JP2010010321A - Method of manufacturing coil part - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a coil part that facilitates processing work and improves yield of products. <P>SOLUTION: The method of manufacturing the coil part includes: a step to mold a slurry into a sheet on a supporting base and form a ceramic green sheet; a step to apply a laser to the supporting base and the ceramic green sheet from the side of the supporting base so as to make through-holes and to fill the through-holes with a conductive material so as to form vias 8a and 8b; and a step to peel the supporting base from the ceramic green sheet and form conductor patterns 2-5 constituting one coil 9 and 10 on the upper and lower surfaces of the ceramic green sheet through the vias 8a and 8b. In the step for forming the ceramic green sheet, the thickness of the supporting base is made 1.0-2.0 times that of the ceramic green sheet. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method of manufacturing a coil component used in various electronic devices such as digital devices, AV devices, and information communication terminals.

  A conventional method for manufacturing this kind of coil component is to prepare a slurry by mixing a magnetic material powder mainly composed of ferrite, etc., with a binder mainly composed of polyvinyl butyral, etc., and an organic solvent. A ceramic green sheet is formed by forming a sheet on a support substrate by a blade method, and then a laser beam is irradiated to the support substrate and the ceramic green sheet from the support substrate side to form through-holes, respectively. A via was formed by filling the hole with a conductive material from the support substrate side. Thereafter, the supporting base is peeled off from the ceramic green sheet, and a conductor pattern constituting one coil is formed on the upper and lower surfaces of the ceramic green sheet through vias.

As prior art document information relating to the invention of this application, for example, Patent Document 1 is known.
JP-A-6-77073

  The above-described conventional coil component manufacturing method has a problem that the yield of products is poor.

  That is, when forming the through hole, the through hole is formed by irradiating the laser from the support substrate side, so the diameter of the through hole formed in the support substrate is larger than the diameter of the through hole formed in the ceramic green sheet. In addition, since the through holes formed in the support substrate and the ceramic green sheet are filled with the conductive material from the support substrate side, the conductive material that fills the through holes of the support substrate and constitutes the vias is formed. The amount is larger than the amount of the conductive material that fills the through hole of the ceramic green sheet and forms the via. As a result, when the support substrate is peeled from the ceramic green sheet, most of the conductive material that fills the through holes of the ceramic green sheet and constitutes the via is brought to the support substrate side (the via is brought back up). For this reason, the amount of the conductive material filled in the through hole of the ceramic green sheet is reduced, which causes a poor conduction of the coil, resulting in poor product yield.

  In addition, as a countermeasure against the above-mentioned defect, it may be possible to reduce the amount of conductive material filled in the through holes of the support substrate by wiping the surface of the support substrate with Bencotton soaked with an organic solvent. Becomes complicated and is not preferable.

  SUMMARY OF THE INVENTION The present invention solves the above-described conventional problems, and an object of the present invention is to provide a method for manufacturing a coil component that is easy to work and can improve product yield.

  In order to achieve the above object, the present invention has the following configuration.

  The invention according to claim 1 of the present invention includes a step of preparing a slurry by mixing ceramic powder, a binder and an organic solvent, and a step of forming a ceramic green sheet by forming the slurry into a sheet form on a supporting substrate. And forming a through hole by irradiating the support base and the ceramic green sheet with a laser from the support base side, and filling the through hole with a conductive material from the support base side to form vias, And removing the support substrate from the ceramic green sheet and forming conductor patterns constituting one coil on the upper and lower surfaces of the ceramic green sheet through the vias, and the slurry on the support substrate In the process of forming a ceramic green sheet by forming into a sheet shape, the thickness of the support substrate is The thickness of the Mick Green sheet is 1.0 to 2.0 times, and according to this manufacturing method, since the thickness of the support base can be reduced, the through holes of the support base are filled. This reduces the amount of conductive material that makes up the via, which prevents the conductive material that makes up the via of the ceramic green sheet from being taken to the support substrate side when the support substrate is peeled from the ceramic green sheet. Therefore, the effect of reducing the occurrence of coil conduction failure can be obtained.

  The invention according to claim 2 of the present invention is such that, in particular, the diameter of the via in the ceramic green sheet is smaller than the diameter of the via in the support base, and the difference is 55 μm or less. Since the amount of the conductive material that fills the through hole of the support base and configures the via can be reduced, when the support base is peeled from the ceramic green sheet, the conductive material that configures the via of the ceramic green sheet is placed on the support base side. It is possible to prevent them from being carried, thereby obtaining the effect of reducing the occurrence of poor coil conduction.

  As described above, the method for manufacturing a coil component according to the present invention includes a step of forming a slurry on a supporting substrate to form a ceramic green sheet, and applying laser to the supporting substrate and the ceramic green sheet from the supporting substrate side. Irradiating to form through holes, and filling the through holes with a conductive material from the support substrate side to form vias; peeling the support substrate from the ceramic green sheet; and Forming a conductive pattern constituting one coil on the upper and lower surfaces of the ceramic green sheet, and forming the ceramic green sheet by forming the slurry into a sheet shape on a support base. The thickness of the substrate is 1.0 to 2.0 times the thickness of the ceramic green sheet. Therefore, the thickness of the support base can be reduced, and this reduces the amount of conductive material that fills the through holes of the support base and constitutes the via. Therefore, when peeling the support base from the ceramic green sheet In addition, it is possible to prevent the conductive material constituting the vias of the ceramic green sheet from being taken to the support base side. As a result, it is possible to reduce the occurrence of defective continuity of the coil, and therefore, it is possible to improve the product yield.

  Hereinafter, a coil component according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view of a coil component according to an embodiment of the present invention, and FIG. 2 is an exploded perspective view of the coil component.

  As shown in FIGS. 1 and 2, the common mode noise filter which is a kind of coil component in one embodiment of the present invention includes first to fifth insulating layers 1 a to 1 e made of a magnetic or nonmagnetic material, The first to fourth insulating layers 1a to 1d are provided with first to fourth conductor patterns 2 to 5 provided in order on the respective upper surfaces, and these are integrated to form a laminate 6, and this The first to fourth external electrodes 7 a to 7 d are formed at both ends of the multilayer body 6.

  Furthermore, the first via 8a is formed in the second insulating layer 1b, the second via 8b is formed in the fourth insulating layer 1d, and the first conductor pattern is formed via the first via 8a. 2 and the second conductor pattern 3 are connected to provide the first coil 9, and the third conductor pattern 4 and the fourth conductor pattern 5 are connected via the second via 8b. Thus, the second coil 10 is provided. The first and second vias 8a and 8b are formed by the method described below.

  Further, the second conductor pattern 3 and the third conductor pattern 4 are opposed to each other through only the third insulating layer 1c, and the first conductor pattern 2 and the second conductor pattern 3 are magnetically coupled. Thus, common mode noise input to the first coil 9 and the second coil 10 can be removed.

  With the configuration described above, a common mode noise filter which is a kind of coil component according to an embodiment of the present invention is formed.

  Next, the manufacturing method of the common mode noise filter which is a kind of coil component in one embodiment of the present invention will be described.

  First, a ceramic green sheet is formed by adding an ester organic solvent and an alcohol organic solvent to a ceramic powder, adding a binder to a slurry kneaded by a ball mill, and applying the mixture onto a support substrate. This ceramic green sheet becomes the first to fifth insulating layers 1a to 1e shown in FIG.

  Hereinafter, the ceramic green sheets (second and fourth insulating layers 1b and 1d) on which the first and second vias 8a and 8b are formed will be mainly described.

  The relationship between the thickness of the ceramic green sheets constituting the second and fourth insulating layers 1b and 1d and the thickness of the support base on which the ceramic green sheets are formed is as follows. 0.0 times to 2.0 times.

  The support base is a film made of a resin such as polyethylene terephthalate (hereinafter referred to as “PET”) or polyethylene naphthalate. Among these, PET, which is easily available and inexpensive, is the support base. It is preferable as a material constituting

  Next, the support base and the ceramic green sheet are fixed to a metal frame, and laser is irradiated from the support base side to form through holes in the support base and the ceramic green sheet, respectively. The reason for irradiating the laser beam from the support substrate side is to increase the diameter of the via on the support substrate side and facilitate the printing of the conductive material from the support substrate side.

  Next, a paste-like conductive material made of silver or the like is printed from the support substrate side on the support substrate and the ceramic green sheet in which the through holes are respectively formed, and dried to fill the through holes with the conductive material. Second vias 8a and 8b are formed. The conductive material is printed from the support substrate side. When printing from the ceramic green sheet side, if the ceramic green sheet is peeled off or the conductive material remains on the ceramic green sheet, short circuit defects and delamination of the coil parts occur. Because.

  In this case, the diameter of the via in the ceramic green sheet is made smaller than the diameter of the via in the support base, and the difference is 55 μm or less.

  Next, the support base is peeled from the ceramic green sheet to obtain second and fourth insulating layers 1b and 1d. In parallel with this, the first, third, and fifth insulating layers 1a, 1c, and 1e are formed.

  Next, the ceramic green sheets (first to fifth insulating layers 1a to 1e) obtained as described above and the first to fourth conductor patterns 2 to 5 are laminated as shown in FIG. Thus, the laminated body 6 is formed. At this time, the first conductor pattern 2 and the second conductor pattern 3 constituting the first coil 9 are formed on the upper and lower surfaces of the ceramic green sheet (second insulating layer 1b) via the first via 8a. Then, the third conductor pattern 4 and the fourth conductor pattern 5 constituting the second coil 10 are formed on the upper and lower surfaces of the ceramic green sheet (fourth insulating layer 1d) through the second via 8b.

  Finally, the laminated body 6 is heated and pressurized, and the first to fourth external electrodes 7a to 7d are formed at both ends of the laminated body 6 to obtain a common mode noise filter which is a kind of coil component. It is what

  As described above, the method for manufacturing a coil component according to an embodiment of the present invention includes a step of forming a slurry on a supporting substrate to form a ceramic green sheet, and the supporting substrate and the ceramic green sheet supporting the supporting member. Forming through holes by irradiating laser from the substrate side, filling the through holes with a conductive material from the support substrate side to form vias, and peeling the support substrate from the ceramic green sheet And forming a conductive pattern constituting one coil on the upper and lower surfaces of the ceramic green sheet via the vias, and forming the ceramic green sheet by forming the slurry into a sheet shape on a supporting base. In the process, the thickness of the support base is 1.0 times to 2.0 times the thickness of the ceramic green sheet. Therefore, the thickness of the support base can be reduced, thereby reducing the amount of conductive material that fills the through holes of the support base and constitutes the via. When the support substrate is peeled off, the conductive material constituting the vias 8a and 8b of the ceramic green sheet can be prevented from being brought to the support substrate side. As a result, it is possible to reduce the occurrence of a coil conduction failure, so that the work can be easily performed and the yield of the product can be improved.

  Furthermore, the diameter of the via in the ceramic green sheet is made smaller than the diameter of the via in the support base and the difference is 55 μm or less, so that the amount of conductive material that fills the through hole of the support base and constitutes the via is reduced. As a result, when the support substrate is peeled off from the ceramic green sheet, it is possible to prevent the conductive material constituting the via of the ceramic green sheet from being taken to the support substrate side, thereby causing the occurrence of coil conduction failure. And the yield of products can be further improved.

  That is, as in the conventional case shown in FIG. 3A, the thickness of the support base made of PET film is much thicker than the thickness of the ceramic green sheet, and the via diameter in the support base is larger than the via diameter in the ceramic green sheet. However, when the support substrate is peeled off from the ceramic green sheet, the via may be brought back up because the amount of the conductive material that fills the through hole of the support substrate and forms the via increases. As in the embodiment of the present invention shown in FIG. 3B, the thickness of the support base is made to be 1.0 to 2.0 times the thickness of the ceramic green sheet. If the diameter of the via is made smaller than the diameter of the via in the supporting base and the difference is 55 μm or less, the conventional structure shown in FIG. Inconvenience is no longer so, is capable of improving the yield of products.

  Here, there are two main reasons why the vias are brought back as shown below. The first point is that more conductive material is filled in the via on the support base side than the via on the ceramic green sheet side. As a result, when the support substrate is peeled off from the ceramic green sheet, the conductive material on the ceramic base sheet side is carried by the conductive material on the support substrate side, so that the support substrate side is wiped with Ben cotton or the like soaked with an organic solvent. If complicated operations such as the above are not performed, the via is likely to be brought back.

  As a countermeasure, in one embodiment of the present invention, the thickness of the support base is 1.0 to 2.0 times the thickness of the ceramic green sheet. Here, when it is lower than 1.0 times, the thickness of the entire ceramic green sheet including the support base becomes too thin, and there is a problem in workability. On the other hand, if it is higher than 2.0 times, the vias are likely to be brought back unless a complicated operation such as wiping with a ben cotton soaked with an organic solvent from the support substrate side is performed.

  The second point is that the difference between the diameter of the via made of the conductive material in the ceramic green sheet and the diameter of the via made of the conductive material in the support base is larger than 55 μm. Since the through hole is formed by irradiating the laser from the support substrate side, the diameter of the via made of the conductive material in the ceramic green sheet is smaller than the diameter of the via made of the conductive material in the support substrate. When the difference between the diameter of the via made of the conductive material and the diameter of the via made of the conductive material in the support base is larger than 55 μm, the ceramic green sheet is used as the conductive material on the support base side when the support base is peeled off from the ceramic green sheet. Since the conductive material on the side is carried, if the troublesome operation such as wiping with Ben cotton soaked with an organic solvent is not performed from the support base side, the via is likely to be brought back like the first point.

  (Table 1) shows a comparison between one embodiment of the present invention and a conventional example regarding the relationship between the manufacturing conditions, the via diameter, and whether or not the via is brought back. A PET film was used as the support base, and a common mode noise filter shown in FIGS. 1 and 2 was used as the coil component.

  As is clear from (Table 1), when the difference between the diameter of the via in the ceramic green sheet and the diameter of the via in the support substrate is 55 μm or less, the via does not turn over.

  In the coil component according to the embodiment of the present invention, a common mode noise filter which is a kind of coil component has been described as an example. However, even when applied to other coil components such as multilayer chip beads, The same effects as those of the embodiment of the present invention can be obtained.

  The method of manufacturing a coil component according to the present invention has an effect that the work can be easily performed and the yield of the product can be improved. In particular, noise countermeasures for various electronic devices such as digital devices, AV devices, and information communication terminals are provided. It is useful in coil parts used as

The perspective view of the common mode noise filter in one embodiment of this invention Exploded perspective view of the common mode noise filter (A) Schematic diagram of a cross section showing a state at the time of forming a through hole in a conventional common mode noise filter, (b) Schematic cross section showing a state at the time of forming a through hole in a common mode noise filter in one embodiment of the present invention. Figure

Explanation of symbols

2-5 1st-4th conductor pattern 8a, 8b Via 9 1st coil 10 2nd coil

Claims (2)

A step of preparing a slurry by mixing ceramic powder, a binder and an organic solvent, a step of forming this slurry into a sheet form on a support substrate to form a ceramic green sheet, and the support on the support substrate and the ceramic green sheet Forming through holes by irradiating laser from the substrate side, filling the through holes with a conductive material from the support substrate side to form vias, and peeling the support substrate from the ceramic green sheet And forming a conductive pattern constituting one coil on the upper and lower surfaces of the ceramic green sheet via the vias, and forming the ceramic green sheet by forming the slurry into a sheet shape on a supporting base. In the step, the thickness of the support substrate is 1 of the thickness of the ceramic green sheet. 0 to 2.0 times to become like the manufacturing method of the coil component you. The method for manufacturing a coil component according to claim 1, wherein the diameter of the via in the ceramic green sheet is made smaller than the diameter of the via in the support base, and the difference is 55 µm or less.

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