COIL COMPONENT

• US 20140009254A1
• Filed: 07/03/2013
• Published: 01/09/2014
• Est. Priority Date: 07/04/2012
• Status: Active Grant

• Current Assignee: TDK Corporation
• Original Assignee: TDK Corporation
• Inventors: OHKUBO, Hitoshi, ITO, Tomokazu, MAEDA, Yoshihiro, OHTA, Manabu, KANAME, Yuuya, NAKAGAWA, Takashi, ITOH, Hideto, KAWAHARA, Takahiro
• Granted Patent: US 9,142,343 B2
• Time in Patent Office: Days
• US Class Current: 336/192
• CPC Class Codes: H01F 17/0033 with the coil helically wound around a magnetic core
• CPC Class Codes: H01F 2017/0073 with a special conductive pattern, e.g. flat spiral
• CPC Class Codes: H01F 2027/2809 on stacked layers
• CPC Class Codes: H01F 27/022 Encapsulation
• CPC Class Codes: H01F 27/255 made from particles H01F27/26 takes precedence
• CPC Class Codes: H01F 27/2804 Printed windings
• CPC Class Codes: H01F 27/29 Terminals; Tapping arrangements for signal inductances
• CPC Class Codes: H01F 27/292 Surface mounted devices

Abstract

A coil component 1 includes a substrate 2, a planar spiral conductor 10a formed on a top surface 2t of the substrate 2, a lead conductor 11a connected to an outer peripheral end of the planar spiral conductor 10a, a dummy lead conductor 15a formed on the top surface of the substrate 2 and between an outermost turn of the planar spiral conductor 10a and an end 2X₂ of the substrate 2 and free from an electrical connection with another conductor within the same plane, external electrodes 26a and 26b arranged in parallel with the top surface of the substrate 2, and a bump electrode 25a formed on a surface of the lead conductor 11a and connects the lead conductor 11a with the external electrode 26a. The external terminals 26a and 26b have a larger area than the bump electrodes 15a and 15b for securing a bonding strength.

Claims

1. A coil component comprising:

a substrate;

a planar spiral conductor that is formed on a surface of the substrate by electrolytic plating;

a lead conductor that is formed on the surface of the substrate and connected to an outer peripheral end of the planar spiral conductor;

a dummy lead conductor that is formed on the surface of the substrate and between an outermost turn of the planar spiral conductor and an end of the substrate, and free from an electrical connection with another conductor at least within the same plane;

an external electrode that is formed in parallel with the surface of the substrate; and

a bump electrode that is formed on a surface of the lead conductor by electrolytic plating and connects the lead conductor with the external electrode, wherein

the external electrode has an area greater than that of the bump electrode.

2. The coil component as claimed in claim 1, wherein

the planar spiral conductor has a circular spiral shape, and

a side surface of the dummy lead conductor opposed to the planar spiral conductor is curved along the outermost turn of the planar spiral conductor.

3. The coil component as claimed in claim 1 further comprising:

an insulating resin layer that covers the planar spiral conductor, the lead conductor, and the dummy lead conductor; and

a metal magnetic powder-containing resin layer that covers the surface of the substrate from above the insulating resin layer, wherein

the external electrode is formed not on a side surface but selectively on a main surface of the metal magnetic powder-containing resin layer, and

the bump electrode penetrates the insulating resin layer and the metal magnetic powder-containing resin layer and is connected to the external electrode.

4. The coil component as claimed in claim 3 further comprising first and second through-hole magnetic bodies that are made of the same material as that of the metal magnetic powder-containing resin layer, wherein

the first through-hole magnetic body penetrates the substrate in a center portion surrounded by the planar spiral conductor, and

the second through-hole magnetic body penetrates the substrate outside the planar spiral conductor.

5. The coil component as claimed in claim 4, wherein

the substrate has a rectangular shape,

the planar spiral conductor has an elliptical spiral shape, and

the second through-hole magnetic bodies are formed corresponding to each of four corners of the substrate.

6. The coil component as claimed in claim 5, wherein

the substrate includes first and second sides that are parallel to each other, and third and fourth sides that are orthogonal to the first and second sides and parallel to each other,

the lead conductor is extended along the first side,

the dummy lead conductor is extended along the second side and

the second through-hole magnetic bodies are arranged on the third or fourth sides.

7. The coil component as claimed in claim 6, wherein

the bump electrode is extended along the first side with the lead conductor.

8. A coil component comprising:

a substrate having top and bottom surfaces;

a first planar spiral conductor that is formed on the top surface of the substrate by electrolytic plating;

a second planar spiral conductor that is formed on the bottom surface of the substrate by electrolytic plating;

a first through-hole conductor that penetrates the substrate to connect an inner peripheral end of the first planar spiral conductor with an inner peripheral end of the second planar spiral conductor;

a first dummy lead conductor that is formed on the top surface of the substrate and between an outermost turn of the first planar spiral conductor and an end of the substrate, and free from an electrical connection with another conductor at least within the same plane;

a second dummy lead conductor that is formed on the bottom surface of the substrate and between an outermost turn of the second planar spiral conductor and an end of the substrate, and free from an electrical connection with another conductor at least within the same plane;

a first lead conductor that is formed on the top surface of the substrate and vertically overlapped with the second dummy lead conductor, and is connected to an outer peripheral end of the first planar spiral conductor;

a second lead conductor that is formed on the bottom surface of the substrate and vertically overlapped with the first dummy lead conductor, and is connected to an outer peripheral end of the second planar spiral conductor;

a second through-hole conductor that penetrates the substrate to connect the first dummy lead conductor with the second lead conductor;

first and second external electrodes that are formed in parallel with the top surface of the substrate;

a first bump electrode that is formed on a surface of the first lead conductor by electrolytic plating and connects the first lead conductor with the first external electrode; and

a second bump electrode that is formed on a surface of the first dummy lead conductor by electrolytic plating and connects the first dummy lead conductor with the second external electrode, wherein

the first external electrode has an area greater than that of the first bump electrode, and

the second external electrode has an area greater than that of the second bump electrode.

9. The coil component as claimed in claim 8, wherein

the first and second planar spiral conductors have a circular spiral shape,

a side surface of the first dummy lead conductor opposed to the first planar spiral conductor is curved along the outermost turn of the first planar spiral conductor, and

a side surface of the second dummy lead conductor opposed to the second planar spiral conductor is curved along the outermost turn of the second planar spiral conductor.

10. The coil component as claimed in claim 9 further comprising:

a first metal magnetic powder-containing resin layer that is arranged on a top surface side of the substrate; and

a second metal magnetic powder-containing resin layer that is arranged on a bottom surface side of the substrate,

wherein

the first and second external electrodes is formed not on a side surface but selectively on a main surface of the first metal magnetic powder-containing resin layer,

the first and second bump electrodes penetrate the first metal magnetic powder-containing resin layer and are connected to the first and second electrode external electrodes, respectively.

11. The coil component as claimed in claim 10 further comprising first and second through-hole magnetic bodies that are made of the same material as that of the first and second metal magnetic powder-containing resin layers, and penetrate the substrate to connect the first metal magnetic powder-containing resin layer with the second metal magnetic powder-containing resin layer, wherein

the first through-hole magnetic body penetrates the substrate in a center portion surrounded by the first and second planar spiral conductors, and

the second through-hole magnetic bodies penetrate the substrate outside the first and second planar spiral conductors.

12. The coil component as claimed in claim 11 wherein

the substrate has a rectangular shape,

the first and second planar spiral conductors have an elliptical spiral shape, and

the second through-hole magnetic bodies are formed corresponding to each of four corners of the substrate.

13. A coil component comprising:

a substrate;

first and second spiral conductors that are formed on one and the other of main surfaces of the substrate, respectively;

a first terminal electrode that is formed on the one main surface and connected to an outer peripheral end of the first spiral conductor;

a second terminal electrode that is formed on the other main surface and connected to an outer peripheral end of the second spiral conductor;

a first through-hole conductor that penetrates the substrate to connect inner peripheral ends of the first and second spiral conductors each other;

a first dummy terminal electrode that is formed on the one main surface and vertically overlapped with the second terminal electrode;

a second dummy terminal electrode that is formed on the other main surface and vertically overlapped with the first terminal electrode;

a second through-hole conductor that penetrates the substrate to connect the first dummy terminal electrode with the second terminal electrode;

a first metal magnetic powder-containing resin layer that is formed on the one main surface and covers the first spiral conductor, the first terminal electrode, and the first dummy terminal electrode;

a second metal magnetic powder-containing resin layer that is formed on the other main surface and covers the second spiral conductor, the second terminal electrode, and the second dummy terminal electrode;

a first lead electrode that penetrates the first metal magnetic powder-containing resin layer and is connected to a top surface of the first terminal electrode; and

a second lead electrode that penetrates the first metal magnetic powder-containing resin layer and is connected to a top surface of the first dummy terminal electrode, wherein

outer side surfaces of the first and second terminal electrodes, the first and second dummy terminal electrodes, and the first and second lead electrodes are each exposed without being covered with the first and second metal magnetic powder-containing resin layers, and

side surfaces of the substrate lying on the same planes as the outer side surfaces of the first and second terminal electrodes are exposed without being covered with the first and second metal magnetic powder-containing resin layers.

14. The coil component as claimed in claim 13, wherein

the substrate includes first and second side surfaces that are parallel to each other, and third and fourth side surfaces that are orthogonal to the first and second side surfaces,

the first side surface of the substrate forms the same plane as the outer side surface of the first terminal electrode and the outer side surface of the second dummy terminal electrode, and

the second side surface of the substrate forms the same plane as the outer side surface of the second terminal electrode and the outer side surface of the first dummy terminal electrode.

15. The coil component as claimed in claim 13 further comprising a through-hole magnetic body that penetrates a corner portion of the substrate to connect the first metal magnetic powder-containing resin layer with the second metal magnetic powder-containing resin layer, wherein

the first and second sides of the substrate are arranged in areas excluding the forming area of the through-hole conductor.

16. The coil component as claimed in claim 15 further comprising first and second external electrodes that are formed on a main surface of the first metal magnetic powder-containing resin layer and connected to the first and second lead electrodes, respectively, wherein

the first external electrodes constitutes a first L-shaped electrode with the first lead electrode, the first terminal electrode, and the first dummy terminal electrode, and

the second external electrode constitutes a second L-shaped electrode with the second lead electrode, the second terminal electrode, and the second dummy terminal electrode.