JP2007266282A - Multilayer ceramic electronic component and method of manufacturing same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method capable of forming a highly dense wiring with sufficiently high accuracy while suppressing connection failure etc., and sufficiently suppressing the occurrence of cracks in the inside of a multilayer ceramic electronic component. <P>SOLUTION: The method of manufacturing the multilayer ceramic component is provided with a step of forming a laminate sheet 41 in which ceramic green sheets 20A, 20B and a conductor paste layer 30A are alternately laminated, on a carrier film 6 so that at least the uppermost layer on a side opposite to the carrier film 6 may become the ceramic green sheet 20B; a step of forming laminate units 15 each having the laminate sheet 41 and a conductor paste portion 50 for a via on the carrier film 6; a step of laminating the plurality of laminate units 15; and a step of baking the plurality of laminate units 15 laminated to form a laminate, in which ceramic layer and an internal electrode layer are alternately laminated and a via electrode. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a multilayer ceramic electronic component and a method for manufacturing the same.

  As a multilayer ceramic electronic component in which a plurality of ceramic layers and internal electrode layers are alternately stacked, a multilayer ceramic wiring board, a multilayer ceramic capacitor, a multilayer piezoelectric element, a multilayer ceramic package, and the like are known. In these multilayer ceramic electronic components, in order to reduce the equivalent series resistance and the equivalent series inductance, a structure in which internal electrode layers are connected by a via-hole conductor (via electrode) inside the multilayer structure is often employed.

  In general, a multilayer ceramic electronic component is manufactured by a method of preparing a plurality of sheet-like materials of a part constituting a part of the multilayer structure and firing a multilayer structure obtained by further laminating them. The sheet-like material includes, for example, ceramic green sheets and conductor paste layers that are alternately stacked, and via conductor paste filled in through holes that penetrate the sheet.

  Such a sheet-like material (laminated body unit) includes, for example, a process in which a ceramic green sheet is formed and a conductor paste for forming an internal electrode layer is printed in a predetermined pattern on the ceramic green sheet. A step of forming a paste layer, a step of forming a through hole at a predetermined position using a laser, punching, micro drill, etc., and filling the through hole with a conductive paste for forming a via electrode (via conductive paste) And a step of forming a via conductor paste portion. When filling via holes with via conductor paste, via conductors are used to ensure filling of the through holes and ensure the connection of via electrodes even when there is some misalignment during printing or lamination. The paste is printed in a pattern slightly larger than the diameter of the through hole. Therefore, in the via conductor paste portion, a protruding portion is formed in which the via conductor paste protruding from the through hole protrudes on the ceramic green sheet or the internal electrode layer in the vicinity of the opening of the through hole. In order to prevent poor connection, it is advantageous that the size of the overhanging portion is large. However, if the overhanging portion size is increased, the via electrode should be in contact with the internal electrode layer that should not be in contact with the increase in wiring density. As a result, short circuits are likely to occur, which is disadvantageous in terms of downsizing electronic components.

  More specifically, a multilayer unit used for manufacturing a multilayer ceramic electronic component is more specifically formed, for example, by forming a through hole to be a via hole at a predetermined position of a ceramic green sheet formed on a carrier film, and the through hole After the via conductor paste is filled in by screen printing, the conductive paste layer for the internal electrode layer is formed by screen printing. However, in this method, the conductor paste for forming the conductor pattern layer is printed on the surface where the flatness is greatly reduced because the protruding portion of the conductor paste for vias is raised. Thus, it was difficult to form a high-density conductor pattern layer by printing a conductor paste.

  With respect to this problem, for example, a method as shown in FIG. 1 has been proposed (Patent Document 1). In this method, the ceramic green sheet 20 is formed on the carrier film 6 (a), the conductor paste layer 30 is first formed thereon (b), and then the through hole 10 is formed (c). The via conductor paste 50 is formed by filling the via conductor paste therewith. The via conductor paste portion 50 has a protruding portion 50 a that protrudes toward the ceramic green sheet 20 or the conductive paste layer 30 in the vicinity of the opening of the through hole 10.

  A multilayer ceramic electronic component as shown in the schematic cross-sectional view of FIG. 2 is obtained by laminating and firing a plurality of laminate units 15 obtained by the method shown in FIG. The via electrode 5 of the multilayer ceramic electronic component 1 shown in FIG. 2 has a protruding portion 5a derived from the protruding portion 50a. The overhanging portion 5a is in contact with the internal electrode layer 3A or 3B or is formed in the same plane without being in contact therewith.

On the other hand, as a method of increasing the size of the via conductor paste overhang while ensuring high-density wiring, a through hole is formed so that the carrier film is penetrated together with the ceramic green sheet, and air is passed from the ceramic green sheet side. A method has been proposed in which via conductor paste is supplied to the carrier film side while sucking through a conductive sheet to fill the through hole with the via conductor paste (Patent Document 2). In this method, the overhanging portion of the via conductor paste is formed on the back side of the carrier film, and is removed along with the peeling of the carrier film. Thereby, the problem of the occurrence of a short circuit due to the contact between the internal electrode layer and the via electrode in the high-density wiring can be solved.
JP-A-5-191048 JP-A-5-167254

  However, in the case of the method described in Patent Document 1, for example, if the overhanging portion is enlarged in order to prevent connection failure, a problem of short circuit occurs, so that it is difficult to form high-density wiring. Further, when a multilayer ceramic electronic component having a particularly high density wiring is manufactured, many cracks are generated in the resulting multilayer ceramic electronic component due to the thermal history received during manufacture and use. As a result of examination by the present inventors, it has become clear.

  On the other hand, in the case of the method described in Patent Document 2, since pressure is applied to the ceramic green sheet in a state where the breathable sheet is in contact with the ceramic green sheet, the ceramic green sheet is easily damaged. This is considered not to be a big problem when the ceramic green sheet is thick enough, but in electronic parts with a thinner film, fatal defects such as the occurrence of a short circuit due to damage to the ceramic layer are not possible. There was a case to cause.

  The present invention has been made in view of the above circumstances, and is capable of forming a high-density wiring with sufficiently high accuracy while preventing poor connection and damage to the ceramic layer, and the obtained multilayer ceramic. An object of the present invention is to provide a method for manufacturing a multilayer ceramic electronic component capable of sufficiently suppressing the occurrence of cracks inside the electronic component.

  The present invention provides a multilayer ceramic comprising a laminate in which ceramic layers and internal electrode layers are alternately laminated, and via electrodes formed so as to connect a plurality of different internal electrode layers inside the laminate. A method of manufacturing an electronic component, wherein a laminated sheet in which ceramic green sheets and patterned conductor paste layers are alternately laminated on a carrier film is formed so that at least the outermost layer on the opposite side of the carrier film becomes a ceramic green sheet Forming a laminated sheet forming step, forming a through hole penetrating the laminated sheet, forming a via conductor paste portion filling the through hole, and forming a laminate unit having the laminated sheet and via conductor paste portion A laminate unit forming step formed on a carrier film and a plurality of laminate units having the same or different laminate configuration A stacking step of stacking the stacks so that the respective through holes overlap each other, and a firing step of firing the stacked structure including a plurality of stacked stack units to form the stacked body and the via electrode. .

  According to this manufacturing method, the conductive paste layer as the precursor of the internal electrode layer is formed on the surface having high flatness before the formation of the through hole and the filling of the via conductor paste. It is possible to form the internal electrode layer with sufficiently high accuracy.

  Further, according to this manufacturing method, since the via conductor paste is filled from the surface of the ceramic sheet located at the outermost layer, the overhanging portion of the via conductor paste is formed on a different surface from the conductor paste layer. . Thereby, even if the dimension of the projecting portion of the via conductor paste portion is increased, occurrence of a short circuit due to contact between the via electrode and the internal electrode layer is sufficiently prevented. In other words, it has become possible to sufficiently increase the wiring density of electronic components while preventing poor connections and short circuits.

  In addition, since the overhanging portion of the via conductor paste portion is formed on a surface different from the conductor paste layer, it is possible to sufficiently prevent the occurrence of cracks in the obtained multilayer ceramic electronic component. It was. Such effects are obtained by the fact that the thermal stress generated in the laminate due to the difference in thermal shrinkage and expansion coefficient of each constituent material is distributed in a wider range in the laminate. it is conceivable that.

  Further, since the breathable sheet is not pressed against the ceramic green sheet as in the method described in Patent Document 2, damage to the ceramic layer is prevented.

  Preferably, in the laminated sheet forming step, the laminated sheet is formed such that the outermost layers on both sides thereof become ceramic green sheets, and in the laminating step, the ceramic green sheet formed on the outermost layer on the opposite side of the carrier film, and the carrier A plurality of laminate units are laminated so that the through-holes overlap each other in the direction in which the ceramic green sheet formed on the outermost layer on the side adjacent to the film is adjacent.

  Thereby, it becomes particularly easy to peel the carrier film from the laminate unit, and the production efficiency is improved. When the layer adjacent to the carrier film is a conductor paste layer, a part of the conductor paste layer may remain on the carrier film when the carrier film is peeled off, but the layer adjacent to the carrier film should be a ceramic green sheet. Such a problem is sufficiently prevented.

  Preferably, in the laminated sheet forming step, the ceramic green sheet located in the outermost layer is fired after firing another ceramic green sheet laminated so that the thickness after firing is adjacent to the ceramic green sheet in the laminating step And a thickness corresponding to the interval between adjacent internal electrode layers.

  The multilayer ceramic electronic component of the present invention includes a laminate in which ceramic layers and internal electrode layers are alternately laminated, and via electrodes formed so as to connect a plurality of different internal electrode layers within the laminate. The via electrode has a protruding portion that protrudes in a direction parallel to the main surface of the internal electrode layer without contacting the internal electrode layer at a portion where the position in the stacking direction of the multilayer body is different from the internal electrode layer. It is what you are doing.

  The multilayer ceramic electronic component of the present invention can be suitably manufactured by the manufacturing method of the present invention. In this multilayer ceramic electronic component, the overhang portion derived from the overhang portion of the via conductor paste is formed on a different surface from the internal electrode layer. Thereby, the thermal stress is dispersed in a wide range, and the occurrence of cracks due to the thermal history or the like is sufficiently prevented.

  According to the method for manufacturing a multilayer ceramic electronic component of the present invention, it is possible to form a high-density wiring with sufficiently high accuracy while preventing connection failure and damage to the ceramic layer, and the multilayer ceramic electronic to be obtained is obtained. It is possible to sufficiently suppress the occurrence of cracks inside the component.

  Also, in the manufacturing method of the present invention, since the via conductor paste is filled on the carrier film, a multilayer unit for obtaining a multilayer ceramic electronic component by adopting a continuous process by a reel method is extremely high. It can be obtained with production efficiency.

  Hereinafter, preferred embodiments of the present invention will be described in detail. However, the present invention is not limited to the following embodiments. In addition, the same code | symbol is attached | subjected to the element which is the same or it corresponds through all the figures. In addition, overlapping descriptions are omitted as appropriate.

  FIG. 3 is a schematic cross-sectional view showing an embodiment of the multilayer ceramic electronic component according to the present invention. A multilayer ceramic electronic component 1 shown in FIG. 3 is an electronic component that functions as a capacitor (ie, a multilayer ceramic capacitor). In this multilayer ceramic electronic component 1, a multilayer body 4 in which ceramic layers 2 and internal electrode layers 3A and 3B are alternately laminated, and the internal electrode layers 3A or the internal electrode layers 3B are connected to each other inside the multilayer body 4. And the upper cover layer 21 provided on one side of the laminate 4 and the lower cover layer 22 provided on the opposite side. Further, the via electrode 5 is drawn out through a through hole formed in the upper cover layer 21, and a terminal electrode 7 is provided so as to be in contact with the drawn via electrode 5. The terminal electrode 7 is used for connection with a bump electrode on a mounting substrate on which the multilayer ceramic electronic component 1 is mounted.

The ceramic layer 2 is made of a ceramic material having a dielectric constant high enough to be applied as a material for a dielectric layer in a ceramic capacitor. Specifically, for example, barium titanate (BaTiO ₃ ) -based materials, lead composite perovskite compound-based materials, and strontium titanate-based (SrTiO ₃ ) materials are suitable. The upper cover layer 21 and the lower cover layer 22 are also made of the same ceramic material.

  The thickness T of the ceramic layer 2 between the adjacent internal electrode layers 3A and 3B (that is, the interval between the internal electrode layers, hereinafter referred to as “interlayer thickness” in some cases) is preferably 1 to 25 μm. In addition, in the part which the adjacent ceramic layers 2 contact | connect, and the part which contact | connects the ceramic layer 2 and the upper cover layer 21 or the lower cover layer 22, it is integrated so that the boundary cannot be visually recognized normally.

  In the laminate 4, the internal electrode layers 3 </ b> A and 3 </ b> B having different patterns are alternately laminated with the ceramic layer 2 interposed therebetween. The internal electrode layer 3A and the internal electrode layer 3B have a pattern in which a plurality of circular openings 33A and 33B are formed so that their positions do not overlap each other. A function as a capacitor is manifested in portions other than the openings 33A and 33B of the adjacent internal electrode layers 3A and 3B.

  The via electrode 5 is positioned in a direction parallel to the main surface of the internal electrode layers 3A and 3B without contacting the internal electrode layers 3A and 3B at a portion where the position of the stacked body 4 in the stacking direction is different from the internal electrode layers 3A and 3B. An overhanging portion 5a is provided. The overhang portion 5 a is a portion formed from the overhang portion 50 a of the via conductor paste portion 50 in the multilayer unit 15.

  The internal electrode layers 3A and 3B, the via electrode 5 and the terminal electrode 7 are made of a conductive material having a conductivity that can function as an electrode. Examples of the conductive material include Ni, Ag, Cu, Pt, Pd, and alloys containing these as main components.

  The multilayer ceramic electronic component 1 can be manufactured, for example, by the manufacturing method shown in FIG. FIG. 4 is a flowchart showing an embodiment of the manufacturing method according to the present invention. In this embodiment, a laminated sheet forming step S1 for forming a laminated sheet in which ceramic green sheets and patterned conductive paste layers are alternately laminated on a carrier film, and a laminated sheet having a laminated sheet and a conductor paste portion for vias. Laminate unit forming step S2 for obtaining a body unit, laminating step S3 for laminating a plurality of laminate units having the same or different laminate configurations, and a laminated structure including a plurality of laminated unit units are fired. 4 and via electrode 5 are formed.

  FIG. 5 is a schematic cross-sectional view showing an embodiment of the laminated sheet forming step S1 and the laminated body unit forming step S2. In this embodiment, first, a ceramic green sheet 20A is formed on one surface of the carrier film 6 ((a) of FIG. 5). The ceramic green sheet 20A, which is the outermost layer on the side adjacent to the carrier film 6 of the laminated sheet 41, is laminated so that the thickness after firing is adjacent to the ceramic green sheet 20A in order to obtain the laminated ceramic electronic component 1. Together with the thickness of other ceramic green sheets after firing, the thickness is set to a thickness corresponding to the interval between adjacent internal electrode layers (interlayer thickness T of multilayer ceramic electronic component 1). Specifically, the ceramic green sheet 20A is formed to have a thickness of about ½ of the interlayer thickness T after firing, for example.

  As the carrier film 6, a film having releasability capable of peeling the formed laminate unit 15 is preferably used. Therefore, the carrier film 6 may be a resin film and a film having a release layer formed on one surface thereof, or may be a film having a release treatment applied to the surface. Specifically, the carrier film 6 is preferably a polyethylene terephthalate film or the like on which a release layer is formed or a release treatment is performed.

  The ceramic green sheet 20A is formed by applying a paste containing a ceramic raw material (hereinafter referred to as “ceramic layer paste”) that generates a ceramic material by firing on the carrier film 6 and drying it if necessary. The ceramic layer paste can be applied by a known method such as a doctor blade method.

  The ceramic layer paste is selected from, for example, various composite oxides mentioned above as ceramic materials or carbonates, nitrates, hydroxides or organometallic compounds of each metal contained therein, and combinations thereof. A paste containing a ceramic raw material is preferably used.

  The ceramic layer paste is prepared by kneading a ceramic raw material mixed with an organic vehicle or the like. An organic vehicle is a component containing a binder and a solvent. Examples of the binder for the ceramic layer paste include ethyl cellulose, polyvinyl butyral, and acrylic resin. Examples of the solvent include organic solvents such as terpineol, butyl carbitol, acetone, toluene, xylene, and ethanol.

  In addition to the above, the ceramic layer paste may contain various dispersants, plasticizers, dielectrics, glass frit and the like as necessary.

  After the formation of the ceramic green sheet 20A, the conductor paste layer 30A is formed in a predetermined pattern corresponding to the internal electrode layer 3A in the multilayer ceramic electronic component 1 ((b) of FIG. 4). The conductive paste layer 30A is formed by printing a conductive paste for forming an internal electrode layer (hereinafter referred to as “internal electrode paste”) by a known method such as screen printing, and drying it as necessary. Can do.

  The internal electrode paste contains conductive particles and an organic vehicle. The internal electrode paste is prepared by kneading conductive particles with an organic vehicle or the like. Metal particles are preferred as the conductive particles. Suitable metal particles include particles of Ni, Ag, Cu, Pt, Pd, and alloys containing these as main components. The organic vehicle in the internal electrode paste also contains a binder and a solvent. Examples of the binder include ethyl cellulose, acrylic resin, polyvinyl butyral, polyvinyl acetal, polyvinyl alcohol, polyolefin, polyurethane, polystyrene, and copolymers thereof. Examples of the solvent include terpineol, dihydroterpineol, butyl carbitol, kerosene and the like.

  The internal electrode paste may contain a plasticizer. As the plasticizer, phthalic acid esters such as benzylbutyl phthalate (BBP), adipic acid, phosphoric acid esters, glycols, and the like can be used.

  On the conductive paste layer 30A, the ceramic green sheet 20B is formed as the outermost layer on the opposite side of the carrier film 6 ((c) of FIG. 5). The ceramic green sheet 20B is preferably formed by the same method using the same material as the ceramic green sheet 20A. The thickness of the ceramic green sheet 20B is preferably combined with the thickness after firing of other ceramic green sheets laminated so that the thickness after firing is adjacent to the ceramic green sheet 20B in order to obtain the multilayer ceramic electronic component 1. And a thickness corresponding to the interval between adjacent internal electrode layers (interlayer thickness T of the multilayer ceramic electronic component 1). In the case of the present embodiment, since the ceramic green sheet 20A and the ceramic green sheet 20B are laminated so as to be adjacent to each other in the lamination step, the thickness of the ceramic green sheet 20A becomes, for example, a half of the interlayer thickness T after firing. When formed in such a manner, the thickness of the ceramic green sheet 20B is similarly formed to be a half of the interlayer thickness T after firing.

  Subsequently, the through-hole 10 which penetrates the lamination sheet 41 on the carrier film 6 in the position where the via electrode 5 should be formed is formed ((d) of FIG. 5). The through hole 10 can be formed by an ordinary method such as a mold, punching, or laser.

  Then, the via conductor paste is filled into the formed through hole 10 from the ceramic green sheet 20B side to form a via conductor paste portion ((e) of FIG. 5). The via conductor paste can be filled into the through-hole 10 by an ordinary method such as screen printing. At this time, the via conductor paste is printed in a pattern larger than the opening diameter of the through hole in order to reliably fill the through hole 10. Therefore, the via conductor paste portion 50 has a protruding portion 50 a that protrudes in the vicinity of the opening of the through hole 10 and is formed integrally with a portion in the through hole 10. As the via conductor paste, a paste similar to the internal electrode conductor paste may be used, or a paste having a different ratio between the conductive particles and the organic vehicle and the type of the conductive particles may be used.

  The multilayer unit 15 may be at least the outermost layer on the opposite side of the carrier film 6 as long as it is a ceramic green sheet. Other configurations are not particularly limited as long as they can be a part of a multilayer ceramic electronic component. Not. For example, the laminate unit 15 may have a plurality of conductor paste layers, or the conductor paste layers may be directly formed on the carrier film 6.

  FIG. 6 is a diagram showing an embodiment of a laminated sheet forming step S1 and a laminated unit forming step S2 when obtaining a laminated unit having a plurality of conductor paste layers. In the embodiment shown in FIG. 6, the ceramic green sheet 20 </ b> C is formed on the conductor paste layer 30 </ b> A formed through the same processes as in FIGS. 5A and 5B (FIG. 6C). The ceramic green sheet 20C can be formed by the same method using the same material as the ceramic green sheet 20A. However, the thickness is adjusted so as to be a thickness corresponding to the interlayer thickness T of the multilayer ceramic electronic component 1 alone after firing.

  Subsequently, formation of the conductive paste layer 30B (FIG. 6D), formation of the ceramic green sheet 20B (FIG. 6E), formation of the through-hole 10 (FIG. 6F), and via use Through the formation of the conductor paste part 50 ((g) in FIG. 6), the laminate unit 15 having the conductor paste layers 30A and 30B is obtained.

  Before the outermost ceramic green sheet 20B is formed on the conductive paste layer 30B, the ceramic green sheet and the conductive paste layer may be alternately formed a plurality of times, such as the ceramic green sheet 20C and the conductive paste layer 30A. Good. From the viewpoint of manufacturing a multilayer ceramic electronic component with high production efficiency, the multilayer unit preferably has two or more conductor paste layers. The upper limit of the number of conductor paste layers is not particularly limited, but from the viewpoint of handleability when employing a reel-type continuous process as described below, the number of conductor paste layers in the laminate unit is 10 or less. It is preferable.

  As described above, the steps until the laminate unit 15 is obtained are performed on the carrier film 6. Therefore, the laminate unit 15 can be formed by a reel-type continuous process in which unwinding and winding from the reel are repeated. For example, in the case of the above-described method of Patent Document 2, an overhang portion of the via conductor paste is formed on the back surface side of the carrier film, and when the roll is wound in this state, the overhang portion on the back surface side of the carrier film is laminated on the front surface side. Since it comes in contact with the body unit, it is extremely difficult to manufacture a laminate unit by such a continuous process. The manufacturing method according to the present embodiment is also advantageous in this respect.

  A multilayer ceramic electronic component is manufactured by combining a plurality of multilayer units and other components as necessary. FIG. 7 is a schematic cross-sectional view showing an embodiment of the stacking step S3. In the embodiment of FIG. 7, a plurality of laminated body units 15 are laminated so as to be aligned such that the ceramic green sheets 20 </ b> A and 20 </ b> B as the outermost layers are adjacent to each other and the through holes 10 overlap each other. Further, an upper cover layer green sheet 21A and a lower cover layer green sheet 22A are laminated on the upper and lower parts of the laminated structure composed of the laminate units 15, respectively, and the whole is pressed in this state. In the laminating step, instead of laminating a plurality of laminate units having the same laminating structure as in the present embodiment, a plurality of laminating structures such as the number of laminations, the thickness of each layer, and the pattern of the conductive paste layer are different from each other. You may laminate | stack combining a seed | species laminated body unit.

  The upper cover layer green sheet 21 </ b> A is a sheet having a ceramic green sheet and a via conductor paste portion formed at a position corresponding to the via conductor paste portion of the multilayer unit 15. The lower cover layer green sheet 22A is a sheet made of only a ceramic green sheet. The pressurization is performed by a method such as pressing with a die, isostatic pressing or the like. The upper cover layer green sheet 21A and the lower cover layer 22A can be used by laminating one or two or more.

  After the pressurization, the laminate 4 and the via electrode 5 are formed from the laminate structure in which the plurality of laminate units 15, the upper cover layer green sheet 21A, and the lower cover layer green sheet 21B are integrated (firing step). S4). More specifically, the ceramic layer 2, the internal electrode layer 3, and the via electrode 5 are formed by removing the binder contained in the conductor paste layers 30A and 30B and the via conductor paste portion 50 (debinding) and then firing. Is done. A chip having a predetermined size and shape may be cut out from the laminated structure before or after firing.

Debinding can be performed by heating to about 200 to 600 ° C. in air or in a reducing atmosphere such as a mixed gas of N ₂ and H ₂ . Moreover, baking can be performed by heating to 1100-1300 degreeC, preferably in a reducing atmosphere. Furthermore, after baking, the annealing treatment which hold | maintains baking products at 800-1000 degreeC for 2 to 10 hours in weakly oxidative atmosphere is given as needed.

  Finally, the terminal electrode 7 is formed and further baked to obtain the multilayer ceramic electronic component 1.

  The multilayer ceramic electronic component of the present invention is not limited to the multilayer ceramic capacitor described above. Examples of electronic components other than the multilayer ceramic capacitor include a multilayer piezoelectric element and a multilayer ceramic package. These can be manufactured in the same manner as in the above-described embodiment by appropriately changing the materials used, the laminated structure, and the like.

  Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples.

(Example)
(Production of multilayer ceramic capacitor)
First, a ceramic layer paste was applied on a polyethylene terephthalate as a carrier film by a doctor blade method and then dried to form a ceramic green sheet having a thickness of 5 μm. As ceramic layer paste, ceramic raw material mixed with multiple kinds of metal compounds to produce barium titanate ceramic material by firing, organic vehicle containing polyvinyl butyral and ethanol, and dioctyl phthalate as plasticizer A paste prepared by kneading was used.

  Next, the conductor paste for internal electrodes was printed on the ceramic green sheet by a screen printing method in a pattern having a plurality of circular openings with a diameter of 200 μm to form a conductor paste layer. As the internal electrode conductor paste, a paste prepared by kneading Ni particles (average particle size 0.4 μm) and barium titanate particles (average particle size 0.1 μm) with an organic vehicle containing ethyl cellulose and terpineol was used.

  Subsequently, the same ceramic layer paste as described above was applied onto the conductor paste layer by the doctor blade method and then dried to form a ceramic green sheet having a thickness of 5 μm. A laminated sheet on which a paste layer was formed was obtained.

  A plurality of through holes (diameter: 70 μm) were formed at predetermined intervals of the obtained laminated sheet by processing using a YAG laser at intervals of 400 μm. Then, the via conductor paste was filled into the through holes by screen printing with a circular pattern having a diameter of 150 μm to form a via conductor paste layer to obtain a multilayer unit. As the via conductor paste, a paste prepared by kneading Ni particles (average particle size 0.6 μm) and barium titanate particles (average particle size 0.1 μm) with an organic vehicle containing ethyl cellulose and terpineol was used.

  Laminate 5 ceramic green sheets (thickness 20 μm) for the lower cover layer separately prepared, and then laminate 100 laminated units peeled from the polyethylene terephthalate film while aligning the positions of the through holes. 5 sheets of green sheets (thickness 20 μm) for the upper cover layer were laminated, and the whole was pressed and integrated by pressing with a mold. As the green sheet for the upper cover layer, a ceramic green sheet was used in which a through hole was formed at a position corresponding to the through hole of the multilayer unit, and a via conductor paste layer was formed there.

  After pressing, a plurality of green chips of a predetermined size were cut out and fired by heating them at 1250 ° C. for 2 hours. The sintered body after firing was annealed by heating at 1000 ° C. for 4 hours, and then a terminal electrode was formed to obtain a multilayer ceramic capacitor.

(Evaluation of crack occurrence)
The multilayer ceramic capacitor obtained above was immersed in a solder bath at 340 ° C. for 20 seconds, and then pulled up and embedded in a thermosetting resin. Then, polishing was performed in this state to expose a cross section including the via electrode, and the cross section was observed with a microscope to confirm whether or not a crack was generated near the via electrode. Similar observations were made on 90 multilayer ceramic capacitors, and no cracks were observed in any of them. That is, the crack occurrence rate was 0%.

(Comparative example)
A ceramic green sheet having a thickness of 10 μm is formed on a polyethylene terephthalate film, and a conductive paste layer similar to that of the example is formed thereon to obtain a laminate sheet in which the outermost layer opposite to the carrier film is a conductive paste layer. It was. Then, through-holes and via conductor paste layers were formed on this laminate sheet in the same manner as in the example, to obtain a laminate unit having the same laminate structure as in FIG.

  A multilayer ceramic capacitor was produced in the same manner as in the example except that this multilayer unit was used. Then, when the crack generation state was evaluated in the same manner as in the above example, the occurrence of cracks was observed in many samples. The occurrence rate of cracks was 8.30%.

It is a schematic sectional drawing which shows a part of process of the conventional manufacturing method. It is a schematic sectional drawing which shows the conventional multilayer ceramic electronic component. 1 is a schematic cross-sectional view showing an embodiment of a multilayer ceramic electronic component according to the present invention. It is a flowchart which shows one Embodiment of the manufacturing method of the multilayer ceramic electronic component which concerns on this invention. It is a schematic sectional drawing which shows one Embodiment of laminated sheet formation process S1 and laminated body unit formation process S2. It is a schematic sectional drawing which shows one Embodiment of laminated sheet formation process S1 and laminated body unit formation process S2. It is a schematic sectional drawing which shows one Embodiment of lamination process S3.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Multilayer ceramic electronic component, 2 ... Ceramic layer, 3A, 3B ... Internal electrode layer, 4 ... Laminated body, 5 ... Via electrode, 5a ... Overhang | projection part, 15 ... Laminated body unit, 21 ... Upper cover layer, 22 ... Lower part Cover layer, 6 ... carrier film, 7 ... terminal electrode, 10 ... through hole, 20, 20A, 20B, 20C ... ceramic green sheet, 30, 30A, 30B ... conductive paste layer, 40 ... laminated sheet, 50 ... via conductor Paste part, 50a ... overhang part.

Claims (4)

A multilayer ceramic electronic component comprising: a laminate in which ceramic layers and internal electrode layers are alternately laminated; and via electrodes formed so as to connect a plurality of different internal electrode layers inside the laminate. A manufacturing method comprising:
A laminated sheet forming step of forming a laminated sheet in which ceramic green sheets and patterned conductor paste layers are alternately laminated on a carrier film so that at least the outermost layer on the opposite side of the carrier film is a ceramic green sheet;
A through hole penetrating the laminated sheet is formed, a via conductor paste portion filling the through hole is formed, and a laminate unit having the laminated sheet and the via conductor paste portion is formed on the carrier film. A laminate unit forming step,
A laminating step of laminating a plurality of the laminate units having the same or different laminate configurations so that the respective through holes overlap;
A firing process comprising firing a laminated structure including a plurality of the laminated units laminated to form the laminated body and the via electrode. In the laminated sheet forming step, the laminated sheet is formed so that outermost layers on both sides thereof are ceramic green sheets,
In the laminating step, each through hole is formed in a direction in which the ceramic green sheet formed on the outermost layer on the opposite side of the carrier film and the ceramic green sheet formed on the outermost layer on the side adjacent to the carrier film are adjacent to each other. The manufacturing method of Claim 1 which laminates | stacks the said several laminated body unit so that it may overlap.   In the laminated sheet forming step, the ceramic green sheet positioned in the outermost layer has a thickness after firing of other ceramic green sheets laminated so that the thickness after firing is adjacent to the ceramic green sheet in the lamination step. The manufacturing method of Claim 1 or 2 formed in thickness which becomes thickness corresponding to the space | interval of the said internal electrode layers which adjoin together. A laminated body in which ceramic layers and internal electrode layers are alternately laminated, and via electrodes formed so as to connect a plurality of different internal electrode layers inside the laminated body,
The via electrode has a protruding portion that protrudes in a direction parallel to the main surface of the internal electrode layer without contacting the internal electrode layer at a portion where the position of the stacked body in the stacking direction is different from the internal electrode layer. Has a multilayer ceramic electronic component.

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