JP2020157649A - Sheet member and method of manufacturing ceramic substrate - Google Patents

Abstract

To provide a sheet member which allows a good ceramic substrate to be manufactured and a method of manufacturing a ceramic substrate.SOLUTION: A sheet member 1 is arranged between ceramic green sheets 20P containing a first binder resin when ceramic substrates 20 are manufactured. The sheet member 1 comprises ceramic particles, carbon particles, and a second binder resin different from the first binder resin. The thermal decomposition temperature of the second binder resin is lower than that of the first binder resin.SELECTED DRAWING: Figure 3

Description

The present invention relates to a method for manufacturing a sheet member and a ceramic substrate, and specifically, relates to a sheet member arranged between ceramic green sheets when manufacturing a ceramic substrate, and a method for manufacturing a ceramic substrate using the sheet member. ..

A ceramic substrate can be mentioned as an example of a substrate on which electronic components are mounted. The manufacturing process of such a ceramic substrate includes a firing step of firing a raw sheet called a ceramic green sheet to obtain a ceramic substrate. In general, the time required for the ceramic substrate manufacturing process tends to depend on the time required for this firing process. Therefore, in order to shorten the manufacturing period of the ceramic substrate, a plurality of ceramic green sheets may be laminated and the laminated ceramic green sheets may be fired at one time. However, in this case, there is a concern that the laminated ceramic substrates are fused at the time of firing, and the ceramic substrates are cracked when the fused ceramic substrates are peeled off, resulting in deterioration of the ceramic substrate.

Therefore, for example, as described in Patent Document 1 below, the firing step may be performed after arranging a sheet member containing ceramic particles having a high melting point between the laminated ceramic green sheets. According to such a method, since the sheet member is interposed between the laminated ceramic green sheets, it is said that fusion of ceramic substrates can be suppressed.

Japanese Unexamined Patent Publication No. 9-77564

However, in the method for manufacturing a ceramic substrate as described in Patent Document 1, the sheet member is thermally deformed during the firing step, and the shape of the main surface of the sheet member is distorted due to this thermal deformation. Tend. If the shape of the main surface of such a sheet member is transferred to the main surface of the ceramic green sheet during the firing process, the shape of the main surface of the sintered ceramic substrate can be distorted, and a defective ceramic substrate is manufactured. Can be done.

Therefore, an object of the present invention is to provide a sheet member and a method for manufacturing a ceramic substrate, which can make it possible to manufacture a good ceramic substrate.

In order to achieve the above object, the present invention is a sheet member arranged between ceramic green sheets containing a first binder resin when a ceramic substrate is manufactured, and the ceramic particles, carbon particles, and the first binder are used. A second binder resin different from the binder resin is provided, and the thermal decomposition temperature of the second binder resin is lower than the thermal decomposition temperature of the first binder resin.

Further, in order to achieve the above object, the method for manufacturing the ceramic substrate of the present invention is different from the plurality of ceramic green sheets containing the first binder resin, the ceramic particles, the carbon particles, and the first binder resin. A preparatory step for preparing at least one sheet member having a binder resin and having a thermal decomposition temperature of the second binder resin lower than the thermal decomposition temperature of the first binder resin, and a ceramic green sheet to be laminated. A laminate forming step of arranging the sheet members between them to form a ceramic green sheet laminate, a firing step of firing the ceramic green sheet laminate to form a ceramic substrate laminate, and a ceramic substrate laminate. It is characterized by comprising a peeling step of peeling the ceramic substrate from the ceramic substrate.

In the present specification, the thermal decomposition temperature means a temperature at which the weight of the sample becomes 90 wt% in thermogravimetric analysis (TG: Thermogravimetry), where the weight of the sample at the start of measurement is 100 wt%.

As a result of diligent research on the above-mentioned problem that the ceramic substrate becomes defective due to thermal deformation of the sheet member, the inventors have found the following points. That is, when the thermal decomposition temperature of the first binder resin contained in the ceramic green sheet and the thermal decomposition temperature of the second binder resin contained in the sheet member are substantially the same, the sheet member is placed between the ceramic green sheets. When the arranged ceramic green sheet laminate is fired, the first binder resin and the second binder resin can be softened almost at the same time. In this case, the shape of the main surface of the sheet member distorted by the softening of the second binder resin can be easily transferred to the main surface of the ceramic green sheet which is easily deformed by the softening of the first binder resin. Therefore, the shape of the main surface of the ceramic substrate obtained by firing the ceramic green sheet can be distorted.

On the other hand, the binder resin of the sheet member of the present invention is formed from a second binder resin having a thermal decomposition temperature lower than the thermal decomposition temperature of the first binder resin contained in the ceramic green sheet. Further, in the method for manufacturing a ceramic substrate of the present invention, a sheet member having such a second binder resin is arranged between ceramic green sheets. Therefore, according to the method for manufacturing the sheet member of the present invention and the ceramic substrate of the present invention, the softening of the second binder resin starts before the softening of the first binder resin when the ceramic green sheet laminate is fired. That is, at this stage when the second binder resin begins to soften, the first binder resin does not soften as much as the second binder resin, so that the ceramic green sheet is less likely to be deformed than the sheet member. Therefore, it is possible to prevent the shape of the distorted main surface of the sheet member from being transferred to the main surface of the ceramic green sheet. Therefore, according to the method for manufacturing the sheet member and the ceramic substrate of the present invention, the sintered ceramic substrate is compared with the case where the thermal decomposition temperature of the first binder resin and the thermal decomposition temperature of the second binder resin are substantially the same. The shape of the main surface of the surface can be suppressed from being distorted, and a good ceramic substrate can be produced.

The difference between the thermal decomposition temperature of the first binder resin and the thermal decomposition temperature of the second binder resin is preferably 10 ° C. or higher and 100 ° C. or lower.

When the difference between the thermal decomposition temperature of the first binder resin and the thermal decomposition temperature of the second binder resin is 10 ° C. or more, the difference between the thermal decomposition temperature of the first binder resin and the thermal decomposition temperature of the second binder resin is 0. Since there is a difference between the thermal decomposition temperature of the first binder resin and the thermal decomposition temperature of the second binder resin as compared with the case where the temperature is larger than ° C and smaller than 10 ° C, the ceramic is formed at the stage when the sheet member starts to soften. Green sheets tend to be more resistant to deformation. Therefore, the transfer of the distorted shape of the main surface of the sheet member to the ceramic green sheet can be suppressed more effectively. On the other hand, when the difference between the thermal decomposition temperature of the first binder resin and the thermal decomposition temperature of the second binder resin is 100 ° C. or less, the difference between the thermal decomposition temperature of the first binder resin and the thermal decomposition temperature of the second binder resin is Compared with the case where the temperature is higher than 100 ° C., thermal decomposition and thermal shrinkage of the sheet member due to warm air of the coater used at the time of manufacturing the sheet member can be suppressed, and the manufactured sheet member can be made flatter. Therefore, by using such a sheet member having good flatness, a better ceramic substrate can be manufactured.

In this case, the difference between the thermal decomposition temperature of the first binder resin and the thermal decomposition temperature of the second binder resin may be 25 ° C. or higher and 60 ° C. or lower.

In this case, it is possible to more effectively suppress the shape of the main surface of the ceramic substrate from becoming distorted.

As described above, according to the present invention, there is provided a sheet member and a method for manufacturing a ceramic substrate, which can make it possible to manufacture a good ceramic substrate.

It is a perspective view which shows typically the sheet member of this invention. It is a flowchart which shows the manufacturing method of the ceramic substrate of this invention. It is a figure which shows the state of the laminated body forming process schematicly. It is a figure which shows the state of the ceramic substrate laminated body formed by a firing process schematicly. It is a figure which shows the state of the peeling process roughly. It is a graph which shows the thermal decomposition temperature of the 1st binder resin and the 2nd binder resin.

Hereinafter, embodiments for carrying out the method for manufacturing the sheet member and the ceramic substrate according to the present invention will be illustrated together with the accompanying drawings. The embodiments illustrated below are for facilitating the understanding of the present invention, and are not for limiting the interpretation of the present invention. The present invention can be modified or improved from the following embodiments without departing from the gist thereof. In the drawings referred to below, the dimensions of each member may be changed for ease of understanding.

The sheet member of the present invention can be used for manufacturing a ceramic substrate, as will be described later. Specifically, as will be described later, the sheet member of the present invention can be arranged between the ceramic green sheets to be laminated in the method for manufacturing a ceramic substrate in which the ceramic green sheets are laminated and fired.

Here, before explaining the sheet member in detail, first, the ceramic green sheet will be described.

The ceramic green sheet is a raw sheet that becomes a ceramic sintered body by firing. Such a ceramic green sheet can be produced, for example, as follows. First, a predetermined ceramic powder, a predetermined sintering aid, a first binder resin as a binder resin, a predetermined solvent, a predetermined plasticizer, and the like are mixed in a predetermined blending amount to prepare a slurry. Next, the prepared slurry is molded into a flat sheet by a method such as a doctor blade method or a calendar roll method to prepare a single-layer ceramic green sheet. The ceramic green sheet can also be produced by filling a molding machine with raw material powder and pressure molding.

The ceramic powder for preparing the slurry is not particularly limited, but aluminum oxide, aluminum nitride, or a compound of aluminum oxide and silicon dioxide may be used. Further, as the first binder resin, for example, an acrylic resin, a polyvinyl butyral (PVB) resin, or the like can be used. The blending amount of the first binder resin in the slurry is not particularly limited, but may be, for example, 4.0 wt% to 10.0 wt%.

Next, the seat member of the present invention will be described in detail.

FIG. 1 is a perspective view schematically showing the seat member 1 of the present invention. As shown in FIG. 1, the sheet member 1 has a thin plate-like outer shape. In the present embodiment, for example, the length W of the main surfaces 10 and 11 of the sheet member 1 in the longitudinal direction is approximately 80 mm, and the length L of the main surfaces 10 and 11 in the vertical direction perpendicular to the longitudinal direction is approximately 80 mm. It is set to 70 mm. The thickness H of the sheet member 1 is, for example, approximately 0.07 mm.

The sheet member 1 contains ceramic particles, carbon particles, and a second binder resin as a binder resin.

As the ceramic particles, for example, aluminum oxide, aluminum nitride, or a compound of aluminum oxide and silicon dioxide can be used. The average particle size of the ceramic particles is not particularly limited, but for example, those having an average particle size of 0.1 μm to 20.0 μm measured by a laser diffraction / scattering method can be used.

The carbon particles are not particularly limited, and for example, carbon particles having an average particle diameter of 20.0 μm to 30.0 μm measured by a laser diffraction / scattering method can be used.

The second binder resin is a resin different from the first binder resin of the ceramic green sheet, and as the second binder resin, for example, an acrylic resin or the like can be used. Further, as the acrylic resin, for example, methacrylic butadiene styrene resin, methyl methacrylate resin, or the like can be used.

It should be noted that the above-mentioned "different resins" include not only resins having different series but also resins of the same series, for example, the composition, the type of functional group bonded to the main chain, the presence or absence of an auxiliary agent added, and the addition. Contains resins with different types of auxiliaries. As described above, the second binder resin is a resin different from the first binder resin. Therefore, even if both the first binder resin and the second binder resin are acrylic resins, the second binder resin is added, for example, with respect to the composition, the type of functional group bonded to the main chain, the presence or absence of an auxiliary agent, and the addition. The type of auxiliary agent used is different from that of the first binder resin. Therefore, even if the first binder resin and the second binder resin are of the same series, the characteristics of these resins, such as the thermal decomposition temperature, may differ.

Such a second binder resin has a thermal decomposition temperature lower than the thermal decomposition temperature of the first binder resin. The thermal decomposition temperature of the second binder resin is, for example, the difference between the thermal decomposition temperature of the first binder resin and the thermal decomposition temperature of the second binder resin from the viewpoint of producing a good ceramic substrate by the method for producing a ceramic substrate described later. Is preferably 10 ° C. or higher and 100 ° C. or lower, and for example, the above difference may be 25 ° C. or higher and 60 ° C. or lower.

The weight average molecular weight of the second binder resin is not particularly limited, but is preferably 800,000 to 1,500,000, preferably 900,000 to 1,500,000 from the viewpoint of improving the quality of the sheet member 1 produced in the manufacturing process of the sheet member 1, which will be described later. 10,000 to 1.1 million is more preferable.

Next, a method for manufacturing a ceramic substrate using the sheet member 1 of the present invention will be described. In this embodiment, a method for manufacturing a ceramic substrate made of alumina ceramics will be described.

FIG. 2 is a flowchart showing a method of manufacturing a ceramic substrate using the sheet member 1. As shown in FIG. 2, this method for manufacturing a ceramic substrate includes a preparation step P1, a laminate forming step P2, a firing step P3, and a peeling step P4.

<Preparation process P1>
First, this step is performed. This step is a step of preparing the sheet member 1 and the ceramic green sheet.

The sheet member 1 can be manufactured, for example, as follows. First, a dispersion liquid containing ceramic particles, the second binder resin, carbon particles, and a dispersant is prepared. As the ceramic particles, as described above, aluminum oxide, aluminum nitride, or a compound of aluminum oxide and silicon dioxide may be used, and the blending amount in the dispersion is, for example, 0.1 wt% to 20.0 wt%. May be. The weight average molecular weight of the second binder resin is not particularly limited, but as described above, it is preferably 800,000 to 1,500,000, more preferably 900,000 to 1,100,000. Further, the blending amount of the second binder resin in the dispersion liquid may be, for example, 20.0 wt% to 40.0 wt%. The dispersant is not particularly limited, but for example, sorbitan sesquiolate or the like can be used, and the blending amount in the dispersion liquid may be, for example, 0.4 wt% to 1.6 wt%.

Then, the sheet member 1 can be produced by applying this dispersion liquid in a sheet shape with a coater and drying it. At this time, if the weight average molecular weight of the second binder resin is 800,000 to 1,500,000, the dispersion may be too stretched when the dispersion is applied with the coater, or the dispersion may stick to the coater. Is suppressed, and a better sheet member 1 can be produced. If the weight average molecular weight of the second binder resin is 900,000 to 1.1 million, it is more likely that the dispersion liquid will not stretch too much or stick to the coater when the dispersion liquid is applied with the coater. A better sheet member 1 can be produced.

The obtained sheet member 1 may be cut to a desired size using a mold. For example, as described above, the length W of the main surfaces 10 and 11 in the longitudinal direction is approximately 80 mm, the length L of the main surfaces 10 and 11 in the vertical direction is approximately 70 mm, and the thickness H of the sheet member 1 is approximately 0. The sheet member 1 may be manufactured so as to have a thickness of .07 mm.

In addition, a ceramic green sheet is prepared in this step. As described above, this ceramic green sheet is prepared by appropriately mixing aluminum oxide powder, a sintering aid, the first binder resin, a solvent, a plasticizer, etc., and then using the prepared slurry by the doctor blade method or the like. It can be produced by molding into a flat sheet by a method such as a calendar roll method.

The ceramic green sheet may be manufactured so that the dimensions of the main surface are the same as those of the sheet member 1. For example, the ceramic green sheet may be produced so that the dimensions of the main surface are approximately 80 mm × 70 mm and the thickness is, for example, 0.1 mm to 1.0 mm.

<Laminate body forming step P2>
Next, this step is performed. This step is a step of arranging the sheet member between the ceramic green sheets to be laminated to form a ceramic green sheet laminate.

FIG. 3 is a diagram schematically showing the state of this process. As shown in FIG. 3, in this step, the ceramic green sheet 20P made in the preparation step P1 is superposed on at least one of the main surfaces 10 and 11 of the sheet member 1 made in the preparation step P1. In this way, the ceramic green sheet laminated body 30P formed by arranging the sheet member 1 between the ceramic green sheets 20P to be laminated is formed. In FIG. 3, in the preparation step P1, the sheet member 1 and the ceramic green sheet 20P are arranged so that the dimensions of the main surfaces 10 and 11 of the sheet member 1 and the dimensions of the main surface of the ceramic green sheet 20P are substantially the same. An example in which was made is shown.

<Baking process P3>
Next, this step is performed. This step is a step of firing the ceramic green sheet laminate 30P to form a ceramic substrate laminate. As described above, when the ceramic substrate produced by this production method is made of alumina ceramics, the aluminum oxide of the ceramic green sheet 20P in the ceramic green sheet laminate 30P is fired at a predetermined temperature at which it can be sintered. The predetermined temperature is, for example, a temperature of about 1400 ° C to 1600 ° C.

As described above, the thermal decomposition temperature of the second binder resin is lower than the thermal decomposition temperature of the first binder resin. Therefore, in this step, the softening of the second binder resin of the sheet member 1 starts before the softening of the first binder resin of the ceramic green sheet 20P.

Therefore, when the ceramic green sheet laminate 30P is fired, first, the second binder resin begins to soften, and the sheet member 1 begins to be thermally deformed. After that, softening of the first binder resin begins. After a further lapse of time, the first binder resin, sintering aid, solvent, plasticizer, etc. of the ceramic green sheet 20P disappeared and ceramic particles remained, and the remaining ceramic particles were sintered to obtain ceramic green. The sheet 20P serves as a ceramic substrate. Further, the second binder resin, carbon particles, dispersant and the like of the sheet member 1 disappear, and ceramic particles remain. In this way, as shown in FIG. 4, the ceramic substrate laminate 30 in which the ceramic particles of the sheet member 1 are interposed between the sintered ceramic substrates 20 is formed.

<Peeling process P4>
Next, this step is performed. This step is a step of peeling the ceramic substrate 20 from the ceramic substrate laminate formed in the firing step P3.

As described above, the ceramic particles derived from the sheet member 1 are interposed between the ceramic substrates 20 of the ceramic substrate laminate 30. Therefore, in the firing step P3, the ceramic green sheets 20P laminated via the ceramic particles of the sheet member 1 are kept separated from each other, and the ceramic green sheets 20P are prevented from being fused to each other. In FIG. 4, since the size of the ceramic particles derived from the sheet member 1 is extremely small with respect to the size of the ceramic substrate 20, it is shown that the laminated ceramic substrates 20 are in contact with each other. Is separated from the ceramic substrate 20 via the ceramic particles derived from the sheet member 1. Therefore, in this step, as shown in FIG. 5, the ceramic substrate 20 can be easily peeled off from the ceramic substrate laminate 30, and the ceramic substrate 20 is cracked or damaged when the ceramic substrate 20 is peeled off from the ceramic substrate laminate 30. It is suppressed.

As described above, a plurality of ceramic substrates 20 can be manufactured from one ceramic green sheet laminate 30P through the preparation step P1, the laminate forming step P2, the firing step P3, and the peeling step P4.

As described above, the sheet member 1 of the present embodiment is a sheet member arranged between the ceramic green sheets containing the first binder resin when the ceramic substrate is manufactured, and the ceramic particles, the carbon particles, and the first A second binder resin different from the first binder resin is provided, and the thermal decomposition temperature of the second binder resin is lower than the thermal decomposition temperature of the first binder resin.

Further, the method for manufacturing the ceramic substrate of the present embodiment includes a plurality of ceramic green sheets 20P containing the first binder resin, ceramic particles, carbon particles, and a second binder resin different from the first binder resin. Then, the sheet member 1 is between the preparatory step P1 for preparing at least one sheet member 1 whose thermal decomposition temperature of the second binder resin is lower than the thermal decomposition temperature of the first binder resin and the ceramic green sheet 20P to be laminated. From the laminate forming step P2 for forming the ceramic green sheet laminate 30P, the firing step P3 for firing the ceramic green sheet laminate 30P to form the ceramic substrate laminate 30, and the ceramic substrate laminate 30. It is characterized by comprising a peeling step P4 for peeling the ceramic substrate 20.

When the ceramic green sheets are directly laminated without interposing a sheet member, the directly laminated ceramic green sheets are likely to be fused to each other in the firing step. Therefore, when the ceramic substrate is peeled off from the ceramic substrate laminate, the ceramic substrate may be cracked or damaged, and the manufactured ceramic substrate may be defective. However, in the method for manufacturing the ceramic substrate of the present embodiment, the ceramic green sheet laminate 30P in which the sheet member 1 is interposed between the ceramic green sheets 20P is fired. Therefore, as described above, the firing step In P3, the ceramic particles of the sheet member 1 keep the laminated ceramic green sheets 20P apart from each other, and prevent the ceramic green sheets 20P from being fused to each other. Therefore, according to the method for manufacturing a ceramic substrate of the present embodiment, the ceramic substrate 20 can be easily peeled off from the ceramic substrate laminate 30, and the ceramic substrate 20 cracks when the ceramic substrate 20 is peeled off from the ceramic substrate laminate 30. It is suppressed from being damaged or damaged. Therefore, a good ceramic substrate 20 can be manufactured.

By the way, as described above, when the thermal decomposition temperature of the first binder resin contained in the ceramic green sheet and the thermal decomposition temperature of the second binder resin contained in the sheet member are substantially the same, the ceramic green sheet is used. When firing the ceramic green sheet laminate in which the sheet member is arranged between them, the first binder resin and the second binder resin can be softened at the same time. In this case, the shape of the main surface of the sheet member distorted by the softening of the second binder resin can be easily transferred to the main surface of the ceramic green sheet which is easily deformed by the softening of the first binder resin. Therefore, the shape of the main surface of the ceramic substrate obtained by firing the ceramic green sheet can be distorted.

On the other hand, the binder resin of the sheet member 1 of the present embodiment is formed of a second binder resin having a thermal decomposition temperature lower than the thermal decomposition temperature of the first binder resin contained in the ceramic green sheet 20P. Further, in the method for manufacturing a ceramic substrate of the present embodiment, the sheet member 1 having such a second binder resin is arranged between the ceramic green sheets 20P. Therefore, according to the method for manufacturing the sheet member 1 and the ceramic substrate of the present embodiment, when the ceramic green sheet laminate 30P is fired, the softening of the second binder resin starts before the softening of the first binder resin. That is, at this stage when the second binder resin begins to soften, the first binder resin does not soften as much as the second binder resin, so that the ceramic green sheet 20P is less likely to be deformed than the sheet member 1. Therefore, it is possible to prevent the shapes of the main surfaces 10 and 11 of the sheet member 1 distorted by the softening of the first binder resin from being transferred to the main surface of the ceramic green sheet 20P. Therefore, according to the method for manufacturing the sheet member 1 and the ceramic substrate of the present embodiment, the sintering is performed as compared with the case where the thermal decomposition temperature of the first binder resin and the thermal decomposition temperature of the second binder resin are substantially the same. The shape of the main surface of the ceramic substrate can be suppressed from being distorted, and a good ceramic substrate can be manufactured.

The difference between the thermal decomposition temperature of the first binder resin and the thermal decomposition temperature of the second binder resin is preferably 10 ° C. or higher and 100 ° C. or lower.

When the difference between the thermal decomposition temperature of the first binder resin and the thermal decomposition temperature of the second binder resin is 10 ° C. or more, the difference between the thermal decomposition temperature of the first binder resin and the thermal decomposition temperature of the second binder resin is 0. Since there is a difference between the thermal decomposition temperature of the first binder resin and the thermal decomposition temperature of the second binder resin as compared with the case where the temperature is larger than ° C and smaller than 10 ° C, the ceramic is formed at the stage when the sheet member starts to soften. Green sheets tend to be more resistant to deformation. Therefore, the transfer of the distorted shape of the main surface of the sheet member to the ceramic green sheet can be suppressed more effectively. On the other hand, when the difference between the thermal decomposition temperature of the first binder resin and the thermal decomposition temperature of the second binder resin is 100 ° C. or less, the difference between the thermal decomposition temperature of the first binder resin and the thermal decomposition temperature of the second binder resin is Compared with the case where the temperature is higher than 100 ° C., thermal decomposition and thermal shrinkage of the sheet member due to warm air of the coater used at the time of manufacturing the sheet member can be suppressed, and the manufactured sheet member can be made flatter. Therefore, by using such a sheet member having good flatness, a better ceramic substrate can be manufactured.

Further, the difference between the thermal decomposition temperature of the first binder resin and the thermal decomposition temperature of the second binder resin may be 25 ° C. or higher and 60 ° C. or lower.

In this case, as will be described later, it is possible to more effectively suppress the shape of the main surface of the ceramic substrate 20 from becoming distorted.

If the thermal decomposition temperature of the second binder resin is lower than the thermal decomposition temperature of the first binder resin, it is within the range of the difference between the thermal decomposition temperature of the second binder resin and the thermal decomposition temperature of the first binder resin. The lower limit may be less than 10 ° C. and the upper limit may be greater than 100 ° C.

Further, in the above embodiment, the example in which the sheet member 1 is arranged between all the ceramic green sheets 20P to be laminated has been described, but the sheet member 1 is arranged between at least one pair of adjacent ceramic green sheets 20P. If this is done, it is possible to prevent the main surface of the ceramic substrate 20 formed from the ceramic green sheet 20P on which the sheet member 1 is arranged from becoming distorted.

Next, specific examples of the present invention will be described together with comparative examples, but the present invention is not limited to these examples.

Before performing Examples 1, 2 and Comparative Examples described later, the thermal decomposition temperatures of the first binder resin and the second binder resin used in Examples 1, 2 and Comparative Examples were measured. ..

Specifically, acrylic resin A and polyvinyl butyral (PVB) resin were prepared as the first binder resin. Further, as the second binder resin, an acrylic resin B different from the acrylic resin A was prepared.

Next, the thermal decomposition temperatures of the acrylic resin A, the polyvinyl butyral (PVB) resin, and the acrylic resin B were measured by thermogravimetric analysis (TG). Specifically, the temperature of the sample was raised from room temperature to 600 ° C., and the weight of the sample at the start of measurement at room temperature was 100 wt%, and the temperature at which the weight of the sample became 90 wt% was measured. The temperature at which this weight became 90 wt% was defined as the thermal decomposition temperature. The result is shown in FIG.

As shown in FIG. 6, it was found that the thermal decomposition temperature at which the weight of the acrylic resin B was 90 wt% was 277.5 ° C. Further, it was found that the thermal decomposition temperature at which the weight of the acrylic resin A was 90 wt% was 307.5 ° C. Further, it was found that the thermal decomposition temperature at which the weight of the PVB-based resin was 90 wt% was 334.0 ° C. That is, it was found that the thermal decomposition temperature of the acrylic resin B, which is the second binder resin, is 30 ° C. lower than the thermal decomposition temperature of the acrylic resin A, which is the first binder resin. It was also found that the thermal decomposition temperature of the acrylic resin B, which is the second binder resin, is 56.5 ° C. lower than that of the PVB resin, which is the first binder resin.

(Example 1)
Next, a ceramic green sheet 20P containing the PVB-based resin was prepared as the first binder resin, and a sheet member 1 containing the acrylic resin B was prepared as the second binder resin.

Specifically, the ceramic green sheet 20P was produced as follows.

First, a slurry was prepared by mixing a predetermined amount of each of aluminum oxide, a sintering aid, the PVB-based resin as the first binder resin, a predetermined solvent, and a predetermined plasticizer. The blending amount of the PVB-based resin, which is the first binder resin, in the slurry was set to 6.1 wt%. Next, using this slurry, a plurality of ceramic green sheets 20P having a main surface size of 80 mm × 70 mm and a thickness of 0.34 mm were produced.

Further, the sheet member 1 was manufactured as follows.

First, a dispersion liquid containing aluminum oxide, the acrylic resin B as the second binder resin, carbon particles, and a dispersant was prepared. The blending amount of the acrylic resin B, which is the second binder resin, in the dispersion liquid was set to 30.0 wt%. Further, sorbitan sesquiolate was used as a dispersant, and the blending amount of this dispersant in the dispersion was set to 0.8 wt%. Next, using this dispersion, a plurality of sheet members 1 having a main surface size of 80 mm × 70 mm and a thickness of 0.07 mm were produced.

Next, based on the laminate forming step P2, nine sheet members 1 and ten ceramic green sheets 20P were alternately laminated one by one to form a ceramic green sheet laminate 30P. Then, the firing step P3 was performed. Specifically, the ceramic green sheet laminate 30P was fired at a temperature of 1560 ° C. for a predetermined time using an electric furnace. In this way, the ceramic substrate laminate 30 was produced. Then, the peeling step P4 was performed, and the ceramic substrates 20 were peeled off one by one from the ceramic substrate laminate 30.

The state of the main surface of the ceramic substrate 20 after the peeling step P4 was confirmed. Specifically, in the firing step P3, the state of the main surface of the ceramic substrate 20 in contact with any of the main surfaces 10 and 11 of the sheet member 1 was confirmed. This confirmation was performed as follows.

As described above, after the firing step P3, the ceramic particles derived from the sheet member 1 remain between the laminated ceramic substrates 20. Therefore, when a recess is formed on the main surface of the ceramic substrate 20 in the firing step P3, ceramic particles derived from the sheet member 1 can enter the recess. If the shape of the main surface of the ceramic substrate 20 is distorted and the shape of the recess is distorted, the ceramic particles derived from the sheet member 1 are fitted into the recess, and it may be difficult to remove the ceramic particles.

Therefore, the inventors have determined that when the main surface of the ceramic substrate 20 does not have a dent that is so distorted that the ceramic particles that have entered the dent cannot be removed, the main surface of the ceramic substrate is not roughened and the main surface of the ceramic substrate is main. The surface was evaluated as good.

On the other hand, the inventors evaluated that when the main surface of the ceramic substrate 20 had a dent that was so distorted that the ceramic particles that had entered the dent could not be removed, the main surface of the ceramic substrate was rough.

(Example 2)
Further, the ceramic substrate 20 was produced by making various conditions such as the blending amount, the firing temperature, and the firing time the same as in Example 1 except that the first binder resin of the ceramic green sheet was the acrylic resin A. The roughness of the main surface of the ceramic substrate 20 was evaluated according to the same criteria as in Example 1.

(Comparison example)
Further, except that the first binder resin of the ceramic green sheet is the same acrylic resin B as the second binder resin, various conditions such as the blending amount, the firing temperature, and the firing time are the same as in Example 1, and the ceramic is ceramic. A substrate 20 was produced, and the roughness of the main surface of the ceramic substrate 20 was evaluated according to the same criteria as in Example 1. That is, in this comparative example, the thermal decomposition temperatures of the first binder resin and the second binder resin are the same.

The results of Example 1, Example 2, and Comparative Example are shown in Table 1.

As shown in Table 1, in Example 1, the main surface of each ceramic substrate 20 obtained in the peeling step P4 does not have a dent that is so distorted that the ceramic particles that have entered the dent cannot be removed. confirmed. That is, it was confirmed that the main surface of the ceramic substrate was not rough and the main surface of the ceramic substrate was good.

Further, as shown in Table 1, also in Example 2, there is no dent that is so distorted that the ceramic particles that have entered the dent cannot be removed from the main surface of each ceramic substrate 20 obtained in the peeling step P4. It was confirmed that. That is, it was confirmed that the main surface of the ceramic substrate was not rough and the main surface of the ceramic substrate was good.

On the other hand, as shown in Table 1, in Comparative Example 1, the main surface of each ceramic substrate 20 obtained in the peeling step P4 has a dent that is so distorted that the ceramic particles that have entered the dent cannot be removed. Was confirmed. That is, it was confirmed that the main surface of the ceramic substrate was rough.

As described above, the ceramic green sheet laminate 30P is formed by using the sheet member 1 containing the PVB-based resin whose thermal decomposition temperature is 56.5 ° C. lower than that of the first binder resin as the second binder resin, and this ceramic. It was found that when the green sheet laminate 30P is fired, the ceramic substrate 20 having a better main surface can be produced as compared with the case where the first binder resin and the second binder resin have the same thermal decomposition temperature. ..

Further, the ceramic green sheet laminate 30P is formed by using the sheet member 1 containing the acrylic resin A whose thermal decomposition temperature is 30 ° C. lower than that of the first binder resin as the second binder resin, and the ceramic green sheet laminate 30P is formed. It was found that when 30P is fired, the ceramic substrate 20 having a better main surface can be produced as compared with the case where the first binder resin and the second binder resin have the same thermal decomposition temperature.

That is, when the thermal decomposition temperature of the second binder resin is lower than the thermal decomposition temperature of the first binder resin, the ceramic substrate 20 having a good main surface can be manufactured, and in particular, the thermal decomposition temperature of the second binder resin is the second. It was confirmed that the ceramic substrate 20 having a good main surface can be produced more effectively when the temperature is lower than the thermal decomposition temperature of the binder resin in the range of 25 ° C. or higher and 60 ° C. or lower.

According to the present invention, a method for manufacturing a sheet member and a ceramic substrate that can manufacture a good ceramic substrate is provided, and is used in the field of manufacturing a ceramic substrate for mounting electronic components and other ceramic substrates. Can be done.

1 ... Sheet members 10, 11 ... Main surface 20P ... Ceramic green sheet 20 ... Ceramic substrate 30P ... Ceramic green sheet laminate 30 ... Ceramic substrate laminate

Claims (6)

A sheet member arranged between ceramic green sheets containing a first binder resin when a ceramic substrate is manufactured.
It is provided with ceramic particles, carbon particles, and a second binder resin different from the first binder resin.
A sheet member characterized in that the thermal decomposition temperature of the second binder resin is lower than the thermal decomposition temperature of the first binder resin. The sheet member according to claim 1, wherein the difference between the thermal decomposition temperature of the first binder resin and the thermal decomposition temperature of the second binder resin is 10 ° C. or higher and 100 ° C. or lower. The sheet member according to claim 2, wherein the difference between the thermal decomposition temperature of the first binder resin and the thermal decomposition temperature of the second binder resin is 25 ° C. or higher and 60 ° C. or lower. It has a plurality of ceramic green sheets containing the first binder resin, ceramic particles, carbon particles, and a second binder resin different from the first binder resin, and the thermal decomposition temperature of the second binder resin is determined. A preparatory step of preparing at least one sheet member having a temperature lower than the thermal decomposition temperature of the first binder resin, and
A laminate forming step of arranging the sheet members between the ceramic green sheets to be laminated to form a ceramic green sheet laminate, and
A firing step of firing the ceramic green sheet laminate to form a ceramic substrate laminate,
The peeling step of peeling the ceramic substrate from the ceramic substrate laminate and
A method for manufacturing a ceramic substrate, which comprises. The method for manufacturing a ceramic substrate according to claim 4, wherein the difference between the thermal decomposition temperature of the first binder resin and the thermal decomposition temperature of the second binder resin is 10 ° C. or higher and 100 ° C. or lower. The method for manufacturing a ceramic substrate according to claim 5, wherein the difference between the thermal decomposition temperature of the first binder resin and the thermal decomposition temperature of the second binder resin is 25 ° C. or higher and 60 ° C. or lower.

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