JP5239731B2 - Multilayer ceramic electronic component and manufacturing method thereof - Google Patents

Description

  The present invention relates to a multilayer ceramic electronic component and a method for manufacturing the same, and more particularly to a structure of an external terminal electrode provided in the multilayer ceramic electronic component and a method for forming the external terminal electrode.

  In recent years, the market for small portable electronic devices such as mobile phones, notebook computers, digital cameras, and digital audio devices is expanding. In these portable electronic devices, miniaturization is progressing and high performance is also progressing at the same time. A lot of monolithic ceramic electronic components are mounted on portable electronic devices, but miniaturization and high performance are also demanded for monolithic ceramic electronic components. For example, miniaturization and large capacity for monolithic ceramic capacitors. Is required.

  As a means for reducing the size and increasing the capacity of a multilayer ceramic capacitor, it is effective to make the ceramic layer thin. Recently, a ceramic layer having a thickness of about 3 μm has been put into practical use. Currently, the possibility of further thinning is being sought. However, as the ceramic layer is made thinner, a short circuit between the internal electrodes is more likely to occur, which makes it difficult to ensure quality.

  As another means, it is conceivable to increase the effective area of the internal electrode. However, when mass-producing multilayer ceramic capacitors, considering the misalignment and cut misalignment of the ceramic green sheet, the side margin between the internal electrode and the side surface of the ceramic body, or the end surface of the internal electrode and the ceramic body Since it is necessary to secure an end margin to some extent, there is a restriction on expanding the effective area of the internal electrode.

  In order to increase the effective area of the internal electrode while ensuring a predetermined margin, it is necessary to increase the area of the ceramic layer. However, there is a limit to increasing the area of the ceramic layer within the determined dimensional standard, and further, the thickness of the external terminal electrode itself is also hindered.

  Conventionally, the external terminal electrode of a multilayer ceramic capacitor is formed by applying a conductive paste to the end of a ceramic body and baking it. The main method of applying the conductive paste is to immerse and lift the end of the ceramic body in a paste tank containing the conductive paste, but this method is influenced by the viscosity of the conductive paste. The conductive paste tends to adhere thickly to the center of the end face of the ceramic body. For this reason, the area of the ceramic layer has to be reduced by the thickness of the external terminal electrode that is partially thick (for example, more than 30 μm).

  In response to this, a method of directly forming the external terminal electrode by plating has been proposed (for example, see Patent Document 1). According to this method, the plating film is deposited with the exposed portion of the internal electrode on the end face of the ceramic body as a nucleus, and the plating film grows, whereby the exposed portions of the adjacent internal electrodes are connected to each other. Therefore, when this method is applied, it is possible to form a thin and flat external terminal electrode as compared with the conventional method using conductive paste.

However, in the case of the above-described plating method, since the glass adhesive effect in the conventional conductive paste method cannot be obtained, there is a problem that the adhesion of the plating film to the ceramic body, that is, the external terminal electrode is weak.
International Publication No. 2007/049456 Pamphlet

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a multilayer ceramic electronic component having a thin external electrode having excellent adhesion to a ceramic body and a method for manufacturing the same.

  A multilayer ceramic electronic component according to the present invention includes a ceramic body formed by laminating a plurality of ceramic layers, an inner conductor formed inside the ceramic body, and having an exposed portion on the outer surface of the ceramic body. An external terminal electrode formed on the outer surface of the ceramic body and covering the exposed portion of the internal conductor, and in order to solve the above technical problem, the external terminal electrode has the exposed portion of the internal conductor. It includes a Cu plating film to be coated, and is characterized in that Cu oxide exists discontinuously inside the Cu plating film and at least on the interface side with the ceramic body of the Cu plating film.

  The Cu oxide is often present in a ball shape.

Further, Cu oxide may contain a Cu ₂ O and CuO, in this case, the Cu oxide, Cu ₂ O is preferably accounts for at least 90 wt%.

  The inner conductor may include a dummy inner conductor that does not substantially contribute to the development of electrical characteristics.

  An auxiliary conductor may be formed between the external terminal electrode and the ceramic element body in a region other than the exposed portion of the inner conductor on the outer surface of the ceramic element body. In this case, the auxiliary conductor preferably contains glass.

  When the multilayer ceramic electronic component according to the present invention constitutes, for example, a capacitor array or a multi-terminal type low ESL capacitor, the exposed portion of the internal conductor forms at least four rows on the outer surface of the ceramic body. At least four external terminal electrodes are formed so as to correspond to the columns of the exposed portions of the internal conductors.

  When the multilayer ceramic electronic component according to the present invention constitutes, for example, a multilayer ceramic capacitor, a multilayer ceramic inductor, or the like, typically, the ceramic body has first and second main surfaces and first and second opposing each other. The external terminal electrodes include first and second external terminal electrodes respectively formed at different first and second positions on the side surfaces.

  In such an embodiment, when the multilayer ceramic electronic component according to the present invention constitutes a multilayer ceramic capacitor, the internal conductor has an exposed portion at the first position on the side surface and the first external terminal electrode A first internal electrode electrically connected to the first external electrode, and a second internal electrode having an exposed portion at a second position on the side surface and electrically connected to the second external terminal electrode, The first and second internal electrodes are made to face each other with a predetermined ceramic layer interposed therebetween.

  When the multilayer ceramic electronic component according to the present invention constitutes a multilayer ceramic inductor, the internal conductor has a first internal conductor having an exposed portion at the first position on the side surface and a second position on the side surface. A second inner conductor having an exposed portion and disposed at a position different from the first inner conductor in the stacking direction of the ceramic layers is electrically connected to the first inner conductor and the second inner conductor. And a coil conductor extending in a coil shape.

  When the four side surfaces described above are composed of the first and second side surfaces facing each other and the third and fourth side surfaces facing each other, the first external terminal electrode is formed only on the third side surface. The second external terminal electrode may be formed only on the fourth side surface. In this case, the first and second main surfaces and a part of each of the first and second side surfaces are electrically connected to the first external terminal electrode only at the outer peripheral edge of the first external terminal electrode. A second external terminal electrode is formed on the first and second main surfaces and a part of each of the first and second side surfaces, only on the outer peripheral edge of the second external terminal electrode. Preferably, a second edge conductor electrically connected to is formed.

  The present invention is also directed to a method of manufacturing a multilayer ceramic electronic component as described above.

  The method for manufacturing a multilayer ceramic electronic component according to the present invention is formed by laminating a plurality of ceramic layers, has an internal conductor inside, and has an exposed portion where a part of the internal conductor is exposed on the outer surface. A step of preparing a ceramic body, a step of plating the ceramic body, depositing a Cu plating film on the exposed portion of the internal conductor, a heat treatment of the ceramic body, and the Cu plating film and the ceramic body. And a step of generating a Cu liquid phase, an O liquid phase, and a Cu solid phase.

  The heat treatment is preferably performed under conditions of a temperature of 1065 ° C. or higher and an oxygen concentration of 50 ppm or higher.

  According to this invention, after forming a Cu plating film, a Cu liquid phase, an O liquid phase, and a Cu solid phase are generated between the Cu plating film and the ceramic body by performing heat treatment under predetermined conditions. . These mixed phases are easily segregated inside the Cu plating film and at least on the interface side of the Cu plating film with the ceramic body. And when it cools, the said Cu liquid phase and O liquid phase will become solid, and Cu oxide will be produced | generated. The Cu oxide is in a discontinuous state inside the Cu plating film and at least on the interface side of the Cu plating film with the ceramic body. In this state, the Cu oxide acts as an adhesive that firmly bonds the ceramic body and the Cu plating film, and can increase the adhesion of the external terminal electrode including the Cu plating film to the ceramic body, As a result, it is possible to obtain a multilayer ceramic electronic component having an external terminal electrode that has excellent adhesion to the ceramic body.

  Further, since the Cu plating film included in the external terminal electrode is formed by plating, it can be made thinner and flat compared to the case where it is formed using a conductive paste. Therefore, it contributes to the miniaturization of the multilayer ceramic electronic component, and the volume of the ceramic body can be increased within the determined dimensional standard, which contributes to the enhancement of the performance of the multilayer ceramic electronic component. In particular, when applied to a multilayer ceramic capacitor, the capacity can be increased within a predetermined dimensional standard.

When the above-mentioned Cu oxide contains Cu ₂ O and CuO, since Cu ₂ O can realize a strong bonding state by diffusion bonding with the ceramic in particular, Cu ₂ O is 90 wt% in the Cu oxide. If it occupies% or more, the fixing force of the external terminal electrode to the ceramic body can be further increased.

  When the inner conductor includes a dummy inner conductor, the fixing force of the external terminal electrode to the ceramic body can be further improved.

  When the auxiliary conductor is formed in a region other than the exposed portion of the internal electrode on the outer surface of the ceramic body, the external terminal electrode forming region can be easily expanded. As a result, the ceramic body of the external terminal electrode The fixing force with respect to can be further improved.

  The ceramic body has first and second side surfaces facing each other and third and fourth side surfaces facing each other, the first external terminal electrode is formed only on the third side surface, The external terminal electrode is formed only on the fourth side surface, and on the first and second main surfaces and a part of each of the first and second side surfaces, only at the outer peripheral edge of the first external terminal electrode A first edge conductor electrically connected to the first external terminal electrode is formed, and a second external conductor is formed on each of the first and second main surfaces and the first and second side surfaces. When the second edge conductor electrically connected to the second external terminal electrode is formed only at the outer peripheral edge of the terminal electrode, the plating process for forming the external terminal electrode can be completed in a relatively short time. When mounting by soldering due to the presence of edge conductors It is possible to increase the bonding reliability, also, it is possible to reliably inhibit the penetration of moisture into the interior of the ceramic body from the surrounding external terminal electrodes, thereby improving the reliability of the multilayer capacitor.

  In the method for manufacturing a multilayer ceramic electronic component according to the present invention, when the heat treatment is performed at a temperature of 1065 ° C. or higher and an oxygen concentration of 50 ppm or higher, sufficient Cu liquid phase and O liquid phase can be reliably generated. it can.

  1 to 4 are for explaining a first embodiment of the present invention. Here, FIG. 1 is a perspective view showing a multilayer ceramic capacitor 1 as an example of a multilayer ceramic electronic component. 2 is a cross-sectional view taken along line AA in FIG.

  The multilayer ceramic capacitor 1 includes a ceramic body 2. The ceramic body 2 has a rectangular parallelepiped shape having first and second main surfaces 3 and 4 facing each other and four side surfaces 5 to 8 connecting the first and second main surfaces 3 and 4. Yes. In the following description, of the four side surfaces 5 to 8, the side surfaces 5 and 6 extending in the long side direction of the main surfaces 3 and 4 are referred to as first and second side surfaces, respectively, and extend in the short side direction. The side surfaces 7 and 8 will be referred to as first and second end surfaces, respectively.

  First and second external terminal electrodes 9 and 10 are respectively formed on the first and second end faces 7 and 8 of the ceramic body 2.

  Referring mainly to FIG. 2, the ceramic body 2 has a structure in which a plurality of ceramic layers 11 are laminated. A plurality of first and second internal electrodes 12 and 13 are alternately formed in the stacking direction in the ceramic body 2 with a predetermined ceramic layer 11 interposed therebetween. The first internal electrode 12 has an exposed portion 14 on the first end surface 7, and the second internal electrode 13 has an exposed portion 15 on the second end surface 8. The exposed portion 14 of the first internal electrode 12 is covered with the first external terminal electrode 9 and is electrically connected to the first external terminal electrode 9. The exposed portion 15 of the second internal electrode 13 is covered with the second external terminal electrode 10 and is electrically connected to the second external terminal electrode 10.

  FIG. 3 is a plan view showing the internal structure of the ceramic body 2, wherein (1) shows a cross section through which the first internal electrode 12 passes, and (2) shows a cross section through which the second internal electrode 13 passes. Show.

  As shown in FIG. 3, the first and second internal electrodes 12 and 13 both have a rectangular planar shape. The first internal electrode 12 includes a first capacitor portion 16 that faces the second internal electrode 13, and a first lead portion 17 that is drawn from the first capacitor portion 16 to the first end surface 7. ing. Similarly, the second internal electrode 13 has a second capacitor portion 18 and a second lead portion 19.

  FIG. 4 is an enlarged cross-sectional view of a part of FIG. 2, that is, a part where the first external terminal electrode 9 is formed.

  As shown in FIG. 4, the first external terminal electrode 9 includes a Cu plating film 20 formed on the first end surface 7 so as to cover the exposed portion 14 of the first internal electrode 12. . Although not shown, the second external terminal electrode 10 similarly includes a Cu plating film 20. The thickness of the Cu plating film 20 is preferably 1 to 10 μm.

The Cu oxide 21 exists discontinuously inside the Cu plating film 20 and at least on the interface side of the Cu plating film 20 with the ceramic body 2. In FIG. 4, as an example of the discontinuous state, a state in which the Cu oxide 21 exists in a ball shape is shown, but it is not always necessary to exist in such an independent state. May be present. The Cu oxide 21 acts to firmly bond the ceramic body 2 and the external terminal electrodes 9 and 10. Details of this operation will be described later. The Cu oxide 21 may contain Cu ₂ O and CuO. In the Cu oxide 21, the proportion of Cu ₂ O is preferably 90% by weight or more.

The ceramic layer 11 is made of, for example, a dielectric ceramic whose main component is BaTiO ₃ , CaTiO ₃ , SrTiO ₃ , CaZrO ₃ or the like. Note that subcomponents such as a Mn compound, an Fe compound, a Cr compound, a Co compound, and a Ni compound may be added to these main components. Moreover, it is preferable that the thickness of the ceramic layer 11 shall be 1-10 micrometers after baking, for example.

  The size of the ceramic body 2 may be 0402 size, 0603 size, 1005 size, 1608 size, 2012 size, 3216 size, 3225 size (see JEITA standard, etc.), but from the viewpoint of miniaturization and increase in capacity. In other words, it can be said that the present invention is particularly useful for 1005 to 2012 size parts.

As the conductive component contained in the internal electrodes 12 and 13, for example, Ni, Cu, Ag, Pd, an Ag—Pd alloy, Au, or the like can be used. In consideration of reactivity with Cu oxide 21 and Cu such as Cu ₂ O and CuO that can be included in the Cu plating film 20, it is particularly preferable to use Ni. Moreover, it is preferable that the thickness after each baking of the internal electrodes 12 and 13 is 0.5-2.0 micrometers.

  Next, an example of a method for manufacturing the above-described multilayer ceramic capacitor 1 will be described.

  First, a ceramic green sheet to be the ceramic layer 11 and conductive pastes for the internal electrodes 12 and 13 are prepared. These ceramic green sheets and conductive paste contain a binder and a solvent, and a known organic binder and organic solvent can be used as the binder and the solvent, respectively.

  Next, a conductive paste is printed on the ceramic green sheet with a predetermined pattern by, for example, a screen printing method. As a result, a ceramic green sheet on which conductive paste films to be the internal electrodes 12 and 13 are formed is obtained.

  Next, a predetermined number of ceramic green sheets on which conductive paste films are formed as described above are stacked in a predetermined order, and a predetermined number of outer layer ceramic green sheets on which conductive paste films are not formed are stacked. By doing so, a mother laminate in a raw state can be obtained. The raw mother laminate is pressure-bonded in the laminating direction by means such as an isostatic press as required.

  Next, the raw mother laminated body is cut into a predetermined size, whereby the raw ceramic body 2 is cut out.

  Next, the raw ceramic body 2 is fired. The firing temperature depends on the ceramic material contained in the ceramic green sheet and the metal material contained in the conductive paste film, but is preferably selected in the range of 900 to 1300 ° C., for example.

  Next, if necessary, a polishing process such as barrel polishing is performed to expose the exposed portions 14 and 15 of the internal electrodes 12 and 13. At the same time, roundness is formed at the ridges and corners of the ceramic body 2. Further, if necessary, water repellent treatment is performed to prevent the plating solution from entering from the gap between the exposed portions 14 and 15 of the internal electrodes 12 and 13 and the ceramic layer 11.

  Next, the ceramic body 2 is subjected to a plating treatment to deposit a Cu plating film 20 on the exposed portions 14 and 15 of the first and second internal electrodes 12 and 13. As the Cu plating, either electrolytic Cu plating or electroless Cu plating may be employed. However, in the case of electroless Cu plating, pretreatment with a Pd catalyst or the like is required to improve the plating deposition rate. There is a demerit that the process becomes complicated. Therefore, it is preferable to employ electrolytic Cu plating. In order to promote the formation of the Cu plating film 20, strike Cu plating is preferably performed before electrolytic Cu plating or electroless Cu plating. In the plating process, it is preferable to use barrel plating.

  Next, the ceramic body 2 is subjected to heat treatment, and a Cu liquid phase, an O liquid phase, and a Cu solid phase are generated between the Cu plating film 20 and the outer surface of the ceramic body 2. These mixed phases are easily segregated at the interface between the Cu plating film 20 and the outer surface of the ceramic body 2. This is because the liquid phase easily moves toward a minute gap between the Cu plating film 20 and the outer surface of the ceramic body 2 or a minute hole on the surface of the ceramic body 2 during the heat treatment. It is guessed.

  The heat treatment conditions are preferably selected such that the temperature is 1065 ° C. or higher and the oxygen concentration is 50 ppm or higher. When the temperature is less than 1065 ° C. or the oxygen concentration is less than 50 ppm, the Cu liquid phase and the O liquid phase may not be sufficiently generated. The upper limit of the heat treatment temperature is preferably set so as not to exceed the melting point of Cu, and specifically, it is preferably less than 1084 ° C.

Next, the ceramic body 2 is cooled to room temperature. At this time, the Cu liquid phase and the O liquid phase segregated at the interface become solid, and the Cu oxide 21 is formed here. The Cu oxide 21 firmly bonds the ceramic body 2 and the Cu plating film 20. Among them, between the Cu 2 _O and the ceramic by diffusion bonding, is achieved a more robust bonding state. In addition, since the space between the Cu plating film 20 and the ceramic body 2 is sealed with the Cu oxide 21, it is difficult for moisture to enter from the outside, and the reliability of the multilayer ceramic capacitor 1 can be improved.

  FIG. 5 is a view corresponding to FIG. 4 for explaining the second embodiment of the present invention. In FIG. 5, elements corresponding to the elements shown in FIG. 4 are denoted by the same reference numerals, and redundant description is omitted.

  In the second embodiment, a first outer conductive layer 24 and a second outer conductive layer 25 are further formed on the Cu plating film 20.

  The first outer conductive layer 24 is made of a plating film of one kind of metal selected from the group consisting of Cu and Ni or an alloy containing the metal. For example, the first outer conductive layer 24 functions as a solder barrier layer that prevents the Cu plating film 20 from being eroded by solder during solder mounting. In addition, when the 1st outer side conductive layer 24 consists of Cu, since the Cu plating film 20 also consists of Cu, the 1st outer side conductive layer 24 functions as a solder barrier layer by increasing the thickness of Cu film | membrane. become.

  The second outer conductive layer 25 is made of a plating film of one kind of metal selected from the group consisting of Sn, Pb, Au, Ag, Pd, Bi, and Zn or an alloy containing the metal. The material constituting the second outer conductive layer 25 is, for example, solder in solder mounting, conductive adhesive in conductive adhesive mounting, Au in wire bonding mounting, or the like depending on the mounting form. Is selected as appropriate in consideration of compatibility with the adhesive, Au, and the like.

  FIG. 6 is a view corresponding to FIG. 4 for explaining the third embodiment of the present invention. In FIG. 6, elements corresponding to the elements shown in FIG.

  In the third embodiment, the outer conductive layer 28 is further formed on the Cu plating film 20. The outer conductive layer 28 is made of a plating film of one kind of metal selected from the group consisting of Au, Ag and Pd or an alloy containing the metal. The third embodiment is advantageously applied when it is not necessary to deal with solder mounting, for example, when specialized in conductive adhesive mounting or wire bonding mounting. According to the third embodiment, for example, the number of layers of each of the external terminal electrodes 9 and 10 can be reduced as compared with the second embodiment.

  FIG. 7 is a view corresponding to FIG. 4 for explaining a fourth embodiment of the present invention. In FIG. 7, elements corresponding to the elements shown in FIG. 4 are denoted by the same reference numerals, and redundant description is omitted.

  In the fourth embodiment, a first outer conductive layer 31 and a second outer conductive layer 32 are further formed on the Cu plating film 20. The first outer conductive layer 31 is made of a conductive resin containing a thermosetting resin and a metal filler. The second outer conductive layer 32 is made of a plating film of one kind of metal selected from the group consisting of Cu, Ni, Sn, Pb, Au, Ag, Pd, Bi, and Zn or an alloy containing the metal.

  According to the fourth embodiment, when an external stress is applied to the multilayer ceramic capacitor 1, the resin component contained in the first outer conductive layer 31 absorbs the stress, or the first outer conductive layer 31 and the first 2 to cause peeling as a fail-safe function between the two outer conductive layers 32, so that stress is prevented from being directly applied to the ceramic body 2, and as a result, cracks are generated in the ceramic body 2. This can be suppressed.

  FIGS. 8 and 9 are for explaining a fifth embodiment of the present invention. FIG. 8 corresponds to FIG. 2 and FIG. 9 corresponds to FIG. 8 and 9, elements corresponding to those shown in FIGS. 2 and 3 are denoted by the same reference numerals, and redundant description is omitted.

  In the fifth embodiment, dummy inner conductors 35 and 36 that do not substantially contribute to the expression of electrical characteristics are formed inside the ceramic body 2. In this embodiment, the dummy inner conductors 35 and 36 are the inner layer dummy inner conductor 35 formed on the same plane as the first or second inner electrode 12 or 13, and the first and second inner electrodes 12 and 13. The outer layer dummy inner conductor 36 is formed on a surface different from the above.

  The dummy inner conductors 35 and 36 have exposed portions on the end faces 7 and 8 of the ceramic body 2 as in the case of the inner electrodes 12 and 13, and these exposed portions are also the first or second external terminal electrodes 9. Or it coat | covers with 10 and is connected with the Cu plating film 20 (refer FIG. 4). It is preferable to use a metal that reacts with Cu contained in the Cu plating film 20 as the metal contained in the dummy inner conductors 35 and 36. Thereby, the adhering force of the external terminal electrodes 9 and 10 to the ceramic body 2 can be further improved. The dummy inner conductors 35 and 36 preferably include the same metal as that of the inner electrodes 12 and 13. For example, Ni, Cu or the like can be used as a metal included in the dummy inner conductors 35 and 36.

  As shown in FIG. 9, the dummy inner conductors 35 and 36 are preferably formed with the same width as the lead portions 17 and 19 of the inner electrodes 12 and 13. Further, the pattern provided by the two outer layer dummy internal conductors 36 shown in FIG. 9A is the same as the pattern provided by the first inner electrode 12 and the inner layer dummy internal conductor 35 shown in FIG. Further, the pattern provided by the second inner electrode 13 and the inner layer dummy inner conductor 35 shown in FIG. 9 (3) is the same as the pattern provided by the two outer layer dummy inner conductors 36 shown in FIG. 9 (4). Therefore, the manufacturing process can be made common between them.

  FIG. 10 and FIG. 11 are for explaining the sixth embodiment of the present invention. Here, FIG. 10 corresponds to FIG. FIG. 11 is a perspective view showing a state of the ceramic body 2 before the external terminal electrodes 9 and 10 are formed. 10 and FIG. 11, elements corresponding to those shown in FIG. 1 and FIG. 2 are denoted by the same reference numerals, and redundant description is omitted.

  In the sixth embodiment, the area on the outer surface of the ceramic body 2 other than the exposed portions 14 and 15 of the internal electrodes 12 and 13, between the external terminal electrodes 9 and 10 and the ceramic body 2. The auxiliary conductor 39 is formed. More specifically, auxiliary conductors 39 are formed at both ends in the longitudinal direction of the first and second main surfaces 3 and 4 of the ceramic body 2.

  Since the Cu plating film 20 (see FIG. 4) of the external terminal electrodes 9 and 10 is formed by plating, it tends to be difficult to form in regions other than the exposed portions 14 and 15 of the internal electrodes 12 and 13. However, by forming the auxiliary conductor 39, the formation region of the Cu plating film 20 can be easily extended. Thereby, the precipitation area | region of Cu oxide 21 can be enlarged easily, and the adhesion strength with respect to the ceramic body 2 of the Cu plating film 20 can be improved easily.

  The auxiliary conductor 39 preferably contains glass. As the glass, glass containing B or Si such as borosilicate glass can be used. The glass may contain subcomponents such as Ba, Al, and Cu. In addition, about the state of glass, the component can be confirmed by performing the mapping analysis by a wavelength dispersion type | mold microanalyzer (WDX), for example.

  As the auxiliary conductor 39, for example, ceramic green sheets on which a conductive paste film to be the auxiliary conductor 39 is formed are laminated on the uppermost layer and the lowermost layer of the ceramic body 2 in a raw state, It can be formed by co-firing. Alternatively, it may be formed by printing and baking a conductive paste on the first and second main surfaces 3 and 4 of the fired ceramic body 2. In these cases, a conductive paste is used, but since it is applied only to the main surfaces 3 and 4, the thickness of the auxiliary conductor 39 can be 10 μm or less, including the thickness of the external terminal electrodes 9 and 10. However, the thickness can be suppressed to 30 μm or less.

  In addition, it is preferable that the end of the auxiliary conductor 39 is rounded by performing a polishing process such as barrel polishing after the auxiliary conductor 39 is formed.

  12 to 14 are for explaining the seventh embodiment of the present invention. The seventh embodiment is a modification of the sixth embodiment, and FIGS. 12 and 13 correspond to FIGS. 10 and 11, respectively. 12 to 14, elements corresponding to those shown in FIGS. 10 and 11 are denoted by the same reference numerals, and redundant description is omitted.

  In the seventh embodiment, the auxiliary conductor 42 is formed as in the case of the sixth embodiment. More specifically, the auxiliary conductor 42 is formed at each end of each of the first and second main faces 3 and 4 of the ceramic body 2 in the longitudinal direction, and at each of the first and second side faces 5 and 6. Both end portions in the longitudinal direction and the outer peripheral edge portions of the first and second end faces 7 and 8 are formed.

  FIG. 14 is a cross-sectional view showing a preferred method for forming the auxiliary conductor 42 as described above.

  First, as shown in FIG. 14A, the ceramic body 2 is prepared, and a flat plate 45 on which a paste layer 44 made of the conductive paste 43 is formed is prepared.

  Next, as shown in FIG. 14 (2), the first end face 7 of the ceramic body 2 is immersed in the paste layer 44, and then the ceramic body 2 is pulled up as shown in FIG. 14 (3). . At this time, the conductive paste 43 is adhered to the first end face 7.

  Next, as shown in FIG. 14 (4), a flat plate 46 on which no paste layer is formed is prepared.

  Next, as shown in FIG. 14 (5), the first end surface 7 is pressed against the flat plate 46, and the conductive paste 43 attached to the center of the first end surface 7 is the outer peripheral edge of the first end surface 7. Squeezed toward Thereafter, as shown in FIG. 14 (6), when the ceramic body 2 is pulled up, the conductive paste 43 does not adhere or hardly adheres to the central portion of the first end face 7.

  A similar process is performed on the second end face 8 of the ceramic body 2.

  Next, the conductive paste 43 is baked, whereby the auxiliary conductor 42 is formed in the state shown in FIG. In the steps shown in FIGS. 14 (5) and (6), the conductive paste 43 may remain in the center of each of the end faces 7 and 8. After forming the conductor 42, the exposed portions 14 and 15 of the internal electrodes 12 and 13 can be satisfactorily surfaced by performing a polishing process such as barrel polishing.

  The auxiliary conductor 42 in the seventh embodiment has the same function and effect as the auxiliary conductor 39 in the sixth embodiment. However, since the auxiliary conductor 42 in the seventh embodiment is formed up to the first and second main surfaces 3 and 4 of the ceramic body 2, the Cu plating film 20 to be the external terminal electrodes 9 and 10. It becomes easy to form (refer FIG. 4) to the 1st and 2nd side surfaces 5 and 6. FIG. Therefore, since it becomes easy to make the precipitation area | region of Cu oxide 21 go around to the 1st and 2nd side surfaces 5 and 6, the adhesive force of the external terminal electrodes 9 and 10 can be improved easily. Further, since the auxiliary conductor 42 is formed so as to extend to the first and second side surfaces 5 and 6, for example, it is not necessary to particularly form the outer layer dummy internal conductor 36 in the fifth embodiment.

  Also in the case of the seventh embodiment, since it is possible to reduce the thickness by scraping off the surplus portion of the conductive paste 43, the thickness is 30 μm or less even including the external terminal electrodes 9 and 10. It is possible to suppress.

  15 and 16 are for explaining an eighth embodiment of the present invention. FIG. 15 corresponds to FIG. 15, elements corresponding to those shown in FIG. 2 are denoted by the same reference numerals, and redundant description is omitted.

  In the eighth embodiment, the first external terminal electrode 9 is formed only on the first end face 7, and the second external terminal electrode 10 is formed only on the second end face 8. Therefore, a plating film is deposited with the exposed portions 14 and 15 of the internal electrodes 12 and 13 on the end faces 7 and 8 of the ceramic body 2 as nuclei, and this plating film is grown to expose the adjacent internal electrodes 12 and 13. Even with the method of connecting the portions 14 and 15 to each other, the external terminal electrodes 9 and 10 can be formed in a relatively short time.

  In the eighth embodiment, the first and second main surfaces 3 and 4 and the first and second side surfaces 5 and 6 on the end portions on the first end surface 7 side have the first A first edge conductor 49 electrically connected to the first external terminal electrode 9 is formed only at the outer peripheral edge of the external terminal electrode 9. Similarly, on the end portions of the first and second main surfaces 3 and 4 and the first and second side surfaces 5 and 6 on the second end surface 8 side, the second external terminal electrode 10 is outside. A second edge conductor 50 that is electrically connected to the second external terminal electrode 10 only at the periphery is formed.

  The first and second edge conductors 49 and 50 preferably contain glass, as in the case of the auxiliary conductor 39 or 42 described above, and are formed by applying and baking a conductive paste, for example. The baking of the conductive paste may be performed simultaneously with the firing of the ceramic body 2 or after the firing of the ceramic body 2.

  According to the eighth embodiment, the first and second end faces 7 and 8 on the first and second main faces 3 and 4 and the first and second side faces 5 and 6 of the ceramic body 2, respectively. Since the first and second edge conductors 49 and 50 are formed so as to be electrically connected to the outer peripheral edges of the first and second external terminal electrodes 9 and 10 at each end adjacent to each other, when mounting by soldering It is possible to improve the bonding reliability. Further, since the penetration of moisture and the like from the periphery of the external terminal electrodes 9 and 10 into the ceramic body 2 is suppressed as compared with the case where the edge conductors 49 and 50 are not formed, the reliability of the multilayer ceramic capacitor 1 is improved. Can be improved.

  In the eighth embodiment, an outer plating film 51 is further formed on the first external terminal electrode 9 and the first edge conductor 49, and on the second external terminal electrode 10 and the second end. It is preferable that an outer plating film 52 is further formed on the edge conductor 50. By using a metal with good solder wettability in these outer plating films 51 and 52, it is possible to reliably improve the bonding reliability of the multilayer ceramic capacitor 1 when mounted by soldering. Examples of the metal having good solder wettability include Sn and Au.

  The outer plating films 51 and 52 are not limited to a single-layer structure, and, for example, even if they have a two-layer structure, such as forming a Sn plating layer on a Ni plating layer as a base, three more It may be a structure of layers or more.

  FIG. 16 is a cross-sectional view showing a preferred method of forming the edge conductors 49 and 50 described above. FIG. 16 corresponds to FIG. In FIG. 16, elements corresponding to the elements shown in FIG. 14 are denoted by the same reference numerals, and redundant description is omitted.

  First, as shown in FIG. 16A, a ceramic body 2 on which external terminal electrodes 9 and 10 are formed in advance is prepared, and a flat plate 45 on which a paste layer 44 made of a conductive paste 43 is formed is prepared. Is done.

  Next, as shown in FIG. 16 (2), the first end face 7 of the ceramic body 2 is immersed in the paste layer 44 together with the first external terminal electrode 9, and then, as shown in FIG. 16 (3). Next, the ceramic body 2 is pulled up. At this time, the conductive paste 43 is adhered so as to cover the first end surface 7 on which the first external terminal electrode 9 is formed.

  Next, as shown in FIG. 16 (4), a flat plate 46 on which no paste layer is formed is prepared.

  Next, as shown in FIG. 16 (5), the first external terminal electrode 9 on the first end surface 7 is pressed against the flat plate 46, and the conductive paste 43 attached to the first external terminal electrode 9 becomes the first. It squeezes out toward the outer peripheral edge of one external terminal electrode 9. Thereafter, as shown in FIG. 16 (6), when the ceramic body 2 is pulled up, the conductive paste 43 does not adhere or hardly adheres to the portion excluding the outer peripheral edge of the first external terminal electrode 9. It is in a state.

  The same process is also performed on the second end face 8 on which the second external terminal electrode 10 of the ceramic body 2 is formed.

  Next, the conductive paste 43 is baked, thereby forming edge conductors 49 and 50 in the state shown in FIG.

  17 and 18 are for explaining a ninth embodiment of the present invention. Here, FIG. 17 is a perspective view showing a multilayer ceramic capacitor array 101 as an example of the multilayer ceramic electronic component.

  The multilayer ceramic capacitor array 101 includes a ceramic body 102. The ceramic body 102 includes a first side surface 105, a second side surface 106, a second side surface 106, and a first side surface 105 that connect the first and second main surfaces 103 and 104 facing each other and the first and second main surfaces 103 and 104. It has a rectangular parallelepiped shape having three side surfaces 107 and a fourth side surface 108.

  FIG. 18 is a plan view showing the internal structure of the ceramic body 102, and shows different cross sections from FIG. 18 (1) and (2). The ceramic body 102 has a structure in which a plurality of ceramic layers 109 are laminated. Inside the ceramic body 102, a plurality of first and second internal electrodes 110 and 111 are alternately arranged in the laminating direction and alternately in the main surface direction with a predetermined ceramic layer 109 interposed therebetween. Is formed. In this embodiment, two first internal electrodes 110 and two second internal electrodes 111 are alternately arranged in the main surface direction. The first internal electrode 110 has an exposed portion 112 on the first side surface 105, and the second internal electrode 111 has an exposed portion 113 on the second side surface 106.

  As shown in FIG. 17, four first external terminal electrodes 114 and four second external terminal electrodes 115 are formed on the first and second side surfaces 105 and 106 of the ceramic body 102, respectively. ing. The exposed portion 112 of the first internal electrode 110 is covered with the first external terminal electrode 114 and is electrically connected to the first external terminal electrode 114. The exposed portion 113 of the second internal electrode 111 is covered with the second external terminal electrode 115 and is electrically connected to the second external terminal electrode 115.

  The first and second external terminal electrodes 114 and 115 of the multilayer ceramic capacitor array 101 are not shown, but the external terminal electrodes 9 described with reference to FIG. 4, FIG. 5, FIG. 6 or FIG. Structures and forming methods are applied.

  In the multi-terminal type multilayer ceramic electronic component such as the capacitor array 101 according to the ninth embodiment, it is necessary to prevent a solder bridge by securing a certain distance between adjacent external terminal electrodes. In the case of the application method, since it is difficult to apply the conductive paste with high accuracy, it is necessary to secure a slightly larger distance between the exposed internal electrodes, and as a result, miniaturization is hindered. On the other hand, according to the present invention, since direct plating is used to form the external terminal electrodes, the distance between the exposed internal electrodes can be minimized, and the multilayer ceramic electronic component can be reduced in size. Can be further promoted.

  In the ninth embodiment, the eight terminals, that is, the exposed portions 112 and 113 of the internal electrodes 110 and 111 form a total of eight rows, but it is sufficient that at least four rows are formed. It is sufficient that at least four electrodes are formed so as to correspond to each column.

  19 to 21 are for explaining a tenth embodiment of the present invention. Here, FIGS. 19 and 20 correspond to FIGS. 17 and 18, respectively. FIG. 21 is a diagram showing the first and second main surfaces 103 and 104 of the ceramic body 102 before the external terminal electrodes 114 and 115 are formed. 19 to 21, elements corresponding to those shown in FIGS. 17 and 18 are denoted by the same reference numerals, and redundant description is omitted.

  In the tenth embodiment, as shown in FIG. 20, the inner-layer dummy internal conductor 116 formed on the same plane as the first or second internal electrode 110 or 111, and a surface different from both of the internal electrodes 110 and 111 And an auxiliary conductor 118 formed on the first and second main surfaces 103 and 104 of the ceramic body 102, as shown in FIG. It is a feature.

  The dummy inner conductors 116 and 117 have the same effects as the dummy inner conductors 35 and 36 in the fifth embodiment, and the auxiliary conductor 118 has the same effects as the auxiliary conductor 39 in the sixth embodiment. Therefore, according to the tenth embodiment, it is possible to further improve the fixing force of the first and second external terminal electrodes 114 and 115 to the ceramic body 102 as compared with the ninth embodiment, and The formation region of the first and second external terminal electrodes 114 and 115 can be easily extended to the main surfaces 103 and 104.

  In the tenth embodiment, the dummy inner conductors 116 and 117 can be omitted, or the auxiliary conductor 118 can be omitted.

  22 and 23 are for explaining an eleventh embodiment of the present invention. Here, FIG. 22 is a perspective view showing a multi-terminal type low ESL multilayer ceramic capacitor 151 as an example of the multilayer ceramic electronic component.

  The low ESL multilayer ceramic capacitor 151 includes a ceramic body 152. The ceramic body 152 is a rectangular parallelepiped having first and second main surfaces 153 and 154 facing each other and first to fourth side surfaces 155 to 158 connecting the first and second main surfaces 153 and 154. It has a shape.

  FIG. 23 is a plan view showing the internal shape of the ceramic body 152, and shows different cross sections from FIG. 23 (1) and FIG. 23 (2).

  The ceramic body 152 has a structure in which a plurality of ceramic layers 159 are laminated. In the ceramic body 152, a plurality of first and second internal electrodes 160 and 161 are alternately formed in the stacking direction with a predetermined ceramic layer 159 interposed therebetween.

  The first internal electrode 160 includes a first capacitor 162 that faces the second internal electrode 161 and a plurality of first capacitors that are drawn from the first capacitor 162 to the first or second side surface 155 or 156. And an exposed portion 164 exposed to the first or second side surface 155 or 156 is formed at the end of the first drawn portion 163.

  The second internal electrode 161 includes a plurality of second capacitors 165 facing the first internal electrode 160 and a plurality of second capacitors 165 or 156 drawn from the second capacitor 165 to the first or second side surface 155 or 156. An exposed portion 167 that is exposed to the first or second side surface 155 or 156 is formed at an end portion of the second drawer portion 166.

  A plurality of first and second external terminal electrodes 168 and 169 are alternately arranged on the first and second side surfaces 155 and 156 of the ceramic body 152. The exposed portion 164 of the first internal electrode 160 is covered with the first external terminal electrode 168 and is electrically connected to the first external terminal electrode 168. The exposed portion 167 of the second internal electrode 161 is covered with the second external terminal electrode 169 and is electrically connected to the second external terminal electrode 169.

  Regarding the first and second external terminal electrodes 168 and 169 in the eleventh embodiment, the structure and method of forming the external terminal electrode 9 described with reference to FIG. 4, FIG. 5, FIG. 6 or FIG. Applies.

  FIGS. 24 to 26 are for explaining a twelfth embodiment of the present invention. Here, FIG. 24 corresponds to FIG. 22, and FIG. 25 corresponds to FIG. FIG. 26 is a diagram showing the first and second main surfaces 153 and 154 of the ceramic body 152. 24 to 26, elements corresponding to those shown in FIGS. 22 and 23 are denoted by the same reference numerals, and redundant description is omitted.

  The relationship of the twelfth embodiment with respect to the eleventh embodiment is the same as the relationship of the tenth embodiment with respect to the ninth embodiment. That is, in the twelfth embodiment, as shown in FIG. 25, both the inner layer dummy inner conductor 170 formed on the same plane as the first or second inner electrode 160 or 161, and the inner electrodes 160 and 161, 26, and an auxiliary conductor 172 formed on the first and second main surfaces 153 and 154 of the ceramic body 152, as shown in FIG. It is characterized by that.

  The dummy inner conductors 170 and 171 have the same effects as the dummy inner conductors 35 and 36 in the fifth embodiment, and the auxiliary conductor 172 has the same effects as the auxiliary conductor 39 in the sixth embodiment. Therefore, according to the twelfth embodiment, the fixing force of the first and second external terminal electrodes 168 and 169 to the ceramic body 152 can be further improved as compared to the eleventh embodiment, The formation region of the first and second external terminal electrodes 168 and 169 can be easily extended to the first and second main surfaces 153 and 154.

  In the twelfth embodiment, the dummy inner conductors 170 and 171 may be omitted, or the auxiliary conductor 172 may be omitted.

  27 and 28 are for explaining a thirteenth embodiment of the present invention. Here, FIG. 27 is a perspective view showing a multilayer ceramic inductor 201 as an example of the multilayer ceramic electronic component.

  The multilayer ceramic inductor 201 includes a ceramic body 202. The ceramic body 202 has a rectangular parallelepiped shape having first and second main surfaces 203 and 204 facing each other and four side surfaces 205 to 208 connecting the first and second main surfaces 203 and 204. Yes. In the following description, of the four side surfaces 205 to 208, the side surfaces 205 and 206 extending in the long side direction of the main surfaces 203 and 204 are called first and second side surfaces, respectively, and extend in the short side direction. Side surfaces 207 and 208 will be referred to as first and second end surfaces, respectively.

  On the first and second end faces 207 and 208 of the ceramic body 202, first and second external terminal electrodes 209 and 210 are formed, respectively.

  FIG. 28 is an exploded perspective view showing the ceramic body 202 provided in the multilayer ceramic inductor 201.

  The ceramic body 202 has a structure in which a plurality of ceramic layers 211 are stacked. Inside the ceramic body 202, a first inner conductor 213 having an exposed portion 212 on the first end face 207, an exposed portion 214 on the second end face 208, and a first in the stacking direction of the ceramic layers 211. A second inner conductor 215 arranged at a position different from the inner conductor 213 is formed. The exposed portion 212 of the first internal conductor 213 is covered with the first external terminal electrode 209 and is electrically connected to the first external terminal electrode 209. The exposed portion 214 of the second inner conductor 215 is covered with the second external terminal electrode 210 and is electrically connected to the second external terminal electrode 210.

  In addition, a coil conductor 216 extending in a coil shape is formed inside the ceramic body 202 so as to electrically connect the first inner conductor 213 and the second inner conductor 215. The coil conductor 216 includes a plurality of line conductors 217 extending on the predetermined ceramic layer 211 and a plurality of via conductors 218 penetrating the predetermined ceramic layer 211 in the thickness direction. Extended.

  The multilayer ceramic inductor 201 includes a number of dummy inner conductors 219 that do not substantially contribute to the expression of electrical characteristics. The dummy inner conductor 219 has an exposed portion at a position adjacent to the exposed portion 212 or 214 of the first or second inner conductor 213 or 215, and the first and second external terminal electrodes 209 and 210, This acts to further improve the fixing force to the ceramic body 202.

  Although the present invention has been described with reference to the illustrated embodiment, the present invention can be applied to other multilayer ceramic electronic components such as multilayer piezoelectric electronic components and multilayer thermistors.

  Next, experimental examples carried out to confirm the effects of the present invention will be described. In this experimental example, a multilayer ceramic capacitor was produced and evaluated based on the first embodiment.

  First, a ceramic body for a multilayer ceramic capacitor having specifications as shown in Table 1 below was prepared.

  Next, in order to form external terminal electrodes on the ceramic body, a Cu strike is applied by applying a horizontal rotating barrel under the plating conditions shown in Table 3 while using a plating bath as shown in Table 2 below. Plating and Cu thick plating were performed to form a Cu plating film having a thickness of about 10 μm.

  Next, the ceramic body was subjected to heat treatment under the conditions shown in Table 4 below.

  Thereafter, Ni plating and Sn plating were sequentially performed by applying a horizontal rotating barrel under the plating conditions as shown in Table 3 while using a plating bath as shown in Table 2 above. A Ni plating film having a thickness of about 4 μm was formed thereon, and a Sn plating film having a thickness of about 4 μm was formed thereon, and samples according to Samples 1 to 9 were obtained.

  Next, for each sample thus obtained, first, the fixing force of the external terminal electrode was evaluated as follows. Evaluation of the fixing force of the external terminal electrode was performed so as to cause shear fracture in the sample. That is, when a multilayer ceramic capacitor according to each sample is mounted on a substrate by soldering, and a load is applied in a direction parallel to both external terminal electrodes at a load speed of 0.5 mm / second until breakage occurs. The failure mode was observed. Table 5 below shows where the breakage occurred for each sample. Table 5 also shows the number of samples in which breakdown occurred between the Cu plating film and the ceramic body, that is, the number of samples in which electrode peeling occurred in each of the 10 samples as “defective rate”.

  Furthermore, a moisture resistance reliability test was performed. After applying a voltage of 3.2 V to each sample for 72 hours under an environment of 125 ° C. and 95% RH, the sample having an insulation resistance of 1 MΩ or less was determined to be defective, and the number of defective samples in 20 samples Is shown as “Moisture Reliability Failure Rate” in Table 5.

  As shown in Table 5, in samples 1 to 8 and 11, fracture occurred between the Cu plating film and the ceramic body, and the moisture resistance reliability was inferior. In Nos. 12 and 13, destruction occurred inside the ceramic body, and the moisture resistance reliability was excellent. Therefore, as in Samples 9, 10, 12 and 13, heat treatment is performed at a temperature of 1065 ° C. or higher in an oxygen atmosphere of 50 ppm or higher, thereby providing sufficient strength and moisture resistance to the ceramic body. It can be seen that the terminal electrode can be fixed.

1 is a perspective view showing an appearance of a multilayer ceramic capacitor 1 according to a first embodiment of the present invention. It is sectional drawing which follows the line AA of FIG. FIG. 2 is a plan view showing an internal structure of a ceramic body 2 provided in the multilayer ceramic capacitor 1 shown in FIG. 1. It is sectional drawing which expands and shows a part of FIG. It is a figure corresponding to FIG. 4 for demonstrating the 2nd Embodiment of this invention. It is a figure corresponding to FIG. 4 for demonstrating the 3rd Embodiment of this invention. It is a figure corresponding to FIG. 4 for demonstrating 4th Embodiment of this invention. It is a figure corresponding to FIG. 2 for demonstrating the 5th Embodiment of this invention. It is a figure corresponding to FIG. 3 for demonstrating the 5th Embodiment of this invention. It is a figure corresponding to FIG. 2 for demonstrating the 6th Embodiment of this invention. FIG. 9 is a perspective view illustrating a state of a ceramic body 2 before forming external terminal electrodes 9 and 10 for explaining a sixth embodiment of the present invention. It is a figure corresponding to FIG. 10 for demonstrating the 7th Embodiment of this invention. It is a figure corresponding to FIG. 11 for demonstrating the 7th Embodiment of this invention. FIG. 14 is a cross-sectional view illustrating a preferred method for forming the auxiliary conductor shown in FIG. It is a figure corresponding to FIG. 2 for demonstrating the 8th Embodiment of this invention. FIG. 16 is a cross-sectional view illustrating a preferred method for forming edge conductors 49 and 50 shown in FIG. 15 for explaining an eighth embodiment of the present invention. It is a perspective view which shows the external appearance of the multilayer ceramic capacitor array 101 by 9th Embodiment of this invention. FIG. 18 is a plan view showing an internal structure of a ceramic body 102 provided in the multilayer ceramic capacitor array 101 shown in FIG. 17. It is a figure corresponding to FIG. 17 for demonstrating the 10th Embodiment of this invention. It is a figure corresponding to FIG. 18 for demonstrating the 10th Embodiment of this invention. It is for demonstrating 10th Embodiment of this invention, and is a figure which shows the 1st and 2nd main surfaces 103 and 104 of the ceramic element | base_body 102 before forming the external terminal electrodes 114 and 115, respectively. It is a perspective view which shows the external appearance of the multi-terminal type low ESL multilayer ceramic capacitor 151 by 11th Embodiment of this invention. FIG. 23 is a plan view showing an internal structure of a ceramic body 152 provided in the multilayer ceramic capacitor 151 shown in FIG. 22. It is a figure corresponding to FIG. 22 for demonstrating 12th Embodiment of this invention. It is a figure corresponding to FIG. 23 for demonstrating 12th Embodiment of this invention. It is a figure for demonstrating 12th Embodiment of this invention, and is a figure which shows the 1st and 2nd main surface 153 and 154 of the ceramic body 152 before forming the external terminal electrodes 168 and 169, respectively. It is a perspective view which shows the external appearance of the multilayer ceramic inductor 201 by 13th Embodiment of this invention. FIG. 28 is an exploded perspective view showing a ceramic body 202 provided in the multilayer ceramic inductor 201 shown in FIG. 27.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Multilayer ceramic capacitor 2,102,152,202 Ceramic body 3,4,103,104,153,154,203,204 Main surface 5-8,105-108,155-158,205-208 Side surface 9,10 , 114, 115, 168, 169, 209, 210 External terminal electrode 11, 109, 159, 211 Ceramic layer 12, 13, 110, 111, 160, 161 Internal electrode (internal conductor)
14, 15, 112, 113, 164, 167, 212, 214 Exposed portion 20 Cu plating film 21 Cu oxide 35, 36, 116, 117, 170, 171, 219 Dummy inner conductor 39, 42, 118, 172 Auxiliary conductor 49, 50 Edge conductor 51, 52 Plating film 101 Multilayer ceramic capacitor array 151 Multi-terminal type low ESL multilayer ceramic capacitor 201 Multilayer ceramic inductor 213, 215 Internal conductor 216 Coil conductor

Claims (14)

A ceramic body formed by laminating a plurality of ceramic layers;
An inner conductor formed inside the ceramic body and having an exposed portion on an outer surface of the ceramic body;
An external terminal electrode formed on the outer surface of the ceramic body and covering the exposed portion of the internal conductor;
The external terminal electrode includes a Cu plating film that covers the exposed portion of the internal conductor, and is discontinuous inside the Cu plating film and at least on the interface side of the Cu plating film with the ceramic body. Cu oxide is present in the shape,
Multilayer ceramic electronic components.   The multilayer ceramic electronic component according to claim 1, wherein the Cu oxide is present in a ball shape. The multilayer ceramic electronic component according to claim 1, wherein the Cu oxide includes Cu ₂ O and CuO. The multilayer ceramic electronic component according to claim 3, wherein Cu ₂ O accounts for 90 wt% or more in the Cu oxide.   The multilayer ceramic electronic component according to claim 1, wherein the inner conductor includes a dummy inner conductor that does not substantially contribute to the development of electrical characteristics.   The auxiliary conductor is formed in an area on the outer surface of the ceramic body other than the exposed portion of the internal conductor, and between the external terminal electrode and the ceramic body. The multilayer ceramic electronic component according to any one of 5.   The multilayer ceramic electronic component according to claim 6, wherein the auxiliary conductor contains glass.   The exposed portion of the inner conductor is formed to form at least four rows on the outer surface of the ceramic body, and the external terminal electrode is at least corresponding to the row of the exposed portion of the inner conductor. The multilayer ceramic electronic component according to claim 1, wherein four are formed.   The ceramic body has first and second main surfaces facing each other and four side surfaces connecting the first and second main surfaces, and the external terminal electrodes are different from each other on the side surfaces. The multilayer ceramic electronic component according to any one of claims 1 to 8, further comprising first and second external terminal electrodes formed at first and second positions, respectively.   The inner conductor has an exposed portion at the first position on the side surface and is electrically connected to the first external terminal electrode, and the second inner electrode on the side surface. A second internal electrode having an exposed portion at a position and electrically connected to the second external terminal electrode, wherein the first and second internal electrodes are interposed via the predetermined ceramic layer. The multilayer ceramic electronic component according to claim 9, which faces each other.   The internal conductor has an exposed portion at the first position on the side surface and an exposed portion at the second position on the side surface, and in the stacking direction of the ceramic layers, A second inner conductor disposed at a position different from the first inner conductor, and a coil conductor extending in a coil shape so as to electrically connect the first inner conductor and the second inner conductor. The multilayer ceramic electronic component according to claim 9, further comprising:   The four side surfaces are composed of first and second side surfaces facing each other and third and fourth side surfaces facing each other, and the first external terminal electrode is formed only on the third side surface, The second external terminal electrode is formed only on the fourth side surface, formed on each of the first and second main surfaces and the first and second side surfaces, and the first side surface. A first edge conductor electrically connected to the first external terminal electrode only at an outer periphery of the external terminal electrode, the first and second main surfaces, and the first and second side surfaces. 12. A second edge conductor formed on each part and electrically connected to the second external terminal electrode only at the outer periphery of the second external terminal electrode. The multilayer ceramic electronic component according to any one of the above. A step of preparing a ceramic body having a plurality of ceramic layers laminated, having an internal conductor inside, and having an exposed portion where a part of the internal conductor is exposed on the outer surface;
Plating the ceramic body and depositing a Cu plating film on the exposed portion of the internal conductor;
A method of manufacturing a multilayer ceramic electronic component, comprising: heat-treating the ceramic body, and generating a Cu liquid phase, an O liquid phase, and a Cu solid phase between the Cu plating film and the ceramic body.   The method for manufacturing a multilayer ceramic electronic component according to claim 13, wherein the heat treatment is performed under conditions of a temperature of 1065 ° C. or more and an oxygen concentration of 50 ppm or more.

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