JP2012004180A - Manufacturing method of ceramic electronic component - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a manufacturing method of a ceramic electronic component capable of manufacturing the ceramic electronic component having a small height dimension with high shape accuracy.SOLUTION: A plurality of holes 22a are formed by the irradiation of laser light on a cutting line of an unsintered ceramic mother block 22. Conductive paste is coated on the unsintered ceramic mother block 22 having the plurality of holes 22a formed thereon. By cutting the unsintered ceramic mother block 22 having the coated conductive paste into a plurality of portions on the cutting line, a plurality of unsintered ceramic elements 24 are manufactured. By sintering the plurality of unsintered ceramic elements 24, a plurality of ceramic electronic components 1 are manufactured.

Description

  The present invention relates to a method for manufacturing a ceramic electronic component. In particular, the present invention relates to a method of manufacturing a ceramic electronic component in which at least a part of an external electrode is co-fired with a ceramic body including the internal electrode, that is, formed by a cofire.

  In recent years, various ceramic electronic components such as ceramic capacitors have been increasingly used in various electronic devices because of their small size and high functionality.

  FIG. 18 shows a schematic cross-sectional view of a conventional ceramic capacitor 100. As shown in FIG. 18, the ceramic capacitor 100 includes a rectangular parallelepiped ceramic body 101. Inside the ceramic body 101, first and second internal electrodes 102 and 103 are formed. On the surface of the ceramic body 101, first and second external electrodes 104 and 105 that are electrically connected to the first or second internal electrodes 102 and 103 are formed. The first and second external electrodes 104 and 105 are respectively provided with first and second portions 104a, 105a, and 104b formed on the first or second main surface 101a and 101b of the ceramic body 101. , 105b and third portions 104c, 105c formed on the first or second end face 101c, 101d.

  In general, the first and second external electrodes 104 and 105 include a base electrode layer formed on the ceramic body 101 and one or a plurality of plating layers formed on the base electrode layer. And have. Among these, as a method for forming the base electrode layer, a dip method in which the conductive paste is applied by being immersed in the conductive paste is generally used.

  However, when the base electrode layer is formed by the dipping method, the base electrode layer has a rounded shape due to the surface tension of the conductive paste. Therefore, in the ground electrode layer, the portions located on the corner portions and the ridge line portions are thinner than the portions located on the main surfaces 101a and 101b and the side surfaces 101c and 101d. For this reason, if the coating thickness is too thin, the base electrode layer may not be suitably formed on the corners or ridges of the ceramic body 101. For this reason, it is necessary to form the base electrode layer thickly so that the base electrode layer is suitably formed also on the corners and ridges of the ceramic body 101. However, in this case, since the thickness h101 of the portion of the base electrode layer located on the main surfaces 101a and 101b is increased, the thickness h100 of the entire ceramic capacitor 100 is also increased, and the ceramic capacitor 100 is reduced in height. There is a problem that it is difficult. Further, there is a problem that a distance (hereinafter referred to as “stand-off”) between the mounting substrate and the ceramic body 101 when the ceramic capacitor 100 is mounted on the mounting substrate is increased.

  As another method of forming the external electrode, for example, as described in Patent Document 1 below, a conductive paste is applied to the surface of the raw mother block, and firing, cutting of the mother block, and the like are appropriately performed. A method for forming an external electrode is known. According to this method, the thickness of the portion of the external electrode located on the main surface of the ceramic body can be reduced. Therefore, it is possible to obtain a ceramic electronic component that is low in profile and that can shorten the stand-off.

Japanese Patent Laid-Open No. 6-112199

  However, the unfired raw mother block is softer and more easily deformed than the fired mother block. For this reason, when an external electrode is formed by applying a conductive paste using various printing methods such as a screen printing method, the mother block may be deformed by pressing the mother block with a squeegee or the like. When the mother block is deformed, the printing accuracy may be lowered, or the shape of the coating film may be deteriorated. Therefore, it is difficult to produce a ceramic electronic component with high shape accuracy.

  This invention is made | formed in view of this point, The objective is to provide the manufacturing method of the ceramic electronic component which can manufacture a ceramic electronic component with a small height dimension with high shape accuracy.

  The method for manufacturing a ceramic electronic component according to the present invention relates to a method for manufacturing a ceramic electronic component having a ceramic element body and external electrodes formed on the surface of the ceramic element body. The method for manufacturing a ceramic electronic component according to the present invention includes first to third steps. The first step is a step of forming a plurality of holes by irradiating a laser beam on a cutting line of an unfired ceramic mother block. The second step is a step of applying a conductive paste on an unfired ceramic mother block in which a plurality of holes are formed. The third step is to produce a plurality of unfired ceramic elements by dividing the unfired ceramic mother block coated with the conductive paste into a plurality of parts in the cutting line. This is a step of producing a plurality of ceramic electronic components by firing the body.

  In the present invention, the “cutting line” is a line to be divided in the third step, and is a virtual line.

  In a specific aspect of the method for manufacturing a ceramic electronic component according to the present invention, a cutting line is specified by using a plurality of holes as alignment marks, and a plurality of unfired ceramic mother blocks are provided by the specified cutting line. Divide. In this case, since it is not necessary to separately form an alignment mark for specifying the cutting line, it is easy to manufacture a ceramic electronic component. Moreover, the ceramic mother block can be divided with high accuracy.

  In another specific aspect of the method of manufacturing a ceramic electronic component according to the present invention, the green ceramic mother block is divided into a plurality of pieces by dicing so that the plurality of holes are removed. In this case, the wall part which has formed the hole in the manufactured ceramic electronic component does not remain. Moreover, since the wall part which comprised the void | hole before the baking process is removed, the part from which rigidity differs from another part is lose | eliminated. Therefore, internal stress is unlikely to occur in the firing process, and structural defects and the like can be suppressed from being produced in the manufactured ceramic electronic component.

  In still another specific aspect of the method for manufacturing a ceramic electronic component according to the present invention, the cutting line includes a plurality of first cutting lines along the first direction and a second perpendicular to the first direction. A plurality of second cutting lines along the direction are included, and at least one of the plurality of holes is formed on an intersection of the first cutting line and the second cutting line. In this case, it is presumed that hard hole wall portions are formed at the corner portions of the unfired ceramic body. For this reason, it is estimated that the deformation | transformation of the ceramic mother block in an application | coating process can be suppressed more suitably.

  In still another specific aspect of the method for manufacturing a ceramic electronic component according to the present invention, the ceramic mother block is pressed after the second step and before the third step. When pressing an unfired ceramic mother block as in this case, the ceramic mother block is easily deformed in the pressing step. However, in the present invention, it is presumed that the deformation of the ceramic mother block is suitably suppressed by the wall portion of the hard hole. Therefore, a ceramic electronic component can be manufactured with high shape accuracy.

  In the present invention, the external electrode is formed by applying a conductive paste on both main surfaces of the unfired ceramic mother block. For this reason, for example, the external electrode can be formed thinner than the case where the external electrode is formed by the dipping method. Therefore, a ceramic electronic component having a small height can be manufactured. Moreover, in this invention, a void | hole is formed by irradiation of a laser beam before application | coating of an electrically conductive paste. Here, the wall portion of the hole is harder than the other portion of the ceramic mother block by the laser beam. Therefore, it is presumed that the wall portion of the hole functions as a support portion, and the ceramic mother block is hardly deformed even when pressure is applied to the ceramic mother block during application of the conductive paste. As a result, the ceramic electronic component can be manufactured with high shape accuracy.

1 is a schematic perspective view of a ceramic electronic component according to a first embodiment. 1 is a schematic side view of a ceramic electronic component according to a first embodiment. FIG. 3 is a schematic cross-sectional view taken along line III-III in FIG. 1. FIG. 4 is a schematic cross-sectional view taken along line IV-IV in FIG. 3. FIG. 4 is a schematic cross-sectional view in which a portion surrounded by a line V in FIG. 3 is enlarged. It is a schematic plan view of a ceramic green sheet on which a conductive pattern is formed. It is a schematic plan view of a ceramic mother block. It is a schematic plan view of a ceramic mother block on which a conductive pattern for forming the first or second portion of the external electrode is formed. It is a schematic plan view of an unfired ceramic body. FIG. 10 is a schematic side view of the ceramic body viewed from a direction X in FIG. 9. FIGS. 11A to 11C are schematic side views for explaining a conductive pattern forming process for forming the third portion of the first and second external electrodes. It is a schematic sectional drawing of the ceramic electronic component which concerns on 2nd Embodiment. It is a schematic sectional drawing of the ceramic electronic component which concerns on 3rd Embodiment. FIG. 10 is a schematic plan view of a ceramic mother block in which a conductive pattern for forming a first or second portion of an external electrode is formed in a fourth embodiment. FIG. 10 is a schematic plan view of a ceramic mother block on which a conductive pattern for forming a first or second portion of an external electrode is formed in a fifth embodiment. It is a schematic top view of the ceramic electronic component produced in 6th Embodiment. It is a schematic plan view of the ceramic mother block produced in the Example. It is a schematic sectional drawing of the conventional ceramic capacitor.

  Hereinafter, an example of a preferable embodiment of the present invention will be described. However, the following embodiments are merely examples. The present invention is not limited to the following embodiments.

(First embodiment)
FIG. 1 is a schematic perspective view of the ceramic electronic component according to the first embodiment. FIG. 2 is a schematic side view of the ceramic electronic component according to the first embodiment. 3 is a schematic cross-sectional view taken along line III-III in FIG. 4 is a schematic cross-sectional view taken along line IV-IV in FIG. FIG. 5 is a schematic cross-sectional view in which a portion surrounded by a line V in FIG. 3 is enlarged.

  First, the structure of the ceramic electronic component 1 manufactured in the present embodiment will be described with reference to FIGS.

  As shown in FIGS. 1 to 4, the ceramic electronic component 1 includes a ceramic body 10. The ceramic body 10 is made of an appropriate ceramic material corresponding to the function of the ceramic electronic component 1.

Specifically, when the ceramic electronic component 1 is a capacitor, the ceramic body 10 can be formed of a dielectric ceramic material. Specific examples of the dielectric ceramic material include BaTiO ₃ , CaTiO ₃ , SrTiO ₃ , CaZrO _{3 and the} like. In addition to the ceramic material, the ceramic body 10 includes, for example, a Mn compound, a Mg compound, a Si compound, a Fe compound, a Cr compound, a Co compound, a Ni compound, according to the desired characteristics of the ceramic electronic component 1. Subcomponents such as rare earth compounds may be added as appropriate.

  When the ceramic electronic component 1 is a ceramic piezoelectric element, the ceramic body 10 can be formed of a piezoelectric ceramic material. Specific examples of the piezoelectric ceramic material include a PZT (lead zirconate titanate) ceramic material.

  When the ceramic electronic component 1 is a thermistor element, the ceramic body 10 can be formed of a semiconductor ceramic material. Specific examples of the semiconductor ceramic material include spinel ceramic materials.

  When the ceramic electronic component 1 is an inductor element, the ceramic body 10 can be formed of a magnetic ceramic material. Specific examples of the magnetic ceramic material include a ferrite ceramic material.

  The shape of the ceramic body 10 is not particularly limited. In the present embodiment, the ceramic body 10 is formed in a rectangular parallelepiped shape. As shown in FIGS. 1 to 3, the ceramic body 10 has first and second main surfaces 10 a and 10 b extending along the length direction L and the width direction W. The ceramic body 10 includes first and second side surfaces 10c and 10d extending along the height direction H and the length direction L, as shown in FIGS. Moreover, as shown in FIGS. 2-4, the 1st and 2nd end surface 10e, 10f extended along the height direction H and the width direction W is provided.

  In the present specification, the “cuboid” includes a rectangular parallelepiped whose corners and ridges are chamfered or rounded. That is, the “cuboid” member means all members having first and second main surfaces, first and second side surfaces, and first and second end surfaces. Moreover, unevenness etc. may be formed in a part or all of a main surface, a side surface, and an end surface.

  The dimensions of the ceramic body 10 are not particularly limited. For example, the height dimension, the length dimension, and the width dimension of the ceramic body 10 are 0.1 μm to 0.4 μm, 0.4 μm to 1.0 μm, It can be about 0.2 μm to 0.5 μm. In the present embodiment, the length dimension, the width dimension, and the height dimension of the ceramic body 10 satisfy the relationship of (length dimension)> (width dimension)> (height dimension). Specifically, the length dimension, the width dimension, and the height dimension of the ceramic body 10 satisfy the relationship of 1/5 (width dimension) ≦ (height dimension) ≦ 2/3 (length dimension).

  As shown in FIGS. 3 and 4, a plurality of substantially rectangular first and second inner electrodes 11 and 12 are alternately arranged along the height direction H at equal intervals in the ceramic body 10. Has been. Each of the first and second internal electrodes 11 and 12 is parallel to the first and second main surfaces 10a and 10b. The first and second internal electrodes 11 and 12 face each other in the height direction H via the ceramic layer 10g shown in FIG.

  The thickness of the ceramic layer 10g is not particularly limited. The thickness of the ceramic layer 10g can be, for example, about 0.5 μm to 5.0 μm. The thickness of each of the first and second internal electrodes 11 and 12 is not particularly limited. Each thickness of the 1st and 2nd internal electrodes 11 and 12 can be about 0.5 micrometer-2 micrometers, for example.

  The first and second internal electrodes 11 and 12 can be formed of an appropriate conductive material. The first and second internal electrodes 11 and 12 may be formed of, for example, a metal such as Ni, Cu, Ag, Pd, or Au, or an alloy containing one or more of these metals such as an Ag—Pd alloy. it can.

  As shown in FIGS. 1 to 4, first and second external electrodes 13 and 14 are formed on the surface of the ceramic body 10. The first external electrode 13 is electrically connected to the first internal electrode 11. The first external electrode 13 includes a first portion 13a formed on the first main surface 10a, a second portion 13b formed on the second main surface 10b, And a third portion 13c formed on the end face 10e. In the present embodiment, the first external electrode 13 is not substantially formed on the first and second side surfaces 10c, 10d. However, in the present invention, the first external electrode may also be formed on the first and second side surfaces.

  On the other hand, the second external electrode 14 is electrically connected to the second internal electrode 12. The second external electrode 14 includes a first portion 14a formed on the first main surface 10a, a second portion 14b formed on the second main surface 10b, and a second portion And a third portion 14c formed on the end face 10f. In the present embodiment, the second external electrode 14 is not substantially formed on the first and second side surfaces 10c, 10d. However, in the present invention, the second external electrode may also be formed on the first and second side surfaces.

  As shown in FIG. 5, each of the first and second external electrodes 13 and 14 is configured by a laminated body of a base electrode layer 15 and first and second plating layers 16 and 17. The base electrode layer 15 is formed on the ceramic body 10. The first plating layer 16 is formed on the base electrode layer 15. The second plating layer 17 is formed on the first plating layer 16.

  The base electrode layer 15 preferably includes, for example, a conductive material and an inorganic binder. By including an inorganic binder in the base electrode layer 15, the adhesion strength between the base electrode layer 15 and the ceramic body 10 can be increased. Further, by including a conductive material in the base electrode layer 15, the adhesion strength between the base electrode layer 15 and the first plating layer 16 can be increased. Specific examples of the inorganic binder include a ceramic material and a glass component that are the same type as the ceramic material included in the ceramic body 10. Specific examples of the conductive material include metals such as Ni, Cu, Ag, Pd, and Au, and alloys including one or more of these metals such as an Ag—Pd alloy.

  Each of the first and second plating layers 16 and 17 is made of, for example, a metal such as Ni, Cu, Ag, Pd, or Au, or an alloy containing one or more of these metals such as an Ag—Pd alloy. It is preferable that Each thickness of the 1st and 2nd plating layers 16 and 17 can be about 1 micrometer-10 micrometers, for example.

  In addition, although this embodiment demonstrates the example which forms the 1st and 2nd plating layers 16 and 17, this invention is not limited to this structure. For example, the external electrode may be composed only of the base electrode layer. Further, one or three or more plating layers may be provided on the base electrode layer.

  The maximum thickness of the base electrode layer 15 can be, for example, about 5 μm to 30 μm. The maximum thickness of the first plating layer 16 is preferably about 1 μm to 10 μm, for example. The maximum thickness of the second plating layer 17 is preferably about 1 μm to 10 μm, for example.

  Next, the manufacturing method of the ceramic electronic component 1 in this embodiment is demonstrated.

  First, a ceramic mother block (see FIG. 7) is manufactured. Specifically, first, a ceramic green sheet 20 (see FIG. 6) including a ceramic material for constituting the ceramic body 10 is prepared. The ceramic green sheet 20 can be produced by forming a ceramic slurry obtained by mixing ceramic powder, an organic binder, an organic solvent, and the like into a sheet shape. In addition, as an organic binder, polyvinyl alcohol (PVA), polyvinyl butyral (PVB), etc. can be used, for example. For example, toluene or xylene can be used as the organic solvent. The ceramic green sheet 20 is preferably produced so as to have a thickness of about 0.5 μm to 5.0 μm after firing.

  Next, as shown in FIG. 7, a conductive pattern 21 for forming the internal electrodes 11 and 12 is formed on the ceramic green sheet 20 by applying a conductive paste. The conductive pattern can be applied by various printing methods such as a screen printing method. The conductive paste may contain a known binder or solvent in addition to the conductive fine particles. As the conductive fine particles, for example, fine particles made of a metal such as Ni, Cu, Ag, Pd, or Au, or an alloy containing one or more of these metals such as an Ag—Pd alloy can be used. As the organic binder, for example, polyvinyl alcohol (PVA), polyvinyl butyral (PVB), or the like can be used. For example, toluene or xylene can be used as the organic solvent. The conductive pattern 21 is preferably formed such that the thickness after firing (that is, the thickness of the internal electrodes 11 and 12) is about 0.5 μm to 2.0 μm.

  Next, a plurality of ceramic green sheets 20 in which the conductive pattern 21 is not formed, a ceramic green sheet 20 in which the conductive pattern 21 is formed, and a plurality of ceramic green sheets 20 in which the conductive pattern 21 is not formed are The ceramic mother block 22 shown in FIG. 7 is produced by laminating in order and pressing the hydrostatic pressure in the laminating direction as necessary.

  Next, the unfired ceramic mother block 22 is irradiated with laser light to form a plurality of holes 22a penetrating the ceramic mother block 22 in the height direction H (first step).

  Specifically, in the present embodiment, a plurality of first cutting lines L1 along the length direction L and a plurality of second cutting lines L2 along the width direction W perpendicular to the length direction L. A hole 22a is formed at each of the plurality of intersections.

  The shape dimension and quantity of the air holes 22a to be formed can be set as appropriate according to the quantity of ceramic electronic components produced from one ceramic mother block 22, the shape dimension of the ceramic mother block 22, and the like. The shape of the air holes 22a is preferably, for example, a cylindrical shape or a polygonal column shape. When the hole 22a is cylindrical, the diameter of the hole 22a is preferably about 100 μm to 200 μm.

  In the present embodiment, an example in which the air holes 22a are formed so as to penetrate the ceramic mother block 22 in the height direction H will be described, but the present invention is not limited to this. For example, the air holes 22a may be formed so as not to penetrate the ceramic mother block 22 in the height direction H. In that case, a hole extending from one main surface side of the ceramic mother block 22 toward the other main surface side and a hole extending from the other main surface side toward the one main surface side are formed. Is preferred.

The laser used for forming the air holes 22a can be appropriately selected according to the type of the ceramic mother block 22 and the like. Specific examples of the laser used for forming the air holes 22a include a CO ₂ laser and an excimer laser.

  Next, as shown in FIG. 8, by applying a conductive paste on both main surfaces of the ceramic mother block 22 in which a plurality of holes 22a are formed, the first and second external electrodes 13, A conductive pattern 23 for forming the first and second portions 13a, 14a, 13b, and 14b of the fourteen is formed (second step). This conductive paste preferably contains the above-described conductive fine particles and an inorganic binder.

  The conductive paste can be applied by various printing methods such as a screen printing method.

  In the present embodiment, the holes 22a formed as described above are used as alignment marks when applying the conductive paste. That is, the position of the hole 22a is detected, and the conductive paste is applied based on the detection result. Therefore, it is not necessary to separately form an alignment mark when applying the conductive paste, and the conductive pattern 23 can be printed with higher positional accuracy.

  The conductive pattern 23 is preferably formed so that the thickness after firing is about 5.0 μm to 15.0 μm.

  Next, the green ceramic mother block 22 on which the conductive pattern 23 is formed is divided by a plurality of first and second cutting lines L1 and L2, so that a plurality of green ceramic bodies are removed from the ceramic mother block 22. 24 (see FIG. 9) is produced. The ceramic mother block 22 can be divided by, for example, dicing. When the ceramic mother block 22 is divided, the ceramic mother block 22 is preferably diced so that the holes 22a are removed. Specifically, it is preferable to divide the ceramic mother block 22 and remove the holes 22a by dicing using a dicing blade having a width equal to or larger than the diameter R (see FIG. 8) of the holes 22a. By doing so, it is possible to prevent traces of the holes 22a from remaining in the manufactured ceramic electronic component 1.

  Since the ridges and corners of the ceramic body 24 formed by dicing are sharp, for example, by performing polishing such as barrel polishing, the ridges of the ceramic body 24 are shown in FIGS. 9 and 10. It is preferable to chamfer or round the corners. Further, in this polishing step, even if a part of the wall portion of the hole 22a remains, the remaining wall portion is removed.

  In the present embodiment, the holes 22a are also used as alignment marks in the process of dividing the ceramic mother block 22. That is, the first and second cutting lines L1 and L2 (dividing positions) are identified by detecting the holes 22a, and the ceramic mother block 22 is divided into a plurality of parts by the first and second cutting lines L1 and L2. To do. By doing so, it is not necessary to separately form an alignment mark for dividing the ceramic mother block 22, and the ceramic mother block 22 can be divided with high accuracy. Therefore, the ceramic electronic component 1 with high shape accuracy can be manufactured.

  As shown in FIG. 10, the third portions 13 c and 14 c of the first and second external electrodes 13 and 14 are formed on the end surface of the ceramic body 24 immediately after being separated from the ceramic mother block 22. A conductive pattern is not formed. Therefore, next, a conductive pattern for forming the third portions 13c and 14c of the first and second external electrodes 13 and 14 is formed.

  Specifically, as shown in FIGS. 11A to 11C, the end surfaces 24 a and 24 b of the ceramic body 24 are sequentially immersed in the conductive paste 26 and pulled up to form the conductive pattern 25. It should be noted that the conductive paste 26 applied to the end faces 24 a and 24 b is sufficient to cover the end faces 24 a and 24 b and be connected to the conductive pattern 23. The conductive pattern 25 is preferably formed to a thickness such that the thickness after firing is about 5.0 μm to 30.0 μm.

  Note that the conductive paste 26 may slightly wrap around the side surface of the ceramic body 24 at the time of immersion. As the conductive paste 26, the same paste as that used for forming the conductive pattern 23 can be used.

  Next, the ceramic body 24 in which the conductive patterns 25 are formed on both the end faces 24a and 24b is fired. Thereby, the fired ceramic body 10 is formed from the unfired ceramic body 24, and the first and second internal electrodes 11, 12 and the first and second external electrodes are formed from the conductive patterns 21, 23, 25. 13, 14 base electrode layers 15 can be formed.

  The firing temperature and firing time can be appropriately set depending on the ceramic material and conductive material used. The firing temperature can be, for example, about 900 ° C. to 1300 ° C.

  Alternatively, baking may be performed without forming the conductive pattern 25, and then the third portions 13c and 14c of the first and second external electrodes 13 and 14 may be formed.

  Finally, the first and second plating layers 16 and 17 are formed to complete the ceramic electronic component 1.

  By the way, for example, when applying the conductive paste by the screen printing method, the conductive paste is applied by supplying the conductive paste onto the ceramic mother block 22 and moving it while pressing the squeegee. Therefore, stress is applied to the ceramic mother block 22 in the conductive paste application step. For this reason, there is a possibility that the unfired ceramic mother block 22 is deformed.

  However, in the present embodiment, as described above, the holes 22a are formed by irradiating laser light. For this reason, the part which comprises the wall part of the hole 22a among the ceramic mother blocks 22 denatures with the irradiated laser beam, and becomes higher rigidity than other parts. Therefore, the wall portion of the highly rigid hole 22a functions as a support portion, and it is estimated that the ceramic mother block 22 is not easily deformed even when stress is applied to the ceramic mother block 22. Therefore, the ceramic electronic component 1 can be manufactured with high shape accuracy.

  In the present embodiment, the portions constituting the first and second portions 13a, 13b, 14a and 14b of the base electrode layer 15 of the first and second external electrodes 13 and 14 are coated with conductive paste. And a cofire. Therefore, the thickness of the portions constituting the first and second portions 13a, 13b, 14a, 14b of the base electrode layer 15 can be reduced. As a result, the ceramic electronic component 1 having a small height can be manufactured.

  In the present embodiment, the holes 22 a are used as alignment marks when applying the conductive paste or dividing the ceramic mother block 22. For this reason, it is not necessary to form an alignment mark separately. Therefore, the manufacturing process of the ceramic electronic component 1 can be simplified. Furthermore, the ceramic electronic component 1 having high shape accuracy can be manufactured.

  In addition, since the ceramic electronic component 1 is manufactured using the ceramic mother block 22, a plurality of ceramic electronic components 1 can be manufactured in parallel. Therefore, the ceramic electronic component 1 can be manufactured with high productivity.

  The wall portion of the hole 22a may remain in the ceramic electronic component 1. However, when the wall portion of the hard hole 22a remains in the ceramic electronic component 1, internal stress is likely to occur. There is a risk of causing structural defects such as delamination in the firing process. Therefore, it is preferable to remove the wall portions of the air holes 22a in a dicing process or the like as in the present embodiment.

  Hereinafter, other examples of preferred embodiments of the present invention will be described. In the following description of the embodiment, members having substantially the same functions as those of the first embodiment are referred to by common reference numerals, and description thereof is omitted.

(Second Embodiment)
FIG. 12 is a schematic cross-sectional view of a ceramic electronic component according to the second embodiment.

  In the first embodiment, a portion of the first and second main surfaces 10a and 10b where the first or second external electrodes 13 and 14 are formed, and the first or second external electrode 13 are formed. The example in which the base electrode layer 15 is formed so as to be flush with the portion where the. However, the present invention is not limited to this configuration. Of the first and second main surfaces 10a and 10b, a portion where the first or second external electrode 13, 14 is formed and a portion where the first or second external electrode 13, 14 is not formed May not be formed flush with each other.

  For example, as shown in FIG. 12, a portion of the first and second main surfaces 10a and 10b where the first or second external electrodes 13 and 14 are formed is the first or second external electrode. The base electrode layer 15 may be formed so as to be located on the inner side in the height direction H than the portion where the 13 and 14 are not formed. By doing so, the ceramic electronic component 1 can be further reduced in height.

  As a method of embedding a part of the base electrode layer 15 in the first and second main surfaces 10a and 10b as in the present embodiment, the ceramic mother block 22 is formed after the conductive pattern 23 (see FIG. 8) is formed. The method of pressing is mentioned. As described above, when the ceramic mother block 22 is pressed after the conductive pattern 23 is formed, the ceramic mother block 22 may be deformed in this pressing process. Therefore, the ceramic mother block 22 is deformed by forming the holes 22a. The technique of the present embodiment, which is estimated to be able to be suppressed, is particularly effective.

(Third embodiment)
FIG. 13 is a schematic cross-sectional view of a ceramic electronic component according to the third embodiment.

  In the first embodiment, the example in which the first and second external electrodes 13 and 14 are formed on both the first and second main surfaces 10a and 10b has been described. However, the present invention is not limited to this configuration.

  For example, as shown in FIG. 13, the first and second external electrodes 13 and 14 are formed only on the second main surface 10b of the first and second main surfaces 10a and 10b, respectively. May be. Thus, the ceramic electronic component 1 can be easily mounted by forming each of the first and second external electrodes 13 and 14 on at least one of the first and second main surfaces 10a and 10b. Can increase the sex.

  Further, each of the first and second external electrodes 13 and 14 is formed only on the second main surface 10b of the first and second main surfaces 10a and 10b, thereby further reducing the height. The ceramic electronic component 1 can be manufactured.

(Fourth and fifth embodiments)
FIG. 14 is a schematic plan view of a ceramic mother block on which a conductive pattern for forming the first or second portion of the external electrode is formed in the fourth embodiment. FIG. 15 is a schematic plan view of a ceramic mother block in which a conductive pattern for forming the first or second portion of the external electrode is formed in the fifth embodiment.

  In the first embodiment, the example in which the hole 22a is formed on each of the plurality of intersections of the first cutting line L1 and the second cutting line L2 has been described. However, the present invention is not limited to this configuration.

  For example, when it is desired to suppress the deformation of the ceramic mother block 22 more effectively, as shown in FIG. 14, a hole 22a is formed at the intersection of the first cutting line L1 and the second cutting line L2. The air holes 22a may also be formed on portions other than the intersections of the first or second cutting lines L1 and L2. In particular, it is preferable to form a further hole 22a on the longer one between the intersections of the first and second cutting lines L1, L2.

  Further, for example, when it is difficult for deformation of the ceramic mother block 22, as shown in FIG. 15, an empty space is formed on a part of a plurality of intersections of the first cutting line L1 and the second cutting line L2. The hole 22a may be formed. By doing so, the quantity of the holes 22a can be reduced, the manufacturing process can be simplified, and the time required for manufacturing can be shortened.

(Sixth embodiment)
FIG. 16 is a schematic plan view of a ceramic electronic component manufactured in the sixth embodiment.

  In the first embodiment, the example in which the hole 22a is removed by dicing so that the wall portion of the hole 22a does not remain in the ceramic electronic component has been described. However, the present invention is not limited to this.

  For example, by making the width of the dicing blade used for dividing the ceramic mother block 22 smaller than the diameter of the hole 22a, the wall portion of the hole 22a remains in the cutting step of the ceramic mother block 22. Also good. In this case, as shown in FIG. 16, the ceramic electronic component 1 is formed with recesses 40 that are recessed toward the center on the four ridge lines extending along the height direction H.

(Example)
In this example, a ceramic electronic component having a configuration substantially similar to that of the ceramic electronic component 1 described in the first embodiment was manufactured in the following manner.

A 1.4 μm thick ceramic green sheet containing a BaTiO ₃ ceramic and an internal electrode Ni paste were prepared. A conductive pattern for forming internal electrodes was formed by printing Ni paste in a predetermined pattern on the ceramic green sheet. The thickness of the conductive pattern was 0.5 μm.

  Next, a plurality of ceramic green sheets on which no conductive pattern is formed, a plurality of ceramic green sheets on which the conductive pattern is formed, and a plurality of ceramic green sheets on which no conductive pattern is formed are appropriately laminated in this order. Then, the ceramic mother block 22 (see FIG. 17) was produced by hydrostatic pressure pressing.

Next, a CO ₂ laser (ML605GTX manufactured by Mitsubishi Electric Corporation) was irradiated from one main surface of the ceramic mother block 22 to form a plurality of holes 22a penetrating the ceramic mother block 22 from one main surface to the other main surface. As shown in FIG. 17, the air holes 22a were formed at the intersections of the first cutting line L1 and the second cutting line L2. The diameter of the air holes 22a was 200 μm.

  Next, an external electrode Ni paste is prepared and printed on both main surfaces of the ceramic mother block by screen printing in a predetermined pattern to form the conductive pattern 23 for forming the external electrode, and the reference marks 41a and 41b are formed. , Both ends in the width direction W and formed in the center in the length direction L. Note that the distance Y between the centers of the reference marks 41a and 41b immediately after the formation was 159 μm.

  Thereafter, a second hydrostatic pressure press was performed.

  Next, a plurality of raw ceramic bodies were prepared by dividing the ceramic mother block 22 into a plurality of pieces by dicing. In addition, since the dicing blade thicker than the diameter of the hole 22a was used at the time of dicing, the hole 22a was removed.

  Next, Ni paste for external electrodes was applied to both end faces of the raw ceramic body in the manner described in the first embodiment.

  Next, the raw ceramic body was fired under conditions of a maximum temperature of 1200 ° C. and a maximum temperature holding time: 2 hours, and a nitrogen gas atmosphere.

  Thereafter, Cu plating was performed on the base electrode layer formed on the ceramic body to complete the external electrode. The dimensions of the produced ceramic electronic component (multilayer ceramic capacitor) were 1.00 mm × 0.50 mm × 0.15 mm.

(Comparative example)
In this comparative example, a ceramic electronic component was produced in the same manner as in the above example except that the holes 22a were not formed.

(Evaluation)
In each of the above examples and comparative examples, the center-to-center distance Y between the reference marks 41a and 41b is set immediately before the formation of the conductive pattern 23 after the formation of the conductive pattern 23 for forming the external electrode and after the second isostatic pressing. The amount of change was measured. As a result, the amount of change in the center-to-center distance Y was smaller in the example than in the comparative example.

DESCRIPTION OF SYMBOLS 1 ... Ceramic electronic component 10 ... Ceramic body 10a ... 1st main surface 10b of a ceramic body ... 2nd main surface 10c of a ceramic body ... 1st side 10d of a ceramic body ... 2nd of a ceramic body Side surface 10e of the ceramic body First end surface 10f of the ceramic body Second end surface 10g of the ceramic body Ceramic layer 11 First internal electrode 12 Second internal electrode 13 First external electrode 13a First 1st part 13b of 1st external electrode ... 2nd part 13c of 1st external electrode ... 3rd part 14 of 1st external electrode ... 2nd external electrode 14a ... 1st of 2nd external electrode Part 14b ... Second part 14c of the second external electrode ... Third part 15 of the second external electrode ... Base electrode layer 16 ... First plating layer 17 ... Second plating layer 20 ... Ceramic green sheet 21 ... Conductive pattern 22 ... Ceramic Kumaser block 22a ... hole 23 ... conductive pattern 24 ... unfired ceramic body 24a, 24b ... end face 25 of ceramic body ... conductive pattern 26 ... conductive paste 40 ... recessed portion 41a, 41b ... reference mark L1 ... first Cutting line L2 ... the second cutting line

Claims (5)

A ceramic electronic component manufacturing method comprising a ceramic body and an external electrode formed on a surface of the ceramic body,
A first step of forming a plurality of holes by irradiating a laser beam on a cutting line of an unfired ceramic mother block;
A second step of applying a conductive paste on the unfired ceramic mother block in which the plurality of holes are formed;
A plurality of unfired ceramic bodies are produced by dividing the unfired ceramic mother block coated with the conductive paste into a plurality of portions in the cutting line, and firing the plurality of unfired ceramic bodies. And a third step of producing a plurality of the ceramic electronic components.   2. The manufacturing of a ceramic electronic component according to claim 1, wherein the plurality of holes are used as alignment marks to identify the cutting line, and the green ceramic mother block is divided into a plurality of parts by the identified cutting line. 3. Method.   The method for manufacturing a ceramic electronic component according to claim 1, wherein the green ceramic mother block is divided into a plurality of pieces by dicing so that the plurality of holes are removed. The cutting lines include a plurality of first cutting lines along a first direction and a plurality of second cutting lines along a second direction perpendicular to the first direction,
The manufacturing of the ceramic electronic component according to any one of claims 1 to 3, wherein at least one of the plurality of holes is formed on an intersection of the first cutting line and the second cutting line. Method.   The method for manufacturing a ceramic electronic component according to any one of claims 1 to 4, wherein the ceramic mother block is pressed after the second step and before the third step.

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