JP2005079529A - Manufacturing method of ceramic electronic component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To chamfer a ceramic element assembly without causing the occurrence of structural defects such as the peeling, delamination, cracking, chipping, etc. of the ceramic element assembly. <P>SOLUTION: A plurality of ceramic element assemblies 1 are held in such an attitude that the exposed end faces 5a and 5b of internal electrodes 3a and 3b are roughly perpendicular to a mounting surface in such a manner as to form a predetermined gap G between the ceramic element assemblies 1. Sandblasting is performed from the upper side along the gap G between the ceramic element assemblies 1 to bevel a ridgeline part 21a on one main surface side of the ceramic element assembly 1. After the ceramic element assembly 1 is reversed, sandblasting is performed from the upper side along the gap G between the reversed ceramic element assemblies 1 to chamfer the ridgeline part 21b on the other main surface side of the ceramic element assembly 1. A mother lamination is cut by a dicing method, so that a plurality of ceramic element assemblies 1 are held in such a mode that a predetermined gap G is formed between the ceramic element assemblies 1. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for manufacturing a ceramic electronic component, and more particularly to an improvement in a method for chamfering a ceramic body constituting a ceramic electronic component.

  One typical ceramic electronic component is a multilayer ceramic capacitor as shown in FIG. This multilayer ceramic capacitor has a structure in which a plurality of internal electrodes 3a, 3b are arranged to face each other with a ceramic layer 2 therebetween, and one end side thereof is alternately drawn out to different end faces 5a, 5b. A ceramic element 1 is provided, and a pair of external electrodes 4a and 4b are disposed on both ends of the ceramic element 1 so as to be electrically connected to the internal electrodes 3a and 3b.

  In general, such a multilayer ceramic capacitor is formed by laminating ceramic green sheets provided with an internal electrode pattern, and laminating ceramic green sheets for outer layers not provided with an internal electrode pattern on both upper and lower surfaces thereof, followed by pressure bonding. Then, the obtained mother laminate is cut at a predetermined position and divided into individual ceramic bodies (ceramic elements), then the ceramic bodies are fired, and both ends of the obtained sintered body (ceramic elements) It is manufactured by applying and baking a conductive paste to form an external electrode.

By the way, an individual unfired ceramic body obtained by cutting the mother laminated body at a predetermined position, or a ceramic body fired from this, is likely to be cracked or chipped at the ridge line portion or the like. Therefore, a chamfering process is performed on the ceramic body in order to prevent such cracking and chipping of the ceramic body.
And as a method of this chamfering treatment, the ceramic body is usually put into a barrel together with a polishing medium (cobble ball), and the ceramic bodies are brought into contact with each other or the ceramic body and the polishing medium are brought into contact by rotating the barrel. In general, a barrel polishing method for chamfering a ceramic body is used.

However, in fact, during barrel polishing, structural defects such as peeling, delamination, cracking and chipping occur in the ceramic body due to collisions between the ceramic bodies and between the ceramic body and the polishing medium. There is a problem.
Therefore, in order to avoid the occurrence of such a structural defect, a device has been devised to reduce the collision energy by reducing the polishing medium or lowering the rotational speed of the barrel. There is a problem that the time required for the process becomes longer and the productivity is lowered (for example, see Patent Document 1).

  On the other hand, a method of polishing an end face of a ceramic body (raw chip body) by sandblasting in an unfired stage to expose internal electrodes (for example, refer to Patent Document 2), or an end face of a fired ceramic body Is known by sandblasting to expose internal electrodes (for example, see Patent Document 3).

  However, in these methods, the ceramic body is sandblasted from the end surface side from which the internal electrode is drawn, and polishing is performed with the side surface of the ceramic body held by a holder or the like. There is a possibility that a portion that is not chamfered remains on the side surface, and that the portion is cracked or chipped.

  In addition, when sandblasting is performed perpendicularly to the end face of the ceramic body, there is a problem in that the powder particles are sprayed to the laminated interface with a relatively strong force, and there is a possibility that peeling occurs at the laminated interface.

The present invention solves the above-described problems, and can perform chamfering without causing structural defects such as peeling, delamination, cracking and chipping of the ceramic body, and is a highly reliable ceramic electronic device. It is an object of the present invention to provide a method for manufacturing a ceramic electronic component capable of efficiently manufacturing a component.
JP-A-8-069943 JP 7-235442 A Japanese Patent Laid-Open No. 5-326319

In order to achieve the above object, a method for producing a ceramic electronic component of the present invention (Claim 1) comprises
(a) A plurality of ceramic elements having a structure in which internal electrodes are exposed on the end faces, in a posture such that the exposed end faces of the internal electrodes are substantially perpendicular to the mounting surface, and between the ceramic element bodies Holding in a manner such that a predetermined gap is formed in
(b) performing sandblasting from above along the gap between the ceramic element bodies, and chamfering the one main surface side ridge line part of the ceramic element body;
(c) Inverting the ceramic body so that the exposed end face of the internal electrode is substantially perpendicular to the mounting surface, and a predetermined gap is formed between the ceramic bodies. Holding in an aspect;
(d) performing a sandblast from above along the gap between the inverted ceramic bodies and chamfering the ridge line portion on the other main surface side of the ceramic body.

The method for manufacturing a ceramic electronic component according to claim 2
While holding the ceramic body in the step (a), using a first pressure-sensitive adhesive sheet having a predetermined adhesive strength,
In the step (c), one of the ceramic bodies held by the first pressure-sensitive adhesive sheet using a second pressure-sensitive adhesive sheet having a larger adhesive strength than the first pressure-sensitive adhesive sheet used in the step (a) The second adhesive sheet is attached to the main surface, the first adhesive sheet is peeled off from the other main surface of the ceramic body, the ceramic body is transferred to the second adhesive sheet, and the ceramic body is inverted. It is characterized by

The method for manufacturing a ceramic electronic component according to claim 3 comprises:
In order to hold the ceramic body in the step (a), using the first pressure-sensitive adhesive sheet that loses the adhesive strength at a predetermined temperature,
In the step (c), a ceramic held on the first pressure-sensitive adhesive sheet using a second pressure-sensitive adhesive sheet that does not lose its adhesive strength to a temperature higher than that of the first pressure-sensitive adhesive sheet used in the step (a). After the second pressure-sensitive adhesive sheet is attached to one main surface of the element body, the first pressure-sensitive adhesive sheet loses the adhesive strength, but the second pressure-sensitive adhesive sheet is heated to a temperature at which the adhesive strength is not lost. The element body is peeled from the first pressure-sensitive adhesive sheet, the ceramic body is transferred from the first pressure-sensitive adhesive sheet to the second pressure-sensitive adhesive sheet, and the ceramic body is inverted.

  In the method of manufacturing a ceramic electronic component according to claim 4, in the step (a), the mother laminated body is cut by a dicing method so that a plurality of ceramic element bodies are exposed on the exposed end surfaces of the internal electrodes. It is characterized in that it is held in such a manner that a predetermined gap is formed between the ceramic bodies in a posture that is substantially perpendicular to the mounting surface.

  The method of manufacturing a ceramic electronic component according to the present invention (Claim 1) is to provide a plurality of ceramic bodies in a posture such that the exposed end surface of the internal electrode is substantially perpendicular to the mounting surface. The ridge line part of one main surface side of the ceramic body is chamfered by sandblasting from above along the gap between the ceramic body so as to invert the ceramic body. After that, by crushing the ridge line part on the other main surface side of the ceramic body by performing sandblasting from above along the gap between the inverted ceramic bodies, peeling or delamination of the ceramic body, It is possible to reliably chamfer the ridge line part of the ceramic body without causing structural defects such as cracks and chipping. Sinterability parts electrode is good, it is possible to manufacture a highly reliable ceramic electronic component efficiently.

  Further, as in the method of manufacturing a ceramic electronic component according to claim 2, the first adhesive sheet having a predetermined adhesive force is used to hold the ceramic body first, and the ceramic body is held after inversion. In addition, the second pressure-sensitive adhesive sheet having a larger adhesive strength than the first pressure-sensitive adhesive sheet is used, and the second pressure-sensitive adhesive sheet is attached to one main surface of the ceramic body held by the first pressure-sensitive adhesive sheet, The ceramic body is easily and reliably reversed by peeling the adhesive sheet from the other main surface of the ceramic body and transferring the ceramic body to the second adhesive sheet and inverting the ceramic body. It becomes possible to make the present invention more effective.

  In addition, as in the method of manufacturing a ceramic electronic component according to claim 3, the first pressure-sensitive adhesive sheet that loses adhesive strength at a predetermined temperature is used to hold the ceramic body first, and the step (a) Using the second adhesive sheet that does not lose its adhesive strength to a temperature higher than that of the first adhesive sheet used in the above, the second adhesive sheet is attached to one main surface of the ceramic body held by the first adhesive sheet. After pasting, the first pressure-sensitive adhesive sheet loses adhesive strength, but the second pressure-sensitive adhesive sheet is heated to a temperature at which the adhesive strength is not lost, and the ceramic body is peeled off from the first pressure-sensitive adhesive sheet, By transferring the ceramic body from the first pressure-sensitive adhesive sheet to the second pressure-sensitive adhesive sheet and inverting the ceramic body, the ceramic body can be easily and reliably reversed, and the present invention is more effective. Storm It becomes possible.

  Further, when the mother laminated body held on the adhesive sheet is cut by the dicing method, for example, as in the method for manufacturing a ceramic electronic component according to claim 4, a plurality of ceramic bodies are simply cut. The exposed end face of the internal electrode can be held in such a posture that it is substantially perpendicular to the mounting surface, and a predetermined gap is formed between the ceramic bodies. Since the ceramic body can be chamfered immediately by sandblasting in the state, sandblasting can be performed extremely efficiently, and the present invention can be further effectively realized.

  Hereinafter, examples of the present invention will be shown and the features thereof will be described in more detail.

  In the first embodiment, as shown in FIG. 8, a plurality of internal electrodes 3a, 3b are arranged so as to face each other with the ceramic layer 2 therebetween, and end faces 5a, 5b on one side which are alternately different from each other. A multilayer ceramic capacitor having a structure in which a pair of external electrodes 4a and 4b are provided on both ends of the ceramic element 1 so as to be electrically connected to the internal electrodes 3a and 3b. A case where a chamfering process is performed on the ceramic body in the process of performing will be described as an example.

(1) First, a ceramic raw material mainly composed of BaTiO ₃ is mixed with an organic solvent and an organic binder in a ball mill, and formed using a doctor blade to produce a ceramic green sheet. (Internal electrode pattern) was printed.
(2) Then, 380 layers of ceramic green sheets on which internal electrode patterns are printed are laminated, and ceramic green sheets on which no internal electrode patterns are printed (ceramic green sheets for outer layers) are laminated on the top and bottom, and then the laminated body Was pressed at a predetermined pressure to form a mother laminate.
(3) Next, as shown in FIG. 1, the mother laminate 10 was held on the first pressure-sensitive adhesive sheet 11. At this time, as the first pressure-sensitive adhesive sheet 11, the ceramic body 1 (1a) which is foamed and loses its adhesiveness by being heated to 100 ° C. (see FIG. 2 (a), (b), etc.) A pressure-sensitive adhesive sheet (100 ° C. foam release sheet) was used.
(4) Then, using a dicing saw, the mother multilayer body 10 was cut so that the final size of the multilayer ceramic capacitor was 2.0 × 1.25 × 1.25 mm, and FIG. , (B) was divided into unfired ceramic body (raw chip) 1 (1a).
(5) Thereafter, as shown in FIGS. 3 (a) and 3 (b), along the gap G between the ceramic bodies 1, from the nozzle 13 on the one main surface side (upper side), # 800 (about 10 μm grains) (Diameter) media (alumina in Example 1) was blown to perform sand blasting, and the one main surface side ridge line portion 21a of the ceramic body 1 (1a) was cut and chamfered.
(6) Next, as shown in FIG. 4, the second pressure-sensitive adhesive sheet 12 (in this Example 1, 120 ° C. foam release sheet (which is foamed by heating to 120 ° C. and loses its adhesive strength) The adhesive sheet from which the ceramic body is peeled)) is attached to one main surface (the upper surface in FIG. 4) of the ceramic body 1 (1a), then inverted, heated to 100 ° C., The first adhesive sheet 11 was peeled off, and the ceramic body 1 was held on the second adhesive sheet 12 as shown in FIG.
(7) Then, as shown in FIGS. 6 (a) and 6 (b), sandblasting is performed by spraying # 800 media (powder) from above along the gap G between the ceramic bodies 1 (1a). Then, the other main surface side ridge line portion 21b of the ceramic body 1 (1a) was cut and chamfered.
(8) Next, heat treatment was performed at 120 ° C., and the ceramic body 1 (1 a) (FIG. 7) was peeled from the second adhesive sheet 12.
(9) Thereafter, the binder was removed at 250 ° C. for 3 hours in the air, and then the ceramic body was fired at 1220 ° C.

  And the roundness (curvature radius R of the ridgeline part (corner part)) given to the ridgeline part of the obtained ceramic body (ceramic element) after firing, and structural defects such as peeling, delamination, cracking and chipping The incidence was examined. The results are shown in Table 1.

  For comparison, the ceramic body is chamfered by a barrel polishing method, and other processes are performed under the same method and conditions as in Example 1 above, and a comparative sample (comparative example). Was made. The results are also shown in Table 1.

  As shown in Table 1, in the sample of the comparative example (conventional example) chamfered by the barrel polishing method, the structural defect occurrence rate increases as the roundness (curvature radius R) of the ridge line portion to be secured increases. When the radius R is 80 μm, the structural defect rate is 0.6%, when the radius of curvature R is 100 μm, the structural defect rate is 5.4%, and when the radius of curvature R is 120 μm, the structural defect rate is 13. However, for the sample chamfered by the sandblasting method according to Example 1 of the present invention, no occurrence of structural defects was observed in any of the curvature radii R of 80 μm, 100 μm, and 120 μm. It was.

  From the results of Example 1 above, in the case of the chamfering method by the sandblasting method of the present invention, as in the case of chamfering by the barrel polishing method, it is possible to suppress and prevent the multi-faceted impact on the ceramic body. It was confirmed that chamfering can be efficiently performed without causing structural defects such as peeling, delamination, cracking and chipping. Therefore, according to the present invention, it is possible to efficiently and reliably manufacture a highly reliable ceramic electronic component.

  Further, as in the first embodiment, in the method of the present invention, since sandblasting is performed from above (from the upper surface side of the ceramic body) along the gap between the ceramic bodies, the sandblasting is performed. Although the powder particles to be sprayed polish the end surfaces, the powder particles are sprayed with a relatively weak force as compared with the case where sandblasting is performed perpendicularly to the end surfaces of the ceramic body.

  Further, in the barrel polishing method, the polishing state depends on the size and shape of the ceramic body or the relationship between the ceramic body and the size of the polishing medium, and the size of the curvature radius R obtained by barrel polishing and the structural defect occurrence rate vary. However, according to the method of the present invention as shown in the first embodiment, there is no such limitation, the conditions are fixed, and the ceramic can be efficiently processed. It becomes possible to chamfer the element body.

  In Example 1 above, a 100 ° C. foamed release sheet was used as the first pressure-sensitive adhesive sheet, and a 120 ° C. foamed release sheet was used as the second pressure-sensitive adhesive sheet. Using the pressure-sensitive adhesive sheet, using the second pressure-sensitive adhesive sheet having a larger adhesive force than the first pressure-sensitive adhesive sheet as the second pressure-sensitive adhesive sheet, on one main surface of the ceramic body held by the first pressure-sensitive adhesive sheet, The second adhesive sheet is pasted, the first adhesive sheet is peeled off from the other main surface of the ceramic body, the ceramic body is transferred to the second adhesive sheet, and the ceramic body is inverted. It is also possible to do.

(1) First, a ceramic raw material mainly composed of BaTiO ₃ is mixed with an organic solvent and an organic binder in a ball mill, and formed using a doctor blade to produce a ceramic green sheet. (Internal electrode pattern) was printed.
(2) Then, 380 layers of ceramic green sheets on which internal electrode patterns are printed are laminated, and ceramic green sheets on which no internal electrode patterns are printed (ceramic green sheets for outer layers) are laminated on the top and bottom, and then the laminated body Was pressed at a predetermined pressure to form a mother laminate.
(3) Then, using a dicing saw, the mother multilayer body 10 is cut so that the final multilayer ceramic capacitor size is 2.0 × 1.25 × 1.25 mm, and the unfired ceramic element is cut. The body (raw chip) 1 (1a) was divided.
(4) Thereafter, the binder was removed at 250 ° C. for 3 hours in the air, and then the ceramic body was fired at 1220 ° C.
(5) The obtained fired ceramic bodies (ceramic elements) were aligned by a transfer jig so as to ensure a predetermined interval.
(6) Then, a 100 ° C. foam release sheet is attached as the first pressure-sensitive adhesive sheet 11 from the top of the ceramic body 1 and inverted, and as shown in FIGS. 3 (a) and 3 (b), The first main surface of the ceramic body 1 is sandblasted by spraying # 800 media (powder) from the nozzle 13 on the first main surface side (upper side) along the gap G between the first ceramic body 1. The side ridge line portion 21a was cut and chamfered.
(7) Then, as shown in FIG. 4, as the second adhesive sheet 12, a 120 ° C. foam release sheet is attached to one main surface (upper surface in FIG. 4) of the ceramic body 1, and then inverted. The first pressure-sensitive adhesive sheet 11 was peeled off by heating to 100 ° C., and the ceramic body 1 was held on the second pressure-sensitive adhesive sheet 12 as shown in FIG.
(8) Then, as shown in FIGS. 6 (a) and 6 (b), sandblasting is performed by spraying # 800 media (powder) from above along the gap G between the ceramic bodies 1, The other principal surface side ridge line portion 21b of the ceramic body 1 was cut and chamfered.
(9) Next, heat treatment was performed at 120 ° C., and the ceramic body 1 (FIG. 7) was peeled from the second adhesive sheet 12.

  As a result of examining the roundness (curvature radius of curvature R of the corner part) given to the ridge line part of the obtained ceramic body (ceramic element) after firing and the occurrence rate of structural defects such as delamination, chipping and cracking, Similar to the case of Example 1 in which the ceramic body was chamfered at the stage of firing, in the case of Example 2 in which chamfering was performed by the sandblasting method after firing, the size of the radius of curvature R (80 μm, 100 μm, Regardless of 120 μm), no structural defects were observed.

  From this Example 2, it was confirmed that the present invention is applicable not only to chamfering an unfired ceramic body but also to chamfering a fired ceramic body.

  According to the present invention, it is possible to efficiently chamfer without causing structural defects such as peeling, delamination, cracking and chipping, and to efficiently manufacture a highly reliable ceramic electronic component. It becomes possible. Therefore, the present invention can be widely applied to the technical field of manufacturing various ceramic electronic components including a multilayer ceramic capacitor that require a chamfering process.

It is a figure which shows the state which hold | maintained the ceramic green sheet to the 1st adhesive sheet in 1 process of the manufacturing method of the ceramic electronic component concerning one Example of this invention. (a) is a step of manufacturing a ceramic electronic component according to an embodiment of the present invention, wherein the ceramic green sheet held on the first adhesive sheet is cut by a dicing saw and divided into individual ceramic bodies. The front view which shows a state, (b) is a top view. (a) is the state which is chamfering the one main surface side ridgeline part of the ceramic body hold | maintained at the 1st adhesive sheet in 1 process of the manufacturing method of the ceramic electronic component concerning one Example of this invention. (B) is a diagram schematically showing an enlarged main part thereof. It is a figure which shows the state which affixed the 2nd adhesive sheet on the one main surface of the ceramic element body in 1 process of the manufacturing method of the ceramic electronic component concerning one Example of this invention. It is a figure which shows the state which reversed the ceramic body in one process of the manufacturing method of the ceramic electronic component concerning one Example of this invention. (a) is the state which is chamfering the other main surface side ridgeline part of the ceramic body hold | maintained at the 2nd adhesive sheet in 1 process of the manufacturing method of the ceramic electronic component concerning one Example of this invention. (B) is a diagram schematically showing an enlarged main part thereof. It is a figure which shows the ceramic element | base_body which chamfered with the manufacturing method of the ceramic electronic component concerning one Example of this invention. It is a figure which shows the ceramic electronic component (multilayer ceramic capacitor) manufactured by the manufacturing method of the ceramic electronic component concerning one Example of this invention.

Explanation of symbols

1 Ceramic element (ceramic body)
DESCRIPTION OF SYMBOLS 1a Unbaked ceramic body 2 Ceramic layer 3a, 3b Internal electrode 4a, 4b External electrode 5a, 5b End face of ceramic element 10 Mother laminated body 11 First adhesive sheet 12 Second adhesive sheet 13 Nozzle 21a One main surface side Edge line part 21b The other main surface side edge line part G Gap

Claims (4)

(a) A plurality of ceramic elements having a structure in which internal electrodes are exposed on the end faces, in a posture such that the exposed end faces of the internal electrodes are substantially perpendicular to the mounting surface, and between the ceramic element bodies Holding in a manner such that a predetermined gap is formed in
(b) performing sandblasting from above along the gap between the ceramic element bodies, and chamfering the one main surface side ridge line part of the ceramic element body;
(c) Inverting the ceramic body so that the exposed end face of the internal electrode is substantially perpendicular to the mounting surface, and a predetermined gap is formed between the ceramic bodies. Holding in an aspect;
(d) a step of sandblasting from above along the gap between the inverted ceramic element bodies, and chamfering the ridge line part on the other main surface side of the ceramic element body. Method. While holding the ceramic body in the step (a), using a first pressure-sensitive adhesive sheet having a predetermined adhesive strength,
In the step (c), one of the ceramic bodies held by the first pressure-sensitive adhesive sheet using a second pressure-sensitive adhesive sheet having a larger adhesive strength than the first pressure-sensitive adhesive sheet used in the step (a) The second adhesive sheet is attached to the main surface, the first adhesive sheet is peeled off from the other main surface of the ceramic body, the ceramic body is transferred to the second adhesive sheet, and the ceramic body is inverted. The method of manufacturing a ceramic electronic component according to claim 1, wherein: In order to hold the ceramic body in the step (a), using the first pressure-sensitive adhesive sheet that loses the adhesive strength at a predetermined temperature,
In the step (c), a ceramic held on the first pressure-sensitive adhesive sheet using a second pressure-sensitive adhesive sheet that does not lose its adhesive strength to a temperature higher than that of the first pressure-sensitive adhesive sheet used in the step (a). After the second pressure-sensitive adhesive sheet is attached to one main surface of the element body, the first pressure-sensitive adhesive sheet loses the adhesive strength, but the second pressure-sensitive adhesive sheet is heated to a temperature at which the adhesive strength is not lost. The element body is peeled off from the first adhesive sheet, the ceramic element body is transferred from the first adhesive sheet to the second adhesive sheet, and the ceramic element body is inverted. The manufacturing method of the ceramic electronic component of description.   In the step (a), the mother laminated body is cut by a dicing method, so that the plurality of ceramic bodies are arranged in such a posture that the exposed end surfaces of the internal electrodes are substantially perpendicular to the mounting surface. The method for producing a ceramic electronic component according to claim 1, wherein the ceramic electronic component is held in such a manner that a predetermined gap is formed between the ceramic bodies.

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