JP2003069223A - Method for manufacturing glass ceramic substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for obtaining a glass ceramic substrate in which a sintering shrinkage of a glass ceramic green sheet is surely restricted, which has a high dimensional accuracy and high reliability without deteriorating an insulation of a glass ceramic coating layer. SOLUTION: The method for manufacturing the glass ceramic substrate comprises (1) a step of manufacturing a laminate 1 by laminating a plurality of glass ceramic green sheets each formed with a conductor pattern, and forming a glass ceramic coating layer 3 so that a thickness after sintering becomes 0.015 to 0.1 mm on a surface of the conductor pattern 2 of the surface, (2) a step of laminating the restricted green sheet containing a hardly sintering inorganic material on both surfaces of the laminate, (3) a step of removing the organic component from the laminate, sintering and manufacturing the glass ceramic substrate in which the restricted sheet is held, and (4) a step of removing the restricted sheet from the substrate in such a manner that (5) a glass content of the restricted green sheet is an amount for not substantially shrinking in a laminate surface by coupling to the glass ceramic green sheet at a baking time.

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 components, etc. 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 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 era of advanced information technology, the frequency band used is increasingly shifting to the high frequency band. 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 and molybdenum have large conductor resistance, slow signal propagation speed, and are difficult to propagate signals in a high frequency region of 30 GHz or more. Instead, it is necessary to use a low resistance metal such as copper, silver or gold. However, since the low-resistance metal as described above has a low melting point, it is necessary to bake at a low temperature of about 800 to 1000 ° C., so that the wiring layer made of the low-resistance metal is alumina that requires high temperature firing. It could not be fired at the same time. Further, since the alumina substrate has a high dielectric constant, it is not 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 1000 ° 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, etc. to a mixture of glass and a filler, and after forming a glass ceramic green sheet with a doctor blade or the like, copper, silver, gold, etc. Forming a conductor pattern on the green sheet by printing a conductor paste containing a low-resistance metal powder, and then laminating a plurality of green sheets to form 800 to 100
It is obtained by firing at a temperature of 0 ° 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 an error in shrinkage of about ± 0.5% will inevitably occur.

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 each containing a glass ceramic component and an organic component such as a binder and a plasticizer and having conductor patterns formed thereon are laminated, (2)
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 obtained glass ceramic green sheet laminate, 3) Heating the laminated body of the glass ceramic green sheet and the constrained green sheet to remove organic components first, and then firing to form a glass ceramic substrate and a constrained sheet, respectively (4) Last First, 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, the 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.

[0014]

In the above method, the glass-ceramic green sheet and the constraining green sheet are bonded to each other 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 are simply brought into close contact with each other. There is only a weak bond between the sheets due to van der Waals forces.

Such a weak bond may cause the constrained green sheet to be inadvertently peeled off from the glass ceramic / green sheet laminate in the firing step (3) due to a difference in thermal expansion between them.

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 ceramics is also uneven, resulting in uneven shrinkage and warping or deformation of the glass ceramic substrate. As a result, there is a problem that a substrate with high dimensional accuracy cannot be obtained.

Further, on the surface of the glass ceramic substrate, a glass ceramic coating layer is usually formed on the surface of the conductor pattern in order to form a pattern for mounting a semiconductor element or the like, but it is often manufactured. Such a glass ceramic coating layer may cause minute cracks or peel off when the constraining sheet is removed.

The cause of this is that the conventional glass ceramic coating layer has a thickness of about 0.01 mm after firing, and at this thickness, abrasive particles such as sand blast and wet blast when removing the constraining sheet cause glass ceramic coating layer. It is considered that the impact force is transmitted to the interface between the glass-ceramic coating layer and the metallization or the glass-ceramic substrate by the collision with the and the peeling easily occurs.

When the glass ceramic coating layer is cracked or peeled off, a resistor paste is screen-printed on the substrate to form a resistor pattern, or a solder paste for mounting components is printed. However, there is a problem in that printing of these becomes difficult. Further, there is a problem that a crack progresses due to heat stress due to heat generation when a semiconductor element or the like is mounted and operated, and the insulation property is deteriorated to lower reliability.

An object of the present invention is to reliably restrain the sintering shrinkage within the laminated surface of the glass ceramic green sheet,
Another object of the present invention is to provide a method for obtaining a highly reliable glass ceramic substrate with high dimensional accuracy by suppressing the peeling and cracking of the glass ceramic coating layer.

[0022]

Means for Solving the Problems As a result of intensive studies conducted by the present inventors to solve the above problems, (I) if a glass component is contained in the constrained green sheet, the glass component will burn. In the process, it acts as a binding material that joins the glass ceramic green sheet and the constraining green sheet, so that the binding force between them can be increased and the constraining green sheet can be prevented from peeling off. (II) Restraining green during firing Sintering shrinkage of the sheet itself can be substantially avoided by setting the glass content within a predetermined range, and as a result, the shrinkage of the glass ceramic / green sheet laminate is surely suppressed by (III) the restraining green sheet. It is possible to obtain a glass ceramic substrate with high dimensional accuracy, and (IV) the thickness of the glass ceramic coating layer after firing is 0.0 By setting the thickness to 15 to 0.1 mm, it is possible to suppress the peeling and cracking of the glass ceramic coating layer, find a new fact that it is possible to obtain a glass ceramic substrate with high dimensional accuracy and high reliability, The present invention has been completed.

That is, in the method for producing a glass ceramic substrate of the present invention, (i) a plurality of glass ceramic green sheets containing an organic binder and having a conductor pattern formed on the surface thereof are laminated to laminate the glass ceramic green sheets. While making the body,
A step of forming a glass ceramic coating layer on the surface of the conductor pattern on the surface of the green sheet laminate so that the thickness after firing becomes 0.015 to 0.1 mm; and (ii) on both surfaces of the glass ceramic green sheet laminate. A step of laminating a constrained green sheet containing a hardly-sinterable inorganic material, glass and an organic binder, and (iii) removing an organic component from the laminated body of the constrained green sheet and the glass ceramic green sheet laminate, Then, firing, to produce a glass-ceramic substrate holding the restraint sheet,
(Iv) removing the constraining sheet from the glass ceramic substrate, and (v) the glass content of the constraining green sheet is such that the constraining green sheet is combined with the glass ceramic green sheet during the firing and the constraining green sheet. The sheet is characterized in that the amount is such that the sheet does not substantially shrink in the laminating plane.

Here, "not substantially shrink" means
Shrinkage of constrained green sheets is less than 1%, preferably 0.8
% Or less, more preferably 0.5% or less. The "in-plane" means a plane defined by the X direction and the Y direction when the thickness direction is the Z direction in the three-dimensional coordinate, and specifically, the longitudinal direction and the lateral direction of the sheet. Means

In the present invention, the softening point of the glass contained in the constrained green sheet is preferably not higher than the firing temperature of the glass ceramic green sheet laminate. As a result, the glass in the constrained green sheet is softened in the firing step, and the bonding strength is increased.

The softening point of the glass contained in the constrained green sheet is preferably higher than the removal temperature of the organic component. When the softening point of the glass is lower than the removal 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 constrained green sheet is preferably 0.5 to 15% by weight based on the total inorganic components in the constrained green sheet. Usually, this range is an amount that binds to the glass-ceramic green sheet during firing and does not substantially shrink the constraining green sheet within its laminating plane, but it is not necessarily limited to this range and is used. The glass content changes depending on the type of glass.

[0028]

BEST MODE FOR CARRYING OUT THE INVENTION The glass-ceramic green sheet of 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

As the filler, 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 glass and the filler is preferably 40:60 to 99: 1 by weight.

As the organic binder to be mixed in the glass ceramic green sheet, those conventionally used in 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 prepared 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 brace, etc., thickness about 50-500μ
It is obtained by molding into m.

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 is transferred. And the like. As the conductor material, for example, one kind or two kinds or more of Au, Ag, Cu, Pd, Pt and the like can be mentioned. In the case of two kinds or more, a mixture, an alloy,
It may be in any form such as coating.

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 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.

Next, in order to form a pattern for mounting a semiconductor element or the like on the surface of the obtained glass-ceramic / green sheet laminate, a part of it is exposed on the surface of the conductor pattern on the surface of the laminate. A glass-ceramic coating layer having a substantially square opening of about 2 to 5 mm □ is formed.

It is preferable that the glass ceramic coating layer has a thickness of 0.015 to 0.1 mm after firing in order to suppress the generation of cracks when removing the constraining sheet. When the thickness after firing is less than 0.015 mm, the impact force of the abrasive particles propagates to the interface when the constraining sheet is removed by water jet, sand blast, wet blast, etc., and the glass ceramic coating layer and the metallized conductor pattern or glass ceramic Peeling from the interface with the substrate and partial cracking tend to occur. On the other hand, if the thickness after firing exceeds 0.1 mm, when printing by screen printing or gravure printing, voids are incorporated in the glass ceramic coating layer when the coating paste is dried, and water jet, sand blast, wet blast, etc. Therefore, when the restraint sheet is removed, a partial crack tends to occur due to the impact force.

It should be noted that the glass ceramic coating layer should have a substantially square shape with its corners having a non-rectangular shape as the shape of the opening so that the restraint sheet laminated to cover the glass ceramic coating layer is removed. At this time, it is preferable in that the occurrence of partial cracks in the glass ceramic coating layer starting from the opening is suppressed.

Further, it is preferable that the corners of the substantially quadrangular opening have an arc shape with a radius of 0.02 to 1 mm in order to suppress the occurrence of partial cracks in the glass ceramic coating layer when the constraining sheet is removed. If the radius of the arc-shaped corner portion is less than 0.02 mm, the pressure when removing the restraint sheet tends to concentrate on the corner portion, and partial cracks or peeling generated from the corner portion tends to occur. On the other hand, the radius of the arc-shaped corner is 1 m
When it exceeds m, the shape of the opening, which is usually formed in a size of about 2 to 5 mm □, becomes close to a circular shape, and it tends to be difficult to mount and mount a quadrangular semiconductor element.

To form the glass ceramic coating layer on the surface of the glass ceramic green sheet, the surface of the glass ceramic green sheet on which the conductor pattern is formed is
For example, there is a method of printing a raw material powder such as glass powder, alumina powder and the like, which is mixed with an appropriate organic binder, a plasticizer and a solvent to form a paste (coating paste) by a screen printing method or a gravure printing method. Can be mentioned.

The constrained 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 composed of a hardly sinterable inorganic material and glass. Al ₂ O ₃ and S are used as the non-sinterable inorganic material.
At least one selected from iO ₂ may be mentioned, but the invention is not limited thereto.

The glass added to the constrained green sheet is not particularly limited, and the same glass as the glass compounded in the glass ceramic green sheet described above can be used. Further, the glass in the constrained green sheet may have the same composition as the glass in the glass ceramic green sheet or may have a different composition.

The softening point of the glass in the constrained green sheet 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 constrained green sheet. Specifically, the softening point of the glass in the constrained green sheet is preferably about 450 to 1100 ° C. If the softening point of the glass is less than 450 ° C, the removal of the organic components from the glass-ceramic green sheet will block the removal route of the organic components decomposed and volatilized, and the organic components will be completely removed. It may not be possible. On the other hand, the softening point of glass is 1100 ℃
If it exceeds, there is a possibility that it will not act as a binder to the ordinary glass-ceramic green sheet under the firing conditions.

The constrained green sheet can be obtained by molding with 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 thickness of the constraining green sheet laminated on both sides of the glass ceramic green sheet is preferably 10% or more with respect to the thickness of the glass ceramic green sheet laminate only on one side, and more than 10%. If it is thin, the restraint of the restraint green sheet may be reduced. Further, in consideration of facilitating the volatilization of organic components and removing the constraining sheet from the glass ceramic substrate, the thickness of the constraining green sheet should be about 200% or less of the thickness of the glass ceramic / green sheet laminate. . 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.

In order to laminate the formed constrained green sheets on both sides of the glass-ceramic green sheet, heat and pressure are applied to the stacked green sheets to perform thermocompression bonding, and bonding using an organic binder, a plasticizer, a solvent, etc. A method of applying the agent between the sheets and thermocompression-bonding can be adopted. When an adhesive layer is interposed between the sheets, the adhesive layer may contain the same glass component as that of the constrained green sheet to enhance the bonding force between the sheets.

After stacking the constrained green sheets, the organic components are removed and baked. The organic components are removed by heating the laminate 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 air, but when Cu is used as the conductor material, the organic components are removed in a nitrogen atmosphere containing steam at 100 to 700 ° C., and then firing is performed in a nitrogen atmosphere.

During firing, a load may be applied by placing a weight on the upper surface of the laminate to prevent warpage. A load of about 50 Pa to 1 MPa is suitable. If the load is less than 50 Pa, the warpage suppressing effect of the laminate may not be sufficient. Further, if the load exceeds 1 MPa, the weight to be used becomes large, so that it may not enter the firing furnace, or even if it enters the firing furnace, the heat capacity may be insufficient and firing may not be possible. As the weight, it is preferable to use, for example, porous ceramics or metal so as not to prevent volatilization of decomposed organic components. A porous weight may be placed on top of the stack and a non-porous weight placed on top of it.

After firing, the restraint sheet is removed. The removing method is not particularly limited as long as it can remove the restraint sheet bonded to the surface of the glass ceramic substrate, and includes, for example, ultrasonic cleaning, polishing, water jet, sand blasting, wet blasting (abrasive particles and water by air pressure). And the like).

In the obtained multi-layer glass ceramic substrate, the shrinkage during firing is suppressed only in the thickness direction by the constraining green sheet, so that the shrinkage in the laminating plane is about 0.
It is possible to suppress it to 5% or less, and since the thickness of the glass ceramic coating layer after firing is 0.015 to 0.10 mm, the impact force by ultrasonic waves or abrasive particles when removing the restraint sheet is glass ceramic coating. The layer can absorb, and it is possible to suppress peeling or cracking of the glass ceramic coating layer.

[0052]

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

FIG. 2 is a sectional view showing an example of a glass ceramic / green sheet laminate obtained by the manufacturing method of the present invention. 1 is a glass ceramic / green sheet laminate and 2 is a glass ceramic / green sheet laminate. 1
The conductor pattern on the surface of the conductor pattern, 3 is a glass ceramic coating layer formed on the surface of the conductor pattern 2, and 3a is an opening thereof. <Example 1> As a glass ceramic component, SiO ₂ -
60 wt% of Al ₂ O ₃ —MgO—B ₂ O ₃ —ZnO based glass powder, 20 wt% of CaZrO ₃ powder, 17 wt% of SrTiO ₃ powder and ₃ wt% 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 2 was formed on this green sheet by screen printing using a silver-palladium paste. As the conductor paste, 100: alloy powder having an Ag: Pd weight ratio of 85:15 (average particle size 1.0 μm)
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 glass, and a predetermined amount of ethyl cellulose resin and terpineol as vehicle components are added to obtain an appropriate viscosity by three rolls. The above mixture was used.

Next, the glass ceramic coating layer 3 is formed on the surface of the conductor pattern 2 so as to have a thickness of 0.030 mm after firing, in consideration of the shrinkage rate due to sintering in the firing process, and the conductor pattern 2 3mm square opening 3 with a corner radius of 0.5mm that exposes part of the
a was provided, and it was formed by screen printing using a glass ceramic paste.

As the glass ceramic paste, SiO ₂ --Al ₂ O ₃ --MgO is used as the glass ceramic component.
-B ₂ O ₃ -ZnO based glass powder 60 wt%, CaZrO ₃
20% by weight of powder, 17% by weight of SrTiO ₃ powder and Al ₂ O
₃ powder 3% by weight was used. This glass ceramic powder 1
12 parts by weight of acrylic resin as an organic binder to 00 parts by weight,
2 parts by weight of a phthalic acid-based plasticizer and terpineol as a solvent were added, and the mixture was mixed by a three-roll mill so as to have an appropriate viscosity.

On the other hand, 95% by weight of Al ₂ O ₃ powder as an inorganic component and SiO ₂ —Al ₂ O ₃ —MgO—B ₂ O ₃ having a softening point of 720 ° C.
A ZnO-based glass powder (5% by weight) was used 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.

A glass ceramic green sheet laminate 1 is obtained by stacking a predetermined number of glass ceramic green sheets for the surface layer having the conductor pattern 2 and the glass ceramic coating layer 3 on the surface and glass ceramic green sheets for the inner layer. Further, the constrained green sheets were superposed on both sides thereof, and pressure-bonded at a temperature of 55 ° C. and a pressure of 20 MPa to obtain a laminate.

The obtained laminated body was placed on an alumina setter, and a porous ceramic plate having a porosity of 75% was placed as a weight on the laminated body, whereby the laminated body was evenly averaged.
After applying a load of 100 Pa and heating in air at 500 ° C. for 2 hours to remove organic components, firing was performed at 900 ° C. for 1 hour. After firing, the constraining sheets were attached to both sides of the glass ceramic substrate. In this state, the binding sheet was not peeled off even if tapped lightly.

The restraint sheet adhering to the surface of the glass ceramic substrate was removed by a wet blast method in which a mixture of spherical Al ₂ O ₃ fine powder and water was projected by high-pressure air pressure. The surface of the glass ceramic substrate after removing the restraint sheet becomes a smooth surface having a surface roughness Ra of 1 μm or less,
There was no problem with the solder wettability of the conductor. Moreover, neither peeling nor cracking occurred in the glass ceramic coating layer 3.

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> A glass ceramic substrate was obtained in the same manner as in Example 1 except that constrained green sheets were produced using glasses having softening points of 600 ° C and 700 ° C, respectively.

When the constraining sheet was removed, neither peeling nor cracking occurred in the glass ceramic coating layer 3. <Comparative Example 1> A glass ceramic substrate was obtained in the same manner as in Example 1 except that a constrained green sheet containing no glass was produced. <Comparative Example 2> A glass ceramic substrate was obtained in the same manner as in Example 1 except that a constrained green sheet was produced 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 a constrained green sheet was produced 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 substrate. Moreover, neither peeling nor cracking occurred in the glass ceramic coating layer 3.

On the other hand, in the glass ceramic substrates obtained in Comparative Examples 1 and 2, the constrained green sheets used did not contain glass or contained glass having a softening point higher than the firing temperature. In each case, the restraint green sheet was easily peeled off from the glass ceramic substrate after firing. In addition, since the bonding strength between the glass ceramic green sheet and the constraining green sheet is weak, the shrinkage rate in the laminated surface of the glass ceramic substrate is 85%.
To some extent, the glass-ceramic substrate was significantly deformed because only part of the substrate was bonded to the constraining sheet.

On the other hand, in Comparative Example 3, since the glass contained in the constrained green sheet has a low softening point, the organic component is not completely removed, and therefore the shrinkage in the laminated surface of the glass ceramic substrate is 0.5% or less. Although it was good, the color tone of the glass ceramic substrate became gray. <Examples 4 to 7> SiO was used as a glass ceramic component.
_{2 -MgO-CaO-Al 2 O} 3 based glass powder 70 wt%,
30% by weight of Al ₂ O ₃ powder was used. Acrylic resin as an organic binder is added to 100 parts by weight of this glass-ceramic component.
9.0 parts by weight, 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.
Conductor pattern 2 using the same silver-palladium paste as
Was formed by screen printing.

Next, using the same glass ceramic paste as in Example 1, the glass ceramic coating layer 3 having the same thickness was used.
Was formed by screen printing.

On the other hand, Al ₂ O ₃ powder and SiO ₂ —MgO—CaO—Al ₂ O ₃ glass powder having a softening point of 720 ° C. were used as the inorganic components in the proportions shown in Table 1, respectively, and the above glass ceramic green was used. A slurry was prepared in the same manner as the sheet, and was then molded to obtain a constrained green sheet having a thickness of 250 μm.

A predetermined number of glass ceramic green sheets for the surface layer having the conductor pattern 2 and the glass ceramic coating layer 3 formed on the surface and glass ceramic green sheets for the inner layer are stacked to obtain a glass ceramic green sheet laminate 1. Further, the constrained green sheets were superposed on both sides thereof, and pressure-bonded at a temperature of 55 ° C. and a pressure of 20 MPa to obtain a laminate. This stack has a size of 150 mm x 120
It was a rectangle of mm.

The laminated body thus obtained was placed on an alumina setter, and a porous ceramic plate having a porosity of 50% was placed on the laminated body so that an average load of 50 Pa was applied to the laminated body. After heating in air at 500 ° C. for 2 hours to remove the organic component, it was baked at 850 ° C. for 1 hour. Then, the restraint sheet attached to the surface of the glass ceramic substrate was removed. The surface of the obtained glass ceramic substrate is
The surface roughness Ra was a smooth surface of 1 μm or less, and there was no problem with the solder wettability of the conductor. When the constraining sheet was removed, the glass ceramic coating layer 3 was not peeled off or cracked.

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

[0072]

[Table 1]

From Table 1, it can be seen that the glass-ceramic substrates obtained by using the respective constrained green sheets of Examples 4 to 7 have high dimensional accuracy because shrinkage and warpage during firing are suppressed. . <Comparative Example 4> As a result of being manufactured in the same manner as in Example 1 except that the glass ceramic coating layer 3 had a thickness of 0.01 mm after firing, a water jet, a sandblast,
When the restraint sheet is removed by wet blast or the like, the impact force propagates to the interface and the glass ceramic coating layer 3
Peeling or partial cracking occurred at the interface between the conductor pattern 2 and the glass ceramic substrate. <Comparative Example 5> As a result of being manufactured in the same manner as in Example 1 except that the thickness of the glass-ceramic coating layer 3 after firing was set to 0.20 mm, a glass was obtained when printed by a screen printing method, a gravure printing method, or the like. Voids were incorporated into the glass ceramic coating layer 3 during drying of the ceramic paste, and when the constraining sheet was removed by water jet, sand blasting, wet blasting, etc., a partial crack was generated in the glass ceramic coating layer 3 due to impact force. <Example 8> Cu powder was used instead of AgPd alloy powder in the conductor paste, organic components were removed in a nitrogen atmosphere containing steam at 100 to 700 ° C, and then firing was performed in a nitrogen atmosphere. A glass ceramic substrate was obtained in the same manner as in Example 4. As in Example 4, the shrinkage in the laminated surface was 0.5% or less (that is, the shrinkage ratio was 99.5% or more), and the substrate was not warped or deformed. Further, when the constraining sheet was removed, the glass ceramic coating layer 3 was not peeled or cracked.

<Test Example 1> (Shrinkage test of restraint green sheet) Al as inorganic component
₂O₃Powder and softening point of 720 ℃ SiO₂-MgO-CaO-A
l ₂O₃Using the glass powder and each at a predetermined ratio,
Furthermore, 9.0 parts by weight of acrylic resin as an organic binder,
4.5 parts by weight of phthalic acid plasticizer and toluene 3 as solvent
Add 0 parts by weight and mix them in a ball mill to make a slurry.
- Thick this slurry by doctor blade method
A 250 μm thick restraint green sheet was formed.

This constrained green sheet was placed alone on an alumina setter, heated in the air at 500 ° C. for 2 hours to remove organic components, and then fired at 850 ° C. for 1 hour.

FIG. 1 shows the relationship between the shrinkage factor in the plane of the obtained constraining sheet and the amount of glass added. In addition, the shrinkage ratio shows the average value (n = 5) of the shrinkage ratios in the width direction and the flow direction excluding the thickness direction of the restraint sheet and the variation thereof.
(Dimension after firing) × 100 / (Dimension before firing). Further, the flow direction means the film forming direction of the green sheet, and the width direction means the direction orthogonal to the film forming direction.

As shown in FIG. 1, in order to set the shrinkage ratio to 99.5% or more, that is, to suppress the shrinkage of the constraining sheet to 0.5% or less, the amount of glass added to the constraining green sheet is about 15% by weight or less. It turns out that is desirable. If the amount of glass added exceeds 15% by weight, the shrinkage variation tends to increase. However, when the amount of added glass is small, the constraining property of the glass ceramic green sheet by the constraining green sheet is deteriorated (Comparative Example 1 above).
It is necessary to determine the glass addition amount that does not reduce the restraint property, and in the present invention, 0.5 to 15% by weight is set as a preferable range. <Test Example 2> SiO ₂ -Al ₂ O ₃ -MgO as glass
Except for using the -B ₂ O ₃ -ZnO based glass powder in the same manner as in Test Example 1 was examined the relation between the glass amount and shrinkage, the addition amount of glass is restrained green sheet 15 wt% or less The shrinkage rate was 99.5% or more, and it was maintained at about 99.8% when the amount of glass added was 10% by weight or less.

[0078]

EFFECTS OF THE INVENTION According to the present invention, the constraining green sheets that are combined with the laminated body and do not shrink substantially during firing are laminated and fired on both sides of the glass-ceramic / green sheet laminated body. The shrinkage within the lamination plane of the green sheet substrate can be surely suppressed, and the thickness after firing of the glass ceramic coating layer formed by covering the conductor pattern on the surface of the glass ceramic green sheet laminate is 0.015 to 0.1. Since it is set to mm, peeling and cracking of the glass-ceramic coating layer can be suppressed, warpage and deformation do not occur, the dimensional accuracy is high, and the insulation property of the glass-ceramic coating layer is not deteriorated, which is highly reliable. The effect is that a glass-ceramic substrate having excellent properties can be obtained.

[Brief description of drawings]

FIG. 1 is a graph showing the relationship between the amount of glass added to a constrained green sheet and the shrinkage rate.

FIG. 2 is a cross-sectional view showing an example of a glass ceramic / green sheet laminate obtained by the method for producing a glass ceramic substrate of the present invention.

[Explanation of symbols]

1-Glass ceramic green sheet laminate 2 ... Conductor pattern 3 ... Glass-ceramic coating layer

Claims (5)

[Claims] 1. A glass ceramic green sheet laminate is produced by laminating a plurality of glass ceramic green sheets containing an organic binder and having a conductor pattern formed on the surface thereof, and the glass ceramic green sheet laminate. Forming a glass ceramic coating layer on the surface of the conductor pattern on the surface of the glass ceramic so that the thickness after firing is 0.015 to 0.1 mm; A step of laminating a constraining green sheet containing a water-soluble inorganic material, glass and an organic binder, and removing an organic component from the laminated body of the constraining green sheet and the glass ceramic / green sheet laminate, and then firing the constraining sheet. A step of producing the held glass-ceramic substrate, A step of removing the sheet, wherein the glass content of the constraining green sheet binds the constraining green sheet to the glass ceramic green sheet during the firing and does not substantially shrink the constraining green sheet within its laminating plane. A method for manufacturing a glass-ceramic substrate, characterized in that the amount is a quantity. 2. The method for producing a glass ceramic substrate according to claim 1, wherein the softening point of the glass contained in the constrained green sheet is not higher than the firing temperature of the glass ceramic green sheet laminate. . 3. The method for manufacturing a glass ceramic substrate according to claim 1, wherein the softening point of the glass contained in the constrained green sheet is higher than the volatilization temperature of the organic component. 4. The glass content in the constrained green sheet is 0.5 to 1 of all inorganic components in the constrained green sheet.
The method for producing a glass ceramic substrate according to claim 1, wherein the amount is 5% by weight. 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.