JP2010042964A - Ceramic raw material powder and its manufacturing method, ceramic green sheet and its manufacturing method, and manufacturing method of ceramic substrate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a ceramic raw material powder and its manufacturing method, a ceramic green sheet and its manufacturing method, and a manufacturing method of a ceramic substrate, which can easily discriminate between a ceramic green sheet and a conductor pattern by image recognition. <P>SOLUTION: The ceramic raw material powder is a mixture of a calcined powder fabricated by calcining a first raw material powder in an oxidative atmosphere and an uncalcined second raw material powder. The first raw material is composed of a component which is substantially not discolored even if calcined in an oxidative atmosphere, and the second raw material powder contains a component which is substantially discolored if calcined in an oxidative atmosphere. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a ceramic raw material powder and a manufacturing method thereof, a ceramic green sheet and a manufacturing method thereof, and a manufacturing method of a ceramic substrate.

  Conventionally, for example, a ceramic multilayer substrate obtained by laminating a plurality of ceramic green sheets, forming a circuit composed of a conductor pattern layer between the ceramic green sheets, and then firing the circuit is known.

A dielectric ceramic composition suitable for producing such a ceramic multilayer substrate is disclosed in, for example, Japanese Patent Application Laid-Open No. 2002-173362 (hereinafter referred to as Patent Document 1). In this dielectric ceramic composition, the Si component is converted to SiO ₂ and 35.0 to 65.0% by weight, the Ba component is converted to BaCO ₃ and 20.0 to 50.0% by weight, and the Mn component is converted to MnCO. ₃ in terms of 5.0 to 35.0 wt%, 3.0 to 10.0 wt% in terms of Al component to _Al 2 _{O 3,} in terms of Cr component _Cr 2 _{O 3} 0.3 ˜3.0 wt%, and Ca component is contained 0.3 to 3.0 wt% in terms of CaCO ₃ .

As a method for producing a ceramic multilayer substrate described in Patent Document 1, first, a raw material powder obtained by mixing all the components constituting the above dielectric ceramic composition is temporarily prepared at 850 to 950 ° C., for example. After baking and pulverization, an organic binder is added and kneaded, and a ceramic green sheet is produced by forming into a sheet shape by a doctor blade method. A conductor pattern layer is formed by printing a copper paste on the ceramic green sheet. Then, a plurality of ceramic green sheets are laminated, and a circuit composed of a conductor pattern layer is formed between the ceramic green sheets.
JP 2002-173362 A

  However, the conventional method for manufacturing a ceramic multilayer substrate described in Patent Document 1 has the following problems.

  Since the raw material powder contains a Mn component, the calcined powder has a blackish brown color. Moreover, the ceramic green sheet shape | molded using said calcining powder also exhibits black brown. The conductor pattern layer formed on the ceramic green sheet has a red color because it contains copper. For this reason, it becomes difficult to distinguish between the ceramic green sheet exhibiting black-brown color and the conductive pattern layer exhibiting red color.

  Thus, when a conductor pattern layer is formed at a predetermined position of the ceramic green sheet by printing using a screen mask, when a via hole is formed using a laser or the like so as to be connected to the conductor pattern layer, When forming a via-hole conductor layer by filling a conductor component, the alignment required when aligning and laminating a plurality of ceramic green sheets to form a circuit composed of a conductor pattern layer between the ceramic green sheets is performed. There is a problem that it cannot be performed by recognizing an image of a ceramic green sheet or a conductor pattern layer.

  Accordingly, an object of the present invention is to make it possible to easily identify a ceramic green sheet and a conductor pattern layer by image recognition, a ceramic raw material powder and a method for manufacturing the same, a ceramic green sheet and a method for manufacturing the same, and manufacturing a ceramic substrate Is to provide a method.

  The ceramic raw material powder according to the present invention is a ceramic raw material powder containing a mixture of a heat treated powder produced by heat-treating the first raw material powder in an oxidizing atmosphere and a second raw material powder that has not been heat-treated. The first raw material powder is composed of components that are not substantially discolored even when heat-treated in an oxidizing atmosphere, and the second raw material powder is composed of components that are substantially discolored when heat-treated in an oxidizing atmosphere. Including.

  Since the ceramic raw material powder thus configured is not substantially discolored by the heat treatment, the ceramic green sheet is not substantially discolored even if the ceramic green sheet is formed using this ceramic raw material powder. For this reason, even if a colored conductor pattern layer is formed on the ceramic green sheet, the ceramic green sheet and the conductor pattern layer can be easily identified by image recognition.

  In the ceramic raw material powder of the present invention, the second raw material powder preferably contains a transition metal that exhibits a different color as the valence changes.

  In this case, the first raw material powder is composed of components that do not include a transition metal that exhibits a different color when the valence changes when heat-treated in an oxidizing atmosphere, and the valence changes when heat-treated in an oxidizing atmosphere. By configuring the second raw material powder with a component containing a transition metal that exhibits a different color depending on the ceramic raw material powder that makes it possible to easily identify the ceramic green sheet and the conductor pattern layer by image recognition be able to.

  In the ceramic raw material powder of the present invention, the transition metal preferably contains at least one metal selected from the group consisting of manganese, iron, copper and titanium.

Further, in the ceramic raw material powder of the present invention, the first material powder, in terms of Si component in SiO ₂ 47.0-67.0 wt%, in terms of Ba component in BaO 21.0 to 41. 0 wt%, and the Al component with _Al containing 10.0 to 18.0 wt% in terms of 2 _{O 3,} respectively in terms of the above Si component in SiO 2, BaO and _Al 2 _{O 3,} Ba component and When the total of the Al components is 100 parts by weight, the Ce component is converted to CeO ₂ with respect to 100 parts by weight, and 1.0 to 5.0 parts by weight is included. The second raw material powder is SiO ₂ , When the total of the Si component, Ba component, Al component and Ce component converted to BaO, Al ₂ O ₃ and CeO ₂ is 100 parts by weight, the Mn component is converted to MnO with respect to 100 parts by weight. do it It is preferable that the ceramic raw material powder contains 2.5 to 5.5 parts by weight and does not substantially contain Cr.

  By using the ceramic raw material powder configured in this way, it is possible to easily identify the ceramic green sheet and the conductor pattern layer by image recognition, and to improve the bending strength of the sintered body, Cr By using a ceramic raw material powder that does not substantially contain any of the above, it is possible to suppress a decrease in the Q value in the microwave band, for example, to obtain a Qxf value of 1000 or more at 3 GHz.

  The ceramic green sheet according to the present invention includes the above-mentioned ceramic raw material powder.

  Even if a colored conductor pattern layer is formed on the ceramic green sheet, the ceramic green sheet and the conductor pattern layer can be easily identified by image recognition.

  A method for producing a ceramic raw material powder according to the present invention includes a step of heat-treating a first raw material powder in an oxidizing atmosphere to produce a heat-treated powder, and the heat-treated powder and a second raw material powder that has not been heat-treated. The first raw material powder is composed of components that do not substantially discolor even when heat-treated in an oxidizing atmosphere, and the second raw material powder is in an oxidizing atmosphere. Contains a component that changes color substantially upon heat treatment.

  Since the ceramic raw material powder obtained by this manufacturing method is not substantially discolored by heat treatment, the ceramic green sheet is not substantially discolored even when the ceramic green sheet is formed using this ceramic raw material powder. For this reason, even if a colored conductor pattern layer is formed on the ceramic green sheet, the ceramic green sheet and the conductor pattern layer can be easily identified by image recognition.

  In the method for producing a ceramic raw material powder according to the present invention, the second raw material powder preferably contains a transition metal that exhibits a different color as the valence changes.

  In this case, the first raw material powder is composed of components that do not include a transition metal that exhibits a different color when the valence changes when heat-treated in an oxidizing atmosphere, and the valence changes when heat-treated in an oxidizing atmosphere. By configuring the second raw material powder with a component containing a transition metal that exhibits a different color depending on the ceramic raw material powder that makes it possible to easily identify the ceramic green sheet and the conductor pattern layer by image recognition be able to.

  In the method for producing a ceramic raw material powder according to the present invention, the transition metal preferably contains at least one metal selected from the group consisting of manganese, iron, copper and titanium.

Furthermore, in the method for producing a ceramic raw material powder according to the present invention, the first raw material powder has a Si component converted to SiO ₂ of 47.0 to 67.0% by weight, and a Ba component converted to BaO of 21.0. ～41.0 wt%, and, together with the Al component comprises 10.0 to 18.0 wt% in terms of _Al 2 _{O 3,} the above Si component in terms respectively SiO 2, BaO and _Al 2 _{O 3,} When the total of the Ba component and Al component is 100 parts by weight, the Ce component is converted to CeO ₂ with respect to 100 parts by weight, and 1.0 to 5.0 parts by weight, and the second raw material powder is: When the total of the Si component, Ba component, Al component and Ce component converted to SiO ₂ , BaO, Al ₂ O ₃ and CeO ₂ is 100 parts by weight, the Mn component is added to 100 parts by weight. MnO It is preferable that the ceramic raw material powder contains 2.5 to 5.5 parts by weight in terms of and substantially does not contain Cr.

  By producing the ceramic raw material powder configured in this way, it is possible to easily identify the ceramic green sheet and the conductor pattern layer by image recognition, and to improve the bending strength of the sintered body, By using a ceramic raw material powder that does not substantially contain Cr, it is possible to suppress a decrease in the Q value in the microwave band and obtain, for example, a Qxf value of 1000 or more at 3 GHz.

  The method for producing a ceramic green sheet according to the present invention includes a step of producing a ceramic green sheet containing the ceramic raw material powder obtained by the above-described production method.

  Even if a colored conductor pattern layer is formed on the ceramic green sheet obtained by this manufacturing method, the ceramic green sheet and the conductor pattern layer can be easily identified by image recognition.

  A method for manufacturing a ceramic substrate according to one aspect of the present invention includes a step of forming a conductor layer on a ceramic green sheet obtained by the above-described manufacturing method, and a step of firing the ceramic green sheet.

  In this method of manufacturing a ceramic substrate, even if a colored conductor layer is formed on the ceramic green sheet, the ceramic green sheet and the conductor pattern layer can be easily identified by image recognition.

  A method of manufacturing a ceramic substrate according to another aspect of the present invention includes a step of forming a conductor layer on a ceramic green sheet obtained by the above-described manufacturing method, and a laminate by stacking a plurality of ceramic green sheets. A step of forming, and a step of firing the laminate.

  In this method of manufacturing a ceramic substrate, even if a colored conductor layer is formed on the ceramic green sheet, the ceramic green sheet and the conductor pattern layer can be easily identified by image recognition.

  In the method for manufacturing a ceramic substrate according to one aspect or another aspect of the present invention, the conductor layer preferably contains copper as a main component.

  In this case, in the method for manufacturing a ceramic substrate, even if a conductor layer made of copper exhibiting red color is formed on the ceramic green sheet, the ceramic green sheet and the conductor pattern layer can be easily identified by image recognition.

  As described above, according to the present invention, it is possible to obtain a ceramic raw material powder and a ceramic green sheet that enable easy recognition of the ceramic green sheet and the conductor pattern layer by image recognition. Even if a colored conductor layer is formed on the ceramic green sheet, the ceramic green sheet and the conductor pattern layer can be easily identified by image recognition.

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

  FIG. 1 is a cross-sectional view schematically showing a multilayer ceramic substrate 1 as an example of a ceramic substrate manufactured using a ceramic raw material powder according to the present invention.

  As shown in FIG. 1, the multilayer ceramic substrate 1 includes a laminate 3. The laminate 3 is composed of a plurality of laminated ceramic layers 2. Various conductor pattern layers are provided on the outer surface and inside of the laminate 3 in association with predetermined ceramic layers 2.

  The conductor pattern layer includes several outer conductor pattern layers 4 and 5 formed on the end face in the stacking direction of the multilayer body 3, and some of the conductor pattern layers formed along a specific interface between the plurality of ceramic layers 2. It is composed of an internal conductor pattern layer 6 and several via hole conductor layers 7 formed so as to penetrate a predetermined ceramic layer 2.

  The external conductor pattern layer 4 formed on the upper surface side of the multilayer body 3 is used to connect to the electronic components 8 and 9 to be mounted on the outer surface of the multilayer body 3. FIG. 1 shows an electronic component 8 having a bump electrode 10 such as a semiconductor device, for example, an electronic component 9 having a planar terminal electrode 11 such as a chip capacitor.

  The external conductor pattern layer 5 formed on the lower surface side of the multilayer body 3 is used for connection to a mother board (not shown) on which the multilayer ceramic substrate 1 is mounted.

  The laminate 3 configured as described above is obtained by firing a raw laminate. The raw laminate includes a plurality of laminated ceramic green sheets that become the ceramic layer 2 by firing, and a conductive paste layer that becomes the internal conductor pattern layer 6 and the via-hole conductor layer 7 by firing. In some cases, a conductive paste layer to be the outer conductor pattern layers 4 and 5 is further provided.

  A green laminate is typically obtained by laminating a plurality of ceramic green sheets obtained by forming a ceramic slurry, and the conductor pattern layer, particularly the inner conductor pattern layer, is a ceramic before lamination. Provided on the green sheet.

  As will be described later, the ceramic slurry is composed of a ceramic raw material powder having a composition characteristic of the present invention, an organic binder such as polyvinyl butyral, an organic solvent such as toluene and isopropyl alcohol, and di-n-butyl phthalate. Such a plasticizer and, if necessary, other additives such as a dispersant can be added to obtain a slurry.

Molding for obtaining a ceramic green sheet using a ceramic slurry is performed, for example, by forming a ceramic slurry into a sheet by applying a doctor blade method on a carrier film made of an organic resin such as polyethylene terephthalate. .

  In order to form the conductor pattern layer on the ceramic green sheet, for example, a conductive paste containing copper as a main component of the conductive component is used, and a through hole for the via-hole conductor layer 7 is provided in the ceramic green sheet. The conductive paste layer for the inner conductor pattern layer 6 and the conductive paste layers for the outer conductor pattern layers 4 and 5 as necessary are formed by, for example, a screen printing method. Is done.

Such ceramic green sheets are laminated in a predetermined order and pressed in the lamination direction with a pressure of, for example, 1000 kgf / cm ² to obtain a raw laminate.

  Although not shown, this raw laminate may be provided with a cavity for accommodating other electronic components, and a joint portion for fixing a cover that covers the electronic components 8 and 9 and the like.

  The raw laminate is at or above the temperature at which the ceramic composition contained in the ceramic green layer can be sintered, for example 900 ° C. or more, and below the melting point of the metal contained in the conductor pattern layer, for example, copper, 1030 ° C. Baking is performed in the following temperature range.

  Further, when the metal contained in the conductor pattern layer is copper, the firing is performed in a non-oxidizing atmosphere such as a nitrogen atmosphere, and the binder removal is completed at a temperature of 900 ° C. or lower. The partial pressure is lowered so that the copper is not substantially oxidized upon completion of firing.

  As described above, the laminate 3 shown in FIG. 1 is obtained by firing the raw laminate.

  Thereafter, the outer conductor pattern layers 4 and 5 are formed as necessary, and the electronic components 8 and 9 are mounted. As described above, the multilayer ceramic substrate 1 shown in FIG. 1 is completed.

  The present invention can be applied not only to a multilayer ceramic substrate including a multilayer body having the above-described multilayer structure but also to a single-layer ceramic substrate including a single ceramic layer.

  The ceramic raw material powder of the present invention is used for producing the above-described ceramic green sheet and ceramic substrate.

  As one embodiment of the ceramic raw material powder according to the present invention, a heat-treated powder produced by heat-treating the first raw material powder in an oxidizing atmosphere and a second raw-material powder that has not been heat-treated A ceramic raw material powder containing a mixture, wherein the first raw material powder is composed of components that do not substantially discolor even when heat-treated in an oxidizing atmosphere, and the second raw material powder is heat-treated in an oxidizing atmosphere. Contains a component that substantially changes color.

In this case, BaCO ₃ , SiO ₂ , Al ₂ O _3, or the like can be used as a component that is not substantially discolored even when heat-treated in an oxidizing atmosphere, and substantially when heat-treated in an oxidizing atmosphere. As the component that changes color, for example, MnCO ₃ can be used. When MnCO ₃ is heat-treated in an oxidizing atmosphere, for example, in air, the following reaction occurs.

2MnCO ₃ + O ₂ → 2MnO ₂ + 2CO ₂
Here, MnCO ₃ exhibits a brown color, and MnO ₂ exhibits a black or dark brown color. An oxidation reaction of Mn occurs, and MnCO ₃ (Mn ²⁺ : valence is divalent) changes to MnO ₂ (Mn ⁴⁺ : valence is tetravalent).

In contrast, when MnCO ₃ is heat-treated in a non-oxidizing atmosphere, for example, in nitrogen gas, the following reaction occurs.

MnCO ₃ → MnO + CO ₂
Here, MnCO ₃ is brown and MnO is almost colorless.

In addition, when the ceramic raw material powder containing MnCO ₃ is fired, finally, the fired product contains Mn ₂ O ₃ , Mn ₃ O ₄ , MnO, and the like, and becomes gray.

  Since the ceramic raw material powder thus configured is not substantially discolored by the heat treatment, the ceramic green sheet is substantially discolored even if the ceramic green sheet is formed using the ceramic raw material powder as described above. Not. For this reason, even if a red conductive paste layer containing copper as the main component of the conductive component is formed as a colored conductive pattern layer on the ceramic green sheet, the green sheet and the conductive pattern layer can be easily identified by image recognition. It becomes possible to do.

  In the ceramic raw material powder of the present invention, the second raw material powder preferably contains a transition metal that exhibits a different color as the valence changes. For example, as a transition metal, iron, copper, titanium, etc. can be mentioned besides manganese. The transition metal contained in the second raw material powder may be at least one metal selected from the group consisting of manganese, iron, copper, and titanium.

In this case, the first raw material powder is composed of a component that does not include a transition metal that exhibits a different color due to a change in valence when heat-treated in an oxidizing atmosphere, such as BaCO ₃ , SiO ₂ , Al ₂ O _{3, and the} like. By forming the second raw material powder with a component containing a transition metal that exhibits a different color when the valence changes when heat-treated in an oxidizing atmosphere, for example, MnCO ₃ , a green sheet and a conductor pattern layer are formed by image recognition. Therefore, it is possible to easily configure the ceramic raw material powder that makes it possible to easily identify the material.

Further, in the ceramic raw material powder of the present invention, the first material powder, in terms of Si component in SiO ₂ 47.0-67.0 wt%, in terms of Ba component in BaO 21.0 to 41. 0 wt%, and the Al component with _Al containing 10.0 to 18.0 wt% in terms of 2 _{O 3,} respectively in terms of the above Si component in SiO 2, BaO and _Al 2 _{O 3,} Ba component and When the total of the Al components is 100 parts by weight, the Ce component is converted to CeO ₂ with respect to 100 parts by weight, and 1.0 to 5.0 parts by weight is included. The second raw material powder is SiO ₂ , When the total of the Si component, Ba component, Al component and Ce component converted to BaO, Al ₂ O ₃ and CeO ₂ is 100 parts by weight, the Mn component is converted to MnO with respect to 100 parts by weight. do it It is preferable that the ceramic raw material powder contains 2.5 to 5.5 parts by weight and does not substantially contain Cr.

  By using the ceramic raw material powder configured in this way, it becomes possible to easily identify the green sheet and the conductor pattern layer by image recognition, and it is possible to improve the bending strength of the sintered body, Cr By using the ceramic raw material powder which is not substantially contained, a decrease in the Q value in the microwave band can be suppressed, and for example, a Qxf value of 1000 or more can be obtained at 3 GHz.

  The ceramic green sheet according to the present invention includes the above-mentioned ceramic raw material powder.

  Even if a colored conductor pattern layer is formed on the ceramic green sheet, the ceramic green sheet and the conductor pattern layer can be easily identified by image recognition.

  FIG. 2 is a flowchart showing a method of manufacturing a ceramic green sheet using the ceramic raw material powder of the present invention and a method of manufacturing a ceramic substrate in the order of steps.

As shown in FIG. 2, in step S1, a mixed powder containing, for example, BaCO ₃ , SiO ₂ , Al ₂ O _{3 and the} like is prepared as the first raw material powder. Thereafter, in step S2, the first raw material powder is calcined as an example of heat treatment in an oxidizing atmosphere to obtain a calcined powder.

On the other hand, in step S3, a powder containing MnCO ₃ or the like is prepared as the second raw material powder.

  In step S4, the first and second raw material powders are mixed to produce a mixed powder. Thereafter, in step S5, a ceramic slurry is prepared by adding an organic binder, an organic solvent, a dispersant, a plasticizer, and the like to the obtained mixed powder by the method described above.

  In step S6, a ceramic green sheet is produced by forming a ceramic slurry by the method described above.

  In step S7, the conductive paste layer that becomes the outer conductor pattern layers 4 and 5 and the inner conductor pattern layer 6 shown in FIG. 1 is formed as a conductor pattern layer at a predetermined position of the ceramic green sheet by the method described above. It is formed by printing using a screen mask. Further, via holes are formed in the ceramic green sheet using a laser or the like so as to be connected to the conductor pattern layer. Further, the via hole is filled with a conductor component to form a conductive paste layer that becomes the via hole conductor layer 7 shown in FIG.

  Furthermore, in step S8, the plurality of ceramic green sheets on which the conductive paste layer is formed are stacked and pressure-bonded by the method described above. At this time, a plurality of ceramic green sheets are aligned and laminated to form a circuit composed of a conductive pattern layer between the ceramic green sheets.

  In the embodiment of the present invention, the alignment required in the above steps S7 and S8 can be performed by image recognition of the ceramic green sheet or the conductor pattern layer.

  In step S9, the multilayered ceramic substrate 1 shown in FIG. 1 can be obtained by firing the laminate of ceramic green sheets in a non-oxidizing atmosphere by the method described above.

  An embodiment of the present invention will be described below.

  The ceramic raw material powder of the example of the present invention and the ceramic raw material powder of the comparative example were produced as follows.

First, a calcined powder included in the ceramic raw material powder of the example was prepared. The calcined powder was produced by calcining the first raw material powder in the air as an example of an oxidizing atmosphere. As the first raw material powder, the composition of the calcined powder obtained after calcining is BaO: 31.0 wt%, SiO ₂ : 57.0 wt%, Al ₂ O ₃ : 12.0 wt% A powder obtained by weighing each powder of BaCO ₃ , SiO ₂ , and Al ₂ O ₃ having a particle size of 2.0 μm or less and wet-mixing them was used. In this case, the BaCO ₃ , SiO ₂ , and Al ₂ O ₃ powders are not substantially discolored even if calcined in the atmosphere. These mixed powders were dried and then calcined in the air at a temperature of 800 ° C. for 2 hours to obtain calcined powders of Examples.

The ceramic raw material powder of Example was produced by mixing the second raw material powder with the calcined powder. As the second raw material powder, MnCO ₃ powder is used, and the composition ratio of MnO obtained after firing is MnO: 5.0% by weight with respect to the total of 100% by weight of BaCO ₃ , SiO ₂ , and Al ₂ O _3. MnCO ₃ powder was added to the calcined powder so as to be. The results of observing the color of the ceramic raw material powders of the obtained examples are shown in Table 1 below.

Meanwhile, a calcined powder was produced as a ceramic raw material powder of a comparative example. The calcined powder was produced by calcining raw material powder in the air as an example of an oxidizing atmosphere. As the raw material powder, the composition ratio of BaCO ₃ , SiO ₂ , and Al ₂ O ₃ obtained after calcination is BaO: 31.0% by weight, SiO ₂ : 57.0% by weight, Al ₂ O ₃ : 12.0% by weight The particle size is 2.0 μm or less so that the composition ratio of MnO obtained after calcination is MnO: 5.0% by weight with respect to 100% by weight of BaCO ₃ , SiO ₂ , and Al ₂ O ₃ in total. Each powder of BaCO ₃ , SiO ₂ , Al ₂ O ₃ , and MnCO ₃ was weighed and wet-mixed. In this case, the BaCO ₃ , SiO ₂ , and Al ₂ O ₃ powders are substantially discolored even when calcined in the air, but MnCO ₃ is substantially submerged when calcined in the air. It will be discolored. These mixed powders were dried and then calcined in the air at a temperature of 800 ° C. for 2 hours to obtain a ceramic raw material powder of a comparative example. The results of observing the color of the obtained ceramic raw material powder of Comparative Example are shown in Table 1 below.

  A ceramic slurry was prepared by adding a predetermined amount of a predetermined organic binder, an organic solvent, a dispersant, and a plasticizer to each of the ceramic raw material powders of Examples and Comparative Examples obtained as described above and mixing them. The obtained ceramic slurry was subjected to defoaming treatment, and then the ceramic slurry was formed into a sheet shape by a doctor blade method and dried to prepare a ceramic green sheet having a thickness of 80 μm. The results of observing the colors of the obtained ceramic green sheets of Examples and Comparative Examples are shown in Table 1 below.

  On the surfaces of the obtained ceramic green sheets of Examples and Comparative Examples, a copper paste for forming a surface layer electrode was printed so as to have a size of 1.0 mm × 1.0 mm. The copper paste was produced by adding and kneading ethyl cellulose resin and tervineol to pure copper having an average particle size of 1.2 μm.

  It was investigated whether it was possible to recognize an image of the copper paste layer as the conductor layer printed on the surface of the ceramic green sheets of the example and the comparative example. Specifically, as an image recognition device, an image recognition device capable of recognizing a copper paste layer having a size of 1.0 mm × 1.0 mm can be recognized using an image recognition device of a screen printer MT-320 manufactured by Micro Tech Co., Ltd. Judged whether or not. The results are shown in Table 1 below.

In addition, after cutting the ceramic green sheets of the examples and comparative examples obtained above to a predetermined size, a plurality of them are laminated and thermocompression bonded under conditions of a temperature of 60 to 80 ° C. and a pressure of 1000 to 1500 kg / cm ^2. As a result, a raw ceramic green sheet laminate having a thickness of 1.2 mm, a width of 6.0 mm, and a length of 41.7 mm was obtained.

  By firing the obtained ceramic green sheet laminates of Examples and Comparative Examples in a non-oxidizing mixed gas atmosphere of nitrogen gas-hydrogen gas-steam at a maximum temperature of 990 ° C. and a holding time of 120 minutes. A ceramic multilayer substrate was produced as an example of the ceramic substrate.

  The bending strength and relative dielectric constant of the obtained multilayer ceramic substrates of Examples and Comparative Examples were measured by the following methods.

(Folding strength)
A sample having a thickness of 1.0 mm × width 5.0 mm × length 35.0 mm was prepared from the multilayer ceramic substrate, and the bending strength was measured by a three-point bending test method. The measurement conditions were span: 30 mm and head speed: 2 mm / min. The average value of the measured values of 20 samples is shown in Table 1 below.

(Relative permittivity)
With respect to the obtained multilayer ceramic substrate, the relative dielectric constant at a frequency of 3 GHz was measured by a perturbation method. The measured values are shown in Table 1 below.

  From Table 1, it can be seen that the ceramic raw material powder and the ceramic green sheet of the example exhibit white color, whereas the ceramic raw material powder and the ceramic green sheet of the comparative example exhibit blackish brown color. In addition, it was possible to recognize the image of the conductor layer made of the red copper paste layer printed on the ceramic green sheet of the example, but it was not possible to recognize the image of the conductor layer of the comparative example. Recognize. In the ceramic substrate of the example, as an example of a component that changes color when calcined in the atmosphere, the ceramic raw material powder mixed with the calcined powder without calcining in advance was fired, but Mn was calcined in advance. Thus, it can be seen that the same bending strength and relative dielectric constant as in the comparative example in which the ceramic raw material powder contained in the calcined powder was fired could be obtained.

  It should be considered that the embodiments and examples disclosed herein are illustrative and non-restrictive in every respect. The scope of the present invention is shown not by the above embodiments or examples but by the scope of claims, and is intended to include all modifications and variations within the meaning and scope equivalent to the scope of claims. .

It is sectional drawing which shows typically the multilayer ceramic substrate as an example of the ceramic substrate manufactured using the ceramic raw material powder according to this invention. It is a flowchart which shows the method of manufacturing a ceramic green sheet using the ceramic raw material powder of this invention, and also the method of manufacturing a ceramic substrate in order of a process.

Explanation of symbols

  1: multilayer ceramic substrate, 2: ceramic layer, 3: laminate, 4, 5: outer conductor pattern layer, 6: inner conductor pattern layer, 7: via hole conductor layer.

Claims (13)

A ceramic raw material powder comprising a mixture of a heat treated powder produced by heat treating the first raw material powder in an oxidizing atmosphere and a second raw material powder that has not been heat treated,
The first raw material powder includes a component that does not substantially change color even when heat-treated in an oxidizing atmosphere, and the second raw material powder includes a component that substantially changes color when heat-treated in an oxidizing atmosphere. Ceramic raw material powder.   2. The ceramic raw material powder according to claim 1, wherein the second raw material powder includes a transition metal that exhibits a different color as the valence changes. 3.   The ceramic raw material powder according to claim 2, wherein the transition metal contains at least one metal selected from the group consisting of manganese, iron, copper, and titanium. Wherein the first raw material powder is 47.0 to 67.0 wt% in terms of Si component in SiO _2, 21.0-41.0 wt% in terms of Ba component in BaO, and, the Al component with Al comprising from 10.0 to 18.0 wt% in terms of ₂ O _3, SiO 2, BaO and _Al the Si component in terms respectively 2 _{O 3,} the Ba component and the total 100 parts by weight of the Al component In the case of 100 parts by weight, the Ce component is converted to CeO ₂ and contains 1.0 to 5.0 parts by weight,
When the second raw material powder has a total of 100 parts by weight of the Si component, Ba component, Al component and Ce component converted to SiO ₂ , BaO, Al ₂ O ₃ and CeO ₂ , Containing 2.5 to 5.5 parts by weight of Mn component in terms of MnO with respect to 100 parts by weight; and
The ceramic raw material powder according to any one of claims 1 to 3, wherein the ceramic raw material powder does not substantially contain Cr.   The ceramic green sheet containing the ceramic raw material powder of any one of Claim 1- Claim 4. Producing a heat-treated powder by heat-treating the first raw material powder in an oxidizing atmosphere;
Producing a mixed powder containing a mixture of the heat-treated powder and the second raw material powder that has not been heat-treated,
The first raw material powder includes a component that does not substantially change color even when heat-treated in an oxidizing atmosphere, and the second raw material powder includes a component that substantially changes color when heat-treated in an oxidizing atmosphere. Manufacturing method of ceramic raw material powder.   The said 2nd raw material powder is a manufacturing method of the ceramic raw material powder of Claim 6 containing the transition metal which exhibits a different color by a valence changing.   The said transition metal is a manufacturing method of the ceramic raw material powder of Claim 7 containing the at least 1 sort (s) of metal chosen from the group which consists of manganese, iron, copper, and titanium. Wherein the first raw material powder is 47.0 to 67.0 wt% in terms of Si component in SiO _2, 21.0-41.0 wt% in terms of Ba component in BaO, and, the Al component with Al comprising from 10.0 to 18.0 wt% in terms of ₂ O _3, SiO 2, BaO and _Al the Si component in terms respectively 2 _{O 3,} the Ba component and the total 100 parts by weight of the Al component In the case of 100 parts by weight, the Ce component is converted to CeO ₂ and contains 1.0 to 5.0 parts by weight,
When the second raw material powder has a total of 100 parts by weight of the Si component, Ba component, Al component and Ce component converted to SiO ₂ , BaO, Al ₂ O ₃ and CeO ₂ , respectively. Containing 2.5 to 5.5 parts by weight of Mn component in terms of MnO with respect to 100 parts by weight; and
The said ceramic raw material powder is a manufacturing method of the ceramic raw material powder of any one of Claim 6-8 which does not contain Cr substantially.   The manufacturing method of a ceramic green sheet provided with the process of producing the ceramic green sheet containing the ceramic raw material powder obtained by the manufacturing method of any one of Claim 6-9. Forming a conductor layer on the ceramic green sheet obtained by the manufacturing method according to claim 10;
And a step of firing the ceramic green sheet. Forming a conductor layer on the ceramic green sheet obtained by the manufacturing method according to claim 10;
Forming a laminate by laminating a plurality of the ceramic green sheets;
A method for producing a ceramic substrate, comprising the step of firing the laminate.   The method for manufacturing a ceramic substrate according to claim 11, wherein the conductor layer contains copper as a main component.

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