JP2003218535A - Electric wiring board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric wiring board that can obtain a superior high-frequency transmission characteristic and EMI characteristic, by changing the dielectric constants of insulating layers surrounding wiring layers in accordance with the designs of wiring patterns. <P>SOLUTION: In this electric wiring board, insulating layers 5 and 7 are formed between adjacent wires in a wiring layer 4 formed on an insulating substrate, and an insulating layer 1 is formed between adjacent wiring layers of multiple wiring layers in the thickness direction. The dielectric constants of the insulating layers 5, 7, and 1 are made relatively higher or lower in accordance with the electrical roles of the signal line, power supply line, grounding line, etc., of each wiring. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a semiconductor chip or a semiconductor package having a high driving frequency, or a wireless LA.
N or Bluetooth-equipped analog high frequency device is mounted,
The present invention relates to a high frequency compatible electric wiring board capable of operating them at high speed.

[0002]

2. Description of the Related Art In the prior art, in order to cope with the miniaturization of semiconductor chips and semiconductor packages accompanying the speeding up of electrical signals, in the manufacture of semiconductor electrical wiring boards, high density and fine wiring is formed. A possible manufacturing process has been proposed. FIG. 10 shows a procedure of a semi-additive method which is a typical manufacturing process for explaining the conventional technique.

First, in FIG. 10A, an extremely thin underlying wiring layer 3 of about 1 μm is formed on a base material having a conductor layer 2 formed on one surface of an insulating layer 1 by electroless plating or sputtering.

In (b), a photosensitive resist layer 14 is formed on the upper part of the underlying wiring layer 3 by coating.

In (c) and (d), exposure and development are performed through a mask 15 for forming a wiring pattern prepared in advance, and the underlying wiring layer 3 is exposed at a portion where wiring is to be formed.

In (e) and (f), a conductor is deposited on the exposed underlying wiring layer 3 by the electrolytic plating method to form the wiring layer 4, and then only the resist layer 14 is completely removed by etching. To do.

In (g), the exposed portion of the underlying wiring layer 3 that short-circuits the wiring layer 4 is removed by soft etching to electrically isolate the respective wirings.

Next, in (h), the insulating layer 8 is formed so as to cover the wiring layer 4. In this case, as a forming method, a liquid insulating resin may be coated and then heated to crosslink and solidify, or a sheet-shaped insulating material may be laminated by heating and pressing. In the case of a multilayer wiring board, the above process is repeated for the required number of wiring layers to sequentially form the wiring layers 4 on the insulating layer 8.

Further, as a manufacturing process capable of forming fine wiring with high density, there is a subtractive method in addition to this, but the semi-additive method is suitable for producing high-definition wiring. Since the design rules of high-speed semiconductor chips and semiconductor packages have been miniaturized, the semi-additive method is mainly used as a method of manufacturing an electric wiring board for mounting the same.

However, in the conventional electric wiring board, when the wiring layers 4 are multi-layered, the insulating layer 8 between the wiring layers is coated with a liquid insulating resin and then heat-crosslinked and solidified, or a sheet-shaped insulating material. Since it was formed in a batch by the method of heating and laminating, the dielectric constant was constant in a single insulating layer.

When the frequency of the electric signal is low, the signal transmission characteristics can be secured even if the dielectric constant is constant regardless of the wiring pattern, and unnecessary electromagnetic radiation can be suppressed below the standard, but the frequency is in the gigahertz band. Then, it becomes necessary to change the dielectric constant according to the wiring pattern and secure the transmission characteristics and EMI characteristics.

The wiring layer 4 has a signal line as an electrical role,
It is roughly divided into a power line and a ground line, and it is better to change the dielectric constant of the insulating layer 8 depending on the combination of the respective arrangements.
Both transmission characteristics and EMI characteristics are improved. For example, the power supply line and the ground line that forms a closed loop in pair with the power supply line are often arranged close to each other, and in this case, the insulating layer 8 existing between the power supply line and the ground line.
The higher the dielectric constant, the better the electrical characteristics.

Regarding the insulating layer 8 existing between the signal line and the ground line or between the signal line and the power supply line, the characteristic impedance is lowered when the dielectric constant is high and the propagation delay is reduced when the dielectric constant is low. Therefore, a suitable dielectric constant in this case must be selected according to the function required of the electric wiring board at that time.

On the other hand, except for the case of transmitting a signal in the differential mode, the insulating layer existing between the two signal lines has a lower dielectric constant, which causes a delay between floating lines. The capacity can be reduced.

The above discussion applies not only to the positional relationship of the wirings in the in-plane direction within the same wiring layer 4, but also to the positional relationship of the vertical wirings in different wiring layers 4. Therefore, unless the dielectric constant of the insulating layer 8 surrounding the wiring layer 4 is changed according to the design of the wiring pattern, good electrical characteristics for a high frequency electric signal cannot be secured.

In the conventional electric wiring board, since the dielectric constant of the insulating layer 8 is constant regardless of the design of the wiring pattern, there is a big problem that good high frequency electric characteristics cannot be obtained.

[0017]

SUMMARY OF THE INVENTION An object of the present invention is to make it possible to change the dielectric constant of an insulating layer surrounding a wiring layer according to the design of a wiring pattern and to obtain good high frequency transmission characteristics and EMI characteristics. It is to provide an electric wiring board capable of

[0018]

The invention according to claim 1 of the present invention relates to an electric wiring board in which an insulating layer is formed between adjacent wirings in a wiring layer formed on an insulating layer base material. Electricity characterized in that the dielectric constant of the insulating layer is formed to have a relatively high dielectric constant or a relatively low dielectric constant according to the respective electrical roles of the signal line, the power supply line, the ground line, etc. of each wiring. It is a wiring board.

The invention according to claim 2 of the present invention relates to an electric wiring board in which an insulating layer is formed between wiring layers adjacent to each other in the board thickness direction in a multilayer wiring layer formed on an insulating layer base material. An electric wiring board characterized in that the dielectric constant of the insulating layer is formed to have a relatively high dielectric constant or a relatively low dielectric constant, respectively, according to the respective electrical roles of the signal line, the power supply line, and the ground line of the wiring. Is.

According to a third aspect of the present invention, an insulating layer is formed between wirings adjacent to each other in a wiring layer formed on an insulating layer base material, and a board in a multilayer wiring layer is formed. In an electric wiring board in which an insulating layer is formed between adjacent wiring layers in the thickness direction, a signal line of each wiring, a power supply line,
The electric wiring board is characterized in that the dielectric constant of the insulating layer is formed to have a relatively high dielectric constant or a relatively low dielectric constant depending on the electrical role of the ground line or the like.

[0021]

In the conventional electric wiring board, the dielectric constant in a single insulating layer is constant regardless of the electrical role of the wiring pattern. However, in the electric wiring board of the present invention, Not only in the positional relationship of the wiring in the in-plane direction but also in the positional relationship of the vertical wiring in different wiring layers, the dielectric constant of the insulating layer surrounding each wiring layer is changed according to the electrical role of the wiring pattern. .

[0022]

The present invention will be described in detail based on the illustrated embodiment.

2 and 3 show a basic manufacturing process of the electric wiring board according to the present invention, and FIG.
Since (h) is the same as the conventional semi-additive method, its explanation is omitted here.

2 (a) to 2 (g), a base wiring layer 3 and a wiring layer 4 are sequentially formed on an insulating layer 1 of a base material having a conductor layer 2 formed on one surface of the insulating layer 1. There is.

The wiring layer 4 of FIG. 2 (h) has a power supply wiring 4v, a ground wiring 4g, and a signal wiring 4s because of its electrical role.
It is composed of a and 4sb. The high dielectric constant insulating layer 5 is formed on the wiring layer 4 of such a wiring structure. As a forming method, a liquid insulating resin is coated, or a sheet-like insulating resin is laminated by heating and pressurizing to cover the upper portion of the wiring layer 4. The high dielectric constant insulating layer 5 covering the upper portion of the wiring layer 4 is polished or etched until the conductor layer 4 is exposed.

A description will be given with reference to FIGS. 3 (i) to 3 (l).

In FIG. 3I, only a predetermined portion of the high dielectric constant insulating layer 5 existing between the wiring layers 4 is removed by etching. The high dielectric constant insulating layer 5 to be removed is the two signal lines 4 that do not transmit signals in the differential mode.
It is a portion existing between sa and the signal line 4sb.

If a signal is transmitted in the differential mode even between signal lines, the high dielectric constant insulating layer 5 is not a target for removal. When the power supply lines or the ground lines are arranged adjacent to each other, the high dielectric constant insulating layer 5 existing between them is removed. Normally, power lines are
Or 2 if the ground lines are adjacent to each other
Since most of the wires of a book are integrated into one wide wire, there are not many such designs. In an electric wiring board having multiple power supplies and ground systems, if the power supply lines with different power supplies and ground systems or the ground lines are adjacent to each other, it is necessary to separate them securely so that there is no electromagnetic coupling between them. So
The high dielectric constant insulating layer 5 must be removed. Also,
The high dielectric constant insulating layer 5 between the signal line and the power line or between the signal line and the ground line is left as it is when the characteristic impedance is desired to be reduced, but is removed when the propagation delay is desired to be reduced. That is, whether or not to remove the high dielectric constant insulating layer 5 is determined according to the specifications of the electric wiring board at that time.

A protective film 6 is formed on a portion of the high-dielectric-constant insulating layer 5 left unetched to prevent it from being etched. Since the protective film 6 does not have a problem even if it partially covers the upper portion of the wiring layer 4, it is not necessary to form a film with strict dimensional accuracy.

In FIG. 3 (j), the high dielectric constant insulating layer 5 is removed by etching.

In FIG. 3K, after the high dielectric constant insulating layer 5 is left only between the predetermined wirings in this manner, the low dielectric constant insulating layer 7 is formed on the wiring layer 4. As a forming method, a liquid insulating resin is coated, or a sheet-like insulating resin is laminated by heating and pressurizing to cover the upper portion of the wiring layer 4. The values of the dielectric constants of the high-dielectric-constant insulating layer 5 and the low-dielectric-constant insulating layer 7 do not define absolute values, but indicate that a relative magnitude relationship is established.

In FIG. 3 (l), by repeating the above process, the wiring layers are multilayered to form a multilayer electric wiring board.

In the electric wiring board having such a structure,
In the wiring layer 4, depending on the arrangement of the signal line, the power line, and the ground line, it is possible to select whether the insulating layer existing between the lines has a high dielectric constant or a low dielectric constant.

FIG. 4 is a cross section of the electric characteristic evaluation substrate 1 in which two wirings L1 and L2 are taken out from the basic structure of the present invention. The thickness of the insulating layer 1 is 20 μm, the wirings L1 and L2,
Width is 10 μm, its thickness is 8 μm, space between lines is 1
The thickness of the insulating layer 7 is 0 μm, and the thickness of the insulating layer 7 is 28 μm. Wiring L
Cu materials 1 and L2 are used, and the relative dielectric constants of the insulating layers 1 and 7 are 2.0. When the relative dielectric constant of the insulating layer 8 between the wirings L1 and L2 is set to 2.0 or 4.0, S-parameters regarding crosstalk between lines are S31 and S.
41 is as shown in FIG.

At this time, the input side of the wiring L1 is the port 1,
The output side is port 2, the input side of the wiring L2 is port 3, and the output side is port 4. From this result, it can be seen that the lower the relative permittivity of the insulating layer 8, the smaller the crosstalk.
Therefore, if the wirings L1 and L2 are signal lines that do not transmit in the differential mode, the lower the dielectric constant of the insulating layer 8, the better the transmission characteristics.

On the contrary, in the case of the signal line transmitted in the differential mode, the characteristics are improved by increasing the dielectric constant in order to strengthen the coupling between the lines. For example, the thickness of the insulating layer 1 is 20 μm, the width of the wirings L1 and L2 is 20 μm, the thickness thereof is 8 μm, the space between lines is 20 μm, and the thickness of the insulating layer 7 is 28 μm. The wirings L1 and L2 are made of Cu material, and the relative dielectric constants of the insulating layer 1 and the insulating layer 7 are 2.0. The capacitance per unit length at this time is 34 pF / m when the dielectric constant of the insulating layer 8 is 2.0, and the dielectric constant is 4.0.
In case of, it becomes 41 pF / m. Similarly, the wirings L1 and L2
Even when is a pair of a power supply line and a ground line forming a closed loop, the larger the capacitance is, the more stable the power supply and the ground potential are. Therefore, the insulating layer 8 having the larger relative dielectric constant has the better electric characteristics.

When the wirings L1 and L2 are a combination of a signal line and a power line or a combination of a signal line and a ground line, if the insulating layer 8 has a high dielectric constant, the characteristic impedance is reduced, and if it is a low dielectric constant, the propagation delay occurs. Therefore, the dielectric constant of the insulating layer 8 is selected to be large or small depending on which is more important in the specifications of the electric wiring board.

For example, FIG. 5 is a cross section of the electrical characteristic evaluation substrate 2 in the form of a coplanar microstrip line.

The insulating layer 1 has a thickness of 20 μm and the wirings G1 and G
2. The width of S1 is 20 μm, the thickness thereof is 8 μm, the space between lines is 20 μm, and the thickness of the insulating layer 7 is 28 μm. The wirings G1, G2 and S1 are made of Cu material, and the relative dielectric constants of the insulating layers 1 and 7 are 2.0. Ground line G
When the relative dielectric constant of the insulating layer 8 between the signal line S1 and the signal line S1 is 2.0 and 4.0, the capacitance per unit length is 55 pF / m and 70 pF / m, respectively. Since the capacitance can be changed by changing the relative permittivity of the insulating layer 8, it is possible to obtain electric characteristics that match the specifications of the electric wiring board.

Further, in FIG. 4, when the wirings L1 and L2 are power supply lines or ground lines, especially when the power supply and the ground system are different from each other, the relative dielectric constant of the insulating layer 8 is lowered to reduce electromagnetic waves. The decoupling reduces unwanted electromagnetic radiation and improves electrical properties.

As described above, depending on whether the wiring is a signal line, a power supply line, or a ground line, the magnitude relationship of the dielectric constant required for the insulating layer between the lines to improve the electrical characteristics differs.
Therefore, the ability to dispose an insulating layer having a large or small permittivity between arbitrary lines is extremely advantageous when transmitting a high-frequency signal having severe electrical characteristics.

Next, the second manufacturing process in which the order of forming the high dielectric constant insulating layer 5 and the low dielectric constant insulating layer 7 in the basic manufacturing process shown in FIGS.
It shows in (f).

In FIG. 6A, the conductor layer 2 is formed on one surface of the insulating layer 1.
A base wiring layer 3 and a wiring layer 4 are sequentially formed on the insulating layer 1 of the base material on which is formed. The wiring layer 4 is composed of a power supply wiring 4v, a ground wiring 4g, and signal wirings 4sa and 4sb because of its electrical role.

In FIG. 6B, a low dielectric constant insulating layer 7 is formed on the wiring layer 4 of such a wiring structure. As a forming method, a liquid insulating resin is coated, or a sheet-shaped insulating resin is laminated under heating and pressure to cover the upper portion of the wiring layer 4. The low dielectric constant insulating layer 8 covering the upper portion of the wiring layer 4 is polished or etched until the conductor layer 4 is exposed.

Next, as shown in FIG. 6C, of the low dielectric constant insulating layer 7 existing between the wiring layers 4, only a predetermined portion is removed by etching. The low dielectric constant insulating layer 7 to be removed is
It is a portion existing between the power supply line 4v and the ground line 4g. The low dielectric constant insulating layer 7 between the signal line and the power supply line or between the signal line and the ground line is left as it is when the propagation delay is desired to be reduced, but is removed when the characteristic impedance is desired to be reduced. That is, whether or not to remove the low dielectric constant insulating layer 7 is determined according to the specifications of the electric wiring board at that time. In the embodiment of FIG. 6, the signal line 4s
low dielectric constant insulating layer 7 existing between a and the ground line 4g
Are removed by etching in order to give priority to the reduction of the characteristic impedance. A protective film 6 is formed on the portion of the low dielectric constant insulating layer 7 that remains without being etched to prevent it from being etched.

In FIG. 6D, the low dielectric constant insulating layer 7 was removed by etching.

In FIG. 6E, after the low dielectric constant insulating layer 7 is left only between the predetermined wirings in this manner, the high dielectric constant insulating layer 9 is formed on the wiring layer 4. As a forming method, a liquid insulating resin is coated or a sheet-shaped insulating resin is heat-laminated to cover the upper portion of the wiring layer 4.

In FIG. 6F, by repeating the above process, the wiring layers are multilayered to form a multilayer electric wiring board.

In the basic manufacturing process shown in FIGS. 2 and 3, for example, as shown in FIG. 3K, the low dielectric constant insulating layer 7 is always present on the wiring layer 4. In this case,
Since the insulating layer between the wiring layer 4 and the upper wiring layer 10 has a low dielectric constant, when the wiring layer 4 and the upper wiring layer 10 are mainly composed of signal lines, the inter-line capacitance between the layers is reduced. Will be reduced.
As a result, there is an advantage that the propagation delay can be reduced.

On the other hand, in the layer structure by the manufacturing process shown in FIG. 6, for example, as shown in FIG. 6E, the high dielectric constant insulating layer 9 is always present on the wiring layer 4. In this case, since the insulating layer between the wiring layer 4 and the upper wiring layer 10 has a high dielectric constant, the wiring layer 4 and the upper wiring layer 10 are mainly composed of a power line and a ground line that form a pair. If so, the line capacitance between layers can be increased. As a result, there is an advantage that fluctuations in the potential of the power supply and the ground can be reduced when the semiconductor devices are simultaneously switched. For this reason, an appropriate process can be selected from the basic manufacturing process of FIGS. 2 and 3 and the manufacturing process of FIG. 6 depending on the roles mainly played by the wiring layer 4 and the upper wiring layer 10. it can.

In the manufacturing process described so far, the dielectric constant of the insulating layer between adjacent wirings can be selected within the same wiring layer. Here, a third manufacturing process in which the dielectric constants of the insulating layers between the wiring layers adjacent to each other above and below the electric wiring board can be selected will be described with reference to FIGS.

In FIG. 7A, the conductor layer 2 is formed on one surface of the insulating layer 1.
A base wiring layer 3 and a wiring layer 4 are sequentially formed on the insulating layer 1 of the base material on which is formed. The wiring layer 4 is composed of a power supply wiring 4v, a ground wiring 4g, and signal wirings 4sa and 4sb due to its electrical role. A high dielectric constant insulating layer 5 is formed between the power supply wiring 4v and the ground wiring 4g, and between the ground wiring 4g and the signal wiring 4sa. A low dielectric constant insulating layer 7 is formed on the wiring layer 4 of such a wiring structure. The above configuration can be created by the basic manufacturing process. Further, the protective layer 11 is formed at a predetermined position on the surface of the low dielectric constant insulating layer 7.

Next, as shown in FIG. 7B, a predetermined portion of the low dielectric constant insulating layer 7 covering the upper portion of the wiring layer 4 is etched until the conductor layer 4 is exposed. Low dielectric constant insulating layer 7 to be removed
In the wiring layer 4 and the upper wiring layer 10 are determined according to the roles of the wirings vertically adjacent to each other in the thickness direction. Two signal lines 4s that do not transmit signals in differential mode
The low dielectric constant insulating layer 7 existing between a and 10 sa and 4 sb and 10 sb is left without being removed by etching. When the signal is transmitted in the differential mode even between the signal lines, the low dielectric constant insulating layer 7 is removed. On the other hand, the low-dielectric-constant insulating layer 7 existing between the power line 4v and the ground line 10g and the ground line 4g and the power line 10v forming a pair is removed by etching. Further, when the power supply lines or the ground lines are arranged vertically, the low dielectric constant insulating layer 7 existing between them is not removed. Further, when the signal line and the power line or the signal line and the ground line are vertically adjacent to each other, the low dielectric constant insulating layer 7 between the lines is left as it is when the propagation delay is desired to be reduced, but the characteristic impedance is reduced. Remove if you want to. That is, whether or not to remove the low dielectric constant insulating layer 7 is determined according to the specifications of the electric wiring board at that time. A protective film 11 is formed on the remaining portion of the low dielectric constant insulating layer 7 without being etched to prevent it from being etched.

In FIG. 7C, the low dielectric constant insulating layer 7 is removed by etching. Next, the protective film 11 was removed by thin film processing.

In FIG. 7D, after the low dielectric constant insulating layer 7 is left only between the predetermined wiring layers in this way, the high dielectric constant insulating layer 12 is formed on the wiring layer 4. As a forming method, a liquid insulating resin is coated or a sheet-shaped insulating resin is heat-laminated to cover the upper portion of the wiring layer 4. Polishing and etching are performed until the low dielectric constant insulating layer 7 is exposed.

In FIG. 7E, the upper wiring layer 10 is formed by an ordinary semi-additive process. By repeating the above process, the wiring layers are multilayered to form a multilayer electric wiring board.

In the case of the above structure, the dielectric constant of the insulating layer existing between the adjacent wirings can be selected not only in the same wiring layer but also in different wiring layers.

For example, it becomes possible to prepare the electric characteristic evaluation substrate 3 as shown in FIG. Next, referring to FIG. 8, the insulating layer 13 between the wiring Lb and the upper wiring layer Lu 1 is formed.
The line-to-line capacities when the dielectric constants of the above are set to 2.0 and 4.0 are 54 pF / m and 89 pF / m per unit length, respectively.
Becomes However, the thickness of the insulating layer 1 is 20 μm, the wirings Lb, L
The width of u is 40 μm, the thickness thereof is 8 μm, and the thickness of the low dielectric constant insulating layer 7 is 28 μm. The wirings Lb and Lu are made of a Cu material, and the dielectric constants of the insulating layers 1 and 7 are 2.0. Wiring L
If both b and Lu are signal lines that do not transmit in the differential mode, the capacitance is reduced and the crosstalk and the propagation delay are reduced by lowering the dielectric constant. On the other hand, when the wirings Lb and Lu are the power supply line and the ground line that form a pair, the higher the dielectric constant, the larger the capacitance and the more stable the potentials of the power supply and the ground.

[0059]

As described above, the electric wiring board according to the present invention includes the signal lines of the wirings formed in the same wiring layer,
The dielectric constant of the insulating layer existing between the adjacent wirings can be changed according to the electrical role such as the power supply line and the ground line. Also, depending on the electrical role of the signal lines, power supply lines, ground lines, etc. of the wiring formed in the wiring layers that are vertically adjacent to each other in the thickness direction of the electric wiring board, the dielectric properties of the insulating layers existing between the upper and lower wiring layers You can also change the rate. Thus, depending on the electrical role of the wiring,
Since the relative magnitude of the dielectric constant of the insulating layer that exists between wires can be set arbitrarily, propagation delay, crosstalk, etc. when transmitting high-frequency signals can be reduced, and fluctuations in the potential of power supply and ground. Can be suppressed. It is possible to provide an electric wiring board that can obtain good high-frequency transmission characteristics and EMI characteristics. Further, as a result, distortion and reflection of the waveform of the high-frequency electric signal can be suppressed, a signal having a favorable waveform can be transmitted, and unnecessary electromagnetic radiation can be reduced.

[Brief description of drawings]

FIG. 1 is a side sectional view showing a structure of an example of an electric wiring board according to the present invention.

2A to 2H are side sectional views for explaining the manufacturing process of the present invention.

3 (i) to (l) are side sectional views for explaining the manufacturing process of the present invention.

FIG. 4 is a side sectional view showing the structure of the electrical characteristic evaluation substrate 1.

FIG. 5 is a side sectional view showing the structure of the electrical characteristic evaluation substrate 2.

FIG. 6 is a process side sectional view illustrating a second manufacturing process of the present invention.

FIG. 7 is a process side sectional view illustrating a third manufacturing process of the present invention.

FIG. 8 is a side sectional view showing the structure of the electrical characteristic evaluation substrate 3 of the third manufacturing process of the present invention.

FIG. 9 is a crosstalk characteristic graph of the electric characteristic evaluation substrate 1.

10A to 10H are side sectional views for explaining a manufacturing process of a conventional semi-additive method.

[Explanation of symbols]

1 ... Insulation layer 2 ... Conductor layer 3 ... Base wiring layer 4 ... Wiring layer 4v ... power line 4g ... ground wire 4sa ... Signal line 4sb ... Signal line 5 ... High dielectric constant insulating layer 6 ... Protective film 7 ... Low dielectric constant insulating layer 8 ... Insulating layer 9 ... High dielectric constant insulating layer 10 ... Upper wiring layer 10v ... power line 10g ... ground wire 10sa ... Signal line 10sb ... Signal line 11 ... Protective film 12 ... High dielectric constant insulating layer 13 ... Insulating layer 14 ... Resist layer 15 ... Mask L1 ... Wiring L2 ... Wiring G1 ... Ground line G2 ... Ground line S1 ... Signal line Lb ... Wiring Lu ... Wiring

Claims (3)

[Claims] 1. An electric wiring board in which an insulating layer is formed between adjacent wirings of a wiring layer formed on an insulating layer base material. The electric wiring board is characterized in that the dielectric constants of the insulating layers are formed to have a relatively high dielectric constant or a relatively low dielectric constant, respectively, depending on their respective roles. 2. An electric wiring board in which an insulating layer is formed between wiring layers adjacent to each other in the board thickness direction in a multi-layer wiring layer formed on an insulating layer base material, in which a signal line, a power supply line of each wiring,
An electric wiring board, characterized in that the dielectric constant of the insulating layer is formed to have a relatively high dielectric constant or a relatively low dielectric constant depending on the electrical role of each ground line. 3. An insulating layer is formed between wirings adjacent to each other on a wiring layer formed on an insulating layer base material, and between the wiring layers adjacent to each other in the board thickness direction of the formed multilayer wiring layers. In an electric wiring board on which an insulating layer is formed, the dielectric constant of the insulating layer is set to a relatively high dielectric constant or a low dielectric constant depending on the electrical roles of the signal line, the power supply line, the ground line, etc. of each wiring. An electric wiring board having a dielectric constant.