KR100541094B1 - Chip inductor and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a chip inductor capable of reducing parasitic capacitance and improving high frequency characteristics by forming a coil by folding a conductive metal strip in a predetermined direction to form a predetermined angle at a predetermined length.

The present invention is formed on a coil portion formed of a conductive metal and the surface of which is coated with an insulating material to form a spring, and a body portion integrally molding the periphery of the coil portion and both ends of the body portion. A chip inductor including an electrode part electrically connected to both ends of the coil part is provided.

According to the present invention, by reducing the parasitic capacitance in particular in the high frequency region is excellent in its characteristics, can reduce the DC resistance, there is an effect that can improve the contact between the coil and the electrode.

Chip Inductor, DC Resistance, Parasitic Capacitance, Strip, Stacked, Wired

Description

CHIP INDUCTOR AND MANUFACTURING METHOD THEREOF {CHIP INDUCTOR AND MANUFACTURING METHOD THEREOF}             

1 is an exploded view of a conventional stacked chip inductor.

2 is a perspective view of a conventional wire-wound chip inductor.

3 is a process chart showing a coil manufacturing method of a chip inductor according to the present invention.

4 is a flowchart illustrating a method of manufacturing a chip inductor according to the present invention.

* Description of the symbols for the main parts of the drawings *

31 ', 41: coil portion 32: body portion

33: electrode part 42: mold

43: paste

The present invention relates to a chip inductor and a method of manufacturing the same, and more particularly, by forming a coil by folding a conductive metal strip in a predetermined direction to form a predetermined angle at a predetermined length to reduce parasitic capacitance and improve high frequency characteristics. The present invention relates to a chip inductor and a method of manufacturing the same.

Recently, with the rapid development of electronic and communication devices, problems such as communication failures are frequently caused by mutual interference according to the frequency of frequent use of electronic and communication devices, and accordingly, they occur due to the use of wireless communication devices and multimedia devices. In order to improve the deteriorated electromagnetic environment, electromagnetic interference regulations in each country are being tightened.

In recent years, the development of electromagnetic interference elimination devices is required, and technology is being developed in terms of complexity, high integration, and high efficiency with the rapid increase in component demand. Among them, the chip inductor removes high frequency noise. As a filter, it is mainly used for personal computers, telephones, and communication devices.

As a chip inductor used in such a technique, a stacked chip inductor as shown in FIG. 1 and a wound chip inductor as shown in FIG. 2 have been used. First, the stacked chip inductor illustrated in FIG. 1 forms a via hole by punching a plurality of ceramic sheets 11, and forms a conductive pattern 12 according to the position of the via hole, and the conductive pattern 12 is formed. The plurality of ceramic sheets 11 were laminated and then fired.

In the conventional multilayer chip inductor, the characteristics of the product are determined in the printing and lamination process of the pattern. In the printing lamination process, the characteristics of the product vary according to the precision of the process, and in particular, the screen used for printing is deformed as the number of times of use increases. There is a problem that occurs. In addition, the conventional multilayer chip inductor has a problem in that an open defect may occur potentially due to breaks in a printed pattern and via holes. In the conventional stacked chip inductor, when the pattern is printed thick, a step problem occurs during lamination, and when the pattern is printed thinly to eliminate the step problem, the DC resistance increases. In addition, in the multilayer chip inductor, since the external electrodes formed on the left and right sides of the chip inductor and the patterns of all the layers are adjacent to each other, there is a problem in that the parasitic capacitance is increased and the characteristics thereof are deteriorated when used at high frequency.

FIG. 2 is a perspective view of a conventional wire-wound chip inductor. The wire 21 is wound directly on a ceramic core (not shown), and a case 22 is formed on the outside thereof, and then electrically contacts both ends of the wire 21. It comprises a electrode 23 formed on both ends of the 22. Such a conventional wire wound chip inductor is wound around the outside of the ceramic core, in particular, in the case of ferrite (leakage) may generate a leakage magnetic field may affect the peripheral circuit, and the insulation of the wire using enamel coating, etc. There is a problem of this deterioration. In addition, compared with the multilayer chip inductor described in FIG. 1, it is difficult to miniaturize and there is a problem that cannot be used for high capacitance.

Therefore, in the technical field, it is possible to solve problems such as changes in chip inductor characteristics and open defects, and it is required to develop a chip inductor that can reduce DC resistance and parasitic capacitance, and at the same time, can be miniaturized and used for high capacitance. .

Disclosure of Invention The present invention has been made to solve the above-described problems, and an object thereof is to provide a chip inductor capable of miniaturization and high capacity, and a method for manufacturing the chip inductor.

In order to achieve the above object, the present invention is a coil portion formed of a conductive metal and the surface of which is coated with an insulating material to form a spring, a body portion for integrally molding the periphery of the coil portion and the body Provided are chip inductors, each of which is formed at both ends of a portion and includes electrode portions electrically connected to both ends of the coil portion.

The coil unit may be formed by folding the strip by the same length and is formed by folding the strip at right angles.

The present invention also provides a method of manufacturing the chip inductor. Method for manufacturing a chip inductor according to the present invention,

Providing a mold made of a conductive metal and coated on the surface thereof with an insulating material, a mold filled with a molding paste, folding the strip to form a coil in a spring shape, and molding the coil into the mold. Immersing the paste and drying the paste to mold the coil, cutting the molded coil to a predetermined length, and electrically connecting both ends of the coil to both ends of the cut molding coil. And forming an electrode as possible.

Preferably, the forming of the coil is a step of forming the coil by folding the strip by the same length, and forming the coil by folding the strip at right angles.

The method of manufacturing a chip inductor according to the present invention may further include firing the molded coil to a predetermined temperature.

Hereinafter, with reference to the accompanying drawings will be described in more detail the configuration of the chip inductor according to the present invention.

3 is a process chart showing a coil manufacturing method of a chip inductor according to the present invention, in particular, Figure 3e is a perspective view of the chip inductor according to the present invention. Referring to FIG. 3E, the chip inductor according to the present invention includes a coil part 31 ′ formed of a conductive metal and a strip coated with an insulating material to form a spring, and the coil part 31 ′. It includes a body portion 32 for integrally molding the periphery of the and the electrode portion 33 is formed on both ends of the body portion 32, and electrically connected to both ends of the coil portion 31 '.

The coil portion 31 ′ is formed in a spring shape by folding a long strip having a predetermined width in the same manner as shown in FIGS. 3A to 3D. A long strip having a predetermined width as shown in FIG. 3A is prepared, and folding begins as shown in FIG. 3B. Then, as shown in FIG. 3C, the strip is folded at positions spaced at predetermined intervals from the first folded position in the same direction as that of the folding in FIG. 3B to form the coil into a spring shape. Preferably, the folding angle is a right angle. And it is preferable to keep the space | interval between the said folding positions the same. The folding angle is not limited to a right angle, and the folding position does not necessarily have to maintain the same spacing, but in general, since the shape of the chip inductor has a rectangular parallelepiped shape, the folding angle should be at right angles and folding at the same interval. The appearance of the chip inductor is most preferred.

The body portion 32 is formed by integrally molding the coil portion 31 '. The material used for molding may be a paste obtained by mixing ceramic powder, resin and solvent. At this time, since the paste used is not for printing, its viscosity may be low. The ceramic is preferably a low temperature co-fired ceramic (LTCC) material or a ferrite material, and the resin is preferably polyvinyl butyral (PVB), ethyl cellulose (EC) or an acrylic resin. In addition, the solvent is preferably terpineol (terpineol), dihydroterpinol (DHT), butyl carbitol (BC) or an alcohol system that can dissolve the resin. The body portion 32 is formed into a predetermined shape, in particular a rectangular parallelepiped shape by infiltrating the paste evenly around the coil portion 31 '. That is, the body part 32 is formed to mold the coil part 31 'so that the coil part 31' is located therein.

The electrode part 33 is formed using metal such as silver (Ag) at both ends of the body part 32. At this time, both ends of the coil part 31 ′ formed inside the body part 32 should be in electrical contact with the electrode part 33. The electrode part 33 may be formed by applying an Ag paste to both ends of the body part 32 and then baking. Alternatively, the electrode part 33 may be formed using Ag-epoxy instead of using the Ag paste. When using the said Ag-epoxy, a baking process can be skipped.

The chip inductor according to the present invention configured as described above is characterized in that the coil is formed in a vertical structure. The chip inductor in which the coil is formed in a vertical structure faces only the outermost part of the coil with the external electrode, and since the middle part of the coil is separated from the external electrode, the parasitic capacitance is small, and thus, the characteristic is excellent in the high frequency region. In addition, the chip inductor according to the present invention can increase the thickness of the strip used as a coil, because the problem of step difference due to the stacking does not occur, it is possible to reduce the DC resistance (R _dc ), a predetermined width The contact between the coil and the electrode can be improved by forming the coil with a strip.

A method of manufacturing a chip inductor according to the present invention configured as described above will be described with reference to the accompanying drawings.

4 is a process chart showing step by step a method of manufacturing a chip inductor according to the present invention. First, as shown in FIG. 4A, a strip made of a conductive metal and coated with an insulating material on its surface, and a mold 42 filled with a molding paste 43 are provided, and the coil 41 is folded into a spring shape by folding the strip. To form.

The coil 41 is preferably formed in a spring shape by folding a strip having a predetermined width whose surface is insulated at right angles by the same length. The mold 42 includes a molding paste 43 for molding the coil 41, and the body portion of the chip inductor illustrated in FIG. 3E may be formed. The material of the molding paste 43 is preferably a mixture of ceramic powder, resin and solvent.

Subsequently, as illustrated in FIG. 4B, the coil 41 is immersed in the molding paste 42 filled in the mold 44, and then the paste is dried to mold the coil 41. At this time, the molding paste can be uniformly well penetrated between the coil 41 and the inside.

Then, as shown in Fig. 4c, the molded coil 42 'is cut to a predetermined length. At this time, it is preferable that the length to be cut is the length of the body portion of the individual chip inductor.

Subsequently, as shown in FIG. 4D, electrodes 43 are formed on both ends of the cut molding coil 45 so that both ends of the coil are in electrical contact with each other. The electrode 43 may be formed by applying an Ag paste to both ends of the cut molding coil and then baking. Alternatively, the electrode can be formed using Ag-epoxy instead of using the Ag paste. When using the said Ag-epoxy, a baking process can be skipped.

Such a method of manufacturing a chip inductor according to the present invention may further include, after cutting the molded coil, firing the cut molding coil to a predetermined temperature.

As described above, in the method of manufacturing a chip inductor according to the present invention, a plurality of coils may be molded at the same time by adjusting the shape of a mold, thereby improving productivity, and in some cases, the product yield may be flexibly adjusted. In addition, complicated processes such as placement, molding, punching, printing, and lamination used in stacked chip inductors can be omitted, thereby reducing the number of manufacturing facilities and materials.

The present invention described above is not limited by the above-described embodiment and the accompanying drawings, but by the appended claims. Therefore, it will be apparent to those skilled in the art that various forms of substitution, modification, and alteration are possible without departing from the technical spirit of the present invention described in the claims.

As described above, according to the present invention, since the coil of the chip inductor is formed in a vertical structure, the parasitic capacitance is small, so that the characteristic is excellent in the high frequency region, and the coil does not have a problem of generation of steps due to stacking. The thickness of the strip to be used can be increased, the DC resistance can be reduced, and the coil portion can be formed into a strip having a predetermined width, thereby improving the contact between the coil portion and the electrode portion. The chip inductor according to the present invention has the effect of preventing the occurrence of leakage magnetic fields by molding the periphery of the coil with a paste of the same material without using a core.

In addition, the chip inductor manufacturing method according to the present invention has the effect of reducing the product cost and improving the productivity by simplifying the product manufacturing process and manufacturing equipment.

Claims (7)

A coil part made of a conductive metal and whose surface is coated with an insulating material to form a spring shape; A body part integrally molding the periphery of the coil part; And Chip inductors respectively formed at both ends of the body portion, and including electrode portions electrically connected to both ends of the coil portion. The method of claim 1, wherein the coil unit, Chip inductor, characterized in that formed by folding the strip by the same length. The method of claim 1, wherein the coil unit, Chip inductor, characterized in that formed by folding the strip at a right angle. Providing a mold made of a conductive metal, the surface of which is coated with an insulating material, and a mold filled with a molding paste; Folding the strip to form a coil in a spring shape; Immersing the coil in a molding paste filled in the mold and drying the paste to mold the coil periphery; Cutting the molded coil to a predetermined length; And And forming electrodes at both ends of the cut molding coil so that both ends of the coil are in electrical contact with each other. The method of claim 4, wherein the forming of the coil comprises: And folding the strip by the same length to form a coil. The method of claim 4, wherein the forming of the coil comprises: And folding the strip at right angles to form a coil. The method of claim 4, wherein And firing the cut molding coil at a predetermined temperature.

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