JP2003124629A - Method for manufacturing glass ceramic substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for obtaining a glass ceramic substrate having high dimensional precision and a recessed part like a cavity by surely restraining sintering shrinkage of a glass ceramic green sheet laminate. SOLUTION: This method consists of a process wherein (I) a laminate 1' having the recessed part A is formed by laminating glass ceramic sheets, (II) a depth of 10-60% of the recessed part A is filled with inorganic composition 2' for restraint, an adhesive agent layer containing glass and solvent are interposed on both surfaces, and restraint green sheets 3' containing inorganic material which is hard to be sintered and organic binder are laminated, (III) restraint sheets 3 are held by sintering and the glass ceramic substrate 1 wherein the recessed part A is filled with inorganic material 2 for restraint is formed, and (IV) the restraint sheets 3 and the inorganic material 2 for restraint are eliminated from the substrate. Glass content of the adhesive agent layer is the amount which combines the restraint green sheet 3' with the laminate 1' in the case of baking and is eliminated together with the restraint sheet 3 from the glass ceramic substrate 1.

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 multi-layer glass ceramic substrate for mounting semiconductor LSIs, chip parts and the like and interconnecting them.

[0002]

2. Description of the Related Art In recent years, semiconductor LSIs, chip parts, etc. have been reduced in size and weight, and wiring boards for mounting them have also been desired to be reduced in size and weight. In response to such demands, the multilayer ceramic substrate in which internal electrodes and the like are arranged in the substrate enables high-density wiring required and can be thinned, and thus is regarded as important in the electronics industry today. There is.

As a multilayer ceramic substrate, an insulating substrate made of an alumina sintered body and having a wiring layer made of a refractory metal such as tungsten or molybdenum formed on the surface or inside thereof has been widely used.

On the other hand, in the recent age of advanced information technology, the frequency band used is shifting to higher frequencies. In a high-frequency wiring board that transmits such a high-frequency signal, in order to transmit a high-frequency signal at high speed, it is required that the conductor forming the wiring layer has a low resistance, and the insulating board also has a lower dielectric constant. Required.

However, conventional refractory metals such as tungsten (W) and molybdenum (Mo) have a large conductor resistance, a slow signal propagation speed, and it is difficult to propagate a signal in a high frequency region of 30 GHz or more. Instead of metals such as tungsten and molybdenum, copper (Cu), silver (Ag), gold (A
It is necessary to use low resistance metals such as u). However, the low melting point metal as described above has a low melting point,
Since it is necessary to fire at a relatively low temperature of about 1100 ° C, the wiring layer made of this low resistance metal could not be fired at the same time as alumina which requires high temperature firing.
Further, since the alumina substrate has a high dielectric constant, it was difficult to say that it is suitable for a high frequency circuit substrate.

Therefore, recently, attention has been paid to the use of glass ceramics obtained by firing a mixture of glass and ceramics (inorganic filler) as an insulating substrate. That is, since glass ceramics has a low dielectric constant, it is suitable as an insulating substrate for high frequencies, and since glass ceramics can be fired at a low temperature of 800 to 1100 ° C, a low resistance metal such as copper, silver, or gold is used as a wiring layer. There is an advantage that it can be used as.

The multi-layer glass ceramic substrate is made into a slurry by adding an organic binder, a plasticizer, a solvent and the like to a mixture of glass and an inorganic filler, and after forming a glass ceramic green sheet with a doctor blade or the like, copper,
A conductor pattern containing a powder of a low resistance metal such as silver or gold is printed to form a conductor pattern on the green sheet, and then a plurality of green sheets are laminated to form a conductor pattern.
It is obtained by firing at a temperature of 0 to 1100 ° C.

However, the multilayer glass ceramic substrate is
There is a problem that shrinkage occurs due to sintering in the firing process. The degree of such shrinkage is not uniform, and the shrinkage rate and the shrinkage direction differ depending on the inorganic material for the substrate used, the green sheet composition, the variation in the particle size of the raw material powder, the conductor pattern, the internal electrode material, and the like. This causes some problems in the production of multilayer glass ceramic substrates.

First, when manufacturing a screen printing plate for printing internal electrodes, the size of the screen printing plate must be determined by back-calculating from the shrinkage ratio of the substrate. Since it is not constant, the screen plate must be remade for each manufacturing lot of the substrate, which is uneconomical and impractical. Further, in the multilayer glass ceramic substrate produced by the green sheet laminating method as described above, since the shrinkage rates in the longitudinal direction and the lateral direction in the laminating plane differ depending on the film forming direction of the green sheet, it is possible to produce the multilayer glass ceramic substrate. It will be even more difficult.

On the other hand, if an electrode having an unnecessarily large area is formed to allow the shrinkage error, high-density wiring cannot be performed.

In order to reduce these shrinkage changes,
Investigate the tendency of the shrinkage rate of the board due to the circuit design, manage the board material and the green sheet composition in the manufacturing process,
It is necessary to adequately control the stacking conditions such as variations in powder particle size, press pressure and temperature. However, it is generally said that a shrinkage error of about ± 0.5% exists.

This is a problem that is common to ceramics, glass ceramics, and the like that involve sintering, regardless of the multilayer glass-ceramic substrate. In order to solve such a problem, JP-A-4-243978 and JP-A-5-2886
In Japanese Patent Laid-Open No. 7-102666 and Japanese Patent Laid-Open No. 5-102666, the following (1)
A method of manufacturing a substrate including the steps (4) to (4) has been proposed.

(1) A desired number of glass ceramic green sheets containing a glass ceramic component and an organic component such as a binder and a plasticizer and having conductor patterns formed thereon are laminated, and (2) the obtained glass ceramic green sheet. A constrained green sheet containing an inorganic material that does not sinter at the firing temperature of the glass ceramic component and an organic component such as a binder or a plasticizer is laminated on both surfaces or one surface of the laminated body of (3) these glass ceramic green sheets. By heating the laminated body of and the restraint green sea,
First, the organic component is removed and then fired to form a glass ceramic substrate and a constraining sheet, respectively. (4) Finally, the constraining sheet is removed from the glass ceramic substrate.

According to this method, since the constraining green sheet constrains the shrinkage of the glass-ceramic green sheet during firing, shrinkage occurs only in the thickness direction of the laminated body, and in the longitudinal and lateral directions of the laminated surface. It is considered that the shrinkage does not occur and the dimensional accuracy of the glass ceramic substrate is improved.

Further, in a glass ceramic substrate having a recess such as a cavity, in order to solve the above problems, for example, Japanese Patent Laid-Open No. 11-177238 proposes a method of manufacturing a glass ceramic substrate including the following steps. There is.

This is a method for producing a glass-ceramic multilayer substrate having a cavity portion produced by a low temperature sintering process by laminating glass-ceramic green sheets, wherein the cavity of the glass-ceramic green sheet laminate is produced. Filling the inside of the part with a paste mainly containing an inorganic component having a higher sintering temperature than the glass ceramics, and mainly containing an inorganic component having a higher sintering temperature than the glass ceramics on the upper and lower surfaces of the green sheet laminate. And a step of arranging the molded body on both upper and lower surfaces of the green sheet laminate, and then performing firing while applying pressure to the upper and lower surfaces of the green sheet laminate.

According to this method, the inside of the recess is filled with a paste mainly containing an inorganic component having a sintering temperature higher than that of the glass ceramics, and the solid content ratio of the paste is controlled, so that the glass containing the cavity during firing is filled. A uniform pressing force can be applied to the entire surface of the ceramic laminate, deformation and cracks around the cavity can be suppressed, and horizontal contraction during sintering can be suppressed.

[0018]

[Problems to be Solved by the Invention] The above (1) to (4)
In the method including the step of, the binding between the glass ceramic green sheet and the constraining green sheet is performed by an organic component such as a binder contained in these green sheets. However, in the firing process of (3),
After the organic components such as the binder and plasticizer are decomposed and volatilized, the powder in the constrained green sheet and glass ceramic
The powders in the green sheets are only in intimate contact with each other, and a weak bond due to van der Waals force is acting between the sheets.

Although such a weak bond has an advantage that the constraining sheet can be easily removed in the step (4), the constraining green sheet is removed from the glass ceramic green sheet laminate in the firing step (3). There is a risk of inadvertent peeling due to differences in thermal expansion.

If the constrained green sheet peels off during firing, it becomes impossible to prevent the sintering shrinkage of the glass ceramic green sheet. Further, even if the constrained green sheet is partly peeled off, the glass ceramic substrate is deformed because shrinkage occurs in the part.

Further, since the glass-ceramic / green sheet laminate and the constraining green sheet have a small bonding force,
Depending on the adhesion state of them before firing and the permeability of the glass component in the glass-ceramic green sheet into the constrained green sheet depending on the type of the glass-ceramic component, the binding force thereof is likely to be uneven. If the binding force is uneven, the force for restraining the sintering shrinkage of the glass ceramic is also uneven, and uneven shrinkage occurs, and the glass ceramic substrate is warped or deformed. As a result, there is a problem that a substrate with high dimensional accuracy cannot be obtained.

Further, in the method disclosed in Japanese Patent Application Laid-Open No. 11-177238, since a paste mainly containing an inorganic component having a sintering temperature higher than that of glass ceramics is filled in the concave portion, the same glass as the constraining sheet is used. There is a problem that the bonding force with the ceramics is likely to be uneven, and as a result, the cavity or the like is warped and deformed.

When firing a laminate of the glass-ceramic green sheet laminate in which the paste is filled in the recess and the molded body that is the constraining green sheet, the glass-ceramic green sheet laminate is 50 in the thickness direction. In contrast to shrinking to a thickness of ~ 60%, the fired body of the paste mainly containing an inorganic component having a higher sintering temperature than glass ceramics does not shrink, so that the fired body of the paste filled in the recesses during firing is It comes to project from the recess. As a result, the fired body of the paste mainly containing an inorganic component having a sintering temperature higher than that of the protruding glass ceramics pushes up the constraining green sheet in the upper part of the recess and the peripheral part of the recess, and becomes a restrictive green sheet in the peripheral part of the recess. There is a problem that peeling occurs between the green sheet laminated body of glass ceramics and deformation occurs around the cavity.

[0024]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have made (I) a glass component contained between the constrained green sheet and the glass ceramic green sheet. By interposing an adhesive layer,
Since the glass component acts as a binding material that binds the glass ceramic green sheet and the constraining green sheet in the firing process, the binding force between them is increased and the constraining green sheet can be prevented from peeling, (II) The content of the glass component in the adhesive layer is the amount removed from the glass ceramic substrate together with the constraining sheet after firing, and as a result, (III) the constraining green sheet ensures that the glass ceramic / green sheet laminate shrinks. It is possible to obtain a glass-ceramic substrate that is suppressed and has high dimensional accuracy. Further, (IV) an inorganic composition for constraining having the same composition as the constraining green sheet is formed in the recesses such as cavities before the constraining green sheets are laminated. By filling the bottom of the base with a height of 10 to 60% of the depth of the recess, the recess is restrained and further Suppressing deformation in the recess and the periphery thereof due to the difference in the thickness direction of shrinkage of the glass ceramic green sheet laminate with constraining inorganic composition,
The present invention has been completed by discovering a new fact that a glass ceramic substrate having a dimensional accuracy can be obtained even in a glass ceramic substrate having a concave portion.

That is, the method for producing a glass ceramic substrate of the present invention comprises: (i) a plurality of glass ceramic green sheets containing an organic binder and having a conductor pattern formed on the surface and glass ceramic green sheets having through holes. Step (ii) of stacking sheets to prepare a glass-ceramic / green-sheet laminate having a recessed portion, from the bottom surface of the glass-ceramic / green-sheet laminated body containing a constraining inorganic composition containing a hardly-sinterable inorganic material in the recessed portion. While filling to a height of 10 to 60% with respect to the depth of the recess,
A step of laminating constraining green sheets containing a hardly-sinterable inorganic material and an organic binder on both surfaces of the glass ceramic green sheet laminate with an adhesive layer containing glass and a solvent interposed therebetween, (iii) A step of removing the organic component from the laminated body of the constrained green sheet and the glass-ceramic / green-sheet laminated body, and then firing to hold the constrained sheet and produce a glass-ceramic substrate in which recesses are filled with the constraining inorganic material; (Iv) a step of removing the constraining sheet and the constraining inorganic substance from the glass ceramic substrate, and (v) the glass content of the adhesive layer is such that the constraining green sheet becomes the glass ceramic green sheet during firing. It is the amount removed from the glass ceramic substrate together with the restraint sheet after binding and firing. That.

In the present invention, the softening point of the glass contained in the adhesive layer is preferably below the firing temperature of the glass-ceramic / green sheet laminate. As a result, the glass in the adhesive layer is softened in the firing step and the bonding strength is increased.

The softening point of the glass contained in the adhesive layer is preferably higher than the volatilization temperature of the organic component. When the softening point of the glass is lower than the volatilization temperature of the organic component, the removal path for passing the decomposed / volatilized organic component may be blocked by the softened glass.

The glass content in the adhesive layer is preferably 5 to 50% by weight of the components of the adhesive layer. Usually, this range does not impair the adhesion between the glass ceramic green sheet and the constraining green sheet during lamination, and is combined with the glass ceramic green sheet during firing and is removed from the glass ceramic substrate together with the constraining sheet after firing. Become. If the amount is less than 5% by weight, the amount of glass acting as a binder during firing is small and the binding between the constraining sheet and the glass ceramic green sheet becomes insufficient. If the amount is more than 50% by weight, the amount of glass is large, so that the area where the constrained green sheet and the glass ceramic green sheet adhere to each other during lamination becomes small, and the adhesion before firing may deteriorate. Further, when the constraining sheet is removed after firing, it is difficult to remove the constraining sheet because a strong glass layer is formed on the glass ceramic substrate.
Although the glass content varies depending on the type of glass used, it is preferably about 5 to 50% by weight.

Filling the concave portion such as the cavity with the restraining inorganic composition is 10 to 60% of the depth of the concave portion from the bottom surface of the concave portion.
It is better to fill at the height of. When the height from the bottom surface of the recess is more than 60% with respect to the depth of the recess, the restraining inorganic composition filled in the recess during firing will protrude from the recess, and the protruding restraining inorganic composition is The constraining green sheets in the upper part and the peripheral part are pushed up, and peeling occurs between the constraining green sheet around the recess and the glass-ceramic / green-sheet laminate, which causes deformation around the recess. . Further, if the height is less than 10% of the depth of the recess from the bottom of the recess, the restraint property is lowered and good dimensional accuracy cannot be obtained.

According to the present invention, even when the glass ceramic substrate has a recess such as a cavity, the constraining inorganic composition is filled to a height of 10 to 60% from the bottom of the recess to the depth of the recess. After that, the constraining green sheets are laminated to constrain the shrinkage of the glass-ceramic / green-sheet laminate, so that the deformation of the recesses after firing can be almost eliminated, and the dimensional accuracy of the glass-ceramic substrate having the recesses can be improved. You can get a high price.

The constraining inorganic composition to be filled in the recess may be in the form of paste or powder, and may be various depending on the required precision, shape, size, etc. of the glass ceramic substrate. It may be used in the form of.

[0032]

BEST MODE FOR CARRYING OUT THE INVENTION The method for producing a glass ceramic substrate of the present invention will be described in detail below.

The glass-ceramic green sheet in the present invention is a mixture of glass powder, filler powder (ceramic powder), organic binder, plasticizer, organic solvent and the like.

As the glass component, for example, SiO₂-B₂
O₃System, SiO₂-B₂O₃-Al₂O₃System, SiO₂-B₂O
₃-Al₂O₃-MO system (however, M is Ca, Sr, Mg,
Ba or Zn), SiO₂-Al₂O₃-M¹O-
M²O type (however, M¹And M ²Are the same or different and are C
a, Sr, Mg, Ba or Zn), SiO₂−
B₂O₃-Al₂O₃-M¹OM²O type (however, M¹and
M²Is the same as above), SiO₂-B₂O₃-M³ ₂O system
(However, M³Represents Li, Na or K), SiO₂−
B₂O₃-Al₂O₃-M³ ₂O type (however, M³Is the same as above
Pb-based glass, Bi-based glass, and the like.
It

The filler may be, for example, Al.
_At least one selected from ₂ O ₃ , SiO ₂ , composite oxide of ZrO ₂ and alkaline earth metal oxide, composite oxide of TiO ₂ and alkaline earth metal oxide, Al ₂ O ₃ and SiO _2. Examples thereof include complex oxides containing (for example, spinel, mullite, cordierite).

The mixing ratio of the above glass and the filler is a ratio used in a usual glass ceramic substrate material, and it is preferably 40:60 to 99: 1 by weight.

As the organic binder to be blended with the glass ceramic green sheet, those conventionally used for ceramic green sheets can be used.
For example, acrylics (homopolymers or copolymers of acrylic acid, methacrylic acid or their esters, specifically acrylic acid ester copolymers, methacrylic acid ester copolymers, acrylic acid ester-methacrylic acid ester copolymers Etc.), polyvinyl butyral type, polyvinyl alcohol type, acryl-styrene type, polypropylene carbonate type, cellulose type homopolymers or copolymers.

The glass-ceramic green sheet is obtained by adding a predetermined amount of a plasticizer and a solvent (organic solvent, water, etc.) to the above-mentioned glass powder, filler powder and organic binder to obtain a slurry, which is then doctor blade. , Rolling, calender roll, die press, etc., thickness about 50-500μ
It is obtained by molding into m.

Further, in the obtained glass ceramic green sheet, through holes having a predetermined shape and size for forming recesses such as cavities are formed at predetermined positions by punching or the like, if necessary.

To form a conductor pattern on the surface of the glass ceramic green sheet, for example, a paste of conductor material powder is printed by a screen printing method or a gravure printing method, or a metal foil having a predetermined pattern shape is transferred. And the like. As the conductor material, for example, Au, Ag, Cu, Pd (palladium), P
One or two or more kinds of t (platinum) and the like can be mentioned, and in the case of two or more kinds, they may be in any form such as mixing, alloying, coating and the like.

The conductor pattern on the surface also includes a portion where a through conductor such as a via conductor or a through-hole conductor for connecting conductor patterns between upper and lower layers is exposed on the surface. These through conductors are formed by means of embedding a paste (conductor paste) of conductive material powder in a through hole formed in a glass ceramic green sheet by punching or the like by printing.

For lamination of glass ceramic green sheets, a method of applying heat and pressure to the stacked green sheets to perform thermocompression bonding, or applying an adhesive agent composed of an organic binder, a plasticizer, a solvent, etc. between the sheets and performing thermocompression bonding. It is possible to adopt a method of doing so.

The restraint green sheet in the present invention is obtained by molding a slurry obtained by adding an organic binder, a plasticizer, a solvent and the like to an inorganic component made of a hardly-sinterable inorganic material. The hardly-sinterable inorganic material includes at least one selected from Al ₂ O ₃ and SiO _2, but is not limited to these.

Further, the constraining green sheet may contain the same glass component as that of the adhesive layer to enhance the binding force between the constraining green sheet and the glass ceramic green sheet. In that case, the amount of the glass component is preferably an amount that does not substantially shrink the constrained green sheet in the laminated surface during firing.

The composition of the constraining green sheet as described above is the same as the composition of the constraining inorganic composition with which the recesses are filled.

The constrained green sheet can be obtained by molding using an organic binder, a plasticizer, a solvent and the like in the same manner as in the production of the glass ceramic green sheet. As the organic binder, the plasticizer and the solvent, the same materials as those used for the glass ceramic green sheet can be used. Here, the plasticizer is added in order to impart flexibility to the constrained green sheet and enhance the adhesiveness with the glass ceramic green sheet during lamination.

The restraint inorganic composition is the same as the restraint green sheet, to which an organic binder, a plasticizer, a solvent, etc. are added in order to form a paste or to have adhesiveness. You may use. As the organic binder, for example, polyvinyl alcohol may be added in an amount of about 5% by weight with respect to the hardly-sinterable inorganic material and the glass, but not limited to this, an ethyl cellulose-based or nitrocellulose-based organic component, methyl acrylate, polyacrylate You may add methyl acrylate, methyl methacrylate, etc. about 5 to 15 weight%. Further, as the organic solvent, toluene or various alcohols may be added in an amount of about 20 to 40% by weight.

As the organic binder, the plasticizer and the solvent added to the constraining green sheet and the constraining inorganic composition, the same materials as those used for the glass ceramic green sheet can be used in addition to the above. Here, the plasticizer may be added to impart flexibility to the constrained inorganic composition layer and enhance adhesion to the glass ceramic green sheet during lamination.

The thickness of the constraining green sheets laminated on both sides of the glass ceramic green sheet laminate is preferably 10% or more with respect to the thickness of the glass ceramic green sheet laminate on only one side. If the thickness is smaller than the above range, the constraining property of the constraining green sheet may deteriorate. Considering that the organic components are easily volatilized and the restraint sheet is easily removed from the glass ceramic substrate, the restraint green sheet has a thickness of about 200% or less of the thickness of the glass ceramic / green sheet laminate. It should be Further, the constraining sheet to be laminated may be a single sheet, or a plurality of sheets may be laminated so as to have a predetermined thickness.

The adhesive for forming the adhesive layer is glass powder,
A mixture of organic solvents and the like is used. Further, an organic binder component may be contained to increase the binding force between the green sheets before firing, or the viscosity may be adjusted to be easy to apply. Further, a dispersant or the like may be added to improve the dispersibility of the glass in the adhesive.

The glass in the adhesive agent is not particularly limited, and the same glass as the glass compounded in the above-mentioned glass ceramic green sheet can be used. Also, the glass in the adhesive is glass ceramic
It may have the same composition as the glass in the green sheet, or may have a different composition.

The softening point of the glass in the adhesive is preferably lower than the firing temperature of the glass ceramic / green sheet laminate and higher than the decomposition / volatilization temperature of the organic component in the green sheet. Specifically, the softening point of glass in the adhesive is preferably about 450 to 1100 ° C. If the softening point of the glass is lower than 450 ° C, the removal of the organic component from the glass-ceramic / green sheet laminate will block the removal route of the organic component decomposed and volatilized by the softened glass, thus completely removing the organic component. May not be removed. On the other hand, when the softening point of the glass exceeds 1100 ° C., there is a possibility that the glass does not act as a binder to the green sheet under the usual firing conditions of the glass ceramic green sheet.

The particle size of glass in the adhesive is preferably 10 μm or less. If it is larger than this, glass particles may bite into the conductor pattern on the glass-ceramic / green sheet laminate during lamination of the green sheets, which may increase the surface roughness of the conductor after firing or cause defects in the conductor. This is because there is a risk of doing so. In addition, the restraint green sheet is softer than the conductor pattern,
There is no such limitation when the glass cuts into the restraint green sheet.

The solvent in the adhesive is not particularly limited as long as it uniformly disperses the glass and does not hinder the bonding between the green sheets. Also, a plurality of solvents can be mixed and used. It is preferable to use a material that imparts flexibility to the green sheets, swells or dissolves the surfaces of the green sheets to enhance the bonding force between the green sheets. Specifically, diethylene glycol monobutyl ether acetate (BCA), di-n-butyl phthalate (DBP), di-2-ethylhexyl phthalate (di-sec-octyl phthalat).
e: DOP), terpineol, toluene, butyl acetate, ethyl acetate, etc., but different solvents may be used as appropriate solvents depending on the green sheet.

In order to laminate the formed constrained green sheets on both sides of the glass-ceramic / green-sheet laminate, a method of forming an adhesive layer between the sheets and press-bonding is adopted. For example, there is a method in which an adhesive agent is applied to a constrained green sheet by screen printing, laminated on a glass ceramic / green sheet laminate, and thermocompression bonded.

When the constraining green sheet is laminated on the glass-ceramic / green-sheet laminate, the constraining inorganic composition is provided in the recess A of the glass-ceramic / green-sheet laminate 1'as shown in the sectional view of FIG. After filling the object 2 ′ with a height of 10 to 60% from the bottom to the depth of the recess A and drying the organic solvent in the restraining inorganic composition 2 ′ to some extent,
The constraining green sheets 3'are arranged on both sides of this with an adhesive layer (not shown) interposed therebetween, and are laminated under pressure of, for example, about 5 to 20 MPa.

After filling the concave portion A with the constraining inorganic composition 2'and laminating the constraining green sheet 3 ', the organic components are removed and baked. The organic components are removed by heating the laminated body in the temperature range of 100 to 800 ° C. to decompose and volatilize the organic components. Although the firing temperature varies depending on the glass ceramic composition, it is usually in the range of about 800 to 1100 ° C. Firing is usually performed in the atmosphere, but C is used as the conductor material.
When u is used, organic components are removed in a nitrogen atmosphere containing water vapor at 100 to 700 ° C., and then firing is performed in a nitrogen atmosphere.

Further, at the time of removing the organic component and at the time of firing, in order to prevent the deformation of the constraining inorganic composition 2'and prevent the warp of the laminate, a weight is placed on the upper surface of the laminate. You may apply a load. A load of about 50 Pa to 1 MPa is suitable for the weight. If the load is less than 50 Pa, the effect of suppressing the deformation of the constraining inorganic composition 2 ′ and the effect of suppressing the warp of the laminate may be insufficient. Also, if the load exceeds 1 MPa, the weight to be used will be large, so that it will not be able to enter the firing furnace, and even if it enters the firing furnace, the weight will be large and the heat capacity will be insufficient, resulting in insufficient firing. It may cause problems such as being unable to do so.

As for this weight, the load becomes non-uniform due to deformation or melting during firing of the glass ceramic substrate,
A heat-resistant porous material that does not hinder the volatilization of decomposed organic components is suitable. Specific examples include refractory materials such as ceramics and high melting point metals. Further, a porous weight may be placed on the upper surface of the laminate and a non-porous weight may be placed on it.

After firing in this way, the constraining inorganic composition 2 formed by firing the constraining inorganic composition 2'in the recess A of the glass ceramic substrate 1 as shown in the sectional view of FIG. A glass-ceramic substrate 1 having both sides filled with the binding sheet 3 and laminated with the binding sheets 3 on both sides, and the binding sheet 3 around the recess A being not separated from the glass-ceramic substrate 1 is obtained. To be

After the glass ceramic substrate 1 holding the constraining sheets 3 on both sides is obtained by firing, the constraining sheet 3 and the constraining inorganic substance 2 are removed. Here, the adhesive layer can be removed together with the constraining sheet 3. The removing method is not particularly limited as long as it can remove the constraining sheet 3 bonded to the surface of the glass ceramic substrate 1. For example, ultrasonic cleaning, polishing, water jet, chemical blasting,
Sand blast, wet blast (a method of spraying abrasive grains and water by air pressure) and the like can be mentioned.

The obtained multilayer glass ceramic substrate 1 is
Since the shrinkage during firing is suppressed only in the thickness direction by the constraining green sheet 3 ', it is possible to suppress the shrinkage in the stacking plane to about 0.5% or less, and further, the glass ceramic green sheet stack 1 Since the'constrained green sheet 3'is uniformly and surely bonded over the entire surface, it is possible to prevent warping or deformation due to partial peeling of the constrained green sheet 3 '. Furthermore, since the concave portion A of the glass-ceramic / green sheet laminate 1'is filled with the restraining inorganic composition 2'and its deformation is suppressed, the concave portion A also has high dimensional accuracy, and the concave portion A and its surroundings are high. It is possible to obtain the glass ceramic substrate 1 which is not deformed.

[0063]

EXAMPLES The method of the present invention will be described in detail below with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples.

Example 1 As a glass ceramic component, SiO ₂ —Al ₂ O ₃ —MgO—B ₂ O ₃ —ZnO type glass powder 60% by weight, CaZrO ₃ powder 20% by weight, SrT.
17% by weight of iO ₃ powder and 3% by weight of Al ₂ O ₃ powder were used. To 100 parts by weight of this glass-ceramic component, 12 parts by weight of an acrylic resin as an organic binder, 6 parts by weight of a phthalic acid-based plasticizer and 30 parts by weight of toluene as a solvent were added and mixed by a ball mill method to obtain a slurry. Using this slurry, a glass ceramic green sheet having a thickness of 300 μm was formed by the doctor blade method.

Then, a conductor pattern was formed on this green sheet by screen printing using a silver-palladium paste. As the conductor paste, ₂ parts by weight of Al ₂ O ₃ powder and 2 parts by weight of glass powder having the same composition as the above-mentioned glass with respect to 100 parts by weight of alloy powder (average particle size 1.0 μm) in which Ag: Pd is 85:15 in weight ratio are used. By weight, a predetermined amount of ethyl cellulose resin and terpineol were further added as vehicle components, and the mixture was mixed with a three-roll so as to have an appropriate viscosity.

On the other hand, using Al ₂ O ₃ powder as an inorganic component, a slurry was prepared in the same manner as the glass ceramic green sheet, and then molded to obtain a constrained green sheet having a thickness of 250 μm.

Further, a non-sinterable inorganic material having the same composition as the constraining green sheet was used as the constraining inorganic composition, and 30% by weight of a vehicle in which an ethyl cellulose resin was dissolved in alcohol was added and kneaded.

The adhesive is SiO ₂ --Al ₂ having a softening point of 720 ° C.
_{O 3 -MgO-B 2 O 3} -ZnO based glass powder 25 wt% and DBP39 wt%, BCA31.2 wt%, was a mixture of 4.8 wt% acrylic binder.

A predetermined number of glass ceramic green sheets are stacked together with the glass ceramic green sheets having a conductive pattern formed on the surface thereof by forming a through hole to be a recess at a predetermined position using a punching die or a punching machine. Glass-ceramics with a concave portion having a vertical dimension of 200 mm and a horizontal dimension of 200 mm in the laminated surface by pressure bonding at a temperature of 55 ° C and a pressure of 20 MPa.
A green sheet laminate was obtained. Then, the above-mentioned constraining inorganic composition was filled in the recesses by a screen printing method to a height of 50% with respect to the depth of the recesses, and a constraining green sheet coated with an adhesive agent was superposed on both surfaces thereof, Temperature 55
A laminate was obtained by pressure bonding at a temperature of 20 ° C. and a pressure of 20 MPa.

The obtained laminated body was placed on an alumina setter, a weight was placed on the alumina setter, and the organic component was removed by heating at 500 ° C. for 2 hours in the atmosphere while applying a load of about 0.5 MPa. Calcination was performed for 1 hour. After firing, the restraining sheet adhered to both surfaces of the glass ceramic substrate without the restraining inorganic substance protruding from the recess. In this state, the binding sheet was not peeled off even if tapped lightly.

The restraint sheet adhered to the surface of the glass ceramic substrate could be mostly removed by scraping it off together with the restraining inorganic substance in the recess, but it remained thin on the surface of the glass ceramic substrate. This remaining restraint sheet
A mixture of spherical Al ₂ O ₃ fine powder and water was removed by a wet blast method in which high-pressure air pressure was used for projection. The surface of the glass ceramic substrate after removing the constraining sheet was a smooth surface having a surface roughness (arithmetic mean roughness) Ra of 1 μm or less, and there was no problem with the solder wettability of the conductor.

Further, the shrinkage in the laminated surface of the obtained glass ceramic substrate was 0.5% or less, and the substrate was not warped or deformed.

<Examples 2 and 3> The softening point is 600.
A glass-ceramic substrate was obtained in the same manner as in Example 1 except that the adhesive was prepared by using glass at 70 ° C and 700 ° C, respectively.

Comparative Example 1 A glass ceramic substrate was obtained in the same manner as in Example 1 except that an adhesive agent containing no glass was prepared.

<Comparative Example 2> A glass ceramic substrate was obtained in the same manner as in Example 1 except that an adhesive was prepared using glass having a softening point of 920 ° C.

<Comparative Example 3> A glass ceramic substrate was obtained in the same manner as in Example 1 except that an adhesive was prepared using glass having a softening point of 400 ° C.

As a result, the glass-ceramic substrates obtained in Examples 2 and 3 had a shrinkage within the lamination plane of 0.5% or less (that is, a shrinkage ratio of 99.5% or more) as in Example 1. No warp or deformation was observed.

On the other hand, in the glass ceramic substrates obtained in Comparative Examples 1 and 2, the adhesive layer used does not contain glass, or contains glass having a softening point higher than the firing temperature. As a result, the constrained green sheets were easily peeled off from the glass ceramic substrate after firing. Also, because the binding force between the glass ceramic green sheet and the restraint green sheet is weak,
The shrinkage ratio of the glass ceramic substrate in the laminating plane is about 85%, or the glass ceramic substrate is largely deformed because only part of the substrate is bonded to the constraining sheet.

On the other hand, in Comparative Example 3, since the softening point of the glass contained in the adhesive layer was low, the organic component was not completely removed, and therefore the shrinkage in the laminated surface of the glass ceramic substrate was 0.5% or less. Although it was good, the color tone of the glass ceramic substrate became gray.

<Example 4 and Example 5> Example 1 except that the recessed inorganic composition was filled in the recesses by screen printing at a height of 10% and 60% of the depth of the recesses.
A glass ceramic substrate was obtained in the same manner as in.

<Comparative Example 4 and Comparative Example 5> Example 1 except that the recessed inorganic composition was filled in the recesses by screen printing at a height of 5% and 70% of the depth of the recesses.
A glass ceramic substrate was obtained in the same manner as in.

Table 1 shows the warp of the obtained glass ceramic substrate and the warp of the bottom surface of the recess.

[0083]

[Table 1]

From Table 1, the glass ceramic substrates obtained by filling the filling heights of Examples 1, 4 and 5 with the constraining inorganic composition, the warpage of the substrate and the bottom surface of the recess during firing were suppressed. You can see that In addition, no deformation was observed in the recess and its surroundings. On the other hand, in the glass ceramic substrate obtained by filling the filling height (5%) of the restraining inorganic composition in Comparative Example 4, the inside of the concave portion was not sufficiently restrained, and the concave portion was largely warped. Further, in the glass ceramic substrate obtained by filling the constraining inorganic composition to the filling height (70%) of Comparative Example 5, the constraining inorganic composition protruded from the recess, and the constraining green sheet and glass around the recess were formed. Since peeling occurred between the ceramic substrate and the ceramic substrate, the warp of the bottom surface of the recess and the warp of the glass ceramic substrate were large. In addition, deformation was generated around the recess.

<Examples 6 to 9> As the glass ceramic component, 70 wt% of SiO ₂ -MgO-CaO-Al ₂ O ₃ based glass powder and 30 wt% of Al ₂ O ₃ powder were used. To 100 parts by weight of this glass-ceramic component, 9.0 parts by weight of an acrylic resin as an organic binder, 4.5 parts by weight of a phthalic acid-based plasticizer and 30 parts by weight of toluene as a solvent were added and mixed by a ball mill method to obtain a slurry. Using this slurry, a glass ceramic green sheet having a thickness of 300 μm was formed by the doctor blade method.

Then, Example 1 was placed on this green sheet.
The same silver-palladium paste was used to form a conductor pattern by screen printing.

On the other hand, Al ₂ O ₃ powder was used as an inorganic component to prepare a slurry in the same manner as the glass ceramic green sheet, and then the slurry was molded to obtain a constrained green sheet having a thickness of 250 μm.

Further, as the constraining inorganic composition, a non-sinterable inorganic material having the same composition as the constraining green sheet and glass were used, and 30% by weight of a vehicle in which an ethyl cellulose resin was dissolved in alcohol was added and kneaded to obtain a composition. .

The adhesive is SiO ₂ -M having a softening point of 720 ° C.
gO-CaO-Al ₂ O ₃ based glass powder and DBP, BC
It was produced using a mixture of A and an acrylic binder in the proportions shown in Table 1, respectively.

A through hole having a predetermined shape and size is formed at a predetermined position of a predetermined glass ceramic green sheet, and a predetermined number of the glass ceramic green sheets having a conductor pattern formed on the surface are stacked, and the temperature is 55 ° C. Pressure 20
By pressure bonding with MPa, a glass-ceramic green sheet laminate having recesses each having a dimension of 200 mm in the longitudinal direction and 200 mm in the transverse direction is obtained, and the above-mentioned inorganic composition for restraint is placed in the recesses. Filled from the bottom to a height of 50% with respect to the depth of the recess, and superposing a constraining green sheet on both surfaces of which the adhesive layer is formed by applying by screen printing on the surface to be adhered to the laminated body, and the temperature 55 ℃, pressure 20MP
A laminate was obtained by pressing with a.

The obtained laminate was placed on an alumina setter, a weight was placed on the setter, and a load of about 0.5 MPa was applied to the laminate for heating at 500 ° C. for 2 hours in the atmosphere to remove organic components. Calcination was performed for 1 hour. Next, the restraint sheet and the restraining inorganic substance attached to the surface of the glass ceramic substrate were removed. The surface of the obtained glass ceramic substrate is
The surface roughness (arithmetic mean roughness) Ra was a smooth surface of 1 μm or less, and there was no problem with the solder wettability of the conductor.

Table 2 also shows the shrinkage ratio of the obtained glass ceramic substrate in the laminated plane. No warp or deformation was observed in the glass ceramic substrate.

[0093]

[Table 2]

It can be seen from Table 2 that the glass ceramic substrates obtained by using the adhesives of Examples 6 to 9 have high dimensional accuracy because shrinkage during firing is suppressed. In addition, the deformation of the recess was not recognized.

[0095]

EFFECTS OF THE INVENTION According to the present invention, a constraining inorganic composition containing a hardly sinterable inorganic material, which is bonded to the glass-ceramic / green-sheet laminate in the recess and is not substantially fired at the time of firing. From the bottom to the depth of the recess 10 to 60%
While being filled to the height of, and bonded to both sides of this glass ceramic green sheet laminate through an adhesive layer containing glass that acts as a binder during firing,
In addition, since the constraining green sheets that do not shrink substantially during firing are stacked and fired, it is possible to reliably suppress the deformation of the concave portions of the glass-ceramic green sheet laminate and the shrinkage in the laminating plane, and the adhesive layer restrains. Since it is removed together with the sheet, there is an effect that a glass-ceramic substrate having high dimensional accuracy can be obtained, which is free from warpage and deformation, and does not cause deformation in recesses such as cavities.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an example of a laminate in a method for manufacturing a glass ceramic substrate of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Glass-ceramic substrate 1 '... Glass-ceramic / green sheet laminate 2 ... Restraint inorganic substance 2' ... Restraint inorganic composition 3 ... Restraint sheet 3 '... Restraint green sheet A ... Recess

Claims (5)

[Claims] 1. A glass ceramic green sheet laminate having a recess formed by laminating a plurality of glass ceramic green sheets containing an organic binder and having a conductor pattern formed on the surface and glass ceramic green sheets having through holes. A step of producing a body, and a constraining inorganic composition containing a hardly-sinterable inorganic material is provided in the recess of the glass-ceramic green sheet laminate from the bottom surface to a height of 10 to 60% with respect to the depth of the recess. A step of stacking a constraining green sheet containing a hardly-sinterable inorganic material and an organic binder on both surfaces of the glass ceramic green sheet laminate while interposing an adhesive layer containing glass and a solvent, while filling. The organic component is removed from the laminated body of the constrained green sheet and the glass ceramic / green sheet laminated body, and then baked. And holding the constraining sheet and producing a glass-ceramic substrate in which recesses are filled with a constraining inorganic substance, and a step of removing the constraining sheet and the constraining inorganic substance from the glass-ceramic substrate, the adhesive layer The method for producing a glass-ceramic substrate according to claim 1, wherein the glass content of is the amount that binds the constraining green sheet to the glass ceramic green sheet during firing and is removed from the glass-ceramic substrate together with the constraining sheet after firing. 2. The method for producing a glass ceramic substrate according to claim 1, wherein the softening point of the glass contained in the adhesive layer is not higher than the firing temperature of the glass ceramic green sheet laminate. 3. The method for producing a glass ceramic substrate according to claim 1, wherein the softening point of the glass contained in the adhesive layer is higher than the volatilization temperature of the organic component. 4. The method for producing a glass ceramic substrate according to claim 1, wherein the content of glass in the adhesive layer is 5 to 50% by weight of the components of the adhesive layer. 5. The method for manufacturing a glass ceramic substrate according to claim 1, wherein the thickness of the constrained green sheet is 10% or more with respect to the thickness of the glass ceramic green sheet laminate on one surface.