JPH0946008A - Wiring board for high frequency - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a wiring board for high frequency which has no possibility to detrimentally affect a high frequency signal which is transmitted to a signal line by a stub existing in an end part of a ground pattern. SOLUTION: A ground pattern 30 is provided to an insulation board 10 parallel to a signal line 20. An end part 30b of a ground pattern electrically connected to a ground 50 provided to the insulation board 10 facing the signal line 20 and the ground pattern 30 through a plurality of conductor vias 40 provided to the insulation board 10 is positioned in an inner side of an end part 10a of an insulation board. A distance L between the end part 30b of a ground pattern and a ground pattern part 30a electrically connected to a conductor via 40 which is nearest to the end part is formed to be less than 1/4 of a wavelength λ of high frequency signal transmitted to a signal line 20.

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 having a signal line for transmitting a high frequency signal of 5 to 10 GHz or higher.

[0002]

2. Description of the Related Art With the recent increase in operating speed and frequency of semiconductor chips, there has been a demand for a high-frequency wiring board for mounting a semiconductor chip, which has a signal line for efficiently transmitting a high-frequency signal with less transmission loss.

As signal lines used for this high-frequency wiring board, signal lines having a coplanar line structure with a ground and a signal line having a pseudo-rectangular coaxial line structure are known.

The signal line having the coplanar line structure with ground is, as shown in FIG. 13, a signal line 2 provided on an insulating substrate 10 made of ceramic or plastic.
A strip-shaped ground pattern 30 is provided on both sides of the signal line 2
It is provided side by side with 0 at a predetermined interval.

The ground pattern 30 is widely spread in parallel with the signal line 20 and the ground pattern 30 on a portion of the insulating substrate 10 above or below the signal line 20 and the ground pattern 30 (the lower surface of the insulating substrate 10 in the figure). The grounds 50 arranged in layers are electrically connected to each other via a plurality of columnar conductor vias 40. Specifically, the portion of the ground pattern 30 inside the end portion 30b of the ground pattern is electrically connected to the ground 50 via a plurality of conductor vias 40. The conductor via 40 is provided on the insulating substrate 10 portion immediately below the ground pattern 30.
A plurality of 0s are vertically penetrated and arranged side by side at a small pitch. The signal line 20 is formed as a coplanar line with ground.

The signal line having the pseudo rectangular coaxial line structure is
As shown in FIG. 14, on the insulating substrate 10 portion above and below the signal line 20 provided on the insulating substrate 10 formed of ceramic or plastic or the like (the upper surface and the lower surface of the insulating substrate 10 are shown in the figure). , Ground pattern 30
Are arranged in parallel in a wide layer in parallel with the signal line 20. The ground pattern 3 is formed above and below the signal line 20.
Surrounded by 0.

The ground pattern 30 provided above and below the signal line 20 is the same as the ground pattern 30 constituting the ground provided below and above the signal line 20.
It is electrically connected via a plurality of conductor vias 40. In other words, the ground patterns 30 provided above and below the signal line 20 are electrically connected to each other via the plurality of columnar conductor vias 40 that are provided side by side on both sides of the signal line 20. Specifically, the ground patterns 3 above and below the end 30b of the ground pattern
The 0 portion is electrically connected to each other via a plurality of conductor vias 40. The conductor vias 40 are provided in a portion of the insulating substrate 10 sandwiched between the upper and lower ground patterns 30 so as to vertically penetrate the insulating substrate 10 and are arranged side by side at a small pitch. Then, a plurality of conductor vias 4 are provided on both sides of the signal line 20.
Surrounded by 0. The signal line 20 is formed into a pseudo rectangular coaxial line.

In the signal line 20 having the coplanar line structure with a ground or the pseudo-rectangular coaxial line structure, the signal line 20 is electrically connected to the ground provided side by side at a small pitch on the insulating substrate 10 portion on the side of the signal line 20. The plurality of conductor vias 40 thus formed prevent the high-frequency signal transmitted through the signal line 20 from passing between the adjacent conductor vias 40 on the side of the signal line 20 and mixing with other signal lines 20. do.

Here, in order to prevent the high-frequency signal transmitted through the signal line 20 from passing through between the adjacent conductor vias 40 on the side of the signal line 20 and mixing into another signal line 20,
As described in Japanese Patent Publication No. 5-86859, the pitch of a plurality of conductor vias 40 arranged side by side in the insulating substrate 10 on the side of the signal line 20 is transmitted to the signal line 20 by the wavelength λ of the high-frequency signal. It is known that it should be shorter than this.

[0010]

However, in a wiring board having a signal line having a coplanar line structure with a ground or a pseudo-rectangular coaxial line structure, as described above, the insulating substrate 10 on the side of the signal line 20 is provided horizontally. Even when the pitch of the plurality of conductor vias 40 arranged side by side is set to be shorter than the wavelength λ of the high frequency signal transmitted to the signal line 20, the high frequency signal of 5 to 10 GHz or more is still sufficiently transmitted to the signal line 20 with little transmission loss and efficiency. I couldn't communicate well.

In pursuit of the cause, in the signal line 20, as shown in FIG. 13 or 14, a conductor via 40 forming a ground in a ground pattern portion 30a inward from the end of the ground pattern 30 is formed. The end of a ground pattern called a stub 60 that is not electrically connected directly to the ground outside the ground pattern portion 30a that is electrically connected to the conductor via 40. It has been found that 30b is present and the stub 60 lowers the lowest resonant frequency value of the signal line 20. It was found that the stub 60 hinders transmission of the high frequency signal to the signal line 20 with a small transmission loss.

The reason is that if the stub 60 is present at the end portion 30b of the ground pattern, the high frequency signal transmitted to the signal line 20 leaks to the stub 60 and the stub 60 is leaked.
It is presumed that this is because it is mixed again in the signal line 20 through the.

The same is true of the case where a part of the signal line 20 provided on the insulating substrate 10 made of ceramic or plastic or the like, as shown in FIG. It has been found that the same can be applied to a wiring board in which the ground pattern 30 is locally arranged side by side with respect to the signal line 20 in the insulating substrate 10 part and a characteristic impedance of a part of the signal line 20 is matched to a predetermined value. .

In this wiring board, the ground pattern 30 is placed on the side of the insulating board 1 opposite to the signal line 20.
It is electrically connected via a plurality of columnar conductor vias 40 to a ground 50, which is arranged in a wide layer in parallel with the ground pattern 30 in the 0 portion (the lower surface of the insulating substrate 10 in the figure). Specifically, the portion of the ground pattern 30 that is inside the end portion 30b of the ground pattern is electrically connected to the ground 50 through the plurality of conductor vias 40. A plurality of conductor vias 40 are provided side by side in the vertical direction on the insulating substrate 10 portion immediately below the ground pattern 30. The characteristic impedance of a part of the signal line 20 is matched with a predetermined value of 50Ω or the like.

That is, also in such a wiring board, the portion of the ground pattern 30 which is located inside the end portion 30b of the ground plane is electrically connected to the ground 50 through the plurality of conductor vias 40, and the conductor vias are formed. A ground pattern end 30b called a stub 60 exists outside the ground pattern portion 30a electrically connected to 40, and prevents the stub 60 from transmitting a high frequency signal to the signal line 20 with a small transmission loss. There was found.

Conventionally, there is known a wiring board in which the end portion 30b of the ground pattern is directly electrically connected to the ground 50 and the stub 60 is excluded from the end portion 30b of the ground pattern.

In this wiring board, as shown in FIG. 16, a line 70 made of metallization or the like is provided on the end face of the insulating substrate 10, and the end 30b of the ground pattern is connected to the ground 50 or the ground via the line 70. Is electrically connected to the ground pattern 30 constituting the. Alternatively, as shown in FIG. 17, a half conductor via 80 formed by vertically dividing a columnar conductor via made of metallization or the like is provided at an end portion of the insulating substrate 10, and a ground pattern is provided via the half conductor via 80. End portion 30b is electrically connected to the ground 50 or the ground pattern 30 forming the ground.

However, in this wiring board,
A great deal of labor and time are required for the work of forming the line 70 made of metallization or the like on the end surface of the insulating substrate 10 by a side surface printing method or the like or forming the half conductor via 80 made of metallization or the like on the end portion of the insulating substrate 10. Needed

With the recent trend toward miniaturization and high density of semiconductor devices, the lines 70 are formed side by side on the end face of the insulating substrate 10 with a minimum width and a minimum pitch, and the half conductor vias 80 are insulated. It is necessary to form sideways on the end portion of the substrate 10 with a minimum diameter and a minimum pitch.
There is a risk that a great deal of labor and skill will be required to form the half conductor via 80 and the line 70 or the half conductor via 80 may be electrically short-circuited to another line 70 or the half conductor via 80 adjacent thereto. There was.

Therefore, as a result of various tests conducted by the present inventors, in each of the above wiring boards, a high frequency for transmitting the length L of the stub 60 existing at the end 30b of the ground pattern to the signal line 20. If it is formed to be less than 1/4 of the signal wavelength λ, the adverse effect of the stub 60 existing at the end portion 30b of the ground pattern can be eliminated, and the signal line 20 can be provided with a 5
It has been discovered that a high frequency signal of 10 GHz or more can be efficiently transmitted with less transmission loss.

Based on the finding, a wiring board was developed in which the stub 60 existing at the end 30b of the ground pattern does not adversely affect the high frequency signal transmitted to the signal line 20.

At the same time, it is a wiring board in which the stub 60 which may adversely affect the high frequency signal transmitted to the signal line 20 is eliminated from the end portion 30b of the ground pattern.
We have developed a wiring board that is easy to manufacture.

That is, an object of the present invention is to provide a high-frequency wiring board (hereinafter referred to as a wiring board) in which the stub existing at the end of the ground pattern does not adversely affect the high-frequency signal transmitted to the signal line. There is.

Another object of the present invention is to provide a wiring board in which a stub that may adversely affect a high frequency signal transmitted to a signal line is eliminated from the end of the ground pattern and which is easy to manufacture. .

[0025]

In order to achieve the above object, the first wiring board of the present invention has a plurality of conductors provided on the insulating board with a ground pattern provided on the insulating board side by side with the signal line. In the wiring board electrically connected to the ground via the via, the end of the ground pattern is located inward of the end of the insulating substrate, and the end of the ground pattern is closest to the end. Distance L between a ground pattern portion electrically connected to the conductor via
Is 1/4 of the wavelength λ of the high frequency signal transmitted to the signal line.
It is characterized in that it is formed to be less than or equal to zero.

Then, the distance L between the end of the ground pattern and the ground pattern portion electrically connected to the conductor via closest to the end, that is, the length L of the stub is transmitted to the signal line. It is formed to be shorter than 1/4 of the wavelength λ to eliminate the adverse effect of the stub on the high frequency signal transmitted to the signal line. Alternatively, the stub is excluded from the end of the ground pattern. The high frequency signal can be transmitted to the signal line with a small transmission loss.

A second wiring board of the present invention is a wiring board in which a ground pattern provided on an insulating substrate in parallel with a signal line is electrically connected to the ground through a plurality of conductor vias provided on the insulating substrate. In the wiring board in which the end of the ground pattern is extended to the end of the insulating substrate, the ground pattern electrically connected to the end of the ground pattern and the conductor via closest to the end It is characterized in that the distance L to the portion is formed to be less than ¼ of the wavelength λ of the high frequency signal transmitted to the signal line and larger than zero.

Then, the distance L between the end of the ground pattern and the ground pattern portion electrically connected to the conductor via closest to the end, that is, the length L of the stub, of the high frequency signal transmitted to the signal line. It is formed to be shorter than 1/4 of the wavelength λ to eliminate the adverse effect of the stub on the high frequency signal transmitted to the signal line. The high frequency signal can be transmitted to the signal line with a small transmission loss.

In the first or second wiring board of the present invention, the ground pattern forms the signal line in the coplanar line, or the ground pattern forms the signal line in the pseudo rectangular coaxial line. It is preferable that the ground layer or the ground pattern for this is a local ground plane for matching the characteristic impedance of a part of the signal line with a predetermined value.

Further, it is preferable that the ground is made to face the signal line and the ground pattern so as to have a wide layered structure on the insulating substrate.

It is preferable that a wide layered ground can prevent the high-frequency signal transmitted to the signal line from leaking to the outside of the ground. It is also preferable that the ground pattern can be electrically connected to a wide layered ground facing the ground pattern via a plurality of conductor vias with a short distance and a small ground potential difference.

[0032]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a preferred embodiment of the first wiring board of the present invention, and is a partial perspective view thereof in detail.
The first wiring board will be described below.

In the first wiring board shown in the figure, the band-shaped ground pattern 30 provided on both sides of the signal line 20 is provided with an end portion 30b of the ground pattern for forming the signal line 20 in a coplanar line structure with a ground. , Is located inward of the end 10a of the insulating substrate. Then, the end portion 30b of the ground pattern and the conductor via 4 closest to the end portion 30b
The distance L to the ground pattern portion 30a electrically connected to 0, that is, the length L of the stub 60 is
It is formed to be, for example, ⅛λ within a range of less than ¼ of the wavelength λ of the high-frequency signal transmitted to 0 or zero.

Others are the same as those of the wiring board having the signal line having the coplanar line structure with ground shown in FIG. 13, and in the first wiring board,
It is possible to eliminate the adverse effect of the stub 60 existing at the end portion 30b of the ground pattern on the high frequency signal transmitted to the signal line 20, and to transmit the high frequency signal of 5 to 10 GHz or higher to the signal line 20 with a small transmission loss. Alternatively, the length L of the stub 60 existing at the end 30b of the ground pattern
Is zero, that is, the stub 60 is eliminated from the end 30b of the ground pattern, and a high frequency signal of 5 to 10 GHz or higher can be transmitted to the signal line 20 with a small transmission loss.

FIG. 2 shows a preferred embodiment of the second wiring board according to the present invention, more specifically, a partial perspective view thereof. The second wiring board will be described below.

In the wiring board shown in the figure, an end portion 30b of the band-shaped ground pattern 30 provided on both sides of the signal line 20 for forming the signal line 20 in a coplanar line structure with a ground is provided with an insulating substrate. End 1
It extends to 0a. Then, a distance L between the end portion 30b of the ground pattern and the ground pattern portion 30a electrically connected to the conductor via 40 closest to the end portion,
That is, the length L of the stub 60 is formed to be, for example, ⅛λ within a range that is less than ¼ of the wavelength λ of the high-frequency signal transmitted to the signal line 20 and greater than zero.

Others are the same as those of the wiring board having the signal line having the coplanar line structure shown in FIG. 13, and in this second wiring board, the stubs existing at the end 30b of the ground pattern are provided. 60 is the signal line 20
It is possible to eliminate adverse effects on the high frequency signal transmitted to the signal line 20 and transmit the high frequency signal of 5 to 10 GHz or higher to the signal line 20 with a small transmission loss.

FIG. 3 shows another preferred embodiment of the first wiring board of the present invention, more specifically, a partial perspective view thereof.
The first wiring board will be described below.

In the first wiring board shown in the figure, the ground pattern 30 is provided above and below the signal line 20, and the end portion of the ground pattern for forming the signal line 20 in the pseudo rectangular coaxial line structure. 30b is located inward of the end 10a of the insulating substrate. Then, the distance L between the end portion 30b of the ground pattern and the ground pattern portion 30a electrically connected to the conductor via 40 closest to the end portion, that is, the length L of the stub 60 is transmitted to the signal line 20. It is formed to be, for example, 1 / 8λ within a range of less than ¼ of the wavelength λ of the high frequency signal or zero.

Others are the same as those of the wiring board having the signal line having the pseudo-rectangular coaxial line structure shown in FIG. 14, and in the first wiring board, the wiring board is present at the end 30b of the ground pattern. The stub 60 is the signal line 2
It is possible to eliminate the adverse effect on the high frequency signal transmitted to 0 and transmit the high frequency signal of 5 to 10 GHz or more to the signal line 20 with a small transmission loss. Alternatively, by removing the stub 60 from the end 30b of the ground pattern, the signal line 20
In addition, a high frequency signal of 5 to 10 GHz or more can be transmitted with less transmission loss.

FIG. 4 shows another preferred embodiment of the second wiring board of the present invention, and is a partial perspective view thereof in detail.
The second wiring board will be described below.

In the wiring board shown in the figure, the ground pattern 30 is provided above and below the signal line 20, and the end portion 30b of the ground pattern for forming the signal line 20 in the pseudo rectangular coaxial line structure is provided. End 10a of insulating substrate
Has been extended to. And the end 3 of the ground pattern
0b and the distance L between the ground pattern portion 30a electrically connected to the conductor via 40 closest to the end, that is, the length L of the stub 60 is 1 of the wavelength λ of the high frequency signal transmitted to the signal line 20. It is formed to be, for example, ⅛λ within a range of less than / 4 and greater than zero.

Others are the same as those of the wiring board having the signal line having the pseudo-rectangular coaxial line structure shown in FIG. 14, and in this second wiring board, the wiring board is present at the end 30b of the ground pattern. The stub 60 is the signal line 2
It is possible to eliminate the adverse effect on the high frequency signal transmitted to 0 and transmit the high frequency signal of 5 to 10 GHz or more to the signal line 20 with a small transmission loss.

FIG. 5 shows another preferred embodiment of the first wiring board according to the present invention, which is a partial side sectional view thereof in detail. The first wiring board will be described below.

In the first wiring board of the figure, below a part of the signal line 20 or above it (it is referred to as a lower side in the figure).
A ground pattern 30 locally arranged laterally with respect to the signal line 20 on the insulating substrate 10 part of the above, the outer end of the ground pattern for matching the characteristic impedance of a part of the signal line 20 to a predetermined value. 30b
Are located inward of the end 10a of the insulating substrate.
Then, the distance L exists between the outer end portion 30b of the ground pattern and the ground pattern portion 30a electrically connected to the conductor via 40 closest to the end portion, that is, at the outer end portion 30b of the ground pattern. Length of stub 60 L
1/4 of the wavelength λ of the high frequency signal transmitted to the signal line 20
It is formed to, for example, 1 / 8λ within the range of less than or equal to zero.

In addition, the inner end 30 of the ground pattern
b is retracted inward of the ground pattern 30.
The distance L exists between the inner end portion 30b of the ground pattern and the ground pattern portion 30a electrically connected to the conductor via 40 closest to the end portion, that is, at the inner end portion 30b of the ground pattern. Length of stub 60 L
1/4 of the wavelength λ of the high frequency signal transmitted to the signal line 20
It is formed to, for example, 1 / 8λ within the range of less than or equal to zero.

Other than that, the signal line 2 shown in FIG. 15 is used.
The ground pattern 30 is provided below or above a part of 0.
Is locally provided and is configured in the same manner as a wiring board in which a characteristic impedance of a part of the signal line 20 is matched to a predetermined value. In the first wiring board, an end outside the ground pattern and an end inside the ground pattern are formed. It is possible to eliminate the adverse effect of the stub 60 existing in the portion 30b on the high frequency signal transmitted to the signal line 20, and to transmit the high frequency signal of 5 to 10 GHz or higher to the signal line 20 with a small transmission loss. Alternatively, the end portion 30b outside or inside the ground pattern
5 to 10G on the signal line 20 by removing the stub 60 from the
It is possible to transmit a high frequency signal of Hz or higher with less transmission loss.

FIG. 6 shows another preferred embodiment of the second wiring board of the present invention, and is a partial side sectional view thereof in detail. The second wiring board will be described below.

In the second wiring board shown in the figure, it is below a part of the signal line 20 or above it (the lower side in the figure).
A ground pattern 30 locally arranged laterally with respect to the signal line 20 on the insulating substrate 10 part of the above, the outer end of the ground pattern for matching the characteristic impedance of a part of the signal line 20 to a predetermined value. 30b
Is extended to the end portion 10a of the insulating substrate. And
The distance L between the outer end portion 30b of the ground pattern and the ground pattern portion 30a electrically connected to the conductor via 40 closest to the end portion, that is, the stub 60 existing at the outer end portion 30b of the ground pattern. Is formed to be, for example, ⅛λ within a range of less than ¼ of the wavelength λ of the high frequency signal transmitted to the signal line 20 and larger than zero.

Others are the same as those of the first wiring board shown in FIG. 5, and in this wiring board, the stubs 60 existing on the outer and inner ends 30b of the ground pattern are the signal lines. It is possible to eliminate adverse effects on the high-frequency signal transmitted to the signal line 20, and to transmit a high-frequency signal of 5 to 10 GHz or higher to the signal line 20 with a small transmission loss. Alternatively, the stub 60 can be eliminated from the inner end 30b of the ground pattern, and a high frequency signal of 5 to 10 GHz or higher can be transmitted to the signal line 20 with a small transmission loss.

The present invention is a wiring board having a microstrip line structure in which a ground pattern is provided above or below the signal line, and an end portion of the ground pattern for forming the microstrip line is formed. It can also be used for a wiring board in which the inner ground pattern portion is electrically connected to the ground through a plurality of conductor vias.

That is, in such a wiring board, the end portion of the ground pattern for forming a microstrip line provided above or below the signal line is located inside the end portion of the insulating substrate, and the ground pattern is formed. Of the distance L between the end of the ground pattern and the ground pattern portion electrically connected to the conductor via closest to the end, that is, the length L of the stub existing at the end of the ground pattern to the signal line. It may be formed to be less than ¼ of the signal wavelength λ or zero. Alternatively, a ground pattern for forming a microstrip line provided above or below the signal line,
The distance L between the end of the ground pattern extending to the end of the insulating substrate and the ground pattern portion electrically connected to the conductor via closest to the end, that is, the stub existing at the end of the ground pattern. It is sufficient to form the length L of less than ¼ of the wavelength λ of the high frequency signal transmitted to the signal line and greater than zero. Then, it is preferable to eliminate the adverse effect of the stub existing at the end of the ground pattern on the high-frequency signal transmitted to the signal line, or to eliminate the stub from the end of the ground pattern.

Further, the ground 50 is preferably provided in a wide layered manner on the insulating substrate 10 so as to face the signal line 20 and the ground pattern 30. Then, it is preferable that the wide layered ground 50 can accurately prevent the high-frequency signal transmitted to the signal line 20 from leaking to the outside of the ground 50. In addition, a plurality of conductor vias 4 are connected to the ground pattern 30 with a wide layered ground 50 facing the ground pattern 30.
It is advisable to be electrically connected via 0 via a short distance and a small ground potential difference. Then, it is preferable that the ground pattern 30 can be accurately brought close to the ground potential.

[0054]

Experimental Example FIGS. 8 to 12 show measured comparison data of high-frequency signal transmission characteristics of the signal line between the first wiring board of the present invention having a signal line having a coplanar line structure and a conventional wiring board. There is.

In the wiring board used for obtaining these comparison data, as shown in FIG. 7, the width provided on the upper surface of the insulating substrate (ε eff = 6) 10 made of alumina having a total length of 40 mm is 0.2 mm. On both sides of the strip-shaped signal line 20 formed of the metallization, a strip-shaped ground pattern 30 formed of a metallization having a width of 0.2 mm is provided between the inner edge of the ground pattern 30 and the side edge of the signal line 20 facing the ground pattern 30. They were arranged side by side in parallel with a distance of 0.2 mm. The ground pattern 30 includes a plurality of conductor vias formed by metallization, which are provided on the lower surface of the insulating substrate 10 in parallel with the ground pattern 30 and are arranged in a wide layer in a wide layer shape. Electrically connected via 40. And the signal line 20
Was considered as a microstrip line and its impedance was designed. Then, the characteristic impedance of the signal line 20 was matched with 50Ω.

FIG. 8 shows the ground pattern 3
0 is connected to the ground 50 through the plurality of conductor vias 40 that are vertically arranged side by side on the insulating substrate 10 at a pitch of 5 mm, and the stubs 60 are provided at both ends of the ground pattern 30. It shows the measured data of the transmission characteristics of the signal line 20 that does not have, ie, the length L of the stub 60 is zero. It can be seen that the lowest resonance frequency value of this signal line 20 is around 12 GHz.

On the other hand, in the structure shown in FIG. 9, the ground pattern 30 is used as the ground 50 and the insulating substrate 10 is 5 m long.
The signal line 20 is electrically connected through a plurality of conductor vias 40 arranged side by side vertically at m pitches, and the stubs 60 of 5 mm are provided at both ends of the ground pattern 30.
3 shows the actual measurement data of the transmission characteristic of the signal line 20 having In this signal line 20, the lowest resonance frequency value is 6
It turns out that it will fall to around GHz.

The signal line shown in FIG. 10 is a signal line in which the ground pattern 30 is electrically connected to the ground 50 through a plurality of conductor vias 40 which are arranged side by side vertically on the insulating substrate 10 at a pitch of 10 mm. 20 shows the measured data of the transmission characteristics of the signal line 20 having the stubs 60 at both ends of the ground pattern 30. It can be seen that the minimum resonance frequency value of the signal line 20 is around 6 GHz.

On the other hand, in the structure shown in FIG. 11, the ground pattern 30 is used as the ground 50 and the ground pattern 30 is used as the insulating substrate 10.
Transmission of the signal line 20 electrically connected through a plurality of conductor vias 40 arranged side by side vertically at a mm pitch, and having the 10 mm stubs 60 at both ends of the ground pattern 30 The actual measurement data of the characteristics are shown. It can be seen that in the signal line 20, the minimum resonance frequency value drops to around 3 GHz.

FIG. 12 shows the relationship between the minimum resonance frequency value of the signal line 20 and the length (sloping ground connection) L of the stub 60 in the wiring board shown in FIG. The relationship of the minimum resonance frequency value of the signal line 20 to the via pitch P of the plurality of conductor vias 40 provided is shown. According to this figure,
It can be seen that if the length L of the stub 60 is made short, the minimum resonance frequency value of the signal line 20 increases.

[0061]

As described above, according to the first wiring board of the present invention, the stub existing at the end portion of the ground pattern eliminates the adverse effect on the high frequency signal transmitted to the signal line, and the signal line is provided. A high frequency signal of 5 to 10 GHz or more can be efficiently transmitted with a small transmission loss. Or
By removing the stub from the end of the ground pattern, it is possible to efficiently transmit a high frequency signal of 5 to 10 GHz or higher to the signal line with little transmission loss.

According to the first wiring board of the present invention, since the end portion of the ground pattern is located inward of the end portion of the insulating substrate, when the ceramic green sheet for forming the insulating substrate is cut during the manufacturing thereof. In addition, it is possible to eliminate the need to simultaneously cut the metallized pattern for forming the ground pattern formed on the surface of the ceramic green sheet. Then, since the ceramic green sheet and the metallized pattern for forming the ground pattern are cut at the same time, it is possible to prevent a part of the metallized pattern from dripping on the cut surface of the ceramic green sheet.

According to the second wiring board of the present invention, the adverse effect of the stub existing at the end of the ground pattern on the high-frequency signal transmitted to the signal line is eliminated, and the signal line has 5 to 5 parts.
A high frequency signal of 10 GHz or higher can be efficiently transmitted with a small transmission loss.

According to the first or second wiring board of the present invention, in order to improve the high frequency characteristics of the signal line, a line or a half conductor via for electrically connecting the end of the ground pattern to the ground is provided. Since it is not necessary to provide the end face of the insulating substrate or the end portion of the insulating substrate, it is possible to easily manufacture a wiring substrate having a signal line having good high frequency characteristics without trouble.

[Brief description of drawings]

FIG. 1 is a partial perspective view of a first wiring board of the present invention.

FIG. 2 is a partial perspective view of a second wiring board of the present invention.

FIG. 3 is a partial perspective view of a first wiring board of the present invention.

FIG. 4 is a partial perspective view of a second wiring board of the present invention.

FIG. 5 is a partial side sectional view of the first wiring board of the present invention.

FIG. 6 is a partial side sectional view of a second wiring board of the present invention.

FIG. 7 is a plan view of a wiring board.

8 is a transmission characteristic data diagram of the wiring board of FIG.

9 is a transmission characteristic data diagram of the wiring board of FIG.

10 is a transmission characteristic data diagram of the wiring board of FIG.

FIG. 11 is a transmission characteristic data diagram of the wiring board of FIG. 7.

12 is a data diagram of the minimum resonance frequency value of the signal line of the wiring board of FIG.

FIG. 13 is a partial perspective view of a conventional wiring board.

FIG. 14 is a partial perspective view of a conventional wiring board.

FIG. 15 is a partial side sectional view of a conventional wiring board.

FIG. 16 is a partial perspective view of a conventional wiring board.

FIG. 17 is a partial perspective view of a conventional wiring board.

[Explanation of symbols]

 10 Insulating Substrate 20 Signal Line 30 Ground Pattern 30a Ground Pattern Part 30b Ground Pattern End 40 Conductor Via 50 Ground 60 Stub 70 Line 80 Half Conductor Via

Claims (6)

[Claims] 1. An end portion of the ground pattern in a wiring board in which a ground pattern provided on an insulating substrate side by side with a signal line is electrically connected to the ground through a plurality of conductor vias provided on the insulating substrate. Is located inward of the end of the insulating substrate, and the distance L between the end of the ground pattern and the ground pattern portion electrically connected to the conductor via closest to the end is defined as A high-frequency wiring board formed to be less than ¼ or zero of a wavelength λ of a high-frequency signal transmitted to a signal line. 2. A wiring board in which a ground pattern provided side by side with a signal line on an insulating substrate is electrically connected to the ground through a plurality of conductor vias provided on the insulating substrate, wherein In a wiring board having an end portion extended to the end portion of the insulating substrate, a distance L between the end portion of the ground pattern and a ground pattern portion electrically connected to the conductor via closest to the end portion is set to L. A wiring board for high frequency, which is formed to be less than ¼ of the wavelength λ of the high frequency signal transmitted to the signal line and larger than zero. 3. The ground pattern is a ground line for forming a signal line in a coplanar line.
Alternatively, the high frequency wiring board described in 2. 4. The ground pattern is a ground layer for forming a signal line in a pseudo rectangular coaxial line.
Alternatively, the high frequency wiring board described in 2. 5. The high frequency wiring board according to claim 1, wherein the ground pattern is a local ground plane for matching a characteristic impedance of a part of the signal line with a predetermined value. 6. The high frequency wiring board according to claim 1, wherein the ground is provided in a wide layered manner on the insulating substrate so as to face the signal line and the ground pattern.