JP2007134568A - Stacked coil component, and method of manufacturing same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact stacked coil component which is easily manufactured and has an excellent electric characteristic, and to provide a method of manufacturing the same. <P>SOLUTION: By the manufacturing method, a coil conductor 13 is printed on ceramic green sheets 21 and also coil conductive sheets 23 are manufactured with a conductive paste filled in a through-hole 22. Besides, through-hole sheets 25 are manufactured, where a through-hole 24 is formed in a ceramic green sheet 21'. The coil conductive sheets 23 are stacked so as to allow the coil conductors 13 to be successively electrically connected with the use of a via hole conductor 22a including the conductive paste filled in the through-hole 22. A stacked body 26 is formed by stacking the through-hole sheets 25 at the upper and lower sides of the coil conductive sheets 23. Then the stacked body 26 is bonded with pressure. In the pressure bonding process, a part of the via hole conductor 22a invades the through-hole 24 so that the invading conductor forms the via hole conductor 24a for drawing out both the ends of the coil to an outer part. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a laminated coil component and a manufacturing method thereof, and more particularly to a laminated coil component manufactured by laminating ceramic green sheets and a manufacturing method thereof.

  Generally, a printing method or a sheet method is known as a method for manufacturing a multilayer electronic component such as a multilayer capacitor or a multilayer inductor. In the printing method, a laminate is produced by alternately printing a slurry of calcined powder of a magnetic ceramic material and a conductive paste. In the sheet construction method, a ceramic slurry is formed into a green sheet by a doctor blade method or the like, a conductive paste is applied thereon and dried, and a green sheet with a conductor is laminated to produce a laminate.

  Compared with the sheet method, the printing method does not require a ceramic green sheet forming step or a lamination step, and has an advantage that the manufacturing process is relatively simple. On the other hand, the sheet method is superior in accuracy compared to the printing method, and at present, manufacturing by the sheet method is mainly used for particularly small products.

  Patent Document 1 discloses a multilayer inductor (multilayer coil component) manufactured by the sheet method. As shown in FIG. 11, this multilayer inductor has insulator layers 1a to 1g made of a magnetic material or a dielectric, and coil conductors 2a to 2g are formed on these insulator layers 1a to 1g by printing or the like. Has been. Also, via-hole conductors 3a to 3f are formed in the insulator layers 1a to 1f, and these via-hole conductors 3a to 3f are the same steps as the formation of the coil conductors in the holes previously formed in the ceramic green sheet by laser irradiation or the like. And filled with a conductive paste.

  The via-hole conductors 3a to 3f electrically connect the ends of the coil conductors adjacent to each other in the stacking direction. Of the coil conductors 2a to 2g, the uppermost and lowermost coil conductors 2a and 2g are respectively provided with lead electrode portions 4a and 4b serving as winding start end portions and winding end end portions, respectively, on the end surfaces of the multilayer body. Is formed.

  When manufacturing the multilayer inductor, as shown in FIG. 12A, a ceramic green sheet in which a large number of coil conductors 2a to 2g are respectively formed in a matrix shape is formed into an upper cover insulating layer 1i, 1j and a ceramic green sheet to be the lower cover insulating layer 1k, and are stacked and pressed by a press P from above. Thereafter, through a cutting process and a baking process for cutting into individual chips, as shown in FIG. 12B, external electrodes 5a and 5b are formed by applying, baking, plating, etc., conductive paste on both end faces of the chip. is doing.

  By the way, in recent years, with the miniaturization of electronic devices, the demand for miniaturization of laminated electronic components and the like used therein has become more severe. With such miniaturization, the following problems have arisen.

  That is, in order to obtain a small-sized multilayer inductor having a large inductance, a small DC resistance, the thickness Ts of the ceramic green sheet (see FIG. 12A) is reduced while the thickness Tc of the coil conductor is increased. It is necessary to reduce the DC resistance. However, since the ceramic green sheets to be the insulator layers 1a to 1k are in a flexible state including a certain amount of binder in order to ensure adhesion with other ceramic green sheets, these sheets are laminated. When crimping, the sheet is crushed. In contrast, the coil conductors 2a to 2g and the via hole conductors 3a to 3f made of silver or a silver alloy powder paste have a relatively small amount of shrinkage due to compression. Therefore, the coil conductors 2a to 2g and the via-hole conductors 3a to 3f are difficult to compress.

  As a result, pressure is applied to the via-hole conductors 3a to 3f and the coil conductors 2a to 2g around the respective via-hole conductors 3a to 3f. In particular, when Tc ≧ Ts, the pressure increases. Then, stress is generated by the strong pressure, and the inductance decreases. Further, the coil conductors 2a to 2g and the via-hole conductors 3a to 3f are crushed by a strong pressure, and the coil diameter is reduced, whereby the inductance is further reduced. For this reason, there has been a problem that the shape is inevitably increased when trying to obtain a large inductance.

Further, when the coil conductor is drawn out in a direction orthogonal to the coil axis direction, as shown in FIG. 12 (A), the portion where the coil conductors 2a to 2g are not formed (the portion that becomes the end surface portion of the laminate) ) Has a gap g before compression, and as a result of crimping, as shown in FIG. 12B, the extraction electrode portions 4a and 4b bend downward and upward, respectively, and the extraction electrode portions 4a and 4b and the coil conductor 2b , 2f via-hole conductors 3b, 3e may be short-circuited at the portions indicated by reference numerals 6 and 7, respectively, resulting in a problem that the manufacturing yield is lowered.
JP 2003-209016 A

  SUMMARY OF THE INVENTION An object of the present invention is to provide a small multilayer coil component that is easy to manufacture and has excellent electrical characteristics, and a method for manufacturing the same.

In order to achieve the above object, a method for manufacturing a laminated coil component according to the present invention includes:
Producing a ceramic green sheet;
A first through hole is formed at a predetermined position of the first ceramic green sheet, and a coil conductor is formed on the first ceramic green sheet with a conductive paste, and the conductive paste is formed in the first through hole. Filling a coil conductor sheet,
Forming a second through hole at a predetermined position of the second ceramic green sheet to produce a through hole sheet;
The coil conductor sheet and the through-hole sheet are laminated and pressure-bonded to allow the conductive paste to enter the second through-hole, and the coil conductor is electrically connected to form a coil. Forming, and
Firing the ceramic laminate to produce a sintered body unit;
Forming an external electrode electrically connected to the coil in the sintered body unit;
It is provided with.

  In the manufacturing method according to the present invention, since the second through hole of the through hole sheet is not filled with the conductive paste, the first through hole adjacent to the second through hole when the ceramic laminate is pressure-bonded. The conductive paste filled in the hole enters the second through hole. That is, the second through hole serves as an absorption portion that receives the conductive paste when the ceramic laminate is pressed. As a result, the pressure applied to the portion close to the first through hole of the coil conductor sheet and the peripheral portion of the second through hole of the through hole sheet is relieved, the stress in these portions is reduced, and the decrease in inductance is suppressed. Is done. Moreover, the fall of the inductance by the coil diameter becoming small is also suppressed.

  In the manufacturing method according to the present invention, the coil conductor sheets are laminated so that the lamination direction thereof coincides with the coil axial direction of the coil, and the through-hole sheets are positioned at the lowermost layer portion and the uppermost layer portion of the ceramic laminate. It is preferable to laminate them. The conductive paste (first via-hole conductor) corresponding to both ends of the coil enters the second through-hole formed in the through-hole sheet when the ceramic laminate is pressure-bonded. The conductive paste that has penetrated into the second through hole functions as a lead electrode portion, and both ends of the coil are electrically connected to the external electrode.

  The second through hole is preferably formed larger than the first through hole. When the ceramic laminate is crimped, the capacity of the second through-hole that receives the conductive paste corresponding to both ends of the coil is increased, and the portion of the coil conductor sheet adjacent to the first through-hole and the through-hole sheet The pressure applied to the peripheral portions of the second through hole is further relaxed, and the stress in these portions is further reduced.

The laminated coil component according to the present invention is
A coil conductor is formed with a ceramic layer formed by laminating, pressing and firing the ceramic green sheets, and the coil conductor is electrically connected by a via-hole conductor formed in the ceramic layer to form a coil inside. Comprising a sintered body unit formed of
The coil is electrically connected to an external electrode formed in the sintered body unit via an extraction electrode portion;
In the coil conductor, a portion close to the via-hole conductor is inclined with respect to the laminated surface of the ceramic layer,
It is characterized by.

  In the multilayer coil component according to the present invention, the pressure applied to the portion of the coil laminate close to the via hole conductor is relieved by the inclination of the portion of the coil conductor close to the via hole conductor. Thereby, the fall of an inductance is suppressed and the short circuit defect between coil conductors is also eliminated.

  In the laminated coil component according to the present invention, it is preferable that the coil conductor is inclined with respect to the laminated surface of the ceramic layer at a portion close to the lead electrode portion. The pressure applied to the portion adjacent to the via-hole conductor in the ceramic laminate is relieved, and the connection process between the extraction electrode portion and the coil conductor is facilitated.

  Moreover, it is preferable that each coil conductor pattern has a length corresponding to 1/2 turn. The coil conductor has a 180-degree rotationally symmetric pattern shape, and the via hole conductors are also formed in two concentrated locations, so that pressure is concentrated on the via hole conductors. Is mitigated to suppress a decrease in inductance, and a short circuit between coil conductors is eliminated.

  Moreover, the external electrode may be formed on the end face orthogonal to the coil axis direction of the sintered body unit. Since the external electrode faces only the coil conductors located at both ends of the coil formed in the sintered body unit, the facing area between the external electrode and the coil is reduced, and the stray capacitance is reduced.

  According to the present invention, since the pressure applied to the peripheral portion of the via-hole conductor is relieved, a reduction in inductance is suppressed, and a laminated coil component having excellent electrical characteristics can be obtained. Further, short-circuit defects between coil conductors are eliminated, and the yield of products at the time of manufacture is improved. Furthermore, since both ends of the coil are electrically connected to the external electrodes by the conductive paste that has entered the second through hole, the manufacturing process is simplified and the manufacturing cost can be reduced.

  Hereinafter, embodiments and examples of the laminated coil component and the manufacturing method thereof according to the present invention will be described. The drawings to be referred to in the description of each embodiment show one unit obtained as a result of cutting after laminating formed large-area ceramic green sheets (mother sheets).

(Refer 1st Embodiment and FIGS. 1-4)
The manufacturing method of the laminated coil component which is 1st Embodiment is shown in FIGS. 1-3, and the typical longitudinal section of the finished product of a laminated coil component is shown in FIG. 4, respectively.

  As shown in FIG. 4, in the laminated coil component 10, a spiral coil 12 is formed in a ceramic sintered body unit 11 having a chip shape. In the coil 12, the coil conductors 13 formed in the sintered body unit 11 are electrically connected sequentially in series by the first via-hole conductor 22a. The coil conductor 13 is formed on the ceramic layer 17 in a predetermined pattern shape.

  The coil 12 includes external electrodes 18 formed on both end faces parallel to the stacking direction by second via-hole conductors 24a formed on the ceramic layer 15 positioned at the uppermost and lowermost parts of the sintered body unit 11. 18 respectively.

  The laminated coil component 10 having the internal structure described above can be manufactured as follows. First, the ferrite calcined powder is dispersed in water and pulverized to produce a ceramic slurry. From this ceramic slurry, a ceramic green sheet is formed by a pulling method or a doctor blade method. In the formed ceramic green sheet, as shown in FIG. 1, a first through hole 22 is formed at a predetermined position corresponding to one end of the coil conductor 13 of the ceramic green sheet 21 by irradiation with a carbon dioxide laser or the like.

  Next, an L-shaped coil conductor 13 is screen-printed on the ceramic green sheet 21 using a conductive paste mainly composed of Ag so that the first through hole 22 is located at one end. Simultaneously with this printing, the first through hole 22 is filled with a conductive paste to form a first via-hole conductor 22a. The coil conductor 13 has a length corresponding to 1/2 turn. In this manner, the coil conductor sheet 23 in which the L-shaped coil conductor 13 is printed on the main surface and the first through hole 22 is filled with the conductive paste is produced.

  Further, the second through hole 24 is formed on the ceramic green sheet 21 ′ different from the above by irradiation with a carbon dioxide gas laser or the like to produce the through hole sheet 25. The second through holes 24 are respectively formed at positions corresponding to the end portions of the coil conductor 13 corresponding to the winding start end portion and the winding end end portion of the coil 12 (see FIG. 4). Further, the second through hole 24 is formed so that its diameter is the same as or larger than the diameter of the first through hole 22. In the first embodiment, the second through hole 24 is formed large.

  Thereafter, as shown in FIG. 2, the coil conductor sheet 23 is laminated so that the coil conductor 13 is electrically connected in series sequentially by the first via-hole conductor 22a to form the coil 12 shown in FIG. And the through-hole sheet 25 is further laminated | stacked and crimped | bonded to the upper side and lower side of the laminated | stacked coil conductor sheet 23, and the ceramic laminated body 26 is formed (refer FIG. 3).

  In this crimping step, the ceramic green sheets 21 and 21 ′ are in a flexible state including a certain amount of binder to ensure adhesion, but the second through hole 24 of the through hole sheet 25 has a conductive paste. Therefore, the conductive paste (the conductive paste filled in the first through-holes 22 positioned immediately above and immediately below the second through-holes 24) that has a relatively small amount of shrinkage due to compression enters. The conductive paste that has entered the second through hole 24 forms a second via-hole conductor 24a for drawing the coil 12 to the outside (see FIG. 3). The conductive paste that has entered the second through-hole 24 is a conductive paste that has been dried after screen printing.

  Further, by the penetration of the conductive paste into the second through-hole 24, the coil conductor 13 is gently inclined with respect to the laminated surface by drawing a gentle slope around the first via-hole conductor 22a. The pressure applied to the part close to the through hole 22 and the peripheral part of the second through hole 24 is relieved. On the other hand, the inclination of the coil conductor 13 in the portion adjacent to the second via-hole conductor 24a that functions as an extraction electrode is relatively large. Note that not all of the coil conductors 13 need to be inclined, and the pressure can be relieved by inclining some of the coil conductors 13.

  Next, the ceramic laminate 26 produced through the above steps is cut into one unit and fired. Thereby, the sintered compact unit 11 in which the coil 12 was formed is obtained. Thereafter, after the sintered body unit 11 is polished in the wet barrel polishing step, the laminated body having the internal structure shown in FIG. 4 is obtained through the Ag external electrode forming step and the wet plating step of the Ag external electrode. The coil component 10 can be obtained.

  In the first embodiment, the second through hole 24 has a diameter larger than that of the first through hole 22 and is not filled with a conductive paste. Therefore, when the ceramic laminated body 26 is pressure-bonded, the second through hole 24 becomes an absorption portion that receives the conductive paste filled in the adjacent first through hole 22. Thereby, the pressure applied to the portion adjacent to the first through hole 22 and the peripheral portion of the second through hole 24 is relieved, the stress in these portions is reduced, and the decrease in inductance can be suppressed. Further, since the pressure is relieved, it is possible to suppress a decrease in inductance due to a decrease in the coil diameter.

  In addition, since the coil 12 is electrically connected to the external electrode 18 by the conductive paste (second via-hole conductor 24a) that has penetrated into the second through hole 24, the pattern of the extraction electrode portion becomes unnecessary, and the laminated coil component The manufacturing process can be simplified and the manufacturing cost can be reduced.

(See the second embodiment, FIG. 5)
FIG. 5 shows a schematic longitudinal section of the laminated coil component according to the second embodiment. This laminated coil component 10a is the laminated coil component 10 described as the first embodiment, and external electrodes 18 are formed on the uppermost layer and the lowermost layer of the sintered body unit 11 and on the periphery thereof. It is what I did. In FIG. 5, portions corresponding to those in FIG. 4 are denoted by corresponding reference numerals, and redundant description is omitted.

  In the second embodiment, the external electrode 18 is positioned at an end surface orthogonal to the coil axis direction of the sintered body unit 11, that is, directly above and directly below the uppermost layer and the lowermost ceramic layer 15 of the sintered body unit 11. Therefore, it only faces the coil conductors 13 located at both ends of the coil 12 formed in the sintered body unit 11. Thereby, the facing area between the external electrode 18 and the coil 12 is reduced, the stray capacitance is reduced, and the high frequency characteristics of the laminated coil component are improved.

(Refer to the third embodiment, FIGS. 6 and 7)
As shown in FIGS. 6 and 7, the multilayer coil component according to the third embodiment is the same as the multilayer coil component 10 described as the first embodiment, except that the coil conductors 13 positioned at both ends of the coil 12 are external electrodes 18. The ceramic green sheet 32 and the cover sheet 33 on which the extraction electrode portion 31 for electrical connection is formed are laminated on the upper and lower surfaces of the upper and lower through-hole sheets 25. In FIGS. 6 and 7, portions corresponding to those in FIGS. 1 to 4 are denoted by corresponding reference numerals, and redundant description is omitted.

  In the third embodiment, the conductive paste enters the second through hole 24 from both the upper and lower directions of the first via-hole conductor 22a and the extraction electrode portion 31 when the ceramic laminate 26 is crimped. Thereby, the electrical connection between the coil conductor 13 and the extraction electrode portion 31 is reliably performed, and the reliability of the electrical extraction from both ends of the coil 12 to the external electrode 18 is increased. Even if the conductor (leading electrode portion 31) is pulled out in the direction orthogonal to the coil axis direction, the pressure around the second via-hole conductor 24a is relieved, so that a large pressure is applied to the conductor (leading electrode portion 31). And no short circuit occurs.

  In addition, in this 3rd Embodiment, it can also be set as the structure which pulls out what is called an intermediate | middle tap from the coil 12 by inserting the ceramic green sheet 32 in the intermediate part of the coil conductor sheet 23. FIG.

(Example 1, Comparative Example 1, Comparative Example 2)
Next, Example 1 and Comparative Examples 1 and 2 will be shown and described in more detail. The laminated coil component 10 (Example 1) of 1st Embodiment demonstrated in FIGS. 1-4 by the process of (1)-(7) shown below was manufactured.

(1) First, a Ni—Cu—Zn ferrite powder (permeability μ = 400), a dispersant, a binder and a solvent are kneaded to prepare a slurry, and a thickness of 20 μm is formed on a carrier film by a doctor blade method. Long ceramic green sheets 21 and 21 'were formed.
(2) A first through hole 22 having a diameter of 50 μm was formed in the ceramic green sheet 21 produced in the step (1) by irradiation with a carbon dioxide gas laser.
(3) Thickness having a length corresponding to 1/2 turn by screen printing using a conductive paste made of Ag on the ceramic green sheet 21 in which the first through hole 22 is formed in the step (2). Printed the coil conductor 13 having a thickness of 25 μm, and at the same time as the printing, the first through-hole 22 was filled with a conductive paste to produce a coil conductor sheet 23. Then, the printed and filled conductive paste was dried.
(4) A second through-hole 24 having a diameter of 100 μm was formed on another ceramic green sheet 21 ′ produced in the step (1) by a carbon dioxide gas laser to produce a through-hole sheet 25.
(5) After laminating the coil conductor sheet 23 obtained in the step (3) and laminating the two through-hole sheets 25 produced in the above (4) on the upper and lower sides, 1.0 ton internal / cm ² of crimped with pressure, and a coil conductor 13 sequentially electrically connected in series by the conductive paste in the first through hole 22 (first via hole conductors 22a), and cut for each unit A chip-shaped ceramic laminate 26 in which the coil 12 having 8.5 turns was formed was obtained.
(6) The ceramic laminate 26 obtained in the step (5) was baked at a temperature of 870 to 900 ° C. through the binder removal step, and the sintered body unit 11 was produced.
(7) After the sintered body unit 11 obtained in the step (6) is polished in the wet barrel polishing step, the Ag external electrode is baked, the surface of the Ag external electrode is Ni / Sn plated, and the size is 0 A multilayer coil component 10 having a size of 0.6 × 0.3 × 0.3 mm was obtained.

  On the other hand, in the manufacturing process of Example 1, the step (4) is omitted, that is, instead of the through-hole sheet 25 in which the second through-hole 24 is formed, as shown in FIGS. A laminated coil component (Comparative Example 1) is manufactured using the ceramic green sheet 21 formed with the extraction electrode portion 41 for drawing out to the external electrode 18 and the ceramic green sheet 42 for the cover (both are not formed with through holes). did. In Comparative Example 1, the thickness of the coil conductor 13 was 10 μm.

  Furthermore, a laminated coil component (Comparative Example 2) in which the thickness of the coil conductor 13 was 25 μm was manufactured by the manufacturing process of Comparative Example 1.

  For each sample of Example 1, Comparative Example 1 and Comparative Example 2, the coil impedance Z (Ω) (absolute value), DC resistance Rdc (mΩ) at 100 MHz, and the number of short-circuit defects per 1000 samples were examined. The results shown in the following Table 1 were obtained.

  As can be seen from Table 1, it can be seen that in the laminated coil component of Example 1, the DC resistance Rdc is smaller than in the laminated coil components of Comparative Example 1 and Comparative Example 2. Further, in the coil of Example 1, the impedance Z is also higher than that of the coil of Comparative Example 2. Thereby, in the laminated coil component of Example 1, a coil having excellent electrical characteristics can be obtained.

(Other embodiments)
The laminated coil component and the manufacturing method thereof according to the present invention are not limited to the above-described embodiments and examples, and various configurations can be made within the scope of the gist thereof.

  For example, each coil conductor 13 has been described as having a length corresponding to ½ turn with respect to the total number of turns of the coil, but even if the length is equivalent to ¼ turn or ¾ turn. Good. Further, as a material of the sintered body unit, a non-magnetic ceramic material can be used in addition to a magnetic ceramic material such as Ni—Zn—Cu ferrite, Ni—Zn ferrite, and Cu—Zn ferrite.

  Further, in the embodiment, the coil conductor sheets are stacked on the top and bottom of the coil conductor sheet in which the through-hole sheets are laminated. That is, in addition to the through-hole sheets disposed above and below the coil conductor sheet, a through-hole sheet may be disposed between the plurality of coil conductor sheets. Or you may arrange | position a through-hole sheet | seat only between several coil conductor sheets, without arrange | positioning a through-hole sheet | seat above and below a coil conductor sheet. Furthermore, the number of through-hole sheets stacked may be one or more, and may be arranged only on one of the upper and lower sides of the coil conductor sheet.

It is a disassembled perspective view which shows the laminated coil component which is 1st Embodiment. It is a fragmentary longitudinal cross-section which shows the crimping | compression-bonding of the ceramic laminated body in 1st Embodiment. It is a fragmentary longitudinal cross-section which shows the crimping | compression-bonding of the ceramic laminated body in 1st Embodiment. It is a longitudinal cross-sectional view which shows typically the laminated coil component which is 1st Embodiment. It is a longitudinal cross-sectional view which shows typically the laminated coil component which is 2nd Embodiment. It is a fragmentary sectional view which shows the crimping | compression-bonding of the ceramic laminated body in 3rd Embodiment. It is a fragmentary sectional view which shows after the crimping | compression-bonding of the ceramic laminated body in 3rd Embodiment. FIG. 6 is a partial longitudinal sectional view showing a ceramic laminate body in Comparative Example 1 before being crimped. 6 is a partial longitudinal sectional view showing a ceramic laminated body in Comparative Example 1 after being crimped. FIG. 5 is a longitudinal sectional view showing a laminated coil component that is Comparative Example 1. FIG. It is a disassembled perspective view which shows the conventional laminated coil components. The ceramic laminated body in the conventional laminated coil components is shown, (A) is a longitudinal cross-sectional view of the ceramic laminated body before crimping, (B) is a longitudinal sectional view of the ceramic laminated body after crimping.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10, 10a ... Laminated coil component 11 ... Sintered body unit 12 ... Coil 13 ... Coil conductor 14 ... 1st via-hole conductor 15 ... Ceramic layer 16 ... 2nd via-hole conductor 17 ... Ceramic layer 18 ... External electrode 21, 21 ' ... Ceramic green sheet 22 ... first through hole 22a ... first via hole conductor 23 ... coil conductor sheet 24 ... second through hole 24a ... second via hole conductor 25 ... through hole sheet 26 ... ceramic laminate 31 ... drawer Electrode part

Claims (7)

Producing a ceramic green sheet;
A first through hole is formed at a predetermined position of the first ceramic green sheet, and a coil conductor is formed on the first ceramic green sheet with a conductive paste, and the conductive paste is formed in the first through hole. Filling a coil conductor sheet,
Forming a second through hole at a predetermined position of the second ceramic green sheet to produce a through hole sheet;
The coil conductor sheet and the through-hole sheet are laminated and pressure-bonded to allow the conductive paste to enter the second through-hole, and the coil conductor is electrically connected to form a coil. Forming, and
Firing the ceramic laminate to produce a sintered body unit;
Forming an external electrode electrically connected to the coil in the sintered body unit;
A method for manufacturing a laminated coil component, comprising:   Laminating the coil conductor sheet so that the laminating direction thereof coincides with the coil axial direction of the coil, and laminating the through-hole sheet so as to be positioned at the lowermost layer portion and the uppermost layer portion of the ceramic laminate. The manufacturing method of the laminated coil components of Claim 1 characterized by these.   The method for manufacturing a laminated coil component according to claim 1, wherein the second through hole is formed larger than the first through hole. A coil conductor is formed with a ceramic layer formed by laminating, pressing and firing the ceramic green sheets, and the coil conductor is electrically connected by a via-hole conductor formed in the ceramic layer to form a coil inside. Comprising a sintered body unit formed of
The coil is electrically connected to an external electrode formed in the sintered body unit via an extraction electrode portion;
In the coil conductor, a portion close to the via-hole conductor is inclined with respect to the laminated surface of the ceramic layer,
A laminated coil component characterized by   The multilayer coil component according to claim 4, wherein a portion of the coil conductor adjacent to the extraction electrode portion is inclined with respect to the multilayer surface of the ceramic layer.   6. The laminated coil component according to claim 4, wherein each of the coil conductors has a length corresponding to a half turn. The multilayer coil component according to any one of claims 4 to 6, wherein the external electrode is formed on an end surface orthogonal to the coil axis direction of the sintered body unit.

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