / output unit, the second line conductor 7 is
Also serves as a mounting electrode for connection to the electric circuit board. In the present invention, the inner layer ground conductor 9
And is electrically connected to the
On both sides in a direction orthogonal to the second coplanar lines 5, 8,
Ground conductors 4, 7 of the first and second coplanar lines 5, 8
It is preferable to provide a ground through conductor 11 for electrically connecting the conductor.
Suitable. With this configuration, the first and second coplanar wires
The connecting portions of the paths 5 and 8 are connected to the through conductor 10 and the inner layer grounding conductor 9.
Has electrical characteristics close to a coaxial structure due to the through conductor 11
To reduce high frequency mismatch
Thus, the reflection loss can be reduced. Also, the inner layer ground conductor
Ground conductor of body 9 and first and second coplanar lines 5 and 8
4 and 7 are connected by the ground through conductor 11,
At the connection between the second line conductors 3 and 6 and the through conductor 10
It is possible to equalize the phases of the ground to eliminate the deviation.
And suppresses reflection of high-frequency signals to reduce reflection loss
Can be In this example, the first upper surface of the dielectric substrate 2
The first ground conductor 4 and the second ground conductor 7 on the lower surface are respectively
Extending around the ends of these line conductors 3 and 6.
This allows for a better grounding condition
You. Reference numeral 12 is bonded to the upper surface of the dielectric substrate 2.
M is a half formed on the upper surface of the dielectric substrate 2.
It is a mounting part for electronic components such as conductor elements. Like this
By providing the mounting portion M and the frame 12, the high-frequency substrate 1
The package for electronic component storage that houses electronic components for high frequency
Can be used as di. For example, such a high-frequency substrate 1
Is manufactured by a ceramic green sheet laminating method or the like.
In this case, the dielectric substrate 2 may include a plurality of dielectric layers.
It is formed by laminating 2a and 2b. At this time, the dielectric layer
By setting 2a and 2b to an appropriate thickness, the inner layer
The position of the ground conductor 9, that is, the inner layer ground conductor 9 and the first and second cups
The distance from the laner lines 5 and 8 is determined by the required characteristics of the high frequency
Desired settings can be made according to the characteristics. In particular, the position where the inner-layer ground conductor 9 is formed is
The distance from the first coplanar line 5 is the second coplanar line
If it is set to be smaller than the distance to Road 8,
The second coplanar with the speedy matching
The width of the line conductor 6 of the line 8 can be increased,
This is preferable because the attachment strength of the terminal increases. In the present invention, the through conductor of the inner layer ground conductor 9 is used.
Multiple independent conductors 0.3 to 1.5 mm away from body 10
A non-formed portion 15 is provided. Through conductor 10 and conductor non-formed part 15
If the distance from the conductor is less than 0.3 mm,
Capacitive component and inductive component (self-inducing
Of the conductive component). Then, Impey
Loss of matching between capacitive and inductive components suitable for dance matching
Therefore, a resonance point is likely to appear. Through conductor 10
And the distance between the conductor non-formed portion 15 is 1.5 mm or less and 1.5 m
m, the electromagnetic coupling between the through conductor 10 and the inner layer ground conductor 9
Depending on the case, the capacitance component and the induction component (self-induction component)
The induction component increases. Then, it is suitable for impedance matching.
The matching between the inductive component and the capacitive component
Is likely to appear. The shape of the non-conductor-formed portion 15 is circular, elliptical,
Various shapes such as a polygon such as a quadrangle can be used.
In addition, the size of the conductor non-formed portion 15 is the diameter when the shape is circular.
Is preferably 0.05 to 0.5 mm. Less than 0.05mm
Is used for electromagnetic coupling between the second line conductor 6 and the inner layer ground conductor 9.
From the capacity component and the induction component (self-induction component),
Ingredients increase. Then, it is suitable for impedance matching
The matching between the capacitive component and the inductive component is impaired, and the resonance point
It is easy to be. If it exceeds 0.5 mm, the second line
Electromagnetic coupling between the path conductor 6 and the inner-layer ground conductor 9 causes capacitance
The induction component increases in the minutes and the induction component (self-induction component)
You. Then, a capacitance component suitable for impedance matching and induction
Matching with the conducting component is lost, and a resonance point appears.
Easy. The high-frequency substrate 1 is connected to an external electric circuit.
While mounted on the upper surface of the substrate, the second line conductor 6 is
To the connection line conductor of the external electric circuit board and the second grounding conductor.
The body 7 is connected to the ground conductor of the external electric circuit board with a solder bump.
Using conductive connecting members such as
Electrical connection by the reflow process
Thus, the high-frequency board 1 is mounted on the external electric circuit board. Next, an embodiment of the high-frequency substrate of the present invention will be described.
Another example of the configuration is shown in FIG. FIG. 2A shows a high-frequency substrate.
(B) is an AA ′ line in (a) of FIG.
(C) is a cross-sectional view taken along the line BB ′ of (a).
(D) is a plan view of the inner-layer ground conductor, and (e) is a high-level view.
It is a bottom view of the high frequency input / output part of a frequency substrate. FIG.
In FIG. 1, the same parts as those in FIG.
The detailed description of is omitted. In FIG. 2, reference numeral 13 denotes an auxiliary ground through conductor.
The first ground conductor 4 on the upper surface of the dielectric substrate 2 and the
The second ground conductor 7 is connected to the tip of the first and second line conductors 3 and 6.
It is provided so as to surround the edge, and a better grounding condition
Obtainable. In addition, the auxiliary ground through conductor 13 is
The through conductor 10 and the shortest distance conductor in the ground conductor 9
The through conductor 10 has a distance approximately equal to the distance from the non-formed portion 15.
From the first ground conductor 4 and the inner layer.
The ground conductor 9 and the second ground conductor 7 are electrically connected.
You. According to such a high-frequency substrate 1 of the present invention,
For example, in the high frequency input / output unit, the first and second coplanar
The connection between the lines 5 and 8 is connected to the through conductor 10 and the inner layer ground conductor 9.
Has electrical characteristics close to a coaxial structure due to the ground penetrating conductor 11
To reduce high frequency mismatch
The reflection loss can be reduced. Also, the first and second
The ground at the connection between the line conductors 3 and 6 and the through conductor 10
Can be eliminated by equalizing the phase of the
The reflection loss of the frequency signal can be suppressed by suppressing the reflection of the frequency signal.
You. And, by providing the conductor non-formed portion 15, the penetration
The electric capacity around the conductor 10 can be greatly reduced,
Electromagnetic interference or coupling occurs in the high-frequency signal transmitted by the body 10.
It is difficult to generate and greatly suppresses resonance and reflection of high frequency signals
Thus, reflection loss can be suppressed. Also, the dielectric substrate
2 effectively suppresses leakage of high-frequency signal electromagnetic fields
Can reflect the high frequency signal in the high frequency input / output section
Loss can be further suppressed. Further, the first and second ground conductors 4 and 7 are
Extending around the ends of the first and second line conductors 3 and 6, respectively.
In the case of providing, the through conductor 10 is formed from the first coplanar line 5.
Via the second coplanar line 8 or vice versa
Capacitance to minimize loss when transmitting high frequency signals
Adjusting the components to form the first and second ground conductors 4, 7;
The conductor non-formed portion 15 is formed on the inner-layer ground conductor 9. This and
And the resistance, inductor, and capacitance match all over the signal line.
And first and second ground conductors 4, 7 and conductors
It is preferable to form the non-formed portion 15 by adjusting the position. Then, such a high-frequency substrate 1 of the present invention
Is mounted on the upper surface of the external electric circuit board, and the second
The line conductor 6 is used as a connection line conductor of the external electric circuit board.
The second ground conductor 7 to the ground conductor of the external electric circuit board.
By conductive connection members such as solder bumps, respectively; or
Electrical connection by reflow process using solder material
As a result, the high-frequency board 1 is mounted on the external electric circuit board.
Be mounted. Next, an embodiment of the high-frequency substrate of the present invention will be described.
Another example of the configuration is shown in FIG. FIG. 3A shows a high-frequency substrate
(B) is an AA ′ line in (a) of FIG.
(C) is a cross-sectional view taken along the line BB ′ of (a).
(D) is a plan view of the inner-layer ground conductor, and (e) is a high-level view.
It is a bottom view of the high frequency input / output part of a frequency substrate. FIG.
In FIG. 1, the same parts as those in FIG.
The detailed description of is omitted. In FIG. 3, the inner-layer ground conductor 9 is connected to the inner layer.
The dielectric substrate 2 is composed of two layers, that is, the ground conductors 9a and 9b.
Of dielectric layers 2a, 2b, and 2c. Inner layer ground conductor 9
a and the inner-layer ground conductor 9b are connected by the intermediate ground through conductor 14.
Has been continued. With this configuration, the contact around the through conductor 10 is
Strongly formed earth potential wall, more coaxial structure
By adopting a pseudo-coaxial structure close to
The transmission performance can be improved to reduce the transmission loss. In this configuration
Between the inner-layer ground conductor 9 a and the first coplanar line 5.
The distance between the inner layer ground conductor 9b and the second coplanar line 8
It is good to set it to be smaller than the distance of
In this case, impedance matching becomes easier
The width of the second line conductor 6 can be increased, and the lead end
The attachment strength of the child will increase. The length of the intermediate ground through conductor 14 is 50 μm to 0.5
mm is good, and if it is less than 50 μm, it is too short and difficult to manufacture.
If it exceeds 0.5 mm, the distance between the inner-layer ground conductors 9a and 9b
Since the separation is long, the ground potential is likely to be unstable. Further, the first ground conductor 4 is connected to the inner layer on the upper layer side.
The length of the ground through conductor 11 that connects to the ground conductor 9a is 50 μm
0.5 μm is good, and if it is less than 50 μm, the first line conductor 3
The inner-layer ground conductor 9a comes close to the
, A capacitance component occurs, and for impedance matching,
It is necessary to reduce the width of the wiring conductor of the high-frequency substrate 1. So
Then, the connection between the mounted semiconductor element and the high-frequency substrate 1
The reflection of the high-frequency signal tends to increase in the section. More than 0.5mm
As a result, the size of the high-frequency substrate 1 increases. Second
A connection for connecting the ground conductor 7 to the lower inner-layer ground conductor 9b
The length of the ground through conductor 11 is preferably 50 μm to 0.5 mm, and 50 μm
If it is less than the above, the width of the wiring conductor of the high-frequency substrate 1 is narrow as in the above.
And it is difficult to join lead terminals for external connection
become. If it exceeds 0.5 mm, the wiring conductor of the high-frequency substrate 1
And the high-frequency substrate 1 becomes large.
You. FIG. 4 shows an embodiment of the high-frequency substrate 1 of the present invention.
FIG. 3 shows another example of the embodiment, and in the configuration of FIG.
The auxiliary ground through conductor 13 shown in FIG. 2 is provided. In FIG.
(A) is a top view of the high-frequency input / output unit of the high-frequency substrate 1,
(B) is a cross-sectional view taken along line AA ′ of (a), and (c) is
(A) is a cross-sectional view taken along the line BB ', (d) is an inner layer ground.
FIG. 5E is a plan view of a conductor, and FIG.
It is a bottom view. In FIG. 4, the same parts as those in FIG.
Reference numerals are used, and their detailed description is omitted. With this configuration, the through conductor 10 and its surroundings are
By using a pseudo-coaxial structure close to the coaxial structure, high-frequency signals
Transmission characteristics of the first and second line conductors.
Dielectric substrate extending from the tip of 3, 6 to the extension direction of the transmission direction
It is possible to effectively suppress the leakage of the high-frequency signal into the plate 2.
To reduce the reflection loss of high-frequency signals in the high-frequency input / output section.
Can be suppressed. The length of the auxiliary ground through conductor 13 is
The same range for the same reason as in the case of the ground through conductor 11 in FIG.
Is good. The high frequency band referred to in the present invention is 1 to
A high frequency band of about 100 GHz and a millimeter wave band,
Therefore, the high-frequency substrate 1 of the present invention has a high frequency of about 1 to 100 GHz.
It is used in frequency band and millimeter wave band,
Use in a relatively low frequency band of about 1 to 80 GHz
Is preferred. It is in the high frequency band over 80GHz
High frequency signals are more susceptible to external magnetic fields,
This leads to an increase in size and loss. More preferred
Preferably, it is used at about 1 to 65 GHz. The present invention is not limited to the above embodiment.
Without departing from the scope of the present invention.
It is not a problem to change or improve. For example,
In the above embodiment, the first and second coplanar lines 5,
8 is provided for each two, but the coplanar
When one line is provided or three or more lines are provided.
It may be a case of multiple ports. Inner layer ground conductors 9a, 9
Regarding b, in the above embodiment, two layers are provided.
However, three or more layers may be provided. Also, co-play
The lead conductors and conductor bumps (conductor conductors)
) With a conductive member for connection
good. Embodiments of the high-frequency wiring board of the present invention will be described below.
This will be described in detail. An embodiment of the high-frequency wiring board of the present invention will be described.
Therefore, the high-frequency wiring board 1 of FIG.
Was. Alumina (Al _Two O _Three ) Dielectric consisting of ceramics
Two layers are provided on the upper surface of the dielectric substrate on which the layers 2a, 2b, and 2c are stacked.
The first coplanar line 5 is formed, and the first
Two second coplanar lines 8 parallel to the Lener lines 5
Formed. Also, between the dielectric layer 2a and the dielectric layer 2b
Formed the inner-layer ground conductor 9. First coplanar line 5
Of the first line conductor 3 and the second coplanar line
8 and the tip of the second line conductor 6 from the via hole
Are electrically connected by the through conductor 10. Also, the first cup
The first ground conductor 4 and the second co-pres
And the second ground conductor 7 forming the transmission line 8 is connected to the ground through conductor 11.
Was electrically connected. This ground through conductor 11 is shown in FIG.
As shown in (d), the two conductors perpendicular to the transmission
The pseudo-coaxial structure is provided by
I made it. The first coplanar line 5, the second
Coplanar line 8, through conductor 10, ground through conductor 11, and
The inner-layer ground conductor 9 is made of gold containing Mo—Mn as a metal component.
Ceramic green sea as a dielectric substrate
Apply or fill the specified area and through hole of
It was formed by firing simultaneously with the Mick Green sheet. Then, as shown in FIG.
The distance from the through conductor 10 near the through conductor 10 of the ground conductor 9 is
From the through conductor 10 to the second line conductor in the range of 0.3 to 2.0 mm
A circular conductor with a diameter of 0.05 mm is placed on the part located above
Twenty non-formed portions 15 were formed. Also, the ground conductor and the through conductor 10
The distance from the conductor 11 is about 0.25 mm, and the thickness of the dielectric layer 2a is
About 0.3 mm, the thickness of the dielectric layer 2 b is about 0.3 mm,
The thickness of 2c was about 0.3 mm. As a comparative example, the conductor non-formed portion 15 is not provided.
Except for the above, a conventional one constructed in the same manner as the above
did. With respect to the above embodiment, the frequency range of 1 to 65 GHz
High frequency signal is input, and 1-40
High frequency signals of GHz are input and their S11 (reflection characteristics)
Characteristics: reflection loss) and S21 (transmission characteristics: insertion loss).
FIG. 5 shows the results obtained by the simulation. FIG.
Thus, in the case of the comparative example, since resonance occurred at 35 GHz, S
21 increased, but the resonance point of the embodiment was 6
Shifted to 2.5 GHz to obtain good transmission characteristics over a wide band
Was. In the embodiment, S11 has a maximum of 33 dB (15 GH).
z) Improved and reduced return loss over a wide band
On the other hand, in the comparative example, S11 has a maximum of 29 dB (1 GHz).
z), but S11 in a wide band of 10 to 40 GHz
The reflection loss was increased to 15 dB or less. The present invention is not limited to the above-described embodiment and embodiment.
The present invention is not limited to the example, and does not depart from the gist of the present invention.
Various changes can be made within the above range. The high frequency wiring board of the present invention has a dielectric substrate.
The first for transmitting the high frequency signal formed on the upper surface of the plate
And a first coplanar line on the lower surface of the dielectric substrate.
A second coplanar line formed parallel to the
Between the inner-layer ground conductor formed inside the dielectric substrate.
With both ends facing each other,
The ends of the line conductors are insulated from the inner layer ground conductor.
Electrically connected by the through conductor
Multiple conductors separated from each other by 0.3 to 1.5 mm or more
That it has a high-frequency input / output unit with a non-forming part
The inner ground conductor and the second coplanar line on both sides.
Electric capacity generated between the ground conductor on the lower side
In particular, and especially the contact between the inner layer ground conductor and the lower side
Significantly increases the electrical capacity around the through conductor between the ground conductor
Between the inner layer ground conductor and the ground conductor on the lower side.
Between the through conductor and the surrounding conductor
The capacity can be significantly reduced. As a result, the inner layer
Transmission between the ground conductor and the ground conductor on the bottom
Electromagnetic interference and coupling to high-frequency signals
Greatly reduces the resonance and reflection of high-frequency signals,
Can be suppressed. Also, the inner layer ground conductor and the lower surface side ground conductor
The internal capacitance is reduced because the electrical capacitance generated during
Reduce the spacing between the conductor and the ground conductor on the bottom side
And the size of the high-frequency wiring board is reduced.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an example of an embodiment of a high-frequency wiring board according to the present invention, in which (a) is a top view of a high-frequency input / output unit of the high-frequency wiring board, and (b) is (a). ) Is a sectional view taken along line AA ′, (c) is a sectional view taken along line BB ′ in (a),
(D) is a plan view of the inner-layer ground conductor, and (e) is a bottom view of the high-frequency input / output unit of the high-frequency wiring board. FIGS. 2A and 2B show another example of the high-frequency wiring board according to the embodiment of the present invention, in which FIG. 2A is a top view of a high-frequency input / output unit of the high-frequency wiring board, and FIG. (C) is a cross-sectional view taken along line BB ′ of (a),
(D) is a plan view of the inner-layer ground conductor, and (e) is a bottom view of the high-frequency input / output unit of the high-frequency wiring board. 3A and 3B show another example of the embodiment of the high-frequency wiring board according to the present invention, wherein FIG. 3A is a top view of a high-frequency input / output unit of the high-frequency wiring board, and FIG. 3B is AA of FIG. (C) is a cross-sectional view taken along line BB ′ of (a),
(D) is a plan view of the inner-layer ground conductor, and (e) is a bottom view of the high-frequency input / output unit of the high-frequency wiring board. 4A and 4B show another example of the embodiment of the high-frequency wiring board according to the present invention, in which FIG. 4A is a top view of a high-frequency input / output section of the high-frequency wiring board, and FIG. (C) is a cross-sectional view taken along line BB ′ of (a),
(D) is a plan view of the inner-layer ground conductor, and (e) is a bottom view of the high-frequency input / output unit of the high-frequency wiring board. FIG. 5 is a graph showing a result obtained by simulating a reflection loss (S11) and an insertion loss (S21) for the high-frequency wiring board of FIG. 1 according to the present invention; [Description of Symbols] 1: Wiring board for high frequency 2: Dielectric substrate 3: First line conductor 4: First ground conductor 5: First coplanar line 6: Second line conductor 7: Second ground Conductor 8: Second coplanar line 9, 9a, 9b: Inner layer ground conductor 10: Through conductor 11: Ground through conductor 15: Conductor non-formed portion

Claims (1)

Claims: 1. A first coplanar line formed on an upper surface of a dielectric substrate for transmitting a high-frequency signal, and a lower surface of the dielectric substrate is formed in parallel with the first coplanar line. The formed second coplanar line is disposed with its ends facing each other across an inner layer ground conductor formed inside the dielectric substrate, and the ends of the line conductors of both coplanar lines are connected to the inner layer. A high-frequency input / output unit electrically connected by a through conductor insulated from a ground conductor and provided with a plurality of independent conductor non-forming portions at a portion of the inner layer ground conductor separated from the through conductor by 0.3 to 1.5 mm. A high-frequency wiring board, characterized in that: