JPS62296600A - Composite ceramic multilayer interconnection board and manufacture of the same - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a composite ceramic multilayer lock plate used for electronic circuit components such as hybrid integrated circuits, and a method for manufacturing the same.

(Prior Art) Ceramic wiring boards include ceramic wiring boards manufactured by the green method and ceramic wiring boards manufactured by the thick film method. Recent ceramic wiring boards have become more dense and highly functional, and composite ceramic multilayer wiring boards are now being developed, in which conductor layers, resistor layers, etc. are formed using the thick film method on ceramic wiring boards manufactured using the green method. Some of them have been put into practical use.

As shown in FIG. 3, a conventional composite ceramic multilayer wiring board has an internal conductor layer 2 mainly composed of powder of a high melting point metal such as Mo or W formed in an alumina ceramic 1. N4 layer 8 is formed on the exposed surface of internal conductor layer 2 exposed above through hole 5 by a method such as plating, and A
Those in which a noble metal layer 6 such as U is formed are generally known.

(Problems to be Solved by the Invention) When manufacturing electronic circuit components using the composite ceramic multilayer wiring board shown in FIG.
Outer conductor layer mainly composed of powder, )1. Thick film circuits such as resistor layers are formed using uOx powder as a main component, but since these thick film circuits are usually sintered in the atmosphere, the inner conductor layer and the metal layer formed on the exposed surface of the inner conductor layer are It is necessary to prevent it from oxidizing. However, using a composite ceramic wiring board with the above structure,
There is a drawback that firing at a temperature of 30°F (°C) oxidizes the underlying internal conductor layer and metal layer.

As a countermeasure for this, Ag/P for low temperature firing (below 650℃)
Forming thick film circuits such as an external conductor layer mainly composed of d powder and a resistor layer mainly composed of It, u Oa powder,
I tried forming thick film circuits such as a curing type conductor layer and a carbon-based resistor layer, but compared to thick film circuits fired at high temperatures, these had a large '1' Cn (resistance variation rate) and were more reliable. It has the disadvantage of being inferior in gender.

(Means for Solving the Problems) An object of the present invention is to provide a composite ceramic multilayer wiring board and a method for manufacturing the same, which are free from the above-mentioned drawbacks.

As a result of various studies on the above-mentioned drawbacks, the present inventors formed an internal conductor layer mainly composed of high melting point metal powder such as Mo and W in alumina ceramics by exposing a part of the material to the surface using the green method. Then, glass paste is applied to the surface of the alumina ceramics, leaving approximately the center of the surface on the internal conductor layer exposed to the surface through the through hole, and fired in a neutral atmosphere to form a glass layer with via holes. When formed, it was confirmed that the underlying internal conductor layer, Ni layer, and Ag/Pd layer were not oxidized even when fired at a temperature of 800 to 950°C.

The present invention provides an internal conductor layer built into alumina ceramics with a part exposed on the surface, a Ni layer formed on the exposed surface of the internal conductor layer, an Ag/Pd layer formed on the Ni layer, and alumina ceramics. A composite ceramic multilayer wiring board consisting of a glass layer formed by providing via holes on the surface of the substrate and the Ag/Pd layer, and an internal conductor layer formed in the alumina ceramics by exposing a portion to the surface using the green method.

Next, a Ni layer is formed on the exposed surface of the internal conductor layer, and then a Ni layer is formed on the exposed surface of the internal conductor layer.
An Ag/Pd layer is formed on the i-layer, and then a glass paste is applied to the surface of the alumina ceramics, leaving approximately the center of the surface of the Ag/Pd layer, and is fired in a neutral atmosphere to form glass with via holes. The present invention relates to a method for manufacturing a composite ceramic multilayer wiring board in which layers are formed.

In the present invention, the materials forming the inner conductor layer include:
High melting point metals such as Mo, Mo/Mn, and W are used.

The Ni layer can be formed by plating, vapor deposition, applying Ni paste, and baking, and is not particularly limited.9 In the present invention, electroless Ni/P plating is used.

Ni by plating methods such as electroless Ni/B plating and electrolytic plating.
Preferably, a layer is formed. The thickness of the plating at this time varies depending on the surface roughness of the exposed surface of the internal conductor layer, but
．． A thickness of 5 to 8 μm is preferable, and a thickness of 1 μm or more is more preferable from the point of view of characteristic 1 workability since the Ni layer does not have a portion of the pinhole surface.

The Ag/Pd layer is formed by transfer.

There is a method of applying Ag/Pd paste and baking it by heat treatment, but there is no particular limitation. Preferably, the paste is formed by baking.

There is no particular restriction on the thickness of the Ag/Pd layer.

A thickness of 3 to 20 μm is preferable in terms of ease of workability since there are no pinholes in the Ag/Pd layer.

The glass used to form the glass layer is amorphous glass,
A crystallized glass that can be sintered in a neutral atmosphere is used. It is preferable to use glass having a softening point of 650° C. to the melting point of the Ni layer, since the glass will not diffuse into the alumina ceramics when forming a thick film circuit. If you use glass, which still has a higher free energy of oxide formation than high-melting point metals.

This is preferable because the high melting point metal does not oxidize even if the glass diffuses into the high melting point metal.

To bake the glass paste, use N2. Firing must be done in a neutral atmosphere such as Ar; firing in an oxidizing atmosphere will cause the Ni layer, internal conductor layer, etc. to oxidize. If firing in a reducing atmosphere, the organic binder in the glass paste will remain. This results in the disadvantage that the sintering of the glass is hindered.

The composite ceramic multilayer wiring board according to the present invention includes glass-containing Ag/Pd, Ag/Pt, Pt, glass-containing glass on the via hole and the glass layer around the via hole as necessary.
An outer conductor layer mainly composed of Au or the like.

A thick film circuit such as a resistor layer mainly composed of RuOs may be formed.

(Example) The present invention will be explained below with reference to Examples.

Example 1 Two alumina ceramic green sheets (alumina purity 96w/i1'%) (hereinafter referred to as green sheets) with a thickness of 0.8 mm were cut into a size of 50 x 50 mm.

A hole (through hole) with a 1G diameter of 0.6 mm was formed in one of these sheets, and W paste (manufactured by Asahi Chemical Co., Ltd., trade name 3TW-1200) was then filled in the through hole, and the surface of one side was filled with the After drying, the same W paste was printed, and after drying, the green sheet was placed on top of another green sheet with the side with the W paste printed facing down, and then heated at 100°C and 6 kg/c-. After that, the green sheet was sintered by heating and pressurizing at 1,600°C for 1 hour in a weakly reducing (H2) atmosphere, and the W paste was sintered, with a part of the material being exposed to the surface as shown in Figure 2. A ceramic wiring board was obtained in which an internal conductor layer 2 was formed in an exposed alumina ceramic 1.

Next, the exposed surface of the internal conductor layer 2 was activated with an activating solution (Yo3 activating solution manufactured by Nippon Kanigen Co., Ltd.).
P plating (manufactured by Nippon Kanigen, trade name f9-680) was performed, washed with water, and dried to form a Ni plating layer 3 with a thickness of 4 μm as shown in FIG.

Next, in the center of the upper surface of the Ni plating layer 3, an average grain size of 0
．． 80% by weight of 3 μm Ag powder and 20% by weight of Pd powder were mixed, and to 100 parts by weight of this mixture, 2 parts by weight of an acrylic binder (trade name: φ5200, manufactured by DuPont) and butyl carpitol acetate were added as an organic solvent. 1
Ag obtained by adding 0 parts by weight and kneading with three rolls /
Pd paste was printed to have a diameter of 0.4 vtse and a thickness of 10 μm after heat treatment, and after drying, it was heat treated at a temperature of 750 °C for 10 minutes in a reducing atmosphere to form Ag.
/ Pd layer 9 was formed.

After this 810m 50wt%, BaO24w ii s
A glass with a softening point of 860°C consisting of 6% by weight of Altos and 20% by weight of Ca0 was ground to an average particle size of 3 μm, and 100 parts by weight of the ground glass powder was mixed with an acrylic binder (manufactured by DuPont, trade name 5200). )2
10 parts by weight of butylcarpitol acetate as an organic solvent were added, and the mixture was kneaded with three rolls to form a paste. Next, the glass paste was mixed with Ag/Pd
A hole of 0.2 mm in diameter was left in the center of the layer 9, and printed on the surface of the alumina ceramics 1 in a ring shape with a width of 0.4 m and a thickness of 40 μm after drying. After drying, heat treatment was performed at a temperature of 900° C. for 20 minutes in an N2 atmosphere to obtain a composite ceramic multilayer wiring board in which a glass layer 4 and via holes 7 were formed. Note that in FIGS. 1 and 2, 5 is a through hole.

Example 2 The internal exposed surface of the ceramic wiring board obtained in Example 1 was activated using the same activation solution as in Example 1, and subjected to primary electroless Nl/B plating (manufactured by Nippon Kanigen Co., Ltd., product name 8B). -5
5), washed with water and dried to form a Ni plating layer with a thickness of 5 μm, and then the same Ag/Pd paste as in Example 1 was used in the center of the upper surface of the Ni plating layer. An Ag/Pd layer with a thickness of 10 μm was formed using the method described above. After this, 5iOz 54% by weight.

Al! os 13% by weight, Zn07 weight 1:%, Ca0
Softening point of 25 wt-i% and Mg01 wt% is 8
Glass at 20°C was ground to an average particle size of 3 μm, and 2 parts by weight of an acrylic binder (manufactured by DuPont, trade name: 5200) and butylcarpitol lO-1 were added as an organic solvent to 100 parts by weight of the ground glass powder. 10 parts by weight of acetate was added and kneaded using three rolls to form a paste. Next, the above glass paste was applied to the central part on the Ag/Pd layer in the same manner as in Example 1 to a diameter of 0.
．． Leave 2 m, and form a ring shape with a width of 0.4 mm over the surface of the alumina ceramic, and a thickness of 5 mm after drying.
A composite ceramic multilayer wiring board was obtained by printing to a thickness of 0 μm, drying, and heat-treating at 850° C. for 10 minutes in an N3 atmosphere to form a glass layer and via holes.

Example 3 An N1 plating layer with a thickness of 3 μm was formed on the internal exposed surface of the ceramic wiring board obtained in Example 1 using the same plating solution as in Example 2 and in the same manner as in Example 1, and further Ni plating was applied. Ag was applied to the center of the upper surface of the layer to a thickness of 12 μm in the same manner as in Example 1 using the same Ag/Pd paste as in Example 1.
/ A Pd layer was formed. After this, Cu-based multilayer glass paste (manufactured by Nichiryo Ferro Denshi Co., Ltd., trade name 1005RCu)
in the same manner as in Example 1 and in the same shape as in Example 1,
Then, it was printed to a thickness of 30 μm after drying.

After drying, it was heat-treated in a N2W atmosphere at a temperature of 850° C. for 1 hour to obtain a composite ceramic multilayer wiring board in which a glass layer and via holes were formed.

Comparative Example 1 A Ni plating layer with a thickness of 4 μm was formed on the exposed surface of the internal conductor layer of the ceramic wiring board obtained in Example 1 using the same method as in Example 1 and using the same plating solution as in Example 1. Further, electroless Au plating (manufactured by Nippon Engelhard Co., Ltd., trade name ATOMBX-PC) was performed on the top surface, washed with water, and dried to form a 1 μm thick Au plating layer to obtain a composite ceramic multilayer wiring board. .

Next, high temperature sintered glass was added to the inside of the via hole and on the glass layer around the via hole of the composite ceramic multilayer wiring board obtained in each example, and on the Au plating layer of the composite ceramic multilayer wiring board obtained in Comparative Example 1. Ag/Pd paste (manufactured by Nichika Matsusei Co., Ltd., trade name≠4846) was printed, and after drying, the glass-containing Ag/Pd paste was baked by heat treatment at a temperature of 850 °C for 10 minutes in the air, and the glass-containing Ag/Pd paste was printed.
A Pd layer was formed. Then this glass-containing Ag1Pd
The connection resistance between the layer and the internal conductor layer and the presence or absence of oxidation of the internal conductor layer were observed. As a result, the composite ceramic multilayer wiring boards obtained in each example had a connection resistance of 1 mΩ or less with a small fluctuation rate, and no oxidation of the internal conductor layer was observed. On the other hand, in the composite ceramic multilayer wiring board obtained in Comparative Example 1, electrical continuity could not be obtained, and the internal conductor layer was oxidized. Similar effects were also obtained by forming a glass-containing Pt layer, a glass-containing Au layer, or a glass-containing Ag/Pi layer instead of the glass-containing Ag/Pd layer.

(Effects of the Invention) In the composite ceramic multilayer wiring board according to the present invention, the internal conductor layer does not oxidize and has high reliability in terms of electrical characteristics.

It is extremely suitable industrially.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional side view of a composite ceramic multilayer wiring board according to an embodiment of the present invention, FIG. 2 is a cross-sectional side view of a ceramic wiring board used in a composite ceramic multilayer wiring board according to an embodiment of the present invention, and FIG. The figure is a cross-sectional side view of a conventional composite ceramic multilayer wiring board. Explanation of symbols 1...Alumina ceramics 2...Inner conductor layer 3
...N1 plating layer 4...Glass layer 5.
...Through hole 6...Precious metal layer 7...
Via hole 8...Ni19...Ag
/ Pd layer ZI diagram! 2nd [2] Light 3 Lumina Yara St in the mouth, ζ5 9:A>/r〆san

Claims (1)

[Claims] 1. An internal conductor layer built into alumina ceramics with a part exposed on the surface, a Ni layer formed on the exposed surface of the internal conductor layer, and an Ag/A layer formed on the Ni layer. A composite ceramic multilayer wiring board consisting of a Pd layer and a glass layer formed by providing via holes on the surface of an alumina ceramic and an Ag/Pd layer. 2. Form an internal conductor layer in alumina ceramics by exposing a part to the surface using the green method, then form a Ni layer on the exposed surface of the internal conductor layer, and then form an Ag/conductor layer on the Ni layer.
A Pd layer is formed, and then a glass paste is applied to the surface of the alumina ceramics, leaving approximately the center of the surface of the Ag/Pd layer, and is fired in a neutral atmosphere to form a glass layer with via holes. A manufacturing method for a characteristic composite ceramic multilayer wiring board.