Manufacturing method of electronic components and functional film forming device for electronic components

Abstract

To provide a manufacturing method for an electronic component capable of facilitating the production of an electronic component with excellent reliability, and a functional film formation device for an electronic component suitable for the same.SOLUTION: The method is used for manufacturing an electronic component 2 having an element body 4 provided with a plurality of outer surfaces. To the surface of a first rolling member 20, a glass sheet 24 as a transfer layer is detachably attached. On the surface of the first rolling member 20, a portion of a glass sheet 24 is continuously or intermittently adhered to the outer surface of the element body 4 by rolling it so that the outer surfaces of the element body 4 are in contact with the surface of the first rolling member 20 one after another.SELECTED DRAWING: Figure 6E

Description

[Technical field]

[0001] The present invention relates to a method for manufacturing electronic components such as multilayer ceramic capacitors, and to an apparatus for forming functional films on electronic components. [Background technology]

[0002] For example, in an electronic component such as the multilayer ceramic capacitor shown in Patent Document 1, in order to increase the area of ​​the internal electrode layers while miniaturizing the electronic component, a side gap insulating layer made of a dielectric is formed on the side surface of the element body where the side portion of the internal electrode layer is exposed.

[0003] However, in the conventional manufacturing method, the side gap insulating layer is formed, for example, by a coating method and then fired simultaneously with the element body, which makes it difficult to control the thickness of the side gap insulating layer and the range in which the side gap insulating layer is formed.

[0004] In recent years, electronic components have become smaller, and it is expected that the side gap insulating layer will also be a thin and uniform film. However, there is a problem that it is difficult to form a thin and uniform side gap insulating layer by the coating method. In addition, along with the miniaturization of electronic components, there is also an increasing demand to form functional films such as insulating layers only in necessary areas. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 62-237714 Summary of the Invention [Problem to be solved by the invention]

[0006] The present invention has been made in consideration of the above-described circumstances, and its object is to provide a method for manufacturing electronic components that can easily form a functional film of a specific thickness in a required location even when the electronic component is miniaturized, and a functional film forming apparatus for electronic components that is suitable for this manufacturing method. [Means for solving the problem]

[0007] In order to achieve the above object, a method for manufacturing an electronic component according to the present invention includes: 1. A method for manufacturing an electronic component having a device body with a plurality of exterior surfaces, comprising: The method includes a step (rolling transfer method) of rolling the outer surface of the element body so that the outer surface of the element body is brought into contact with the surface of a rolling member having a transfer layer removably attached to its surface, thereby adhering the transfer layer to the outer surface of the element body continuously or intermittently.

[0008] According to the method for manufacturing electronic components of the present invention, for example, by rolling the side (outer) surface of the element body on a transfer layer having certain characteristics and / or certain thickness so that the sides (outer surfaces) are in continuous contact with each other, an insulating layer can be formed on the desired surface very easily and efficiently.

[0009] Preferably, the rolling member includes a first rolling member having the transfer layer on a surface thereof and being removably attached to the first rolling member; a second rolling member located on the opposite side of the element body from the first rolling member and having a surface in contact with the element body; The second rolling member is moved relative to the first rolling member so that the distance between them can be changed and the second rolling member is displaced substantially parallel to the first rolling member, so that the element body is rolled on the surface of the first rolling member while being in contact with the surfaces of both the first rolling member and the second rolling member. With this configuration, the element body can be rolled (90 degrees at a time) reliably and efficiently.

[0010] In addition, the functional film forming apparatus for electronic components according to the present invention includes: A functional film forming apparatus for electronic components for forming functional films on a plurality of outer surfaces of an element body for an electronic component, comprising: A first rolling member having a transfer layer that becomes the functional film removably attached to a surface thereof; a second rolling member located on the opposite side of the element body from the first rolling member and having a surface in contact with the element body; The device has a drive mechanism that moves the second rolling member relative to the first rolling member so that the distance between them can be changed and the second rolling member is displaced approximately parallel to the first rolling member, in order to sandwich the element body between the first rolling member and the second rolling member and roll it on the surface of the first rolling member.

[0011] The surface of the second rolling member may have a removable adhesive layer. Alternatively, the surface of the transfer layer may have an adhesive layer that can adhere to the outer surface of the element body. This configuration can improve adhesion between the element body and the transfer layer. Also, the transfer layer may have adhesiveness that allows it to adhere to the outer surface of the element body. This configuration eliminates the need to provide an adhesive layer on the transfer layer, simplifying the manufacturing process.

[0012] The element body may be rolled on the surface of the rolling member after being fired, which makes it possible to fire even an insulating layer with a low melting point.

[0013] In addition, the element body may be rolled on the surface of the rolling member before being fired, and the transfer layer may be transferred to the outer surface of the element body, and then the element body may be fired together with the transfer layer. By configuring in this manner, the element body and the insulating layer are fired simultaneously at a high temperature, thereby improving adhesion.

[0014] Preferably, the transfer layer is intermittently and removably attached to the surface of the rolling member, and the transfer layer is intermittently transferred to a plurality of outer surfaces of the element body. By configuring in this way, an insulating layer can be easily formed on a required surface.

[0015] Preferably, the outer surface of the element body has a side surface that is continuous along a circumferential direction and an end surface that intersects with a plurality of the side surfaces, The transfer layer may be formed by rolling the element body on the surface of the rolling member so as to cover the entire outer surface of the element body that is continuous along the circumferential direction. By configuring in this manner, the boundary area of ​​the insulating layer is eliminated and the thickness variation of the insulating layer is also reduced, so that moisture is less likely to enter the internal electrodes, thereby improving reliability.

[0016] The transfer layer attached to the surface of the rolling member may have a notch formed therein. Also, the transfer layer may be transferred to the outer surface of the element body starting from the notch. By configuring in this manner, the transfer layer can be separated from the first transfer member and easily wrapped around the element body.

[0017] The base body to which the transfer layer has been transferred may be pressed against the rolling member from above the transfer layer, thereby separating the transfer layer transferred to the base body from the transfer layer attached to the surface of the rolling member. This configuration makes it easy to cut the transfer layer.

[0018] The transfer layer may be intermittently and removably attached to the surface of the rolling member. The transfer layer may be intermittently transferred to a plurality of outer surfaces of the element body.

[0019] The method of the present invention may further include a step of cleaning the outer surface of the element body by contacting the outer surface of the element body with a cleaning surface formed on the surface of either the rolling member or another rolling member different from the rolling member when the element body is rolled on the surface of the rolling member or the surface of another rolling member different from the rolling member. By configuring in this way, impurities can be removed, thereby improving reliability.

[0020] The transfer layer is preferably a glass sheet or a dielectric sheet. When the transfer layer is a glass sheet, it can be fired at a low temperature. When the transfer layer is a dielectric sheet, it can be fired simultaneously with the body to improve adhesion.

[0021] The transfer layer may cover all of the side surfaces of the element body that are continuous along the circumferential direction. This configuration can block the intrusion path to the interface between the insulating layer made of the transfer layer and the element body over the entire periphery of the side surfaces of the element body, thereby further improving the moisture resistance and reliability of the electronic component.

[0022] The insulating layer formed by heat-treating the transfer layer does not completely cover all the side surfaces of the element body that are continuous along the circumferential direction, but may have a gap in the insulating layer on one of the side surfaces of the element body. That is, on one of the side surfaces of the element body, an edge of the insulating layer may be located along a direction perpendicular to the circumferential direction near the center of the side surface far from the corner of the element body, and a part of the side surface of the element body may be exposed from the gap between the edges.

[0023] In the method of the present invention, the composition of the insulating layer formed by heat-treating the transfer layer can be made substantially uniform along the circumferential direction. Since the composition of the insulating layer is uniform, the moisture resistance is also uniform along the circumferential direction, and the number of starting points that reduce moisture resistance is reduced, improving the reliability of the electronic component. In addition, since the insulating layer can be baked and fired uniformly, the stress acting on the electronic component can be uniformly distributed. Note that, by forming the insulating layer by the rolling transfer method, it is easy to form an insulating layer with a substantially uniform composition along the circumferential direction.

[0024] The thickness of the insulating layer at the corner of the element body can be substantially the same as the thickness of the insulating layer at at least one of the two side surfaces of the element body that sandwich the corner. In particular, by making the thickness of the insulating layer at the corner of the element body the same as that at other parts, the moisture resistance of the electronic component is improved and the reliability is also improved. Since the insulating layer can be formed by a rolling transfer method, the thickness of the insulating layer at the corner of the element body is likely to be substantially uniform compared to other parts.

[0025] The element body may have a laminated structure in which the ceramic layers and internal electrode layers are laminated. A terminal electrode may be formed on an end face of the element body that intersects with the side face, the terminal electrode being connected to an exposed end of the internal electrode layer. Furthermore, preferably, the edge of the terminal electrode covers the end of the insulating layer. This configuration makes it even more difficult for moisture to penetrate into the element body, improving the moisture resistance of the electronic component and improving its reliability. [Brief description of the drawings]

[0026] [Figure 1] FIG. 1 is a schematic cross-sectional view of a multilayer ceramic capacitor according to an embodiment of the present invention. [Figure 2A] FIG. 2A is a cross-sectional view taken along line IIA-IIA shown in FIG. [Figure 2Aa] FIG. 2Aa is a partially enlarged view of the cross-sectional view shown in FIG. 2A. [Figure 2Ab] FIG. 2Ab is a modified example of the partially enlarged view shown in FIG. 2Aa. [Figure 2B] FIG. 2B is a cross-sectional view taken along line IIB-IIB shown in FIG. [Figure 3A] FIG. 3A is a cross-sectional view of a multilayer ceramic capacitor according to another embodiment of the present invention. [Figure 3B] FIG. 3B is a cross-sectional view of a multilayer ceramic capacitor in accordance with still another embodiment of the present invention. [Figure 3C] FIG. 3C is a cross-sectional view of a multilayer ceramic capacitor in accordance with still another embodiment of the present invention. [Figure 4A] 4A is a schematic cross-sectional view parallel to the X-axis and Z-axis showing a lamination step of green sheets in the process of manufacturing the multilayer ceramic capacitor shown in FIG. [Figure 4B] FIG. 4B is a schematic cross-sectional view parallel to the Y-axis and Z-axis showing a lamination process of the green sheets shown in FIG. 4A. [Figure 5A] FIG. 5A is a schematic perspective view of the laminate after the cutting step following the lamination step shown in FIGS. 4A and 4B. [Figure 5B]FIG. 5B is a schematic perspective view of a laminate after a cutting step in the manufacturing process of a multilayer ceramic capacitor in accordance with another embodiment of the present invention. [Figure 6A] FIG. 6A is a schematic perspective view showing a manufacturing process of the multilayer ceramic capacitor of the present invention. [Figure 6B] FIG. 6B is a schematic perspective view showing a continuation of the step shown in FIG. 6A. [Figure 6C] FIG. 6C is a schematic perspective view showing a continuation of the step shown in FIG. 6B. [Figure 6D] FIG. 6D is a schematic perspective view showing a continuation of the step shown in FIG. 6C. [Figure 6E] FIG. 6E is a schematic perspective view showing a continuation of the step shown in FIG. 6D. [Figure 6F] FIG. 6F is a schematic perspective view showing a continuation of the step shown in FIG. 6E. [Figure 6G] FIG. 6G is a schematic perspective view showing a continuation of the step shown in FIG. 6F. [Figure 6H] FIG. 6H is a schematic perspective view of the laminate separated from the sheet after the step shown in FIG. 6G. [Figure 7A] FIG. 7A is a schematic perspective view showing a manufacturing process of a multilayer ceramic capacitor according to a modified example of the present invention. [Figure 7B] FIG. 7B is a schematic perspective view showing a continuation of the step shown in FIG. 7A. [Figure 7C] FIG. 7C is a schematic perspective view showing a continuation of the step shown in FIG. 7B. [Figure 7D] FIG. 7D is a schematic perspective view showing a continuation of the step shown in FIG. 7C. [Figure 7E] FIG. 7E is a schematic perspective view showing a continuation of the step shown in FIG. 7D. [Figure 7F] FIG. 7F is a schematic perspective view showing a continuation of the step shown in FIG. 7E. [Figure 8A] FIG. 8A is a schematic perspective view showing a manufacturing process of a multilayer ceramic capacitor according to another modified example of the present invention. [Figure 8B] FIG. 8B is a schematic perspective view showing a continuation of the step shown in FIG. 8A. [Figure 8C]FIG. 8C is a schematic perspective view showing a continuation of the step shown in FIG. 8B. [Figure 8D] FIG. 8D is a schematic perspective view showing a continuation of the step shown in FIG. 8C. [Figure 8E] FIG. 8E is a schematic perspective view showing a continuation of the step shown in FIG. 8D. [Figure 8F] FIG. 8F is a schematic perspective view showing a continuation of the step shown in FIG. 8E. [Figure 8G] FIG. 8G is a schematic perspective view of the laminate separated from the sheet after the step shown in FIG. 8F. [Figure 9A] FIG. 9A is a schematic perspective view showing a step of cleaning the surface of the laminate. [Figure 9B] FIG. 9B is a schematic perspective view showing a continuation of the step shown in FIG. 9A. [Figure 10A] FIG. 10A is a schematic perspective view illustrating a manufacturing process of a multilayer ceramic capacitor in accordance with still another embodiment of the present invention. [Figure 10B] FIG. 10B is a schematic perspective view showing a continuation of the step shown in FIG. 10A. [Figure 10C] FIG. 10C is a schematic perspective view showing a continuation of the step shown in FIG. 10B. [Figure 10D] FIG. 10D is a schematic perspective view showing a continuation of the step shown in FIG. 10C. [Figure 10E] FIG. 10E is a schematic perspective view showing a continuation of the step shown in FIG. 10D. [Figure 10F] FIG. 10F is a schematic perspective view showing a continuation of the step shown in FIG. 10E. [Figure 10G] FIG. 10G is a schematic perspective view of the laminate separated from the sheet after the step shown in FIG. 10F. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] Hereinafter, the present invention will be described based on the embodiments shown in the drawings.

[0028] First embodiment (Overall structure of multilayer ceramic capacitor) Before describing the method for manufacturing an electronic component according to this embodiment, the overall configuration of a multilayer ceramic capacitor will be described.

[0029] As shown in FIG. 1, the multilayer ceramic capacitor 2 in accordance with this embodiment has a multilayer body (element body) 4 made of a sintered ceramic compact, a first terminal electrode 6, and a second terminal electrode 8.

[0030] As shown in Fig. 1, the laminate 4 has inner dielectric layers (ceramic layers) 10 and internal electrode layers 12 that are substantially parallel to a plane including the X-axis and Y-axis, and the internal electrode layers 12 are alternately laminated between the inner dielectric layers 10 along the direction of the Z-axis. Here, "substantially parallel" means that most of the portions are parallel, but there may be some portions that are not parallel, and the internal electrode layers 12 and the inner dielectric layers 10 may be somewhat uneven or inclined. In the figure, the X-axis, Y-axis, and Z-axis are approximately perpendicular to each other.

[0031] The portion where the inner dielectric layers 10 and the internal electrode layers 12 are alternately stacked is the interior region 13. The laminate 4 also has exterior regions 11 on both end faces in the stacking direction Z (Z-axis). The exterior region 11 is formed by stacking one or more outer dielectric layers. In the following, the "inner dielectric layer 10" and the "outer dielectric layer" may be collectively referred to as the "dielectric layer (ceramic layer)".

[0032] The materials of the dielectric layers constituting the inner dielectric layer 10 and the exterior region 11 may be the same or different and are not particularly limited, and are composed mainly of, for example, a dielectric material with a perovskite structure such as ABO3 or an alkali niobate ceramic. In ABO3, A is, for example, at least one of Ca, Ba, Sr, etc., and B is at least one of Ti, Zr, etc. The molar ratio of A / B is not particularly limited and is 0.980 to 1.020.

[0033] The number of layers of the inner dielectric layer 10 and the outer dielectric layer may be appropriately determined depending on the application, etc. The thickness td of the inner dielectric layer 10 shown in Fig. 2A is, for example, 0.1 µm to 40 µm. The ratio of the thickness td of the inner dielectric layer 10 to the thickness te of the internal electrode layer 12 is not particularly limited, but it is preferable that td / te is 2 to 0.5. In addition, the ratio of the thickness t0 of the exterior region 11 (see Fig. 1) to the height H0 of the element 3 (see Fig. 2A) is not particularly limited, but it is preferable that t0 / H0 is 0.01 to 0.1.

[0034] The shape and size of element 3 may be appropriately determined depending on the purpose and application, but it is preferable that the width W0 in the X-axis direction is 0.1 mm to 3.2 mm, the length L0 in the Y-axis direction is 0.2 mm to 3.2 mm, and the height H0 in the Z-axis direction is 0.1 mm to 3.2 mm. Note that it is also preferable that the multilayer ceramic capacitor 2 including element 3, first terminal electrode 6, and second terminal electrode 8, be within these ranges.

[0035] 1, one of the alternately stacked internal electrode layers 12 has a lead portion 12α electrically connected to the inside of the first terminal electrode 6 formed on one end face 5e in the Y-axis direction of the laminate 4. The other of the alternately stacked internal electrode layers 12 has a lead portion 12β electrically connected to the inside of the second terminal electrode 8 formed on the other end face 5f in the Y-axis direction of the laminate 4.

[0036] The interior region 13 has a capacitance region 14 and lead-out regions 15A and 15B. The capacitance region 14 is a region where the internal electrode layers 12 are stacked along the stacking direction with the inner dielectric layer 10 sandwiched therebetween. The lead-out region 15A is a region located between the lead-out portions 12α of the internal electrode layers 12 that connect to the terminal electrode 6. The lead-out region 15B is a region located between the lead-out portions 12β of the internal electrode layers 12 that connect to the terminal electrode 8.

[0037] The conductive material contained in the internal electrode layer 12 is not particularly limited, and metals such as Ni, Cu, Ag, Pd, Al, Pt, or alloys thereof can be used. As the Ni alloy, an alloy of Ni and one or more elements selected from Mn, Cr, Co, and Al is preferable, and the Ni content in the alloy is preferably 95% by weight or more. Note that Ni or the Ni alloy may contain various trace components such as P at about 0.1% by weight or less. The internal electrode layer 12 may be formed using a commercially available electrode paste, and the thickness of the internal electrode layer 12 may be appropriately determined depending on the application, etc.

[0038] In this embodiment, as shown in Fig. 2A, the four side surfaces 5a to 5d of the laminate 4 as the element body are continuously covered with the insulating layers 16a to 16d that are continuous along the circumferential direction. That is, the insulating layers 16a to 16d are continuously formed along the circumferential direction on the side surfaces 5a, 5c located on both sides along the Z axis of the laminate 4 and the side surfaces 5b, 5d located on both sides along the X axis of the laminate 4 so as to cover the side surfaces 5a to 5d. In this specification, the direction around the Y axis of the laminate, including the side surfaces 5a to 5d, may be referred to as the circumferential direction or the outer periphery direction.

[0039] In this embodiment, the configurations of the insulating layers 16a to 16d are substantially identical, and in the following, for ease of explanation, unless otherwise specified, the explanation will be given of the insulating layers 16a and 16b, and the explanation of the insulating layers 16c and 16d will be omitted.

[0040] As shown in FIG. 2Aa, the insulating layer 16a formed on the side surface 5a located on the upper side along the Z axis of the laminate 4 has a substantially uniform thickness tz in the Z axis direction. Here, the thickness tz refers to the shortest distance from the outer peripheral surface 16a1 of the insulating layer 16a, which is approximately parallel to the XY plane, to the side surface 5a of the laminate 4. Also, the insulating layer 16b formed on the side surface 5b located on one side along the X axis of the laminate 4 has a substantially uniform thickness tx in the X axis direction. Here, the thickness tx refers to the shortest distance from the outer peripheral surface 16b1 of the insulating layer 16b, which is approximately parallel to the YZ plane, to the side surface 5b of the laminate 4. In this embodiment, the thickness tx and the thickness tz are substantially the same.

[0041] In this embodiment, a corner 17 where the side surface 5a and the side surface 5b intersect is preferably formed with an R portion having a predetermined radius of curvature, and the thickness tp of the insulating layer 16p at the corner 17 is substantially the same as at least one of the thickness tx and the thickness tz, and preferably as both. In this specification, the insulating layers 16a to 16d may be used to include the insulating layer 16p at the corner 17.

[0042] Here, when the interface between the laminate 4 and the insulating layers 16a, 16b is clearly visible, the corner 17 refers to a corner where the side surfaces 5a and 5b of the laminate 4 intersect. When the interface between the laminate 4 and the insulating layers 16a, 16b is not clearly visible, the corner 17 refers to a corner where the outer peripheral surfaces 16a1 of the insulating layer 16a intersect with the outer peripheral surface 16b1 of the insulating layer 16b.

[0043] For example, a corner is defined as a region centered on a line P1 on the outer periphery of the insulating layer that is closest to an intersection line P0 between an XY plane formed by an extension of an outer periphery 16a1 of insulating layer 16a and a YZ plane formed by an extension of an outer periphery 16b1 of insulating layer 16b. The thickness tp of the insulating layer at corner 17 is defined as the shortest distance from P1 to laminate 4.

[0044] The phrase "thickness tp of the insulating layer at corner portion 17 is substantially the same as at least one of thickness tx and thickness tz, and preferably substantially the same as both" is determined, for example, as follows.

[0045] The thickness tp of the insulating layer at the corner 17 is measured at 10 or more points on different cross sections in the Y-axis direction, and the average value tpm and the variation σpm are calculated. In addition, the tz of the insulating layer 16a is measured at 10 or more points on different cross sections in the Y-axis direction at the center position of the laminate 4 in the X-axis direction, and the average value tzm and the variation σzm are calculated. Similarly, the tx of the insulating layer 16b is measured at 10 or more points on different cross sections in the Y-axis direction at the center position of the laminate 4 in the Z-axis direction, and the average value txm and the variation σxm are calculated.

[0046] When the difference between the average value tpm of the insulating layer thickness at the corner 17 and the average value tzm of the thickness 16a1 of the insulating layer 16a is 1 / 10 μm or less of tzm, they are determined to be substantially the same. The difference between the average value tpm of the insulating layer thickness at the corner 17 and the average value txm of the thickness 16b1 of the insulating layer 16b can also be determined in the same manner.

[0047] In this embodiment, insulating layer 16a and insulating layer 16b are smoothly, uniformly and continuously connected at corner 17, with substantially no gaps from insulating layer 16a to insulating layer 16b and no interface between insulating layer 16a and insulating layer 16b.

[0048] In this embodiment, the thickness of each of the insulating layers 16a to 16d and the thickness (average and variation) of the insulating layer 16p at each corner 17 can be determined in the same manner as described above, and all of these thicknesses can be made substantially the same.

[0049] The thickness of the insulating layers 16a to 16d and 16p is preferably within a range of 3 μm to 40 μm, more preferably 3 to 30 μm, and particularly preferably 3 to 20 μm, and can be made relatively thin and uniform. This reduces the effect of the thermal expansion coefficient of the insulating layers, and can suppress structural defects due to the difference in thermal expansion coefficient between the laminate 4 and the insulating layers. In this embodiment, the insulating layers 16b and 16d serve as side gap insulating layers, and the exposed end portions of the internal electrode layers 12 in the X-axis direction can be covered with the insulating layers 16b and 16d, providing a sufficient protective function. In this embodiment, the thickness of each of the insulating layers 16a to 16d and 16p also has a small variation.

[0050] By making the thickness of the insulating layer uniform, the number of starting points that reduce moisture resistance is reduced, and the moisture resistance and reliability of the electronic component are improved. Since the insulating layer can be formed by a rolling transfer method, the thickness of the insulating layer tends to be substantially uniform along the circumferential direction.

[0051] In this embodiment, the outer peripheral surface of the insulating layer 16p at the corner 17 does not have to be rounded. For example, as shown in FIG. 2Ab, when the corner 17 of the laminate 4 is chamfered, the outer peripheral surface of the insulating layer 16p becomes flat along the C-plane of the laminate 4. In this case, P1 is located on the outer peripheral surface of the insulating layer 16p, which is a flat surface along the C-plane. In another embodiment of this embodiment, the corner 17 may have substantially no R portion or C-chamfered portion, in which case P0 and P1 become as close as possible.

[0052] 1, it is preferable that the insulating layers 16a, 16c (similarly to the insulating layers 16b, 16d, not shown, omitted below) do not substantially cover the end faces 5e, 5f located at both ends in the Y-axis direction of the laminate 4. That is, it is preferable that the insulating layers 16a, 16c do not cover the connection ends of the lead portions 12α or 12β of the internal electrode layers 12 exposed at the end faces 5e, 5f located at both ends in the Y-axis direction of the laminate 4. This is because the terminal electrodes 6, 8 need to be formed on the outer faces 5e, 5f located at both ends in the Y-axis direction of the laminate 4 and connected to the lead portions 12α or 12β of the internal electrode layers 12.

[0053] In this embodiment, the insulating layers 16a to 16d (including 16p / the same applies below) are made of a material having a melting point lower than that of the dielectric layers 10, 11 of the element body 4, and the main component of the insulating layers 16a to 16d is preferably glass containing 25% or more by weight of Si.

[0054] The insulating layers 16a to 16d are mainly made of glass, which enhances the effect of suppressing peeling of the terminal electrodes 6, 8. This is believed to be because the more Si contained in the glass, which is the main component of the insulating layers, the more the plating resistance of the insulating layers improves, and deterioration due to plating can be suppressed. Furthermore, by making the glass, which is the main component of the insulating layers 16a to 16d, contain 25% by weight or more of Si, a diffusion layer in which Si is diffused can be formed. This strengthens the bond between the insulating layers 16a to 16d and the terminal electrodes 6, 8. Therefore, the main component of the insulating layers 16a to 16d in this embodiment is preferably made of glass containing 25% by weight to 70% by weight of Si.

[0055] The main component of the insulating layer refers to a component contained in the insulating layer at 40 vol % or more, and preferably refers to a component contained in the insulating layer at 60 vol % or more.

[0056] In addition to Si, the insulating layers 16a to 16d of this embodiment may contain Mg, Ca, Sr, Ba, Li, Na, K, Ti, Zr, B, P, Zn, Al, etc.

[0057] Furthermore, by forming the insulating layers from a glass component, the adhesive strength between the insulating layers 16a-16d and the laminate 4 is improved. This is believed to be because a reaction phase is formed at the interface between the glass and the laminate 4, resulting in better adhesion between the glass and the laminate 4 than with other insulating materials.

[0058] Furthermore, glass has higher insulating properties than ceramics, so when the insulating layers 16a-16d are mainly made of glass, the incidence of short circuiting can be reduced even if the distance between the opposing terminal electrodes 6, 8 is shortened, compared to when the insulating layers 16a-16d are mainly made of ceramics.

[0059] The melting point (softening point) of the glass contained in the insulating layers 16a-16d of this embodiment is preferably 600° C. to 950° C. This makes it possible to prevent grain growth of ceramic particles in the dielectric layers when the insulating layers 16a-16d are baked, and to suppress deterioration of properties such as reliability. From the above viewpoints, it is more preferable that the melting point (softening point) of the glass contained in the insulating layers 16a-16d of this embodiment is 600° C. to 850° C.

[0060] The components other than glass contained in the insulating layers 16a to 16d of this embodiment are not particularly limited, and may include, for example, a ceramic filler, BaTiO3, CaTiO3, Al2O3, CaZrO3, MgO, ZrO2, Cr2O3, CoO, etc.

[0061] When the insulating layers 16a to 16d are mainly made of glass, the occurrence rate of short circuits can be reduced even if the terminal electrodes 6, 8 are configured to widely cover the Y-axis direction end portions of the X-axis direction end faces and the Y-axis direction end portions of the Z-axis direction end faces of the laminate 4, compared to when the insulating layers are made of ceramic.

[0062] In this embodiment, a reaction phase may be formed at the interfaces between the insulating layers 16a-16d and the dielectric layers 10, 11, where at least one of the components of the insulating layers 16a-16d has diffused into the dielectric layers 10, 11. By having a reaction phase at the interfaces between the insulating layers 16a-16d and the inner dielectric layer 10, the side surfaces 5a-5d of the laminate 4 are filled with glass, and the void ratio at the interfaces can be minimized. This improves the insulation of the side surfaces of the laminate 4, and improves the voltage resistance.

[0063] Furthermore, by providing a reactive phase at the interfaces between the dielectric layers and the insulating layers 16a-16d, the adhesiveness at the interfaces between the dielectric layers and the insulating layers 16a-16d can be improved, thereby suppressing delamination between the laminate 4 and the insulating layers 16a-16d and increasing the flexural strength.

[0064] The reaction phase can be identified, for example, by performing STEM-EDS analysis of Si element on the interfaces between the dielectric layers and the insulating layers 16a to 16d of the laminate 4 to obtain mapping data of the Si element, and identifying the locations where the Si element is present as the reaction phase.

[0065] In this embodiment, as shown in Fig. 1, both ends of the terminal electrodes 6, 8 in the Z-axis direction are formed so as to cover both ends of the insulating layers 16a, 16c in the Y-axis direction. Also, as shown in Fig. 2B, both ends of the terminal electrodes 6, 8 in the X-axis direction are formed so as to cover both ends of the insulating layers 16b, 16d in the Y-axis direction.

[0066] With this configuration, the terminal electrodes 6, 8 can completely cover the ends of the interfaces between the insulating layers 16a-16d and the laminate 4 at the end faces 5e, 5f of the laminate 4, thereby further improving durability and moisture resistance.

[0067] The thicknesses of the terminal electrodes 6 and 8 may be appropriately determined according to the intended use and the like.

[0068] In this embodiment, when the average weight ratio of Si contained in the glass of the insulating layers 16a to 16d is defined as GSi, and the average weight ratio of Si contained in the glass of the terminal electrodes 6 and 8 is defined as TSi, it is preferable that GSi / TSi satisfies 1.0 < GSi / TSi ≤ 15.0.

[0069] When 1.0 < GSi / TSi ≤ 15.0, a diffusion layer in which Si diffuses can be formed. Compared with the case where GSi / TSi is 1.0 or less, the capacitance can be increased and the strength of the terminal electrode can be improved. Further, when 1.0 < GSi / TSi ≤ 15.0, compared with the case where GSi / TSi is greater than 15.0, the capacitance can be increased and the result of the limit deflection test can be improved. More preferably, GSi / TSi is 2.0 to 8.0.

[0070] (Method for manufacturing a multilayer ceramic capacitor) Next, a method for manufacturing the multilayer ceramic capacitor 2 as an embodiment of the present invention will be specifically described.

[0071] (Manufacturing process of the laminate) First, a manufacturing process of the laminate 4 that becomes the element body will be described. An inner green sheet 10a shown in FIG. 4A that will form the inner dielectric layer 10 shown in FIG. 1 after firing, and an outer green sheet 11a shown in FIG. 4A that will form the exterior region 11 shown in FIG. 1 are prepared.

[0072] In order to form these green sheets 10a and 11a, first, a paste for the inner green sheet and a paste for the outer green sheet are prepared. The paste for the inner green sheet and the paste for the outer green sheet are usually composed of an organic solvent-based paste or an aqueous paste obtained by kneading ceramic powder and an organic vehicle.

[0073] The raw material of the ceramic powder can be appropriately selected from various compounds that become composite oxides or oxides, such as carbonates, nitrates, hydroxides, and organometallic compounds, and can be mixed and used. In this embodiment, the raw material of the ceramic powder is used as a powder having an average particle size of 0.45 μm or less, preferably about 0.05 to 0.3 μm. In order to make the inner green sheet extremely thin, it is desirable to use a powder that is finer than the thickness of the green sheet.

[0074] The organic vehicle is a binder dissolved in an organic solvent. The binder used in the organic vehicle is not particularly limited, and may be appropriately selected from various ordinary binders such as ethyl cellulose, polyvinyl butyral, etc. The organic solvent used is also not particularly limited, and may be appropriately selected from various organic solvents such as alcohol, acetone, toluene, etc.

[0075] Furthermore, the green sheet paste may contain additives selected from various dispersants, plasticizers, dielectrics, minor component compounds, glass frits, insulators, etc. Examples of plasticizers include phthalates such as dioctyl phthalate and benzyl butyl phthalate, adipic acid, phosphate esters, glycols, etc.

[0076] Next, the internal electrode pattern layer 12a shown in FIG. 4A is formed, which will constitute the internal electrode layer 12 shown in FIG. 1 after firing. To this end, a paste for the internal electrode layer is prepared. The paste for the internal electrode layer is prepared by kneading the conductive material made of the various conductive metals and alloys described above with the organic vehicle described above. The metal paste (terminal electrode paste) that will constitute the terminal electrodes 6, 8 shown in FIG. 1 after firing may be prepared in the same manner as the paste for the internal electrode layer described above.

[0077] Using the inner green sheet paste and the internal electrode layer paste prepared above, the inner green sheets 10a and the internal electrode pattern layers 12a are alternately laminated to produce an inner laminate, as shown in Fig. 4A and Fig. 4B. After producing the inner laminate, the outer green sheet paste is used to form the outer green sheet 11a, which is then pressed in the lamination direction to obtain a green laminate.

[0078] As a method for producing the green laminate, in addition to the above, a predetermined number of inner green sheets 10a and internal electrode pattern layers 12a may be alternately laminated directly on the outer green sheet 11a, and pressed in the lamination direction to obtain the green laminate.

[0079] Specifically, first, an inner green sheet 10a is formed on a carrier sheet (e.g., a PET film) as a support by a doctor blade method or the like. After being formed on the carrier sheet, the inner green sheet 10a is dried. Next, an inner electrode pattern layer 12a is formed on the surface of the inner green sheet 10a using an inner electrode layer paste, to obtain the inner green sheet 10a having the inner electrode pattern layer 12a. After stacking the inner green sheets 10a having the inner electrode pattern layer 12a, these may be stacked to obtain a green laminate.

[0080] Next, the green laminate is cut along the C1 and C2 cutting planes in Figures 4A and 4B to obtain green chips 4a. C1 is a cutting plane parallel to the YZ axis plane, and C2 is a cutting plane parallel to the ZX axis plane.

[0081] 4B, the C2 cut surfaces on both sides of the C2 cut surface cutting the internal electrode pattern layer 12a in the nth layer cut the gaps in the internal electrode pattern layer 12a. Also, the C2 cut surface cutting the internal electrode pattern layer 12a in the nth layer cuts the gaps in the internal electrode pattern layer 12a in the (n+1)th layer.

[0082] 5A is obtained by such a cutting method, the n-th internal electrode pattern layer 12a of the green chip 4a is exposed at one end face 5e in the Y-axis direction of the green chip 4a, but not at the other end face 5f. Conversely, the (n+1)-th internal electrode pattern layer 12a of the green chip 4a is not exposed at one bottom face 5e in the Y-axis direction of the green chip 4a, but is exposed at the other bottom face 5f.

[0083] Furthermore, in the C1 cut surface of the green chip 4a shown in Fig. 4A, that is, in the side surfaces 5b and 5d facing the X-axis direction of the green chip 4a shown in Fig. 5A, the internal electrode pattern layer 12a is exposed in all layers. The method for forming the internal electrode pattern layer 12a is not particularly limited, and it may be formed by a printing method, a transfer method, or a thin film forming method such as deposition or sputtering.

[0084] In this embodiment, the binder removal step may be performed, for example, at a holding temperature of 200° C. to 400° C. The firing step may be performed, for example, in a reducing atmosphere, and the annealing step may be performed, for example, in a neutral or weakly oxidizing atmosphere. Other firing and annealing conditions include, for example, a firing holding temperature of 1000° C. to 1300° C. and an annealing holding temperature of 500° C. to 1100° C. The binder removal step, firing step, and annealing step may be performed consecutively or independently.

[0085] In the above-described embodiment, the green laminate shown in Figures 4A and 4B is singulated into green chips 4a, and then the green chips 4a are fired to form the laminate 4. However, the green laminate shown in Figures 4A and 4B may be fired to form a sintered body, and then the sintered body may be cut to form individual laminates 4.

[0086] The corners of the laminate 4 obtained as described above may be chamfered by a barrel or the like to form an R surface as shown in Fig. 2Aa or a C surface as shown in Fig. 2Ab. Furthermore, the end faces 5e and 5f of the laminate 4 may be polished, for example, by barrel polishing or sandblasting, as necessary.

[0087] (Insulating layer formation process) Next, a process for forming an insulating layer (functional film) on the outer periphery of the laminate 4 that becomes the element body will be described. First, a functional film forming apparatus of this embodiment will be described.

[0088] As shown in Fig. 6A, the functional film forming apparatus of this embodiment has a first rolling member 20, a second rolling member 22, and a drive mechanism (not shown) for moving them relatively. The drive mechanism is composed of, for example, a motor, a pressure cylinder, etc. Examples of the motor include a rotary type and a linear type. The drive mechanism drives the second rolling member 22 to be movable along the surface direction relative to the first rolling member 20 in parallel with the first rolling member 20, and such that the mutual distance can be changed in response to the radius of rotation that changes with the rolling of the laminate 4.

[0089] In this embodiment, a winding glass sheet 24 is placed on the upper surface of the first rolling member 20, and an adhesive sheet 26 is provided on the lower surface of the second rolling member 22. As shown in Fig. 6B, a single or multiple laminates 4 are sandwiched between the first rolling member 20 and the second rolling member 22, and in this embodiment, the side surface 5a of the laminate 4 is first attached to the adhesive sheet 26 to form an adhesive layer 26a. Note that, although Fig. 6A shows the laminate 4 attached to the adhesive sheet 26 on the lower surface of the second rolling member 22, the present invention is not limited thereto, and the laminate 4 may be initially only placed on the sheet 24 of the first rolling member 20.

[0090] The first rolling member 20 and the second rolling member 22 may be made of the same material or different materials. The first rolling member 20 and the second rolling member 22 may be, for example, a plate-like or sheet-like member having a certain degree of rigidity, and the material is not particularly limited and may be any of metal, ceramic, plastic, etc.

[0091] The wrapping glass sheet 24 is not particularly limited as long as it is a sheet that becomes the insulating layers 16a to 16d shown in FIG. 2A after heat treatment, and examples thereof include a resin sheet having glass powder dispersed therein, or a semi-hardened glass sheet.

[0092] For example, the glass sheet 24 can be formed by kneading the glass powder raw material constituting the above-mentioned glass component with a binder and a dispersion medium to make a glass slurry, and then forming the glass slurry into a sheet. The glass sheet 24 is placed on the surface of the first rolling member 20 so as to be peelable but not to shift laterally.

[0093] The adhesive layer 26a is disposed on the lower surface of the second rolling member 22 so as to be peelable and not to shift laterally. The adhesive layer 26 may be formed, for example, of a double-sided adhesive sheet, and preferably has a higher adhesive strength to the laminate 4 than to the lower surface of the second rolling member 22. The adhesive layer 26 is formed, for example, of a resin such as synthetic polymers, such as acrylic, polyvinyl butyral, acrylic, polyvinyl alcohol, polyvinyl acetate, and epoxy, and natural polymers, such as rosin and terpene.

[0094] As shown in Fig. 6B, the second rolling member 22 is lowered relative to the first rolling member 20, and the second rolling member 22 presses the laminate 4 toward the first rolling member 20. As a result, a part of the adhesive layer 26 is transferred to the side surface 5a of the laminate 4 to become an adhesive film 26a. Next, as shown in Fig. 6C, while the second rolling member 22 presses the laminate 4 relative to the first rolling member 20 (the reverse may be acceptable / same below), the second rolling member 22 is moved in a direction (the direction of the arrow) in which it shifts parallel to the first rolling member 20 relatively.

[0095] The laminate 4 can be rolled on the first rolling member 20 (or the second rolling member 22) in the circumferential direction of the side surfaces 5a to 5d in accordance with the movement of the second rolling member 22 relative to the first rolling member 20. When rolling the laminate 4, the relative distance of the second rolling member 22 to the first rolling member 20 may change with the change in the rolling rotation radius of the laminate 4. In other words, it is preferable that the laminate 4 is always in contact with both the first rolling member and the second rolling member while rolling.

[0096] 6C, as the laminate 4 rolls, the adhesive layer 26a formed on the side surface 5a of the laminate 4 is cut off and transferred from the lower surface of the second rolling member 22. At the same time, the adhesive sheet 26 is attached to the side surface 5b of the laminate 4, forming an adhesive layer 26b. The winding glass sheet 24 may have a cut 25 formed therein, and the position of the cut 25 preferably coincides with the rolling start position of the side surface 5a of the laminate 4 on the surface of the first rolling member 20.

[0097] When the second rolling member 22 is further moved in the same direction (the direction of the arrow), the laminate 4 rolls, and the adhesive layer 26a formed on the side surface 5a of the laminate 4 adheres to the winding glass sheet 24, forming the outer peripheral film 24a that becomes the insulating layer 16a, as shown in Fig. 6D. In addition, the adhesive sheet 26 adheres to the side surface 5c of the laminate 4, forming an adhesive layer 26c.

[0098] When the second rolling member 22 is further moved in the same direction (the direction of the arrow), the glass sheet 24 is separated from the glass sheet 24 located on the surface of the first rolling member 20 at the cut 25 and transferred to the side surface 5a of the laminate 4 to form the peripheral film 24a, as shown in Fig. 6E. Note that as long as the peripheral film 24a can be transferred to the side surface 5a of the laminate 4, the cut 25 in the glass sheet 24 is not necessarily required.

[0099] When the second rolling member 22 is further moved relatively in the same direction, the adhesive layer 26b formed on the side surface 5b of the laminate 4 is stuck to the winding glass sheet 24, forming a peripheral film 24b serving as an insulating layer, as shown in Fig. 6F. Also, the adhesive sheet 26 is stuck to the side surface 5d of the laminate 4, forming an adhesive layer 26d.

[0100] Similarly, by moving the second rolling member 22 in the same direction to roll the laminate 4, the winding glass sheet 24 adheres to the adhesive layer 26c on the side surface 5c of the laminate 4, forming a peripheral film 24c that serves as an insulating layer, as shown in Fig. 6G. Furthermore, the winding glass sheet 24 adheres to the adhesive layer 26d on the side surface 5d of the laminate 4, forming a peripheral film 24d that serves as an insulating layer.

[0101] Furthermore, by pressing the laminate 4 toward the first rolling member 20 from the upper part of the second rolling member 22 to which the laminate 4 is attached, the outer peripheral film 24d can be separated from the glass sheet 24 located on the first rolling member 20. In this manner, the end of the outer peripheral film 24a and the end of the outer peripheral film 24d are joined to each other, and the laminate 4 around which the outer peripheral films 24a to 24d are wound is obtained, as shown in Fig. 6H.

[0102] Next, the laminate 4 with the peripheral films 24a-24d wound thereon is dried and debindered as necessary, and then baked to obtain the laminate 4 with the insulating layers 16a-16d formed thereon as shown in Fig. 2A. The baking temperature for the peripheral films 24a-24d is preferably 0°C to 150°C, more preferably 10°C to 50°C higher than the melting point (softening point) of the glass contained in the insulating layers 16a-16d.

[0103] Before the baking process, if necessary, the laminate 4 with the outer peripheral films 24a-24d wound thereon may be rolled between the first rolling member 20 and the second rolling member 22 as described above, and one or more layers of similar outer peripheral films 24a-24d may be formed on the outer peripheral films 24a-24d. Also, before the baking process, if necessary, the laminate 4 with the outer peripheral films 24a-24d wound thereon may be deburred by barrel processing or the like.

[0104] After forming the laminate 4 on which the insulating layers 16a to 16d are formed, terminal electrodes 6 and 8 are formed on Y-axis end faces 5e, 5f of the laminate 4, as shown in Fig. 1. In order to form the terminal electrodes 6 and 8, a metal paste is applied to both end faces in the Y-axis direction of the laminate 4 and baked to form a metal paste baked film that becomes the electrode film of the terminal electrodes 6, 8. There are no particular limitations on the method for forming the electrode film of the terminal electrodes 6, 8, and any appropriate method such as application and baking of a metal paste, plating, vapor deposition, sputtering, etc. can be used.

[0105] When applying the metal paste by dipping to the end face in the Y-axis direction of the laminate 4, it is preferable to apply the metal paste so that it spreads to the end faces in the X-axis direction and the Z-axis direction of the laminate 4 as well. The width of the spread in the Y-axis direction is preferably 50 μm to 200 μm. The width of the spread can be controlled by adjusting the viscosity of the metal paste and the dipping conditions. The baking temperature of the metal paste is preferably 0° C. to 50° C. higher than the melting point (softening point) of the glass contained in the terminal electrodes 6, 8.

[0106] A coating layer may be formed by plating, sputtering, or the like on the surfaces of the electrode films of the terminal electrodes 6, 8. The terminal electrodes 6, 8 are formed after the insulating layers 16a to 16d are formed.

[0107] (Summary of the embodiment)

[0108] In this embodiment, the thickness of the adhesive sheet 26 shown in Figures 6A to 6G is 0.3 μm to 4 μm, and is preferably about 1 / 5 to 1 / 20 of the thickness of the glass sheet 24. Since the adhesive sheet 26 having such a thickness is sufficiently thin, as shown in Figure 6G, the end of the peripheral film 24a and the end of the peripheral film 24d made of the glass sheet 24 are joined together without the adhesive sheet 26 getting in the way, and a laminate 4 in which the peripheral films 24a to 24d are wound continuously and seamlessly can be obtained. Therefore, substantially no gap is generated between the formed insulating layer 16a and insulating layer 16d, and the starting point of cracks is suppressed.

[0109] As described above, the method for manufacturing the multilayer ceramic capacitor 2 according to this embodiment includes a step (rolling transfer method) of rolling the side surfaces 5a-5d of the laminate 4 so as to be in continuous contact with each other on a glass sheet (transfer layer) 24 of a constant thickness, thereby continuously adhering the peripheral films 24a-24d to the side surfaces of the laminate 4. Therefore, the multilayer ceramic capacitor 2 according to this embodiment can be manufactured extremely easily.

[0110] The glass sheet 24 is attached to, for example, the side surfaces 5a-5d of the fired laminate 4 and baked to become the insulating layers 16a-16d, a part of which becomes the side gap insulating layer. The insulating layers 16a-16d are made of a material that has a lower melting point than the dielectric layers 10, 11 of the laminate 4, and therefore have a baking temperature that is lower than the firing temperature of the laminate 4. Therefore, the baking temperature for forming the insulating layers 16a-16d has little effect on the laminate 4.

[0111] That is, according to this embodiment, even in a small-sized multilayer ceramic capacitor 2, the insulating layers 16a-16p can be formed continuously on the multiple side surfaces 5a-5d of the element body 4, and the characteristics of the insulating layers 16a-16p can be made substantially uniform along the circumferential direction. Therefore, even in a small-sized multilayer ceramic capacitor 2, the insulating layers 16a-16p do not easily peel off from the corners 17 of the element body 4, and there is little risk of short-circuit defects or the like occurring.

[0112] In addition, in this embodiment, the side gap insulating layer is formed by the rolling transfer method, and therefore, unlike the coating method, no insulating layer is formed in unnecessary portions. Therefore, the insulating layers 16a-16e are not substantially formed on the end faces 5e, 5f of the laminate 4 where the terminal electrodes 6, 8 are formed and connected to the internal electrode layer 12. As a result, even if the laminate 4 as the element body is miniaturized, the connection reliability between the terminal electrodes 6, 8 and the internal electrode layer 12 is improved. Note that "the insulating layers 16a-16e are not substantially formed on the end faces 5e, 5f of the laminate 4" means that the insulating layers are hardly formed compared to the coating method.

[0113] The insulating layers 16a-16d in the multilayer ceramic capacitor 2 of this embodiment are insulating layers that continuously cover the multiple side surfaces 5a-5d along the circumferential direction, and therefore are formed with a substantially constant thickness even in portions other than the side gap insulating layers. In particular, as shown in Fig. 2Aa or Fig. 2Ab, the insulating layers 16p also have a constant thickness tp at the corners 17 of the side surfaces 5a, 5b of the laminate 4. Also, unlike the edges of an insulating layer formed by a coating method, in the multilayer ceramic capacitor 2 of this embodiment, it is not necessary to position the edges of the insulating layers near the corners 17 of the laminate 4.

[0114] In a conventional multilayer ceramic capacitor, the edge of the insulating layer formed by the coating method needs to be positioned near the corner 17 of the laminate 4 so as not to narrow the area of ​​the end faces 5e, 5f of the laminate 4 which are the connection end faces with the terminal electrodes 6, 8. In contrast, in the multilayer ceramic capacitor 2 of this embodiment, the insulating layers 16a to 16d can be formed by the rolling transfer method, so that the insulating layer 16p is formed to a constant thickness even near the corner 17 of the laminate 4 compared to other parts, and unlike the conventional method, the edge of the insulating layer with a thin thickness is not formed near the corner 17. Therefore, it is possible to effectively prevent the intrusion of moisture, and the moisture resistance and reliability of the multilayer ceramic capacitor 2 are improved, and the insulating layer is not easily peeled off from the corners of the element body, so that there is little risk of short circuit defects.

[0115] Moreover, the insulating layers 16a to 16d (including 16p, the same applies below) have a main component made of glass. The insulating layers 16a to 16d, which are mainly made of glass, have a high density and excellent moisture resistance compared to ceramic layers composed of the dielectric layers 10, 11, etc., which place importance on dielectric properties. Therefore, the insulating layers 16a to 16d can effectively protect the exposed ends of the internal electrode layers 12 on the side surfaces of the laminate 4, further improving reliability.

[0116] Furthermore, the insulating layers 16a-16d cover all the side surfaces 5a-5d that are continuous along the circumferential direction of the laminate 4. With this configuration, it is possible to block the intrusion paths to the interfaces between the insulating layers 16a-16d and the laminate 4 all around the side surfaces 5a-5d of the laminate 4, which further improves the moisture resistance and reliability of the multilayer ceramic capacitor 2, and also prevents the insulating layers from peeling off easily from the corners of the element body, reducing the risk of short circuit defects and the like.

[0117] The insulating layers 16a-16d do not need to completely cover all the side surfaces 5a-5d that are continuous along the circumferential direction of the laminate 4, and there may be a gap in the insulating layer 16a on one of the side surfaces 5a-5d, for example, the side surface 5a. That is, on one of the side surfaces 5a-5d of the laminate 4 (for example, 5a), an edge of the insulating layer 16a may be located along a direction perpendicular to the circumferential direction near the center in the X-axis direction of the side surface 5a that is far from the corner of the laminate 4, and a part of the side surface 5a of the laminate 4 may be exposed from the gap between the edges.

[0118] To form such an insulating layer around the side of the laminate 4, the glass sheet 24 can be started to be wound from near the center of the side 4a of the laminate 4 in the X-axis direction, and ended to be wound near the center of the side 4a of the same laminate 4 in the X-axis direction.

[0119] In this embodiment, the composition of the insulating layers 16a-16d can be made substantially uniform along the circumferential direction. Since the insulating layers 16a-16d have a uniform composition, the moisture resistance is also uniform along the circumferential direction, which reduces the number of starting points that reduce the moisture resistance, thereby improving the reliability of the multilayer ceramic capacitor 2. Note that, by forming the insulating layers 16a-16d by the rolling transfer method, it is easy to form the insulating layers 16a-16d with a substantially uniform composition along the circumferential direction.

[0120] In this embodiment, the thickness of the insulating layers 16a-16d can be formed by baking the glass sheet 24 wound in one or more layers, and can be, for example, 3 μm to 40 μm. Since the insulating layers 16a-16d are formed from glass sheets of uniform thickness, the thickness of the insulating layers 16a-16d is substantially uniform along the circumferential direction. By making the thickness of the insulating layers 16a-16d uniform, the starting points that reduce moisture resistance are reduced, improving the moisture resistance of the multilayer ceramic capacitor 2 and improving reliability. Since the insulating layers 16a-16d can be formed by a rolling transfer method, the thickness of the insulating layers 16a-16d is likely to be substantially uniform along the circumferential direction.

[0121] Furthermore, in this embodiment, as shown in Fig. 2Aa or 2ab, the thickness tp of the insulating layer 16b at the corner 17 of the laminate 4 can be made substantially the same as the thickness tz or tx of the insulating layers 16a, 16b at at least one of the two side surfaces 5a, 5b of the laminate 4 that sandwich the corner 17. In particular, by making the thickness tp of the insulating layer 16p at the corner 17 of the element 3 the same as the thickness tz or tx of the other portion, the moisture resistance of the multilayer ceramic capacitor 2 is improved, and the reliability is also improved. Since the insulating layer 16p can be formed by the rolling transfer method, the thickness tp of the insulating layer 16p at the corner 17 of the element 3 is likely to be substantially uniform compared to the thickness tz or tx of the other portion.

[0122] In this embodiment, the insulating layers 16a to 16d completely cover the outer periphery of the laminate 4, so that the ends of the interfaces between the insulating layers 16a to 16d and the laminate 4 can be completely covered from the outside air, thereby further improving durability and moisture resistance.

[0123] 1 and 2B, in this embodiment, terminal electrodes 6, 8 are formed on end faces 5e, 5f of the laminate 4, and the edges of the terminal electrodes 6, 8 cover parts of the insulating layers 16a-16d located on the outer faces 5a-5d of the laminate 4. Therefore, at the end faces 5e, 5f of the laminate 4, the terminal electrodes 6, 8 can cover the ends of the interfaces between the insulating layers 16a-16d and the laminate 4, thereby further improving durability and moisture resistance.

[0124] In this embodiment, a glass sheet is wrapped around the fired laminate 4 and baked to form an insulating layer on the laminate 4. By forming an insulating layer in this manner, it is possible to improve the moisture resistance of the electronic components and to improve durability against external environmental changes such as thermal shock and physical shock.

[0125] The insulating layers 16a to 16d are formed from a single winding glass sheet 24, each of which is continuous, and the interfaces between the insulating layers 16a to 16d and the laminate 4 are not exposed to the outside. This makes it difficult for moisture to penetrate the interfaces, effectively preventing cracks from occurring at the interfaces.

[0126] In this embodiment, in the cross section shown in FIG. 2A, the variation in the arrangement of the ends in the X-axis direction of the internal electrode layers 10 of the laminate 4 can be kept within 5 μm, for example.

[0127] Second embodiment The method for manufacturing a multilayer ceramic capacitor according to this embodiment differs from the first embodiment only in the method for forming an insulating layer on the outer periphery of the laminate 4, and so a description of the common parts will be omitted and the following description will focus mainly on the different parts. The parts that will not be described below are the same as those in the first embodiment.

[0128] The method for manufacturing the multilayer ceramic capacitor according to this embodiment differs from the method for manufacturing the multilayer ceramic capacitor according to the first embodiment in the step of forming insulating layers 16a to 16d on the outer periphery of side surfaces 5a to 5d of the laminate 4, as shown in FIGS. 7A to 7F.

[0129] 7A, a winding glass sheet 24 is laid on the upper surface of the first rolling member 20, and an adhesive sheet 26 is attached to the upper surface of the winding glass sheet 24. In this embodiment, unlike the first embodiment, no adhesive layer is formed on the second rolling member 22, but the second rolling member 22 itself may have adhesiveness.

[0130] The adhesive second rolling member 22 is not particularly limited, and may be, for example, a sheet whose surface itself is an adhesive surface, such as a foam sheet, a rubber sheet such as silicone, an acrylic tape, a UV tape (a tape whose adhesive strength weakens when exposed to UV light), etc. Examples of resins constituting the foam sheet include urethane, acrylic, silicone, polyester, polyurethane, etc.

[0131] 7B, the second rolling member 22 is lowered, and the laminate 4 is pressed against the first rolling member 20 by the second rolling member 22. The side surface 5a of the laminate 4 is attached to the adhesive sheet 26, and an outer peripheral film 24a that becomes an adhesive layer 26a and an insulating layer 16a is formed. The winding glass sheet 24 may have a cut 25 formed therein, and the position of the cut 25 coincides with the edge position of the side surface 5d of the laminate 4.

[0132] As shown in Figure 7C, when the second rolling member 22 presses the laminate 4 against the first rolling member 20 while moving the second rolling member 22 in the direction of the arrow in the same manner as in the first embodiment, the laminate 4 rolls and the outer peripheral film 24a is cut off from the winding glass sheet 24 at the notch 25.

[0133] When the second rolling member 22 is further moved in the same direction as above, the laminate 4 rolls, as shown in FIG. 7D, and the adhesive sheet 26 is attached to the side surface 5b of the laminate together with the sheet 24, forming an adhesive layer 26b and an outer peripheral film 24b that becomes the insulating layer 16b.

[0134] When the second rolling member 22 is further moved in the same direction as above, the laminate 4 rolls, as shown in FIG. 7E, and the adhesive sheet 26 is attached to the side surface 5c of the laminate together with the sheet 24, forming an adhesive layer 26c and an outer peripheral film 24c that becomes the insulating layer 16c.

[0135] By further rolling the laminate 4, as shown in FIG. 7F, the laminate 4 rolls, and the adhesive sheet 26 adheres to the side surface 5d of the laminate, forming an adhesive layer 26d and a peripheral film 24d that becomes an insulating layer 16d.

[0136] Furthermore, as shown in Fig. 7F, by pressing the laminate 4 against the first rolling member 20 from above the second rolling member 22 to which the laminate 4 is attached, the outer peripheral film 24d can be separated from the winding glass sheet 24. In this manner, the end of the outer peripheral film 24a and the outer peripheral film 24d are bonded, and the outer peripheral films 24a to 24d shown in Fig. 6H are wound to obtain the laminate 4. The outer peripheral films 24a to 24d shown in Fig. 6H become the insulating layers 16a to 16d shown in Fig. 2A after baking treatment.

[0137] Third embodiment The method for manufacturing a multilayer ceramic capacitor according to this embodiment differs from the first or second embodiment only in the method for forming an insulating layer on the outer periphery of the laminate 4, and therefore a description of the common parts will be omitted and the following description will focus mainly on the different parts. The parts that are not described below are the same as those described in the above-mentioned embodiments.

[0138] As shown in FIGS. 8A to 8F, the method for manufacturing the multilayer ceramic capacitor according to this embodiment differs from the method for manufacturing the multilayer ceramic capacitor according to the first embodiment in the configuration of the glass sheet in the step of forming an insulating layer on the outer periphery of the laminate 4.

[0139] 8A, an adhesive glass sheet 28 for wrapping is laid on the upper surface of the first rolling member 20. The adhesive glass sheet 28 for wrapping can be manufactured in the same manner as the glass sheet 24 of the first embodiment, and the glass sheet 28 can be made adhesive by adjusting the content or components of, for example, a binder and / or a dispersion medium and other tackifying components.

[0140] As the binder, for example, ethyl cellulose, polyvinyl butyral, etc. can be used, and it is preferable to make the content thereof higher than that of the first embodiment. In addition, as the dispersion medium, for example, terpineol, acetone, etc. can be used, and as other tackifying components, for example, polyvinyl butyral, acrylic, polyvinyl alcohol, polyvinyl acetate, synthetic polymers such as epoxy, natural polymers such as rosin, terpene, plasticizers such as dioctyl phthalic acid, etc. can be used, and it is preferable to make the content thereof higher than that of the first embodiment.

[0141] As shown in Fig. 8B, the second rolling member 22 is lowered, and the laminate 4 is pressed against the first rolling member 20 by the second rolling member 22. The side surface 5a of the laminate 4 is attached to the adhesive glass sheet 28 for winding, and an outer peripheral film 28a that becomes the insulating layer 16a is formed. The adhesive glass sheet 28 for winding may have a cut 29 formed therein.

[0142] As shown in FIG. 8C, when the second rolling member 22 presses the stack 4 against the first rolling member 20 and moves the second rolling member 22 in the direction of the arrow as in the previously described embodiment, the stack 4 rolls and the outer circumferential film 28a adheres to the stack 4 and is pulled away from the surface of the first rolling member 20.

[0143] When the second rolling member 22 is further moved in the same direction as above, the laminate 4 rolls, as shown in Fig. 8D, and the adhesive glass sheet 28 for wrapping is attached to the side surface 5b of the laminate, forming the outer peripheral film 28b that will become the insulating layer 16b. When the second rolling member 22 is further moved in the direction of the arrow, the laminate 4 rolls, as shown in Fig. 8E, and the adhesive glass sheet 28 for wrapping is attached to the side surface 5c of the laminate, forming the outer peripheral film 28c that will become the outer peripheral layer 16c. By further rolling the laminate 4, the laminate 4 rolls, as shown in Fig. 8F, and the adhesive glass sheet 28 for wrapping is attached to the side surface 5d of the laminate, forming the outer peripheral film 28d that will become the outer peripheral layer 16d.

[0144] Furthermore, as shown in Fig. 8F, by pressing the laminate 4 against the first rolling member 20 from above the second rolling member 22 to which the laminate 4 is attached, the outer peripheral film 28d can be separated from the adhesive glass sheet 28 for wrapping. In this way, the end of the outer peripheral film 28a and the outer peripheral film 28d are bonded, and as shown in Fig. 8G, the outer peripheral films 28a to 28d are wrapped around the laminate 4 to obtain the outer peripheral films 28a to 28d shown in Fig. 8G. The outer peripheral films 28a to 28d shown in Fig. 8G become the insulating layers 16a to 16d shown in Fig. 2A after baking treatment.

[0145] In this embodiment, before the outer peripheral films 28a to 28d are wound around the laminate 4 to form the laminate 4, the side surfaces 5a to 5d and / or the end surfaces 5e, 5f of the laminate 4 may be subjected to a cleaning treatment.

[0146] When performing a cleaning process, it is preferable that the surfaces of the first rolling member 20 and the second rolling member 22 have adhesiveness. The first rolling member 20 and the second rolling member 22 having adhesiveness may be made of the same material or different materials.

[0147] These first rolling members 20 and second rolling members 22 are not particularly limited, and may be, for example, a sheet whose surface itself is an adhesive surface, such as a foam sheet, a rubber sheet such as silicone, an acrylic tape, a UV tape (a tape whose adhesive strength weakens when exposed to UV rays), etc. Examples of resins constituting the foam sheet include urethane, acrylic, silicone, polyester, polyurethane, etc.

[0148] First, as shown in Fig. 9A, the second rolling member 22 is lowered and the laminate 4 is pressed against the portion of the first rolling member 20 where the adhesive glass sheet 28 for wrapping is not laid by the second rolling member 22. Next, as shown in Fig. 9B, when the second rolling member 22 is moved in the direction of the arrow in the same manner as in the above-mentioned embodiment, the laminate 4 rolls, and the side surface 5a of the laminate 4 that was attached to the adhesive first rolling member 20 and the side surface 5c of the laminate 4 that was attached to the second rolling member 22 are peeled off from the upper surface of the first rolling member 20 and the lower surface of the second rolling member 22. At that time, dust and the like are transferred from the surfaces of the side surfaces 5a and 5c of the laminate 4 to the contact surfaces of the first rolling member 20 or the second rolling member 22, and the sides 5a and 5c can be cleaned.

[0149] When the second rolling member 22 is further moved in the direction of the arrow, the laminate 4 rolls, and the side surface 5b of the laminate 4 adheres to the first rolling member 20 and the side surface 5d of the laminate 4 adheres to the second rolling member 22. At this time, the position of the side surface 5c of the laminate 4 coincides with the position of the end of the adhesive glass sheet 28 for wrapping.

[0150] When the second rolling member 22 is further moved in the direction of the arrow, the stack 4 rolls, and the side surface 5b of the stack 4 adhering to the first rolling member 20 and the side surface 5d of the stack 4 adhering to the second rolling member 22 are peeled off from the upper surface of the first rolling member 20 and the lower surface of the second rolling member 22. At that time, dust and the like are transferred from the surfaces of the side surfaces 5b and 5d of the stack 4 to the contact surfaces of the first rolling member 20 or the second rolling member 22, and the sides 5b and 5d can be cleaned.

[0151] In other words, in the process of the side surfaces 5a-5d of the laminate 4 peeling off from the upper surface of the first rolling member 20 and the lower surface of the second rolling member 22, cutting waste and debris (for example, setter shavings adhered during firing) that were attached to the side surfaces 5a-5d of the laminate 4 can be adhered to the upper surface of the first rolling member 20 and the lower surface of the second rolling member 22 and removed.

[0152] In Fig. 9B, when the second rolling member 22 is further moved in the same direction as above, the laminate 4 rolls, and the side surface 5c of the laminate 4 adheres to the adhesive glass sheet 28 for wrapping, forming an insulating layer 16c. In this state, the laminate 4 in Fig. 8B is turned upside down, and by moving the second rolling member 22 in this state in the direction of the arrow, a step of forming insulating layers 16a-16d on the outer periphery of the side surfaces 5a-5d of the laminate 4 can be performed immediately after the cleaning process of the laminate 4.

[0153] Moreover, by moving the second rolling member 22 in the Y-axis direction from the state of FIG. 9A, the stack 4 is rotated two times, whereby the end faces 5e and 5f of the stack 4 can also be cleaned.

[0154] In this embodiment, both the first rolling member 20 and the second rolling member 22 have adhesiveness, but the first rolling member 20 does not have to have adhesiveness. In that case, all the side surfaces 5a to 5d of the laminate 4 can be cleaned by moving the position where the laminate 4 is pressed against the first rolling member 20 away from the end of the adhesive glass sheet 28 for wrapping and increasing the number of times of rolling. In addition, by changing the direction of rolling, the end surfaces 5e and 5f of the laminate 4 can also be cleaned. Furthermore, the rolling member for cleaning may be a member different from the rolling member for rolling transfer.

[0155] Fourth embodiment 3A, the method for manufacturing a multilayer ceramic capacitor according to this embodiment differs from the first to third embodiments only in the configuration of the exterior region 11 of the laminate 4, and therefore a description of the common parts will be omitted and the different parts will be mainly described in detail below. The parts not described below are the same as those described in the above-mentioned embodiments.

[0156] In this embodiment, the exterior region 11 is provided with one or more outer dielectric layers made of the same dielectric as the inner dielectric layer 10, and is extremely thinner than the thickness of the exterior region 11 shown in Fig. 2A. In this embodiment, the exterior region 11 shown in Fig. 3A does not need to be formed at all.

[0157] That is, in the element body 4, the exterior region 11 in the stacking direction of the layers (Z-axis direction) forms a side surface, and insulating layers 16a, 16d are formed on the side surfaces 5a, 5d of the exterior region 11. In this embodiment, the thickness of the exterior region 11 is approximately the same as that of the ceramic layer 10 that forms the interior region 13. The melting points of the insulating layers 16a-16p are lower than that of the exterior region 11.

[0158] In this embodiment, the exterior region 11 has a thickness similar to that of the inner dielectric layer 10, or even if there is no exterior region 11, the insulating layers 16a to 16d cover the side surfaces 5a to 5d of the laminate 4, so that it has sufficient protective function and strength, improves the durability and moisture resistance of the multilayer ceramic capacitor 2, and makes it possible to improve reliability for long-term use.

[0159] Fifth embodiment As shown in Fig. 3B, the method for manufacturing a multilayer ceramic capacitor according to this embodiment differs from the first to fourth embodiments only in the configurations of the inner dielectric layer 10 and the ends of the internal electrode layers 12, and a description of the common parts will be omitted and the following description will focus mainly on the different parts. The parts not described below are the same as those described in the above-mentioned embodiments.

[0160] In this embodiment, dielectric gaps 18b, 18d are formed at both ends in the X-axis direction of the inner dielectric layer 10 and the internal electrode layer 12. That is, the outer sides of the dielectric gaps 18b, 18d in the X-axis direction form the side surfaces 5b, 5d of the laminate 4. In this manner, by forming the dielectric gaps 18b, 18d, the ends of the internal electrode layers are covered with the dielectric gaps 18b, 18d, so that it is possible to improve the durability and moisture resistance of the multilayer ceramic capacitor 2 and improve the reliability of long-term use.

[0161] The laminate 4 of this embodiment is obtained by firing the green chip 4a shown in Fig. 5B and going through the process of forming the insulating layers 16a to 16d described above. The green chip 4a shown in Fig. 5B is obtained by changing the pattern shape of the internal electrode pattern layer 12a in the manufacturing process of the laminate described above to a pattern shape in which the internal electrode pattern layer 12a is interrupted at the C1 cross section shown in Fig. 4A.

[0162] In Fig. 3C, an insulating layer is formed on the outer periphery of the laminate 4, in which the thickness of the exterior region 11 (including the dielectric gaps 18b, 18d) in Fig. 3B is approximately the same as that of the dielectric layer 10 forming the interior region. Even with such a structure, it is similar to this embodiment.

[0163] Sixth embodiment 10A to 10G, the method for manufacturing a multilayer ceramic capacitor according to this embodiment differs from the method for manufacturing a multilayer ceramic capacitor according to the above-described embodiment only in the configuration of the adhesive sheet 26 in the step of forming an insulating layer on the outer periphery of the laminate 4, and a description of the common parts will be omitted and the following description will mainly focus on the different parts. The parts not described below are the same as those described in the above-described embodiment.

[0164] In this embodiment, the adhesive sheet 26 is intermittently attached in a predetermined pattern on the winding glass sheet 24 in accordance with the size of the side surface of the element body. That is, the adhesive sheet 26 is attached to positions of the side surface (outer surface) of the laminate 4 corresponding to the portion where an insulating layer is to be formed, and the adhesive sheet 26 is not attached to other portions. In this embodiment, a case where insulating layers 16b, 16d are formed on the side surfaces 5b, 5d shown in FIG. 2A will be described.

[0165] 10A, a winding glass sheet 24 is laid on the upper surface of the first rolling member 20, and an adhesive sheet 26 is attached in a certain pattern to the upper surface of the winding glass sheet 24. In this embodiment, the second rolling member 22 has adhesive properties.

[0166] 10B, the second rolling member 22 is lowered, and the second rolling member 22 presses the laminate 4 against the first rolling member 20. There is no adhesive sheet 26 at a position corresponding to the outer surface 5a of the laminate 4, and therefore no adhesive layer is formed.

[0167] As shown in FIG. 10C, when the second rolling member 22 presses the stack 4 against the first rolling member 20 and moves the second rolling member 22 relatively in the direction of the arrow, the stack 4 starts to roll.

[0168] When the second rolling member 22 is further moved in the direction of the arrow, the laminate 4 rolls, and the adhesive sheet 26 is attached to the outer surface 5b of the laminate, forming an adhesive layer 26b and an outer film 24b that becomes an insulating layer 16b, as shown in Fig. 10D. Note that the winding glass sheet 24 has a cut 25 formed therein, and the position of the cut 25 coincides with the position of the side surface 5a of the laminate 4.

[0169] When the second rolling member 22 is further moved in the direction of the arrow, the laminate 4 rolls, and the outer peripheral film 24b is cut off from the winding dielectric sheet 24 at the notch 25, as shown in Fig. 10E. Also, there is no adhesive sheet 26 at a position corresponding to the outer surface 5c of the laminate 4, and therefore no adhesive layer is formed.

[0170] By further rolling the laminate 4, as shown in FIG. 10F, the laminate 4 rolls, and the adhesive sheet 26 adheres to the outer surface 5d of the laminate, forming an adhesive layer 26d and a peripheral film 24d that becomes an insulating layer 16d.

[0171] 10F, the laminate 4 is pressed against the first rolling member 20 from above the second rolling member 22 to which the laminate 4 is attached, thereby separating the outer peripheral film 24d from the winding glass sheet 24. In this manner, the laminate 4 shown in FIG. 10G is obtained, in which the outer peripheral films 24b, 24d are formed on the outer surfaces 5b, 5d.

[0172] By baking the thus obtained peripheral films 24b, 24d onto the laminate 4, an insulating layer is formed on the outer surfaces 5b, 5d of FIG. 2A, but a laminate 4 without an insulating layer formed on the outer surfaces 5a, 5c can be obtained. In addition, by changing the pattern of the adhesive sheet 26 (the pattern of the cuts 25 can also be changed as necessary), an insulating layer can be formed at any position of the laminate 4. For example, the peripheral films 24b, 24d may be patterned to cover the corners 17 of the laminate 4. Furthermore, the adhesive sheet 26 is not necessarily required, and the glass sheet 24 itself may have adhesiveness and be formed on the first rolling member in a predetermined pattern.

[0173] Seventh embodiment The method for manufacturing a multilayer ceramic capacitor according to this embodiment differs from the first to sixth embodiments only in the method for forming an insulating layer on the outer periphery of the laminate 4, and therefore a description of the common parts will be omitted and the following description will mainly focus on the different parts. The parts that will not be described below are the same as those described in the first to sixth embodiments.

[0174] This embodiment is similar to the previously described embodiment, except that a dielectric sheet is used instead of the glass sheet 24 so that the main component of the insulating layers 16a to 16d is a dielectric material rather than glass.

[0175] The insulating layers 16a-16d (including 16p / hereinafter the same) of this embodiment are made of a dielectric material having substantially the same or different composition as the dielectric layers 10, 11 of the element body 4. Substantially the same composition as the dielectric layers 10, 11 of the element body 4 means, for example, that the main dielectric component of the dielectric layers 10, 11 of the element body 4 is the same as the main dielectric component of the insulating layers 16a-16d. For example, the main dielectric component of the insulating layers 16a-16d may be a dielectric material with a perovskite structure such as ABO3, an alkali niobate ceramic, or the like.

[0176] Preferably, the insulating layers 16a to 16d are made of a composition that contains a greater amount of a component that improves sinterability than the dielectric layers 10 and 11 of the element body 4.

[0177] The composition of the dielectric layers 10, 11 is determined from the viewpoint of improving the characteristics required for electronic components, such as the dielectric constant, while allowing simultaneous firing with the internal electrode layer 12. The composition of the insulating layers 16a-16d is determined so that, while allowing simultaneous firing with the internal electrode layer 12, for example, the dielectric layers 10, 11 do not cause a compositional deviation, and have a composition that is more excellent in sinterability than the dielectric layers 10, 11. From this viewpoint, examples of components that are preferably contained in the insulating layers 16a-16d in greater amounts than the dielectric layers 10, 11 include boron, lithium, silicon (Si), manganese, magnesium, and the like.

[0178] For example, when the insulating layers 16a-16d contain a component such as boron at a content of about 0.1-5.0 mol % higher than the content in the dielectric layers 10, 11, the insulating layers 16a-16d are sintered at a lower temperature than the dielectric layers 10, 11, the sintered density is improved, and the effect of preventing moisture intrusion is enhanced.

[0179] In addition, in this embodiment, since the insulating layers 16a to 16d are mainly made of a dielectric material, the adhesion between the insulating layers and the laminate is improved during sintering, and peeling of the insulating layers is effectively suppressed.

[0180] The dielectric sheet to be used in place of the glass sheet 24 is not particularly limited as long as it is a sheet that becomes the insulating layers 16a to 16d shown in Figure 2A after heat treatment, and examples include a dielectric sheet made of a material having substantially the same main component as the dielectric green sheet for forming the dielectric layers 10 or 11 shown in Figure 1 or a different material, or other semi-cured dielectric sheets.

[0181] For example, the dielectric sheet 24 is preferably made of substantially the same dielectric material as the dielectric green sheet 10a shown in Fig. 4A or 4B as described above, but may be made of different dielectric material. Also, it is preferable that the sub-components of the dielectric material have a high content of a component that improves sinterability, such as boron.

[0182] Moreover, the dielectric sheet 24 preferably contains about 1 to 10% more binder and plasticizer in total than the dielectric green sheet 10a shown in Fig. 4A or 4B. The dielectric sheet 24 is placed on the surface of the first rolling member 20 so as to be peelable and not to shift laterally.

[0183] In this embodiment, it is preferable to simultaneously perform sintering of the laminate 4 and baking of the outer peripheral films 24a to 24d, but it is also possible to perform sintering of the laminate 4 and then baking of the outer peripheral films 24a to 24d.

[0184] The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the present invention.

[0185] For example, in the multilayer ceramic capacitor 2 of the first embodiment shown in Fig. 1, at least one of the outer dielectric layers 11, 11 may be omitted. In the above-mentioned embodiment, the main component of the insulating layers 16a to 16d may be made of a material other than glass or a dielectric. For example, the insulating layers 16a to 16d may be made of ceramic, aluminum, epoxy resin, polyimide resin, etc.

[0186] Furthermore, the method for manufacturing an electronic component according to the present invention is not limited to the method for manufacturing a multilayer ceramic capacitor, but can be applied to the manufacturing methods of other electronic components. Examples of other electronic components include all electronic components in which a functional part is formed on the side surface of the element body (outer surface other than the outer surface on which the terminal electrodes are formed), such as bandpass filters, chip inductors, multilayer three-terminal filters, piezoelectric elements, chip thermistors, chip varistors, chip resistors, and other surface mount (SMD) chip-type electronic components.

[0187] Furthermore, the transfer film formed on the outer surface of the element body by the manufacturing method of the electronic component according to the present invention can be a functional film other than the functional film that becomes an insulating layer when fired. For example, the functional film may be a conductive film that becomes a terminal electrode formed in a predetermined pattern, a film on which characters or a mark for identifying the direction of the chip is written, a color correction film for the appearance of a camera, a permeation prevention film for an internal electrode, a photocatalytic functional film such as TiO2, etc. [Explanation of symbols]

[0188] 2. Multilayer ceramic capacitor 3... Element 4...Laminate (element body) 4a… Green Tip 5a~5d… Side (outer surface) 5e,5f… End surface (outer surface) 6... 1st terminal electrode 6a… Electrode paste film 8... 2nd terminal electrode 10… Inner dielectric layer (ceramic layer) 10a… Inner green sheet 11… Exterior area (ceramic layer) 11a…Outer green sheet 12… Internal electrode layer 12α,12β…Drawer part 12a… Internal electrode pattern layer 13… Interior area 14… Capacity area 15A,15B…Drawer area 16a, 16b, 16c, 16d, 16p... Insulating layers 16a1,16b1,16c1,16d1...outer surface 17…Corner 18b, 18d... Dielectric gap section 20... First rolling member 22... Second rolling member 24… Glass sheet (transfer layer) 24a, 24b, 24c, 24d...Peripheral membrane 25…Cut 26... Adhesive sheet 26a,26b,26c,26d...adhesive film 28...Adhesive glass sheet (transfer layer) 28a, 28b, 28c, 28d...Peripheral membrane 29…Incision

Claims

1. 1. A method for manufacturing an electronic component having a device body with a plurality of exterior surfaces, comprising: The method includes a step of rolling the outer surface of the element body so that the outer surface of the element body is successively brought into contact with the surface of a rolling member having a transfer layer removably attached to the surface, thereby continuously or intermittently attaching the transfer layer to the outer surface of the element body, the transfer layer is intermittently and removably attached to the surface of the rolling member; The transfer layer is intermittently transferred to a plurality of outer surfaces of the element body. A method for manufacturing electronic components.

2. the rolling members include a first rolling member having the transfer layer on a surface thereof and being removably attached thereto, and a second rolling member located on the opposite side of the element body to the first rolling member and having a surface which contacts the element body; 2. A method for manufacturing an electronic component according to claim 1, wherein the second rolling member is moved relative to the first rolling member so that the distance between them can be varied and the second rolling member is displaced approximately parallel to the first rolling member, thereby rolling the element body on the surface of the first rolling member while contacting the surfaces of both the first rolling member and the second rolling member.

3. The method for manufacturing an electronic component according to claim 2 , wherein a surface of the second rolling member has a removable adhesive layer.

4. The method for manufacturing an electronic component according to claim 2 , wherein the surface of the transfer layer has an adhesive layer that is adhesive to the outer surface of the element body.

5. The method for manufacturing an electronic component according to claim 2 , wherein the transfer layer has an adhesive property capable of adhering to the outer surface of the element body.

6. the element body is rolled on a surface of the rolling member before being fired; 6. The method for manufacturing an electronic component according to claim 1, wherein after the transfer layer is transferred to the outer surface of the element body, the element body is fired together with the transfer layer.

7. 6. The method for producing an electronic component according to claim 1, wherein the element body is rolled on the surface of the rolling member after being fired.

8. The transfer layer attached to the surface of the rolling member has a notch formed therein, 8. The method for manufacturing an electronic component according to any one of 1 to 7, wherein the transfer layer is transferred onto the outer surface of the element body starting from the incision.

9. 9. The method for manufacturing an electronic component according to claim 1, wherein the base body to which the transfer layer has been transferred is pressed against the rolling member from above the transfer layer, thereby separating the transfer layer transferred to the base body from the transfer layer attached to the surface of the rolling member.

10. A method for manufacturing an electronic component having a device body with a plurality of outer surfaces, comprising the steps of: The method includes a step of rolling the outer surface of the element body so that the outer surface of the element body is successively brought into contact with the surface of a rolling member having a transfer layer removably attached to the surface, thereby continuously or intermittently attaching the transfer layer to the outer surface of the element body, The method for manufacturing an electronic component further includes a step of cleaning the outer surface of the element body by contacting the outer surface of the element body with a cleaning surface formed on the surface of either the rolling member or another rolling member different from the rolling member when rolling the element body on the surface of the rolling member or the surface of another rolling member different from the rolling member.

11. the transfer layer is intermittently and removably attached to the surface of the rolling member; The method for manufacturing an electronic component according to claim 10 , wherein the transfer layer is intermittently transferred to a plurality of outer surfaces of the element body.

12. The outer surface of the element body has a side surface that is continuous along a circumferential direction and an end surface that intersects with a plurality of the side surfaces, The method for manufacturing an electronic component according to claim 10 , wherein the element body is rolled on the surface of the rolling member so that the transfer layer covers the entire outer surface of the element body that is continuous along the circumferential direction.

13. The method for manufacturing an electronic component according to any one of claims 1 to 12, wherein the transfer layer is either a glass sheet or a dielectric sheet.

14. The method for manufacturing an electronic component according to any one of claims 1 to 13, wherein the composition of the transfer layer is approximately uniform along the surface direction.

15. The method for manufacturing an electronic component according to any one of claims 1 to 14, wherein the transfer layer has a substantially uniform thickness along a surface direction.

16. 16. The method for manufacturing an electronic component according to claim 7, wherein the transfer layer is a glass sheet, and the transfer layer is transferred to the element body after it has been fired.

17. The method for manufacturing an electronic component according to any one of claims 1 to 16, wherein the element body has a laminated structure in which ceramic layers and internal electrode layers are laminated.

18. The method for manufacturing an electronic component according to claim 17 , wherein the element body has an exterior region in a stacking direction, and the transfer layer is formed on an outer surface of the exterior region.

19. The method for manufacturing an electronic component according to claim 18, wherein the exterior region is formed to be thicker than the ceramic layer forming the interior region.

20. 20. The method for manufacturing an electronic component according to claim 18, wherein the thickness of the exterior region is approximately the same as that of the ceramic layer forming the interior region.

21. The method for manufacturing an electronic component according to any one of claims 18 to 20, wherein the exterior region is also formed in a direction perpendicular to the lamination direction of the element body.

22. A functional film forming apparatus for electronic components for forming functional films on a plurality of outer surfaces of an element body for an electronic component, comprising: A first rolling member having a transfer layer that becomes the functional film removably attached to a surface thereof; a second rolling member located on the opposite side of the element body from the first rolling member and having a surface that contacts the element body; a drive mechanism for moving the second rolling member relatively to the first rolling member so that the distance between the second rolling member and the first rolling member is variable and the second rolling member is displaced substantially parallel to the first rolling member in order to sandwich the element body between the first rolling member and the second rolling member and roll the element body on a surface of the first rolling member; The transfer layer is intermittently and removably attached to a surface of the first rolling member so that the transfer layer is intermittently transferred to a plurality of outer surfaces of the element body. Functional film formation equipment for electronic components.

23. A functional film forming apparatus for electronic components for forming functional films on a plurality of outer surfaces of an element body for an electronic component, comprising: A first rolling member having a transfer layer that becomes the functional film removably attached to a surface thereof; a second rolling member located on the opposite side of the element body from the first rolling member and having a surface that contacts the element body; a drive mechanism for moving the second rolling member relatively to the first rolling member so that the distance between the second rolling member and the first rolling member is variable and the second rolling member is displaced substantially parallel to the first rolling member in order to sandwich the element body between the first rolling member and the second rolling member and roll the element body on a surface of the first rolling member; A cleaning surface is formed on the surface of the second rolling member to come into contact with the outer surface of the element body and clean the outer surface of the element body. Functional film formation equipment for electronic components.

Images