JP2002198708A - High frequency wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve a problem in a conventional high frequency wiring board that the ground potential becomes unstable due to a resistance and an inductive component by a distance between a conductive connection member and a through-conductor on the same face ground conductor so as to cause mismatching of the characteristic impedance resulting in increased reflection loss. SOLUTION: The high frequency wiring board of this invention has an input output section provided with a ground conductor 3 formed on a lower face of a dielectric board 2, a signal line 4 for high frequency signal transmission formed on an upper face of the dielectric board 2, the same face ground conductor 5 formed on both sides of and around the signal line 4, 1st through-conductors 6 that are formed to the same face ground conductor 5 to electrically connect the same face ground conductor 5 to a ground conductor 3, and an external connection use conductive connection member 8 respectively placed at ends of the signal line 4 and the same face ground conductor 5. The shortest distance between the conductive connection member 8 connected to the same face ground conductor 5 and a 2nd through-conductor 7 formed closest to the conductive connection member 8 is 1/4 the wavelength of a high frequency signal transmitted through the signal line 4 or below.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-frequency wiring board for connecting high-frequency circuit components or high-frequency circuit devices such as ICs and LSIs used in a high-frequency band, and more particularly to a coplanar circuit having improved transmission characteristics of high-frequency signals. The present invention relates to a high-frequency wiring board having a line structure.

[0002]

2. Description of the Related Art In recent years, high-frequency wiring boards for mounting high-frequency circuit parts include wiring boards that have a small reflection loss of high-frequency signals as the operating speed and the frequency of high-frequency circuit parts such as ICs and LSIs increase. It has been demanded.

Conventionally, a microstrip line structure and a coplanar line structure are often used as wiring boards for transmitting high-frequency electric signals. In particular, low return loss,
Since low radiation loss is required, a high-frequency wiring board having a coplanar line structure is generally used. A high-frequency wiring board having a coplanar line structure is one in which a signal line is formed on a dielectric substrate, and a ground conductor on the same plane is formed on both sides of the signal line at a predetermined interval. A ground conductor is also formed on the back side of a high-frequency wiring board having a coplanar structure, and a coplanar line with a back-side ground conductor, in which the same-side ground conductor on the front and back surfaces and the ground conductor are electrically connected by through conductors, is often used. Then, it is connected to a high-frequency circuit component or a high-frequency circuit device via a conductive connection member.

In the input / output portion of such a conventional high frequency wiring board having a coplanar line structure, there is no through conductor in the vicinity of the input / output portion for electrically connecting the same plane ground conductor and the ground conductor. There is a problem that a mismatch in characteristic impedance occurs at the input / output part of the wiring board for use, and the reflection loss in a high frequency range is larger than that in a low frequency range.

Therefore, as a technique for matching the characteristic impedance of the input / output section of the high-frequency wiring board, for example, a ground conductor 13 formed on the lower surface of the dielectric board 12 as shown in FIGS. A signal line 14 for high-frequency signal transmission formed on the upper surface of the dielectric substrate 12, a coplanar ground conductor 15 provided on both sides of the signal line 14, and a coplanar ground conductor 15 and a ground conductor 13 formed by a through conductor 16. It is of a configuration to connect. In the input / output section of the high-frequency wiring board 11, a long groove-shaped through conductor 16 is formed from the end face to the vicinity of the end face. As a result, a coplanar line with a backside grounded conductor is formed, and electrical connection with high-frequency circuit components and high-frequency circuit devices is performed via a signal line 14 and a conductive connection member 18 provided at an end of the same-plane grounded conductor 15. Done. By forming the above-mentioned configuration, that is, forming the long groove-shaped through conductor 16 from the end face of the high-frequency wiring board 11 to the vicinity of the end face, the value of the characteristic impedance in the input / output section can be matched over a wide frequency range, and the high-frequency signal A device capable of improving transmission characteristics has been proposed (Japanese Patent Laid-Open No. 10-1998).
2003011).

[0006]

However, in the conventional high-frequency wiring board 11 having the input / output section provided with the conductive connection member 18 for external connection, the through-hole as shown in FIGS. In the case where the conductor 16 is used, the conductive connecting member 18 and the through conductor in the ground conductor 15 on the same plane in a high frequency band such as a microwave band and a millimeter wave band.
As a result, the ground potential becomes unstable due to the conduction resistance and inductance component between the input and output terminals, resulting in the emission of electromagnetic waves due to the mismatch of characteristic impedance and the increase in the reflection loss of high-frequency signals at the input and output sections of the coplanar line. However, there is a problem that transmission characteristics are deteriorated.

Accordingly, the present invention has been made in view of the above problems, and an object of the present invention is to form a coplanar line in an input / output section of a high frequency wiring board for connecting a high frequency circuit component and a high frequency circuit device. -Frequency wiring board having an input / output section with good transmission characteristics over a wide band, which can suppress electromagnetic wave radiation due to characteristic impedance mismatch due to the distance between the conductive connecting member and the through conductor in the same plane ground conductor. Is to provide.

[0008]

A high-frequency wiring board according to the present invention comprises: a ground conductor formed on a lower surface of a dielectric substrate; a signal line for transmitting high-frequency signals formed on an upper surface of the dielectric substrate; A same-plane ground conductor formed on both sides and around the signal line, a first through conductor formed in the same-plane ground conductor, and electrically connecting the same-plane ground conductor to the ground conductor; In a high-frequency wiring board having an input / output unit including a signal line and an external connection conductive connection member provided at each end of the same-plane ground conductor, the high-frequency wiring board connected to the same-plane ground conductor The shortest distance between the conductive connection member and the second through conductor formed closest to the conductive connection member is not more than の of the wavelength of the high-frequency signal transmitted through the signal line. I do.

According to the present invention, radiation of an electromagnetic wave due to characteristic impedance mismatch can be suppressed by setting the distance between the conductive connecting member and the through conductor within the same plane ground conductor to a predetermined distance or less. . As a result, a high-frequency wiring board having an input / output section having good transmission characteristics over a wide band is obtained.

The high-frequency wiring board according to the present invention is preferably arranged such that the plurality of first and second wirings are arranged at a distance equal to or less than half of the wavelength from the conductive connecting member provided on the same-surface ground conductor. Wherein the average value of the shortest distance connecting each of the first and second through conductors and the conductive connection member is not more than ４ of the wavelength.

With such a configuration, a plurality of the first and second through conductors are formed in a range where the distance from the conductive connecting member is equal to or less than a half of the wavelength. Over, radiation of electromagnetic waves can be further suppressed. As a result, a high-frequency wiring board having an input / output section having good transmission characteristics over a wider band is obtained.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a high-frequency wiring board according to the present invention will be described with reference to the drawings.

FIGS. 1 and 2 are a perspective view and a plan view, respectively, showing an embodiment of a high-frequency wiring board according to the present invention.
1 is a high frequency wiring board, 2 is a dielectric board, and has a ground conductor 3 on the lower surface. 4 is a signal line, 5 is a ground conductor on the same plane formed on both sides of the signal line 4, and 6 is a first through conductor connecting the ground conductor 5 and the ground conductor 3 on the same plane. Thereby, the ground conductor 5 on the same plane as the signal line 4
The ground conductor 3 and the ground conductor 3 constitute a coplanar line section. Then, the connection with the high-frequency circuit component or the high-frequency circuit device is performed via the conductive connection member 8 provided at the input / output end of the high-frequency wiring board 1 of the signal line 4 and each of the ground conductors 5 on the same plane. .

In the high-frequency wiring board 1 of the present invention, as shown in FIGS.
, The shortest distance (pitch between the conductive connecting member 8 and the second through conductor 7) L1 between the conductive connecting member 8 and the second through conductor 7 formed closest to the conductive connecting member 8 is ４ of the wavelength. It is as follows. Preferably, the conductive connecting member 8 in each of the same-plane ground conductors 5, the first and second through conductors 6,
The average value of the shortest distances L1 and L2 connecting each of the first and second through conductors 6 and 7 and the conductive connection member 8 in a range where the shortest distance to the distance 7 is a half or less of the wavelength ( L
1 + L2) / 2 is one-fourth or less of this wavelength. When there are n through conductors (n is an integer of 2 or more), the average value of the shortest distances L1, L2, to Ln is (L1 + L2 + to + Ln) / n.

With the above arrangement, the input / output portion with the high-frequency wiring board 1 for connecting high-frequency circuit components and high-frequency circuit devices, which are problematic in a high frequency band such as a microwave band or a millimeter wave band, has a coplanar structure. The conductive connecting member 8 and the first
In addition, the ground potential does not become unstable due to the conduction resistance and the inductance component due to the distance from the second through conductors 6 and 7, the characteristic impedance is matched, and good high-frequency signal transmission characteristics in the coplanar line portion can be realized.

Next, FIGS. 3 to 6 show plan views of other embodiments of the high-frequency wiring board 1 of the present invention.

In FIGS. 3 to 6, the same parts as those in FIG.
1 shows a plan view seen from the upper surface side of FIG. In these figures, 1 is a high-frequency wiring board, 2 is a dielectric substrate, 4 is a signal line formed on the surface of the dielectric substrate 2, 5 is a same-plane ground conductor formed on both sides of the signal line 4, 6 Is a first through conductor that electrically connects the same plane ground conductor 5 and the ground conductor 3 (not shown), and 7 is a second through conductor closest to the conductive connection member 8. is there. A coplanar line section formed by the signal line 4 and the ground conductor 5 on the same plane connects to a high-frequency circuit component or a high-frequency circuit device.

In the high-frequency wiring board 1 of FIG. 3, the same-surface ground conductor 5 is formed so as to surround the signal line 4.
The first and second through conductors 6 and 7 for connecting the ground conductor 3 and the same-plane ground conductor 5 are also formed so as to surround the signal line 4 similarly to the same-plane ground conductor 5. The first and second through conductors 6 and 7 are formed inside the conductive connection member 8 (on the signal line 4 side). Second through conductor 7
Are formed close to the inside of the conductive connection member 8.

With the above configuration, at the input / output portion with the high-frequency wiring board 1, the conductive connection member 8 and the first and second through conductors 6 in the same plane ground conductor 5 constituting the coplanar line are provided. , 7 does not become unstable due to the conduction resistance and the inductance component, and the characteristic impedance can be matched. Since the first and second through conductors 6 and 7 are formed inside the conductive connection member 8 so as to surround the signal line 4, the radiation of the electromagnetic wave is suppressed, and the good coplanar line portion is provided. Transmission characteristics of a high-frequency signal can be realized.

In the high-frequency wiring board 1 shown in FIG. 4, the same-surface ground conductor 5 is formed so as to surround the signal line 4.
The first and second through conductors 6 and 7 for connecting the ground conductor 3 and the same-plane ground conductor 5 are also formed so as to surround the signal line 4 similarly to the same-plane ground conductor 5. The first and second through conductors 6 and 7 are formed outside the conductive connection member 8. The second through conductor 7 is formed close to the outside of the conductive connection member 8.

With the above configuration, in the input / output section of the high-frequency wiring board 1, the first and second conductive connecting members 8 in the same-plane ground conductor 5 forming the coplanar line are connected.
(2) The grounding potential due to the conduction resistance and the inductance component due to the distance from the through conductors 6 and 7 does not become unstable, and the characteristic impedance can be matched. By forming the first and second through conductors 6 and 7 outside the conductive connection member 8 so as to surround the signal line 4, radiation of electromagnetic waves is suppressed. When the line width of the signal line 4 and the gap between the signal line 4 and the ground conductor 5 on the same side on both sides become fine with an increase in the number of connection terminals of the high-frequency circuit components and the high-frequency circuit device, the first And the second through conductor 6,
7 is also to be formed at a narrow interval, the high-frequency wiring board
Although the strength of 1 is reduced and the formation becomes difficult, the configuration of FIG. 4 maintains the strength and provides the same effect as that of FIG. Therefore, good transmission characteristics of a high-frequency signal in the coplanar line section can be realized.

In the high-frequency wiring board 1 shown in FIG. 5, the same-surface ground conductor 5 is formed so as to surround the signal line 4.
The first and second through conductors 6 and 7 connecting the ground conductor 3 and the same-plane ground conductor 5 are also formed so as to surround the signal line 4 similarly to the same-plane ground conductor 5. The first and second through conductors 6 and 7 are formed doubly on the inside and outside of the conductive connecting member 8, and the first through conductor 6 on the outside is
The inner first and second through conductors 6 and 7 are formed at positions corresponding to the approximate center positions of the respective pitches. The second through conductor 7 is formed close to the inside of the conductive connection member 8.

With the above configuration, at the input / output portion with the high-frequency wiring board 1, the conductive connection member 8 and the first and second through conductors 6 in the same plane ground conductor 5 constituting the coplanar line are provided. , 7 does not become unstable due to the conduction resistance and the inductance component, and the characteristic impedance can be matched. The first and second through conductors 6 and 7 are formed double on the inside and outside of the conductive connecting member 8, and the first and second through conductors are alternately formed.
Are arranged at substantially the center positions of the respective pitches of the through conductors 6 and 7 so as to surround the periphery of the signal line 4. Thereby, the first and second through conductors 6 and 7 are set to 1
It is possible to obtain substantially the same effect as the configuration in which the pitch is narrowed by the double structure, and it is possible to prevent the strength of the high frequency wiring board 1 from lowering than the configuration in which the pitch is narrowed by the single structure.
Therefore, the radiation of the electromagnetic wave is further suppressed while maintaining the strength of the high-frequency wiring board 1. As a result, good transmission characteristics of a high-frequency signal in the coplanar line section can be realized.

In the high-frequency wiring board 1 of FIG. 6, a notch is formed on the side of the dielectric substrate 2 on the input / output end side of the high-frequency wiring board 1 as the first through conductor 6, and the notch is formed. In which a castellation conductor is formed in which a conductor layer such as a metallized layer is formed. As described above, the first through conductor 6 is not limited to a through hole having a circular cross section, but penetrates the upper and lower surfaces of the dielectric substrate 2 or cuts out the side surface to conduct. Further, first and second through conductors 6 and 7 for connecting the ground conductor 3 and the same-plane ground conductor 5 are formed on both left and right sides of the signal line 4. The conductive connecting member 8 is provided in the input / output end of the signal line 4 and in the same plane ground conductor 5 close to the input / output end so as to be arranged in a direction substantially perpendicular to the line direction of the signal line 4. I have. The second through conductor 7 is formed near the conductive connection member 8 in a direction substantially parallel to the line direction of the signal line 4.

With the above configuration, in the input / output section of the high-frequency wiring board 1, the conductive connecting member 8 and the first and second through conductors 6, 7 within the same plane ground conductor 5 constituting the coplanar line are provided. And the ground potential due to the inductance component and the inductance component do not become unstable, and the characteristic impedance can be matched. Further, since the castellation conductor is formed on the side surface of the dielectric substrate 2 on the input / output end side of the high-frequency wiring board 1 as the first through conductor 6, the castellation conductor becomes the conductive connection member 8. This has the same effect as the configuration in which the third and fourth through conductors 20 and 21 having a small diameter are formed outside on the outside close to. That is, the third and fourth penetrating conductors 20 and 21 have the same effect as performing impedance control in the input / output section of the high-frequency wiring board 1 with high accuracy. Also, the third
Since it is difficult to form the fourth through conductors 20 and 21 in a narrow area such as the input / output section in order to maintain the strength, high-precision impedance control is performed while maintaining the strength of the high-frequency wiring board 1. Can do it.

Therefore, a stable ground potential can be realized while maintaining the strength of the high-frequency wiring board 1, and precise matching of the characteristic impedance in the vicinity of the input / output section of the high-frequency wiring board 1 can be performed. In addition, the first substrate formed on the side surface of the dielectric substrate 2
Of the through conductor 6 can be easily adjusted in width, for example, by increasing the width to reduce the conductor resistance and the inductance component. As a result, good transmission characteristics of a high-frequency signal in the coplanar line section can be realized.

As described above, the arrangement and shape of the coplanar ground conductor 5, the first through conductor 6, and the second through conductor 7 may be variously changed.

In the high-frequency wiring board 1 of the present invention, as the dielectric substrate 2, for example, a ceramic material such as alumina ceramic or mullite ceramic, an inorganic material such as glass ceramic, or an ethylene tetrafluoride resin (polytetrafluoroethylene) is used. PTFE), ethylene tetrafluoride-ethylene copolymer resin (tetrafluoroethylene-ethylene copolymer resin; ETFE), ethylene tetrafluoride-perfluoroalkoxyethylene copolymer resin (tetrafluoroethylene-perfluteroalkyl vinyl ether copolymer) Resin materials such as fluororesin such as resin; PFA), glass epoxy resin, and polyimide are used. The shape and dimensions (thickness, width, and length) of these dielectric substrates 2 are set according to the frequency and characteristic impedance of the high-frequency signal used.

The signal line 4 of the present invention is formed by applying a Ni plating layer and an Au plating layer on a conductor layer of a metal material for transmitting a high-frequency signal, for example, a Cu layer, a Mo—Mn metallization layer, and a W layer. Ni plating layer and A on the metallized layer
u-plated layer, Cr-Cu alloy layer, Cr
Those obtained by depositing a Ni plating layer and an Au plating layer on the -Cu alloy layer, which was deposited a Ni-Cr alloy layer and an Au plating layer on the Ta ₂ N layer, Pt layer on the Ti layer and an Au Formed by a thick film printing method, various thin film forming methods, plating methods, etc., using a plating layer adhered or a Pt layer and an Au plating layer adhered on a Ni-Cr alloy layer. Is done. The thickness and width are also set according to the frequency and characteristic impedance of the transmitted high-frequency signal.

The same-plane ground conductor 5 may be formed of the same material as the signal line 4 by the same method, and the distance between the signal line 4 and the same-plane ground conductor 5 depends on the frequency and characteristics of the transmitted high-frequency signal. It is set according to impedance or the like.

The ground conductor 3 may be formed by using the same material as the signal line 4 and the same-plane ground conductor 5 by the same method. In addition to the case where it is formed as a conductor layer,
It may be formed by attaching another conductive member, for example, a metal plate or a metal block.

The first through conductor 6 and the second through conductor 7 are formed so as to connect the ground conductor 5 and the ground conductor 3 on the same plane, for example, by forming a through-hole conductor or a via-hole conductor. , Or metal plates and bars,
It may be formed by burying a metal pipe or the like.

The number of the first and second through conductors 6 and 7 formed at a distance of not more than half the wavelength from the conductive connection member 8 is preferably 2 to 4 in the same plane ground conductor 5. . When the number of the first and second through conductors 6 and 7 is more than four, the area of the same-plane ground conductor 5 which is a region where the first and second through conductors 6 and 7 are formed increases, and the dielectric substrate 2 The area also becomes large, and as a result, it becomes difficult to reduce the size of the high-frequency circuit component or the high-frequency circuit device. If one is used, the conductor resistance and inductance of the through conductor become large, so that the ground potential becomes unstable and impedance mismatch occurs.

In manufacturing the high-frequency wiring board 1 of the present invention, for example, when the dielectric substrate 2 is made of alumina ceramic, first, a green sheet of alumina ceramic to be the dielectric substrate 2 is prepared, Of the first and second through conductors 6, 7
Is formed by screen printing,
A through hole is filled with a conductive paste such as Mo or Mo, and a predetermined signal line 4 pattern and other conductive layer patterns are printed and applied. Next, baking is performed at 1600 ° C., and finally, Ni plating and Au plating are performed.

Such a high-frequency wiring board 1 is used by connecting the signal line 4 and the ground conductor 5 on the same plane to a high-frequency circuit component and a high-frequency circuit device by means of a conductive connecting member 8. It functions for impedance matching between an external drive circuit, a control circuit, and the like, a high-frequency circuit component and a high-frequency circuit device.

Thus, the present invention has an operational effect that a good high-frequency signal can be transmitted in a wide band.

[0037]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the high-frequency wiring board of the present invention will be described below.

(Embodiment) The lower surface of a dielectric substrate 2 made of alumina ceramics having a relative dielectric constant of 8.6 and having a thickness of 0.2 mm is used as the high-frequency wiring substrate 1 of the present invention shown in FIGS. Was formed on almost the entire surface of the substrate, a ground conductor 3 formed by laminating a Ni plating layer and an Au plating layer on the W metallized layer. On the upper surface of the dielectric substrate 2, a line conductor having a line width of 0.15 mm as the signal line 4 and having a Ni plating layer and an Au plating layer laminated on the W metallization layer was formed.

A ground conductor 5 on the same plane was formed on both sides of the signal line 4 with an interval of 0.12 mm. First through conductor 6
The second through conductor 7 is made of W metallized, has a cross section of a circle having a diameter of 0.1 mm and an ellipse having a width of 0.1 mm, and has a signal line 4 extending in a direction orthogonal to the transmission direction of the high-frequency signal.
Were formed by arranging two on each side. The distance L3 between the first and second through conductors 6, 7 was 0.4 mm.
The conductive connecting member 8 is provided on the input / output end of the signal line 4 and on the signal line 4 side adjacent to the second through conductor 7, and the conductive connecting member 8 and the second through conductor 7 are connected to each other. Was 0.1 mm, and the shortest distance L2 between the conductive connecting member 8 and the first through conductor 6 was 0.5 mm. Three conductive connecting members 8 are provided at the input end and the output end of the signal line 4, respectively, and are arranged at a distance of 0.25 mm in a direction orthogonal to the transmission direction of the high-frequency signal. Thus, a sample A of the high-frequency wiring board 1 of the present invention was obtained.

On the other hand, as a comparative example, as shown in FIGS. 8 and 9, the dielectric substrate 12, the signal line 14,
The ground conductor 13 and the same-plane ground conductor 15 were formed. Through conductor 16
Is made of W metallized and has an oval width of 0.1 mm. The conductive connecting member 18 is disposed on the through conductor 16 at a distance of 0.5 mm in a direction orthogonal to the transmission direction of the high-frequency signal,
A sample B as a conventional high-frequency wiring board 11 was produced.

High-frequency Wiring Board of the Present Invention and Comparative Example
The conductive connection members 8 and 18 were used for the samples A and B
Was connected to a network analyzer using a wafer probe, and the reflection loss with respect to a high-frequency signal of each of the samples A and B was measured. The result of the return loss is shown in FIG.

FIG. 7 is a graph showing the reflection loss of a high-frequency signal in the high-frequency wiring boards 1 and 11 of the present invention and the comparative example. The horizontal axis represents the frequency (GHz), and the vertical axis represents the reflection loss (dB). It represents. In the characteristic curves, the solid line indicates the reflection loss of the sample A, and the broken line indicates the reflection loss of the sample B.

From these results, it was found that the sample B had 30 GH
The reflection loss increases from the vicinity of exceeding z, and its value is -10
It was over dB. On the other hand, in sample A, 1 to 100 GHz
No characteristic deterioration was observed in the frequency range of
At about Hz, the reflection loss is about -25 dB or less,
At about 100 GHz, good characteristics were obtained with a reflection loss of about 15 dB or less.

Therefore, according to the high-frequency wiring board 1 of the present invention, the shortest distance between the conductive connecting member 8 and the second through conductor 7 closest to the conductive connecting member 8 in each ground conductor 5 on the same plane is four minutes of the wavelength. 1 (0.85-0.32m at 30-80GHz
m) and the average value of the shortest distances between the conductive connecting member 8 and each of the first and second through conductors 6 and 7 in each ground conductor 5 is equal to or less than one quarter of the wavelength. In the high frequency band of the microwave band or even the millimeter wave band, the coplanar line forming the coplanar line is formed at the input / output portion with the high frequency wiring board 1 for connecting the high frequency circuit components and the high frequency circuit device. The instability of the ground potential due to the conduction resistance and the inductance component due to the distance between the conductive connection member 8 and the first and second through conductors 6 and 7 in the conductor 5 is eliminated. In addition, it was confirmed that matching of the characteristic impedance was achieved, and good transmission characteristics of a high-frequency signal in the coplanar line portion could be realized.

It should be noted that the present invention is not limited to the above embodiment, and various changes may be made without departing from the spirit of the present invention. For example, in the above-described embodiment, an example in which a wafer probe is used as the conductive connection member 8 has been described. However, as long as the conductive connection member 8 is electrically connected, a ball, a bump, a lead, a bonding wire,
It may be a ribbon wire.

[0046]

According to the present invention, a ground conductor formed on the lower surface of a dielectric substrate, a signal line for transmitting high-frequency signals formed on an upper surface of the dielectric substrate, and both sides and around the signal line are formed. A plurality of coplanar ground conductors and a plurality of coplanar ground conductors are formed to electrically connect the coplanar ground conductor to the ground conductor.
In a high-frequency wiring board having an input / output unit including a through conductor of 1 and a conductive connection member for external connection provided at each end of a signal line and a ground conductor on the same plane,
The shortest distance between the conductive connecting member connected to the same plane ground conductor and the second penetrating conductor formed closest to the conductive connecting member is a quarter of the wavelength of the high-frequency signal transmitted through the signal line. By setting the distance below, the distance between the conductive connecting member and the through conductor within the same plane ground conductor is set to be equal to or less than a predetermined value, so that the radiation of the electromagnetic wave due to the characteristic impedance mismatch can be suppressed. As a result, a high-frequency wiring board having an input / output section having good transmission characteristics over a wide band is obtained.

The present invention preferably has a plurality of first and second through conductors at a distance of one-half wavelength or less from a conductive connecting member provided on the same plane ground conductor. The average value of the shortest distance between each of the through conductors 2 and the conductive connecting member is equal to or less than ４ of the wavelength, so that the distance from the conductive connecting member is equal to or less than 波長 of the wavelength. Since the plurality of first and second through conductors are formed, it is possible to further suppress the emission of electromagnetic waves around the conductive connecting member. As a result, a high-frequency wiring board having an input / output section having good transmission characteristics over a wider band is obtained.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of a high-frequency wiring board according to the present invention.

FIG. 2 is a plan view of the high-frequency wiring board of FIG. 1;

FIG. 3 is a plan view of another embodiment of the high-frequency wiring board of the present invention.

FIG. 4 is a plan view showing another embodiment of the high-frequency wiring board of the present invention.

FIG. 5 is a plan view showing another embodiment of the high-frequency wiring board of the present invention.

FIG. 6 is a plan view showing another embodiment of the high-frequency wiring board of the present invention.

FIG. 7 is a graph showing reflection loss in the high-frequency wiring board of the present invention.

FIG. 8 is a perspective view of a conventional high-frequency wiring board.

FIG. 9 is a plan view of a conventional high-frequency wiring board.

[Explanation of symbols]

 1: high frequency wiring board 2: dielectric substrate 3: ground conductor 4: signal line 5: ground conductor 6: first through conductor 7: second through conductor 8: conductive connecting member

Claims (2)

[Claims] 1. A ground conductor formed on a lower surface of a dielectric substrate, a signal line for transmitting high-frequency signals formed on an upper surface of the dielectric substrate, and a same surface contact formed on both sides and around the signal line. A ground conductor, a plurality of first through-conductors formed on the same-plane ground conductor, and electrically connecting the same-plane ground conductor to the ground conductor; and a first end of the signal line and the same-plane ground conductor, respectively. In a high-frequency wiring board having an input / output unit provided with a provided conductive connection member for external connection, the conductive connection member connected to the same-plane ground conductor and the closest to the conductive connection member. A shortest distance from the formed second through conductor is not more than one-fourth of a wavelength of a high-frequency signal transmitted through the signal line. 2. A plurality of the first and second through conductors at a distance of not more than half of the wavelength from the conductive connection member provided on the same plane ground conductor, wherein the first and second through conductors are provided. No. 2
2. The high-frequency wiring board according to claim 1, wherein the average value of the shortest distance between each of the through conductors and the conductive connection member is 以下 or less of the wavelength. 3.