JP2006310478A - Ceramic multilayer substrate and manufacturing method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method for a ceramic multilayer substrate wherein multiple internal conductors different in thickness are provided, downsizing, especially, reduction in profile can be facilitated, delamination and the like are less prone to occur, and the degree of freedom can be enhanced in design. <P>SOLUTION: The manufacturing method for the ceramic multilayer substrate includes a step of preparing multiple ceramic green sheets; and printing internal conductor paste on the ceramic green sheets 13. Specifically, the manufacturing method includes a step of printing and drying a first internal conductor pattern 18 composed of first internal conductor paste; printing a second internal conductor pattern 21 in a region other than the region, where the first internal conductor pattern 18 is printed so that its thickness differs after sintering, and drying it; and thereafter, sintering a laminated body obtained by laminating the multiple ceramic green sheets to obtain a sintered body. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a ceramic multilayer substrate having a ceramic sintered body in which a plurality of types of internal conductors are provided, such as a ceramic multilayer substrate, and more specifically, a plurality of types of internal conductors having different thicknesses are provided. The present invention relates to a ceramic multilayer substrate and a manufacturing method thereof.

  Conventionally, various ceramic multilayer substrates in which a capacitor unit, an inductance unit, and the like are formed by a plurality of internal conductor patterns have been proposed. In manufacturing this type of ceramic multilayer substrate, first, an internal conductor paste for forming an internal conductor pattern is printed on the ceramic green sheet. A plurality of ceramic green sheets on which the internal conductor paste is printed are laminated to obtain a laminate. By firing the obtained laminate, a ceramic multilayer substrate is produced.

  By the way, in order to form a capacitor unit and an inductance unit by the internal conductor pattern, various internal conductor patterns such as a wiring pattern, a capacitance formation pattern, an inductor formation pattern, and a ground pattern are printed on the ceramic green sheet.

  Of the internal conductor patterns, it is desired that the inductance forming pattern be formed as thick as possible in order not to lower the Q in the finally obtained inductance unit. On the other hand, since the capacitance formation pattern and the ground pattern have a relatively large area, there is a problem that delamination is likely to occur after firing when the thickness of the internal conductor pattern is increased.

  When forming an internal conductor pattern such as a ceramic multilayer substrate, the internal conductor paste is formed by printing the ceramic green sheet by screen printing or the like. In this case, in order to increase productivity or facilitate manufacture, printing is performed once on the ceramic green sheet, that is, printing is performed for each layer unit. Therefore, it was impossible to form a thick inductance pattern and a thin ground pattern or capacitance forming pattern at the same height position of the obtained sintered body.

  Therefore, Patent Document 1 below discloses a ceramic multilayer substrate in which a thick inductance pattern and a thin capacitance forming pattern are formed at different height positions as shown in FIG. .

  As shown in FIG. 5, in the ceramic multilayer substrate 101, capacitor units C1, C2, C3 and a coil unit I1 are formed in a ceramic sintered body 102. In order to form the capacitor units C1 to C3, capacitance forming patterns 103 to 108 are formed, and in order to form the coil unit I, an inductance pattern 109 is formed. The inductance pattern 109 is formed at a height position different from that of the capacitance formation patterns 103 to 108.

That is, by arranging the inductance pattern 109, which is required to be thick, and the ground pattern and the capacitance forming patterns 103 to 108, which are preferably thin, at different height positions, the respective thicknesses are set to the optimum thickness. It is possible to do.
JP 9-36603 A

  In the ceramic multilayer substrate 101 described in Patent Document 1, the inductance pattern 109 that is desirably thick and the capacitance formation patterns 103 to 108 that are desirably thin are formed at different height positions. Therefore, during manufacturing, an inner conductor paste for an inductance pattern is printed on a certain ceramic green sheet, and an inner conductor paste for a capacitance forming pattern is printed on another ceramic green sheet, and these ceramic green sheets are laminated. It was.

  For this reason, since the inductance pattern 109 and the capacitance formation patterns 103 to 108 are formed at different height positions, the thickness of the ceramic multilayer substrate 101 must be increased, and downsizing, in particular, reduction in height can be promoted. It was difficult. In addition, since the inductance pattern and the capacitance formation pattern are formed at different height positions, the degree of freedom in circuit design in the ceramic multilayer substrate 101 tends to be low.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a ceramic multilayer substrate capable of eliminating the above-described drawbacks of the prior art, increasing the degree of freedom in circuit design, and reducing the size, in particular, reducing the height, and a method for manufacturing the same. There is to do.

  A first invention of the present application includes a step of preparing a ceramic green sheet, a step of printing an internal conductor paste on the ceramic green sheet, and a plurality of sheets including at least one ceramic green sheet printed with the internal conductor paste In the method for producing a ceramic multilayer substrate comprising the steps of laminating ceramic green sheets and obtaining a laminated body and firing the laminated body to obtain a sintered body, the internal conductor paste is placed on the ceramic green sheet. The printing process includes a stage for printing a first internal conductor paste on a ceramic green sheet, a stage for drying the first internal conductor paste, and a first stage after drying the first internal conductor paste. The thickness after sintering in a part of the area other than the area where the inner conductor paste is printed is the first inner Characterized in that it comprises a stage for printing the second internal conductor paste such that the different thicknesses are the body paste, and a stage of drying said second internal conductor paste.

  In a specific aspect of the manufacturing method according to the first invention, in addition to the ceramic green sheet on which the internal conductor paste is printed, at least one third internal conductor having a uniform thickness after firing is printed. One ceramic green sheet is laminated.

  In another specific aspect of the method for producing a ceramic multilayer substrate according to the present invention, a ground electrode and / or a capacitor electrode is formed by baking the first internal conductor paste, and by baking the second internal conductor paste. Line conductors forming an inductance pattern and the like are formed.

  In still another specific aspect of the ceramic multilayer substrate according to the present invention, the conductive powder content of the second internal conductor paste is increased compared to the conductive powder content of the first internal conductor paste.

  In still another specific aspect of the ceramic multilayer substrate according to the present invention, the conductive powder content in the second internal conductor paste is 10% by weight or more than the conductive powder content in the first internal conductor paste. It is high.

  In still another specific aspect of the method for producing a ceramic multilayer substrate according to the present invention, the first internal conductor paste contains ceramic powder.

  A second invention of the present application includes a step of preparing a ceramic green sheet, a step of printing an internal conductor paste on the ceramic green sheet, and a plurality of sheets including at least one ceramic green sheet printed with the internal conductor paste A method for producing a ceramic multilayer substrate comprising a step of laminating the ceramic green sheets of the above and a step of firing the obtained laminated body to obtain a sintered body, the step of printing the internal conductor paste on the ceramic green sheets On the ceramic green sheet, a step of printing an inner conductor paste on a first printing region where the first inner conductor is to be formed and a second printing region where the second inner conductor is formed; After printing the conductor paste, a step of printing the inner conductor paste on the second print area only, Characterized in that it comprises a step of drying the internalization conductor paste.

  A ceramic multilayer substrate according to the present invention includes a ceramic sintered body and first and second inner conductors that are formed at the same height in the ceramic sintered body and are not via-hole electrodes, , The thickness of the second inner conductor is different.

  According to the manufacturing method of the first invention, the step of printing the internal conductor paste on the ceramic green sheet prints the first internal conductor paste on the ceramic green sheet, and dries the first internal conductor paste. After drying the first inner conductor paste, the first inner conductor paste has a thickness different from the first inner conductor paste in a part of the area other than the area where the first inner conductor paste is printed. Since each stage for printing the second inner conductor paste and drying the second inner conductor paste is included, the first inner conductor and the first inner conductor are provided at the same height position of the obtained sintered body. And a second inner conductor having a different thickness. For this reason, for example, a first internal conductor as a capacitance forming pattern or a ground pattern that is desirably thin and a second internal conductor as an inductance pattern that is desirably thick are formed at the same height position. Therefore, it is possible to increase the density and height of the ceramic multilayer substrate, and it is possible to greatly increase the degree of freedom in circuit design inside.

  When at least one ceramic green sheet printed with at least one third inner conductor having a uniform thickness after firing is laminated in addition to the ceramic green sheet printed with the inner conductor paste, In addition to the first and second inner conductors obtained by baking the first and second inner conductor pastes, a ceramic multilayer substrate having third inner conductors formed at different height positions can be obtained. .

  When the ground electrode and / or the capacitance electrode is formed by baking the first inner conductor paste and the line conductor is formed by baking the second inner conductor paste, the first inner conductor is formed according to the present invention. By making the paste relatively thin, it is possible to form a thin ground electrode and / or a capacitive electrode, and it is possible to easily form a thick line conductor.

  When the conductive powder content of the second inner conductor paste is increased compared to the conductive powder content of the first inner conductor paste, the thickness of the second inner conductor is relatively increased. be able to. In particular, when the content of the conductive powder in the second inner conductor paste is 10% by weight or more higher than the content of the conductive powder in the first inner conductor paste, the thick second The inner conductor can be formed more reliably.

  When the first inner conductor paste contains ceramic powder, the thickness of the first inner conductor formed by baking the first inner conductor paste can be easily reduced.

  In the method for producing a ceramic multilayer substrate according to the second invention, the step of printing the internal conductor paste on the ceramic green sheet includes the first printing region on which the first internal conductor is to be printed on the ceramic green sheet, and A stage for printing the internal conductor paste on the second print area where the second internal conductor is to be formed, and a stage for printing the internal conductor paste on the second print area after further printing the internal conductor paste. Therefore, the coating thickness of the inner conductor paste in the second printing region can be made larger than the printing thickness of the inner conductor in the first printing region. Therefore, in the ceramic multilayer substrate obtained by sintering, the thickness of the second inner conductor can be made larger than the thickness of the first inner conductor, so that the degree of freedom in circuit design in the ceramic multilayer substrate is increased. In addition, it is possible to reduce the height of the ceramic multilayer substrate.

  In the ceramic multilayer substrate according to the present invention, the first and second inner conductors that are not via-hole electrodes are formed at a certain height in the ceramic sintered body, and the thicknesses of the first and second inner conductors are different. Therefore, it can be arranged at the same height position as the thick inductance forming pattern or the line conductor and the relatively thick capacitor forming pattern or ground electrode pattern. Therefore, it is possible to increase the density and the height of the electronic component units on the ceramic multilayer substrate, and to increase the degree of freedom in circuit design in the ceramic multilayer substrate.

  Hereinafter, the present invention will be clarified by describing specific embodiments of the present invention with reference to the drawings.

  FIG. 1 is a front sectional view of a ceramic multilayer substrate according to an embodiment of the present invention. The ceramic multilayer substrate 1 has a ceramic sintered body 2. The ceramic sintered body 2 is made of an appropriate insulating ceramic or dielectric ceramic. The manufacturing method of the ceramic multilayer substrate 1 will be described with reference to FIGS.

  When manufacturing the ceramic multilayer substrate 1 of the present embodiment, the ceramic green sheets 11 to 14 shown in FIG. 2 are prepared. The ceramic green sheets 11 to 14 are obtained by sheet-molding a ceramic paste containing ceramic powder made of the appropriate insulating ceramics or dielectric ceramics described above.

  Moreover, in this embodiment, in order to form an internal conductor, the 1st internal conductor paste and the 2nd internal conductor paste are prepared. The first internal conductor paste includes copper powder as the conductive powder, the same ceramic powder as in the case of the ceramic green sheets 11 to 14, the resin binder, and the solvent, and the content ratio of the conductive powder is 60 wt. %, A conductive paste having a viscosity of 60 Pm · s at 25 ° C. was prepared. In addition, as the second internal conductor paste, the conductive powder contains copper powder, a resin binder, and a solvent, the content of the conductive powder is 80% by weight, and the viscosity at 25 ° C. is 120 Pm · A conductive paste of s was prepared.

  That is, the conductive powder content in the second internal conductor paste is 20% by weight higher than the conductive powder content in the first internal conductor paste.

  On the ceramic green sheets 11 and 12 shown in FIG. 2, the first internal conductor paste was printed, and the ground electrode forming internal conductor pattern 15 and the capacitance forming internal conductor patterns 16 and 17 were printed. Further, on the upper surface of the ceramic green sheet 13, first, as shown in FIG. 3A, the first internal conductor paste is printed, and the first internal conductor pattern 18 for forming the capacitive electrode is fired. Later, the above-described inner conductor pattern 16 and ceramics were formed at overlapping positions.

  Next, as shown in FIG. 3B, the second inner conductor is formed in a part of the region different from the region where the first inner conductor pattern 18 is formed on the upper surface of the ceramic green sheet 13. The paste was printed in a coil shape to form the second inner conductor pattern 21. The second inner conductor pattern 21 was applied to a thickness of 5 to 20 μm. The second inner conductor pattern 21 constitutes a line conductor of an inductance unit as a coil conductor after baking.

  In the present embodiment, in the ceramic green sheet 13, the printing process is performed twice using the first inner conductor paste and the second inner conductor paste as described above. Accordingly, the relatively thin first inner conductor patterns 18 and 19 and the relatively thick second inner conductor patterns 21 and 22 are printed on the ceramic green sheet 13.

  On the ceramic green sheet 14, the 1st internal conductor paste was printed and the several electrode pattern 23 was formed. The plurality of electrode patterns 23 are electrically connected to the above-described internal conductor patterns 21, 22, etc. by via hole conductors (not shown).

  Next, the said ceramic green sheets 11-14 were laminated | stacked, and the laminated body was obtained by pressing in the thickness direction. By firing the thus obtained laminate, a ceramic multilayer substrate 1 shown in FIG. 1 was obtained. As shown in FIG. 1, in the ceramic multilayer substrate 1, a plurality of internal conductors 15 </ b> A, 16 </ b> A, 21 </ b> A based on the above-described internal conductor patterns 15, 16, 18, 21 are formed in the ceramic sintered body 2. Here, in order to clarify the comparison between FIG. 2 and FIG. 1, an internal conductor formed by baking the internal conductor pattern is indicated by a reference number obtained by adding A to the reference number of the internal conductor paste.

  In the ceramic sintered body 2, the above-described internal conductor pattern 15 of FIG. 2 is printed to form an internal conductor 15A as a ground electrode. The first inner conductors 16A and 18A for constituting the capacitor unit are formed above the inner conductor 15A. The inner conductors 16A and 18A overlap with each other through ceramics to constitute a capacitor. The first inner conductors 16A and 18A are formed by printing the first inner conductor paste, and the thickness thereof is relatively thin. Therefore, delamination or the like is unlikely to occur due to the formation of the first inner conductors 16A and 18A.

  On the other hand, the second inner conductor 21A formed by baking the second inner conductor paste is disposed at the same height as the inner conductor 18A. The second inner conductor 21A is a line-shaped conductor for constituting an inductor, and is formed by baking the second inner conductor paste described above. Therefore, the thickness of the inner conductor 21A is relatively thicker than the thickness of the first inner conductor 18A, and Q is sufficiently large. Therefore, it is possible to easily form a coil unit having desired characteristics by the second inner conductor 21A.

  As described above, in the ceramic multilayer substrate 1, the first inner conductor 18 </ b> A and the second inner conductor 21 </ b> A are arranged at the same height position in the ceramic sintered body 2. The thickness of 21A is made thicker than the thickness of the first inner conductor 18A, whereby the second inner conductor 21A optimum for constituting the inductance unit, and the first inner conductor as the capacitor electrode constituting the capacitor 18A can be formed to an optimum thickness in each.

  Moreover, since the first inner conductor 18A and the second inner conductor 21A are formed at the same height position, the ceramic multilayer substrate 1 incorporates a plurality of electronic component units without increasing the thickness direction dimension. Therefore, it is possible to reduce the size of the ceramic multilayer substrate, in particular, to reduce the height and increase the arrangement density of electronic components inside. In addition, the degree of freedom in designing the ceramic multilayer substrate can be increased.

  In the above embodiment, the first inner conductor pattern 18 and the second inner conductor pattern 21 shown in FIG. 2 are separately printed at the same height position. On the other hand, as shown in FIGS. 4A and 4B, first, using the first inner conductor paste, the inner conductor pattern 18 and the inner conductor pattern 21a are printed, and then the inner conductor pattern. The same first internal conductor paste may be used on 21a, printing may be performed again, and the second internal conductor pattern 21b may be laminated on the second internal conductor pattern 21a.

  That is, in the present invention, when the second inner conductor having a relatively large thickness is formed, the inner conductor paste may be printed a plurality of times in the printing region where the second inner conductor is formed. . In this case, the first inner conductor paste and the second inner conductor paste are preferably the same, but they may have different compositions. In addition, when the internal conductor paste is printed in an overlapping manner, the number of stacked layers may be three or more.

  In the above embodiment, the difference between the viscosity at 25 ° C. of the first inner conductor paste and the viscosity at 25 ° C. of the second inner conductor paste is 60 Pm · s. It has been confirmed that this viscosity difference is desirably 50 Pm · s or more. That is, when it is 50 Pm · s or more, it becomes easy to make the thickness of the second inner conductor after baking sufficiently larger than the thickness of the first inner conductor after baking.

  In the above embodiment, the first internal conductor paste contains ceramic powder, which makes it easy to reduce the thickness of the first internal conductor 18 that functions as a capacitor electrode after firing. Yes. Therefore, it is preferable that ceramic powder is contained in the first inner conductor paste as in the above embodiment.

  However, the thickness of the first inner conductor may be made relatively thin by merely reducing the content of the conductive powder without containing ceramic powder. When the ratio is different, it is desirable that the content ratio of the conductive powder in the second internal conductor paste is higher by 10% by weight or more than the content ratio of the conductive powder in the first internal conductor paste. The thickness of the second inner conductor can be relatively reliably increased.

  Furthermore, the ceramic powder contained in the first internal conductor paste is not particularly limited, but preferably, the same ceramic powder as the ceramic powder constituting the ceramic green sheet 13 is desirably used, whereby the first The adhesion between the inner conductor and the ceramic layer can be improved.

  The present invention relates to the above-mentioned ceramic multilayer substrate and a method for manufacturing the same. Here, the ceramic multilayer substrate is obtained by a ceramic-internal conductor integrated firing technique, and a plurality of ceramics are arranged with the internal conductor interposed therebetween. In addition, a wide range of ceramic electronic parts using a ceramic sintered body in which inner conductors having different thicknesses are arranged is included.

  In the above embodiment, the thick second inner conductor is configured so that the planar shape has a coil shape, but the relatively thick second inner conductor has a coil shape. It is not always necessary to have a shape, and other line conductors such as a straight line may be used.

The front sectional view of the ceramic multilayer substrate of one embodiment of the present invention. FIG. 2 is an exploded perspective view for explaining a process for manufacturing the ceramic multilayer substrate shown in FIG. 1, for explaining the shapes of a plurality of prepared ceramic green sheets and an internal conductor pattern printed thereon. Perspective view. (A), (b) is each front sectional drawing for demonstrating the process of printing the 1st internal conductor paste and the 2nd internal conductor paste on a ceramic green sheet. FIG. 9 is a front sectional view for explaining a printing process for forming a first inner conductor and a second inner conductor in another embodiment of the manufacturing method for obtaining the ceramic multilayer substrate shown in FIG. 1. Front sectional drawing which shows an example of the conventional ceramic multilayer substrate.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Ceramic multilayer substrate 2 ... Ceramic sintered body 11-14 ... Ceramic green sheet 15 ... Internal conductor pattern 15A ... Internal conductor 16, 17 ... Internal conductor pattern 16A ... Internal conductor 18, 19 ... 1st internal conductor pattern 18A ... 1st inner conductor 21, 22 ... 2nd inner conductor pattern 21a, 21b ... Internal conductor pattern 21A ... 2nd inner conductor 23 ... Conductor pattern

Claims (8)

Preparing a ceramic green sheet;
A step of printing an internal conductor paste on the ceramic green sheet;
Laminating a plurality of ceramic green sheets including at least one ceramic green sheet printed with an internal conductor paste to obtain a laminate;
In the method for producing a ceramic multilayer substrate comprising the steps of firing the laminate and obtaining a sintered body,
The step of printing the inner conductor paste on the ceramic green sheet comprises printing a first inner conductor paste on the ceramic green sheet;
A stage for drying the first inner conductor paste;
After drying the first inner conductor paste, the thickness after sintering in a part of the area other than the area where the first inner conductor paste is printed is different from the thickness of the first inner conductor paste. And a stage for printing the second inner conductor paste,
A method for producing a ceramic multilayer substrate, comprising: a stage for drying the second inner conductor paste.   The ceramic green sheet printed with the internal conductor paste is laminated with at least one ceramic green sheet printed with at least one third internal conductor having a uniform thickness after firing. Manufacturing method for ceramic multilayer substrate.   3. The ceramic multilayer substrate according to claim 1, wherein a ground electrode and / or a capacitor electrode is formed by baking of the first internal conductor paste, and a line conductor is formed by baking of the second internal conductor paste. Manufacturing method.   The ceramic multilayer substrate according to any one of claims 1 to 3, wherein the conductive powder content of the second internal conductor paste is increased compared to the conductive powder content of the first internal conductor paste. Manufacturing method.   5. The production of a ceramic multilayer substrate according to claim 4, wherein the content of the conductive powder in the second internal conductor paste is higher by 10% by weight or more than the content of the conductive powder in the first internal conductor paste. Method.   The method for producing a ceramic multilayer substrate according to claim 1, wherein the first inner conductor paste includes a ceramic powder. Preparing a ceramic green sheet;
A step of printing an internal conductor paste on the ceramic green sheet, a step of laminating a plurality of ceramic green sheets including at least one ceramic green sheet printed with the internal conductor paste, and firing the obtained laminate And a method for producing a ceramic multilayer substrate comprising a step of obtaining a sintered body,
Printing the inner conductor paste on a ceramic green sheet,
On the ceramic green sheet, printing an internal conductor paste on the first print area where the first internal conductor is to be formed and the second print area where the second internal conductor is formed;
After printing the inner conductor paste, the step of printing the inner conductor paste on the second print area only,
And a step of drying the printed internal conductor paste. A method for producing a ceramic multilayer substrate. Ceramic sintered body,
A ceramic multilayer which is formed at the same height in a ceramic sintered body, includes first and second inner conductors which are not via-hole electrodes, and the first and second inner conductors have different thicknesses. substrate.

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