JPH0513961A - Multilayer wiring board - Google Patents

Abstract

PURPOSE:To prevent a multilayer wiring board from generating power supply noises to a semiconductor device or the like even if the board is not mounted with an additional capacitor component and to enable the multilayer wiring board to be enhanced in both wiring density and component mounting density and lessened in number of components. CONSTITUTION:A circular or polygonal hole having a diameter of 2r1 is bored in an insulating layer 7 whose permittivity is epsilon1 penetrating through it, a dielectric body layer 8 of a permittivity of epsilon2 is provided fitting in the hole concerned and fixed with hardening dielectric resin or the like, where epsilon is so set as to satisfy a formula, epsilon<epsilon. As mentioned above, a power supply conductor layer (conductor pattern) is formed on both the sides of an integral structure where the dielectric layer 8 and the insulating layer 7 are formed into one piece. By this setup, a capacitor part whose capacitance C is as large as epsilon2epsilon0 (pir1<2>/d1) is formed, so that a multilayer wiring board of this design is adequate to be used as a multilayer wiring board provided with a power supply noise preventing function.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multilayer wiring board, and more particularly to a multilayer wiring board having a capacitor function for preventing power source noise.

[0002]

2. Description of the Related Art In recent years, it has been generally known to use a capacitor as a means for absorbing noise from a power source in a mounted circuit device in which a semiconductor device such as an IC element is mounted on a wiring board. 3 and 4 are perspective views showing mounting examples of the power supply noise prevention capacitor. In these figures, 1 is a multilayer in which conductor pattern layers (conductor layers) and insulating layers are alternately laminated. The wiring board 2 is a semiconductor device such as an IC package mounted and mounted on one main surface thereof. And, in the vicinity of the mounted semiconductor device 2 of the multilayer wiring board 1,
A capacitor 3 component for preventing power supply noise is mounted, and lead wires 4a and 4b of the capacitor 3 are connected to power supply conductor layers 5 and 6 having different potentials which are arranged in inner layers of the multilayer wiring board 1, respectively. ing.

[0003]

However, in the power supply noise prevention structure having the above-mentioned structure, by mounting the power supply noise prevention capacitor 3, a region and a wiring pattern in which electronic parts can be mounted and mounted on the surface of the multilayer wiring board 1 There is a problem that the area where the (conductor layer) can be formed is regulated, which impairs high-density mounting or downsizing of a mounted circuit device. That is, when attempting to achieve high-density mounting or downsizing of a mounted circuit device, conversely, not only the mounting / arrangement area of the power supply noise prevention capacitor 3 is significantly restricted, but also the power supply conductor layer 5 having different potentials. , 6 is inevitably complicated and complicated.

The present invention has been made in order to solve such a problem, and it is possible to realize high density wiring, high density mounting of electronic parts, and reduction of the number of electronic parts, and therefore a mounting circuit. It is an object of the present invention to provide a multilayer wiring board that can be downsized.

[0005]

A multi-layer wiring board according to the present invention is a multi-layer wiring board in which conductor layers are laminated with an insulating layer interposed between adjacent conductor layers having different potentials.
A predetermined region of an insulating layer between two power supply conductor layers is selectively configured by a dielectric having a dielectric constant higher than that of the insulating layer, and a portion functioning as a capacitor is formed between the two power supply conductor layers. It is characterized by

[0006]

In the above-mentioned multilayer wiring board, a predetermined region of the insulating layer between the power supply conductors (patterns) having different potentials is selectively replaced with a dielectric having a dielectric constant higher than the dielectric constant. Is made. Then, the selectively replaced dielectric region forms a portion having a function as a capacitor between the two power supply conductor pattern layers, and thus effectively functions to prevent noise from the power supply. .. Therefore, it is not necessary to specifically mount and mount a power supply noise preventing capacitor on the main surface of the multilayer wiring board, and it is possible to effectively utilize the surface of the wiring board and achieve high density of electronic components and wiring.

[0007]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a cross-sectional view showing an example of the essential structure of a multilayer wiring board according to the present invention. A part of an insulating layer 7 interposed between power supply conductor layers 5 and 6 forming an inner layer (predetermined). Area)
A dielectric 8 having a dielectric constant higher than that of the insulating layer 7
It is configured by replacing (embedding) with. That is,
In the multilayer wiring board according to the present invention, a part of the inner insulating layer 7 having a thickness of d _{1 and made of} an insulating material having a dielectric constant ε ₁ interposed between the power supply conductor layers 5 and 6 is used. It is the essence of the configuration that it is replaced with 8 of a dielectric having a dielectric constant ε ₂ much larger than the dielectric constant ε _{1 of} .

The multilayer wiring board having such a structure can be easily manufactured and constructed as follows. That is, the first power supply conductor layer (pattern) is formed on the surface of the supporting substrate.
After forming 5, the insulating layer 7 having a dielectric constant ε ₁ is formed on the surface of the first power supply conductor layer (pattern) 5. Next, a circular or polygonal hole having a diameter 2r ₁ reaching the surface of the first power supply conductor layer (pattern) 5 is made in a predetermined region of the formed insulating layer 7, and a dielectric material having a dielectric constant ε ₂ is formed in this hole. 8
Insert and fill, and fix with a dielectric curable resin. After that, a second power supply conductor layer (pattern) 6 is deposited on the surface where the dielectric layer 8 and the insulating layer 7 are integrated. In this structure, after the dielectric layer 8 and the insulating layer 7 are integrated, copper foils are laminated on both surfaces of the dielectric layer 8 and the insulating layer 7 with a dielectric curable resin, and a so-called photo-etching process is performed to supply power. Conductor pattern 5, 6
May be formed.

After forming the required power supply noise preventing capacitor functional area as described above, if necessary, further insulating layer,
A required multilayer wiring board can be obtained by sequentially forming the conductor layers (pattern layers) in a laminated manner by a conventional method.

In the multilayer wiring board thus formed, two power supply pattern layers 5 and 6 and, for example, a columnar dielectric layer 8 sandwiched or arranged between the power supply pattern layers 5 and 6 are provided. From (diameter 2r ₁ , dielectric constant ε ₂ ), the capacitance C = ε ₂ ε ₀ (πr ₁ ² / d ₁ ) (where ε
₀ is the vacuum permittivity and π is the circular constant. ) Is formed. And actually the thickness 0.5mm prepreg insulating layer 7 (dielectric constant epsilon ₁ 48), the dielectric constant epsilon ₂ as dielectric
In the case where a ceramic columnar body having a diameter of 10.0 mm is embedded and arranged in the prepreg using 1200 ceramics, a capacitor having a capacitance of 0.01 μF was formed.

A multilayer wiring board can be obtained by laminating outer layer copper foils on both surfaces of the inner layer power supply section thus configured through prepregs. In the multilayer wiring board, the inner layer section serves as a capacitor. Since the portion having the function is built in, a stable electric signal without noise can be supplied to the semiconductor device without separately mounting a capacitor component. Therefore, the area of the area where wiring is possible on the wiring board is increased, and the wiring density can be increased.
Further, since the number of parts is also reduced, the degree of integration of other parts can be increased as compared with the conventional one.

Next, another embodiment of the present invention will be described with reference to FIG. FIG. 2 is a perspective view showing an example of the essential structure, in which 9 is an insulating layer made of an insulating material having a permittivity ε ₃ and having a thickness of d ₂ , and 10 and 11 are attached to both surfaces of the insulating layer 9, respectively. It is a power supply conductor layer arranged. Here, the power supply conductor layer
Both 10 and 11 are made of copper foil, and one power supply conductor layer 10 is provided with slit-shaped notches 12 in a certain direction at a predetermined interval r ₂ . Further, the other power supply conductor layer 11 is provided with slit-shaped notches 12 so as to be orthogonal to the notches 12 at the same interval r ₂ .

In this structure, the insulating layer 9 (thickness d ₂ , dielectric constant ε ₃ ) is sandwiched by the power supply conductor layers 10 and 11 made of copper foil from both upper and lower sides (power supply conductor layer). (Interposed between 10 and 11) is the capacitance C = ε
_It has a function as a capacitor having ₃ ε ₀ (r ₂ ² / d ₂ ).

Therefore, in the multilayer wiring board obtained by laminating the outer layer copper foils on the surfaces of the inner layer power supply conductor layers 10 and 11 via the prepregs respectively, the wiring density can be increased and the number of parts can be reduced. .. Further, as compared with the multilayer wiring board of the above-described embodiment, it is possible to save the labor of separately disposing and inserting another dielectric in the insulating layer 9 and to facilitate the manufacturing, and to use the dielectric having a smaller dielectric constant. Therefore, there is an advantage that the effect of preventing power source noise can be achieved.

[0016]

As described above, according to the multilayer wiring board of the present invention, the capacitor component for preventing power source noise can be removed from the mounting surface of a semiconductor device or the like. Therefore, it is possible to realize high density wiring and reduce the number of parts. In addition to being able to mount other parts in the area where capacitor parts were conventionally mounted,
The substrate size can be made smaller.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a configuration example of a main part of a multilayer wiring board according to the present invention.

FIG. 2 is a perspective view showing another configuration example of the main part of the present invention.

FIG. 3 is a perspective view showing a configuration of a conventional mounted circuit device provided with a power supply noise prevention capacitor.

FIG. 4 is a partial cross-sectional view showing a configuration of a conventional mounted circuit device provided with a power supply noise prevention capacitor.

[Explanation of symbols]

1 ... Multilayer wiring board 2 ... Semiconductor device 3 ... Capacitor
4a, 4b ... Capacitor lead wires 5, 6, 10, 11
... Power supply conductor layers 7, 9 ... Insulating layer 8 ... Dielectric layer
12 ... Notch

Claims (1)

Claim: What is claimed is: 1. In a multilayer wiring board in which conductor layers are laminated with an insulating layer interposed therebetween, a predetermined insulating layer between two adjacent power supply conductor layers having different potentials in the conductor layers. A multilayer wiring board characterized in that a region is selectively constituted by a dielectric having a dielectric constant higher than that of the insulating layer, and a portion functioning as a capacitor is formed between two power supply conductor layers.