JP2001342076A - Manufacturing method of glass ceramic substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a glass ceramic substrate with very high dimensional accuracy by surely constraining sinter shrinkage of a glass ceramic green sheet. SOLUTION: This manufacturing method is composed of the steps wherein (i) a laminated body is produced by laminating a plurality of glass ceramic green sheets on which surface a conductor pattern is formed; (ii) on both the side of laminated body inorganic paste which contains a hard sintering material, glass, and organic binder is applied and dried, thereby, a constraint inorganic layer is formed; (iii) a glass ceramic substrate with constraint inorganic layer is produced by removing an organic component from laminated body, and burning it; (iv) constraint inorganic layer is removed from above substrate. (v) The amount of the glass contents in constraint inorganic green layer combines with glass ceramic green sheet at the time of burning, causes actually no shrinkage in the laminating layers.

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.

[0004] On the other hand, with the recent era of advanced information technology, the frequency band used is increasingly shifting to a high frequency band. In high-frequency wiring boards that transmit such high-frequency signals, in order to transmit high-frequency signals at high speed, it is required that the resistance of a conductor forming a wiring layer be small, and an insulating substrate also has a lower dielectric constant. Required.

However, conventional high melting point metals such as tungsten and molybdenum have high conductor resistance, slow signal propagation speed, and difficult to propagate signals in a high frequency region of 30 GHz or more. , 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 fire at a low temperature of about 800 to 1000 ° C. Therefore, the wiring layer made of the low-resistance metal is made of alumina that requires high-temperature firing. Co-firing could not be performed. 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.Because glass ceramics can be fired at a low temperature of 800 to 1000 ° C., low-resistance metals such as copper, silver, and gold are used for wiring layers. 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. Form a conductor pattern on the green sheet, such as by printing a conductor paste containing a low-resistance metal powder, and then laminate a plurality of green sheets 800 to 100
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 substrate due to circuit design, manage the substrate 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. 4-293978 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 conductive pattern is formed, is laminated in a desired number, and (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 and a plasticizer is laminated on both surfaces or one surface of the obtained glass ceramic green sheet laminate, 3) The laminate of the glass ceramic green sheet and the constrained green sheet is heated to remove the organic component first, and then fired to form a glass ceramic substrate and a constrained sheet, respectively. Next, the constraint 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.

[0014]

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 an 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 is peeled off during firing, the 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.

Also, since the glass ceramic green sheet laminate and the restrained 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.

An object of the present invention is to reliably restrain sintering shrinkage in the laminating plane of a glass ceramic green sheet,
An object of the present invention is to provide a method for obtaining a glass ceramic substrate having high dimensional accuracy.

[0019]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in order to solve the above-mentioned problems, and as a result, the glass ceramic green sheet laminated body has glass ceramic
An inorganic paste consisting of an inorganic composition that does not sinter at the green sheet sintering temperature, a predetermined amount of glass and an organic binder is applied and dried to form an inorganic constrained green layer, which is then fired and then the constrained inorganic layer is removed By doing so, the present inventors have found a new fact that shrinkage of the glass-ceramic green sheet laminate can be reliably suppressed and a glass-ceramic substrate with high dimensional accuracy can be obtained, 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. And (ii) applying an inorganic paste containing a non-sinterable inorganic material, glass and an organic binder to both sides of the glass-ceramic green sheet laminate and drying to form a constrained inorganic green layer The process of
(Iii) the constrained inorganic green layer and a glass ceramic
Removing the organic component from the laminate with the green sheet laminate, and then baking to produce a glass ceramic substrate holding the constrained inorganic layer; and (iv) removing the constrained inorganic layer from the glass ceramic substrate. (V)
The glass content of the constrained inorganic green layer is an amount that binds the constrained inorganic green layer to the glass ceramic green sheet during the firing and does not substantially shrink the constrained inorganic green layer in the lamination plane thereof. And

Here, "substantially does not shrink" means
Shrinkage of the constrained inorganic green layer is 1% or less, preferably 0.8%
%, More preferably 0.5% or less. In addition, the “in the stacking plane” refers to a plane defined by the X direction and the Y direction when the thickness direction is the Z direction in three-dimensional coordinates, and specifically, the longitudinal direction of the sheet and the It means within a plane defined by a horizontal direction which is a direction orthogonal to the direction.

In the present invention, the softening point of the glass contained in the constrained inorganic green layer is preferably equal to or lower than the firing temperature of the glass ceramic green sheet laminate. Thereby, the glass in the constrained inorganic green layer is softened in the firing step, and the bonding strength is increased.

The softening point of the glass contained in the constrained inorganic green layer is preferably higher than the temperature for removing the organic components. If the softening point of the glass is lower than the temperature at which the organic component is removed, the removal path through which the decomposed and volatilized organic component passes may be blocked by the softened glass.

The glass content in the constrained inorganic green layer is preferably 0.5 to 15% by weight of the total inorganic components in the constrained inorganic green layer. Usually, this range is an amount that binds to the glass ceramic green sheet during firing and does not substantially shrink the constrained inorganic green layer within the lamination plane, but is not necessarily limited to this range, and The glass content varies depending on the type of glass used and the like.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION The glass-ceramic green sheet of the present invention is a mixture of a glass powder, a filler powder (ceramic powder), an organic binder, a plasticizer, and an organic solvent.

As the glass component, for example, SiO 2_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 preferably 40:60 to 99: 1 by weight.

As the organic binder compounded in the glass ceramic green sheet, those conventionally used in 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-mentioned glass powder, filler powder and organic binder, if necessary, to obtain a slurry. , Rolling, calender roll, mold breath, etc., thickness about 50 ~ 500μ
m.

In order to form a conductive pattern on the surface of the glass ceramic green sheet, for example, a paste of a conductive 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. Examples of the conductor material include one or more of Au, Ag, Cu, Pd, and Pt. In the case of two or more, a mixture, an alloy,
Any form such as 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 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 composed of an organic binder, a plasticizer, a solvent, etc. between the sheets to perform thermocompression bonding And the like.

The constrained inorganic green layer in the present invention is obtained by applying an inorganic paste comprising an inorganic component comprising a hardly sinterable inorganic material and glass to which an organic binder, a plasticizer, a solvent, and the like are added, onto a glass ceramic green sheet laminate. Obtained by drying. This coating is performed over the entire surface of both sides of the glass ceramic green sheet laminate by a printing method or the like. As the non-sinterable inorganic material, Al ₂ O ₃ and SiO
_At least one selected from ₂ is mentioned, but is not limited thereto.

The glass added to the constrained inorganic green layer is not particularly limited, and the same glass as that used for the glass ceramic green sheet described above can be used. Further, the glass in the constrained inorganic green layer 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 inorganic green layer 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 constrained inorganic green layer. Specifically, the softening point of the glass in the constrained inorganic green layer 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, the softening point of glass is 1100 ℃
If the ratio exceeds the above, there is a possibility that the glass ceramic green sheet may not function as a binder to the green sheet under ordinary firing conditions.

As the organic binder, plasticizer and solvent, the same materials as used for the glass ceramic green sheet can be used. The plasticizer imparts flexibility to the constrained inorganic green layer, and the glass ceramic and
It may be added to enhance the adhesion to the green sheet.

The thickness of the constrained inorganic green layer laminated on both sides of the glass ceramic green sheet is preferably at least 10% with respect to the thickness of the glass ceramic green sheet laminate on one side only. If the thickness is too small, the restraining property of the restrained inorganic green layer may be reduced. Considering the ease of volatilization of organic components and the removal of the constrained inorganic layer from the glass ceramic substrate after firing, the thickness of the constrained inorganic green layer is about 200% or less of the thickness of the glass ceramic green sheet laminate. It is good. Further, the constrained inorganic green layer to be laminated may be a single layer, or may be a layer in which a plurality of layers are laminated so as to have a predetermined thickness. The specific thickness is 50
It is appropriate that the thickness is about 300 μm.

After laminating the constrained inorganic green layer, organic components are removed and baked. The removal of the organic component is performed 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.

During firing, a load may be applied by placing a weight on the upper surface of the laminate in order to prevent warpage. It is appropriate that the load due to such weight is about 50 Pa to 1 MPa. If the load is less than 50 Pa, the function of suppressing the warpage of the laminate may not be sufficient.
If the load exceeds 1 MPa, the weight to be used will be large, and it will not be able to enter the sintering furnace. It may cause problems such as being unable to do so.

The weight may be 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 the decomposed organic component is suitable. Specific examples include refractories such as ceramics, and metals having a high melting point. Further, a porous weight may be placed on the upper surface of the laminate, and a non-porous weight may be placed thereon.

After firing, the constrained inorganic layer is removed. The removal method is not particularly limited as long as it can remove the constrained inorganic layer bonded to the surface of the glass ceramic substrate. For example, ultrasonic cleaning, polishing, water jet, chemical blast, sand blast, wet blast (abrasive and water And pneumatically injecting the same by air pressure).

In the obtained multilayer glass ceramic substrate, shrinkage during firing is suppressed only in the thickness direction by the constrained inorganic green layer.
It can be suppressed to 5% or less, and the glass ceramic green sheet is uniformly and securely bonded over the entire surface by the larger constrained inorganic green layer, so that the constrained inorganic green layer is partially warped due to peeling or the like. And deformation can be prevented.

[0044]

EXAMPLES Hereinafter, the method of the present invention will be described in detail with reference to Examples, Comparative Examples and Test Examples, but the present invention is not limited to only the following Examples. <Example 1> SiO _2- as a glass ceramic component
_{Al 2 O 3 -MgO-B 2} O 3 -ZnO based glass powder 60 wt%, CaZrO ₃ powder 20 wt%, was used SrTiO ₃ powder 17 wt% and Al ₂ O ₃ powder 3 wt%. 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, 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.
Ethyl cellulose was kneaded as an organic binder using 5% by weight of a ZnO-based glass powder, and the viscosity was adjusted with terpineol to form an inorganic paste through a three-roll mill.

A predetermined number of the glass ceramic green sheets having a conductive pattern formed on the surface are stacked,
Pressure bonding was performed at a temperature of 55 ° C. and a pressure of 20 MPa to obtain a glass-ceramic green sheet laminate in which the vertical and horizontal dimensions in the lamination plane were each 200 mm.

Further, the above-mentioned inorganic paste was applied to the entire surface of both sides by printing and dried at 80 ° C. to obtain a glass ceramic green sheet laminate in which a constrained inorganic green layer having a thickness of 200 μm was adhered and laminated on both sides. .

The obtained laminate was placed on an alumina setter and heated in air at 500 ° C. for 2 hours to remove organic components, and then fired at 900 ° C. for 1 hour. After firing, the constrained inorganic layers were adhered to both surfaces of the glass ceramic substrate. In this state, the constrained inorganic layer did not peel off even if it was tapped lightly.

Most of the constrained inorganic layer 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 inorganic layer 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 the removal of the constrained inorganic layer was a smooth surface having a surface roughness Ra of 1 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> A glass ceramic substrate was obtained in the same manner as in Example 1 except that an inorganic paste using glass having a softening point of 600 ° C and 700 ° C was applied and a constrained inorganic green layer was laminated. Comparative Example 1 A glass ceramic substrate was obtained in the same manner as in Example 1 except that an inorganic paste containing no glass was applied and a constrained inorganic green layer was laminated. Comparative Example 2 A glass ceramic substrate was obtained in the same manner as in Example 1 except that an inorganic paste using glass having a softening point of 920 ° C. was applied and a constrained inorganic green layer was laminated. Comparative Example 3 A glass ceramic substrate was obtained in the same manner as in Example 1 except that an inorganic paste using glass having a softening point of 400 ° C. was applied and a constrained inorganic green layer was laminated.

As a result, the glass ceramic substrates obtained in Examples 2 and 3 had a shrinkage in the lamination plane of 0.5% or less (ie, a shrinkage of 99.5% or more) in the same manner as in Example 1.
No warping or deformation was observed on the substrate.

On the other hand, in the glass ceramic substrates obtained in Comparative Examples 1 and 2, the constrained inorganic green layer used did not contain glass or contained glass having a softening point higher than the firing temperature. In each case, the constrained inorganic green layer was easily peeled off from the fired glass ceramic substrate. In addition, since the bonding strength between the glass ceramic green sheet and the constrained inorganic green layer is weak, the shrinkage ratio in the laminated surface of the glass ceramic substrate is 85%.
The glass ceramic substrate was greatly deformed because only a part of the substrate was bonded to the constrained inorganic layer.

On the other hand, in Comparative Example 3, since the softening point of the glass contained in the constrained inorganic green layer was low, the organic component was not completely removed, so that shrinkage in the lamination plane of the glass ceramic substrate was 0.5% or less. However, the color tone of the glass ceramic substrate became gray. <Examples 4 to 7> SiO 2 was used as the 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 organic binder in 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 form a slurry. Using this slurry, a glass ceramic green sheet having a thickness of 300 μm was formed by a doctor blade method.

Next, 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.

On the other hand, Al ₂ O ₃ powder and a SiO ₂ —MgO—CaO—Al ₂ O ₃ glass powder having a softening point of 720 ° C. were used as inorganic components in the proportions shown in Table 1, respectively. An inorganic paste for forming was prepared.

A predetermined number of the glass ceramic green sheets having a conductive pattern formed on the surface are stacked,
Pressure bonding is performed at a temperature of 55 ° C. and a pressure of 20 MPa to obtain a glass-ceramic green sheet laminate in which the vertical and horizontal dimensions in the laminating plane are each 200 mm, and the above inorganic paste is screen-printed on the entire surface of both sides. And dried to obtain a laminate in which the constrained inorganic green layers were laminated.

The obtained laminate was placed on an alumina setter and heated in air at 500 ° C. for 2 hours to remove organic components, and then fired at 850 ° C. for 1 hour. Next, the constrained inorganic layer adhered to the surface of the glass ceramic substrate was removed. The surface of the obtained glass ceramic substrate had a surface roughness Ra of 1 μm.
m, and the conductor had no problem with solder wettability.

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.

[0060]

[Table 1]

From Table 1, it can be seen that each of the restrained inorganic grease of Examples 4 to 7 was
Glass-ceramic substrate obtained using the firing layer
Shrinkage and warpage are suppressed, with high dimensional accuracy
You can see that there is. <Test Example 1> (Shrinkage test of constrained inorganic green layer) Al as inorganic component
_TwoO_ThreePowder and SiO with softening point of 720 ℃_Two-MgO-CaO-A
l _TwoO_ThreeSystem glass powder and each in a predetermined ratio,
Addition of ethyl cellulose as organic binder
And adjust the viscosity with terpineol
To make an inorganic paste.

The inorganic paste is applied on a sintered Al ₂ O ₃ ceramic substrate by a screen printing method and dried to form a constrained inorganic green layer, and then heated at 500 ° C. in the air for 2 hours to remove organic components. After that, firing was performed at 850 ° C. for 1 hour.

FIG. 2 shows the relationship between the shrinkage ratio in the plane of the obtained constrained inorganic layer and the amount of glass added. In addition, the shrinkage rate shows a variation with the average value (n = 5) of the shrinkage rates in the in-plane direction of the laminated layer excluding the thickness direction of the constrained inorganic layer. ).

As shown in FIG. 1, in order to make the shrinkage rate 99.5% or more, that is, to suppress the shrinkage of the constrained inorganic layer to 0.5% or less, the amount of glass added to the constrained inorganic green layer is about 15% by weight or less. It is understood that it is desirable to make If the glass content exceeds 15% by weight, the variation in shrinkage tends to increase. However, when the amount of added glass is small, the constraint of the glass ceramic green sheet by the constrained inorganic green layer is reduced.
), It is necessary to determine the amount of glass that does not reduce the constraint, and the preferred range is 0.5 to 15% by weight in the present invention. <Test Example 2> SiO ₂ —Al ₂ O ₃ —MgO as glass
When the relationship between the amount of glass added and the shrinkage was examined in the same manner as in Test Example 1 except that -B ₂ O ₃ -ZnO-based glass powder was used, when the amount of glass added was 15% by weight or less, the restricted inorganic green layer was not used. Had a shrinkage of 99.5% or more, and maintained about 99.8% when the amount of glass added was 10% by weight or less.

[0065]

According to the present invention, a non-sinterable inorganic material, glass and an organic binder, which are bonded to the glass ceramic green sheet laminate and do not substantially shrink during firing, are provided on both surfaces of the glass ceramic green sheet laminate. Since the constrained inorganic green layer formed by applying and drying the inorganic paste containing it is laminated and fired, shrinkage in the laminated surface of the glass ceramic green sheet substrate can be reliably suppressed, and dimensional accuracy without warping or deformation There is an effect that a glass ceramic substrate having a high density can be obtained.

[Brief description of the drawings]

FIG. 1 is a graph showing the relationship between the amount of glass added to a constrained inorganic green layer and the shrinkage ratio.

Continued on front page F-term (reference) 4G030 AA07 AA08 AA09 AA16 AA17 AA32 AA35 AA36 AA37 AA61 BA09 BA12 BA21 CA03 CA08 GA27 GA32 4G055 AA08 AC09 BA22 5E346 AA12 AA15 AA24 AA38 BB01 CC18 CC32 CC38 CC39 GG30 GG03 GG02 HH11

Claims (5)

[Claims] A step of forming a glass ceramic green sheet laminate by laminating a plurality of glass ceramic green sheets each having an organic binder and having a conductive pattern formed on the surface thereof; A step of applying an inorganic paste containing a non-sinterable inorganic material, glass and an organic binder on both sides of the body and drying to form a constrained inorganic green layer; and the constrained inorganic green layer and a glass ceramic green sheet laminate Removing the organic component from the laminate, and then firing to produce a glass ceramic substrate holding the constrained inorganic layer; and removing the constrained inorganic layer from the glass ceramic substrate, wherein the constrained inorganic green The glass content of the layer is such that the constrained inorganic green layer Characterized in that the amount is such that the constrained inorganic green layer is not substantially shrunk in the lamination plane of the constrained inorganic green layer. 2. The method for producing a glass ceramic substrate according to claim 1, wherein the softening point of the glass contained in the constrained inorganic green layer is lower than the firing temperature of the glass ceramic green sheet laminate. 3. The method according to claim 1, wherein the glass contained in the constrained inorganic green layer has a softening point higher than a volatilization temperature of the organic component. 4. The glass content in the constrained inorganic green layer is 0.5 to 1 of the total inorganic components in the constrained inorganic green layer.
The method for producing a glass ceramic substrate according to claim 1, wherein the content is 5% by weight. 5. The method according to claim 1, wherein the thickness of the constrained inorganic green layer is 10% or more of the thickness of the glass ceramic green sheet laminate on one side.