Method of manufacturing multilayer inductor

Abstract

To provide a method of manufacturing a multilayer inductor, with which DC resistance is further reduced.SOLUTION: A method of manufacturing a multilayer inductor according to the present disclosure is a method of manufacturing a multilayer inductor that is obtained by stacking layers which each include a coil conductor CD and a magnetic member ML in contact with an outer peripheral edge of the coil conductor CD. The method includes: a magnetic pattern formation step of forming a magnetic paste MP containing magnetic particles and a resin in a magnetic area MA located outside a conductor area CA where the coil conductor is disposed; a magnetic paste drying step of drying the magnetic paste MP to configure the magnetic member ML; a conductor pattern formation step of printing a conductive paste CP containing metal particles and a resin, higher than the height of the magnetic member ML at a position away from the magnetic area MA inside the conductor area CA; a conductor paste drying step of drying the conductor paste CP to configure the coil conductor CD; and a conductor pressing step of pressing at least the coil conductor CD to bring the coil conductor CD into contact with the magnetic member ML.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a method for manufacturing a laminated inductor. [Background technology]

[0002] Patent Document 1 discloses a laminated inductor having a coil arranged within a laminate and in which a plurality of conductor patterns are electrically connected to one another, in which the conductor patterns have a peripheral side surface, which is an uneven surface with concave and convex portions arranged alternately along the lamination direction, and the laminate is inserted into the concave portions of the peripheral side surface. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2009-117664 Summary of the Invention [Problem to be solved by the invention]

[0004] The inventors of the present application have found that the laminated inductor described in Patent Document 1, in which the laminate is embedded in the recessed portion on the peripheral side surface of the conductor pattern, has a relatively high DC resistance.

[0005] In view of the above, an object of the present disclosure is to provide a method for manufacturing a laminated inductor that further reduces DC resistance. [Means for solving the problem]

[0006] The method for manufacturing a laminated inductor according to the present disclosure includes: A method for manufacturing a laminated inductor in which a layer including a coil conductor and a magnetic member in contact with an outer periphery of the coil conductor is laminated, the method comprising: a magnetic pattern forming step of printing a magnetic paste containing magnetic particles and a resin on a magnetic region located outside a conductor region in which the coil conductor is disposed; a magnetic paste drying step of drying the magnetic paste to form the magnetic member; a conductive pattern forming process of printing a conductive paste containing metal particles and a resin at a position inside the conductive region and spaced apart from the magnetic region, to a height higher than the height of the magnetic member; a conductor paste drying step of drying the conductive paste to form the coil conductor; and a conductor pressing step of pressing at least the coil conductor to bring the coil conductor into contact with the magnetic member. [Effects of the Invention]

[0007] According to the method for manufacturing a laminated inductor of the present disclosure, a laminated inductor with reduced DC resistance can be provided. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view of a laminated inductor according to the present disclosure. [Figure 2] FIG. 2 is an exploded perspective view of the laminated inductor of the present disclosure. [Figure 3] FIG. 3 shows a manufacturing flow of the method for manufacturing the laminated inductor of the present disclosure. [Figure 4] FIG. 4 is an explanatory diagram illustrating the manufacturing process of the laminated inductor of the present disclosure. [Figure 5] FIG. 5 is an explanatory diagram illustrating the manufacturing process of the laminated inductor of the present disclosure. [Figure 6] FIG. 6 is an explanatory diagram illustrating the manufacturing process of the laminated inductor of the present disclosure. [Figure 7] FIG. 7 is an explanatory diagram illustrating the manufacturing process of the laminated inductor of the present disclosure. [Figure 8] FIG. 8 is an explanatory diagram illustrating the manufacturing process of the laminated inductor of the present disclosure. [Figure 9] FIG. 9 is an explanatory diagram illustrating the manufacturing process of the laminated inductor of the present disclosure. [Figure 10] FIG. 10 is an explanatory diagram illustrating the manufacturing process of the laminated inductor of the present disclosure. [Figure 11] FIG. 11 is a cross-sectional view of a conventional multilayer inductor. [Figure 12] FIG. 12 is a graph showing the measurement results of the DC resistance value. DETAILED DESCRIPTION OF THE INVENTION

[0009] The laminated inductor and the method for manufacturing the laminated inductor according to the present disclosure will be described below. Note that the present disclosure is not limited to the following configurations and may be modified as appropriate without departing from the spirit of the present disclosure. Furthermore, a combination of multiple individual preferred configurations described below also constitutes the present disclosure.

[0010] The laminated inductor of the present disclosure is used in, for example, a DC-DC converter, and is particularly suitable for mounting between substrates or for being built into a substrate. The laminated inductor of the present disclosure can also be used for purposes other than DC-DC converters.

[0011] In this specification, terms indicating the relationship between elements (e.g., "parallel," "orthogonal," etc.) and terms indicating the shape of elements do not only mean the strict literal form, but also mean a range of substantial equivalence, for example, a range including a difference of about a few percent. Note that in this specification, the direction in which the magnetic layers and coil conductors that make up the element body are stacked is referred to as the "stacking direction."

[0012] The drawings shown below are schematic diagrams, and the dimensions, aspect ratio, scale, etc. may differ from those of the actual product.

[0013] <Laminated inductor of the present disclosure> The laminated inductor of the present disclosure will be described with reference to Figures 1 and 2. The laminated inductor of the present disclosure is formed by laminating element layers G1 to G8, each of which includes a coil conductor CD (see Figure 2) and a magnetic member ML (see Figure 2) in contact with the outer periphery of the coil conductor CD.

[0014] The element body 10 has, for example, a rectangular parallelepiped or approximately rectangular parallelepiped shape having six sides (see FIG. 1). The corners and ridges of the element body 10 may be rounded. A corner is a portion where three sides of the element body 10 intersect, and a ridge is a portion where two sides of the element body 10 intersect.

[0015] 1, the length direction, width direction, and height direction of the laminated inductor 1 and the element body 10 are shown as L direction, W direction, and T direction, respectively. The length direction L, width direction W, and height direction T are perpendicular to each other. The mounting surface of the laminated inductor 1 is, for example, a surface (LW surface) parallel to the length direction L and width direction W.

[0016] The element body 10 shown in Fig. 1 has a first main surface 11 and a second main surface 12 that face each other in the height direction T, a first end surface 13 and a second end surface 14 that are perpendicular to the height direction T and face each other in the length direction L, and a first side surface 15 and a second side surface 16 that face each other in the width direction W that is perpendicular to the length direction L and the height direction T. In the example shown in Fig. 1, the first main surface 11 of the element body 10 corresponds to the mounting surface (bottom surface) of the element body 10. It should be noted that the second main surface 12 may also be the mounting surface of the element body 10.

[0017] The element body 10 has a laminated structure in which a plurality of element body layers, on which magnetic members ML and coil conductors CD (see FIG. 2) are formed, are laminated in a lamination direction (for example, height direction T). In this embodiment, the element body 10 is constructed by laminating element body layers G1 to G8 as shown in FIG. 2. A coil is constructed by laminating a plurality of coil conductors CD. By constructing a coil by laminating coil conductors CD, it is possible to make it more compact than a wire-wound coil in which a conductor wire is wound. Note that the boundaries between layers in the laminated structure of the element body 10 disappear. Furthermore, each of the element body layers G1 to G8 may be constructed by laminating a plurality of identical patterns.

[0018] A coil formed by stacking multiple coil conductors CD is provided within element body 10. The example shown in Fig. 2 shows a form of one coil in which the coil conductors CD of element body layers G2, G4, and G6 are electrically connected via via conductors V of element body layers G3 and G5. The laminated inductor of this embodiment is not limited to the example shown in Fig. 2; for example, two or more coils may be provided overlapping in the stacking direction, and a coil array may be formed by arranging multiple coils side by side inside element body 10 in a direction intersecting the stacking direction (direction L in Fig. 1).

[0019] External electrodes E are provided on the mounting surface (first main surface 11) of the element body 10. In the example shown in Fig. 2, the external electrodes E include a first external electrode E1 electrically connected to one end of the coil, and a second external electrode E2 electrically connected to the other end of the coil. Two external electrodes are provided for one coil built into the element body, but if the number of coils is two, the number of external electrodes may be four.

[0020] Through-hole conductors TH are used to connect the coil (coil conductor CD) and the external electrodes E. That is, first through-hole conductors TH1 and second through-hole conductors TH2 are provided corresponding to the first external electrode E1 and second external electrode E2. The first through-hole conductors TH1 and second through-hole conductors TH2 extend in the direction of the mounting surface.

[0021] <Method for manufacturing a laminated inductor according to the present disclosure> The body layers G1 to G8 of the above-described laminated inductor are manufactured through a magnetic pattern forming process, a magnetic paste drying process, a magnetic member pressing process, a conductor pattern forming process, a conductor paste drying process, and a conductor pressing process, as shown in Fig. 3. Each process will be described in detail below.

[0022] -Magnetic pattern formation process- The magnetic pattern forming step is a step of applying a magnetic paste MP containing magnetic particles and a resin to a magnetic region MA located outside a conductor region CA where the coil conductor CD is arranged (see FIG. 4).

[0023] First, a magnetic paste MP for the magnetic member ML is prepared. As an example of a method for preparing the magnetic paste, a metal powder such as an Fe-Si alloy or an Fe-Si-Cr alloy with a volume-based cumulative 50% particle diameter (D50) of 2 μm or more and 20 μm or less is prepared. A binder such as cellulose or polyvinyl butyral (PVB) and a solvent such as a mixture of terpineol and butyl diglycol acetate (BCA) are added to the metal powder and kneaded to prepare the magnetic paste.

[0024] The magnetic paste MP of the present disclosure is a harder material than the conductor paste CP described below, and is a paste that is less likely to deform even in the magnetic member pressing process described below. Therefore, in the method for manufacturing a laminated inductor of the present disclosure, the magnetic pattern formation process using the magnetic paste MP is performed before the conductor paste CP.

[0025] After preparing the magnetic paste, the prepared magnetic paste MP is screen-printed to form a magnetic pattern on the base substrate SB. As an example, as shown in Figure 4, the magnetic paste MP is placed on a screen plate SM, and a squeegee SQ is pressed against the screen plate SM, and the squeegee SQ is moved parallel to the base substrate SB to form a pattern of the magnetic paste MP on the base substrate SB. The base substrate SB may be an aluminum plate or a stainless steel plate.

[0026] When forming a pattern of the magnetic paste MP on the base substrate SB, the magnetic paste MP may be printed by off-contact printing. In this specification, "off-contact printing" refers to screen printing performed while the screen plate SM and the base substrate SB are spaced apart. Screen printing performed by off-contact printing allows the paste to be applied relatively thickly (10 μm or more) by utilizing the elasticity of the screen plate SM. Furthermore, the gap between the screen plate SM and the base substrate SB can be adjusted, which allows for good releasability between the screen plate SM and the base substrate SB, enabling stable continuous printing. In an example shown in FIG. 4, screen printing is performed with the base substrate SB and the screen plate SM spaced a distance L1 apart. This off-contact printing allows the magnetic paste MP to be printed on the base substrate SB to a thickness corresponding to the distance L1 between the base substrate SB and the screen plate SM (see FIG. 5).

[0027] The magnetic pattern formation process may be performed by contact printing instead of off-contact printing. The term "contact printing" used in this specification refers to screen printing performed while the screen plate SM and the base substrate SB are in close contact with each other. Contact printing allows the magnetic paste MP to be printed on the base substrate SB in a thickness corresponding to the thickness of the screen plate SM.

[0028] -Magnetic paste drying process- After the magnetic paste formation step, the magnetic paste MP is dried to form the magnetic member ML. As an example, the magnetic paste is preferably dried using a drying device that dries the magnetic paste at a temperature set to 70°C or higher and 90°C or lower for 10 minutes or higher and 60 minutes or lower.

[0029] -Magnetic component pressing process (optional process)- As an optional step after the magnetic paste drying step, the magnetic member ML may be pressed (see FIG. 6). For example, the magnetic member ML is pressed using a pressurizing device PE at a pressing pressure of 1 t / cm. 2 More than 20t / cm 2The following pressure is applied to the magnetic member ML: By applying pressure to the magnetic member ML, the upper surface of the magnetic member ML can be flattened.

[0030] -Conductor pattern formation process- The conductive pattern forming step is a step of printing a conductive paste CP containing metal particles and resin at a position inside the conductive region CA and spaced apart from the magnetic region MA, to a height higher than the magnetic member ML.

[0031] First, the magnetic paste MP that constitutes the magnetic member ML is prepared. As the conductive paste, for example, a paste containing Ag as a conductive material is prepared.

[0032] After preparing the magnetic paste MP, the prepared conductive paste CP is screen-printed to form a conductive pattern on the base substrate SB. As an example, as shown in Figure 7, the conductive paste CP is placed on a screen plate SM, and a squeegee SQ is pressed against the screen plate SM, and the squeegee SQ is moved parallel to the base substrate SB to form a pattern of the conductive paste CP on the base substrate SB.

[0033] The conductive paste CP is formed so as to be spaced apart from the magnetic member ML. By spacing the conductive paste CP from the magnetic member ML, the conductive paste CP can be filled into the conductor region CA in the conductor pressing step described below, even for a pattern with a narrow line width such as the coil conductor CD of the element layers G2, G4, and G6 in FIG.

[0034] Here, the conductor paste CP is a softer material than the magnetic paste MP, and therefore is more easily deformed during the conductor pressing process described below. To further explain the ease with which the conductor paste CP is deformed, the conductor paste CP contains less binder resin for binding the metal particles (Ag particles) than the magnetic paste MP. Therefore, voids are more likely to form between the metal particles within the paste. Therefore, during the conductor pressing process described below, these voids collapse, making the conductor paste CP more easily deformed than the magnetic paste MP.

[0035] The conductive paste CP is printed higher than the height of the magnetic member ML. Specifically, the conductive paste CP is printed by off-contact printing, and is screen-printed with the base substrate SB and the screen plate SM spaced apart by a distance L2 (note that L2>L1), as shown in Fig. 7. By forming the conductive paste CP using this method, the height of the conductive paste CP can be made higher than the height of the magnetic member ML (see Fig. 8).

[0036] In a preferred conductor pattern forming step, the volume of the conductor paste CP formed by the conductor pattern forming step may correspond to the volume of the conductor region CA surrounded by the magnetic member ML. More specifically, although the conductor paste CP is formed so as to be spaced apart from the magnetic member ML, the height of the conductor paste CP is greater than the height of the magnetic member ML, and therefore, when the conductor pressing step described below is performed, the conductor region CA can be completely filled with the conductor paste CP.

[0037] Furthermore, in the conductive pattern forming process, the length L3 of the formed conductive paste CP may be 0.50 to 0.97 times the length L4 of the magnetic region (see FIG. 8 for an example). Even if the conductive paste CP is spaced apart from the magnetic member ML in this way, the conductive paste CP can be filled into the conductor region CA by performing the conductor pressing process described below. Note that the length L3 of the conductive paste CP and the length L4 of the magnetic region may be the average distance in each pattern. Furthermore, the term "spaced apart" in this specification does not mean that all sides of the magnetic member ML come into contact with the conductive paste CP; for example, the conductive paste CP may be allowed to come into contact with only a portion of the magnetic member ML.

[0038] -Conductor paste drying process- After the conductive paste forming step, the conductive paste CP is dried to form the coil conductor CD. For example, the conductive paste is preferably dried using a drying device that dries the conductive paste CP at a temperature of 70°C to 90°C for 10 minutes to 60 minutes.

[0039] -Conductor pressing process- After the conductor paste drying step, the coil conductor CD may be pressed (see FIG. 9). For example, the coil conductor CD is pressed using a pressurizing device PE at a pressing pressure of 1 t / cm. 2 More than 20t / cm 2 The following pressure is applied to the coil conductor CD: By applying pressure to the coil conductor CD, the upper surface of the coil conductor CD can be flattened.

[0040] 2, a laminated element body 10 is prepared. The laminated element body 10 then undergoes a drying process to reduce the moisture content within the element body 10, a degreasing process to remove the binders contained in the magnetic paste MP and conductor paste CP, a heat treatment process to sinter the coil conductor, a resin impregnation process to increase the strength of the element body, and an external electrode formation process to form external electrodes on the element body, thereby manufacturing the laminated inductor of the present disclosure.

[0041] As described above, in the method for manufacturing a laminated inductor according to the present disclosure, first, the magnetic member ML is formed using a magnetic paste that is a material harder than the conductive paste CP, then the coil conductor CD is formed using the conductive paste CP at a distance from the magnetic member ML, and then a conductor pressing step is performed in which the coil conductor CD is pressed and brought into contact with the magnetic member ML. Therefore, unlike the conventional laminated inductor shown in FIG. 11, the laminated inductor does not have an uneven surface in which concave and convex portions are alternately arranged in the lamination direction. Furthermore, as will be explained in the examples below, the laminated inductor according to the present disclosure can further reduce DC resistance compared to the conventional laminated inductor shown in FIG. 11. [Example]

[0042] The demonstration test for the laminated inductor of the present disclosure will be described in detail below. Specifically, the laminated inductors of Example 1 and Comparative Examples 1 to 3 below were manufactured.

[0043] Example 1 First, in the magnetic pattern forming process, a magnetic paste MP containing magnetic particles and a resin was formed in the magnetic region MA located outside the conductor region CA where the coil conductor CD was to be arranged. Next, in the magnetic paste drying process, the magnetic paste MP was dried to form the magnetic member ML. Next, in the conductor pattern forming process, a conductor paste CP containing metal particles and a resin was printed higher than the height of the magnetic member ML at a position inside the conductor region CA and spaced from the magnetic region MA. Next, in the conductor paste drying process, the conductor paste CP was dried to form the coil conductor CD. Then, in the conductor pressing process, pressure was applied to the coil conductor CD to bring the coil conductor CD into contact with the magnetic member ML.

[0044] Comparison Example 1 First, a conductor paste was formed in the conductor pattern forming process. The conductor paste was then dried to form a coil conductor. Next, a magnetic paste was printed in the magnetic paste forming process. The magnetic paste was then dried to form a magnetic member. The coil conductor and the magnetic member were then pressed together. Note that in Comparative Example 1, the number of layers was five.

[0045] Comparison Example 2 A multilayer inductor was manufactured through the same steps as in Comparative Example 1. Comparative Example 2 had the same height as Comparative Example 1, but had three layers.

[0046] Comparative Example 3 A multilayer inductor was manufactured through the same steps as in Comparative Example 1. Comparative Example 3 had the same height as Comparative Example 1, but had two layers.

[0047] Cross-sectional SEM observation was performed on the above Example 1 and Comparative Examples 1 to 3. In Comparative Examples 1 to 3, as shown in Fig. 11, the laminate ML' has entered the recessed portion on the peripheral side surface of the conductor pattern CD', but in Example 1, as shown in Fig. 10, the magnetic material has been reduced from entering the coil conductor.

[0048] Furthermore, the DC resistance was measured for Example 1 and Comparative Examples 1 to 3. The DC resistance was measured using a resistance meter (model number RM3545, manufactured by Hioki E.E. Corporation).

[0049] When the DC resistance was measured, the DC resistance of the multilayer inductors of Comparative Examples 1 to 3 was 16.7 mΩ, while the DC resistance of the multilayer inductor of Example 1 was 16.0 mΩ. Therefore, the DC resistance of the multilayer inductor manufactured by the manufacturing method of the multilayer inductor of the present disclosure was able to be reduced compared to conventional methods.

[0050] It should be noted that the embodiments disclosed herein are illustrative in all respects and are not intended to be limiting. Therefore, the technical scope of the present disclosure should not be interpreted solely by the above-described embodiments, but should be defined based on the claims. The technical scope of the present disclosure also includes all modifications within the scope and meaning equivalent to the claims.

[0051] The method for manufacturing a laminated inductor according to the present disclosure is as follows. <1> A method for manufacturing a laminated inductor in which a layer including a coil conductor and a magnetic member in contact with an outer periphery of the coil conductor is laminated, the method comprising: a magnetic pattern forming step of printing a magnetic paste containing magnetic particles and a resin on a magnetic region located outside a conductor region in which the coil conductor is disposed; a magnetic paste drying step of drying the magnetic paste to form the magnetic member; a conductive pattern forming process of printing a conductive paste containing metal particles and a resin at a position inside the conductive region and spaced apart from the magnetic region, to a height higher than the height of the magnetic member; a conductor paste drying step of drying the conductive paste to form the coil conductor; and a conductor pressing step of pressing the coil conductor to bring the coil conductor into contact with the magnetic member. <2> In the magnetic pattern forming step, the magnetic paste is printed by contact printing or off-contact printing. <1> 2. A method for manufacturing the laminated inductor according to claim 1 . <3> In the conductive pattern forming step, the conductive paste is applied by off-contact printing. <1> or <2> 2. A method for manufacturing the laminated inductor according to claim 1 . <4> In the magnetic pattern forming step, the magnetic paste is applied by off-contact printing, In the conductor pattern forming step, the conductive paste is applied by off-contact printing in which a screen plate is placed further away from a surface to be printed than in the magnetic pattern forming step. <1> ~ <3> 10. A method for manufacturing a laminated inductor according to any one of claims 1 to 9. <5> a magnetic member pressing step of pressing the magnetic member after the magnetic paste drying step and before the conductor pattern forming step; <1> ~ <4> 10. A method for manufacturing a laminated inductor according to any one of claims 1 to 9. <6> a volume of the conductor pattern formed in the conductor pattern forming step corresponds to a volume of the conductor region surrounded by the magnetic member; <1> ~ <5> 10. A method for manufacturing a laminated inductor according to any one of claims 1 to 9. <7> In the conductive pattern forming step, the length of the formed conductive paste is 0.5 to 0.97 times the length of the magnetic region. <1> ~ <6> 10. A method for manufacturing a laminated inductor according to any one of claims 1 to 9. <8> The pressure in the conductor pressing step is 1 t / cm 2 More than 20t / cm 2 Below is the <1> ~ <7> 10. A method for manufacturing a laminated inductor according to any one of claims 1 to 9. [Industrial Applicability]

[0052] The method for manufacturing a laminated inductor according to the present disclosure can be suitably used as a method for manufacturing a laminated inductor that further reduces DC resistance. [Explanation of symbols]

[0053] 1. Multilayer inductor 10 Base 11 First main surface 12 Second main surface 13 First end surface 14 Second end face 15 First aspect 16 Second aspect CA Conductor Area CD Coil Conductor CD' conductor pattern CP Conductive Paste E External electrode E1 1st external electrode E2 2nd external electrode G1~G8 base layer L1,L2 distance MA magnetic region ML Magnetic Materials ML' laminate MP Magnetic Paste PE pressure device SB base board SM Screen Edition SQ Squeegee TH through-hole conductor TH1 First through-hole conductor TH2 Second through-hole conductor V via conductor

Claims

1. A method for manufacturing a laminated inductor in which a layer including a coil conductor and a magnetic member in contact with an outer periphery of the coil conductor is laminated, the method comprising: a magnetic pattern forming step of printing a magnetic paste containing magnetic particles and a resin on a magnetic region located outside a conductor region in which the coil conductor is disposed; a magnetic paste drying step of drying the magnetic paste to form the magnetic member; a conductive pattern forming process of printing a conductive paste containing metal particles and a resin at a position inside the conductive region and spaced apart from the magnetic region, to a height higher than the height of the magnetic member; a conductor paste drying step of drying the conductive paste to form the coil conductor; and a conductor pressing step of applying pressure to the coil conductor to bring the coil conductor into contact with the magnetic member.

2. The method for manufacturing a laminated inductor according to claim 1 , wherein in the magnetic pattern forming step, the magnetic paste is applied by contact printing or off-contact printing.

3. The method for manufacturing a laminated inductor according to claim 1 , wherein in the conductive pattern forming step, the conductive paste is applied by off-contact printing.

4. In the magnetic pattern forming step, the magnetic paste is applied by off-contact printing, 2. The method for manufacturing a laminated inductor according to claim 1, wherein in the conductor pattern forming step, the conductive paste is applied by off-contact printing in which a screen is placed further away from the surface to be printed than in the magnetic pattern forming step.

5. 2. The method for manufacturing a laminated inductor according to claim 1, further comprising a magnetic member pressing step of pressing the magnetic member after the magnetic paste drying step and before the conductor pattern forming step.

6. The method for manufacturing a laminated inductor according to claim 1 , wherein a volume of the conductor pattern formed in the conductor pattern forming step corresponds to a volume of the conductor region surrounded by the magnetic member.

7. 2. The method for manufacturing a laminated inductor according to claim 1, wherein in the conductive pattern forming step, the length of the formed conductive paste is 0.50 to 0.97 times the length of the magnetic region.

8. The pressing pressure in the conductor pressing step is 1 t / cm ２ More than 20t / cm ２ The method for manufacturing a laminated inductor according to claim 1, wherein:

Images