JPH11284344A - Ceramic multi-layer wiring board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a ceramic multi-layer board with normal and stable operation in a semiconductor integrated element mounted thereon, by reducing a variation in electric resistance of a signal metallized wiring conductor. SOLUTION: In an insulating board 1 made up of a plurality of ceramic insulating layers 1a to 1e, a signal metallized wiring conductor 4 and power metallized wiring conductors 2 and 3 are provided between each insulating layer 1a to 1e. The signal metallized wiring conductor 4 has electric resistivity larger than that of the power metallized wiring conductors 2 and 3 and has a thickness larger than that of the power metallized wiring conductors 2 and 3. In this case, a variation in electric resistivity of the signal metallized wiring conductor 4 is made small, and an erroneous operation or a break in the semiconductor integrated circuit element can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ceramic multilayer wiring board for mounting electronic components such as semiconductor elements.

[0002]

2. Description of the Related Art Conventionally, a ceramic multilayer wiring board for mounting a semiconductor integrated circuit element has an insulating base formed by vertically stacking and integrating a plurality of insulating layers made of an electrically insulating material such as an aluminum oxide sintered body. A metallized wiring conductor for power supply for supplying power to the semiconductor integrated circuit element and a metallized wiring conductor for signal for inputting / outputting a signal to / from the semiconductor integrated circuit element are arranged between the respective insulating layers.

In each insulating layer forming the insulating base, a large number of power supply via conductors and signal via conductors are provided from the power supply metallized wiring conductors and signal metallized wiring conductors to the surface of the insulating base through the respective insulating layers. The power supply via conductor and the signal via conductor allow the power supply metallized wiring conductor and the signal metallized wiring conductor to be electrically led to the surface of the insulating base.

In such a ceramic multilayer wiring board, the metallized wiring conductor for power supply for supplying power to the semiconductor integrated circuit element preferably has a lower electric resistance. Further, the metallized wiring conductor for signal does not require a very low electric resistance value, but it is preferable that the dispersion of the electric resistance value is small.

In such a ceramic multilayer wiring board, a metallized wiring conductor for power supply for supplying power to the semiconductor integrated circuit element has been recently developed with the ultra-high integration and ultra-high speed of the semiconductor integrated circuit element. And metallized wiring conductors for signals for taking signals in and out of the semiconductor integrated circuit element are being provided separately between insulating layers different from each other, and metallized wiring conductors for power supply are provided over almost the entire surface between certain insulating layers. A metallized wiring conductor for signal is provided as a wide area pattern, and a large number of elongated patterns having a width of about 100 μm are provided between certain insulating layers.

By supplying power to the semiconductor integrated circuit element from such a large-area metallized wiring conductor for power supply, stable power supply becomes possible, and the metallized wiring conductor for power supply serves as an electromagnetic shield, and a signal Unnecessary noise is prevented from entering the metallized wiring conductor for signal from the outside, or unnecessary electromagnetic radiation is prevented from being emitted from the metallized wiring conductor for signal to the outside.

As described above, if each insulating layer is a ceramic multilayer wiring board made of an aluminum oxide sintered body, a metallized wiring conductor for power supply, a metallized wiring conductor for signal, a via conductor for power supply and a via conductor for signal are provided. Metallized high melting point metal powders such as tungsten and molybdenum are used.

The metallized metal powder of high melting point metal such as tungsten or molybdenum generally has an electric resistivity of about 10 μΩ.
・ It is about cm.

[0009] The thickness of the metallized high melting point metal powder is usually set to about 10 µm. this is,
If the thickness of the refractory metal powder metallization is, for example, 20 μm or more, especially in a large-area pattern such as a metallized wiring conductor for a power supply, a lamination failure occurs between the upper and lower insulating layers sandwiching the refractory metal powder metallization. This is because it easily occurs.

If the electrical resistivity of the metal powder of the high melting point metal such as tungsten or molybdenum is 10 μΩ · cm as described above, if the thickness of the metallization of the high melting point metal powder is 10 μm, Has a sheet resistance of 10 mΩ.

Therefore, in such a ceramic multilayer wiring board using a metal powder of a refractory metal such as tungsten or molybdenum as the metallization wiring conductor for power supply and the metallization wiring conductor for signal, for example, when designing the ceramic multilayer wiring board, The thickness of the power metallization wiring conductor and signal metallization wiring conductor is, for example, 10 μm.
The sheet resistance of the metallized wiring conductor for power supply and the metallized wiring conductor for signal at that time is designed to be 10 mΩ.

In this ceramic multilayer wiring board, ceramic green sheets to be used as insulating layers are prepared, and via holes (through holes) for providing power supply via conductors and signal via conductors are formed in these ceramic green sheets. Thereafter, the via holes are filled with a metal paste to be a power supply via conductor and a signal via conductor by using a screen printing method, and metallized wiring conductors for power supply and metalized wiring for signal are provided on the upper and lower surfaces of each ceramic green sheet. The metal paste to be the conductor is printed and applied in a predetermined pattern by using the screen printing method,
Finally, these ceramic green sheets are laminated in a predetermined order and fired at a high temperature.

[0013]

However, in this conventional ceramic multilayer wiring board, a metal paste to be a metallized wiring conductor for power supply or a metallized wiring conductor for signal is printed on a ceramic green sheet to be an insulating layer by a screen printing method. In this case, a thickness variation of about 2 to 4 μm occurs in the thickness of the printed metal paste. Such a thickness variation gives a variation in the electric resistance value of the metallized wiring conductor for power supply and the metallized wiring conductor for signal.

The variation in the electric resistance value due to the variation in the thickness is such that the thickness of the metallized wiring conductor for the power supply and the metallized wiring conductor for the signal is set to, for example,
In the case where the metallized wiring conductor for power supply and the metalized wiring conductor for signal are used, the electrical resistance value is about ± 20% of the designed value.

The variation in the electric resistance value is as small as several mΩ at most in a metallized wiring conductor for power supply formed by a wide area pattern over substantially the entire surface between the insulating layers, but the pattern width is 100 μm. In a metallized wiring conductor for a signal that is as thin as possible, the variation in electric resistance value is as large as several hundred mΩ to several Ω.

Such a large variation in the electric resistance value of the signal metallized wiring conductor affects the operation of the semiconductor integrated circuit element mounted on the ceramic multilayer wiring board.
This may cause malfunction or inoperability of the semiconductor integrated circuit device. In other words, if the electrical resistance of the metallized wiring conductor for signal becomes significantly higher than the design value, there is a danger that the signal propagating through the metallized wiring conductor for signal will be greatly attenuated and the semiconductor integrated circuit element will not operate normally. If the electrical resistance of the signal metallized wiring conductor becomes significantly lower than the designed value, spike noise generated in the signal propagating through the signal metallized wiring conductor cannot be attenuated properly. In addition, there is a greater danger of causing a malfunction in the semiconductor integrated circuit device.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to reduce the variation in the electrical resistance of signal metallized wiring conductors so that a semiconductor integrated circuit element to be mounted can be normally and stably mounted. An object of the present invention is to provide a ceramic multilayer wiring board that can be operated.

[0018]

According to the ceramic multilayer wiring board of the present invention, a metallized wiring conductor for signal and a metallized wiring conductor for power supply are provided between insulating layers of an insulating base formed by laminating a plurality of insulating layers made of ceramic. A ceramic multi-layer wiring board arranged, wherein the metallized wiring conductor for signal has an electrical resistivity greater than an electrical resistivity of the metallized wiring conductor for power supply, and a thickness of the metallized wiring conductor for power supply. It is characterized by being thicker than the thickness.

According to the ceramic multilayer wiring board of the present invention, the electrical resistivity of the metallized wiring conductor for signal is made larger than the electrical resistivity of the metallized wiring conductor for power supply, and the thickness of the metallized wiring conductor for signal is reduced for the power supply. Because it was thicker than the metallized wiring conductor,
The larger the thickness of the signal metallized wiring conductor, the smaller the ratio of the variation of the printed thickness to the thickness of the signal metallized wiring conductor, thereby reducing the variation of the electrical resistance value of the signal metallized wiring conductor.

Further, since the electrical resistivity of the signal metallized wiring conductor is increased, the sheet resistance of the signal metallized wiring conductor does not change even if the thickness of the signal metallized wiring conductor is increased accordingly.

Further, since the metallized wiring conductor for power supply is thinner than the metallized wiring conductor for signal, lamination failure is unlikely to occur between the upper and lower insulating layers sandwiching the metallized wiring conductor for power supply.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a ceramic multilayer wiring board according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is a sectional view showing an embodiment of a ceramic wiring board according to the present invention. In FIG. 1, reference numeral 1 denotes an insulating base.

The insulating substrate 1 is made of, for example, an electrically insulating material such as an aluminum oxide sintered body, an aluminum nitride sintered body, a mullite sintered body, a silicon carbide sintered body, a silicon nitride sintered body, and a glass ceramic. Insulating layers 1a, 1b, 1 made of
c, 1d, and 1e are laminated and integrated, and has a mounting portion A in the center of the upper surface on which a semiconductor integrated circuit element (not shown) is mounted, and a lower surface having a connection surface connected to an external electric circuit board (not shown). Is formed.

The insulating substrate 1 is made of, for example, each of the insulating layers 1a to 1e.
Is made of an aluminum oxide sintered body, a suitable organic binder and a solvent are added to raw material powders such as aluminum oxide, silicon oxide, calcium oxide, and magnesium oxide to form a slurry. A ceramic green sheet which is formed into a sheet shape by employing a well-known doctor blade method and which becomes each of the insulating layers 1a to 1e is prepared, and thereafter, these ceramic green sheets are subjected to an appropriate punching process, and at the same time, in a predetermined order. The ceramic green sheets are laminated to form a ceramic green sheet laminate, and the ceramic green sheet laminate is fired at a temperature of about 1600 ° C. in a reducing atmosphere.

Between the insulating layers 1a and 1b and between 1b and 1c of the insulating base 1, there are metallized wiring conductors 2 and 3 for power supply for supplying power to the semiconductor integrated circuit element.
Are applied in a wide area pattern over substantially the entire surface between these insulating layers.

The power metallized wiring conductors 2 and 3
Are metallized wiring conductors for power supply for supplying power of different potentials to the semiconductor integrated circuit element.

The metallized wiring conductors 2 and 3 for power supply are made of a metal powder of a high melting point metal such as tungsten or molybdenum. And the electric resistivity is, for example, 10 μΩ
Cm, and its thickness is about 10 μm. The sheet resistance at this time is about 10 mΩ.

Since the metallized wiring conductors 2 and 3 for power supply are as thin as about 10 μm, the metallized wiring conductors 2 and 3 between the insulating layers 1a and 1b and between 1b and 1c sandwiching the metallized wiring conductors 2 and 3 for power supply are sandwiched. Lamination failure is unlikely to occur. Further, since the electric resistivity is as low as about 10 μΩ · cm and the pattern has a wide area, a sufficiently low electric resistance value can be obtained as a metallized wiring conductor for power supply even if the thickness is as thin as about 10 μm. .

If the metallized wiring conductors 2 and 3 for power supply are made of, for example, tungsten powder metallization, the metallized wiring conductors 2 and 3 are obtained by adding a suitable organic binder and a solvent to a tungsten powder having a particle size of about 1.2 μm and mixing them. For example, the paste is printed on the upper surface of the insulating layer 1b and the upper surface of the insulating layer 1c in a predetermined wide area pattern by using a conventionally known screen printing method, and is fired together with the ceramic green sheet laminate serving as the insulating substrate 1. Thereby, a large-area pattern covering substantially the entire surface between the insulating layers is provided between the insulating layers 1a and 1b and between 1b and 1c of the insulating base 1.

Between the insulating layers 1c and 1d and between 1d and 1e of the insulating base 1, a signal metallized wiring conductor 4 for sending and receiving signals to and from the semiconductor integrated circuit element has a width of 100 μm. Many are attached in a fine pattern.

The signal metallized wiring conductor 4 is made of metal powder of a high melting point metal such as tungsten or molybdenum. And its electrical resistivity is about 20 μΩ · cm and its thickness is about 20 μm. The sheet resistance at this time is 10 m, which is the same as that of the metallized wiring conductors 2 and 3 for power supply.
About Ω. Therefore, even if the thickness of the signal metallized wiring conductor 4 is large, it is possible to realize a predetermined electric resistance value as the signal metallized wiring conductor 4.

Since the signal metallized wiring conductor 4 is as thick as about 20 μm, a metal paste to be the signal metallized wiring conductor 4 is printed and coated on the upper surface of the insulating layer 1d and the upper surface of the insulating layer 1e as described later. Even if a thickness variation of about 4 μm occurs in the printing thickness, the ratio of the thickness variation to the thickness of the signal metallized wiring conductor 4 becomes small. The variation is small, and is actually as small as about ± 10% of the design value.
Therefore, when a signal is input / output to / from the semiconductor integrated circuit device via the signal metallized wiring conductor 4, malfunction or inoperability of the semiconductor integrated circuit device is unlikely to occur.

If the metallized wiring conductors 4 for signal are made of, for example, metallized tungsten powder, a metal paste obtained by adding and mixing an appropriate organic binder and a solvent to tungsten powder having a particle size of about 2.5 μm is used. ,
For example, a predetermined pattern is printed on the upper surface of the insulating layer 1d and the upper surface of the insulating layer 1e by using a conventionally known screen printing method, and the printed pattern is fired together with the ceramic green sheet laminate serving as the insulating substrate 1, thereby forming the insulating substrate 1. The width between the insulating layers 1c and 1d and between 1d and 1e is 10
It is deposited in a predetermined pattern of about 0 μm.

The signal metallized wiring conductor 4 has a pattern width as small as about 100 μm even though the thickness of the signal metallized wiring conductor 4 is as large as, for example, 20 μm. In addition, a metal paste serving as a metallized wiring conductor for signal is applied to the insulating layers 1c and 1c.
It does not satisfactorily dig into the ceramic green sheet of d · 1e and does not cause lamination failure between the insulating layers 1c and 1d and between 1d and 1c.

Further, the insulating layers 1a to 1d of the insulating substrate 1 are vertically penetrated through the insulating layers 1a to 1d from the metallized wiring conductors 2 and 3 for power supply and the metallized wiring conductor 4 for signal, and the mounting portion A on the upper surface of the insulating substrate 1 is formed. Power supply via conductor 5a
6a and the signal via conductor 7a are formed, and the power supply metallized wiring conductors 2 and 3 and the signal metallized wiring conductor 4 are formed on the insulating base via the power supply via conductors 5a and 6a and the signal via conductor 7a. It is electrically led to the mounting portion A at the center of the upper surface.

The power supply via conductors 5a and 6a and the signal via conductor 7a are made of metal powder of a high melting point metal such as tungsten or molybdenum. And it contains about 5 to 20% by weight of a ceramic component. As described above, the power supply via conductors 5a and 6a and the signal via conductor 7a contain about 5 to 20% by weight of the ceramic component, so that the power supply via conductors 5a and 6a and the signal via conductor 7a and the insulating base 1 Between the power supply via conductors 5a.
The generation of cracks in the insulating base 1 around the 6a and the signal via conductor 7a is effectively prevented.

The power supply via conductors 5a and 6a and the signal via conductor 7a are provided on the ceramic green sheets to be the respective insulating layers 1a to 1e of the insulating base 1 by the power supply via conductors 5a and 6a.
a and a via hole for accommodating the signal via conductor 7a and, for example, when the power supply via conductors 5a and 6a and the signal via conductor 7a are made of molybdenum powder metallized, the particle size is about 2 μm. A metal paste obtained by adding and mixing a ceramic component substantially the same as the ceramic component contained in the insulating substrate 1 and a suitable organic binder / solvent to the molybdenum powder is introduced into the through hole by using a conventionally well-known filling method. By filling and firing this together with the ceramic green sheet laminate serving as the insulating base 1, the insulating bases 1a to 1d are vertically penetrated from the metallized wiring conductors 2 and 3 for the power supply and the metallized wiring conductor 4 for the signal. It is formed so as to be led out to the mounting portion A on one upper surface.

Thus, according to the present invention, it is possible to provide a ceramic multilayer wiring board in which the variation in the electrical resistance of the metallized wiring conductor for signal is small and there is no lamination failure between the upper and lower insulating layers sandwiching the metallized wiring conductor for power supply.

The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the gist of the present invention. For example, in the example of the above-described embodiment, the electrical resistivity of the signal metallized wiring conductor is increased by increasing the particle size of the high melting point metal powder of the metal paste to be the signal metallized wiring conductor to about 2.5 μm. However, the electrical resistivity of the metallized wiring conductor for signal may be increased by adding a ceramic component to the metallized high melting point metal powder to be the metallized wiring conductor for signal.

[0041]

According to the ceramic multilayer wiring board of the present invention, the electrical resistivity of the metallized wiring conductor for signal is made larger than the electrical resistivity of the metallized wiring conductor for power supply and the thickness of the metallized wiring conductor for signal is reduced. Because it is thicker than the metallized wiring conductor for power supply,
Since the thickness of the metallized wiring conductor for signal is thicker, the ratio of the variation of the printed thickness to the thickness of the metallized wiring conductor for signal becomes smaller, and the variation in the electrical resistance value of the metallized wiring conductor for signal becomes smaller. It is difficult to cause malfunction or inoperability of the semiconductor integrated circuit device to be used.

Since the electrical resistivity of the signal metallized wiring conductor is increased, the sheet resistance of the signal metallized wiring conductor does not change even if the thickness of the signal metallized wiring conductor is increased. A predetermined resistance value as a metallized wiring conductor can be realized.

Further, since the metallized wiring conductor for power supply is thinner than the metallized wiring conductor for signal, lamination failure is unlikely to occur between the upper and lower insulating layers sandwiching the metallized wiring conductor for power supply.

As described above, according to the present invention, there is provided a ceramic multi-layered wiring board capable of properly and stably operating a semiconductor integrated circuit element mounted thereon with a small variation in electric resistance value of a metallized wiring conductor for signal. We were able to.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of an embodiment of a ceramic multilayer wiring board of the present invention.

[Explanation of symbols]

1 ... Insulating substrate 1a, 1b, 1c, 1d, 1e ... Insulating layer 2, 3 ... Metallized wiring conductor for power supply 4 ... Metallized wiring conductor for signal

Claims (1)

[Claims] 1. A ceramic multilayer wiring board comprising a metallized wiring conductor for signal and a metallized wiring conductor for power supply disposed between insulating layers of an insulating base formed by laminating a plurality of insulating layers made of ceramic. The ceramic multi-layer wiring board, wherein the metallized wiring conductor for signal has an electrical resistivity greater than an electrical resistivity of the metallized wiring conductor for power supply, and a thickness thereof is larger than a thickness of the metallized wiring conductor for power supply. .