JPH03150895A - Multilayer circuit board and manufacture thereof - Google Patents

Abstract

PURPOSE:To enable high-speed transmission by lessening the permittivity of insulating layers between X-direction and Y-direction line wiring layers and power source layers or ground layers, and enlarging that of the insulating layers between the X-direction and Y-direction line wiring layers and between the power source layers or ground layers. CONSTITUTION:The permittivity of the insulating layers 2 between X-direction and Y-direction line wiring layers 3 and power source layers 4 or ground layers 4 is made to be smaller than that of the insulating layers 1 between the X- direction and Y-direction line wiring layers 3 and between the power source layers 4 or ground layers 4. Namely, an insulating material 1 provided with an air and a line wiring layers 3 on both faces and an insulating material 1 provided with a power source layer 4 or a ground layer 4 on both faces are composed of ceramics, etc., whose main component is mullite. As this result, the magnetic fields between the line wiring layers 3 and power source layers 4 or ground layers 4 are hardly generated, and the transmission of electric signals is not interfered. In this way, it becomes possible to transmit electric signals quickly.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a high-speed transmission multilayer circuit board and a method for manufacturing the same, and more particularly to a multilayer circuit board suitable for configuring a functional module and a method for manufacturing the same.

[Conventional technology]

In recent years, integrated circuits such as LSIs have come to be mounted directly on multilayer circuit boards in order to meet demands for higher speeds and higher densities. Conventionally, a sintered body mainly made of alumina is used as an insulating material in the multilayer circuit board used in the above mounting method. However, such substrates generally have a major drawback in that the transmission speed of electrical signals is slow.

On the other hand, integrated circuits such as LSIs generally require a power source having multiple potentials. These power sources are often provided by providing a substrate with a power layer outside the substrate, which often poses an obstacle to high-speed transmission.

[Problem to be solved by the invention]

Signals transmitted through the conventional integrated circuits are difficult to transmit at high speed due to potential drop due to the dielectric properties of insulating materials and waveform disturbances due to noise, etc., and it has been desired to solve these problems. SUMMARY OF THE INVENTION An object of the present invention is to provide a multilayer circuit board that is less affected by potential fluctuations and reflected waves, and is capable of high performance and high-speed transmission, and a method for manufacturing the same.

[Means for Solving the Problems] As a result of intensive study on the above-mentioned problems, the present inventors found that the object of the present invention can be achieved by the following means.

That is, the present invention provides a multilayer circuit board formed by alternately laminating conductor layers and insulating layers, in which the conductor layer consists of line wiring layers in the X direction and Y direction, and a power supply layer or a ground layer, and The dielectric constant of the insulating layer between the line wiring layer in the X direction and the power layer or ground layer is the same as the dielectric constant of the insulating layer between the line wiring layer in the X direction and the line wiring layer in the Y direction, and the insulation between the power layer or ground layer The present invention relates to a multilayer circuit board characterized in that the dielectric constant is smaller than the dielectric constant of the layers.

Furthermore, the present invention relates to a method for manufacturing a multilayer circuit board, characterized by laminating a plurality of board units each having a small number of conductor layers (each having one conductor layer) on both upper and lower surfaces of an insulating layer.

The present invention will be explained in more detail below.

In addition to conventionally used metals, the conductor layer of the present invention also uses superconducting materials in order to further reduce resistance. In addition to the conventional printed circuit wiring, the circuit wiring can also be formed by a vapor deposition method or a plating method.

The material used for the insulating layer between the line wiring layer in the X direction and the Y direction and the power supply layer or the ground layer in the present invention preferably has a particularly low dielectric constant.

For example, vacuum, air, gas (tle, Ne, ^r,
N, 0, etc.), liquids (helium, nitrogen, etc.), etc. are preferably used.

The material used for the insulating layer between the X-direction line wiring layer and the Y-direction line wiring layer and the insulating layer between the power supply layer or the ground layer of the present invention is the material used for the insulation layer between the line wiring layer and the power supply layer or the ground layer. A material having a dielectric constant higher than that of the insulating layer material is used. It goes without saying that "between the power supply layer or the ground layer" here refers to the space between them when one layer is the power layer or the ground layer and the other layer is the power layer or the ground layer.

The insulating layer material is preferably strong enough to maintain the shape of the multilayer circuit board, such as ceramics. Specific examples include at least one selected from alumina, silica, magnesia, zirconia, spinel, mullite, zircon, aluminum nitride, glass, and the like.

The multilayer circuit board of the present invention is manufactured by creating a board unit having at least one conductor layer on each of the upper and lower surfaces of an insulating layer, and then alternately stacking a plurality of these units.

For example, a board that has one line wiring layer in the X direction and one line wiring layer in the They are alternately laminated with the body insulating layers interposed therebetween. The substrates are preferably connected via conductors by a known solder connection method.

In order to reduce the effects of potential fluctuations and reflected waves that cause noise occurring in electrical signals, at least one of the insulating layers between the power supply layer or the ground layer of the laminate may be a capacitor with a high dielectric constant. Particularly preferred.

Also, introducing a capacitor and/or a resistor into the circuit,
Alternatively, it is also preferable to mount them on a substrate, and a high-performance hybrid IC substrate can be obtained.

In order to further reduce wiring resistance, it is preferable to maintain the conductor layer at a lower temperature. Therefore, it is preferable to create a cavity between a substrate having X-direction and X-direction line wiring layers on both sides and a substrate having power supply layers or ground layers on both sides, and to flow a coolant such as liquid nitrogen into the cavity.

In order to further improve the performance of a multilayer circuit board, Si
It is particularly preferable to mount one or more semiconductors made of GaAs, etc. on the same substrate to form a functional module.

[For production]

The multilayer circuit board obtained according to the present invention eliminates factors that inhibit the transmission of electrical signals, making it possible to improve performance and achieve high-speed transmission. Furthermore, performance can be further improved by lowering the resistance of wiring, mounting semiconductors, and incorporating capacitors and resistors into the circuit.

When the multilayer circuit board of the present invention is used, for example, in large-scale electronic computers, it greatly contributes to improving their performance.

〔Example〕

The present invention will be explained in more detail below using examples.

(Example 1) A cross-sectional view of a multilayer circuit board used in this example is shown in FIG. In the figure, l is a ceramic insulating material that forms an insulating layer between the X direction and the line wiring layer in the X direction and between the power supply layer or the ground layer, and 2 is the ceramic insulating material that forms the insulating layer between the This is air that forms an insulating layer between the power supply layer or the ground layer. Further, 3 is a conductive material forming the X direction or a line wiring layer in the X direction, and 4 is a conductive material forming a power supply or ground layer. These conductor layers are connected to each other by solder shown at 5. Reference numeral 6 indicates a Kovar pin connected with gold-indium solder 7, and 8 and 9 indicate semiconductor components each having different characteristics and connected with solder 10.

Next, a method for producing a high-speed transmission circuit board according to the present invention will be explained. In the following description, "part" means weight (duram), and "%" means weight %.

Mullite powder with an average particle size of 2.5 μm (3A[20,・2
Sing) 72.0 parts, average particle size 1.0 μm quartz powder (Sing) 25.3 parts, average particle size 0.6 a
m spinel powder (AbOi・Mg0) 2.7 parts,
As a resin, 5.9 parts of polyvinyl butyral having an average degree of polymerization of 100 was placed in a ball mill and dry mixed for 3 hours. Furthermore, butyl phthalyl glycolate 1 is used as a plasticizer.
．． 9 d, trichlorethylene 46.0Id as solvent
, 17.0 ml of tetrachloroethylene, and 18.0 parts of n-butyl alcohol were added and mixed for 12 hours to prepare a slurry. Next, air bubbles are removed from the slurry by vacuum defoaming treatment, and the viscosity is adjusted.Next, the slurry is dried onto a siliconized polyester film support using a doctor blade to a thickness of 0.23+ ma. It is applied and dried in a furnace to create a ceramic green sheet. This ceramic green sheet was removed from the silicone-treated polyester film support and cut into 220W intervals.

Using a green sheet puncher, the ceramic green sheet thus produced was cut into two pieces with zero openings (the openings represent a square with a side of 200 mm; the same shall apply hereinafter), and one hole for a guide was formed.

After that, use this guide hole to fix the ceramic green sheet, and use the punching method to place it in a predetermined position with a diameter of 0.
．． I drilled a 15mm through hole. Furthermore, tungsten powder: nitrocellulose: ethyl cellulose: vorivinyl butyral: trichlorethylene = 100:3:1:
A conductor paste of 2:23 (weight ratio) was filled into the through holes made in the ceramic green sheet, and then the above-mentioned conductor paste was printed on both sides of the ceramic green sheet according to a predetermined circuit pattern by screen printing. Next, this ceramic green sheet was
The substrates were cut into M-shaped pieces, placed one by one in a substrate firing furnace, and heated at 200°C per hour in a mixed gas of nitrogen and hydrogen containing moisture.
The material was heated at a temperature increase rate of 1,630°C for 1°5 hours for sintering, and a substrate of 125m5+ size was created. A multilayer circuit in which a substrate having one line wiring layer in the X direction and one line wiring layer in the Y direction on both sides as conductor layers and a substrate having one power supply layer or ground layer on each side are alternately connected by solder. A board (high-speed transmission circuit board) was created.

On the same surface of this multilayer circuit board, 25 semiconductor components made of Si and GaAs were directly mounted with solder to form a functional module. The structure of the multilayer circuit board is such that the insulating layer between the line wiring layer and the power supply layer or ground layer is air, and the line wiring layer is made of air on both sides in the X direction and Y direction.
The insulating material having layers and the insulating material having one power layer or ground layer on both sides are made of ceramics containing mullite as a main component. Almost no magnetic field is generated between the line wiring layer and the power supply layer or ground layer, and the transmission of electrical signals is not disturbed. 4x speed (transmission was possible.

The functional module was immersed in liquid nitrogen and activated. As a result, the performance of semiconductor components made of GaAs is improved, and since liquid nitrogen is also filled between the line wiring layer and the power supply layer or ground layer, the wiring resistance of the conductor material is reduced, and when operated at room temperature. In comparison, it was possible to transmit electrical signals approximately twice as fast.

In addition, the insulating layers between the line wiring layers in the X and Y directions and between the power supply layer or the ground layer are made of ceramics whose main component is mullite, so they are necessary to maintain the shape of the multilayer circuit board. It was possible to create a high-speed transmission circuit board with strength and high reliability.

(Example 2) As shown in the cross-sectional view in FIG. 2, the capacitor component 12 and the resistor component 11 were introduced into the circuit, or the capacitor circuit 12 and the resistor circuit 11 were formed by a thick film method after baking the substrate. Other than that, two types of multilayer circuit boards were created in the same manner as in Example 1 above.

Twenty-five semiconductor components made of Si and GaAs were directly mounted on these multilayer circuit boards with solder to form a functional module. Compared to the functional module created in Example 1 above, the effects of potential fluctuations and reflected waves, which are the causes of noise occurring in electrical signals, can be reduced, eliminating potential fluctuations, matching with semiconductors, and generating reflected waves. It is now possible to prevent Since there is no disturbance in the waveform of the electrical signal, it is now possible to process the electrical signal sufficiently even if the frequency of the electrical signal is increased, making it possible to create a multilayer circuit board that can fully demonstrate the performance of semiconductor components. Both of the substrates obtained in this example can increase the frequency of electrical signals compared to the functional module created in Example 1, so the frequency of the electric signal can be increased by approximately 1
．． I was able to make it 5 times faster.

(Example 3) A material with a high dielectric constant is used for the power layer and the ground layer, or an insulating layer between the power layers with different potentials, and a high dielectric constant material is used for the power layer and the ground layer, or the power layers with different potentials are sintered. Functional modules were created in the same manner as in Examples 1 and 2 above, except that they were formed by the thick film method. The high dielectric constant material acted as a capacitor. As in Example 2 above, it is possible to reduce the effects of potential fluctuations and reflected waves that cause noise in electrical signals, eliminate potential fluctuations, achieve matching with the semiconductor, and prevent the occurrence of reflected waves. did it. Since there is no disturbance in the waveform of the electrical signal, even if the frequency loss of the electrical signal is increased, it can be processed satisfactorily, making it possible to create a multilayer circuit board that fully demonstrates the performance of semiconductor components.

Compared to the functional module created in Example 1, since the frequency of the electrical signal can be increased, the speed can be substantially increased by about 1.5 times as in Example 2.

(Example 4) A functional module was created in the same manner as in Examples 1 to 3 above, except that the blending amount of ceramic raw material powder, conductor material, firing atmosphere, and firing temperature were changed as shown in Table 1. In either case, the same performance as in Examples 1 to 3 was obtained.

(Margin below overlapping) (Example 5) C11% Au5pts peg/pd as conductor material
s^g/Pt by thick film method or thin film method (vapor deposition or plating method)
Functional modules were created in the same manner as in Examples 1 to 4 above, except that they were formed using the following methods. Since the wiring resistance could be reduced, deformation of the waveform of the electrical signal due to voltage drop was reduced, and the transmission speed of the electrical signal was approximately 1.1 times faster than that of the functional modules produced in Examples 1 to 4 above.

(Example 6) A functional module was created in the same manner as in Examples 1 to 4 above, except that a superconducting material was used as the conductor material. By operating the superconducting material used as the conductor at a temperature below the temperature at which superconductivity occurs, it was possible to reduce the wiring resistance to almost zero. The above operations were mostly carried out in liquid nitrogen. Therefore, there was almost no deformation of the waveform of the electrical signal due to voltage drop, and the transmission speed of the electrical signal was approximately 1.1 to 1.5 times faster than the functional modules created in Examples 1 to 5 above.

(Example 7) Introducing capacitor parts and resistance parts into the circuit, or
A multilayer circuit board (high-speed transmission circuit board) was produced in the same manner as in Examples 4 and 5 above, except that the capacitor circuit and the resistor circuit were formed by the thick film method after baking the board. Twenty-five semiconductor components made of Si and GaAs were directly mounted on this multilayer circuit board by soldering to form a functional module. Compared to the functional module created in Example 1, the influence of potential fluctuations and reflected waves, which are the causes of noise occurring in electrical signals, can be reduced, eliminating potential fluctuations and matching with semiconductors, resulting in the generation of reflected waves. was able to be prevented. Since there is no disturbance in the waveform of the electrical signal, it becomes possible to process the electrical signal sufficiently even if the frequency of the electrical signal is increased, making it possible to create a multilayer circuit board that can fully demonstrate the performance of semiconductor components. Compared to the functional modules created in Examples 4 and 5 above, since the frequency of the electrical signal could be increased, the transmission speed could be substantially increased by about 1.5 times.

〔Effect of the invention〕

According to the present invention, the dielectric constant of the insulating layer between the line wiring layer in the X direction and the Y direction and the power supply layer or the ground layer is reduced, and the dielectric constant of the insulating layer between the line wiring layer in the X direction and the Y direction and the power supply layer or the ground layer is reduced. By increasing the size of the insulating layer between the layers, the magnetic field that suppresses the transmission of electrical signals can be reduced, making high-speed transmission possible, and creating a highly stable multilayer circuit board that can maintain its shape. . Moreover, by mounting compound semiconductors such as St and GaAs as semiconductor components and incorporating capacitors and resistors into the circuit, a multilayer circuit board with even higher performance and higher speed transmission can be obtained.

[Brief explanation of the drawing]

An embodiment of the multilayer circuit board of the present invention is shown in cross-sectional views in FIGS. 1 and 2. FIG. 1: Ceramic insulating material forming an insulating layer between the line wiring layer in the X direction and the Y direction, and between the power supply layer or the ground layer 2: The ceramic insulating material forming the insulation layer between the line wiring layer in the X direction and the Y direction and the power supply layer or the ground layer Insulating material 3 forming an insulating layer between: Conductor material 4 forming a line wiring layer in the X direction or Y direction: Conductor material 5 forming a power supply layer or ground layer: Solder for board connection 6: Kovar pin 7: Gold - Indium solder 8: Si semiconductor component 9: Semiconductor component such as GaAs that has different characteristics from Si semiconductor components 1O 22-ring conductor component Connecting solder 1: Resistance component or resistance circuit

Claims (13)

[Claims] 1. In a multilayer circuit board formed by alternately laminating conductor layers and insulating layers, the conductor layer consists of a line wiring layer in the X direction and the Y direction and a power supply layer or a ground layer, and the line wiring layer in the X direction and the Y direction. The dielectric constant of the insulating layer between the and the power layer or ground layer is smaller than the dielectric constant of the insulating layer between the A multilayer circuit board characterized by: 2. The dielectric constant of the insulating layer between the power layer and the ground layer, or between the power layers with different potentials, is higher than the dielectric constant of the insulating layer between the line wiring layer in the X direction and the Y direction and the power layer or the ground layer. The multilayer circuit board according to claim 1, which is large. 3. The insulating layer between the line wiring layer in the X direction and the Y direction and the power supply layer or the ground layer is made of air, gas, liquid,
The multilayer circuit board according to claim 1, which is a vacuum. 4. 3. The multilayer circuit board according to claim 1, wherein the insulating layer between the X-direction and Y-direction line wiring layers and the insulating layer between the power supply layer or the ground layer are made of ceramic. 5. The insulating layer between the line wiring layers in the X direction and the Y direction and the insulating layer between the power supply layer or the ground layer are at least one selected from alumina, silica, magnesia, zirconia, spinel, mullite, zircon, aluminum nitride, and glass. 5. The multilayer circuit board according to claim 4, wherein the main component is a seed. 6. 2. The multilayer circuit board according to claim 1, wherein the conductor layer has a metal or a superconducting material as a main component. 7. The conductor layer constitutes a unit consisting of an X-direction line wiring layer, a Y-direction line wiring layer, and two power supply layers or ground layers, and the units are stacked in order, and the conductor layers constitute a unit consisting of an X-direction line wiring layer, a Y-direction line wiring layer, and two power supply layers or ground layers, and the units are laminated in order, and the The multilayer circuit board according to claim 1 or 2, wherein at least one of the insulating layers is formed of a capacitor. 8. The multilayer circuit board according to any one of claims 1 to 7, on which a semiconductor component is mounted. 9. 9. The multilayer circuit board according to claim 8, wherein the semiconductor components are composed of at least two types. 10. 8. The multilayer circuit board according to claim 1, wherein the multilayer circuit board forms a hybrid IC board incorporating a resistor circuit or a capacitor circuit or mounting a resistor component or a capacitor component. 11. The multilayer circuit board according to any one of claims 1 to 10, at least one of which is used in a large-sized computer. 12. A method for manufacturing a multilayer circuit board, comprising stacking a plurality of board units each having at least one conductor layer on both upper and lower surfaces of an insulating layer. 13. 13. The method of manufacturing a multilayer circuit board according to claim 12, wherein a plurality of said board units are stacked by a soldering method.