JP2005217256A - Lamination ceramic electronic component and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lamination ceramic electronic component which surely enables formation of an interlayer connection via hole by a connection land of a minimum area, and to provide its manufacturing method. <P>SOLUTION: A coil conductor pattern 3a has a connection land 5 in an end. An interlayer connection via hole 4 is provided unevenly to the rectangular connection land 5, and has an extension 5a which is at least 10 μm long from an opening of the interlayer connection via hole 4. Since a conductive paste is subjected to screen print on a ceramic green sheet 2, the coil conductor pattern 3a is formed so that the connection land 5 overlaps with a through hole provided to the ceramic green sheet 2, and at the same time the interlayer connection via hole 4 is formed by charging the through hole with the conductive paste. At this time, in the screen print, squeezing is carried out in a direction (shown by an arrow K) parallel with an extension direction of the extension 5a from the extension part 5a toward the through hole. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a multilayer ceramic electronic component, in particular, a multilayer ceramic electronic component such as a multilayer inductor or a multilayer LC filter, and a method for manufacturing the same.

  Conventionally, a multilayer inductor described in Patent Document 1 is known. FIG. 4 is an exploded perspective view of the multilayer inductor 101. The multilayer inductor 101 is formed by stacking a plurality of ceramic sheets 102 made of ferrite or the like to form a multilayer body, and electrically connecting the coil conductor patterns 103 via interlayer connection via holes 104 provided in the ceramic sheet 102. A coil L2 is formed. The coil conductor pattern 103 is formed by applying a conductive paste to the ceramic sheet 102 after the through holes are formed by screen printing. At the time of this application, the through holes are filled with the conductive paste, and the interlayer connection A via hole 104 is formed.

  The coil conductor pattern 103 is formed in a substantially U shape, and has a connection land 105 for connection to the interlayer connection via hole 104 at the end thereof. Further, the spiral coil L2 is drawn out to both ends of the multilayer body through interlayer connection via holes 104 and connection lands 105 provided in the outer layer ceramic sheet 102.

Here, the conductive paste is screen-printed on the ceramic sheet 102 to form the connection lands 105 so as to overlap the through holes provided in the ceramic sheet 102, and the through holes are filled with the conductive paste and the via holes for interlayer connection are formed. In forming 104, if the area of the connection land 105 is small, it is known that the through hole is not sufficiently filled with the conductive paste, and the interlayer connection via hole 104 cannot be reliably formed. It is known that when the area of the connection land 105 is increased, the conductive paste is surely filled in the through hole, but it is difficult to increase the area of the connection land within a limited component size range. In particular, as shown in FIG. 4, when the connection land 105 is large in all directions with respect to the interlayer connection via hole 104, the difficulty is remarkable.
JP 2000-286125 A

  SUMMARY OF THE INVENTION An object of the present invention is to provide a multilayer ceramic electronic component capable of reliably forming an interlayer connection via hole with a connection land having an area as small as possible, and a method for manufacturing the same.

  In order to achieve the above object, a multilayer ceramic electronic component according to the present invention is a multilayer ceramic electronic component configured by laminating a plurality of ceramic sheets on which an internal conductor pattern is printed, and the internal conductor pattern has a connection land. The internal conductor patterns of different layers are electrically connected by the interlayer connection via hole provided in the connection land, and the connection land has an extended portion having a length of 10 μm or more from the opening of the interlayer connection via hole. It is characterized by being.

  The connection land is, for example, any one of a substantially rectangular shape, a substantially oval shape, and a substantially oval shape, and the width in the direction perpendicular to the extending direction of the extending portion of the connecting land has a dimension equal to or larger than the diameter of the via hole for interlayer connection. Yes.

  In the method for manufacturing a multilayer ceramic electronic component according to the present invention, the conductive land is screen-printed on the ceramic sheet to form a connection land so as to overlap the through hole provided in the ceramic sheet, and the through hole is electrically conductive. An interlayer connection via hole is formed by filling with paste, and during screen printing, squeezing is performed in a direction parallel to the extending direction of the extending portion and in a direction from the extending portion toward the through hole.

  According to the present invention, since the connection land has an extended portion having a length of 10 μm or more from the opening of the via hole for interlayer connection, the amount of the conductive paste applied is large, and the through paste is sufficiently filled with the conductive paste. be able to. On the other hand, since the width in the direction orthogonal to the extending direction of the extending portion of the connection land is set to the minimum necessary size, the area of the connection land can be reduced.

  Further, when the connection land is formed by screen printing on the ceramic sheet, and the via hole for interlayer connection is formed by filling the through hole with the conductive paste, the direction is parallel to the extending direction of the extending portion and By performing squeezing in the direction from the stretched part toward the through hole, the amount of conductive paste discharged to the connection land increases, and the through hole is sufficiently filled with the conductive paste to reliably form the via hole for interlayer connection. Can do.

  Hereinafter, embodiments of a multilayer ceramic electronic component and a manufacturing method thereof according to the present invention will be described with reference to the accompanying drawings.

  As shown in FIG. 1, the multilayer inductor 1 includes a ceramic green sheet 2 provided with a coil conductor pattern 3a, a lead conductor pattern 6, and interlayer connection via holes 4, coil conductor patterns 3b and 3c, and interlayer connection via holes 4. The ceramic green sheet 2 provided, the ceramic green sheet 2 provided with the coil conductor pattern 3d and the lead conductor pattern 7, the ceramic green sheet 2 for the outer layer not provided with the conductor pattern in advance, and the like.

  The ceramic green sheet 2 is obtained by kneading, for example, an Fe—Ni—Cu ferrite ceramic powder or dielectric ceramic powder together with a binder or the like into a sheet shape by a method such as a doctor blade method.

  Each of the coil conductor patterns 3a to 3d has a connection land 5 at an end, and the coil conductor patterns 3a to 3d of different layers are electrically connected in series by the interlayer connection via hole 4 provided in the connection land 5 and spiral. The coil L1 is formed.

  As shown in FIG. 2, the connection land 5 has, for example, any one of a substantially rectangular shape, a substantially oval shape, and a substantially oval shape. In this embodiment, the connection land 5 is rectangular. The interlayer connection via hole 4 is provided at an offset position with respect to the connection land 5, and has an extended portion 5 a having a length W of 10 μm or more from the opening of the interlayer connection via hole 4. The width D in the direction orthogonal to the extending direction of the extending portion 5 a of the connection land 5 has a dimension equal to or larger than the diameter d of the interlayer connection via hole 4. Here, the width D is formed wider than the width of the coil conductor pattern 3a.

  The coil conductor patterns 3a to 3d and the lead conductor patterns 6 and 7 are made of Ag, Pd, Cu, Au, alloys thereof, or the like, and are formed by a screen printing method. Further, the interlayer connection via hole 4 is formed by forming a through hole in the ceramic green sheet 2 using a laser beam or the like and filling the through hole with a conductive paste such as Ag, Pd, Cu, Au, or an alloy thereof. It is formed.

  That is, the conductive paste is screen-printed on the ceramic green sheet 2 to form the coil conductor patterns 3a to 3c so that the connection lands 5 overlap the through holes provided in the ceramic green sheet 2, and at the same time, the conductive paste is formed in the through holes. Then, the via hole 4 for interlayer connection is formed. At this time, screen printing performs squeezing in a direction parallel to the extending direction of the extending portion 5a and in a direction from the extending portion 5a toward the through hole (the direction of the arrow K in FIGS. 1 and 2). As a result, a large amount of conductive paste is applied to the extending portions 5a of the connection lands 5 through the screen plate and filled into the through holes.

  Both ends of the spiral coil L1 are electrically connected to the lead conductor patterns 6 and 7. The lead conductor patterns 6 and 7 are exposed on the left and right sides of the sheet 2, respectively.

  Each sheet 2 is stacked and pressure-bonded, and then fired integrally to form a laminate 11 having a rectangular parallelepiped shape as shown in FIG. Input / output external electrodes 12 and 13 are formed on the left and right end faces of the laminate 11. The external electrodes 12 and 13 are formed by a method such as coating baking, sputtering, or vapor deposition. Lead conductor patterns 6 and 7 are connected to the external electrodes 12 and 13, respectively. Further, Ni plating and Sn plating are performed on the surfaces of the external electrodes 12 and 13 for the purpose of improving solderability.

  In the multilayer inductor 1 having the above configuration, since the connection land 5 has the extending portion 5a having a length of 10 μm or more from the opening of the interlayer connection via hole 4, the amount of conductive paste applied is large, and the through hole is formed in the through hole. The conductive paste can be sufficiently filled. On the other hand, since the width D in the direction orthogonal to the extending direction of the extending portion 5a of the connection land 5 is set to the minimum necessary dimension, the area of the connection land 5 is compared with the conventional connection land 105 shown in FIG. To make it smaller.

  More specifically, as shown in FIG. 2, the diameter d of the interlayer connection via hole 4, the length W from the opening of the interlayer connection via hole 4 to the end of the extension portion 5a of the connection land 5, and the connection The multilayer inductor 1 (Examples 1 to 8) in which the width D in the direction orthogonal to the extending direction of the extending part 5a of the land 5 was changed was created and evaluated. The evaluation results are shown in Table 1-1. In Table 1-2, Comparative Example 1 and Comparative Example 2 are described.

  From Table 1-1 and Table 1-2, when the length W is 10 μm or more, the disconnection rate of the interlayer connection via hole 4 is 0%, and the disconnection rate by the surge test (± 30 kV × 20 times) is also 0%. Met. That is, if the length W is 10 μm or more, the conductive paste is discharged to the connection land 5 by performing squeezing in a direction parallel to the extending direction of the extending portion 5a and in a direction from the extending portion 5a toward the through hole. It can be seen that the amount increases, and the through hole is sufficiently filled with the conductive paste to reliably form the interlayer connection via hole 4.

  In addition, this invention is not limited to the said Example, It can change variously within the range of the summary. Examples of the multilayer ceramic electronic component include a multilayer LC filter and a multilayer impedance element in addition to the multilayer inductor.

1 is an exploded perspective view showing an embodiment of a multilayer ceramic electronic component according to the present invention. FIG. 2 is a plan view for explaining a method for manufacturing the multilayer ceramic electronic component shown in FIG. 1. FIG. 2 is an external perspective view of the multilayer ceramic electronic component shown in FIG. 1. The exploded perspective view which shows a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Multilayer inductor 2 ... Ceramic green sheet 3a-3d ... Coil conductor pattern 4 ... Via-hole for interlayer connection 5 ... Connection land 5a ... Extension part L1 ... Spiral coil W ... Length of extension part D ... Connection land width d ... Diameter of via hole for interlayer connection

Claims (4)

In a multilayer ceramic electronic component constructed by laminating a plurality of ceramic sheets printed with an internal conductor pattern,
The internal conductor pattern has a connection land, and the internal conductor patterns of different layers are electrically connected to each other by an interlayer connection via hole provided in the connection land, and the connection land is 10 μm from the opening of the interlayer connection via hole. A multilayer ceramic electronic component having an extending portion having the above length.   2. The multilayer ceramic electronic component according to claim 1, wherein a width in a direction orthogonal to an extending direction of the extending portion of the connection land has a dimension equal to or larger than a diameter of the interlayer connection via hole.   3. The multilayer ceramic electronic component according to claim 1, wherein the connection land has any one of a substantially rectangular shape, a substantially oval shape, and a substantially oval shape. 4. A method for producing a multilayer ceramic electronic component according to any one of claims 1 to 3,
The connection lands are formed so as to overlap the through holes provided in the ceramic sheet by screen-printing the conductive paste on the ceramic sheets, and the via holes for interlayer connection are formed by filling the through holes with the conductive paste. A method of manufacturing a multilayer ceramic electronic component, wherein squeezing is performed in the direction parallel to the stretching direction of the stretched portion and in the direction from the stretched portion toward the through hole during the screen printing. .

Images