KR100826405B1 - Constraining green sheet and manufacturing method of multi-layer ceramic substrate - Google Patents

Abstract

A constraining green sheet and a manufacturing method of a multi-layer ceramic substrate are provided to reduce a contraction rate and a residual carbon content. A constraining green sheet(25) includes a first constraining layer(25a) and a second constraining layer(25b). The first constraining layer has a surface positioned on a multi-layer ceramic substrate and is composed of a first organic binder(24a) and a first inorganic powder(22a). The first inorganic powder has a first grain size. The second constraining layer is bonded to a top surface of the first constraining layer and is composed of a second organic binder(24b) and a second inorganic powder(22b). The second inorganic powder has a second grain size larger than the first grain size. The second constraining layer has the same or a lower powder filling density in comparison with the first constraining layer.

Description

Constrained green sheet and manufacturing method of multilayer ceramic substrate using the same {CONSTRAINING GREEN SHEET AND MANUFACTURING METHOD OF MULTI-LAYER CERAMIC SUBSTRATE}

1 is a cross-sectional view showing an example of a conventional green sheet for restraint sinterability.

Figure 2 is a cross-sectional view showing a green sheet for the sinterability restraint according to an embodiment of the present invention.

3A to 3C are cross-sectional views of processes for explaining an example of a method of manufacturing a multilayer ceramic substrate according to the present invention.

<Code Description of Main Parts of Drawing>

22a, 42a: first inorganic powder particles 22b, 42b: second inorganic powder particles

24a, 44a: first organic material 24b, 44b: second organic material

25, 45: restraint green sheet 25a, 45a: first restraint layer

25b, 55b: second restraint layer 31: green multilayer ceramic substrate

31 ': sintered multilayer ceramic substrate

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a multilayer ceramic substrate, and more particularly, to a method for manufacturing a multilayer ceramic substrate using the same as the non-sintering constrained green sheet used to manufacture a low temperature co-fired substrate by a non-shrinkage process.

In general, the multilayer ceramic substrate using the glass-ceramic may implement an interlayer circuit having a three-dimensional structure and form a cavity, and thus may have various design elements with high design flexibility.

As a result, the utilization of multilayer ceramic substrates is gradually increasing in the miniaturized and highly functional high frequency component market. Initially, multilayer ceramic substrates were fabricated by forming circuit patterns and vias with conductive electrodes on ceramic green sheets, ordering lamination to desired thicknesses according to design, and firing. In this process, the ceramic substrate has a volume shrinkage of about 35 to 50%, and particularly, a shrinkage of about 12 to 17% in the transverse direction, that is, in the horizontal and vertical lengths, respectively. Since such lateral shrinkage is difficult to control uniformly, a dimensional error of about 0.5% occurs not only for each manufacturing order but also within the same manufacturing order.

As the structure of the multilayer ceramic substrate is compounded and refined, the design margin of the internal pattern and the via structure gradually decreases, so that a non-shrink firing process for suppressing the lateral shrinkage of the multilayer ceramic substrate is required.

To this end, a method of suppressing shrinkage in the x-y direction by bonding a flexible green sheet of a non-sinterable material which is not fired at the firing temperature of the ceramic substrate material to one or both surfaces of the multilayer ceramic substrate is used. In particular, a load is applied to prevent distortion of the substrate during firing. In this case, a lack of a passage for degreasing in the firing process may lower the firing characteristics. In addition, the amount of residual carbon in the sintered ceramic laminate may be large, which may cause a decrease in the reliability of the ceramic substrate.

Therefore, in order for the restraining green sheet to have sufficient restraining force, there is a need for a non-shrinkable material and a process for allowing the binder to be well removed during firing while being in close contact with the ceramic substrate.

As a conventional technique for debinding, Japanese Patent Laid-Open No. 7-30253 discloses that even when using a restraining green sheet, a hole is formed in the restraining green sheet so that sufficient binder removal occurs in the internal ceramic substrate, A technique for facilitating debinding is described by filling a hole with a resin that is easier to decompose than an organic binder included. However, this method suffers from the burden of the additional process of forming a hole in the constraint layer and the possibility of deformation of the body due to the hole.

In addition, in Korean Patent Laid-Open Publication No. 2002-0090296, by using an organic binder having a lower thermal decomposition initiation temperature than an organic binder of a green body sheet for the restraining green sheet, the binder of the restraining green sheet is first removed and is generated as a result. A method for smoothly discharging the binder of the green body layer through the closed passage is proposed. However, in order to maximize the restraint of the restraint green sheet, it is necessary to refine the powder of the restraint layer and increase the content to maximize the contact point between the restraint layer and the ceramic laminate. In this case, the pores inside the restraint green sheet may not be sufficiently secured. Can be. If the pores are not sufficiently secured, even though the organic material of the restraint green sheet is first decomposed, it is difficult for the binder decomposed or burned from the ceramic laminate to move out of the thickness by several hundred microns through the pores inside the restraint green sheet, It is difficult to expect a sufficient effect.

In addition, in Japanese Laid-Open Publication No. 2006-173456, as shown in Fig. 1, the volume content of the organic binder 14 and the inorganic powder particles 12 of the restraining green sheet 15 corresponds to the microcrystalline multilayer ceramic substrate 11. The close contact surface 15a with the contact surface is larger than the close contact surface 15b, that is, the inclination of the organic content is generated between the contact surface and the free surface, thereby increasing the bonding force between the ceramic substrate and the restraint layer and confining many pores. A method is proposed that facilitates binder removal towards the free surface of the layer.

However, since the density gradient of the components through sedimentation is formed in the restraining green sheet 15 using the doctor blade method, it is very difficult to ensure the reproducibility of the appropriate thickness and volume content of each region. In addition, the method uses an inorganic powder having a large particle size (e.g., more than twice the particle size of the ceramic substrate) in order to reduce the amount of the organic binder at the bottom of the powder particles easily settle to the bottom surface when forming the restraint green sheet, Not only is it difficult to secure enough contact points with the ceramic substrate, but there is a problem that it is difficult to increase the capillary force that can move the organic binder from the ceramic substrate to the restraining green sheet.

In order to solve the above-described prior art problem, an object of the present invention is to provide a restraining green sheet that can be in close contact with the ceramic substrate for the body to ensure a smooth debinding during firing while maintaining a sufficient restraining force.

Another object of the present invention is to provide a method of manufacturing a multilayer ceramic substrate in which the residual amount of carbon is reduced while the shrinkage ratio is sufficiently suppressed by using the above-mentioned restraining green sheet.

In order to solve the above technical problem, an aspect of the present invention,

A non-sintering constrained green sheet for disposing on a top surface and / or a bottom surface of a green multilayer ceramic substrate, the green sheet having a surface to be disposed on the multilayer ceramic substrate, the first inorganic powder having a first organic binder and a first particle size. And a second inorganic powder bonded to an upper surface of the first constraint layer, the second inorganic binder having a second particle size larger than the first particle size, and the same as the powder filling density of the first constraint layer. Provided is an incombustibility restraining green sheet including a second restraint layer having a powder filling density of less than or less than that.

Preferably, the first inorganic powder of the first restraint layer may have an average particle size of 0.5 to 1.5 times the particle size of the inorganic powder of the green ceramic substrate to have a sufficient contact point with the green ceramic substrate.

Preferably, the second inorganic powder of the second restraint layer has an average particle size corresponding to 2 to 5 times the particle diameter of the first inorganic powder of the first restraint layer so that the passage for the binder is more easily ensured. Can be.

In order to facilitate bonding of the first and second constraint layers, the first and second organic binders may be the same organic binder. Even in this case, the second organic binder content ratio to the total weight of the second restraint layer is equal to the first organic binder to the total weight of the first restraint layer so that the passage for the binder is sufficiently secured inside the second restraint layer. It is preferable that it is lower than the content ratio of.

The thickness of the first constraint layer preferably has a thickness of 0.8 to 1.2 times the thickness of the second constraint layer so that desired functions of the first and second constraint layers can be properly expressed.

According to another aspect of the present invention, there is provided a step of providing a green multilayer ceramic substrate in which a plurality of low-temperature fired green sheets are stacked; And firing the non-sintered multilayer ceramic substrate in a state where the non-sinterable restraint green sheet is disposed, and removing the resultant of the non-sinterable restraint green sheet from the fired multilayer ceramic substrate. The non-sintering constraining green sheet may be formed on the first constraining layer and the first constraining layer made of a first inorganic binder having a first organic binder and a first inorganic powder and in contact with the multilayer ceramic substrate. 2 composed of an organic binder and a second inorganic powder having a second particle size larger than the first particle size, which is equal to or lower than the powder filling density of the first restraint layer. It provides a method for manufacturing a multilayer ceramic substrate consisting of the second constraint layer having a powder filling density.

Preferably, the arranging the green sintering restraint green sheet may be a step of arranging the green sintering restraint green sheet on both top and bottom surfaces of the microcrystalline multilayer ceramic substrate.

Hereinafter, with reference to the accompanying drawings will be described embodiments of the present invention;

Figure 2 is a cross-sectional view showing a green sheet for the sinterability restraint according to an embodiment of the present invention.

As shown in Fig. 2, the green sheet 25 for the sinterability restraint according to the present embodiment includes a first restraint layer 25a that provides a bonding surface disposed on a green multilayer ceramic substrate (not shown) and thereon. The formed second constraint layer 25b is included. The first constraint layer 25a includes a first inorganic powder 22a having a first average particle diameter and a first organic binder 24b. The second constraint layer 22b includes a second inorganic powder 22b and a second organic binder 24b having a second average particle diameter larger than the first average particle diameter. The second constraint layer 25b has a powder filling density equal to or lower than that of the first constraint layer 25a.

Since the first constraint layer 25a includes powder having a relatively low particle size, the first constraint layer 25a may have a sufficient contact point with the green multilayer ceramic substrate, and an effective shrinkage suppression effect may be expected at the time of firing. In this aspect, the first inorganic powder 22a of the first constraint layer 25a preferably has an average particle size corresponding to 0.5 to 1.5 times the particle size of the inorganic powder of the green ceramic substrate.

In addition, since the second constraint layer 25b includes a relatively large particle size, a passage for the binder may be easily ensured. In order to sufficiently obtain such an effect, preferably, the second inorganic powder of the second constraint layer 25b corresponds to 2 to 5 times the particle diameter of the first inorganic powder 22a of the first constraint layer 25a. It can have an average particle size.

In general, the restraining force for suppressing the shrinkage in the plane direction of the ceramic substrate is mainly due to the bonding force generated by penetration of the sinterable inorganic binder component into the restraining green sheet. Therefore, as in the present invention, when the inorganic powder 22a of the first constraint layer 25a is fine, a greater bonding force is ensured, and the contact point with the ceramic substrate can be increased. In addition, the capillary force is increased through this process so that the organic binder in the ceramic substrate can easily penetrate into the first constraint layer 25a and be removed through the second constraint layer 25b having a relatively large binder path. .

In addition, the first and second constraint layers 25a and 25b may be manufactured and bonded through a separate process. The bonding process may be made in advance and provided as one green sheet 25. Alternatively, the lamination can be performed in a separate ceramic layer on a green ceramic substrate in sequence, without applying a separate bonding step, and then bonded at the time of hot pressing applied before firing (see invention example below). Whatever the manufacturing method, because of the powder particle diameter difference between the first restraint layer 25a and the second restraint layer 25b, mechanical coupling such as unevenness is easily mutually increased, thereby increasing the planar restraint force.

Further, the first and second organic binders 24a and 24b may be the same organic binder so that easier bonding between the first and second constraint layers 25a and 25b is ensured. In addition to the organic binder, an organic additive such as a dispersant may be added. Here, the passage for the debinder depends on this residual organic content (wt%). "Residual organic content" may be defined as the weight of the organic matter including the organic binder to the total inorganic powder weight, and is inversely proportional to the powder packing density described above. Assuming that the general organic additive is added at about the same level, in order to more sufficiently ensure the passage for the binder in the second restraint layer 25b, the second organic to the total weight of the second restraint layer 25b The content ratio of the binder 24b is preferably lower than the content ratio of the first organic binder 24a to the total weight of the first constraint layer 25b.

In addition, the thickness of the first constraint layer preferably has a thickness of 0.8 to 1.2 times the thickness of the second constraint layer so that desired functions of the first and second constraint layers can be properly expressed. It doesn't happen. That is, the thicknesses of the first and second restraint layers may be designed by appropriately changing the thickness according to the conditions (thickness, shrinkage rate or organic binder content) of the green ceramic substrate to be fired.

3A to 3C are cross-sectional views of processes for explaining an example of a method of manufacturing a multilayer ceramic substrate according to the present invention.

First, as shown in Fig. 3A, a microcrystalline multilayer ceramic substrate 31 in which a plurality of low-temperature firing green sheets 31a-31e are stacked is prepared. The green sheets 31a to 31e may be manufactured through a suitable known process including organic materials such as glass-ceramic powder for sintering and organic binder capable of low temperature firing. In each of the green sheets 31a to 31e, electrode patterns 32 and conductive via holes 34 necessary for interlayer circuit configuration are formed. Subsequently, a plurality of green sheets 31a to 31e may be stacked to provide the microcrystalline multilayer ceramic substrate 31 as shown in FIG. 3A.

Next, as shown in FIG. 3B, the green sheet 45 for the non-sintering restraint is disposed on the upper and lower surfaces of the green multilayer ceramic substrate 31, and the green multilayer ceramic substrate 31 is fired in this state. The green sheet 45 for the sinterability restraint may be understood with reference to the matter of FIG. 2. That is, the restraining green sheet 45 includes a first restraint layer 45a disposed on the green multilayer ceramic substrate 31 and a second restraint layer 45b formed thereon. The first constraint layer 45a includes a first inorganic powder 42a having a first average particle diameter and a first organic binder 44b, and the second constraint layer 42b is larger than the first average particle diameter. A second inorganic powder 42b and a second organic binder 44b having a second average particle diameter are included. Here, the second constraint layer 45b has a powder filling density equal to or lower than that of the first constraint layer 45a.

The restraining green sheet 45 may be disposed on only one surface of the upper and lower surfaces of the ceramic substrate. However, the restraining green sheet 45 may be disposed on both sides for effective shrinkage suppression. In addition, the first and second constraint layers 45a and 45b may be disposed on the ceramic substrate 31 in a state where the first and second restraint layers 45a and 45b are bonded to one layer through separate processes. Without lamination to the green ceramic substrate 31 as a separate layer, in turn, it can be joined in the hot pressing applied before firing.

As shown in FIG. 3C, the resultant material of the hard burnability restraint green sheet 45 is removed from the fired multilayer ceramic substrate 31 '. After firing, the green sintering restraint 45 is de-binded and left in a powder state, and thus can be simply removed. As shown in Fig. 3C, the fired multilayer ceramic substrate 31 'is contracted in the thickness direction, but the shrinkage can be suppressed by the restraining green sheet 45 in the plane direction, that is, in the horizontal direction.

As such, the surface shrinkage of the multilayer ceramic substrate 31 ensures a high bonding force and an increased contact point by the first restraint layer 25a composed of fine powder to maintain the shrinkage suppression effect, and at the same time, increase the capillary force to the ceramic. The organic binder in the substrate 31 can easily penetrate into the first constraint layer 45a and be removed through the second constraint layer 45b having a relatively large binder path.

In the conventional restraint layer for the non-shrinkage process, the two problems of the shrinkage suppression effect and the debinding effect have not been effectively solved, but in the manufacturing method of the multilayer ceramic substrate according to the present invention, a separate manufacturing process By providing two restraining layers having different powder grain sizes, the binder of the ceramic substrate was realized while effectively suppressing the planar shrinkage. As described above, the first restraint layer is a layer in direct contact with the ceramic substrate. The powder has a fine particle diameter, which increases the contact point with the ceramic substrate, and the capillary force for the binder in the ceramic substrate penetrates toward the first restraint layer to form a bond. To increase the effect. As a result, a strong bond of a large area with the ceramic substrate can be formed to strongly suppress the planar shrinkage of the ceramic substrate. In addition, the second restraint layer may be configured to have a relatively large inorganic powder particle size and a low binder content as the outermost layer stacked on the first restraint layer, thereby ensuring a relatively large amount of pores around the powder. As a result, the binder penetrated into the first constraint layer may be effectively removed from the second constraint layer. In addition, due to the difference in powder particle diameter between the first constraint layer and the second constraint layer, mechanical coupling such as unevenness between each other is easy, thereby increasing the planar constraint force.

As described below, a multilayer ceramic substrate was prepared, and a restraining green sheet (Invention Example 1-2) corresponding to the conditions of the present invention and a restraining green sheet (Comparative Example 1-4) outside the conditions of the present invention were prepared and fired. The process was carried out.

[ Smile  Fabrication of Multilayer Ceramic Substrate]

15 wt% of an acrylic binder and 0.5 wt% of a dispersant were added to the glass-ceramic powder, and a mixed solvent of toluene and ethanol was added, followed by dispersion using a ball mill. The slurry thus obtained was filtered and degassed, and a green sheet having a thickness of 50 µm was formed by using a doctor blade method. The green sheet was cut to a predetermined size, and a predetermined electrode pattern was formed by screen printing, and then 20 layers were pressed and laminated to prepare an integrated microcrystalline multilayer ceramic laminate.

In order to compare the effect according to the type of binder in the ceramic substrate, in addition to the acrylic binder, using a PVB-based binder was prepared a multi-layered multilayer ceramic laminate in the same manner as described above.

[Manufacture of Green Sheets for Restraint]

Table 1 below shows the constraint layer type conditions for the invention and comparative examples. According to the conditions, the constraint layer required for each invention example and a comparative example was manufactured as follows.

( Inventive Example )

As a restraining green sheet corresponding to the conditions of the present invention, a restraining green sheet having the following first and second restraining layers was manufactured. According to Inventive Examples 1 and 2 shown in Table 1 below, the first restraint layer part was prepared by adding 15 wt% of an acrylic binder and 0.5 wt% of a dispersant to an alumina powder having an average particle diameter of 1.5 μm, and a mixed solvent of toluene and ethanol. Then, it was dispersed using a ball mill. The slurry thus obtained was filtered through a filter and degassed, and a green sheet having a thickness of 100 µm was formed by using a doctor blade method (Invention Examples 1 and 2). The second constrained layer portion was dispersed by using a ball mill after adding 15 wt% of an acrylic binder and 0.5 wt% of a dispersant to an alumina powder having an average particle diameter of 4 μm, and adding a mixed solvent of toluene and ethanol. The slurry thus obtained was filtered through a filter and degassed, and a green sheet having a thickness of 100 μm was formed by using a doctor blade method (Invention Example 1). In addition, the second restraint layer part was further prepared by varying the acrylic binder to 12 wt% under the same conditions (Invention Example 2).

( Comparative example )

Further, for comparative experiments, as in the comparative example conditions of Table 1, the restraint green sheet having a thickness of 100 μm was formed by changing the average particle diameter of the alumina powder. As shown in Table 1 below, Comparative Examples 1 and 2 were prepared using alumina powders having the same particle diameters (1.5 μm and 4 μm, respectively). The powder particle diameter (4 μm) of the first constraint layer to be contacted was prepared using an alumina powder larger than the powder particle size (1.5 μm) of the second constraint layer.

Powder particle size (㎛) Binder Content (wt%) First constraint layer Second constraint layer First constraint layer Second constraint layer Inventive Example 1 1.5 4 15 15 Inventive Example 2 1.5 4 15 12 Comparative Example 1 1.5 1.5 15 15 Comparative Example 2 4 4 15 15 Comparative Example 3 4 1.5 15 15

 [Adhesion between Ceramic Substrate and Restraint Green Sheet]

 Two 100 μm thick restraint green sheets cut to the same area as the green ceramic substrate were attached to each of the two main surfaces of the green ceramic substrate (first and second restraint layers in the case of the invention), and 300 kgf / ㎠ , Thermocompression bonding was carried out under the condition of 85 ℃ to prepare an integrated laminate.

As described in Table 1, two layers of each layer prepared as described above were used. Particularly, Examples 1 and 2 of the present invention used a combination of powder particles and first and second restraint layers having different organic contents. This experiment was carried out on two types of ceramic substrates each using an acrylic binder and a PVB binder.

 [ Talbinder  And sintering]

 From room temperature to 420 ° C. in which organic matter decomposition takes place, the temperature was raised at a rate of 60 ° C. per hour, and maintained at 420 ° C. for 2 hours to ensure sufficient debinder time. After binder removal, the temperature was raised to 300 ° C. per hour to reach a calcination temperature of 870 ° C., followed by holding at 870 ° C. for 30 minutes to allow sintering. After completion of sintering, the mixture was cooled to room temperature to obtain a sintered body.

 The restraining green layer was removed from the sintered body thus obtained, and the shrinkage ratio and the amount of residual carbon of the ceramic substrate were measured. Table 2 below shows the firing results of the ceramic substrate by the combination of constraint layers under each condition.

Acrylic binder PVB Binder Residual carbon [ppm] Shrinkage [%] Residual carbon [ppm] Shrinkage [%] Inventive Example 1 59 0.26 111 0.31 Inventive Example 2 41 0.27 86 0.31 Comparative Example 1 91 0.26 124 0.32 Comparative Example 2 56 0.38 105 0.41 Comparative Example 3 57 0.36 107 0.40

Referring to Comparative Example 1 of Table 2, when both the first constraint layer and the second constraint layer are made of fine powder, the shrinkage constraint is strong due to the increase of the contact point with the ceramic substrate and the increase of the capillary force. There was not enough passage for the remaining quantity. In addition, Comparative Example 2 was relatively low in residual coal, but due to the use of powder having a large particle size, the shrinkage suppression force of the ceramic substrate was weak, and thus the shrinkage ratio was high. On the other hand, the shrinkage of the ceramic substrate was low in Comparative Examples 1, 1 and 2, in which the powder particle diameter of the first restraint layer in contact with the ceramic substrate was small.

In addition, when comparing the invention examples 1 and 2, the binder content in the second constraint layer did not have a critical effect. This is because the shrinkage suppression effect is ensured by the first constraint layer rather than the second constraint layer. However, in terms of residual carbon after firing, the binder content of the second constrained layer tended to be lower than that of Inventive Example 2, which is low. This is because the second restraint layer of Inventive Example 2 has a lower residual organic content than the second restraint layer of Inventive Example 1 to more effectively ensure the passage to the binder.

As a result, the invention example using the second restraint layer having a high particle size and a low binder content so that the powder of the first restraint layer is fine and the binder is fine so that the restraint force on the ceramic substrate is strong as intended in the present invention. 3 showed the most improved results.

It is intended that the invention not be limited by the foregoing embodiments and the accompanying drawings, but rather by the claims appended hereto. Accordingly, various forms of substitution, modification, and alteration may be made by those skilled in the art without departing from the technical spirit of the present invention described in the claims, which are also within the scope of the present invention. something to do.

As described above, according to the present invention, it is possible to realize a smooth binder removal of the ceramic substrate while effectively suppressing the planar shrinkage rate by providing first and second restraint layers having different powder sizes through separate manufacturing processes. In addition, it is possible to provide a green sheet having excellent reproducibility compared to the prior art of providing a distribution gradient according to precipitation of one powder particle size, and furthermore, the first constraint layer and the second constraint manufactured separately as in the present invention. Even if the layer is used, the mechanical particle size, such as irregularities, is easy due to the difference in the particle size of the powder between the two layers, thereby doubling the planar restraint force so that it can be stably used as one constraint green sheet.

Claims (13)

In the green sheet for the non-sinterability restraint for arranging on at least one of the upper surface and the lower surface of the microcrystalline multilayer ceramic substrate, A first restraint layer having a surface to be disposed on the multilayer ceramic substrate, the first restraint layer comprising a first organic binder and a first inorganic powder having a first particle size; It is bonded to the upper surface of the first restraint layer, the second organic binder and the second inorganic powder having a second particle size larger than the first particle size, the powder filling density equal to or lower than the powder filling density of the first restraint layer. Green stiffness for restraint including a second restraint layer having a. The method of claim 1, The first inorganic powder of the first restraint layer has an average particle size of 0.5 to 1.5 times the particle size of the inorganic powder of the green ceramic substrate, characterized in that the green sheet for the sinter constrained restraint. The method according to claim 1 or 2, And the second inorganic powder of the second constraint layer has an average particle size corresponding to 2 to 5 times the particle diameter of the first inorganic powder of the first constraint layer. The method of claim 1, The first and second organic binder is a green sheet for restraint sinterability characterized in that the same organic binder. The method of claim 4, wherein The second organic binder content ratio to the total weight of the second restraint layer is less than the content ratio of the first organic binder to the total weight of the first restraint layer characterized in that the green sheet for restraint. The method of claim 1, The thickness of the first restraint layer has a thickness of 0.8 to 1.2 times the thickness of the second restraint layer, characterized in that the green sheet for sinter constrained restraint. Providing a green multi-layered ceramic substrate having a plurality of low-temperature fired green sheets stacked thereon; Disposing a green sheet for constraining the sinterability on at least one of an upper surface and a lower surface of the microcrystalline multilayer ceramic substrate; Firing the microcrystalline multilayer ceramic substrate in a state where the green sintering restraint green sheet is disposed; And Removing the resultant of the incombustibility restraint green sheet from the calcined multilayer ceramic substrate, The non-sintering constrained green sheet may be formed on the first constrained layer, the first constrained layer comprising a first organic binder and a first inorganic powder having a first particle size, and in contact with the multilayer ceramic substrate. A multilayer comprising a binder and a second inorganic powder having a second particle size greater than the first particle size, and a second confining layer having a powder filling density equal to or lower than that of the first confining layer. Ceramic substrate manufacturing method. The method of claim 7, wherein The disposing the green sintering constrained green sheet may include disposing the green sintering constrained green sheet on both top and bottom surfaces of the microcrystalline multilayer ceramic substrate. The method of claim 7, wherein The first inorganic powder of the first restraint layer has a mean particle size of 0.5 to 1.5 times the particle size of the inorganic powder of the green ceramic substrate. The method according to claim 7 or 9, The second inorganic powder of the second restraint layer has a mean particle size of 2 to 5 times the particle size of the first inorganic powder of the first restraint layer. The method of claim 7, wherein Wherein the first and second organic binders are the same organic binder. The method of claim 11, The second organic binder content ratio to the total weight of the second constraint layer is lower than the content ratio of the first organic binder to the total weight of the first constraint layer. The method of claim 7, wherein The thickness of the first constraint layer has a thickness of 0.8 to 1.2 times the thickness of the second constraint layer manufacturing method of the multilayer ceramic substrate.

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