JP2002164653A - Method for manufacturing glass ceramic substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a glass ceramic substrate which reliably constrains sintering shrinkage of a glass ceramic green sheet, has very high dimensional accuracy, and has a good surface state. SOLUTION: The method comprises (i) a step of producing a laminate by laminating a plurality of glass ceramic green sheets each having a conductive pattern formed on the surface, (ii) a step of laminating constraint green sheets containing a hardly sintering inorganic material and an organic binder on both the surfaces of the laminate with an adhesive layer containing a glass and a solvent interposed, (iii) a step of producing a glass ceramic substrate holding the constraint sheet by burning the laminate after removing organic component from the laminate in a state that a load is applied with a weight, (iv) a step of removing the constraint sheet from the substrate. (v) The amount of the glass content in the adhesive layer is such an amount that the constraint green sheets are connected with the glass ceramic green sheet during baking and that the glass content is removed from the glass ceramic substrate with the constraint sheets after baking.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a multi-layer glass ceramic substrate for mounting a semiconductor LSI, chip components and the like and interconnecting them.

[0002]

2. Description of the Related Art In recent years, miniaturization and weight reduction of semiconductor LSIs, chip parts and the like have been promoted, and miniaturization and weight reduction of a wiring board on which these are mounted is also desired. In response to such demands, multilayer ceramic substrates in which internal electrodes and the like are arranged in the substrate have been regarded as important in today's electronics industry because of the required high-density wiring and the possibility of thinning. I have.

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

On the other hand, with the recent era of advanced information technology, the frequency band used has been shifting to higher and higher frequencies. In a high-frequency wiring board for transmitting such a high-frequency signal, in order to transmit a high-frequency signal at a high speed, the resistance of a conductor forming a wiring layer is required to be small. Required.

However, conventional high melting point metals such as tungsten (W) and molybdenum (Mo) have a large conductor resistance, have a low signal propagation speed, and have difficulty in signal propagation 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 a low resistance metal such as u). However, since the low-resistance metal as described above has a low melting point, 800
Since it is necessary to fire at a low temperature of about 1100 ° C., the wiring layer made of a low-resistance metal cannot be fired at the same time as alumina which needs to be fired at a high temperature. Further, since the alumina substrate has a high dielectric constant, it is not suitable for a high-frequency circuit board.

For this reason, attention has recently been paid to using glass ceramics obtained by firing a mixture of glass and ceramics (inorganic filler) as an insulating substrate. That is, glass ceramics have a low dielectric constant and are therefore suitable as high-frequency insulating substrates, and glass ceramics can be fired at a low temperature of 800 to 1100 ° C., so that a low-resistance metal such as copper, silver, or gold can be used as a wiring layer. There is an advantage that can be used as.

A multilayer glass ceramic substrate is prepared by adding a mixture of glass and a filler to an organic binder, a plasticizer, a solvent and the like to form a slurry, forming a glass ceramic green sheet with a doctor blade or the like, and then forming a copper, silver, gold or the like. A conductive pattern is formed on the green sheet, for example, by printing a conductive paste containing a low-resistance metal powder, and then a plurality of green sheets are laminated to 800 to 110
It is obtained by firing at a temperature of 0 ° C.

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

First, when producing a screen plate for printing internal electrodes, the size of the screen plate must be determined by calculating backward from the contraction ratio of the substrate. Since it is not constant, the screen plate must be remade for each production lot of the substrate, which is uneconomical and impractical. Further, in a multilayer glass ceramic substrate manufactured by the above-described green sheet laminating method, since the shrinkage ratio in the vertical direction and the horizontal direction in the laminating plane differs depending on the film forming direction of the green sheet, the manufacturing of the multilayer glass ceramic substrate is difficult. It becomes even more difficult.

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

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

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

(1) A glass ceramic green sheet containing a glass ceramic component and an organic component such as a binder and a plasticizer, on which a conductor pattern is formed, is laminated in a desired number, and (2) the obtained glass ceramic green sheet. A laminated 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 and a plasticizer is laminated on both surfaces or one surface of the laminate, and (3) these glass ceramic green sheets Heating the laminate of the laminate and the restrained green sea,
First, the organic component is removed, and then firing is performed to form a glass ceramic substrate and a restraining sheet, respectively. (4) Finally, the restraining sheet is removed from the glass ceramic substrate.

According to this method, the restrained green sheet restrains the shrinkage of the glass-ceramic green sheet during firing, so that the shrinkage occurs only in the thickness direction of the laminated body, and in the vertical and horizontal directions of the laminated surface. It is considered that shrinkage does not occur and the dimensional accuracy of the glass ceramic substrate is improved.

[0015]

In the above method, the bonding between the glass ceramic green sheet and the restrained green sheet is performed by an organic component such as a binder contained in the green sheet. But,
In the firing step (3), after the organic components such as the binder and the plasticizer are decomposed and volatilized, the powder in the constrained green sheet and the powder in the glass ceramic green sheet simply come into close contact with each other. There is only a weak bond between the sheets due to van der Waals forces.

Although such a weak bond has the advantage that the removal of the constrained sheet in the step (4) is easy, the constrained green sheet is removed from the glass-ceramic green sheet laminate in the firing step (3). May be inadvertently peeled off due to a difference in thermal expansion between the two.

If the constrained green sheet peels off during firing, sintering shrinkage of the glass ceramic green sheet cannot be prevented. Further, even if the detachment of the constrained green sheet is only a part, the shrinkage occurs in the part, so that the glass ceramic substrate is deformed.

Further, since the glass ceramic green sheet laminate and the constrained green sheet have a small bonding force,
Depending on the state of their adhesion 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, their bonding strength tends to be uneven. If the bonding force is uneven, the force for restraining the sintering shrinkage of the glass ceramic will be uneven, and the shrinkage will occur, and the glass ceramic substrate will be warped or deformed. As a result, there is a problem that a substrate having high dimensional accuracy cannot be obtained.

Further, the glass-ceramic substrate is usually manufactured in a square shape such as a square or a rectangle, and the laminate of the glass-ceramic green sheet laminate and the constrained green sheet having such a shape is fired. In this case, the corners of the sintered glass ceramic substrate may warp upward.

The cause of this is that shrinkage in the lamination plane of the glass ceramic substrate is suppressed by the constraint sheets laminated on both sides of the glass ceramic substrate, but there is no constraint sheet on the side surface of the glass ceramic substrate, and It is considered that the shrinkage stress at the time of sintering tends to concentrate on the corner portions of the above. Also, the difference in the area of the metallized conductor pattern formed on the upper and lower surfaces of the glass ceramic substrate,
It may be warped as a whole due to the temperature difference and calorific value difference between the upper and lower surfaces during firing.

When the corners of the glass ceramic substrate are warped in this manner, when a resistor paste is screen-printed on this substrate to form a resistor pattern, or when a solder paste for component mounting is printed, In addition, there is a problem that these printing becomes difficult. On the other hand, it is conceivable to add a step of removing a warped corner portion of the substrate after firing, but the step becomes complicated and uneconomical. Further, there is a problem that if the overall warpage is large, the entire substrate cannot be used.

An object of the present invention is to reliably restrain sintering shrinkage in the laminating plane of a glass ceramic green sheet,
It is another object of the present invention to provide a method of obtaining a glass ceramic substrate having higher dimensional accuracy by applying a load by weight to the glass ceramic substrate without warping of a corner portion of the glass ceramic substrate.

[0023]

Means for Solving the Problems The inventors of the present invention have made intensive studies to solve the above-mentioned problems, and as a result, (I) a glass component was contained between the constrained green sheet and the glass ceramic green sheet. If an adhesive layer is interposed,
Since the glass component acts as a bonding material for bonding the glass ceramic green sheet and the constrained green sheet during the firing process, the bonding force therebetween is increased, and the constrained green sheet can be prevented from peeling off. (II) The content of the glass component in the adhesive layer is the amount removed from the glass ceramic substrate together with the constrained sheet after firing. As a result, (III) the constrained green sheet ensures that the glass ceramic green sheet laminate shrinks. It is possible to obtain a glass-ceramic substrate with reduced dimensional accuracy, and (IV) warpage at corners by applying a load due to weight to the laminated body of the glass-ceramic green sheet laminate and the restrained green sheet. Glass ceramic substrate with higher dimensional accuracy Have found a new fact that it is possible to obtain the present invention, and have completed the present invention.

That is, the method for manufacturing a glass ceramic substrate according to the present invention comprises the steps of: (i) laminating a plurality of glass ceramic green sheets each containing an organic binder and having a conductive pattern formed on the surface thereof. (Ii) a constrained green containing a non-sinterable inorganic material and an organic binder with an adhesive layer containing glass and a solvent interposed on both sides of the glass-ceramic green sheet laminate; And (iii) removing an organic component from the laminate while applying a load by weight to the laminate of the constrained green sheet and the glass ceramic green sheet laminate, and then firing. Preparing a glass ceramic substrate holding the restraining sheet, and (iv) removing the restraining sheet from the glass ceramic substrate. (V) the glass content of the adhesive layer is such that the constrained green sheet is bonded to the glass ceramic green sheet during firing and removed from the glass ceramic substrate together with the constrained sheet after firing. There is a feature.

In the present invention, the softening point of the glass contained in the adhesive layer is preferably not higher than the firing temperature of the glass-ceramic green sheet laminate. Thereby, the glass in the restrained green sheet 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. If the softening point of the glass is lower than the volatilization temperature of the organic component, there is a possibility that the removal path for passing the decomposed and volatilized organic component will 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 constrained green sheet during lamination, is combined with the glass ceramic green sheet during firing, and is removed from the glass ceramic substrate together with the constrained sheet after firing. Become. If the amount is less than 5% by weight, the amount of glass that acts as a binder during firing is small, so that the binding between the restraining 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 in which the constrained green sheet and the glass ceramic green sheet are in close contact with each other during lamination is small, and there is a possibility that the adhesiveness before firing may deteriorate. In addition, 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. The glass content varies depending on the type of glass used and the like, but is preferably about 5 to 50% by weight.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The method for manufacturing a glass ceramic substrate according to the present invention will be described in detail below.

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

As the glass component, for example, SiO_Two-B_Two
O_ThreeSystem, SiO_Two-B_TwoO_Three-Al_TwoO_ThreeSystem, SiO_Two-B_TwoO
_Three-Al_TwoO_Three-MO system (where M is Ca, Sr, Mg,
Ba or Zn), SiO_Two-Al_TwoO_Three-M¹O-
M^TwoO type (however, M¹And M ^TwoAre the same or different C
a, Sr, Mg, Ba or Zn), SiO_Two−
B_TwoO_Three-Al_TwoO_Three-M¹OM^TwoO type (however, M¹and
M^TwoIs the same as described above), SiO 2_Two-B_TwoO_Three-M^Three _TwoO system
(However, M^ThreeRepresents Li, Na or K), SiO_Two−
B_TwoO_Three-Al_TwoO_Three-M^Three _TwoO type (however, M^ThreeIs the same as above
), Pb-based glass, Bi-based glass and the like.
You.

As the filler, for example, Al
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, at least one selected from Al ₂ O ₃ and SiO ₂ And the like (for example, spinel, mullite, cordierite).

The mixing ratio of the above glass and filler is a ratio used for ordinary glass ceramic substrate materials, and is preferably 40:60 to 99: 1 by weight.

As the organic binder compounded in the glass ceramic green sheet, those conventionally used for ceramic green sheets can be used.
For example, acrylic (a homopolymer or a copolymer of acrylic acid, methacrylic acid or an ester thereof, specifically, an acrylate ester copolymer, a methacrylate ester copolymer, an acrylate-methacrylate ester copolymer) And the like, and homo- or copolymers such as polyvinyl butyral, polyvinyl alcohol, acryl-styrene, polypropylene carbonate, and cellulose.

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 glass powder, filler powder and organic binder, if necessary, to obtain a slurry. Approximately 50-500μm thick by rolling, calender roll, die press, etc.
It is obtained by molding.

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

The conductor pattern on the surface 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, for example, embedding a conductor material powder paste (conductor paste) into a through hole formed in a glass ceramic green sheet by punching or the like by printing.

For the lamination of the glass ceramic green sheets, a method of applying heat and pressure to the stacked green sheets for thermocompression bonding, or applying an adhesive comprising an organic binder, a plasticizer, a solvent, or the like between the sheets to perform thermocompression bonding And the like.

The constrained green sheet of the present invention is obtained by molding a slurry in which an organic binder, a plasticizer, a solvent, and the like are added to an inorganic component made of a non-sinterable inorganic material. Examples of the non-sinterable inorganic material include at least one selected from Al ₂ O ₃ and SiO _2, but are not limited thereto.

Further, the same glass component as that of the adhesive layer may be contained in the constrained green sheet to further increase the bonding force between the constrained green sheet and the glass ceramic green sheet. In this case, the amount of the glass component is preferably an amount that does not substantially shrink the constrained green sheet in the lamination plane during firing.

The thickness of the constrained green sheets laminated on both sides of the glass ceramic green sheet is preferably at least 10% of the thickness of the glass ceramic green sheet laminate on only one side, and more preferably less than 10%. If it is thin, the restraint of the restrained green sheet may be reduced. In addition, considering the ease of volatilization of the organic component and the removal of the constrained sheet from the glass ceramic substrate, the thickness of the constrained green sheet is preferably not more than about 200% of the thickness of the glass ceramic green sheet laminate. . Further, a single restraining sheet may be stacked, or a plurality of restraining sheets may be stacked so as to have a predetermined thickness.

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, plasticizer and solvent, the same materials as those used for the glass ceramic green sheet can be used. Here, the reason for adding the plasticizer is to impart flexibility to the constrained green sheet and increase the adhesion to the glass ceramic green sheet during lamination.

The adhesive for forming the adhesive layer is glass powder,
A mixture of an organic solvent and the like is used. Further, by incorporating an organic binder component, the bonding strength between the green sheets before firing can be increased, or the viscosity can be adjusted to facilitate application. Further, a dispersant or the like can be added to improve the dispersibility of the glass in the adhesive.

The glass in the adhesive is not particularly limited, and the same glass as that used for the glass ceramic green sheet can be used. The glass in the adhesive is glass ceramic
The glass 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 not higher than the firing temperature of the glass ceramic green sheet laminate and higher than the decomposition / volatilization temperature of the organic components in the green sheet. Specifically, the softening point of the glass in the adhesive is preferably about 450 to 1100 ° C. If the softening point of the glass is lower than 450 ° C, when removing organic components from the glass ceramic green sheet, the softened glass will block the removal path of the organic components decomposed and volatilized, and the organic components will be completely removed It may not be possible. On the other hand, when the softening point of the glass exceeds 1100 ° C., it may not work as a binder to the green sheet under ordinary firing conditions of the glass ceramic green sheet.

The particle size of the glass in the adhesive is desirably 10 μm or less. If it is larger than this, glass particles may bite into the conductor pattern on the glass ceramic green sheet when laminating the green sheet, thereby increasing the surface roughness of the conductor after firing or causing defects in the conductor. This is because there is a risk of doing so. Note that such a restriction is not applied when the constrained green sheet is softer than the conductor pattern and the glass bites into the constrained green sheet.

The solvent in the adhesive is not particularly limited as long as it disperses the glass uniformly and does not inhibit the bonding between the green sheets. Further, a plurality of solvents can be used as a mixture. It is preferable to use a material that imparts flexibility to the green sheet, swells or dissolves the surface of the green sheet to increase the bonding force between the green sheets, and 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 a different solvent may be used depending on the green sheet.

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

After producing a laminate formed by laminating the constrained green sheets, the organic components are removed and baked. The organic component is removed by heating the laminate at a temperature in the range of 100 to 800 ° C. to decompose and volatilize the organic component.
The firing temperature varies depending on the glass ceramic composition, but is usually in the range of about 800 to 1100 ° C. Usually, firing is performed in the air. However, when Cu is used as the conductor material, the 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.

At the time of removing and firing the organic components, a load is applied by placing a weight on the upper surface of the laminate in order to prevent the glass ceramic substrate from warping.

It is appropriate that the load due to the weight is about 50 Pa to 1 MPa. If the load is less than 50 Pa, the function of suppressing the warpage at the corners of the laminate may not be sufficient. On the other hand, if the load exceeds 1 MPa, the weight to be used will be large, and the weight will not enter the firing furnace, and even if it enters the firing furnace, the heat capacity will be insufficient due to the large weight. This may cause problems such as inability to fire properly.

The size of the weight is preferably such that a desired load is applied to each corner of the glass ceramic green sheet laminate, and is substantially the same as that of the glass ceramic green sheet laminate. A plate having a size equal to or larger than that is preferable, but a plurality of weights may be used so that a load can be applied to each corner.

The weight is made of a heat-resistant material which does not deform or melt during firing of the glass ceramic substrate to make the load nonuniform or to prevent the volatilization of the decomposed organic components. Is suitable. Specific examples include refractories such as ceramics, and metals having a high melting point. Further, for such a weight, it is preferable to use a porous body in which at least a portion in contact with the upper surface of the laminate is porous. This means that if a weight of the dense body is used, a removal path for passing the organic components decomposed and volatilized from the laminate may not be sufficiently secured on the upper surface of the laminate abutted by the weight, Organic components, especially carbon components, remain in the glass ceramic substrate, and the color tone of the substrate becomes dark,
This is because the properties of the glass ceramic are degraded, and in severe cases, sintering is hindered and the glass ceramic substrate may not be dense. In order to ensure a sufficient path for removing organic components volatilized from the laminate while applying a uniform load as a weight, for example, sintering of a porous material such as a pumice-like material having a large number of air bubbles or a fibrous alumina-like material It is preferable to use a material having a structure in which pores are uniformly distributed, such as a gas-permeable porous body, or a honeycomb structure or a mesh having a large porosity of about 30% or more.

Further, a porous first weight is placed on the upper surface of the laminate so as not to hinder the volatilization of the decomposed organic component, and a non-porous second weight is placed thereon so as to apply a sufficient load. You may put weight.

In order to effectively suppress the warpage at the corners of the glass-ceramic substrate by applying a uniform load to the laminate, basically, the surface where the weight contacts the laminate should be flat. Although it is necessary, when a honeycomb plate or the like is used as a porous body as a weight, and the perforated surface is in contact with the porous body, it is necessary that the surface excluding the hole portion has a smaller curvature than a predetermined curvature. It is.

After firing, the restraining sheet is removed. here,
The adhesive layer can be removed together with the restraining sheet. The removal method is not particularly limited as long as it can remove the constraining sheet and the adhesive layer bonded to the surface of the glass ceramic substrate. For example, ultrasonic cleaning, polishing, water jet, chemical blast, sand blast, wet blast (polishing) A method of injecting particles and water by air pressure).

In the obtained multilayer glass ceramic substrate, shrinkage during firing is suppressed only in the thickness direction by the constrained green sheet, so that shrinkage in the lamination plane is reduced to about 0.1 mm.
It can be reduced to 5% or less, and the glass ceramic green sheet is evenly and securely bonded by the constrained green sheet under the load by weight, so a part of the constrained green sheet It is possible to prevent warpage or deformation due to peeling or the like, and effectively prevent warpage from occurring at a corner portion of the substrate.

FIG. 1 is a sectional view showing an example of the embodiment of the method for manufacturing a glass ceramic substrate according to the present invention as described above. In FIG. 1, 1 is a glass ceramic green sheet laminate, 2 is a constrained green sheet laminated on the upper and lower surfaces thereof via adhesive layers (not shown), 3 is a constrained green sheet 2 and a glass ceramic green sheet laminate 1 And a weight placed on the upper surface of the laminate. Also, 4
Is a setter for placing these and putting them into the firing furnace.

After the organic component is removed from the laminate of the constrained green sheet 2 and the glass ceramic green sheet laminate 1 under a predetermined load applied by the weight 3, the glass ceramic green sheet is fired. By removing the constrained sheet obtained from the constrained green sheet 2 from the glass ceramic substrate obtained by sintering the sheet laminate 1, there is no occurrence of warpage in the corner portion.
A glass ceramic substrate with extremely high dimensional accuracy can be obtained.

[0059]

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

(Example 1) As glass ceramic components, SiO ₂ -Al ₂ O ₃ -MgO-B ₂ O ₃ -ZnO based 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 mixed by a ball mill method to form a slurry. Using this slurry, a glass ceramic green sheet having a thickness of 300 μm was formed by a doctor blade method.

Then, a conductor pattern was formed on the 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 100 parts by weight of an alloy powder (average particle size: 1.0 μm) having a weight ratio of 85:15 of Ag: Pd and glass powder 2 having the same composition as the above glass were used. Parts by weight and a predetermined amount of an ethylcellulose-based resin and terpineol as a vehicle component were further added and mixed with a three-roll mill so as to obtain an appropriate viscosity.

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

The adhesive was 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 each having a conductor pattern formed on the surface are stacked to obtain a glass ceramic green sheet laminate, and further, on both sides thereof, constrained green sheets coated with an adhesive are laminated.
The laminate was obtained by pressure bonding at a temperature of 55 ° C. and a pressure of 20 MPa.

The obtained laminate was placed on an alumina setter, and a porous ceramic plate having a porosity of 75% was placed on the laminate as a weight, so that the laminate was averagely placed on the laminate.
After applying a load of 100 Pa and heating at 500 ° C. in the air for 2 hours to remove organic components, firing was performed at 900 ° C. for 1 hour. After the firing, the constraint sheets were adhered to both surfaces of the glass ceramic substrate. In this state, the restraining sheet was not peeled off even if it was hit lightly.

Most of the constraining sheet adhered to the surface of the glass ceramic substrate could be removed by scraping, but it remained thinly on the surface of the glass ceramic substrate. The remaining constrained sheet was removed by a wet blast method in which a mixture of spherical Al ₂ O ₃ fine powder and water was projected with high air pressure. The surface of the glass ceramic substrate after removing the restraining sheet has a surface roughness (arithmetic average roughness) Ra of 1
It became a smooth surface of μm or less, and there was no problem with the solder wettability of the conductor.

The shrinkage of the obtained glass ceramic substrate in the lamination plane was 0.5% or less, and no warping or deformation was observed in the substrate.

(Examples 2 and 3) The softening point was 600
A glass-ceramic substrate was obtained in the same manner as in Example 1 except that the adhesive was prepared using glass at 700 ° 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 produced using glass having a softening point of 400 ° C.

As a result, the glass-ceramic substrates obtained in Examples 2 and 3 exhibited a shrinkage of 0.5% or less (that is, a shrinkage of 99.5% or more) in the lamination plane, as in Example 1. No warping 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. Therefore, the restrained green sheet was easily peeled off from the fired glass ceramic substrate. In addition, since the bonding force between the glass ceramic green sheet and the restraint green sheet is weak,
The shrinkage ratio of the glass-ceramic substrate in the lamination plane was about 85%, or the glass-ceramic substrate was greatly deformed because only a part of the substrate was bonded to the restraining 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 components were not completely removed, so that the shrinkage in the lamination plane of the glass ceramic substrate was 0.5% or less. Although good, the color tone of the glass ceramic substrate became gray.

(Examples 4 to 7) As a glass ceramic component, 70% by weight of SiO ₂ —MgO—CaO—Al ₂ O ₃ -based glass powder and 30% by weight 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 mixed by a ball mill method to form a slurry. Using this slurry, a glass ceramic green sheet having a thickness of 300 μm was formed by a doctor blade method.

Then, Example 1 was placed on this green sheet.
A conductor pattern was formed by screen printing using the same silver-palladium paste as described above.

The same restricted green sheet as in Example 1 was prepared.

On the other hand, the adhesive was SiO ₂ -M having a softening point of 720 ° C.
gO-CaO-Al ₂ O ₃ based glass powder and DBP, BC
A and A were prepared by mixing acrylic binders in proportions shown in Table 1.

A predetermined number of glass-ceramic green sheets having a conductive pattern formed on the surface are stacked to obtain a glass-ceramic green sheet laminate, which is further applied to both surfaces by screen printing on the surface to be attached to the laminate. The constrained green sheets on which the adhesive layer was formed were overlaid and pressed at a temperature of 55 ° C. and a pressure of 20 MPa to obtain a laminate.
This laminate was a rectangle having a size of 150 mm × 120 mm.

The obtained laminate is placed on an alumina setter, and a porous ceramic plate having a porosity of 50% is placed on the laminate so that an average load of 50 Pa is applied to the laminate. After heating at 500 ° C. in the air for 2 hours to remove organic components, firing was performed at 850 ° C. for 1 hour. Next, the constraint sheet adhered to the surface of the glass ceramic substrate was removed. The surface of the obtained glass ceramic substrate is
The surface became smooth with a surface roughness Ra of 1 μm or less, and there was no problem with the solder wettability of the conductor.

Table 1 also shows the shrinkage ratio of the obtained glass ceramic substrate in the lamination plane. No warpage or deformation was observed in the glass ceramic substrate.

[0082]

[Table 1]

From Table 1, it can be seen that the glass-ceramic substrates obtained by using each of the adhesives of Examples 4 to 7 are suppressed in shrinkage during firing and have high dimensional accuracy. In the results shown in Table 1, the warpage is measured by using a laser optical non-contact three-dimensional shape measuring apparatus to measure the warpage height.

[0084]

According to the present invention, the glass ceramic green sheet laminate is bonded to both sides of the glass ceramic green sheet laminate via an adhesive layer containing glass which acts as a binder during firing.
In addition, since the restrained green sheets that do not substantially shrink during firing are stacked and fired, shrinkage in the stacking surface of the glass ceramic green sheet substrate can be reliably suppressed,
In addition, since a weight is applied and a load is applied during the removal and firing of the organic components from the laminate, the corner portion can be prevented from warping, and the adhesive layer is removed together with the restraining sheet. Therefore, there is an effect that a glass ceramic substrate having higher dimensional accuracy without warpage or deformation can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of an embodiment of a method for manufacturing a glass ceramic substrate according to the present invention.

[Explanation of symbols]

 1 ・ ・ ・ Glass ceramic green sheet laminate 2 ・ ・ ・ Restricted sheet 3 ・ ・ ・ Weight

Claims (7)

[Claims] A step of forming a glass ceramic green sheet laminate by laminating a plurality of glass ceramic green sheets each containing an organic binder and having a conductor pattern formed on a surface thereof; A step of laminating a constrained green sheet containing a non-sinterable inorganic material and an organic binder with an adhesive layer containing glass and a solvent interposed on both surfaces of the body, and the constrained green sheet and the glass ceramic green sheet A step of producing a glass-ceramic substrate holding a constrained sheet by removing organic components from the laminate while applying a load by weight to the laminate with the laminate, and then firing the glass-ceramic substrate; Removing the binding sheet, wherein the glass content of the adhesive layer is such that the binding green A method of manufacturing a glass ceramic substrate, wherein the amount of the sheet is combined with the glass ceramic green sheet and removed from the glass ceramic substrate together with the constraint 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 according to claim 1, wherein the glass contained in the adhesive layer has a softening point higher than a volatilization temperature of the organic component. 4. The method according to claim 1, wherein the glass content in the adhesive layer is 5 to 50% by weight of the components of the adhesive layer. 5. The method according to claim 1, wherein the thickness of the constrained green sheet is 10% or more of the thickness of the glass ceramic green sheet laminate on one side. 6. The load caused by the weight is 50 Pa to 1 MPa.
The method for manufacturing a glass ceramic substrate according to claim 1, wherein 7. The method according to claim 1, wherein the weight is a porous body.