Manufacturing method for surface-mount electronic components

Abstract

A method for manufacturing a surface-mounted electronic component, the method comprising: an element body preparing step for preparing a cuboidal electronic component element body 10 including an inner conductor 16 and having a first main surface 10a and a second main surface 10b opposing each other in a height direction T, a first side surface 10c and a second side surface 10d opposing each other in a width direction W, and a first end surface 10e and a second end surface 10f opposing each other in a length direction L; an element body disposing step for disposing the electronic component element body 10 such that the first end surface 10e and the second end surface 10f respectively face upward and downward; and an electrode forming step for screen-printing an electrode paste 61 on the first end surface 10e and the first main surface 10a while causing the electronic component element body 10 to fall on the second main surface 10b side, and forming external electrodes 110, 210 on the first end surface 10e and the first main surface 10a.

Description

Technical Field

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[0005]

[0001] The present invention relates to a method for manufacturing a surface-mounted electronic component.

Background Art

[0002] Patent Documents 1 and 2 describe a method of forming external electrodes of an electrolytic capacitor by applying an electrode paste by screen printing to the end face and the surrounding bottom face, upper face, and side face of a resin molded body in which a plurality of capacitor elements are encapsulated with a sealing resin.

[0003] Patent Document 3 describes a method of forming external electrodes of an electrolytic capacitor by applying an electrode paste by screen printing to the end face and the bottom face of a resin molded body in which a plurality of capacitor elements are encapsulated with a sealing resin.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0005] In an electrolytic capacitor, internal electrodes of an anode and a cathode are drawn out to both end faces of a resin molded body, and the bottom face serves as a mounting face. Therefore, it is sufficient to be able to print an electrode paste on at least the end face and the bottom face of the resin molded body.

[0006] ]>However, in the methods described in Patent Documents 1 and 2, the electrode paste is also applied to the upper face and the side face of the resin molded body (electronic component element body), which increases the cost accordingly.

[0007] Furthermore, the method described in Patent Document 3 requires screen printing on both the end face and the bottom face of the resin molded body, resulting in poor productivity.

[0008] Furthermore, in the methods described in Patent Documents 1 to 3, the coverage of the electrode paste at the edge of the resin molded body is insufficient, which may result in insufficient conductivity of the external electrode between the end surface and the bottom surface.

[0009] The present invention was made to solve the above problems and aims to provide a method for manufacturing surface-mount electronic components that allows for the easy formation of external electrodes with excellent coverage at the edges of the electronic component body. [Means for solving the problem]

[0010] The present invention provides a method for manufacturing a surface-mount electronic component, comprising: a body preparation step of preparing a rectangular parallelepiped electronic component body having an internal conductor and having a first main surface and a second main surface opposite to each other in the height direction, a first side surface and a second side surface opposite to each other in the width direction, and a first end surface and a second end surface opposite to each other in the length direction; a body placement step of arranging the electronic component body so that the first end surface and the second end surface face up and down, respectively; and an electrode formation step of screen printing electrode paste onto the first end surface and the first main surface while tilting the electronic component body toward the second main surface, thereby forming external electrodes on the first end surface and the first main surface. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a method for manufacturing surface-mount electronic components that allows for the easy formation of external electrodes with excellent coverage at the edges of the electronic component body. [Brief explanation of the drawing]

[0012] [Figure 1] Figure 1 is a schematic perspective view showing an example of an electronic component body according to Embodiment 1 of the present invention. [Figure 2]Figure 2 is an example of a cross-sectional view of the electronic component shown in Figure 1, specifically an AA cross-section, and shows the resin molded body that constitutes an electrolytic capacitor. [Figure 3] Figure 3 is another example of a cross-sectional view of the electronic component shown in Figure 1, specifically an AA cross-section, and shows a resin molded body that constitutes an electrolytic capacitor. [Figure 4] Figure 4 is another example of a cross-sectional view of the electronic component shown in Figure 1, specifically the AA cross-section, and shows the laminate that constitutes a multilayer ceramic capacitor. [Figure 5] Figure 5 is a schematic exploded perspective view showing an example of the process of arranging an electronic component base in a manufacturing method for surface-mount electronic components according to Embodiment 1 of the present invention. [Figure 6] Figure 6 is a schematic cross-sectional view showing an example of the process of arranging an electronic component base in a manufacturing method for surface-mount electronic components according to Embodiment 1 of the present invention. [Figure 7] Figure 7 is a schematic perspective view showing an example of the process of forming external electrodes on the electronic component body shown in Figure 5. [Figure 8] Figure 8 is a schematic cross-sectional view showing an example of the process (mesh coating) for forming external electrodes on the electronic component base shown in Figure 6. [Figure 9] Figure 9 is a schematic cross-sectional view showing an example of the process (screen printing) for forming external electrodes on the electronic component base shown in Figure 8. [Figure 10] Figure 10 is a schematic cross-sectional view showing an example of the process (after screen printing) of forming external electrodes on the electronic component base shown in Figure 8. [Figure 11] Figure 11 is a schematic perspective view showing an example of a surface-mount electronic component manufactured by the manufacturing method of a surface-mount electronic component according to Embodiment 1 of the present invention. [Figure 12] Figure 12 is a first side view of the surface-mount electronic component shown in Figure 11. [Figure 13] Figure 13 is a second side view of the surface-mount electronic component shown in Figure 11. [Figure 14] Figure 14 is a schematic cross-sectional view showing an example of the process of arranging an electronic component in a manufacturing method for surface-mount electronic components according to Embodiment 2 of the present invention. [Figure 15] FIG. 15 is a cross-sectional view schematically showing an example of a process (first screen printing) of forming external electrodes on the electronic component body shown in FIG. 14. [Figure 16] FIG. 16 is a cross-sectional view schematically showing an example of a process (after the first screen printing) of forming external electrodes on the electronic component body shown in FIG. 14. [Figure 17] FIG. 17 is a cross-sectional view schematically showing an example of a process (second mesh coat) of forming external electrodes on the electronic component body shown in FIG. 16. [Figure 18] FIG. 18 is a perspective view schematically showing an example of a process (second screen printing) of forming external electrodes on the electronic component body shown in FIG. 17. [Figure 19] FIG. 19 is a perspective view schematically showing an example of a process (after the second screen printing) of forming external electrodes on the electronic component body shown in FIG. 17. [Figure 20] FIG. 20 is a perspective view schematically showing an example of a surface-mounted electronic component produced by the manufacturing method of the surface-mounted electronic component according to Embodiment 2 of the present invention. [[ID=IS]] [Figure 21] FIG. 21 is a first side view of the surface-mounted electronic component shown in FIG. 20. [Figure 22] FIG. 22 is a second side view of the surface-mounted electronic component shown in FIG. 20. BEST MODE FOR CARRYING OUT THE INVENTION

[0013] Hereinafter, a method for manufacturing a surface-mounted electronic component of the present invention will be described. However, the present invention is not limited to the following configurations, and can be appropriately modified and applied without changing the gist of the present invention. In addition, a combination of two or more of the individual desirable configurations described below is also the present invention.

[0014] [Embodiment 1] First, a method for manufacturing a surface-mounted electronic component according to Embodiment 1 of the present invention will be described.

[0015] (Body preparation process) Figure 1 is a schematic perspective view showing an example of an electronic component body according to Embodiment 1 of the present invention.

[0016] As shown in Figure 1, first, a plurality of rectangular parallelepiped electronic component bodies 10 are prepared. Each electronic component body 10 has a plurality of internal conductors 16 and has a first main surface 10a and a second main surface 10b that are opposite in the height direction T, a first side surface 10c and a second side surface 10d that are opposite in the width direction W, and a first end surface 10e and a second end surface 10f that are opposite in the length direction L. The first main surface 10a is the side that will become the mounting surface for the surface mount type electronic component manufactured from the electronic component body 10.

[0017] As described above, the electronic component body 10 has a roughly rectangular parallelepiped shape, but the corners and edges may be rounded. The corners are the parts where three faces of the electronic component body 10 intersect, and the edges are the parts where two faces of the electronic component body 10 intersect.

[0018] The areas of the first main surface 10a and the second main surface 10b may be substantially the same as, or different from, the areas of the first side surface 10c and the second side surface 10d.

[0019] Each internal conductor 16 is exposed on either the first end face 10e or the second end face 10f.

[0020] Suitable examples of surface-mount electronic components manufactured by the manufacturing method of this embodiment include electrolytic capacitors and multilayer ceramic electronic components.

[0021] First, let's explain the internal structure of the electronic component when manufacturing electrolytic capacitors.

[0022] Figure 2 is an example of a cross-sectional view of the electronic component shown in Figure 1, specifically an AA cross-section, and shows the resin molded body that constitutes an electrolytic capacitor.

[0023] In this case, as shown in Figure 2, the electronic component body 10 is a resin molded body 20 and has a plurality of capacitor elements 21 and a sealing resin 22 that seals the plurality of capacitor elements 21.

[0024] In this case, an inner plating layer may be formed on the first end face 10e and the second end face 10f, respectively. The inner plating layer may have a Ni plating layer and an Ag plating layer on the Ni plating layer.

[0025] If the internal conductor 16 contains Al, it is preferable that the Ni plating layer electrically connected to the internal conductor 16 be formed by zincate treatment. That is, the surface of the exposed internal conductor 16 is alkali-etched to remove the oxide film of the internal conductor 16, and then zinc plating is performed. Next, the Ni plating layer is formed by displacement plating with electroless Ni plating.

[0026] The capacitor element 21 includes an anode 23 having a dielectric layer 25 on its surface and a cathode 27 facing the anode 23 as its internal conductor 16.

[0027] Multiple capacitor elements 21 are stacked to form a laminate 28, and the periphery of the laminate 28 is sealed with a sealing resin 22 to form a resin molded body 20. In the laminate 28, the stacked capacitor elements 21 may be joined to each other via a conductive adhesive (not shown).

[0028] The first external electrode, described later, is electrically connected to the anode 23 exposed from the first end face 10e. The second external electrode, also described later, is electrically connected to the cathode 27 exposed from the second end face 10f.

[0029] The anode 23 has a valve-acting metal foil 23a at its center and a porous layer (not shown), such as an etching layer, on its surface. A dielectric layer 25 is provided on the surface of the porous layer.

[0030] Examples of valve metals include elemental metals such as aluminum, tantalum, niobium, titanium, zirconium, magnesium, and silicon, or alloys containing these metals. Among these, aluminum or aluminum alloys are preferred.

[0031] The shape of the valve metal is not particularly limited, but it is preferably flat and more preferably foil-shaped. Furthermore, the porous layer is preferably an etched layer that has been etched with hydrochloric acid or the like.

[0032] The anode 23 is led out to the first end face 10e and electrically connected to the first external electrode.

[0033] The dielectric layer 25 is preferably made of an oxide film of the valve metal. For example, when aluminum foil is used as the valve metal substrate, an oxide film that becomes the dielectric layer 25 can be formed by anodic oxidation in an aqueous solution containing boric acid, phosphoric acid, adipic acid, or their sodium salts, ammonium salts, etc.

[0034] The dielectric layer 25 is formed along the surface of the porous layer, thereby creating pores (recesses).

[0035] The cathode 27 is formed by laminating a solid electrolyte layer 27a formed on the dielectric layer 25, a conductive layer 27b formed on the solid electrolyte layer 27a, and a cathode extraction layer 27c formed on the conductive layer 27b.

[0036] Since a solid electrolyte layer 27a is provided as part of the cathode 27, the resulting electrolytic capacitor can be described as a solid electrolytic capacitor.

[0037] Examples of materials constituting the solid electrolyte layer 27a include conductive polymers with pyrroles, thiophenes, anilines, etc. as a backbone. Examples of conductive polymers with thiophenes as a backbone include PEDOT [poly(3,4-ethylenedioxythiophene)], which may be PEDOT:PSS, a compound formed by combining PEDOT with polystyrene sulfonic acid (PSS) as a dopant.

[0038] The solid electrolyte layer 27a is formed, for example, by using a processing solution containing a monomer such as 3,4-ethylenedioxythiophene to form a polymerized film such as poly(3,4-ethylenedioxythiophene) on the surface of the dielectric layer 25, or by applying a dispersion of a polymer such as poly(3,4-ethylenedioxythiophene) to the surface of the dielectric layer 25 and drying it. It is preferable to form an inner solid electrolyte layer that fills the pores (recesses) and then form an outer solid electrolyte layer that covers the entire dielectric layer 25.

[0039] The solid electrolyte layer 27a can be formed in a predetermined area by applying the above-mentioned processing solution or dispersion onto the dielectric layer 25 by sponge transfer, screen printing, spray coating, dispenser, inkjet printing, or the like.

[0040] The conductive layer 27b is provided to electrically and mechanically connect the solid electrolyte layer 27a and the cathode extraction layer 27c. Preferably, it is a carbon layer, graphene layer, or silver layer formed by applying a conductive paste such as carbon paste, graphene paste, or silver paste. Alternatively, it may be a composite layer in which a silver layer is provided on top of a carbon layer or graphene layer, or a mixed layer formed by mixing carbon paste or graphene paste with silver paste.

[0041] The conductive layer 27b can be formed on the solid electrolyte layer 27a by forming a conductive paste, such as carbon paste, on the solid electrolyte layer 27a using sponge transfer, screen printing, spray coating, a dispenser, inkjet printing, or the like. It is preferable to laminate the cathode extraction layer 27c in the next step while the conductive layer 27b is still viscous before drying.

[0042] The cathode extraction layer 27c can be formed from a metal foil or a printed electrode layer.

[0043] In the case of metal foil, it is preferable that it consists of at least one metal selected from the group consisting of Al, Cu, Ag, and alloys mainly composed of these metals.

[0044] Furthermore, metal foils with a carbon coating or titanium coating applied to the surface by film deposition methods such as sputtering or vapor deposition may also be used. It is more preferable to use carbon-coated aluminum foil.

[0045] In the case of a printed electrode layer, the cathode extraction layer 27c can be formed in a predetermined area by forming an electrode paste on the conductive layer 27b using methods such as sponge transfer, screen printing, spray coating, dispenser, or inkjet printing. The electrode paste is preferably composed mainly of Ag, Cu, or Ni. When the cathode extraction layer 27c is a printed electrode layer, the thickness of the printed electrode layer can be made thinner than when using metal foil.

[0046] The cathode extraction layer 27c is drawn out to the second end face 10f of the resin molded body 20 and electrically connected to the second external electrode.

[0047] The sealing resin 22 contains at least a resin, preferably a resin and a filler. As the resin, it is preferable to use, for example, epoxy resin, phenolic resin, polyimide resin, silicone resin, polyamide resin, or liquid crystal polymer. The sealing resin 22 can be in the form of a solid resin or a liquid resin. As the filler, it is preferable to use, for example, silica particles, alumina particles, or metal particles. It is even more preferable to use a material containing silica particles in both the solid epoxy resin and the phenolic resin.

[0048] As for the molding method of the resin molded body 20, when a solid encapsulant is used, it is preferable to use a resin mold such as a compression mold or a transfer mold, and more preferably a compression mold. When a liquid encapsulant is used, it is preferable to use a molding method such as a dispensing method or a printing method. It is preferable to encapsulate the laminated body 28 of the capacitor element 21, consisting of an anode 23, a dielectric layer 25, and a cathode 27, with a encapsulating resin 22 using a compression mold to form the resin molded body 20.

[0049] A support substrate 29 is provided at the bottom of the resin molded body 20, and the bottom surface of the support substrate 29 is the first main surface 10a of the electronic component body 10.

[0050] The support substrate 29 is provided to integrate a laminate 28 formed by stacking multiple capacitor elements 21, and is preferably made of a glass epoxy substrate.

[0051] Figure 3 is another example of a cross-sectional view of the electronic component shown in Figure 1, specifically an AA cross-section, and shows a resin molded body that constitutes an electrolytic capacitor.

[0052] As shown in Figure 3, the electronic component body 10 does not necessarily have a support substrate at its bottom. In this case, the first main surface 10a of the electronic component body 10 (resin molded body 20) is the surface of the sealing resin 22.

[0053] The electronic component body 10 for electrolytic capacitors described above is used in solid electrolytic capacitors having a solid electrolyte layer. However, the surface-mount electronic component manufactured by the manufacturing method of this embodiment may be an electrolytic capacitor using a liquid electrolyte instead of a solid electrolyte, or an electrolytic capacitor using a liquid electrolyte together with a solid electrolyte.

[0054] Furthermore, while it is preferable for the laminate containing the capacitor element to contain multiple capacitor elements, it may also contain only one capacitor element.

[0055] Next, we will describe multilayer ceramic electronic components as another example of surface-mount electronic components manufactured by the manufacturing method of this embodiment.

[0056] In this case, the electronic component body is preferably a rectangular parallelepiped laminate in which at least one of a dielectric ceramic layer, a magnetic ceramic layer, a piezoelectric ceramic layer, or a semiconductor ceramic layer is laminated with an internal electrode layer as an internal electrode.

[0057] Examples of multilayer ceramic electronic components include multilayer ceramic capacitors, multilayer coils, multilayer thermistors, multilayer varistors, multilayer LC filters, and multilayer piezoelectric filters.

[0058] This section describes the internal structure of the electronic component body used when manufacturing multilayer ceramic capacitors.

[0059] Figure 4 is another example of a cross-sectional view of the electronic component shown in Figure 1, specifically the AA cross-section, and shows the laminate that constitutes a multilayer ceramic capacitor.

[0060] In this case, as shown in Figure 4, the electronic component body 10 is a laminate 30 in which a dielectric ceramic layer 31 and internal electrode layers 32 and 33 are stacked.

[0061] The internal electrode layers 32 and 33 are internal conductors 16, with the internal electrode layer 32 connected to the first external electrode and the internal electrode layer 33 connected to the second external electrode.

[0062] The dielectric ceramic layer 31 contains a dielectric ceramic such as barium titanate. The dielectric ceramic layer can be obtained by forming a dielectric slurry containing a dielectric ceramic and an organic solvent into a sheet.

[0063] The internal electrode layers 32 and 33 can be obtained by printing an electrode paste containing a conductive component. Preferably, the internal electrode layers 32 and 33 are Ni electrode layers using Ni as the conductive component.

[0064] Alternatively, an Ag electrode layer, a Pd electrode layer, or a Cu electrode layer may be used instead of the Ni electrode layer.

[0065] (Body arrangement process) Figure 5 is a schematic exploded perspective view showing an example of the process of arranging an electronic component in the manufacturing method of a surface-mount electronic component according to Embodiment 1 of the present invention. Figure 6 is a schematic cross-sectional view showing an example of the process of arranging an electronic component in the manufacturing method of a surface-mount electronic component according to Embodiment 1 of the present invention.

[0066] As shown in Figures 5 and 6, the electronic component bodies 10 are then positioned such that the first end face 10e and the second end face 10f are facing in the vertical direction.

[0067] The electronic component bodies 10 are arranged at equal intervals in mutually orthogonal directions D1 and D2 in the horizontal plane.

[0068] In the component placement process, it is preferable to place each electronic component 10 on an adhesive sheet 40 containing silicone resin. This fixes each electronic component 10 on the adhesive sheet 40, making it possible to print the electrode paste more stably during the screen printing process described later.

[0069] The adhesive sheet 40 is made by processing a material in which an adhesive is mixed with silicone resin, which is the main component, into a sheet shape, and is a substrate (tack sheet) that has adhesive properties and elasticity (cushioning properties). Therefore, each electronic component body 10 placed on the adhesive sheet 40 can withstand loads from the vertical direction.

[0070] The thickness of the adhesive sheet 40 is preferably 0.1 mm or more and 10 mm or less, more preferably 0.5 mm or more and 5 mm or less, and even more preferably 1 mm or more and 3 mm or less.

[0071] The adhesive strength of the adhesive sheet 40 is preferably 25N or higher. If it is less than 25N, the electronic component body 10 may rise in the direction of the electrode paste (screen printing plate) and detach from the adhesive sheet 40 during screen printing, as described later. Here, the adhesive strength of the adhesive sheet 40 is measured as the interfacial fracture strength by a peel test (90° peel test).

[0072] The hardness (rubber hardness) of the adhesive sheet 40 is preferably between 20° and 40°. If it exceeds 40°, the electronic component body 10 will not be easily absorbed by the adhesive sheet 40, which may cause the screen printing plate to tear at the contact point with the squeegee during screen printing, as described later. Here, the hardness (rubber hardness) of the adhesive sheet 40 is measured using a Type A durometer (hardness tester Type A) in accordance with JIS K 6253.

[0073] The in-plane thickness variation of the adhesive sheet 40 is preferably within 30 μm. If it exceeds 30 μm, the thickness of the electrode paste coating applied to the electronic component body 10 during screen printing, as described later, may vary depending on the electronic component body 10. Here, the film thickness of the adhesive sheet 40 is measured using a thickness gauge.

[0074] From a similar viewpoint, it is preferable in the component placement process to place the electronic component base 10 in each of the multiple through holes 51 of the jig 50, which is provided with through holes 51 in the vertical direction.

[0075] Specifically, first, the jig 50 is placed on the adhesive sheet 40, and then the electronic component body 10 is placed in each through hole 51 of the jig 50 so that the first end face 10e and the second end face 10f are facing in the vertical direction, respectively.

[0076] Here, each electronic component body 10 is positioned such that there is a predetermined gap D between the second main surface 10b and the jig 50 (see Figure 6). On the other hand, there may or may not be such a gap between the first main surface 10a of each electronic component body 10 and the jig 50.

[0077] The material of the jig 50 is not particularly limited as long as it is solvent-resistant, but it is preferably a rigid body that does not have adhesive properties or elasticity. Specifically, examples include glass epoxy resin, epoxy resin, and metal.

[0078] As shown in Figure 6, the jig 50 has an inclined surface 52a at its top, which comes into contact with the corresponding electronic component body 10 during screen printing, as described later.

[0079] Each inclined surface 52a is located on the upper part of the wall surface that forms the through hole 51, on the side of the second main surface 10b of the electronic component body 10.

[0080] Furthermore, a slope 52b is provided on the upper part of the wall surface forming each through-hole 51, on the side of the first main surface 10a of the electronic component body 10.

[0081] Both slopes 52a and 52b are flat inclined surfaces, and as shown in Figure 6, the opening width of each through-hole 51 widens from bottom to top in the region where the pair of slopes 52a and 52b are arranged.

[0082] The size of the gap D between the second main surface 10b and the jig 50 is set so that the electronic component body 10, which will be tilted during screen printing as described later, will follow the slope 52a.

[0083] In this embodiment, the inclined surface 52b does not need to be provided. For example, the upper part of the wall surface forming each through-hole 51, on the side of the first main surface 10a of the electronic component body 10, may be a vertical surface.

[0084] (Electrode formation process) Figure 7 is a schematic perspective view showing an example of the process of forming external electrodes on the electronic component base shown in Figure 5. Figure 8 is a schematic cross-sectional view showing an example of the process of forming external electrodes (mesh coating) on ​​the electronic component base shown in Figure 6.

[0085] Next, an electrode paste is printed onto multiple electronic component bodies 10 using a mesh screen printing machine.

[0086] First, as shown in Figures 7 and 8, a mesh screen 60 is placed on the electronic component body 10 as a screen printing plate, and electrode paste 61 is applied to the mesh screen 60. A predetermined gap (clearance) is provided between the electronic component body 10 and the mesh screen 60. Then, squeegee 62 is moved on the mesh screen 60 in the squeegeeing direction (the direction in which the squeegee 62 moves) to perform squeegeeing. The height of the squeegee 62 is adjusted so that at this stage, the mesh screen 60 and electrode paste 61 do not come into contact with the electronic component body 10, and the electrode paste 61 accumulates on the mesh screen 60. Then, a portion of the electrode paste 61 accumulated on the mesh screen 60 is allowed to protrude onto the lower surface of the mesh screen 60 (the surface opposite to the squeegeeed surface).

[0087] Figure 9 is a schematic cross-sectional view showing an example of the process (screen printing) for forming external electrodes on the electronic component base shown in Figure 8. Figure 10 is a schematic cross-sectional view showing an example of the process (after screen printing) for forming external electrodes on the electronic component base shown in Figure 8.

[0088] Next, as shown in Figure 9, the electrode paste 61 is screen printed onto the first end face 10e and the first main face 10a while tilting the electronic component body 10 toward the second main face 10b, thereby applying the electrode paste 61 to the first end face 10e and the first main face 10a. Then, the electrode paste 61 is heat-cured to form external electrodes on the first end face 10e and the first main face 10a.

[0089] More specifically, first, electrode paste 61 is applied to the mesh screen 60, and then squeegee 62 is moved on the mesh screen 60 to perform squeegeeing. At this time, the height of the squeegee 62 is adjusted so that the tip of the squeegee 62 is slightly lower than the first end face 10e of the electronic component body 10. Then, just before the squeegee 62 arrives, the mesh screen 60, which is pressed downward by the squeegee 62, comes into contact with the first end face 10e of the electronic component body 10, thereby applying electrode paste 61 to the entire first end face 10e. After that, when the squeegee 62 arrives, the upper part of the electronic component body 10 is pushed in the squeegeeing direction. Then, when the shear stress generated at the interface between the electronic component body 10 and the adhesive sheet 40 exceeds a threshold, a gap D exists between the second main surface 10b and the jig 50. As a result, the electronic component body 10 begins to rotate around the ridge 11bf where the second main surface 10b and the second end surface 10f intersect, and the electronic component body 10 falls over until it contacts the jig 50 (especially the inclined surface 52a). At this time, the mesh screen 60 remains in contact with the electronic component body 10 even while it is falling over, and electrode paste 61 is applied to the first main surface 10a of the electronic component body 10 (especially a part of its first end surface 10e side).

[0090] In this way, as shown in Figure 10, the electrode paste 61 is applied not only to the first end face 10e of the electronic component body 10, but also to the first main surface 10a of the electronic component body 10 simultaneously. Furthermore, since the film thickness of the electrode paste 61 increases on the ridge portion 11ae where the first end face 10e and the first main surface 10a intersect, sufficient film thickness (G dimension) of the external electrode can be secured at the edge portion (especially the ridge portion 11ae) of the electronic component body 10. Therefore, according to this embodiment, it is possible to easily form an external electrode with excellent coverage at the edge portion of the electronic component body 10.

[0091] Furthermore, since it is not necessary to apply electrode paste 61 to all four surfaces, the first main surface 10a, the second main surface 10b, the first side surface 10c, and the second side surface 10d, costs can be reduced. In addition, since no external electrodes are formed on the second main surface 10b, i.e., the top surface, the surface-mount electronic component, which is the finished product, is less likely to short-circuit even if it comes into contact with other components or the lid.

[0092] Furthermore, during the screen printing process described above, the electrode paste 61 may also be applied to the first side surface 10c and the second side surface 10d of the electronic component body 10 (particularly the region near the corner where the first side surface 10c and the second side surface 10d intersect with the first end surface 10e and the first main surface 10a, respectively).

[0093] Alternatively, unlike the method described above, it is also possible to perform screen printing with the electronic component body tilted at an angle from the beginning. However, in this case, the electrode paste will not be applied to the entire first end face of the electronic component body, but only to the portion of the first main surface side of the first end face.

[0094] The amount of electrode paste 61 applied to the first main surface 10a of the electronic component body 10 (how far the electrode paste 61 is applied from the ridge portion 11ae to the first main surface 10a) can be controlled by the tilt angle of the electronic component body 10 during screen printing. A larger tilt angle of the electronic component body 10 results in a larger amount of electrode paste 61 being applied to the first main surface 10a. As a result, the dimensions (E dimension) of the external electrodes on the first main surface 10a become larger.

[0095] More specifically, during screen printing, the maximum inclination angle θ1 of the electronic component body 10 with respect to the vertical is preferably 10° or more and 45° or less.

[0096] Furthermore, as described above, it is preferable to tilt the electronic component body 10 until it contacts the jig 50 (especially the inclined surface 52a) during screen printing. This stabilizes the maximum tilt angle of the electronic component body 10, making it possible to print the electrode paste more stably.

[0097] Furthermore, the angle φ1 made by the inclined surface 52a with respect to the vertical direction is preferably between 20° and 45°. This makes it easy to set the maximum inclination angle θ1 of the electronic component body 10 within the above range.

[0098] While there are no particular limitations on the screen printing plate used, from a cost standpoint, it is preferable to use a mesh screen 60 for screen printing, as described above.

[0099] The mesh screen 60 can be made of wires woven into a mesh pattern, for example, from stainless steel such as SUS or high-tensile resin such as polyester.

[0100] The electrode paste 61 used is not particularly limited, and any paste that has been used for forming external electrodes by conventional screen printing can be used, but metal paste and conductive polymer paste are particularly preferred.

[0101] Preferably, the metal paste contains conductive components (metal nanoparticles) such as Ag, Cu, and Ni, and an insulating resin component that acts as a binder.

[0102] The conductive polymer paste is preferably one that contains a conductive component (conductive polymer) such as polythiophene resin, polyacetylene resin, polyaniline resin, and polypyrrole resin, and a resin component which is a binder component. It is preferable that the conductive polymer contains a dopant such as polystyrene sulfonic acid to improve conductivity.

[0103] After forming external electrodes on the first end face 10e and the first main surface 10a, the same screen printing is performed on the second end face 10f side of the electronic component body 10, thereby screen printing the electrode paste 61 onto the second end face 10f and the first main surface 10a as well, and forming external electrodes on the second end face 10f and the first main surface 10a.

[0104] Furthermore, after forming the electrode layer with the electrode paste 61, an outer plating layer may be formed on the electrode layer. The outer plating layer may have a Ni plating layer and a Sn plating layer on the Ni plating layer.

[0105] (Surface mount electronic components) Figure 11 is a schematic perspective view showing an example of a surface-mount electronic component manufactured by the manufacturing method of a surface-mount electronic component according to Embodiment 1 of the present invention. Figure 12 is a first side view of the surface-mount electronic component shown in Figure 11. Figure 13 is a second side view of the surface-mount electronic component shown in Figure 11.

[0106] As shown in Figures 11, 12, and 13, the surface-mount electronic component 100 manufactured by the manufacturing method of this embodiment comprises an electronic component body 10, a first external electrode 110, and a second external electrode 120.

[0107] The first external electrode 110 is formed by being integrated with the first end face 10e and the first main face 10a of the electronic component body 10. Therefore, the first external electrode 110 is L-shaped in cross-section parallel to the first side surface 10c.

[0108] Furthermore, the first external electrode 110 may also be formed integrally with the first side surface 10c and the second side surface 10d. More specifically, as shown in Figure 12, the first external electrode 110 may also be formed on the first side surface 10c near the corner 12ace where the first end surface 10e, the first main surface 10a, and the first side surface 10c intersect, or as shown in Figure 13, it may also be formed on the second side surface 10d near the corner 12ade where the first end surface 10e, the first main surface 10a, and the second side surface 10d intersect.

[0109] Furthermore, the first external electrode 110 may also be formed on the ridge portion (especially the rounded ridge portion) where the first end face 10e intersects with the second main face 10b, the first side surface 10c, or the second side surface 10d.

[0110] The second external electrode 120 is formed by being integrated with the second end face 10f and the first main face 10a of the electronic component body 10. Therefore, the second external electrode 120 is L-shaped in cross-section parallel to the first side surface 10c.

[0111] Furthermore, the second external electrode 120 may also be formed integrally with the first side surface 10c and the second side surface 10d. More specifically, as shown in Figure 12, the second external electrode 120 may also be formed on the first side surface 10c near the corner 12acf where the second end surface 10f, the first main surface 10a, and the first side surface 10c intersect, or as shown in Figure 13, it may also be formed on the second side surface 10d near the corner 12adf where the second end surface 10f, the first main surface 10a, and the second side surface 10d intersect.

[0112] Furthermore, the second external electrode 120 may also be formed on the ridge portion (especially the rounded ridge portion) where the second end face 10f intersects with the second main face 10b, the first side surface 10c, or the second side surface 10d.

[0113] Since the first external electrode 110 is formed by the screen printing described above, as shown in Figures 12 and 13, a sufficient film thickness G1 (G dimension) can be secured at the edge portion of the electronic component body 10, particularly at the ridge portion 11ae where the first end face 10e and the first main face 10a intersect. Similarly, for the second external electrode 120, as shown in Figures 12 and 13, a sufficient film thickness G2 (G dimension) can be secured at the edge portion of the electronic component body 10, particularly at the ridge portion 11af where the second end face 10f and the first main face 10a intersect.

[0114] Furthermore, the dimensions E1 and E2 (E dimension) of the first external electrode 110 and the second external electrode 120 on the first main surface 10a are controlled by the inclination angle of the electronic component body 10 during the screen printing process.

[0115] The type of surface-mount electronic component 100 manufactured by the manufacturing method of this embodiment is not particularly limited, but an electrolytic capacitor is preferred. This is because a large space can be secured on the second main surface 10b, where the first external electrode 110 and the second external electrode 120 are not formed, for printing a mark indicating the polarity of the electrolytic capacitor.

[0116] [Embodiment 2] Next, a method for manufacturing a surface-mount electronic component according to Embodiment 2 of the present invention will be described. This embodiment is substantially the same as Embodiment 1, except that screen printing is performed twice per end face in two directions while the electronic component body is tilted.

[0117] Figure 14 is a schematic cross-sectional view showing an example of the process of arranging an electronic component in a manufacturing method for surface-mount electronic components according to Embodiment 2 of the present invention.

[0118] As shown in Figure 14, similar to Embodiment 1, each electronic component body 10 is arranged so that the first end face 10e and the second end face 10f are facing in the vertical direction. However, each electronic component body 10 is arranged so that there is a gap D not only between the second main surface 10b and the jig 50, but also between the first main surface 10a and the jig 50. In other words, in this embodiment, compared to Embodiment 1, the opening width of each through hole 51 is wider by the amount of the gap D on the first main surface 10a side.

[0119] Figure 15 is a schematic cross-sectional view showing an example of the process of forming external electrodes on the electronic component base shown in Figure 14 (first screen printing). Figure 16 is a schematic cross-sectional view showing an example of the process of forming external electrodes on the electronic component base shown in Figure 14 (after the first screen printing).

[0120] Next, similar to Embodiment 1, after accumulating electrode paste 61 on the mesh screen 60 so that the mesh screen 60 and electrode paste 61 do not come into contact with the electronic component body 10 (see Figure 8), as shown in Figures 15 and 16, the electrode paste 61 is screen printed onto the first end face 10e and the first main face 10a while tilting the electronic component body 10 toward the second main face 10b side.

[0121] Figure 17 is a schematic cross-sectional view showing an example of the process of forming external electrodes (second mesh coating) on ​​the electronic component body shown in Figure 16.

[0122] Subsequently, as shown in Figure 17, each electronic component body 10 is rearranged (made upright) so that the first end face 10e and the second end face 10f are facing in the vertical direction, respectively. Then, the height of the squeegee 62 is adjusted (made higher) so that the mesh screen 60 and electrode paste 61 do not come into contact with the electronic component body 10, and the electrode paste 61 accumulates on the mesh screen 60.

[0123] Figure 18 is a schematic perspective view showing an example of the process of forming external electrodes on the electronic component base shown in Figure 17 (second screen printing). Figure 19 is a schematic perspective view showing an example of the process of forming external electrodes on the electronic component base shown in Figure 17 (after the second screen printing).

[0124] Next, as shown in Figures 18 and 19, similar to Embodiment 1, the electrode paste 61 is screen printed onto the first end face 10e and the second main face 10b while tilting the electronic component body 10 toward the first main face 10a (opposite side from the first screen printing), thereby coating the electrode paste 61 onto the first end face 10e and the second main face 10b. This second screen printing is performed without drying or heat-curing the electrode paste 61 applied in the first screen printing. Then, external electrodes are formed on the first end face 10e, the first main face 10a, and the second main face 10b by heat-curing the electrode paste 61.

[0125] During the second screen printing, the maximum inclination angle θ2 of the electronic component body 10 with respect to the vertical is preferably between 10° and 45°.

[0126] The maximum tilt angle θ2 of the electronic component body 10 may be substantially the same as the maximum tilt angle θ1 of the electronic component body 10 during the first screen printing.

[0127] The angle φ2 made by the inclined plane 52b with respect to the vertical can be set as appropriate, but it is preferably between 20° and 45°.

[0128] The angle φ2 formed by the slope 52b may be substantially the same as the angle φ1 formed by the opposite slope 52a.

[0129] Furthermore, during the second screen printing described above, the electrode paste 61 may also be applied to the first side surface 10c and the second side surface 10d of the electronic component body 10 (especially the areas near the corners where the first side surface 10c and the second side surface 10d intersect with the first end surface 10e and the second main surface 10b, respectively).

[0130] (Surface mount electronic components) Figure 20 is a schematic perspective view showing an example of a surface-mount electronic component manufactured by the manufacturing method of a surface-mount electronic component according to Embodiment 2 of the present invention. Figure 21 is a first side view of the surface-mount electronic component shown in Figure 20. Figure 22 is a second side view of the surface-mount electronic component shown in Figure 20.

[0131] As shown in Figures 20, 21, and 22, the surface-mount electronic component 200 manufactured by the manufacturing method of this embodiment has the same electronic component body 10 as in Embodiment 1, a first external electrode 210, and a second external electrode 220.

[0132] The first external electrode 210 is formed by being integrated with the first end face 10e, the first main face 10a, and the second main face 10b of the electronic component body 10. Therefore, the first external electrode 210 has a U-shape (C-shape) in a cross-section parallel to the first side surface 10c.

[0133] Furthermore, the first external electrode 210 may also be formed integrally with the first side surface 10c and the second side surface 10d. More specifically, as shown in Figure 21, the first external electrode 210 may also be formed on the first side surface 10c near the corner 12ace where the first end surface 10e, the first main surface 10a, and the first side surface 10c intersect, and near the corner 12bce where the first end surface 10e, the second main surface 10b, and the first side surface 10c intersect. Alternatively, as shown in Figure 22, it may also be formed on the second side surface 10d near the corner 12ade where the first end surface 10e, the first main surface 10a, and the second side surface 10d intersect, and near the corner 12bde where the first end surface 10e, the second main surface 10b, and the second side surface 10d intersect.

[0134] Furthermore, the first external electrode 210 may also be formed on the ridge portion (especially the rounded ridge portion) where the first end face 10e intersects with the first side surface 10c or the second side surface 10d.

[0135] The second external electrode 220 is formed by being integrated with the second end face 10f, the first main face 10a, and the second main face 10b of the electronic component body 10. Therefore, the second external electrode 220 has a U-shape (C-shape) in a cross-section parallel to the first side surface 10c.

[0136] Furthermore, the second external electrode 220 may also be formed integrally with the first side surface 10c and the second side surface 10d. More specifically, as shown in Figure 21, the second external electrode 220 may also be formed on the first side surface 10c near the corner 12acf where the second end surface 10f, the first main surface 10a, and the first side surface 10c intersect, and near the corner 12bcf where the second end surface 10f, the second main surface 10b, and the first side surface 10c intersect. Alternatively, as shown in Figure 22, it may also be formed on the second side surface 10d near the corner 12adf where the second end surface 10f, the first main surface 10a, and the second side surface 10d intersect, and near the corner 12bdf where the second end surface 10f, the second main surface 10b, and the second side surface 10d intersect.

[0137] Furthermore, the second external electrode 220 may also be formed on the ridge portion (especially the rounded ridge portion) where the second end face 10f intersects with the first side surface 10c or the second side surface 10d.

[0138] Since the first external electrode 210 is formed by the screen printing described above, as shown in Figures 21 and 22, sufficient film thickness G1 (G dimension) can be secured at the edge portion of the electronic component body 10, particularly at the ridge portion 11ae where the first end face 10e and the first main face 10a intersect, and at the ridge portion 11be where the first end face 10e and the second main face 10b intersect. Similarly, for the second external electrode 220, as shown in Figures 21 and 22, sufficient film thickness G2 (G dimension) can be secured at the edge portion of the electronic component body 10, particularly at the ridge portion 11af where the second end face 10f and the first main face 10a intersect, and at the ridge portion 11bf where the second end face 10f and the second main face 10b intersect.

[0139] Furthermore, the dimensions E1 and E2 (E dimensions) of the first external electrode 210 and the second external electrode 220 on the first main surface 10a, and the dimensions E3 and E4 (E dimensions) of the first external electrode 210 and the second external electrode 220 on the second main surface 10b, are controlled by the inclination angle of the electronic component body 10 during screen printing.

[0140] The type of surface-mount electronic component 200 manufactured by the manufacturing method of this embodiment is not particularly limited, but multilayer ceramic electronic components, and in particular multilayer ceramic capacitors, are preferred. This is because multilayer ceramic capacitors can be miniaturized, and in such cases, it is difficult to distinguish between the first main surface 10a and the second main surface 10b.

[0141] This specification discloses the following:

[0142] <1> A basic body preparation step of preparing a rectangular parallelepiped electronic component basic body having an internal conductor and having a first main surface and a second main surface opposite in the height direction, a first side surface and a second side surface opposite in the width direction, and a first end surface and a second end surface opposite in the length direction, A component arrangement step of arranging the electronic component body such that the first end face and the second end face each face in the vertical direction, A method for manufacturing a surface-mount electronic component, comprising: an electrode forming step of screen printing an electrode paste onto the first end face and the first main face while tilting the electronic component body toward the second main face side, thereby forming an external electrode on the first end face and the first main face.

[0143] <2> In the above-mentioned body placement step, the electronic component body is placed on an adhesive sheet containing silicone resin. <1> A method for manufacturing surface-mount electronic components as described above.

[0144] <3> During the aforementioned screen printing, the maximum inclination angle of the electronic component body with respect to the vertical direction is 10° or more and 45° or less. <1> or <2> A method for manufacturing surface-mount electronic components as described above.

[0145] <4> A mesh screen is used for the aforementioned screen printing. <1> from <3> A method for manufacturing a surface-mount electronic component as described in any one of the following.

[0146] <5> In the above-mentioned body placement step, the electronic component body is placed in the through-hole of a jig having through-holes in the vertical direction, During the screen printing process, the electronic component body is tilted until it comes into contact with the jig. <1> from <4> A method for manufacturing a surface-mount electronic component as described in any one of the following.

[0147] <6> The jig has an inclined surface at its upper end that contacts the electronic component body during screen printing, The angle of the slope with respect to the vertical is between 20° and 45°. <5> A method for manufacturing surface-mount electronic components as described above.

[0148] <7> The electrode paste comprises at least one of a metal paste and a conductive polymer paste. <1> from <6> A method for manufacturing a surface-mount electronic component as described in any one of the following.

[0149] <8> In the electrode formation step, after screen printing the electrode paste onto the first end face and the first main face, the electrode paste is screen printed onto the first end face and the second main face while tilting the electronic component body toward the first main face, thereby forming the external electrode on the first end face, the first main face, and the second main face. <1> from <7> A method for manufacturing a surface-mount electronic component as described in any one of the following.

[0150] <9> The aforementioned surface-mount electronic component is an electrolytic capacitor. <1> from <8> A method for manufacturing a surface-mount electronic component as described in any one of the following.

[0151] <10> The aforementioned surface-mount electronic component is a multilayer ceramic electronic component. <1> from <8> A method for manufacturing a surface-mount electronic component as described in any one of the following. [Explanation of symbols]

[0152] 10 Electronic Component Base 10a First main surface 10b Second main surface 10c 1st side 10d 2nd side 10e 1st end face 10f 2nd end face 11ae, 11af, 11be, 11bf ridgeline section 12ace, 12acf, 12ade, 12adf, 12bce, 12bcf, 12bde, 12bdf Corner 16 Inner conductor 20 Resin molded body 21 Capacitor element 22 Sealing resin 23 Anode 23a Valve metal foil 25 Dielectric layer 27 Cathode 27a Solid electrolyte layer 27b Conductive layer 27c Cathode extraction layer 28 Laminate 29 Support substrate 30-layer structure 31 Dielectric ceramic layer 32, 33 Internal electrode layer 40 Adhesive Sheets 50 jigs 51 Through hole 52a, 52b slope 60 Mesh Screen 61 Electrode Paste 62 squeegee 100, 200 surface mount electronic components 110, 210 1st external electrode 120, 220 2nd external electrode

Claims

1. A basic body preparation step of preparing a rectangular parallelepiped electronic component basic body having an internal conductor and having a first main surface and a second main surface opposite to each other in the height direction, a first side surface and a second side surface opposite to each other in the width direction, and a first end surface and a second end surface opposite to each other in the length direction, A component arrangement step of arranging the electronic component body such that the first end face and the second end face each face in the vertical direction, A method for manufacturing a surface-mount electronic component, comprising: an electrode forming step of screen printing an electrode paste onto the first end face and the first main face while tilting the electronic component body toward the second main face side, thereby forming an external electrode on the first end face and the first main face.

2. A method for manufacturing a surface-mount electronic component according to claim 1, wherein in the above-mentioned body placement step, the electronic component body is placed on an adhesive sheet containing a silicone resin.

3. The method for manufacturing a surface-mount electronic component according to claim 1 or 2, wherein, during the screen printing, the maximum inclination angle of the electronic component body with respect to the vertical is 10° or more and 45° or less.

4. A method for manufacturing a surface-mount electronic component according to claim 1 or 2, wherein a mesh screen is used for the screen printing.

5. In the above-mentioned body placement step, the electronic component body is placed in the through-hole of a jig having through-holes in the vertical direction, A method for manufacturing a surface-mount electronic component according to claim 1 or 2, wherein during the screen printing process, the electronic component body is tilted until it comes into contact with the jig.

6. The jig has an inclined surface at its upper end that contacts the electronic component body during screen printing, The method for manufacturing a surface-mount electronic component according to claim 5, wherein the angle of the inclined plane with respect to the vertical direction is 20° or more and 45° or less.

7. The method for manufacturing a surface-mount electronic component according to claim 1 or 2, wherein the electrode paste comprises at least one of a metal paste and a conductive polymer paste.

8. A method for manufacturing a surface-mount electronic component according to claim 1 or 2, wherein in the electrode formation step, the electrode paste is screen printed onto the first end face and the first main face, and then the electrode paste is screen printed onto the first end face and the second main face while tilting the electronic component body toward the first main face, thereby forming the external electrodes on the first end face, the first main face and the second main face.

9. The method for manufacturing a surface-mount electronic component according to claim 1 or 2, wherein the surface-mount electronic component is an electrolytic capacitor.

10. The method for manufacturing a surface-mount electronic component according to claim 1 or 2, wherein the surface-mount electronic component is a multilayer ceramic electronic component.

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