Inductor and method of manufacturing same

Patent metadata

Field	Value
Publication number	US-2016343489-A1
Application number	US-201615150532-A
Country	US
Kind code	A1
Filing date	May 10, 2016
Priority date	May 19, 2015
Publication date	Nov 24, 2016
Grant date	—

Abstract

An inductor includes a coil substrate, an encapsulation material containing a magnetic material and selectively covering the coil substrate, and first and second external electrodes formed on the exterior of the encapsulation material. The coil substrate includes a laminate of stacked structures each including a conductive track and first and second connection parts on opposite sides of the conductive track in a single wiring layer. The conductive tracks are connected in series to form a helical coil. The first connection parts are connected by a first via to form a first electrode terminal connected to a first end of the helical coil. The second connection parts are connected by a second via to form a second electrode terminal connected to a second end of the helical coil. The first and second external electrodes are connected to the first and second electrode terminals, respectively.

First claim

What is claimed is:

1 . An inductor, comprising:
a coil substrate including a laminate of a plurality of stacked structures, each of the stacked structures including
a conductive track; and
a first connection part and a second connection part on opposite sides of the conductive track, the conductive track and the first and second connection parts being formed in a single wiring layer,
wherein the conductive tracks of the stacked structures are connected in series to form a helical coil, the first connection parts of the stacked structures are connected by a first via to form a first electrode terminal connected to a first end of the helical coil, and the second connection parts of the stacked structures are connected by a second via to form a second electrode terminal connected to a second end of the helical coil; an encapsulation material containing a magnetic material, the encapsulation material selectively covering the coil substrate; and a first external electrode and a second external electrode formed on an exterior of the encapsulation material, the first external electrode being connected to the first electrode terminal, the second external electrode being connected to the second electrode terminal.

2 . The inductor as claimed in claim 1 , wherein
the coil substrate includes first and second end surfaces opposite to each other, the first connection parts and the first via define a surface of the first electrode terminal that is entirely uncovered by the encapsulation material at the first end surface of the coil substrate and in contact with the first external electrode, and the second connection parts and the second via define a surface of the second electrode terminal that is entirely uncovered by the encapsulation material at the second end surface of the coil substrate and in contact with the second external electrode.

3 . The inductor as claimed in claim 1 , wherein
in a first outermost structure of the stacked structures in a stacking direction of the stacked structures, the first connection part extends from the conductive track, and in a second outermost structure of the stacked structures in the stacking direction of the stacked structures, the second connection part extends from the conductive track.

4 . The inductor as claimed in claim 1 , wherein
the wiring layer is covered with a first insulating layer and a second insulating layer in each of the stacked structures, and a third insulating layer is interposed between the stacked structures.

5 . The inductor as claimed in claim 4 , wherein at least one of the first, second, and third insulating layers has an elastic modulus of 3 GPa or more, and at least another one of the first, second, and third insulating layers has an elastic modulus of less than 3 GPa.

6 . The inductor as claimed in claim 1 , wherein
a through hole is formed through the coil substrate, and the through hole is filled with the encapsulation material.

7 . The inductor as claimed in claim 6 , wherein the conductive tracks include end faces facing toward the through hole, the end faces being covered with an insulating film.

8 . A method of manufacturing an inductor including a coil substrate, the coil substrate including a helical coil and first and second electrode terminals connected to a first end and a second end, respectively, of the helical coil, the method comprising:
forming a plurality of structures each including a metal layer and a first connection part and a second connection part on opposite sides of the metal layer, the metal layer and the first and second connection parts being in a single layer; and forming a laminate by sequentially stacking the structures, wherein said forming the laminate includes connecting the metal layers of the structures in series; connecting the first connection parts of the structures by a first via to form the first electrode terminal; and connecting the second connection parts of the structures by a second via to form the second electrode terminal.

9 . The method as claimed in claim 8 , further comprising:
forming the helical coil by simultaneously processing the metal layers connected in series so that each of the metal layers has a shape of a part of the helical coil; and covering the laminate with an encapsulation material containing a magnetic material after forming the helical coil.

10 . The method as claimed in claim 9 , further comprising:
cutting the laminate covered with the encapsulation material at predetermined positions, wherein in cutting the laminate, the first connection parts and the first via are cut in a stacking direction of the structures so that cut surfaces of the first connection parts and the first via are exposed at a first end surface of the laminate, and the second connection parts and the second via are cut in the stacking direction of the structures so that cut surfaces of the second connection parts and the second via are exposed at a second end surface of the laminate opposite to the first end surface.

11 . The method as claimed in claim 9 , wherein
said simultaneously processing the metal layers forms a through hole penetrating through the laminate, and said covering the laminate includes filling the through hole with the encapsulation material.

Assignees

• Shinko Electric Ind Co
• Tokyo Coil Eng Co Ltd

Inventors

• Horikawa Yasuyoshi
• Nakanishi Tsukasa
• Okita Kazuyuki
• Miyasaka Yukihiro

Classifications

• H01F3/08

  made from powder (powder coatings on sheets H01F3/02; on strips or ribbons H01F3/04; on wires H01F3/06) · CPC title

• H01F41/005

  Impregnating or encapsulating (insulating of windings H01F41/12) · CPC title

• H01F41/041

  Printed circuit coils (apparatus or processes for manufacturing printed circuits in general H05K3/00) · CPC title

• H01F5/003 Primary

  Printed circuit coils · CPC title

• H01F27/2804

  Printed windings · CPC title