JPH10208939A - Smd type coil and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make the inductance increase of a coil possible and obtain small-sized and low-priced electronic appliances. SOLUTION: Forming circular long-hole-form through holes 3a, 3b outside and inside a magnet storing recessed groove formed in a first insulation board 2a, and forming a copper plated layer on the whole surface of the insulation board 2a, inclusive of the inner surfaces of the through holes 3a, 3b, etching treatments are so performed thereafter as to form electrode portions 4 on both opposite side surfaces of the insulation boards and as to form a plurality of vertical patterns A, B on vertical wall portions 3A, 3B of the through holes 3a, 3b and as to form radial copper-foil patterns 5 for connecting thereby the vertical patterns A, B. After applying a bonding agent to a jointing portion 11 of two insulation boards 2a, 2b, a magnet is mounted in the recessed groove. After aligning and bonding the two insulation boards 2a, 2b to each other, the electric continuity of the vertical patterns A, B and the connection portions of the electrode portions 4 is secured by re-plating treatments, and surrounding the magnet, a closed-loop-form coil is formed out of the radial copper-foil patterns 5 and the vertical patterns A, B. Thereby many SMD type coils are massproduced using a collective insulation board to make respective very thin, small-sized, and low-priced coils realizable.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a portable telephone, a PHS,
The present invention relates to an SMD coil used for general electronic devices such as a personal computer and a method for manufacturing the same.

[0002]

2. Description of the Related Art In recent years, electronic devices have been pursuing high performance and multiple functions, as well as miniaturization and weight reduction. Mobile phone, P
HS, a personal computer, etc. are examples. Inductors used in these electronic devices must be SMDs.

[0003] An inductor is an impedance element utilizing an electromagnetic effect generated by passing a current through a conductive wire wound around a core such as a ferrite. Due to this principle, the structure is more complicated than that of other passive components, and the implementation of SMD is relatively delayed.

[0004] Compared with a chip coil conductor using a general winding, a thin-film chip inductor can be said to be a small-sized and high-precision coil conductor due to a difference in manufacturing method. The technique is disclosed in Japanese Patent Application Laid-Open No. 5-82349. The outline will be described.

FIG. 14 is a sectional view of a conventional spiral thin film coil, and FIG. 15 is a plan view thereof. The outline of the manufacturing process is as follows: a plurality of low-resistance spiral thin-film coil conductors 22A, 22B, and 22C mainly composed of copper are provided on the surface of an insulating substrate 21 made of a low-dielectric-constant ceramic wafer serving as a base;
In the thickness direction, insulating layers 23A and 23B made of a low-dielectric-constant heat-resistant resin coating film are stacked and provided in a multilayered manner, and at least the winding start end 24 and the winding end end 24 of the thin-film coil conductors 22A, 22B and 22C respectively The thin film coil conductors 22A, 22B and 22C are electrically connected.

[0006]

However, the above-mentioned spiral thin-film coil has the following problems. That is, it is difficult to increase the number of coil turns in the planar type SMD type coil, and it is difficult to increase the coil inductance.

The present invention has been made in view of the above-mentioned conventional problems, and has as its object to increase the inductance of a coil, to reduce the size and weight of electronic equipment,
An object of the present invention is to provide an ultra-thin and small planar SMD coil which realizes cost reduction and a method of manufacturing the same.

[0008]

In order to achieve the above object, an SMD type coil according to the present invention is provided with a magnet housing groove at a substantially central portion on the back surface of a substantially rectangular insulating substrate made of a PCB substrate or a ceramic body. Forming a slot-shaped through hole near the outside and inside of the magnet storage groove, forming a copper plating layer on the entire surface of the insulating substrate including the inside of the slot-shaped through hole, and etching. The electrode portion on the opposite side surface of the insulating substrate, a plurality of vertical patterns on the vertical wall portion of the outer and inner elongated through-holes, and the outer and inner surfaces facing each other on the upper surface of the insulating substrate. A first or second insulating substrate formed with a radial copper foil pattern connecting vertical patterns adjacent to each other;
The magnet storage grooves of the insulating substrate are opposed to each other, and a magnet is mounted on the magnet storage grooves, aligned, adhered and joined, and then re-plated to conduct the vertical pattern and the electrode portions of the two insulating substrates. By letting
The upper and lower radial copper foil patterns surrounding the magnet are continuously connected via the vertical pattern to form a closed loop.

Further, of the first or second insulating substrate,
One of the insulating substrates is made of an insulator made of a PCB substrate or a ceramic body, and the other is made of an insulator made of a polyimide film or the like.

Further, the first or second insulating substrate is an insulator made of a polyimide film or the like.

Further, the method of manufacturing an SMD coil according to the present invention is characterized in that a plurality of collective insulating substrates, such as a PCB substrate or a ceramic body, are located on the back surface at the substantially central portion of each row, Forming a magnet receiving groove, an elongated through hole outside and inside the magnet receiving groove, a through hole processing step of providing an elongated through hole between the rows, and a plating process. A plating step of forming a copper plating layer on the entire surface of the collective insulating substrate including the inner surface of the outer and inner elongated through-holes and the elongated through-hole between each row, laminating a plating resist, and exposing and developing. After forming a pattern mask and performing pattern etching, an electrode portion is provided on the opposite side surface of the collective insulating substrate, and a plurality of vertical patterns are provided on the vertical wall portions of the outer and inner elongated through holes. A first or second collective insulating substrate processing step of forming a radial copper foil pattern connecting the outer and inner opposing and close vertical patterns on the upper surface of the collective insulating substrate; and the first or second collective A magnet mounting step of mounting a magnet on each one of the magnet housing grooves of the insulating substrate, and stacking the two collective insulating substrates such that the magnet housing grooves of the first or second collective insulating substrate face each other; A bonding step of aligning, bonding and bonding both bonded parts, and a re-plating step of conducting each vertical pattern and an electrode part to be bonded to the integrated assembly by re-plating processing; and A dicing step of dividing the body into a single SMD coil including one magnet.

One of the first and second collective insulating substrates is made of a collective insulator such as a PCB substrate or a ceramic body, and the other collective insulating substrate is made of a polyimide film or the like. It is characterized by being a body.

Further, the first or second collective insulating substrate includes:
Both are collective insulators made of a polyimide film or the like.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An SMD type coil and a method for manufacturing the same according to the present invention will be described below with reference to the drawings.
1 to 11 relate to a two-substrate cored SMD coil and a method of manufacturing the same according to a first embodiment of the present invention.
1 is a perspective view of the front side of the first insulating substrate of the SMD type coil alone, FIG. 2 is a plan view of FIG. 1, FIG. 3 is a perspective view of the back side taken along the line AA of FIG. 1, and FIG. FIG. 5 is a cross-sectional view of a state in which a first insulating substrate and a second insulating substrate face each other, FIG. 6 is a cross-sectional view of a single SMD coil, and FIG.
FIG. 3 is a perspective view showing a state where a magnet is mounted in FIG. 3, and FIG. 8 is a perspective view showing a completed SMD type coil.

As shown in FIGS. 1 to 3, reference numeral 2a denotes a substantially rectangular first insulating substrate made of a PCB substrate or a ceramic body, and 9 denotes a ring located at a substantially central portion of the back surface of the first insulating substrate 2a. It is a magnet-shaped concave groove. 3a and 3b
Are two circular long hole-shaped through holes formed by processing means such as a press or an end mill in the vicinity of the outside and inside of the magnet accommodating groove 9. A copper plating layer is formed on the entire surface of the first insulating substrate 2a including the vertical wall portions 3A and 3B of the circular elongated holes 3a and 3b, and the opposite side surfaces of the first insulating substrate 2a are etched. And a vertical wall portion 3A which is opposed to and close to the electrode portion 4 and the through holes 3a and 3b in the form of the outer and inner circular elongated holes.
And 3B have a plurality of vertical patterns A and B (for example, A1, A2... AN and B1, B2.
N) and the vertical patterns A1 and B1, A2 and B2... AN-1 and BN-1 on the upper surface side of the first insulating substrate 2a.
Are formed, and radial patterns A and B formed on the vertical wall portions 3A and 3B are formed.
The cross section of the radial copper foil pattern 5 on the upper surface is connected to a U-shape as shown in FIG. Second insulating substrate 2b
Use a substrate having substantially the same dimensions and processing shape as the first insulating substrate 2a.

4 to 8, as shown in FIG.
10 is a magnet, a ring-shaped magnet made of cut or molded ferrite, samarium cobalt, etc.
As shown in FIG. 5, the first insulating substrate 2a and the magnet housing groove 9 of the second insulating substrate 2b face each other,
After applying an adhesive to be described later, the magnet 10 is mounted in the magnet housing groove 9.

For the most efficient size of the magnet 10, it is preferable to bring the magnet 10 close to the inside of the closed loop to the last minute. Therefore, a magnet having the size of the last minute of the closed loop is most suitable. Magnet 1
The cross-sectional shape of 0 is not limited to a square shape as shown in FIG.

In FIG. 6, an adhesive 1 is applied to one of the joints 11 between the first insulating substrate 2a and the second insulating substrate 2b.
2 or a sheet-like adhesive 12 is applied and aligned, bonded or bonded by thermocompression bonding, and then the first insulating substrate 2a and the second insulating substrate 2 are re-plated.
b, the magnets 10 are surrounded by conducting at the connection portions 3d of the vertical patterns A and B and the connection portions 4c of the electrode portions 4, and as shown in FIG.
1, A2 and B2... AN-1 and BN-1 are connected by a radial copper foil pattern 5, respectively.
B2 and A3... BN-1 and AN are connected by the radial copper foil pattern 5, respectively, and the upper and lower patterns start winding at the end of the coil via the radial copper foil pattern 5 and the plurality of vertical patterns A and B. 4a and coil end winding end 4b
Is a closed-loop S connected as a single continuous line
An MD coil 1 is configured.

Referring to FIGS. 9 and 10, a description will be given of the manufacturing method. First, as shown in FIG. 9, a plurality of ring-shaped substrates are positioned at substantially the center of each row on the back surface of the first collective insulating substrate 6a formed of the PCB substrate or the ceramic body. A magnet housing groove 9 is formed, and circular elongated holes 3a and 3b are formed near the outer and inner sides of each magnet housing groove 9 and an elongated hole 3c is formed between the rows. Alternatively, a through hole processing step formed by a processing means such as an end mill is performed.

Next, in the first plating step, after cleaning the entire surface of the first collective insulating substrate 6a including the wall surfaces of the circular elongated hole-shaped through holes 3a and 3b and the elongated hole shaped through hole 3c, By electrolytic plating and electrolytic plating, a copper plating layer is formed on the entire surface including the inner surfaces of the circular elongated hole-shaped through holes 3a and 3b and the elongated hole-shaped through hole 3c.

Further, in the etching step, a plating resist is laminated, a pattern mask is formed after exposure and development, and pattern etching is performed. Longitudinal wall portion 3 of elongated hole-shaped through holes 3a and 3b
A, 3B, a plurality of vertical patterns A, B, and a radial pattern that connects the opposed vertical patterns A, B formed on the vertical wall portions 3A, 3B on the upper surface of the first collective insulating substrate 6a. By forming the copper foil pattern 5, the first collective insulating substrate 6a is completed. After the etching step, the extra resist film for protection is peeled off with a peeling liquid.

In the magnet mounting step, as shown in FIGS. 5 and 6, the first collective insulating substrate 6a and the second
An epoxy 12 or a silicone adhesive 12 is printed and applied to a required portion using a mask on any one of the joints 11 of the collective insulating substrate 6b, or a sheet-like adhesive 12 is applied in advance. The magnet 10 is mounted on the magnet housing groove 9 of one of the two collective insulating substrates 6a and 6b.

In the bonding step, the first collective insulating substrate 6a and the second collective insulating substrate
b, the first collective insulating substrate 6a and the second collective insulating substrate 6b are overlapped with each other so that the magnet accommodating concave grooves 9 face each other, and the connection portions 3d of the vertical patterns A and B and the connection portions 4c of the electrode portions 4 are formed.
And the two joint insulating substrates 6a and 6b are integrally joined by bonding or thermocompression bonding the joining portion 11. An integrated assembly 13 is formed.

The alignment between the first collective insulating substrate 6a and the second collective insulating substrate 6b is previously performed.
This is reliably performed by using a jig (not shown) by the alignment guide holes 6c provided at the corners of b.

It is needless to say that the order of mounting the magnet 10 and applying the adhesive 12 to the first collective insulating substrate 6a or the second collective insulating substrate 6b may be reversed.

In the second plating step, the integrated assembly 13 is again subjected to a copper plating process, and
3 reliably connects the connection portions 3d of the vertical patterns A and B and the connection portions 4c of the electrode portions 4 to each other. Accordingly, the first collective insulating substrate 6a and the second collective insulating substrate 6b surround the ring-shaped magnet 10, and the upper and lower radial copper foil patterns 5 are wound through the vertical patterns A and B at the coil end winding start portion 4a. And the coil end winding end portion 4b are continuously connected as one continuous line to form a closed loop.

In the dicing step of dividing the integrated assembly 13, the alignment guide hole 6 c is used to divide the integrated assembly 13 into a single SMD coil including one magnet 10.
Is set on a jig (not shown), and cut and separated into one chip by a dicing or slicing machine along the orthogonal X direction 7 and Y direction 8 to complete the SMD type coil 1.

As described above, in order to insulate the radial copper foil pattern 5 exposed on the upper and lower surfaces, the integrated assembly 1
Before cutting 3, a resist film may be formed by processing such as resist coating.

FIG. 11 is a plan view showing the shape of the elongated through-holes 3a and 3b formed doubly on the first insulating substrate 2a or the second insulating substrate 2b outside and inside the magnet housing groove 9. FIG. FIG. 10 (a) illustrates one through hole 3a and 3b in the shape of a circular long hole, FIG. 10 (b) illustrates the case described in the present embodiment, and divides it into two by two, and FIG. 3 lines each, (d) is divided into 4 and 4 lines each, (e) is L
It shows an example of two through holes 3e and 3f in the shape of a letter-shaped long hole. Any shape may be adopted in the through hole processing step.

FIG. 12 shows a second embodiment of the present invention. In FIG. 10, the two-board SMD type coil 1
In order to further reduce the thickness, for example, the first insulating substrate 2a is an insulator made of a PCB substrate or a ceramic body, and the second insulating substrate 2c is an insulator made of a polyimide film or the like. The cored SMD coil 1A of the substrate can be manufactured.

FIG. 13 shows a third embodiment of the present invention. In FIG. 10, the two-board SMD type coil 1
In order to reduce the thickness of the SMD, for example, the first insulating substrate 2d and the second insulating substrate 2e are both made of an insulator made of a polyimide film, etc.
The mold coil 1B can be manufactured.

[0032]

As described above, according to the present invention,
A slot-shaped through-hole is formed outside and inside the magnet housing groove formed on the back surface of the insulating substrate, which is located at a substantially central portion of an insulating substrate made of a PCB substrate or a ceramic body, and the etching process is performed. Electrodes are formed on opposing side surfaces of the insulating substrate, a plurality of vertical patterns are formed on the vertical wall portions of the long hole-shaped through holes, and a radial copper foil pattern connecting the vertical patterns is formed. The two insulating substrates surround the magnet by opposing the storage grooves, mounting the magnet, aligning, bonding, and joining the magnet, and the upper and lower radial copper foil patterns via the vertical pattern and the coil terminal winding start portion. When it is necessary to increase the inductance of the coil by forming it as a continuous line with the coil end winding end and forming a closed loop, The SMD type coils requiring greater number can be realized in a small and thin. Further, by making one or both of the insulating substrates an insulator made of a polyimide film or the like, it is possible to make the insulating substrate ultra-thin. In addition, since the manufacturing method is performed using a collective insulating substrate that is manufactured in a large number, manufacturing costs can be reduced. Therefore, a great effect can be achieved, such as reduction in size, weight, and cost of electronic devices.

[Brief description of the drawings]

FIG. 1 is a perspective view of a front surface side of a first insulating substrate of an SMD coil according to a first embodiment of the present invention.

FIG. 2 is a plan view of FIG.

FIG. 3 is a perspective view showing a cross section taken along line AA on the back surface side of FIG. 1;

FIG. 4 is a perspective view of a magnet.

5 is a cross-sectional view of a state where the first insulating substrate of FIG. 1 and a second insulating substrate having the first insulating substrate on the back surface side are opposed to each other.

FIG. 6 is a sectional view of a completed SMD coil.

FIG. 7 is a perspective view showing a state where a magnet is mounted in FIG. 3;

FIG. 8 is a perspective view of a completed SMD coil.

FIG. 9 is a perspective view of a first collective insulating substrate for explaining a method of manufacturing an SMD coil.

FIG. 10 is a perspective view of an integrated assembly obtained by bonding and bonding a first collective insulating substrate and a second collective insulating substrate.

FIG. 11 is a plan view showing the shape of a long through hole.

FIG. 12 is a sectional view of an SMD-type coil according to a second embodiment of the present invention.

FIG. 13 is a sectional view of an SMD-type coil according to a third embodiment of the present invention.

FIG. 14 is a sectional view of a conventional SMD type coil.

FIG. 15 is a plan view of FIG.

[Explanation of symbols]

 1, 1A, 1B SMD type coil 2a, 2d First insulating substrate 2b, 2c, 2e Second insulating substrate 3a, 3b Circular slot-shaped through hole 3c Slot-shaped through hole 3d, 4c Connection part 3e, 3f L L-shaped through hole 3A, 3B Vertical wall 4 Electrode 4a Coil winding start 4b Coil winding end 5 Radial copper foil pattern 6a First collective insulating substrate 6b Second collective insulating substrate 6c Positioning guide hole 9 Groove for magnet storage 10 Magnet 11 Joint 12 Adhesive 13 Integrated assembly A, B Vertical pattern

Claims (6)

[Claims] 1. A substantially rectangular insulating substrate made of a PCB substrate or a ceramic body, etc., having a magnet housing groove at a substantially central portion on the back surface thereof, and a slot-like through hole near the outside and inside of the magnet housing groove. A hole is formed, a copper plating layer is formed on the entire surface of the insulating substrate including the inner surface of the elongated hole, and an electrode portion is formed on an opposite side surface of the insulating substrate by an etching process. A first or second insulating member formed with a plurality of vertical patterns on a vertical wall portion of a hole-shaped through hole and a radial copper foil pattern connecting the outer and inner opposed vertical patterns on the upper surface of the insulating substrate; The substrate and the magnet receiving grooves of the first insulating substrate and the second insulating substrate are opposed to each other, and a magnet is mounted on the magnet receiving grooves, aligned, adhered and joined, and then re-plated to obtain An SMD type coil, wherein a vertical pattern and an electrode portion of two insulating substrates are electrically connected to each other, and the upper and lower radial copper foil patterns are continuously connected via the vertical pattern to form a closed loop around the magnet. 2. The method according to claim 1, wherein one of the first and second insulating substrates is made of an insulator made of a PCB substrate or a ceramic body, and the other is made of an insulator made of a polyimide film or the like. The SMD type coil according to claim 1, wherein: 3. The SMD coil according to claim 1, wherein the first and second insulating substrates are both insulators made of a polyimide film or the like. 4. A plurality of magnet accommodating grooves are formed at predetermined intervals on a back surface of a substantially central portion of each row of a collective insulating substrate formed of a plurality of PCB substrates or ceramic bodies. Slotted through-holes on the outside and inside of the storage groove, a through-hole processing step of forming a slot-shaped through-hole between the rows, and the outside and inside slotted through-holes by plating. Plating process to form a copper plating layer on the entire surface of the collective insulating substrate including the inner surface of the elongated through hole between each row, laminating plating resist, forming a pattern mask after exposure and development, and performing pattern etching Electrodes on opposite side surfaces of the collective insulating substrate, a plurality of vertical patterns on vertical walls of the outer and inner elongated through-holes, and the outer and inner surfaces on the upper surface of the collective insulating substrate. A first or second collective insulating substrate processing step of forming a radial copper foil pattern connecting longitudinal patterns that are opposed to each other, and a magnet is provided in each of the magnet storage grooves of one of the first and second collective insulating substrates. And mounting the two sets of insulating substrates so that the magnet storage grooves of the first or second sets of insulating substrates face each other, align the positions, and bond and bond the two bonded portions to integrate them. Bonding step, re-plating step of conducting the respective vertical patterns and electrode portions to be joined by the re-plating process, and dicing for dividing the integrated body into a single SMD coil including one magnet. A method for manufacturing an SMD coil, comprising the steps of: 5. The first or second collective insulating substrate,
5. The SMD coil according to claim 4, wherein one of the collective insulating substrates is a collective insulator made of a PCB substrate or a ceramic body, and the other collective insulating substrate is a collective insulator made of a polyimide film or the like. Production method. 6. The method according to claim 4, wherein the first or second collective insulating substrate is a collective insulator made of a polyimide film or the like.