JP2013098325A - Method for manufacturing multilayer ceramic substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for manufacturing a multilayer ceramic substrate capable of suppressing shrinkage dispersion by enhancing adhesion between a green sheet laminate and a shrinkage suppression sheet in the case of using the shrinkage suppression sheet to perform non-shrinkage burning.SOLUTION: Since a shrinkage factor of a shrinkage suppression sheet 23 in a planar direction is small, being ≤0.05% in a degreasing process, a shrinkage factor of a green sheet laminate 31 in the degreasing process and a subsequent burning process becomes small, and shrinkage dispersion also becomes small. Since the shrinkage factor of the shrinkage suppression sheet 23 in the degreasing process is larger than the shrinkage factor of the green sheet laminate 31, adhesion between the shrinkage suppression sheet 23 and the green sheet laminate 31 is improved. Thus, the shrinkage of the green sheet laminate 31 can be suppressed. Since the shrinkage dispersion can be suppressed, a dimensional variation in a multilayer ceramic substrate 5 can be reduced.

Description

  The present invention relates to a method for manufacturing a multilayer ceramic substrate having high dimensional accuracy, for example, a substrate capable of mounting a test terminal for an electronic component such as an IC on a surface layer with high accuracy and sufficiently withstanding repeated measurement. The present invention relates to a method for manufacturing a multilayer ceramic substrate, which can be degreased and fired with high dimensional accuracy in manufacturing a substrate having such a thickness as to have strength.

  In recent years, there has been a growing demand for electrical inspection of ICs, which are electronic components, in units of silicon wafers. In particular, the current trend toward larger silicon wafers requires the handling of wafers with a diameter of 300 mm (12 inches). Yes.

  Further, when inspecting these silicon wafers, it is necessary to form connection terminals that contact IC pads (IC pads) on the IC inspection substrate of the measuring jig, and these connection terminals are repeatedly contacted. Therefore, strength is required.

  In order to satisfy these requirements, a multilayer ceramic substrate is used as an IC inspection substrate. However, in the conventional normal manufacturing method, due to shrinkage variation during firing of the ceramic substrate, connection to an IC pad is possible. Obtaining the required dimensional accuracy is not easy.

Therefore, in recent years, a non-shrinkage firing technique has been developed as a method of manufacturing a ceramic substrate that requires such dimensional accuracy.
This non-shrinkage firing technology is a method of laminating a restraint sheet (shrinkage suppression sheet) made of a ceramic sheet that does not sinter at the temperature at which the green sheet laminate is fired on the upper and lower surfaces of the green sheet laminate in which the green sheets are laminated. When fired, the shrinkage-suppressing sheet suppresses shrinkage in the XY direction (plane direction) during firing of the green sheet laminate, thereby realizing high dimensional accuracy. In this non-shrinkage baking technique, instead of suppressing the shrinkage in the XY direction, the shrinkage is greatly made in the Z direction.

  Regarding this shrinkage suppression sheet, various proposals have been made in Patent Documents 1 to 4. For example, Patent Document 1 discloses a technique in which the particle size of inorganic particles in the shrinkage suppression sheet is 1.5 to 7 times the particle size of inorganic particles contained in low-temperature sintered ceramics (LTCC). Patent Document 2 discloses a technique in which a carrier film surface of a shrinkage suppression sheet is pressure-bonded so as to be in contact with an LTCC laminate. Patent Document 3 discloses a technique of using a flat plate-like inorganic particle in the shrinkage suppression sheet. Patent Document 4 discloses a technique of adding glass to a shrinkage suppression sheet.

JP 2006-173456 A Japanese Patent Laying-Open No. 2005-310913 JP-A-2005-277107 JP 2002-16360 A

  By the way, when using such a non-shrinkage firing technique, the shrinkage suppression sheet itself is fired in order to bond the shrinkage suppression sheet to the upper and lower surfaces of the green sheet laminate and suppress firing shrinkage in the XY direction. Of course, it is necessary to reduce the amount of shrinkage even at the time of degreasing prior to firing, and in the process from the degreasing to firing, the shrinkage-suppressing sheet has an appropriate frictional force and adhesive strength. It is important that it is bonded to the sheet laminate.

  However, in the above-described conventional technology, various studies have been made on the shrinkage suppression sheet, but nothing has been studied on the amount of shrinkage of the shrinkage suppression sheet during degreasing and the adhesion due to the shrinkage.

  Therefore, the adhesion between the green sheet laminate and the shrinkage suppression sheet is not sufficient during non-shrinkage firing, and as a result, the shrinkage state of the green sheet laminate is not constant (even if fired under the same conditions). There was a variation. In other words, the variation in shrinkage rate may be large.

If this variation in shrinkage rate is large, a multilayer ceramic substrate with high dimensional accuracy cannot be obtained. Therefore, a measure for suppressing the variation in shrinkage rate is important.
The present invention has been made in view of the above problems, and when performing non-shrinkage firing using a shrinkage suppression sheet, the adhesion between the green sheet laminate and the shrinkage suppression sheet can be increased, thereby shrinking. It is an object of the present invention to provide a method for manufacturing a multilayer ceramic substrate that can suppress variation in rate.

  (1) As a first aspect, the present invention provides a multilayer ceramic substrate having a plurality of ceramic layers laminated and an interlayer connection conductor portion (via conductor after firing) that conducts in the thickness direction of the ceramic layer. In the method, a first step of laminating a plurality of green sheets having interlayer connection conductor forming portions (via conductors before firing) to be the interlayer connection conductor portions after firing to form a green sheet laminate, and the green sheet lamination A second step of forming a green composite laminate by laminating a shrinkage suppression sheet not sintered at a temperature at which the green sheet laminate is sintered on at least one surface of the body, and degreasing the green composite laminate A third step of forming a green composite laminate after degreasing, a fourth step of firing the green composite laminate after degreasing to form a ceramic laminate, A fifth step of removing an unsintered layer of the shrinkage suppression sheet remaining on the surface of the ceramic laminate after the formation, and in the third step, the shrinkage rate in the planar direction of the shrinkage suppression sheet is 0. 0.05% or less, and the shrinkage rate in the planar direction of the shrinkage suppression sheet is larger than the shrinkage rate in the planar direction of the green sheet laminate.

  In the first aspect, in the third step, which is a degreasing step, the shrinkage rate in the planar direction of the shrinkage suppression sheet (hereinafter sometimes simply referred to as the shrinkage rate) is as small as 0.05% or less, so the third step and ( The shrinkage rate of the green sheet laminate in the fourth step (which is a subsequent firing step) is reduced.

  That is, if the shrinkage rate of the shrinkage suppression sheet is small during degreasing, the shrinkage rate of the green sheet laminate that is in close contact with the shrinkage suppression sheet is also reduced, and thus the shrinkage rate of the green sheet laminate including subsequent firing is reduced. Becomes smaller.

And if the shrinkage rate of this green sheet laminated body is small, the variation in shrinkage rate will also become small.
In other words, the green sheet laminate shrinks when fired, but when producing a large number of green sheet laminates, the degree of shrinkage (shrinkage rate) is not necessarily constant even if the materials and production conditions are constant. There will be some variation. At this time, if the shrinkage rate during firing of the green sheet laminate is large, the variation is also amplified and increased. However, in the first aspect, the shrinkage rate of the green sheet laminate itself is small, so the variation is also reduced.

  Moreover, in this 1st aspect, as typically shown in FIG. 1, the shrinkage rate of the shrinkage | contraction suppression sheet | seat (X) in a 3rd process is larger than the shrinkage rate of a green sheet laminated body (Y). In the figure, the direction of the arrow indicates the direction of contraction, and the size of the arrow indicates the degree (size) of contraction.

  Thereby, at the time of degreasing, since a shrinkage | contraction suppression sheet | seat moderately bites into the surface of a green sheet laminated body, and moderate compressive stress generate | occur | produces, the adhesiveness of a shrinkage | contraction suppression sheet | seat and a green sheet laminated body improves.

  Therefore, when firing after degreasing, the shrinkage suppression sheet can be firmly adhered without peeling from the green sheet laminate, and the shrinkage of the green sheet laminate can be suppressed. Therefore, also by this, the variation in shrinkage rate can be suppressed.

  That is, if there is a variation in shrinkage ratio, naturally, there is a variation in dimensions in the fired ceramic laminate (and hence the multilayer ceramic substrate). However, in this first embodiment, the variation in shrinkage rate can be suppressed, so the multilayer ceramic substrate. It is possible to reduce the dimensional variation in.

  As described above, according to the first aspect, when non-shrinkage firing is performed using a shrinkage suppression sheet, the adhesion between the green sheet laminate and the shrinkage suppression sheet can be increased, thereby causing shrinkage variation. As a result, a multilayer ceramic substrate with high dimensional accuracy can be obtained.

  For example, according to the first aspect, a multi-layer having high dimensional accuracy that can be used for an electronic component inspection substrate such as an IC and having high strength (for example, having a thickness of 2 mm or more). There is a remarkable effect that the ceramic substrate can be easily manufactured.

  The variation in dimensions in the multilayer ceramic substrate includes not only variations in the outer dimensions of the multilayer ceramic substrate but also variations in the positions of via conductors formed on the multilayer ceramic substrate (for example, distances between via conductors).

  (2) In the present invention, as a second aspect, the shrinkage suppression sheet contains a resin and a plasticizer in addition to the ceramic material as a main component, and the resin and the plasticizer are added to the entire shrinkage suppression sheet. In a range of 25% to 36% by volume.

  When the ratio of the total amount of the resin and the plasticizer is less than 25% by volume, the dimensional shrinkage rate during degreasing is reduced, but the sheet moldability becomes difficult and a shrinkage suppression sheet is temporarily prepared. However, the adhesiveness with the green sheet is deteriorated.

On the other hand, when the ratio of the total amount of the resin and the plasticizer exceeds 36% by volume, the dimensional shrinkage rate at the time of degreasing the shrinkage suppression sheet may exceed 0.05%.
Therefore, in the second aspect, as described above, the ratio of the total amount of the resin and the plasticizer is set in the range of 25 volume% to 36 volume%.

  Here, although a ceramic material is used as a main component for the shrinkage suppression sheet, the particle diameter (D50) of the ceramic is preferably in the range of 1 μm to 5 μm. That is, when the particle diameter is less than 1 μm, the amount of resin or plasticizer necessary for sheet molding increases, and it may be difficult to mold the sheet at the optimum ratio described above. Further, if the particle diameter exceeds 5 μm, the number of contacts with the green sheet laminate after degreasing decreases, and it may be difficult to sufficiently suppress the shrinkage of the green sheet laminate during firing.

(3) As a third aspect of the present invention, the shrinkage suppression sheet does not contain a glass component.
In this third aspect, since the shrinkage-suppressing sheet does not contain a glass component, the glass component does not adhere to the ceramic laminate during firing. Therefore, when removing the unsintered layer of the shrinkage-suppressing sheet after firing, The unsintered layer can be easily removed.

  In addition, as a material of the green sheet which comprises the said green sheet laminated body, a well-known ceramic (main component), resin, and a plasticizer are mentioned. Among these, as the ceramic, glass, a mixture of glass and an inorganic filler (alumina, mullite, cordierite, quartz glass, zirconia, etc.) can be employed. As the resin, an acrylic resin, a butyral resin, or the like can be used. As the plasticizer, a phthalic acid-based or adipic acid-based ester compound can be used.

  Moreover, as a material of the said shrinkage | contraction suppression sheet | seat, a known ceramic (main component), resin, and a plasticizer are mentioned. Of these, alumina, mullite, magnesia, silicon nitride, or the like can be used as the ceramic. Further, as the resin and the plasticizer, the same material as that of the green sheet can be used.

It is explanatory drawing explaining the principle of this invention. It is sectional drawing of the multilayer ceramic substrate manufactured by the manufacturing method of the multilayer ceramic substrate of this embodiment. It is a top view which shows a part of surface of the board | substrate for electronic component inspection. It is explanatory drawing which shows the usage method of the board | substrate for electronic component inspection. It is explanatory drawing which shows a part of manufacturing method of the multilayer ceramic substrate of embodiment. It is explanatory drawing which shows a part of manufacturing method of the multilayer ceramic substrate of embodiment. It is a top view which shows arrangement | positioning of the sheet | seat and hole which are used for experiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[Embodiment]
a) First, a specific example of a multilayer ceramic substrate manufactured by the method of manufacturing a multilayer ceramic substrate according to this embodiment will be described with reference to FIGS.

Here, as the multilayer ceramic substrate, a substrate used as an electrical inspection substrate for an electronic component such as an IC will be described as an example.
As shown in FIG. 2, an electronic component inspection substrate 1 includes a multilayer ceramic substrate 5 (for example, a rectangular parallelepiped sintered body having a length of 100 mm × width of 100 mm × thickness of 5 mm) in which a plurality of ceramic layers 3 are laminated in the thickness direction. And an electrode (pad) 7 formed on the surface of the multilayer ceramic substrate 5.

The ceramic layer 3 is made of, for example, a low temperature fired glass ceramic obtained by firing a mixture of a glass component and a ceramic component at a low temperature of about 800 to 1050 ° C., for example.
Specifically, each ceramic layer 3 is made of a glass ceramic whose main component is mullite and borosilicate glass, and SiO, Al ₂ O ₃ and B ₂ O _{3 are} contained in the borosilicate glass.

  Moreover, the said electrode 7 is formed in the front and back of the multilayer ceramic substrate 5, This electrode 7 has the structure which laminated | stacked Ti / Cu / Ni / Au layer in order. Therefore, a large number of electrodes 7 are exposed on the surface of the multilayer ceramic substrate 5 (see FIG. 3).

Further, an internal wiring layer 9 is formed inside the multilayer ceramic substrate 7 (specifically, a boundary portion between the ceramic layers 3).
Then, an interlayer connection conductor portion (via conductor) 11 extending in the thickness direction of the substrate is provided so as to electrically connect the electrode 7 on the front surface and the electrode 7 on the back surface of the multilayer ceramic substrate 5 via the internal wiring layer 9. Is formed.

  Note that Ti, Cr, Mo, Cu, Ni, Au, and a combination thereof can be adopted as the conductor constituting the electrode 7, and the conductor constituting the internal wiring layer 7 and the via conductor 9 is glass ceramic. A conductor such as Ag, an Ag / Pt alloy, or an Ag / Pd alloy that can be simultaneously fired at a low temperature during firing can be used.

  Also, as shown in FIG. 4, a conductive probe (connection terminal) 13 is connected to the electrode 7 on the multilayer ceramic substrate 5 having the above-described configuration, and an electronic component inspection jig (for electrical inspection of a silicon wafer). Jig) 15 is formed.

  The electronic component inspection jig 15 corresponds to, for example, a φ300 mm (12 inch) silicon (Si) wafer 17, and the probe 13 contacts the terminal 19 of the IC in the silicon wafer 17 (before cutting out each IC). By doing so, it is possible to inspect a large number of ICs at a time.

b) Next, a specific example of the method for manufacturing the multilayer ceramic substrate 5 of the present embodiment will be described in detail with reference to FIGS.
In this embodiment, in the degreasing step, the shrinkage rate in the planar direction of the shrinkage suppression sheet is 0.05% or less, and the shrinkage rate in the planar direction of the shrinkage suppression sheet is less than the shrinkage rate in the planar direction of the green sheet laminate. It is characterized in that a large one is used. In addition, the ratio of the resin and the plasticizer used in the shrinkage suppression sheet is in the range of 25 volume% to 36 volume% with respect to the entire shrinkage suppression sheet, and the material of the shrinkage suppression sheet does not include a glass component. There are features. Details will be described below.

<Manufacture of green sheets>
As shown in FIG. 5A, first, as a raw material powder for forming a ceramic layer 3 made of glass ceramic, a borosilicate glass powder mainly composed of SiO ₂ , Al ₂ O ₃ , and B ₂ O _3. (Average particle diameter: 3 μm, specific surface area: 1.0 m ² / g) and mullite powder (average particle diameter: 3 μm, specific surface area: 3.0 m ² / g) were prepared.

  In addition to the raw material powder, an acrylic binder is used as a binder component (resin component), and a plasticizer component is provided as a plasticizer component that gives an appropriate flexibility to the green sheet after molding in order to form a green sheet to be the ceramic layer 3. Di-Ocicle Phthalate) and MEK (methyl ethyl ketone) were prepared as a solvent for imparting appropriate slurry viscosity and sheet strength.

  Next, the borosilicate glass powder and the mullite powder were weighed to a weight ratio of 50:50 and a total amount of 1 kg, and placed in an alumina pot. A ceramic slurry was obtained by adding 120 g of the acrylic resin (binder) and appropriate amounts of a plasticizer (DOP) and a solvent (MEK) to the pot and mixing them for 5 hours.

Using the obtained ceramic slurry, a green sheet (ceramic green sheet for low-temperature firing) 21 having a thickness of 0.15 mm was obtained by a doctor blade method.
<Manufacture of shrinkage suppression sheet>
Separately from the step of producing the green sheet 21, an alumina powder having an average particle size of 3 μm and a specific surface area of 1 m ² / g was prepared as a ceramic raw material powder in order to produce the shrinkage suppression sheet 23.

Furthermore, an acrylic binder was prepared as a binder component during sheet formation, DOP as a plasticizer component, and MEK as a solvent.
As in the case of the green sheet 21, 1 kg of alumina powder is put into an alumina pot, 80 g of acrylic resin and 40 g of plasticizer (DOP) are added, and a necessary amount of solvent (MEK) is added. And mixed for 3 hours to obtain a slurry.

Using this slurry, a shrinkage suppression sheet 23 having a thickness of 0.30 mm was produced by the doctor blade method as shown in FIG.
<Manufacture of multilayer ceramic substrate>
Next, as shown in FIG. 5C, a through hole (through hole) 25 was formed in the green sheet 21 by punching.

Next, as shown in FIG. 5D, the through hole 25 was filled with a conductive paste to form an interlayer connection conductor forming portion 27 (to be the interlayer connection conductor portion 11 after firing).
This conductive paste for the interlayer connection conductor part 11 is obtained by adding resin to a powder raw material in which 5 parts by weight of a borosilicate glass powder having a softening point of 800 ° C. is added to 100 parts by weight of silver powder having an average particle size of 3.5 μm. In addition to the addition of ethyl cellulose resin, terpineol was added as a solvent and kneaded in a three-roll mill.

  Next, as shown in FIG. 5 (e), the surface of the green sheet 21 is printed by using a conductive paste so as to cover the surface of the interlayer connection conductor forming portion 27 and the like (later with the internal wiring layer 9). A wiring pattern (printing pattern) 29 which is a conductor pattern was formed.

  This conductive paste for the internal wiring layer 9 is prepared by adding 2 parts by weight of a borosilicate glass powder having a softening point of 700 ° C. to 100 parts by weight of silver powder having an average particle size of 0.9 μm as a resin. It is prepared by adding ethyl cellulose resin, adding terpineol as a solvent, and kneading with a three-roll mill.

-Next, as shown in FIG.5 (f), each green sheet 21 was laminated | stacked and the green sheet laminated body 31 was formed.
Next, as shown in FIG. 6A, the shrinkage suppression sheets 23 were laminated on both sides of the green sheet laminate 31 to form a green composite laminate 33.

  Next, as shown in FIG. 6 (b), degreasing at 300 ° C. for 600 minutes in a firing furnace (not shown) having a press mechanism, and after degreasing, a green composite laminate (not shown) Subsequently, this degreased green composite laminate was fired at 900 ° C. for 60 minutes while applying a pressing force of 0.2 MPa from both sides in the laminating direction, as shown in FIG. An unsintered shrinkage suppression sheet 23 remains on the surface of the laminated body 35), thereby obtaining a composite laminated sintered body 37.

  Next, as shown in FIG. 6C, the (unsintered) shrinkage suppression sheet 23 remaining on both main surfaces of the composite laminated sintered body 37 is removed by an ultrasonic cleaner using water as a medium. As a result, a ceramic laminate 35 was obtained.

Next, as shown in FIG. 6D, both outer surfaces of the ceramic laminate 35 were polished by lapping using alumina abrasive grains.
Next, as shown in FIG. 6E, for example, a Ti thin film is formed by sputtering at a position corresponding to the interlayer connection conductor portion 11 on the surface of the polished ceramic laminate 35 (that is, the multilayer ceramic substrate 5). Later, Cu plating, Ni plating, and Au plating were sequentially performed to form an electrode 7 to complete the electronic component inspection substrate 1.

c) Next, the effect of this embodiment will be described.
In the present embodiment, in the degreasing step, the shrinkage rate in the planar direction of the shrinkage suppression sheet 23 is as small as 0.05% or less, so the shrinkage rate of the green sheet laminate 31 in the degreasing step and the subsequent firing step is small. As a result, shrinkage variation is also reduced.

  In the present embodiment, the shrinkage rate of the shrinkage suppression sheet 23 in the degreasing step is larger than the shrinkage rate of the green sheet laminate 31. Thereby, at the time of degreasing, since the shrinkage | suppression suppression sheet 23 bites into the green sheet laminated body 31 moderately and moderate compressive stress generate | occur | produces, the adhesiveness of the shrinkage | suppression suppression sheet 23 and the green sheet laminated body 31 improves. .

  Therefore, when baking after degreasing, the shrinkage | contraction suppression sheet | seat 23 can contact | adhere firmly, without peeling from the green sheet laminated body 31, and can suppress the shrinkage | contraction of the green sheet laminated body 31. FIG. Therefore, the shrinkage variation can be suppressed also by this. As a result, dimensional variations in the multilayer ceramic substrate 5 can be reduced.

  As described above, according to the present embodiment, when non-shrinkage firing is performed using the shrinkage suppression sheet 23, the adhesion between the green sheet laminate 31 and the shrinkage suppression sheet 23 can be increased, thereby reducing shrinkage variation. Generation | occurrence | production can be suppressed and, as a result, the multilayer ceramic substrate 1 with a high dimensional accuracy can be obtained.

  Therefore, the multi-layer ceramic substrate 5 having high dimensional accuracy that can be used for the electronic component inspection substrate 1 and also having strength (for example, having a thickness of 2 mm or more) can be easily manufactured. Has an effect.

  Moreover, in this embodiment, since the ratio of the resin and the plasticizer in the shrinkage suppression sheet 23 is 25% by volume or more with respect to the entire shrinkage suppression sheet 23, the sheet moldability is easy, and the green sheet 21 and Good adhesion. And since the ratio of the total amount of resin and a plasticizer is 36 volume% or less, the dimensional shrinkage rate at the time of degreasing of the shrinkage | contraction suppression sheet 23 can be easily made into 0.05% or less.

Moreover, in this embodiment, since the glass component is not included in the shrinkage suppression sheet 23, the glass component does not adhere to the ceramic laminate 31 during firing. When removing, the unsintered layer can be easily removed.
<Experimental example>
Next, experimental examples conducted for confirming the effects of the present invention will be described.

(1) Experimental example 1
In this Experimental Example 1, the shrinkage ratio between the green sheet and the shrinkage suppression sheet in the degreasing process is examined.

  First, five samples each of green sheets and shrinkage suppression sheets used in the experiment were manufactured by the same manufacturing method as in the above embodiment. The size of the green sheet is 125 mm long × 125 mm wide × 0.15 mm thick, and the size of the shrinkage suppression sheet is 125 mm long × 125 mm wide × 0.3 mm thick.

  Specifically, the composition of the green sheet is the same as that of the above embodiment, but for the shrinkage suppression sheet, as shown in Table 1 below, the amount of components of the resin and the plasticizer is changed, and the sample within the scope of the present invention. (Examples 1 to 3) and samples outside the scope of the present invention (Comparative Examples 1 to 3) were produced. In addition, Examples 1-3 satisfy | fill the conditions of Claims 1-3.

  Further, as shown in FIG. 7, holes of 0.5 mm in diameter (H) were formed in each sample sheet. Specifically, a square having a side of 100 mm is set at the center in the plane direction of the sheet of each sample (so that the distance from the outer periphery is 12.5 mm), and each vertex of the square and the inside of each side are set. I made a hole in the point.

And the sheet | seat of each sample was degreased at 500 degreeC for 2 hours, and the fluctuation | variation rate (shrinkage rate) of the pitch between holes before and behind degreasing was calculated | required.
Specifically, in each sample, the average of the pitches A to F (see FIG. 7) between the holes of the five sheets after degreasing was obtained, and the shrinkage ratio with respect to the value before degreasing (100 mm) was obtained. The results are shown in Table 1 below.

(2) Experimental example 2
In Experimental Example 2, the shrinkage ratio of the pitch between holes of the green sheet laminate in the degreasing step and the firing step and the variation in the pitch between holes in the substrate (ceramic laminate) after firing were examined.

  First, samples of a green sheet and a shrinkage suppression sheet used for the experiment were manufactured by the same manufacturing method as in the above embodiment. The size of the green sheet is 125 mm long × 125 mm wide × 0.15 mm thick, and the size of the shrinkage suppression sheet is 125 mm long × 125 mm wide × 0.3 mm thick.

  Specifically, in the same manner as in Experimental Example 1, with respect to the shrinkage suppression sheet, as shown in Table 1 below, the component amounts of the resin and the plasticizer were changed, and samples within the scope of the present invention (Examples 1 to 3). ) And samples outside the scope of the present invention (Comparative Examples 1 to 3).

Further, in the same manner as in Experimental Example 1, holes with diameters of 0.5 mm were formed in the green sheet.
And 20 green sheets were laminated | stacked, the green sheet laminated body was formed, and the pitch between holes was measured. Five green sheet laminates were prepared for each sample.

  Next, as in the above-described embodiment, a shrinkage suppression sheet is disposed on both sides of the green sheet laminate, and after degreasing by heating at 300 ° C. for 600 minutes, the obtained degreased green composite laminate is reduced to 0.00. While pressurizing with a load of 2 MPa, firing was performed at 900 ° C. for 60 minutes to produce a ceramic laminate of each sample.

And the pitch between holes of this ceramic laminated body was measured, and the variation rate (shrinkage rate) of the pitch between holes by degreasing and firing was obtained.
Specifically, in each sample, an average (average of 5) of the pitches A to F (see FIG. 7) between the holes of the ceramic laminate after degreasing and firing is obtained, and the green sheet laminate before degreasing and firing is obtained. The shrinkage rate with respect to the value was obtained. The results are shown in Table 1 below.

Further, in each sample, the pitch between holes of all five ceramic laminates was measured, and the variation in pitch between holes (dimensional variation) was also obtained. The results are shown in Table 1 below.
This dimensional variation is a standard deviation (standard deviation (%) of shrinkage rate of each ceramic laminate).

Note that “◯” in Table 1 indicates that no peeling occurred.
As is apparent from Table 1, in Examples 1 to 3 within the scope of the present invention, the shrinkage rate in the degreasing of the shrinkage suppression sheet is 0.05% or less, and the shrinkage rate in the degreasing of the shrinkage suppression sheet is a green sheet. Is larger than the shrinkage rate in degreasing, and therefore, the adhesion between the shrinkage-suppressing sheet and the green sheet is large, and therefore the shrinkage rate (and hence the shrinkage variation) of the green sheet (and hence the green sheet laminate) is small. It can be seen that the dimensional variation in the body (and hence the multilayer ceramic substrate) is small.

  On the other hand, in Comparative Examples 1 and 2, the shrinkage rate in the degreasing of the shrinkage suppression sheet is as large as 0.054% and 0.069%, so the adhesion between the shrinkage suppression sheet and the green sheet is small, and thus the green sheet lamination It can be seen that the shrinkage rate of the body (and thus the shrinkage variation) is large, and as a result, the dimensional variation in the multilayer ceramic substrate is large.

Further, in Comparative Example 3, the shrinkage rate in the degreasing of the shrinkage suppression sheet is as large as 0.087%, which is not preferable because the shrinkage suppression sheet peels off during firing.
In addition, this invention is not limited to the said embodiment and Example at all, and it cannot be overemphasized that it can implement with a various aspect in the range which does not deviate from this invention.

(1) For example, a shrinkage suppression sheet may be disposed only on one side of the green laminate.
(2) Moreover, it is not necessary to pressurize at the time of baking.

DESCRIPTION OF SYMBOLS 1 ... Board | substrate for electronic component inspection 3 ... Ceramic layer 5 ... Multilayer ceramic substrate 7 ... Electrode 9 ... Internal wiring layer 11 ... Interlayer connection conductor part (via conductor)
DESCRIPTION OF SYMBOLS 21 ... Green sheet 23 ... Shrinkage suppression sheet 27 ... Interlayer connection conductor formation part 31 ... Green sheet laminated body 33 ... Green composite laminated body 35 ... Ceramic laminated body

Claims (3)

In the method for manufacturing a multilayer ceramic substrate having a plurality of ceramic layers laminated and an interlayer connection conductor portion conducting in the thickness direction of the ceramic layer,
A first step of laminating a plurality of green sheets having an interlayer connection conductor forming portion that becomes the interlayer connection conductor portion after firing to form a green sheet laminate;
A second step of forming a green composite laminate by laminating a shrinkage suppression sheet not sintered at a temperature at which the green sheet laminate is sintered on at least one surface of the green sheet laminate;
Degreasing the green composite laminate, and forming a green composite laminate after degreasing;
A fourth step of firing the green composite laminate after degreasing to form a ceramic laminate;
After the firing, a fifth step of removing the unsintered layer of the shrinkage suppression sheet remaining on the surface of the ceramic laminate,
With
In the third step, the shrinkage rate in the planar direction of the shrinkage suppression sheet is 0.05% or less, and the shrinkage rate in the planar direction of the shrinkage suppression sheet is the shrinkage rate in the planar direction of the green sheet laminate. A method for producing a multilayer ceramic substrate, which is larger.   The shrinkage suppression sheet contains a resin and a plasticizer in addition to the ceramic material as a main component, and contains the resin and the plasticizer in a range of 25% by volume to 36% by volume with respect to the entire shrinkage suppression sheet. The method for producing a multilayer ceramic substrate according to claim 1.   The said shrinkage | contraction suppression sheet | seat does not contain a glass component, The manufacturing method of the multilayer ceramic substrate of Claim 1 or 2 characterized by the above-mentioned.

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