JP3100796B2 - Method for manufacturing multilayer ceramic substrate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a ceramic multilayer wiring board for mounting electronic components such as semiconductor LSIs and chip components and interconnecting them.

[0002]

2. Description of the Related Art In recent years, a glass / ceramic multilayer substrate which can be fired at a temperature of 1000 ° C. or less has been developed, and accordingly, gold, silver, copper, silver / palladium alloy, etc. have been used as conductive materials. . These metals have lower conductor resistance than conventionally used tungsten, molybdenum, and the like, and the equipment that can be used is safe and can be manufactured at low cost.

On the other hand, among these metals, noble metals such as gold, silver and palladium are expensive and have large price fluctuations. Therefore, it is desired to use a Cu electrode material which is inexpensive and has little price fluctuation.

Here, an example of a typical method for manufacturing a low-temperature sintered multilayer substrate will be described. There are three main types of low-temperature sintered multilayer substrates.

In the first method, silver is used for an inner layer electrode of a multilayer substrate, a desired number of green sheets of a low-temperature sintering substrate are laminated and fired in air, and then silver and palladium paste are printed on the uppermost layer. It is obtained by firing. This uses silver having a small impedance inside and silver / palladium having solder heat resistance as the uppermost layer.

The second method is a method in which silver is used for the internal electrodes in the same manner as the former, and copper is used for the uppermost layer. By using copper for the uppermost layer wiring, the impedance and the impedance are lower than those of the former silver and palladium. This is advantageous in terms of solder wetting. However, the copper used for the uppermost layer has a low eutectic temperature with silver, so that the
A low temperature fired copper paste at about 0 ° C. must be used. As a result, there are many problems in terms of adhesive strength and solder wetting.

Finally, the third method is to use copper electrodes for the inner layer and the uppermost layer. This method is the best in terms of conductor resistance, solder wettability, and cost, but all must be fired in a neutral atmosphere such as nitrogen, and its production is difficult. Further, in general, to use a copper electrode, C
u paste is screen-printed to form a wiring pattern, dried, and dried at a temperature equal to or lower than the melting point of Cu (850 to 950 °).
It is necessary to perform firing in a nitrogen atmosphere in which the oxygen partial pressure is controlled so that Cu is not oxidized and the organic components in the conductor paste are sufficiently burned without oxidizing Cu. It is difficult to control. In the case of multilayering, it is necessary to print and bake the insulating layer under the same conditions, and it is necessary to repeat baking each time after printing each paste, which leads to a longer lead time, which leads to an increase in cost of equipment and the like. have.

Therefore, a fourth method is disclosed in
No. 47833 has already disclosed a method in which a cupric oxide paste is used to produce a ceramic multilayer substrate, and the method includes three steps of a binder removal step, a reduction step, and a firing step. That is, a multilayer body is prepared using cupric oxide as a starting material of a conductor, and in the binder removal step, heat treatment is performed in an oxygen atmosphere sufficient for carbon and at a temperature sufficient to thermally decompose the internal organic binder. Next, a reduction step for reducing cupric oxide to copper and a firing step for sintering the substrate are established. Thereby, the control of the atmosphere at the time of firing becomes easy, and a dense sintered body can be obtained.

Incidentally, such a multilayer ceramic substrate undergoes shrinkage due to sintering during firing. The shrinkage due to sintering differs depending on the substrate material, green sheet composition, powder lot, and the like used. This causes several problems in the fabrication of a multilayer substrate.

First, in manufacturing a multilayer ceramic substrate, the uppermost layer wiring is formed after firing the inner layer wiring as described above. Therefore, if a contraction error of the substrate material is large, the uppermost layer wiring pattern and the inner layer electrode are formed. A problem arises that connection with the terminal cannot be made. Therefore, a land having a larger area than necessary must be formed in the uppermost electrode portion so as to allow a shrinkage error in advance, and there is a problem that it cannot be used for a circuit requiring high-density wiring. In addition, a method is used in which several screen plates for the uppermost layer wiring are prepared according to the shrinkage error and used according to the shrinkage ratio of the substrate. This method has a problem that it is uneconomical because many screen versions must be prepared.

On the other hand, if the uppermost layer wiring is performed at the same time as the inner layer baking, a large land is not required. However, in this case, the shrinkage error of the substrate itself still exists. As a result, printing may not be performed on a necessary portion, and a problem may arise in that a predetermined component position and a deviation occur in component mounting.

Second, the shrinkage ratio of a multilayer substrate formed by the green sheet laminating method differs depending on the film forming direction of the green sheet also in the width direction and the longitudinal direction. This also hinders the production of the ceramic multilayer substrate.

In order to minimize these shrinkage errors, not only the substrate material and the composition of the green sheet are controlled in the manufacturing process, but also the difference between powder lots and the laminating conditions (press pressure, temperature) are sufficiently controlled. Nevertheless, it is generally said that an error in the shrinkage ratio is about ± 0.5%.

Such a problem is a problem common to sintering of ceramics and glass-ceramics regardless of the multilayer substrate. Sintering of the substrate material occurs only in the thickness direction and shrinkage in the plane direction is zero. If the substrate can be manufactured, the above-mentioned problems can be solved, and it is industrially extremely effective.

In order to solve such problems, Japanese Patent Application No. Hei.
No. 257553, a green sheet containing at least an organic binder and a plasticizer is prepared on a glass / ceramic low-temperature sintered substrate material, an electrode pattern is formed with a conductive paste composition, and another green sheet having an electrode pattern formed thereon is formed. A green sheet made of an inorganic composition that is not sintered at the firing temperature of the glass / ceramic low-temperature sintered substrate material on both sides or one side of a green sheet laminate made of low-temperature sintered glass / ceramic after laminating a desired number of sheets. Are laminated, and the laminated body is fired, and thereafter, the inorganic composition which is not sintered is removed to prevent the shrinkage during firing from occurring in a planar direction.

Further, the glass having the electrode pattern formed thereon
After laminating a desired number of ceramic green sheets, a paste composition comprising an inorganic composition that is not sintered at the firing temperature of the glass / ceramic low-temperature sintering substrate material, at least an organic binder, and an organic solvent, on both surfaces or one surface of the green sheet laminate. A method for manufacturing a glass-ceramic substrate, in which shrinkage during firing is prevented from occurring in the planar direction by applying, drying and firing the laminate, and then removing the inorganic composition that does not sinter, has also been proposed. I have.

[0017]

However, it has been found that the above-described method of manufacturing a glass / ceramic substrate in which shrinkage during firing does not occur in a plane direction has the following problems.

That is, a glass-ceramic substrate is usually fired in a state of being placed on a base plate such as a sintered ceramic substrate, and when firing the substrate under appropriate conditions, the glass-ceramic substrate is fired during firing. When the glass in the interior softens, the substrate follows the surface shape of the base plate laid below and sinters while maintaining its shape due to the weight of the substrate. Therefore, if a flooring plate having no warp or unevenness is used, warpage and unevenness of the fired substrate can be prevented.

However, in order to prevent shrinkage in the planar direction as described above, after laminating green sheets made of an inorganic composition that does not sinter at the firing temperature on both sides or one side of the glass / ceramic green sheet laminate, Or, when a paste composition comprising a similar inorganic composition is applied and dried, and then subjected to a baking treatment, the warpage and irregularities of the ceramic substrate do not follow the surface shape of the base plate, and the green sheet before baking. There has been a problem that a warp having a shape different from the warp state of the laminate occurs. This is because the behavior of the glass-ceramic substrate during the firing process is suppressed by the inorganic composition layer that does not sinter at the firing temperature bonded to one or both surfaces of the glass-ceramic substrate, Is suppressed,
At the same time, it is considered that following the surface shape of the floor plate due to the weight of the substrate during softening of the glass is also inhibited.

However, the warpage and unevenness of the surface of the fired substrate become a major obstacle when components are mounted on the substrate, particularly when a bare LSI chip or the like is directly mounted on the substrate at a fine connection pitch.

On the other hand, there is a method in which an alumina sintered substrate or the like is placed thereon and baked while applying pressure to prevent the substrate from warping. However, since the alumina sintered substrate covers the surface of the ceramic laminate, a ceramic green substrate is used. There is a problem that it is difficult to control the firing conditions because the decomposition and scattering of organic substances such as a binder and a plasticizer contained in the sheet are prevented.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a method for manufacturing a multilayer ceramic substrate which does not shrink in a planar direction and can easily prevent warpage and unevenness of the substrate during firing. .

[0023]

According to a method of manufacturing a multilayer ceramic substrate of the present invention, a desired number of green sheets comprising at least an organic binder and a glass ceramic containing a plasticizer and having an electrode pattern formed by a conductive paste composition are prepared. After lamination, a green sheet laminate formed of an inorganic composition that does not sinter at the firing temperature of the glass ceramic is formed on both surfaces or one surface of the green sheet laminate, and the green sheet laminate on which the unsintered layer is formed Is bonded by thermocompression bonding to a floor plate made of a ceramic sintered substrate via the unsintered layer, followed by baking, and thereafter removing the unsintered layer. Also, as another manufacturing method,
After laminating a desired number of green sheets made of a glass ceramic containing at least an organic binder and a plasticizer and having an electrode pattern formed with a conductive paste, firing is performed on both sides or one side of the green sheet laminate at the firing temperature of the glass ceramic. An unsintered layer made of an inorganic composition that is not bonded is formed, and the green sheet laminate on which the unsintered layer is formed is bonded by thermocompression bonding to a floor plate made of a ceramic sintered substrate via a bonding layer. , Firing,
Thereafter, the unsintered layer and the bonding layer are removed.

Preferably, the unsintered layer is formed by laminating green sheets made of the above-mentioned inorganic composition, or by applying and drying a paste composition containing the inorganic composition.
Also, the bonding of the green sheet laminate to the ceramic sintered substrate can be preferably performed by heating and pressing, or even by applying an organic solvent that dissolves a binder to the ceramic sintered substrate and bonding the same. Good. Examples of the inorganic composition of the unsintered layer include Al ₂ O ₃ , MgO, ZrO ₂ , TiO ₂ , and Be.
Those containing at least one of O and BN are preferable.

When the electrode pattern is formed of a conductive paste composition containing cupric oxide as a main component, the electrode pattern is sintered in a nitrogen atmosphere after the binder removal step and the reduction step, and then the unsintered layer is formed. Get rid of. Further, a wiring pattern is formed on the uppermost layer with a Cu paste and fired in a nitrogen atmosphere.

[0026]

According to the present invention, an unsintered layer made of an inorganic composition which does not sinter at the firing temperature of glass / ceramic is formed on both sides or one side of the green sheet laminate and fired, whereby both sides of the laminate are fired. Or because the non-sintered inorganic material layer adheres to one side and prevents shrinkage in the plane direction,
The multilayer substrate is shrunk only in the thickness direction during firing and not shrunk in the plane direction, and is fired in a state where the green sheet laminate is warped through the unsintered layer and bonded to a flat board without irregularities. Warpage and unevenness can be prevented, and a desired substrate can be obtained by removing unnecessary unsintered inorganic composition after firing.

[0027]

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

(Embodiment 1) First, a first embodiment of a method for manufacturing a multilayer ceramic substrate will be described. Glass for substrate material
As the ceramic, a composition (MLS-19, manufactured by NEC Corporation) in which a weight ratio of alumina powder as a ceramic material to lead borosilicate glass powder was 50:50 was used. This glass-ceramic powder was used as an inorganic component, polyvinyl butyral was used as an organic binder, ヂ -n-butyl phthalate was used as a plasticizer, and a mixed solution (30 to 70 weight ratio) of toluene and isopropyl alcohol was used as a solvent to obtain a slurry.

Using this slurry, a green sheet having a thickness of about 200 μm was formed on an organic film by a doctor blade method. At this time, a system for continuously performing each step of drying, punching, and, if necessary, performing via hole processing from the film formation was used. An electrode pattern was formed on this green sheet using an Ag paste, and printing for filling the via holes was performed by a screen printing method. The Ag paste is 5 wt% of a glass frit (GA-9 glass powder manufactured by NEC Corporation, average particle size of 2.5 μm) for obtaining an adhesive strength to the Ag powder (average particle size of 1 μm).
% Was used as an inorganic component, ethyl cellulose as an organic binder was added together with a vehicle dissolved in terpineol, and the mixture was mixed with a three-stage roll so as to have an appropriate viscosity. In addition, the Ag paste for filling vias further contains the above-mentioned glass / ceramic powder as an inorganic component.
The test was carried out using 5% by weight.

Next, using only alumina (ALM-41 manufactured by Sumitomo Chemical Co., Ltd., average particle size: 1.9 μm) powder as the inorganic component, the same green sheet composition and the same method as the above-mentioned green sheet for a glass / ceramic substrate were used. Thus, a green sheet containing alumina as a main component to be an unsintered layer was produced. The thickness of this alumina green sheet is about 30
0 μm.

Thereafter, a predetermined number of the green sheets for the substrate on which the electrode patterns 2 and the via electrodes 3 are formed are stacked, and further thermocompression bonding is performed with the alumina green sheets superposed on both sides thereof, as shown in FIG. A green sheet laminate 1 was formed in which the electrode pattern 2 was formed in the inner layer and the unsintered layers 4 made of ceramic green sheets were laminated on both sides. The thermocompression bonding conditions were a temperature of 80 ° C. and a pressure of 200 kg / cm ² .

Next, a 96% alumina sintered substrate in which the warpage and unevenness of the substrate surface have been eliminated by polishing is prepared in advance as a floor plate 6 for firing the green sheet laminate 1, and the alumina green sheet is formed on the entire surface of the floor plate 6. The slurry used for this was printed at a thickness of 30 μm by a screen printing method to form a bonding alumina layer 5. After printing, the green sheet laminate 1 was brought into close contact with the bonding alumina layer 5 via the unsintered layer 4 in a state where the organic solvent in the bonding alumina layer 5 was not completely dried, and bonded by thermocompression bonding. The thermocompression bonding conditions are as follows: a temperature of 50 ° C. and a pressure of 50 kg / cm ^2.
Met. In a state where the green sheet laminate 1 is joined to the floor plate 6 via the unsintered layer 4 and the joining alumina layer 5,
The boundary between the alumina green sheet layer of the unsintered layer 4 and the bonding alumina layer 5 is not clear.

In this way, the green sheet laminate 1 is
It was baked in a state where it was joined to. The firing condition is firing at 900 ° C. for 1 hour in air by a belt furnace. (900
The holding time at ° C is about 12 minutes. The green sheet laminate 1 was turned into a multilayer substrate by firing, and an unsintered alumina layer was present on the surface and between the multilayer substrate and the floor plate 6. Therefore, ultrasonic cleaning was performed in a butyl acetate solvent. Then, the alumina layer was removed cleanly, and the multilayer substrate could be easily removed from the floor plate 6. The shrinkage of this multilayer substrate is 0.1% or less, no shrinkage in the plane direction has occurred,
There was no warpage. Further, the uppermost layer pattern was screen-printed on the multi-layer substrate using a silver / palladium paste, dried, and fired in the same manner as described above.

In the present embodiment, after the alumina slurry is printed on the floor plate 6 to form the bonding alumina layer 5, the green sheet laminate 1 and the floor plate 6 are thermocompression-bonded. Unsintered layer 4 instead of forming
Green sheet laminate 1 using an organic solvent or plasticizer that dissolves the binder in alumina green sheet
And the floor plate 6 may be joined.

Further, even if the above-mentioned slurry, organic solvent, plasticizer or the like is not used between the green sheet laminate 1 and the sole plate 6, the green sheet laminate 1 is Needless to say, the same effect can be obtained if a sufficient bonding strength can be obtained by directly thermocompression-bonding the same 6.

In this embodiment, Al ₂ O ₃ is used as the material of the unsintered layer 4.
Similar effects were obtained by using O, ZrO ₂ , TiO ₂ and BN.

(Example 2) A glass / ceramic green sheet as a substrate material had the same composition as in Example 1. After forming a via hole in a green sheet having a thickness of 200 μm, an electrode pattern was formed using a CuO paste and printing for filling the via hole was performed by a screen printing method. The conductor paste is CuO powder (average particle size 3μ).
m) glass frit (LS-0803 glass powder, manufactured by NEC Corporation, average particle size 2.5
μm) was added as an inorganic component, ethyl cellulose as an organic binder was added together with a vehicle dissolved in terpineol, and the mixture was mixed with a three-stage roll so as to have an appropriate viscosity. The CuO paste for filling vias was prepared by adding 15% by weight of the above glass / ceramic powder as an inorganic component.

Next, using only beryllium oxide powder (average particle size: 1 μm, manufactured by Kanto Chemical Co., Ltd.) as an inorganic component, using the same green sheet composition and the same method as the above-mentioned green sheet for a glass / ceramic substrate, A beryllium oxide green sheet was prepared as a binding layer. The thickness of this beryllium oxide green sheet is about 300 μm.

A predetermined number of the green sheets on which the electrode patterns are formed are stacked to form a green sheet laminate, and a beryllium oxide green sheet as an unsintered layer is laminated on both surfaces of the green sheets. In this state, the laminate was formed by thermocompression bonding. The thermocompression bonding conditions were a temperature of 80 ° C. and a pressure of 200 kg / cm ² . next,
96% without warpage and unevenness of the substrate surface by polishing in advance
An alumina sintered substrate was prepared as a floor plate for firing the green sheet laminate, and the green sheet laminate was adhered to the floor plate and joined by thermocompression bonding. The thermocompression bonding conditions were a temperature of 80 ° C. and a pressure of 100 kg / cm ² .

The green sheet laminate was fired in a state where the green sheet laminate was joined to a sole plate. The firing step was performed by the method described below. The first is a binder removal process. Green sheet used, organic binder of CuO paste,
Polyvinyl butyral and ethyl cellulose. Therefore, since the decomposition temperature in the air may be 500 ° C. or more, the laminate was degreased at a temperature of 600 ° C. Thereafter, the laminate was reduced in a 100% hydrogen gas atmosphere at 200 ° C. for 5 hours. When the Cu layer at this time was analyzed by X-ray diffraction, it was confirmed that the Cu layer was 100% Cu. In the next firing step, firing was performed in a mesh belt furnace at 900 ° C. in pure nitrogen. (The holding time at 900 ° C. is about 12 minutes.) The beryllium oxide layer on the surface of the multilayer substrate manufactured as described above was removed by ultrasonic cleaning as in Example 1, and the shrinkage was evaluated. The shrinkage of the multilayer substrate was 0.05% or less, and there was no warpage. Further, a commercially available Cu paste (manufactured by DuPont) is applied to the multilayer substrate.
The uppermost layer pattern was screen-printed by QP153), dried, and baked in nitrogen in the same manner as described above.

In the present embodiment, the green sheet laminate was directly bonded to the sole plate via the unsintered layer by thermocompression bonding. However, as in the method shown in the first embodiment, beryllium oxide was placed on the sole plate. It goes without saying that the same effect can be obtained by thermocompression bonding the green sheet laminate and the sole plate after printing the slurry or applying the organic solvent to the surface of the green sheet laminate.

In this embodiment, BeO was used as the material for the unsintered layer. However, other materials such as Al ₂ O ₃ , Mg
Similar effects were obtained by using O, ZrO ₂ , TiO ₂ and BN.

(Embodiment 3) Embodiment 1 up to the formation of an electrode pattern on a glass / ceramic green sheet of a substrate material
Was performed in the same manner as described above. Then, as shown in FIG. 2, a predetermined number of green sheets on which the electrode patterns 8 and the via electrodes 9 were formed were stacked and thermally pressed to form a green sheet laminate 7. The thermocompression bonding conditions were a temperature of 80 ° C. and a pressure of 200 kg / cm ² .

Next, magnesium oxide (manufactured by Kanto Kagaku) powder was used as an inorganic component, polyvinyl butyral was used as an organic binder, ヂ -n-butyl phthalate was used as a plasticizer, and a mixed solution of toluene and isopropyl alcohol (30 to 70) was used as a solvent. (Weight ratio) to obtain a slurry. This magnesium oxide slurry was repeatedly printed and dried on both surfaces of the green sheet laminate 7 by screen printing until the dried layer thickness became 150 μm to form a magnesium oxide unsintered layer 10.

Finally, the magnesium oxide slurry was printed on the surface of one of the unsintered layers 10, and the organic solvent was not completely dried.
% Alumina sintered substrate, and bonded by thermocompression bonding. The thermocompression bonding conditions were a temperature of 50 ° C. and a pressure of 50 kg / cm ² .

Next, the green sheet laminate 7
Was baked in a state where it was joined to the floor plate 11 via the unsintered layer 10, and after calcination, the magnesium oxide layer was removed. The shrinkage ratio of the fired multilayer substrate was 0.1% or less, no shrinkage in the planar direction occurred, and no warpage was observed.

In this embodiment, M is used as the unsintered material.
gO was used, but other Al ₂ O ₃ , BeO, Zr
Similar effects were obtained by using O ₂ , TiO ₂ , and BN.

[0048]

According to the method for manufacturing a multilayer ceramic substrate of the present invention, as described above, the unsintered layer made of an inorganic composition that does not sinter at the firing temperature of glass ceramic on both surfaces or one surface of the green sheet laminate. After bonding the green sheet laminated body on which the unsintered layer is formed, by thermocompression bonding to a floor plate made of a ceramic sintered substrate via the unsintered layer, and by firing, The non-sintered inorganic material layer adheres to both sides or one side to prevent shrinkage in the plane direction, so it shrinks only in the thickness direction during firing and does not shrink in the plane direction, and the green sheet laminate is not sintered By being fired in a state of being warped through layers and bonded on a floor plate having no unevenness, warping and unevenness of the multilayer substrate can be prevented, and unnecessary unsintered inorganic composition is removed after firing. It allows the desired substrate easily in the planar direction shrinkage without and without warpage or irregularities can sell easily.

The unsintered layer can be easily formed by laminating green sheets made of an inorganic composition or by applying and drying a paste composition containing the inorganic composition. .

Further, the electrode pattern is formed of a conductive paste composition containing cupric oxide as a main component, and after a binder removal step and a reduction step, a sintering step in a nitrogen atmosphere is performed to control the atmosphere. A multilayer ceramic substrate using a Cu electrode material that is inexpensive and has little price fluctuation can be manufactured by easy baking.

[Brief description of the drawings]

FIG. 1 is a sectional view of a laminated state at the time of sintering in a first embodiment of the present invention.

FIG. 2 is a sectional view of a laminated state at the time of sintering in a third embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Green sheet laminated body 2 Electrode pattern 3 Via electrode 4 Unsintered layer 5 Bonding layer 6 Laying board 7 Green sheet laminated body 8 Electrode pattern 9 Via electrode 10 Unsintered layer 11 Laminated board

Continued on the front page (72) Inventor Kazuhiro Miura 1006 Kazuma Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. ) Inventor Yoshifumi Nakamura 1006 Kazuma Kadoma, Kadoma City, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. (56) References JP-A-4-243978 (JP, A) JP-A 62-95896 (JP, A) JP-A Sho 62-145896 (JP, A) JP-A-6-283861 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) H05K 3/46

Claims (7)

(57) [Claims] 1. After laminating a desired number of green sheets made of glass / ceramic containing at least an organic binder and a plasticizer and having an electrode pattern formed by a conductive paste, the glass / ceramic is laminated on both sides or one side of the green sheet laminate. of forming a green layer composed of an inorganic composition which is not sintered at the firing temperature, the unsintered layer is formed <br/> green sheet laminate, ceramic sintering through the unsintered layer Bonded by thermocompression bonding on a board consisting of substrates
Thereafter, a firing process is performed, and thereafter , the unsintered layer is removed. 2. After laminating a desired number of green sheets made of glass / ceramic containing at least an organic binder and a plasticizer and having an electrode pattern formed by a conductive paste, the glass / ceramic is laminated on both sides or one side of the green sheet laminate. An unsintered layer made of an inorganic composition that does not sinter at the sintering temperature is formed, and the green sheet laminate on which the unsintered layer is formed is heat-bonded onto a base plate made of a ceramic sintered substrate via a bonding layer. A method for manufacturing a multilayer ceramic substrate, comprising: performing bonding after bonding by pressure bonding; and removing an unsintered layer and a bonding layer. 3. A method for laminating a desired number of green sheets comprising an electrode pattern formed by a conductor paste containing at least an organic binder and a plasticizer and made of glass ceramic containing cupric oxide as a main component. A green sheet laminate formed of an inorganic composition that does not sinter at the firing temperature of glass / ceramic is formed on both sides or one side of the body, and the green sheet laminate on which the unsintered layer is formed is referred to as the unsintered layer. After bonding by thermocompression bonding to a base plate made of a ceramic sintered substrate via air, heat treatment is performed in air at a temperature at which the organic binder inside the laminate decomposes and scatters, and then in a hydrogen or mixed gas atmosphere of hydrogen and nitrogen. A multi-layer ceramic substrate characterized by performing a reduction heat treatment in step (1), sintering the laminate in a nitrogen atmosphere, and then removing the unsintered layer. . 4. A method for laminating a desired number of green sheets comprising an electrode pattern formed of a conductor paste containing at least an organic binder and a plasticizer and made of glass ceramic containing cupric oxide as a main component. A green sheet laminate formed of an inorganic composition that does not sinter at the firing temperature of glass-ceramic is formed on both sides or one side of the body, and the green sheet laminate on which the unsintered layer has been formed is connected to the ceramic via a bonding layer. After bonding by thermocompression bonding to the base plate made of sintered substrate, the organic binder inside the laminate is decomposed and
Heat treatment in the air at the temperature at which it is scattered, then heat reduction treatment in an atmosphere of hydrogen or a mixed gas of hydrogen and nitrogen, and then sinter the laminate in a nitrogen atmosphere. A method for manufacturing a multilayer ceramic substrate, comprising: 5. The method according to claim 2 , wherein after removing the unsintered layer or the unsintered layer and the bonding layer, a wiring pattern is formed on the uppermost layer portion with a Cu paste and fired in a nitrogen atmosphere. 5. The method for manufacturing a multilayer ceramic substrate according to 4. 6. The method for manufacturing a multilayer ceramic substrate according to claim 1, wherein the thermocompression bonding is performed at least by heating and pressing. 7. The bonding layer is made of a glass ceramic containing at least an organic binder and a plasticizer, and is thermocompression-bonded without completely drying the organic solvent material in the bonding layer. Or the method of manufacturing a multilayer ceramic substrate according to 4.