JP2003243239A - Method of manufacturing laminated coil component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of efficiently manufacturing a laminated coil component which is provided with an inner conductor (coil conductor) that is large in thickness and small in resistance, free from the occurrence of the misalignment of the coil conductors with one another in their lamination due to the upheaval of an area where the coil conductors are provided, and uniform in characteristics. <P>SOLUTION: A laser beam 2 is made to pass through a diffraction grating 3 so as to be dispersed into a prescribed pattern, the prescribed pattern formed by the laser beam 2 is reflected by galvano-scan mirrors 4 driven by galvano- scan mirror drive means 7 at prescribed angles to irradiate a ceramic green sheet 10, whereby an eliminated part 15 provided with a non-through part 14 and a through part 13 is provided to the ceramic green sheet 10, a coil conductor is provided on the eliminated part 15 of the green sheet 10, and the green sheets 10 with the coil conductors are laminated. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a laminated coil component manufactured through a process of laminating ceramic green sheets having coil conductors.

[0002]

2. Description of the Related Art In recent years, multilayer ceramic electronic components are required to have improved electrical characteristics and downsized products at the same time.

Further, it is often required to increase the permissible current value so that the device can be used with a large current.

By the way, a laminated inductor, which is one of such laminated ceramic electronic components, usually has a structure in which a coil conductor is embedded in a ferrite magnetic body,
Generally, it is manufactured through the following steps.

First, a via hole is formed in a ferrite ceramic green sheet. Next, a coil conductor (internal conductor) is arranged on this ceramic green sheet by a method such as screen printing, and then this is laminated and pressure-bonded, and the coil conductor arranged on each ceramic green sheet is The vias are connected to each other to form a coil within the stack. Then, this laminated body is fired under predetermined conditions. Then, a conductive paste is applied to a predetermined position of the fired laminate (element) and baked to form an external electrode.

[0006]

In the laminated inductor manufactured through the above steps, when it is desired to increase the inductance, the inductance is usually increased by increasing the number of turns of the coil. There is. In order to increase the number of coil turns, it is necessary to reduce the sheet thickness and the internal conductor (coil conductor) thickness. However, when the thickness of the inner conductor (coil conductor) is reduced, there is a problem that the resistance value of the inner conductor increases and the allowable current value decreases.

On the other hand, in order to reduce the resistance value of the inner conductor,
When the thickness of the inner conductor is increased, stacking of the inner conductors is likely to occur when the ceramic green sheets are stacked and pressure-bonded, which causes a problem of large variation in characteristics.

The present invention solves the above-mentioned problems, and the internal conductor (coil conductor) has a large thickness and a low resistance, and the stacking occurs due to the bulging of the portion where the coil conductor is disposed. It is an object of the present invention to provide a laminated coil component manufacturing method capable of efficiently manufacturing a laminated coil component with less variation in characteristics.

[0009]

In order to achieve the above object, a method of manufacturing a laminated coil component according to the present invention (Claim 1) comprises: (a) a laser beam emitted from a laser light source;
Dispersing into a predetermined pattern shape through a diffraction grating, irradiating the dispersed laser beam to the ceramic green sheet, forming a removal portion having a non-penetrating portion and a penetrating portion on the ceramic green sheet, ( The method is characterized by including the steps of (b) disposing a coil conductor in the removing section and (c) laminating a ceramic green sheet having the coil conductor in the removing section.

A laser beam is passed through a diffraction grating to be split into a predetermined pattern shape and irradiated onto a ceramic green sheet to form a removed portion having a non-penetrating portion and a penetrating portion on the ceramic green sheet. By stacking the ceramic green sheets obtained by arranging the coil conductors in the removed portion, the thickness of the coil conductors is large, the resistance is small, and stacking occurs due to the portion where the coil conductors are arranged rising. It is possible to manufacture a highly reliable laminated coil component that does not have any defects.

Further, in the method of manufacturing a laminated coil component according to the present invention (claim 2), (a) a laser beam emitted from a laser light source is passed through a diffraction grating and dispersed into a predetermined pattern shape, The separated laser beam is reflected by the galvano scan mirror driven by the galvano scan mirror driving means at a predetermined reflection angle and irradiated on the ceramic green sheet, and the ceramic green sheet has a non-penetrating portion and a penetrating portion. A step of forming a portion, (b) a step of arranging a coil conductor in the removing portion, and (c) a step of laminating a ceramic green sheet having a coil conductor in the removing portion. I am trying.

The laser beam is passed through a diffraction grating to be split into a predetermined pattern shape, and the laser beam is reflected at a predetermined reflection angle by a galvanoscan mirror driven by a galvanoscan mirror driving means to irradiate the ceramic green sheet, By forming a removed portion having a non-penetrated portion and a penetrated portion on the green sheet and stacking a ceramic green sheet obtained by disposing a coil conductor in the removed portion, the thickness of the coil conductor is large and low. Despite the resistance, it is possible to efficiently manufacture a highly reliable laminated coil component in which the stacking of coil coil conductors does not cause stacking. That is, by using a galvano scan mirror and a galvano scan mirror driving means and changing the reflection angle of the galvano scan mirror and repeating irradiation of the laser beam to the ceramic green sheet, the ceramic green sheet is irradiated in a predetermined area. Without moving the seat
It becomes possible to form the removal portion having a predetermined pattern shape at a plurality of positions, and it becomes possible to efficiently manufacture a highly reliable laminated coil component.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The features of the present invention will be described in more detail below.

FIG. 1 is a diagram showing a schematic configuration of a ceramic green sheet processing apparatus used for carrying out the method for manufacturing a laminated coil component of the present invention. 2 is a diagram showing a ceramic green sheet having a removed portion formed by using the processing apparatus shown in FIG. 1, (a) is a perspective view showing the entire ceramic green sheet, and (b) is a structure of the removed portion. It is an expansion perspective view.

In this embodiment, a ceramic green sheet used for manufacturing a laminated coil component is processed to
As shown in FIG. 2, a penetrating portion (through hole) having a substantially L-shaped planar shape and penetrating the ceramic green sheet 10.
A case will be described as an example in which the removing portion 15 including the non-penetrating portion (bottomed concave portion) 14 that does not penetrate the ceramic green sheet 10 is formed. The through portion (through hole) 13 is a portion that will function as a via hole in a product (multilayer coil component), and the through portion (through hole) 13 is a portion with an inclined bottom surface (bottom inclined portion). ) 14a.

Further, the processing apparatus used in this embodiment is
As shown in FIG. 1, supporting means (XY table in this embodiment) 11 configured to support the ceramic green sheet 10 and move the ceramic green sheet 10 in a predetermined direction, and a laser light source. 1 and a laser beam 2 emitted from the laser light source 1.
Through a plurality of predetermined pattern shapes (the predetermined pattern shape removing portion 1 of the ceramic green sheet 10).
5 (the shape corresponding to FIG. 2))
The galvanoscan mirror 4 that reflects the laser beam 2 that has passed through the diffraction grating 3 and has been separated into a predetermined pattern shape at a predetermined reflection angle, and the laser beam 2 that is reflected by the galvanoscan mirror 4 at a predetermined reflection angle, respectively. And a condenser lens 5 for condensing the laser beam, and the laser beam condensed through the condenser lens 5 is irradiated onto the ceramic green sheet 10 on the XY table 11.

This processing apparatus further moves a laser light source drive means 6 for driving the laser light source 1, a galvano scan mirror drive means 7 for changing the reflection angle of the galvano scan mirror 4, and an XY table 11 in predetermined directions. And the ceramic green sheet 10 supported on it.
Table driving means (moving means) 12 for moving the table in a predetermined direction.

Further, in this processing apparatus, a laser light source which emits a CO ₂ laser having a short pulse width is used as the laser light source 1. Further, ZnSe, which absorbs a small amount of CO ₂ laser, is used for the diffraction grating 3, the galvano scan mirror 4, and the condenser lens 5.

Further, in this processing apparatus, the diffraction grating 3
So that the removal portion 15 (FIG. 2) as described above can be formed on the ceramic green sheet 10 so that the laser beam has a predetermined pattern shape (the plane shape on the irradiation surface is a predetermined shape). Laser beam having a predetermined intensity at a predetermined portion of the pattern shape so that the shape (cross-sectional shape) in the depth direction of the removed portion 15 of the ceramic green sheet 10 becomes a predetermined shape. Is configured to be obtained.

Next, a method of forming a removal portion having a predetermined pattern shape on the ceramic green sheet by using the ceramic green sheet processing apparatus configured as described above will be described.

(1) First, a vinyl acetate binder is added to a ceramic containing NiCuZn ferrite as a main component,
After mixing in a ball mill for 17 hours, a ceramic green sheet 10 having a thickness of 50 μm and formed into a sheet by the doctor blade method is placed on the supporting means 11. (2) Then, the pulsed laser beam 2 emitted from the laser light source 1 of the CO ₂ laser generator for drilling with the rated output of 300 W is passed through the diffraction grating 3 to be dispersed into a predetermined pattern shape. (3) Then, the dispersed pulsed laser beam 2
Is reflected by the galvano scan mirror 4 and irradiated onto the ceramic green sheet 10 to remove a part of the ceramic green sheet 10 to form a removed portion 15 (FIG. 2). Here, the planar shape is substantially L-shaped and the width W = 1.
00 μm, depth T of non-penetrating part (recessed part with bottom) T = 20 m
m, depth T _MAX of the deepest part of the bottom inclined portion 14a = 50 μ
A removal portion 15 (FIG. 2) having a structure in which the diameter D of the through portion (through hole) 13 having a circular shape of m and a plane shape of D = 50 μm was formed. The laser beam 2 has an oscillation frequency of 1
Processing was performed under the conditions of kHz, pulse width = 50 μS (microsecond), and pulse energy = 1 mJ. (4) Then, the reflection angle of the galvanoscan mirror 4 is further changed, and the irradiation of the laser beam 2 on the ceramic green sheet 10 is repeated to form the removing portions 15 (FIG. 2) at different predetermined positions on the ceramic green sheet 10. Form. (5) Then, the step of irradiating the ceramic green sheet 10 with the laser beam 2 by changing the reflection angle of the galvano scan mirror 4 in (4) is repeated, and a predetermined area of the ceramic green sheet 10 (reflection of the galvano scan mirror) is repeated. By changing the angle, the removing unit 1 can be placed at different positions.
5 is removed in all areas)
After forming the XY table 11, the XY table 11 is moved by a predetermined amount and the steps (2) to (4) are repeated to remove the above-described pattern shape removing portion 15 at a predetermined position on the entire ceramic green sheet 10. To form.

According to the method of this embodiment, the diffraction grating 3
The ceramic green sheet 10 is irradiated with the laser beam 2 which has passed through the laser beam and is split into a plurality of predetermined pattern shapes to form the removed portion 15 (FIG. 2) having the predetermined pattern shape on the ceramic green sheet 10. Therefore, it is not necessary to use a mask, and the removal portion 15 can be efficiently formed at a predetermined position of the ceramic green sheet 10 with high energy efficiency.

Further, since the laser beam 2 is diffracted so that a large number of pattern shapes are formed when passing through the diffraction grating 3, it is possible to form a large number of removing portions 15 at the same time. Therefore, it becomes possible to form a large number of removed portions at a predetermined position with high efficiency and accuracy.

Further, by disposing the coil conductor in the removed portion (recess) 15 formed as described above, even when a large number of ceramic green sheets are laminated, the portion where the coil conductor is disposed rises. Therefore, it becomes possible to prevent stacking from occurring, and it is possible to obtain a laminated coil component with little variation in characteristics.

In the above embodiment, the case where the removed portion has a substantially L-shaped planar shape has been described as an example, but in the present invention, the shape (structure of the removed portion to be formed on the ceramic green sheet ) And dimensions are not particularly limited, and the removed portions of various patterns can be formed by changing the design pattern of the diffraction grating.

Further, the present invention can be applied to the case of forming the removed portion having various structures such as the removed portion of the unpenetrated structure which does not entirely penetrate the ceramic green sheet as the removed portion.

Further, although the CO ₂ laser is used in the above embodiment, other kinds of lasers can be used in the present invention.

In the above embodiment, the pulsed laser beam is used, but in some cases, a laser beam other than the pulsed laser beam may be used.

Further, in the above embodiment, the ceramic green sheet is directly placed on the XY table (supporting means) for processing, but the ceramic green sheet supported on the carrier film is supported together with the supporting means. It is also possible to place it on and process it. When the ceramic green sheet with a carrier film is processed, the ceramic green sheet can be handled while being supported by the carrier film, so the deformation and distortion of the ceramic green sheet can be suppressed and removed. It is possible to improve the dimensional accuracy and the positional accuracy of the part.

The invention of the present application is not limited to the above-described embodiment, and various applications and modifications can be made within the scope of the invention.

[0031]

As described above, according to the method for manufacturing a laminated coil component of the present invention (Claim 1), the laser beam is passed through the diffraction grating to be split into a predetermined pattern shape, and the ceramic green sheet is irradiated with the laser beam. Then, the removal portion having the unpenetrated portion and the penetration portion is formed on the ceramic green sheet, and the ceramic green sheet obtained by disposing the coil conductor in the removal portion is laminated. It is possible to efficiently manufacture a laminated coil component having a large conductor thickness, low resistance, and without stacking due to swelling of the portion where the coil conductor is disposed, and with less variation in characteristics.

In the method for manufacturing a laminated coil component according to the present invention (claim 2), a laser beam is passed through a diffraction grating to be split into a predetermined pattern shape, and the galvano scanning mirror driving means drives the galvano. By irradiating the ceramic green sheet by reflecting the light at a predetermined reflection angle with a scan mirror to form a removed portion having a non-penetrating portion and a penetrating portion on the ceramic green sheet and disposing a coil conductor in the removing portion. Since the obtained ceramic green sheets are stacked, the stack does not cause stacking due to swelling of the part where the coil conductor is placed, despite the large thickness of the coil conductor and low resistance. It is possible to efficiently manufacture a high-performance laminated coil component. That is, by using a galvano scan mirror and a galvano scan mirror driving means and changing the reflection angle of the galvano scan mirror and repeating irradiation of the laser beam to the ceramic green sheet, the ceramic green sheet is irradiated in a predetermined area. It is possible to form the removed portion having a predetermined pattern shape at a plurality of positions without moving the sheet, and it is possible to efficiently manufacture a highly reliable laminated coil component.

[Brief description of drawings]

FIG. 1 is a diagram showing a schematic configuration of a ceramic green sheet processing apparatus used for carrying out a method for manufacturing a laminated coil component of the present invention.

2 is a view showing a ceramic green sheet in which a removed portion is formed by processing the ceramic green sheet using the processing apparatus of FIG. 1 in the embodiment of the present invention, and FIG. FIG. 3B is an enlarged perspective view showing the structure of the removing portion.

[Explanation of symbols]

1 laser light source 2 laser beam 3 diffraction grating 4 galvano scan mirror 5 Condensing lens 6 Laser light source driving means 7 Galvano scan mirror driving means 10 Ceramic green sheet 11 Supporting means (XY table) 12 Table drive means 13 Through part (through hole) 14 Non-penetrating part (bottom recessed part) 14a Bottom inclined part 15 Removal section

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Masashi Morimoto             2-10-10 Tenjin, Nagaokakyo, Kyoto Stock             Murata Manufacturing Co., Ltd. F-term (reference) 5E062 DD04

Claims (2)

[Claims] (A) A laser beam emitted from a laser light source is passed through a diffraction grating to be dispersed into a predetermined pattern shape, and the dispersed laser beam is applied to a ceramic green sheet, A step of forming a removed portion having an unpenetrated portion and a penetrated portion; (b) a step of disposing a coil conductor in the removed portion; and (c) a ceramic green sheet having a coil conductor disposed in the removed portion. A method of manufacturing a laminated coil component, comprising: a step of laminating. 2. (a) A laser beam emitted from a laser light source is passed through a diffraction grating to be separated into a predetermined pattern shape, and then the separated laser beam is driven by a galvano scan mirror driving means. A step of forming a removed portion having a non-penetrating portion and a penetrating portion on the ceramic green sheet by irradiating the ceramic green sheet with a predetermined reflection angle by a scan mirror, and (b) providing a coil conductor in the removing portion. A method of manufacturing a laminated coil component, comprising: a step of arranging; and (c) a step of laminating a ceramic green sheet having a coil conductor arranged on the removed portion.