JP2012142357A - Multilayer inductor and multilayer inductor manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multilayer inductor which can further improve DC superposition characteristics without causing an inductance value to drop.SOLUTION: A coil 12 is led out at one end to one side face of a laminate 3 and led out at other end to a side face opposite to the one side face of the laminate 3, and includes a first region 12a where N bodies (N=natural number equal to or greater than 2) of conductor 11 overlap, as viewed in the axial direction, and a second region 12b where N-1 bodies of conductor 11 overlap. The laminate 3 includes, as an insulator 13, a plurality of first insulators 15 made of magnetic material and a plurality of second insulators 17 disposed so as to be sandwiched between the plurality of first insulators 15 and made of non-magnetic material, the insulators being laminated one on another. The second insulator 17 is disposed over the whole of faces intersecting in the axial direction of the laminate 3 so as to cross the coil 12, in which the thickness of a portion 17a corresponding to the first region 12a is greater than that of a portion 17b corresponding to the second region 12b.

Description

  The present invention relates to a multilayer inductor and a method for manufacturing the multilayer inductor.

  2. Description of the Related Art A multilayer inductor is known that includes a multilayer body formed by laminating a conductor that forms a spiral coil and an insulator (see, for example, Patent Document 1). In the multilayer inductor described in Patent Document 1, an insulator made of a non-magnetic material is provided along a surface that intersects the axial center direction of the coil in the multilayer body so as to cross the coil. A magnetic gap is formed by an insulator made of a non-magnetic material, and the direct current superimposition characteristics are improved.

JP 2004-014549 A

  In the multilayer inductor described in Patent Document 1, the insulator made of a nonmagnetic material is not provided over the entire surface of the laminate that intersects the axial direction of the coil, and the insulator made of the nonmagnetic material is interrupted. An area exists. For this reason, the magnetic flux bypasses the insulator made of a non-magnetic material and passes through the region where the insulator made of the non-magnetic material in the laminated body is interrupted, so that the magnetic flux is concentrated in the region and magnetic saturation is likely to occur. Become. As a result, the multilayer inductor described in Patent Document 1 may not be able to sufficiently improve the DC superposition characteristics.

  An object of the present invention is to provide a multilayer inductor capable of further improving the direct current superposition characteristics without lowering the inductance value.

  As a result of investigations by the present inventors, in order to improve the DC superposition characteristics, it is conceivable to adopt a configuration in which an insulator made of a non-magnetic material is provided over the entire surface of the laminate that intersects the axial direction of the coil. However, when the said structure was employ | adopted, it became clear that it had the following problems.

  In a multilayer inductor, generally, a coil formed by connecting a conductor has one end pulled out to one side surface of the multilayer body and the other end pulled out to a side surface facing the one side surface of the multilayer body. . For this reason, the coil has a first region where conductors of N bodies (N is a natural number of 2 or more) overlap each other and a second region where conductors of N-1 bodies overlap each other in the axial direction of the coil. , Will be included. Since the first region of the coil has more conductors than the second region of the coil, the magnetic flux density in the first region of the coil is higher than the magnetic flux density in the second region of the coil.

  In a configuration in which an insulator made of a non-magnetic material is provided over the entire surface of the laminated body that intersects the axial center direction of the coil, the thickness of the insulator made of the non-magnetic material takes into consideration the magnetic flux density in the first region of the coil. If the thickness is set so that magnetic saturation is unlikely to occur in the first region of the coil, the magnetic flux density in the second region of the coil may be lower than the magnetic flux density in the first region of the coil. There is. Considering the magnetic flux density in the second region of the coil in consideration of the magnetic flux density in the second region of the coil, the magnetic flux density in the first region of the coil is Since it is higher than the magnetic flux density in the second region of the coil, magnetic saturation is likely to occur in the first region of the coil, and the direct current superimposition characteristics may not be sufficiently improved.

  In order to solve these problems, the present invention provides a multilayer inductor including a multilayer body in which a conductor that forms a spiral coil and an insulator are laminated, and the conductor is made of an insulator. The coils are connected to each other so that the lamination direction is formed as the axial direction, and the coil has one end drawn out to one side surface of the laminated body and the other end drawn out to the side surface facing one side surface of the laminated body, When viewed in the axial direction, the laminate includes a first region in which N (N is a natural number of 2 or more) conductors overlap and a second region in which N-1 conductors overlap. As the insulator, a plurality of first insulators made of a magnetic material and at least one second insulator made of a nonmagnetic material are stacked so as to be sandwiched between the plurality of first insulators. The at least one second insulator crosses the coil Provided over the entire surface intersecting the axis direction of Sotai, the thickness of a portion corresponding to the first region of the coil is equal to or greater than the thickness of a portion corresponding to the second region of the coil.

  In the multilayer inductor according to the present invention, at least one second insulator made of a nonmagnetic material is provided over the entire surface of the multilayer body that intersects the axial center direction of the coil so as to cross the coil, and the first region of the coil Is thicker than the portion corresponding to the second region of the coil. For this reason, the direct current superimposition characteristic can be further improved without reducing the inductance value.

  The present invention relates to a multilayer inductor in which insulator layers and conductor patterns are alternately printed and laminated, a spiral coil pattern is formed in the laminate while connecting the ends of the conductor pattern, and the laminate is fired. A manufacturing method comprising: a step of printing a magnetic layer as an insulator layer; and a step of printing a nonmagnetic layer as an insulator layer, and the step of printing the nonmagnetic layer includes: Of the laminated body on the region side where N conductor patterns (N is a natural number of 2 or more) overlap in the stacking direction of the laminate and the region side where N-1 conductor patterns overlap in the stacking direction of the laminate. The number of times the nonmagnetic material layer is printed on the side of the region where the N conductor patterns overlap is printed across the entire surface of the laminate that crosses the coil pattern and intersects the axial direction of the coil pattern in the laminate. N-1 conductor pattern And characterized in that more than the number of times of printing a non-magnetic layer on the region side where the overlap.

  Also, the present invention provides a laminate in which insulator layers and conductor patterns are alternately printed and laminated, a spiral coil pattern is formed in the laminate while connecting the ends of the conductor pattern, and the laminate is fired. A method for manufacturing an inductor, comprising: a step of printing a magnetic layer as an insulator layer; and a step of printing a nonmagnetic layer as an insulator layer. The body layer is formed on the side where the N-type (N is a natural number of 2 or more) conductor pattern overlaps in the stacking direction of the stack and the side where the N-1 conductor pattern overlaps in the stacking direction of the stack. The thickness of the non-magnetic material layer printed on the side of the region where the N conductor patterns overlap, which is printed so as to cross the coil pattern in the middle of the lamination and to cover the entire surface of the laminated body that intersects the axial direction of the coil pattern N-1 conductor Turn characterized by being thicker than that prints the non-magnetic layer on the region side overlapping.

  According to these multilayer inductor manufacturing methods according to the present invention, the non-magnetic insulator is provided over the entire surface of the multilayer body that intersects the axial direction of the coil so as to cross the coil. A multilayer inductor in which the thickness of the portion corresponding to the region is thicker than the thickness of the portion corresponding to the second region of the coil can be obtained.

  ADVANTAGE OF THE INVENTION According to this invention, the laminated inductor which can aim at the further improvement of a direct current | flow superimposition characteristic, without reducing an inductance value can be provided.

It is a perspective view which shows the multilayer inductor which concerns on this embodiment. It is a figure for demonstrating the cross-sectional structure of a laminated body. It is a figure for demonstrating the manufacturing method of the multilayer inductor which concerns on this embodiment. It is a figure for demonstrating the manufacturing method of the multilayer inductor which concerns on this embodiment. It is a figure for demonstrating the manufacturing method of the multilayer inductor which concerns on this embodiment. It is a figure for demonstrating the manufacturing method of the multilayer inductor which concerns on this embodiment. It is a figure for demonstrating the manufacturing method of the multilayer inductor which concerns on this embodiment. It is a figure for demonstrating the manufacturing method of the multilayer inductor which concerns on this embodiment. It is a figure for demonstrating the manufacturing method of the multilayer inductor which concerns on this embodiment. It is a figure for demonstrating the manufacturing method of the multilayer inductor which concerns on this embodiment. It is a figure for demonstrating the manufacturing method of the multilayer inductor which concerns on this embodiment. It is a figure for demonstrating the manufacturing method of the multilayer inductor which concerns on this embodiment. It is a figure for demonstrating the manufacturing method of the multilayer inductor which concerns on this embodiment. It is a figure for demonstrating the manufacturing method of the multilayer inductor which concerns on this embodiment. It is a figure for demonstrating the manufacturing method of the multilayer inductor which concerns on this embodiment. It is a figure for demonstrating the manufacturing method of the multilayer inductor which concerns on this embodiment. It is a figure for demonstrating the manufacturing method of the multilayer inductor which concerns on this embodiment. It is a figure for demonstrating the manufacturing method of the multilayer inductor which concerns on this embodiment. It is a figure for demonstrating the modification of the manufacturing method of the multilayer inductor which concerns on this embodiment.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description, the same reference numerals are used for the same elements or elements having the same function, and redundant description is omitted.

  FIG. 1 is a perspective view showing the multilayer inductor according to the present embodiment. FIG. 2 is a diagram for explaining a cross-sectional configuration of the laminated body.

  The multilayer inductor 1 includes a substantially rectangular parallelepiped multilayer body 3 and a pair of terminal electrodes 5 disposed at both ends of the multilayer body 3 in the longitudinal direction (X direction in the drawing). The laminate 3 is formed by a manufacturing method (print lamination method) described later, and is a laminate in which a plurality of conductors 11 and insulators 13 are laminated. The laminated body 3 has a pair of side surfaces 3a and 3b that face each other in the longitudinal direction. The multilayer inductor 1 has a spiral coil 12 formed of a plurality of conductors 11 in the multilayer body 3.

  The plurality of conductors 11 are connected to each other such that the coil 12 is formed with the lamination direction (Y direction in the figure) of the insulator 13 as the axial direction. Of the plurality of conductors 11, the conductor 11 positioned at one end of the coil 12 has its end drawn out to the side surface 3 a and exposed. Of the plurality of conductors 11, the conductor 11 positioned at the other end of the coil 12 has its end drawn to the side surface 3 a and exposed. Thereby, one end of the coil 12 is drawn out to the side surface 3 a of the multilayer body 3, and the other end of the coil 12 is drawn out to the side surface 3 b of the multilayer body 3. Each conductor is made of a sintered body of metal (for example, Ag, Pd, or an alloy thereof).

  Since the end of the coil 12 is drawn out to the pair of side surfaces 3a and 3b opposite to each other, as shown in FIG. 2, the coil 12 is viewed in the axial direction of the coil 12, and the N body (N is 2 The first region 12a in which the conductors 11 of the above natural numbers, which are “three bodies” in the present embodiment, overlap, and the N-1 body (“two bodies” in the present embodiment) of the conductors 11 are formed. And an overlapping second region 12b.

  Each terminal electrode 5 is formed so as to cover all the portions exposed on the side surfaces 3 a and 3 b of the conductor 11, and the conductor 11 is physically and electrically connected to the terminal electrode 5. As a result, the coil 12 is connected to each terminal electrode 5 at both ends thereof. Each terminal electrode 5 is formed by applying and baking a conductive paste containing a conductive metal powder (for example, Ag powder, Ni powder, or Cu powder) on a corresponding portion of the outer surface of the laminate 3. . If necessary, a plating layer may be formed on the terminal electrode 5.

  The plurality of insulators 13 includes a plurality of first insulators 15 (in this embodiment, “2”) made of a magnetic material and at least one (in this embodiment, “1”) first insulators 15 made of a non-magnetic material. Two insulators 17. The laminate 3 is formed by laminating the first insulator 15 and the second insulator 17 so that the second insulator 17 is disposed between the first insulators 15. The first insulator 15 is made of ferrite (for example, Ni—Cu—Zn ferrite, Ni—Cu—Zn—Mg ferrite, Cu—Zn ferrite, or Ni—Cu ferrite). The second insulator 17 is made of ferrite (for example, Cu—Zn-based ferrite).

  The second insulator 17 is provided over the entire surface of the stacked body 3 that intersects the axial direction of the coil 12 so as to cross the coil 12. The second insulator 17 includes a portion 17 a corresponding to the first region 12 a of the coil 12 and a portion 17 b corresponding to the second region 12 b of the coil 12. The boundary between the portion 17 a corresponding to the first region 12 a of the second insulator 17 and the portion 17 b corresponding to the second region 12 b of the coil 12 is located at the approximate center in the width direction of the multilayer body 3. The thickness of the portion 17 a corresponding to the first region 12 a of the second insulator 17 is set to be thicker than the thickness of the portion 17 b corresponding to the second region 12 b of the coil 12.

  Next, a method for manufacturing the multilayer inductor 1 will be described with reference to FIGS. The multilayer inductor 1 is manufactured by a printing lamination method. 3 to 18 are views for explaining a method of manufacturing the multilayer inductor according to the present embodiment. In FIGS. 3 to 18, for the sake of explanation, only the portion corresponding to one laminate 3 is shown for the intermediate obtained by the printing laminate method.

  First, magnetic powder (for example, Ni—Cu—Zn-based ferrite powder), a binder, a solvent, and the like are kneaded to generate a magnetic paste that is a raw material for the first insulator 15. Nonmagnetic powder (for example, Cu—Zn-based ferrite powder), a binder, a solvent, and the like are kneaded to generate a nonmagnetic paste that is a raw material for the second insulator 17. The conductive metal powder, binder, solvent, and the like described above are kneaded to generate a conductive paste that is a raw material for the conductor 11.

  Next, using the obtained magnetic paste, non-magnetic paste, and conductive paste, an intermediate body is formed by laminating them by a printing lamination method. In this printing process, a green layer having a desired thickness is formed by printing a magnetic paste and a non-magnetic paste a plurality of times. The thickness of the paste film formed by one printing is, for example, about 3 to 10 μm.

  The magnetic paste is printed in a sheet form to form the magnetic green layer A11 (see FIG. 3). A magnetic paste green layer A12 is formed by printing a magnetic paste multiple times (for example, twice) so as to cover part of the surface of the magnetic green layer A11 (substantially the left half in the figure) (see FIG. 4). ). A conductive paste is printed on the surface of the magnetic green layer A11 to form a conductor pattern C11 corresponding to approximately 1/4 turn of the coil 12 (see FIG. 5). At this time, the conductive paste is printed so that one end of the conductor pattern C11 is drawn out to the edges of the magnetic green layers A11 and A12. A portion of the conductor pattern C11 is exposed on the surface, and a magnetic paste is printed a plurality of times (for example, four times) so as to cover a portion of the surface of the magnetic green layer A11 (substantially right half in the figure). Then, the magnetic green layer A13 is formed (see FIG. 6).

  A conductive paste C is printed on the surfaces of the magnetic green layers A12 and A13 so that the other end and the other end of the conductor pattern C11 overlap each other, thereby forming a conductor pattern C12 corresponding to approximately 1/2 turn of the coil 12 (see FIG. 7). ). A portion of the conductor pattern C12 is exposed on the surface, and a magnetic paste is printed a plurality of times (for example, four times) so as to cover the surface of the magnetic green layer A12 to form the magnetic green layer A14 (FIG. 8). Conductive paste is printed on the surface of the magnetic green layers A13 and A14 so that the other end and the other end of the conductor pattern C12 overlap each other, thereby forming a conductor pattern C13 corresponding to approximately 1/2 turn of the coil 12 (see FIG. 9). ).

  A part of the conductor pattern C13 is exposed on the surface, and a magnetic paste is printed a plurality of times (for example, twice) so as to cover the surface of the magnetic green layer A13 to form the magnetic green layer A15 (FIG. 10). Here, the printing frequency of the magnetic paste is less than the printing count for forming the magnetic green layers A13 and A14, and the thickness of the magnetic green layer A15 is thinner than the thickness of the magnetic green layers A13 and A14. Specifically, the number of times of printing for forming the magnetic body green layer A15 is half of the number of times of printing for forming the magnetic body green layers A13 and A14, and the thickness of the magnetic body green layer A15 is equal to the thickness of the magnetic body green layer. It is approximately half the thickness of A13 and A14.

  A nonmagnetic paste is printed a plurality of times (for example, twice) so as to cover the surface of the magnetic green layer A15 to form a nonmagnetic green layer B11 (see FIG. 11). Here, the number of times of printing for forming the nonmagnetic green layer B11 is the same as the number of times of printing for forming the magnetic green layer A15. Therefore, the sum of the thickness of the magnetic green layer A15 and the thickness of the nonmagnetic green layer B11 is substantially the same as the thickness of the magnetic green layers A13 and A14.

  A conductive paste is printed on the surface of the magnetic green layer A14 and the nonmagnetic green layer B11 so that the other end and one end of the conductive pattern C13 overlap, and a conductive pattern C14 corresponding to approximately 1/2 turn of the coil 12 is formed. Form (see FIG. 12).

  A portion of the conductor pattern C14 is exposed on the surface, and a nonmagnetic paste is printed a plurality of times (for example, three times) so as to cover the surface of the magnetic green layer A14 and to be in contact with the nonmagnetic green layer B11. A nonmagnetic green layer B12 is formed (see FIG. 13). Here, the number of times of printing for forming the nonmagnetic green layer B12 is larger than the number of times of printing for forming the nonmagnetic green layer B11. Therefore, the nonmagnetic green layer B12 is thicker than the nonmagnetic green layer B11.

  A magnetic paste is printed so as to cover the surface of the nonmagnetic green layer B12 to form the magnetic green layer A16 (see FIG. 14). Here, the number of times of printing for forming the magnetic green layer A16 is one, and the sum of the number of times of printing for forming the nonmagnetic green layer B12 and the number of times of printing for forming the magnetic green layer A16 is The number of times of printing for forming the nonmagnetic green layer B11 and the number of times of printing for forming the magnetic green layer A15 is the same as the number of times of printing for forming the magnetic green layers A13 and A14. The same. Therefore, the sum of the thickness of the non-magnetic green layer B12 and the thickness of the magnetic green layer A16 is substantially the same as the thickness of the magnetic green layers A13 and A14.

  Since the number of printings for forming the nonmagnetic green layer B12 is larger than the number of printings for forming the nonmagnetic green layer B11, the thickness of the nonmagnetic green layer B12 is set to the nonmagnetic green layer B11. Thicker than the thickness. The nonmagnetic green layer B11 and the nonmagnetic green layer B12 are formed in contact with each other and are formed so as to cover the entire surface of the magnetic green layers A14 and A15, that is, the entire surface of the intermediate.

  A conductive paste is printed on the surface of the magnetic green layer A16 and the nonmagnetic green layer B11 so that the other end and the other end of the conductive pattern C14 overlap, and a conductive pattern C15 corresponding to approximately 1/2 turn of the coil 12 is formed. Form (see FIG. 15). A part of the conductor pattern C15 is exposed on the surface, and a magnetic paste is printed a plurality of times (for example, four times) so as to cover the surface of the nonmagnetic green layer B11 to form the magnetic green layer A17 ( FIG. 16).

  Conductive paste is printed on the surfaces of the magnetic green layer A16 and the magnetic green layer A17 so that the other end and one end of the conductive pattern C15 overlap each other, thereby forming a conductive pattern C16 corresponding to approximately 1/4 turn of the coil 12. (See FIG. 17). At this time, the conductive paste is printed so that the other end of the conductor pattern C16 is drawn to the edge of the magnetic green layers A16 and A17 (the edge opposite to the edge from which the conductor pattern C11 is drawn). A magnetic paste is printed so as to cover the entire surface of the intermediate, thereby forming a magnetic green layer A18 (see FIG. 18).

  Next, the intermediate obtained by the printing lamination method is cut into chips. Each green chip is subjected to heat treatment under predetermined conditions (for example, 200 to 600 ° C. and 3 to 6 hours) to perform binder removal, and further, predetermined conditions (for example, 800 to 900 ° C. and 3-7 hours). By this firing, the magnetic green layers A11 to A15 and the magnetic green layers A16 to A18 respectively become the first insulator 15, the nonmagnetic green layers B11 and B12 become the second insulator 17, and the conductor patterns C11 to C16. Becomes the conductor 11 (coil 12). That is, the laminate 3 is obtained. The laminate 3 has, for example, a length in the longitudinal direction after firing of 1.6 to 3.2 mm, a width of 0.8 to 2.5 mm, and a height of 0.8 to 1.25 mm. Each of the conductor patterns C11 to C16 has, for example, a width after firing of 100 to 400 μm and a thickness of 15 to 50 μm.

  Next, a conductive paste is applied so as to cover both side surfaces 3a and 3b of the laminate 3, and heat treatment is performed under predetermined conditions (for example, 600 to 800 ° C. and 0.5 to 3 hours). The terminal electrode 5 is formed by baking the functional paste on the laminate 3. Then, a plating layer is formed by performing electroplating treatment such as Ni plating and Sn plating so as to cover the terminal electrode 5. As the conductive paste, for example, a mixture of the above-described conductive metal powder with glass frit and an organic vehicle can be used.

  Through these processes, the multilayer inductor 1 is obtained.

  As described above, in the present embodiment, the second insulator 17 made of a nonmagnetic material is provided over the entire surface of the multilayer body 3 that intersects the axial direction of the coil 12 so as to cross the coil 12. For this reason, in the multilayer inductor 1, there is no region where the insulator made of a nonmagnetic material is interrupted on the surface of the multilayer body 3 that intersects the axial center direction of the coil 12. Therefore, in the multilayer inductor 1, magnetic saturation hardly occurs and the direct current superimposition characteristic can be improved.

  In the multilayer inductor 1, one end of the coil 12 is pulled out to the side surface 3 a of the multilayer body 3, and the other end is pulled out to the side surface 3 b of the multilayer body 3. For this reason, the coil 12 has a first region 12a in which N conductors 11 (N = 3 in the present embodiment) overlap with each other when viewed in the axial direction of the coil 12, and an N−1 conductor 11 And the overlapping second region 12b. Since the first region 12a of the coil 12 has a larger number of conductors 11 than the second region 12b of the coil 12, the magnetic flux density in the first region 12a of the coil 12 is the magnetic flux density in the second region 12b of the coil 12. Higher than.

  In the present embodiment, the difference in magnetic flux density between the first region 12a and the second region 12b of the coil 12 is taken into consideration, and the second insulator 17 has a thickness corresponding to the first region 12a of the coil 12. The coil 12 is thicker than the portion corresponding to the second region 12b. Since the magnetic flux density in the first region 12a of the coil 12 is higher than the magnetic flux density in the second region 12b of the coil 12, magnetic saturation occurs in the first region 12a of the coil 12 as compared with the second region 12b of the coil 12. Although easy, as described above, in the second insulator 17, the thickness of the portion corresponding to the first region 12a is thicker than the thickness of the portion corresponding to the second region 12b. Saturation is unlikely to occur, and there is no problem in improving the DC superimposition characteristics.

  In the present embodiment, in the second insulator 17, the thickness of the portion corresponding to the second region 12 b of the coil 12 is thinner than the thickness of the portion corresponding to the first region 12 a of the coil 12. For this reason, in the 2nd area | region 12b whose magnetic flux density is low compared with the 1st area | region 12a of the coil 12, the 2nd insulator 17 does not become trouble, and the fall of an inductance value is suppressed.

  As a result, in the multilayer inductor 1, the direct current superimposition characteristics can be further improved without reducing the inductance value. By further improving the direct current superposition characteristics, the multilayer inductor 1 can also improve the rated current.

  In the manufacturing method according to this embodiment, the nonmagnetic green layer B11 is printed and formed on the side where the two conductor patterns C12 to C14 overlap in the stacking direction of the intermediate, and the nonmagnetic green layer B12 is formed of the intermediate. The three conductor patterns C11 to C16 are printed in the overlapping direction in the stacking direction, and the nonmagnetic green layer B11 and the nonmagnetic green layer B12 cross the coil pattern in the middle of the intermediate stacking and intermediate It is printed and formed over the entire surface of the body that intersects the axial direction of the coil pattern. Then, the number of times of printing for forming the nonmagnetic green layer B12 is set larger than the number of times of printing for forming the nonmagnetic green layer B11, and the thickness of the nonmagnetic green layer B12 is set to the nonmagnetic green layer. It is thicker than the thickness of B11. Thereby, in the manufacturing method described above, the multilayer inductor 1 is obtained in which the thickness of the second insulator 17 is greater than the thickness of the portion corresponding to the second region 12b. Can do.

  The preferred embodiments of the present invention have been described above. However, the present invention is not necessarily limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention.

  In the embodiment described above, the thickness of the nonmagnetic green layer B12 is set by setting the number of times of printing for forming the nonmagnetic green layer B12 to be larger than the number of times of printing for forming the nonmagnetic green layer B11. Is thicker than the nonmagnetic green layer B11, but is not limited thereto. For example, as shown in FIG. 19, a plurality of screen plates having different plate thicknesses are used as the screen plates used for printing the nonmagnetic green layers B11 and B12, and a non-magnetic screen plate having a thin thickness is used. The green body layer B11 may be formed by a single printing, and the non-magnetic green layer B12 may be formed by a single printing process using a thick screen plate.

  In this case, since the plate thickness of the screen plate used is different, the thickness for printing the nonmagnetic green layer B12 is larger than the thickness for printing the nonmagnetic green layer B12. In the modification shown in FIG. 19 as well, the multilayer inductor 1 in which the thickness of the second insulator 17 is larger than the thickness of the portion corresponding to the first region 12b is greater than the thickness of the portion corresponding to the second region 12b. Obtainable. The steps shown in FIG. 19 correspond to the steps shown in FIGS.

  The number of the second insulators 17 is not limited to one and may be two or more. When the number of the second insulators 17 is two or more, the thickness of the portion corresponding to the first region 12a in the at least one second insulator 17 is larger than the thickness of the portion corresponding to the second region 12b. That's fine.

  The number of turns of the coil 12, that is, the number of conductors 11 overlapping in the axial direction of the coil 12 is not limited to the above-described value.

  DESCRIPTION OF SYMBOLS 1 ... Multilayer inductor, 3 ... Laminated body, 3a, 3b ... Side surface, 11 ... Conductor, 12 ... Coil, 12a ... 1st area | region, 12b ... 2nd area | region, 13 ... Insulator, 15 ... 1st insulator, 17 ... Second insulator, 17a: portion corresponding to the first region, 17b: portion corresponding to the second region, A11 to A18 ... magnetic body green layer, B11, B12 ... nonmagnetic body green layer, C11 to C16 ... conductor pattern .

Claims (3)

A laminated inductor comprising a laminate in which a conductor and an insulator forming a spiral coil are laminated,
The conductors are connected to each other so that the coil is formed with the lamination direction of the insulators as the axial direction,
One end of the coil is drawn out to one side surface of the laminated body, and the other end is drawn out to a side surface opposite to the one side surface of the laminated body. A first region where the conductors of 2 or more natural numbers overlap, and a second region where the N-1 conductors overlap,
The laminated body includes, as the insulator, a plurality of first insulators made of a magnetic material, and at least one second insulator made of a non-magnetic material and disposed between the plurality of first insulators. And are laminated,
The at least one second insulator is provided over the entire surface of the laminated body that intersects the axial direction so as to cross the coil, and a thickness of a portion corresponding to the first region of the coil is the coil. A multilayer inductor characterized by being thicker than a portion corresponding to the second region. A method of manufacturing a multilayer inductor, wherein insulating layers and conductor patterns are alternately printed and laminated, a spiral coil pattern is formed in the laminate while connecting ends of the conductor patterns, and the laminate is fired Because
A step of printing a magnetic layer as the insulator layer, and a step of printing a non-magnetic layer as the insulator layer,
In the step of printing the non-magnetic material layer, the non-magnetic material layer is laminated in the stacking direction of the multilayer body in the stacking direction of the multilayer body, and the N-side (N is a natural number of 2 or more) region where the conductor patterns overlap. In the area where the conductor patterns of the N-1 body overlap, printing is performed so as to cross the coil pattern in the middle of the lamination of the laminate and to cover the entire surface of the laminate that intersects the axial direction of the coil pattern. And
The number of times of printing the nonmagnetic layer on the region side where the N conductor pattern overlaps is made larger than the number of times of printing the nonmagnetic layer on the region side where the N-1 conductor pattern overlaps. A method for manufacturing a multilayer inductor, which is characterized. A method of manufacturing a multilayer inductor, wherein insulating layers and conductor patterns are alternately printed and laminated, a spiral coil pattern is formed in the laminate while connecting ends of the conductor patterns, and the laminate is fired Because
A step of printing a magnetic layer as the insulator layer, and a step of printing a non-magnetic layer as the insulator layer,
In the step of printing the non-magnetic material layer, the non-magnetic material layer is laminated in the stacking direction of the multilayer body in the stacking direction of the multilayer body, and the N-side (N is a natural number of 2 or more) region where the conductor patterns overlap. In the area where the conductor patterns of the N-1 body overlap, printing is performed so as to cross the coil pattern in the middle of the lamination of the laminate and to cover the entire surface of the laminate that intersects the axial direction of the coil pattern. And
The thickness of printing the nonmagnetic material layer on the region side where the N conductor pattern overlaps is made thicker than the thickness of printing the nonmagnetic material layer on the region side where the N-1 conductor pattern overlaps. A method for manufacturing a multilayer inductor, which is characterized.

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