JPH0645762A - Multilayer ceramic board and manufacture thereof - Google Patents

Abstract

PURPOSE:To dispense with processes where holes are bored in green sheets and conductive paste is filled into via holes so as to enable a multilayer ceramic board to be simplified in manufacturing process and lessened in cost, where a semiconductor LSI and chip parts are mounted on the multilayer ceramic board and interconnected to one another. CONSTITUTION:An eyelet metal structure 3 is press-fitted into a green sheet 1 at a prescribed position, and an electrode pattern 4 is printed thereon with conductive paste. A required number of the green sheets 1 where the different electrode patterns 4 are printed are laminated and burned into a multilayer ceramic board. By this constitution, a multilayer ceramic board can be simplified in manufacturing process and lessened in cost.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multilayer ceramic wiring board for mounting semiconductor LSIs, chip parts, etc. and interconnecting them, and a method for manufacturing the same.

[0002]

2. Description of the Related Art In recent years, a ceramic substrate is superior in heat conductivity, heat resistance, and chemical durability to an organic material substrate, so that its use is expanding as an alternative to the organic material substrate. In addition, with the miniaturization and diversification of electronic devices, they have come to be widely used as substrates capable of high-density wiring and high-density mounting. Furthermore, it is expected that demand for semiconductor bare chip mounting boards will increase in the future, making fine wiring easy and
It is considered that a method for manufacturing a highly reliable ceramic substrate is needed.

An example of a conventional ceramic circuit board will be described below with reference to FIG. As shown in FIG. 6, a conventional ceramic substrate is a ceramic substrate made of alumina or the like, containing silver powder or copper powder as a main component, and borosilicate glass or borosilicate glass and a thermoplastic resin added to the conductive substrate. The paste is printed to form the conductor layer. For the conductor layer, a via hole (hereinafter referred to as a hole) 10 is formed in the green sheet 9, a conductive paste is filled therein, and an electrode pattern 11 is formed by the conductive paste. Further, a desired number of green sheets on which a conductor layer different from the green sheet 9 is formed are laminated. The ceramic circuit board is completed by firing the ceramic board thus configured.

[0004]

However, making holes 10 in the green sheet 9 and filling the holes with the conductive paste requires a large number of steps. In the case of multiple layers, the number of steps increases by the number of layers. become. In addition, there are many process control conditions such as the conditions for punching holes 10 in the green sheet 9 and the filling conditions of the conductive paste, which causes deterioration of the quality of the substrate.

The present invention solves the above problems, and an object of the present invention is to provide a ceramic substrate that simplifies the process and contributes to cost reduction, and a method for manufacturing the same.

[0006]

In order to achieve the above-mentioned object, the present invention prepares a green sheet containing at least an organic binder and a plasticizer on a glass / ceramic low temperature sintering substrate material, and the green sheet is made of metal. Then, press fit the minute cove-shaped structure. Alternatively, a structure made of metal is fixed at a desired position when the green sheet is manufactured, and the green sheet constituent material is poured into the structure to manufacture a green sheet containing the structure. Then, an electrode pattern is printed on the green sheet with a conductive paste. This is repeatedly laminated for a desired number of sheets. Next, the laminate is fired to produce a ceramic substrate.

[0007]

As described above, according to the present invention, since the green sheet including the metallic cog-like structure is produced, it is possible to omit the punching of the green sheet and the filling of the conductive paste.

[0008]

(Embodiment 1) Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. In order to produce the green sheet 1, a composition (MLS-19 manufactured by Nippon Electric Glass Co., Ltd.) in which lead borosilicate glass powder and alumina powder as a ceramic material were mixed at a weight ratio of 50:50 was used. This glass-ceramic powder was used as an inorganic component, polyvinyl butyral as an organic binder, di-n-butyl phthalate as a plasticizer, and a mixed solution of toluene and isopropyl alcohol (weight ratio 30:70) as a solvent to form a slurry. This slurry was formed into a sheet on an organic film by the doctor blade method.

Next, the sheet is peeled off from the film and fixed to the frame 2, and the main component having the shape as shown in FIG. 2 is copper, and the surface of which is gold-plated. did. The surface is plated with gold in order to prevent oxidation during debinding. In this embodiment, copper is the main component, but other metals such as silver or tungsten may be used.

Next, a glass frit (LS-0803 glass powder manufactured by Nippon Electric Glass Co., average particle size 2.5 μm) for obtaining adhesive strength to cuprous oxide powder (average particle size 3 μm)
Is added as an inorganic component with ethyl cellulose, which is an organic binder, together with a vehicle in which terpineol is dissolved, and mixed with a three-stage roll so as to have an appropriate viscosity. An electrode pattern is formed by a screen printing method. 4 was formed. The thickness of the green sheet 1 is about 250 μm.

Further, as shown in FIG. 3, the green sheet 1
A predetermined number of the printed sheets were stacked and thermocompression bonded to form a laminate. The thermocompression bonding conditions are a temperature of 80 ° C. and a pressure of 200 kg / cm ² . Next, through a binder removal step, a reduction step, and a firing step, printing and firing were performed on the surface layer using a copper paste, and a ceramic multilayer substrate could be obtained. In this embodiment, the cuprous oxide paste is used as the conductive paste, but other conductive pastes such as silver paste and copper paste may be used. In that case, the steps after lamination are a binder removal step, a firing step, a surface conductor printing, and a firing step.

(Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIGS.

As shown in FIG. 4, a metal structure 8 having the same composition as that of the first embodiment shown in FIG. 5 is fixed to a mold 5 having a constant depth, and is fixed to a projection 6 at a desired position. A green sheet slurry having the same composition as in Example 1 was poured from the inlet 7, the solvent component was dried, and the green sheet was peeled off from the mold. The following procedure was performed in the same manner as in Example 1.

[0014]

As is apparent from the above description of the embodiments, the present invention can be configured such that the holes of the green sheet and the holes are filled with the conductive paste at one time. In addition, there are few factors that deteriorate the quality such as the management of whether there is a hole or the filling condition of the paste, and since the conductive paste is not used for the via hole, the conduction failure of the paste that occurs in the steps of debinding and reducing does not occur. Therefore, it is possible to provide a multilayer ceramic substrate that can contribute to simplification of the process, improvement of reliability, and cost reduction, and a manufacturing method thereof.

[Brief description of drawings]

FIG. 1 is a sectional view of a green sheet of a ceramic substrate according to a first embodiment of the present invention.

FIG. 2 is a perspective view of the claw-like structure.

FIG. 3 is a sectional view of a laminated body of the multilayer ceramic substrate.

FIG. 4 is a sectional view of a green sheet forming die for a ceramic substrate according to a second embodiment of the present invention.

FIG. 5 is a perspective view of the same metal structure.

FIG. 6 is a sectional view of a conventional multilayer ceramic substrate.

[Explanation of symbols]

 1 Green sheet 3 Domed structure 4 Electrode pattern

Claims (4)

[Claims] 1. A green sheet containing at least an organic binder and a plasticizer is produced on a glass / ceramic low-temperature sintered substrate material, and a fine fit-like structure made of metal is press-fit into the green sheet, and the sheet is further formed. A multilayer ceramic substrate obtained by forming an electrode pattern with a conductor paste composition thereon, laminating a desired number of the green sheet and another green sheet having an electrode pattern formed thereon, and firing the laminated body. 2. A green sheet containing at least an organic binder and a plasticizer is produced on a glass / ceramic low-temperature sintered substrate material, and a fine fit-like structure made of metal is press-fit into the green sheet, and the sheet is further formed. A method for manufacturing a multilayer ceramic substrate, comprising forming an electrode pattern on the conductive paste composition, stacking a desired number of the green sheet and another green sheet having an electrode pattern formed thereon, and firing the stacked body. 3. A stopper structure is fixed in advance to a desired position in a mold having a constant depth, and a green sheet composition is poured into the mold to prepare a green sheet containing the structure. A multilayer ceramic substrate obtained by forming an electrode pattern on a sheet with a conductor paste composition, laminating a desired number of the green sheet and another green sheet on which an electrode pattern has been formed, and firing the laminated body. 4. A stopper structure is fixed in advance to a desired position in a mold having a certain depth, and a green sheet composition is poured into the mold to prepare a green sheet containing the structure, and further, A method for producing a multilayer ceramic substrate, comprising forming an electrode pattern on a sheet with a conductor paste composition, laminating a desired number of the green sheet and another green sheet on which an electrode pattern has been formed, and firing the laminated body.