JP2008251630A - Electronic component manufacturing method and electronic component - Google Patents

Abstract

An electronic component and a method of manufacturing the same are provided that can prevent plating elongation from occurring when a plating process is performed without increasing the number of manufacturing steps and manufacturing costs.
In this method of manufacturing an electronic component, a second metal electrode layer and a third metal electrode layer are formed by forming a glass layer on the edge of a first metal electrode layer on the surface of a ceramic body. The plating elongation at the time of forming the metal electrode layer 36 can be prevented. The glass layer 40 is simultaneously with baking of the first metal electrode layer 32 by shrinking the metal material derived from the substantially spherical powder and the scaly powder contained in the conductive paste to the inside of the predetermined region. It is formed. For this reason, the glass layer 40 which prevents generation | occurrence | production of plating elongation can be formed, without causing the increase in a manufacturing man-hour and manufacturing cost.
[Selection] Figure 2

Description

  The present invention relates to a method for manufacturing an electronic component including a ceramic body, and an electronic component.

  As this type of electronic component, a ceramic body, a glass layer formed on the surface of the ceramic body, and an external terminal electrode on which the ceramic body is formed via the glass layer, There is known a material plated with (see, for example, Patent Document 1). In the electronic component described in Patent Document 1, the edge portion of the external terminal electrode is present inside the edge portion of the glass layer, and it is possible to prevent the occurrence of plating elongation during the plating process. it can.

Patent Document 1 describes the following manufacturing method as a method for manufacturing the electronic component described above. First, a ceramic body, a glass paste, and a conductive paste are prepared. Next, after applying and drying a glass paste on the surface of the ceramic body, the conductive paste is applied so that the peripheral edge after application is inside the peripheral edge of the layer made of the glass paste. The paste is baked to form a glass layer and external terminal electrodes. Next, electroplating is performed on the external terminal electrodes.
Japanese Patent Laid-Open No. 6-112086

  However, in the manufacturing method described in Patent Document 1, it is necessary to prepare a glass paste separately from the conductive paste, apply it to the ceramic body and dry it, increase the man-hours during manufacturing, and increase the manufacturing cost. There is a fear of becoming. Moreover, when the conductor is arrange | positioned in a ceramic body, there exists a possibility that the problem that the electrical connection of the said conductor and a terminal electrode may be inhibited by a glass layer may arise.

  The present invention has been made in order to solve the above-described problems, and an electronic component capable of preventing the occurrence of plating elongation when performing a plating process without causing an increase in manufacturing man-hours and manufacturing costs, and It aims at providing the manufacturing method.

In order to solve the above problems, a method of manufacturing an electronic component according to the present invention includes a step of preparing a ceramic body, a conductive paste containing conductive powder and glass powder, and a predetermined region on the surface of the ceramic body. A step of applying a conductive paste, a step of baking the conductive paste applied to a predetermined region to form a baked electrode layer, and a step of forming a plated electrode layer on the baked electrode layer. in preparing a paste, an amorphous glass, crystallized glass, a first metal powder having a specific surface area becomes ^{2m 2} / ^g~3m 2 / g, a specific surface area of 0.8 m ² / g to 1 Derived from the first metal powder and the second metal powder contained in the conductive paste in the step of preparing a baked electrode layer by preparing a conductive paste containing a second metal powder of .5 m ² / g Do By contracting the genus substance inside the predetermined area, and characterized by forming a glass layer on the edge of the baked electrode layer on the surface of the ceramic body.

  In this method of manufacturing an electronic component, when a plated electrode layer is formed on a baked electrode layer by forming a glass layer on the edge of the baked electrode layer on the surface of the ceramic body, from the end of the baked electrode layer. It can prevent that a plating electrode layer is extended and formed. This glass layer is formed at the same time as the baked electrode layer by shrinking the metal material derived from the first metal powder and the second metal powder contained in the conductive paste to the inside of a predetermined region. For this reason, unlike the prior art, it is not necessary to prepare a glass paste separately from the conductive paste, apply it to the ceramic body and dry it. Therefore, it is possible to form a glass layer that prevents the plating elongation from occurring without increasing the number of manufacturing steps or manufacturing costs. By including amorphous glass in the conductive paste, the shape of the glass layer during baking is maintained. In addition, by including the first metal powder and the second metal powder having different specific surface areas in the conductive paste, it is possible to suitably adjust the amount by which the metal powder shrinks inward from the predetermined region.

  In the conductive paste, the component ratio of the glass component composed of amorphous glass and crystallized glass to the metal component composed of the first metal powder and the second metal powder is 8.0 wt% to 11.0 wt%. % Is preferable. By satisfying such a range, it becomes easy to form a glass layer having a suitable shape in order to prevent plating elongation.

  In the conductive paste, it is preferable that the first metal powder is contained more than the second metal powder. In this case, shrinkage of the metal powder to the inside of the predetermined region can be generated more reliably.

  Further, the conductive paste preferably contains more crystallized glass than amorphous glass. In this case, the shape of the glass layer can be easily maintained.

  In addition, a conductor is arranged inside the ceramic body so that the end thereof is exposed on the surface of the ceramic body, and the conductor is exposed in a region where the metal powder contracts inward from a predetermined region. It is preferable that the part which contains is included. In this case, the electrical connection between the conductor disposed inside the ceramic body and the baked electrode layer can be prevented from being obstructed by the glass layer.

  The ceramic body is preferably made of a semiconductor ceramic.

The electronic component according to the present invention has a ceramic body, conductive powder, amorphous glass, crystallized glass, and a specific surface area of 2 m ² / g to ³ m ² in a predetermined region on the surface of the ceramic body. a first metal powder comprising a / g, a specific surface area of 0.8 m ² /G～1.5M baked electrode layer formed by baking a conductive paste containing a second metal powder comprising a ² / g And by shrinking the metal material derived from the first metal powder and the second metal powder contained in the conductive paste to the inside of a predetermined region, the edge of the baked electrode layer is formed on the surface of the ceramic body. It is characterized by comprising a formed glass layer and a plated electrode layer formed on the baked electrode layer.

  In this electronic component, by providing a glass layer at the edge of the baked electrode layer on the surface of the ceramic body, when the plated electrode layer is formed on the baked electrode layer, the plated electrode layer is formed from the end of the baked electrode layer. It can be prevented from being stretched. This glass layer is formed at the same time as the baked electrode layer by shrinking the metal material derived from the first metal powder and the second metal powder contained in the conductive paste to the inside of a predetermined region. As in the prior art, it is not necessary to prepare a glass paste separately from the conductive paste, apply it to the ceramic body and dry it. Therefore, it is possible to form a glass layer that prevents the plating elongation from occurring without increasing the number of manufacturing steps or manufacturing costs. By including amorphous glass in the conductive paste, the shape of the glass layer during baking is maintained. In addition, by including the first metal powder and the second metal powder having different specific surface areas in the conductive paste, it is possible to suitably adjust the amount by which the metal powder shrinks inward from the predetermined region.

  According to the electronic component manufacturing method and the electronic component according to the present invention, it is possible to prevent the plating elongation from occurring when the plating process is performed without increasing the number of manufacturing steps and the manufacturing cost.

  DESCRIPTION OF EMBODIMENTS Hereinafter, preferred embodiments of an electronic component manufacturing method and an electronic component according to the present invention will be described in detail with reference to the drawings.

  First, the configuration of a multilayer chip varistor according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a perspective view of the multilayer chip varistor according to the present embodiment. FIG. 2 is a view for explaining a cross-sectional configuration of the multilayer chip varistor according to the present embodiment.

  As shown in FIGS. 1 and 2, the multilayer chip varistor 1 includes a ceramic body (varistor body) 10 and two external electrodes 30.

  The ceramic body 10 is a sintered body made of semiconductor ceramic and exhibiting voltage non-linear characteristics (varistor characteristics), and is configured as a laminated body in which a plurality of varistor layers are laminated. In an actual multilayer chip varistor, the plurality of varistor layers are integrated to such an extent that the boundary between them cannot be visually recognized.

  The varistor layer contains ZnO (zinc oxide) as a main component and also includes rare earth metal elements, Co, group IIIb elements (B, Al, Ga, In), Si, Cr, Mo, alkali metal elements (K, K) as subcomponents. Rb, Cs) and simple earth metals such as alkaline earth metal elements (Mg, Ca, Sr, Ba) and element bodies containing these oxides. In the present embodiment, the varistor layer contains Pr, Co, Cr, Ca, Si, K, Al, and the like as subcomponents.

  In the present embodiment, Pr is used as the rare earth metal. Pr is a material for expressing varistor characteristics. The reason why Pr is used is that the voltage non-linearity is excellent and the characteristic variation at the time of mass production is small.

  In the present embodiment, Ca is used as the alkaline earth metal element. Ca becomes a material for controlling the sinterability of the ZnO-based varistor material and improving the moisture resistance. The reason for using Ca is to improve voltage nonlinearity.

  Although content of ZnO in a varistor layer is not specifically limited, When the whole material which comprises a varistor layer is 100 mass%, it is 99.8-69.0 mass% normally. The thickness of the varistor layer is, for example, about 5 to 60 μm.

  In the ceramic body 10, alkali metal is diffused from the outer surface side, and high resistance in the vicinity of the outer surface of the ceramic body 10 is achieved. When the alkali metal is diffused from the outer surface side of the ceramic body 10, the diffused alkali metal is dissolved in the ZnO crystal.

  As a result, ZnO, which exhibits properties as an n-type semiconductor, has donors reduced by alkali metal and increases electrical resistance. It is also considered that the electrical resistance is increased by the presence of an alkali metal at the grain boundary of ZnO. In the present embodiment, Li is used as the alkali metal diffused in the ceramic body 10.

  A plurality of internal electrodes 20 are arranged in the ceramic body 10 so as to face each other with at least one varistor layer interposed therebetween. The plurality of internal electrodes 20 are alternately drawn out to two opposing end faces of the ceramic body 10. That is, the end portion of the internal electrode 20 is exposed on the end surface.

  The internal electrode 20 includes a conductive material that is usually used as an internal electrode of a laminated electric element. The conductive material included in the internal electrode 20 is not particularly limited, but is preferably made of Pd, an Ag—Pd alloy, or Ag. The thickness of the internal electrode 20 is, for example, about 0.5 to 5 μm.

  The external electrode 30 is disposed on the surface of the ceramic body 10. The external electrode 30 has a first metal electrode layer 32 (baked electrode layer), a second metal electrode layer 34 (plated electrode layer), and a third metal electrode layer 36 (plated electrode layer). Yes.

  The first metal electrode layer 32 contains a metal (for example, Ag) as a main component. The first metal electrode layer 32 is formed in a region inside a predetermined region on the surface of the ceramic body 10, that is, in a region closer to the end face side of the ceramic body 10 than the glass layer 40 (described later). And physically and electrically connected.

  The first metal electrode layer 32 applies a conductive paste containing conductive powder (eg, Ag powder) and glass powder (eg, glass frit) to the predetermined region on the surface of the ceramic body 10, It is formed by baking. The thickness of the first metal electrode layer 32 is, for example, 10 to 30 μm.

  The second metal electrode layer 34 contains Ni as a main component. The second metal electrode layer 34 is formed on the first metal electrode layer 32 so as to cover the first metal electrode layer 32. The second metal electrode layer 34 is formed by plating the surface of the first metal electrode layer 32 with Ni. The thickness of the second metal electrode layer 34 is, for example, 1 to 5 μm.

  The third metal electrode layer 36 contains Sn or Sn alloy as a main component. The third metal electrode layer 36 is formed on the second metal electrode layer 34 so as to cover the second metal electrode layer 34. The third metal electrode layer 36 is formed by plating the surface of the second metal electrode layer 34 with Sn or an Sn alloy. The thickness of the third metal electrode layer 36 is, for example, 1 to 5 μm.

  On the other hand, a glass layer 40 is formed on the surface of the ceramic body 10. Specifically, the glass layer 40 is formed in a region outside the edge of the first metal electrode layer 32 so as to be continuous with the first metal electrode layer 32 with a width of about 10 μm.

  The glass layer 40 is made of a glass material derived from the glass powder contained in the conductive paste for forming the first metal electrode layer 32, and the metal powder contained in the conductive paste is given to the conductive paste. It is formed by contracting inward from the region (details will be described later). The thickness of the glass layer 40 is, for example, 1 μm to 10 μm.

  Subsequently, a manufacturing process of the multilayer chip varistor 1 having the above-described configuration will be described with reference to FIGS.

  FIG. 3 is a flowchart for explaining the manufacturing process of the multilayer chip varistor according to the present embodiment. FIG. 4 is a view for explaining the manufacturing process of the multilayer chip varistor according to the present embodiment.

  First, after weighing ZnO, which is a main component constituting the varistor layer, and trace additives such as Pr, Co, Cr, Ca, Si, K, and Al metals or oxides so as to have a predetermined ratio. The varistor material is prepared by mixing the components (S101).

  Then, an organic binder, an organic solvent, etc. are added to this varistor material, and it mixes and grinds for about 20 hours using a ball mill etc., and obtains a slurry. Examples of the organic binder include ethyl cellulose and polyvinyl butyral. Examples of the organic solvent include terpione, butyl carbitol, acetone, toluene and the like.

  Next, the slurry is applied onto a film made of, for example, polyethylene terephthalate by a known method such as a doctor blade method, and then dried to form a film having a thickness of about 30 μm. The film thus obtained is peeled from the film to obtain a green sheet (S103).

  Next, a plurality of electrode portions corresponding to the internal electrodes 20 (a number corresponding to the number of divided chips described later) are formed on the green sheet (S105). The electrode portion corresponding to the internal electrode 20 is formed by printing a conductive paste containing Pd particles as a main component, an organic binder and an organic solvent by a printing method such as screen printing and drying. .

  After the electrode portion corresponding to the internal electrode 20 is formed, each green sheet on which the electrode portion is formed and the green sheet on which the electrode portion is not formed are stacked in a predetermined order to form a sheet laminate (S107). . The sheet laminate obtained in this way is cut into chips, for example, to obtain a plurality of divided green bodies LS1 (see FIG. 4) (S109). In the obtained green body LS1, the green sheet GS1 in which the electrode portion EL1 corresponding to the internal electrode 20 is formed and the green sheet GS2 in which the electrode portion EL1 is not formed are sequentially stacked.

  Next, the green body LS1 is subjected to heat treatment at 180 to 400 ° C. for about 0.5 to 24 hours to remove the binder, and then further fired at 850 to 1400 ° C. for about 0.5 to 8 hours. (S111) to obtain the ceramic body 10. By this firing, the green sheets GS1 and GS2 in the green body LS1 become varistor layers. The electrode portion EL1 becomes the internal electrode 20.

  Next, Li is diffused from the outer surface of the ceramic body 10 (S113). Here, a Li compound is first attached to the surface of the obtained ceramic body 10. A sealed rotating pot can be used for adhesion of the Li compound. Although it does not specifically limit as a Li compound, Li is a compound in which Li can be diffused from the outer surface of the ceramic body 10 to the inside by heat treatment, and Li oxide, hydroxide, chloride, nitrate, borate, Carbonates and oxalates are used.

  Then, the ceramic body 10 to which the Li compound is attached is heat-treated in an electric furnace at a predetermined temperature and time. As a result, Li diffuses from the outer surface of the ceramic body 10 into the ceramic body 10 from the Li compound. The heat treatment temperature is, for example, 700 ° C. to 1100 ° C., and the heat treatment atmosphere is air. The heat treatment time (holding time) is, for example, 10 minutes to 4 hours.

  Next, the first metal electrode layer 32 and the glass layer 40 are formed on the surface of the ceramic body 10 (S115). In forming the first metal electrode layer 32 and the glass layer 40, first, a predetermined region on the surface of the ceramic body 10 (two end faces of the ceramic body 10 and four ends extending so as to connect the two end faces). A conductive paste is applied to the end portion of the side surface so as to be in contact with the corresponding internal electrode 20.

As described above, the conductive paste is obtained by mixing glass powder (for example, glass frit, etc.), an organic binder, and an organic solvent with conductive powder mainly composed of Ag powder. The Ag powder includes a substantially spherical powder (first metal powder) and a scaly powder (second metal powder). Powder substantially spherical shape, a specific surface area represented by BET value has become a 2.0m ² /g~3.0m ² / g, scaly powder, the specific surface area represented by BET value 0 It has become a .8m ² /g~1.5m ² / g.

  The BET value is a value determined by the BET method (Brunauer-Emmett-Teller Method), and is the total surface area per unit weight (1 g) of the raw material powder expressed in units of square meters. Generally, if the raw material powder is made finer, the surface area becomes larger, and the BET value also becomes higher. Also, the higher the BET value, the greater the amount of shrinkage during baking. The above-mentioned conductive paste contains more substantially spherical powder than scale-like powder. That is, the weight ratio between the substantially spherical powder and the scaly powder is in the range of 50:50 to 100: 0.

The glass powder contains amorphous glass and crystallized glass. As the crystallized glass, for example, B ₂ O ₃ , Bi ₂ O ₃ , Al ₂ O ₃ , and an alkaline earth metal oxide are used as constituents, or BaO, TiO ₂ , Al ₂ O ₃ , SrO, Na ₂ O, using which a component of CaO and the like. The average particle diameter of the glass powder is, for example, in the range of 1.0 to 7.0 μm. The softening point temperature of the glass powder is, for example, in the range of 580 to 680 ° C.

  In the conductive paste, the crystallized glass is contained more than the amorphous glass. That is, the weight ratio of crystallized glass to amorphous glass is in the range of 50:50 to 100: 0. Moreover, the component ratio of the glass component consisting of amorphous glass and crystallized glass to the metal component consisting of substantially spherical powder and scale-like powder is in the range of 8.0 wt% to 11.0 wt%. Yes.

  After applying such a conductive paste, it is dried to form an electrode portion corresponding to the external electrode 30. The application of the conductive paste can be performed by a dipping method, a printing method, a transfer method, or the like. The drying temperature is, for example, 80 ° C. to 150 ° C., and the drying time is, for example, 0.2 hours to 1.5 hours. Further, the ceramic body 10 on which the electrode portion is formed is subjected to a desired heat treatment to remove the binder. The heating temperature is, for example, 300 ° C. to 500 ° C., and the heating time is, for example, 0.2 hours to 1.5 hours.

  Then, a desired heat treatment is performed on the ceramic body 10 on which the electrode portions are formed, and the conductive paste is baked onto the ceramic body 10. As a result, the first metal electrode layer 32 is formed on the ceramic body 10. The heating temperature is, for example, 600 ° C. to 800 ° C., and the heating time is, for example, 0.2 hours to 1.5 hours.

  Here, when the first metal electrode layer 32 is formed by baking the conductive paste on the ceramic body 10, the glass layer 40 is simultaneously formed. The glass layer 40 is formed by shrinking the metal substance derived from the substantially spherical powder and the scaly powder contained in the conductive paste to the inside of the predetermined region described above.

  The mechanism by which the glass layer 40 is formed is considered as follows.

  First, as shown in FIG. 5A, when the conductive paste applied to the ceramic body 10 is dried and the organic solvent is removed, the substantially spherical powder M1, the scaly powder M2, and the amorphous glass A film of a mixture of the powder G1, the crystallized glass powder G2, and the organic binder B is formed. When the binder is removed, the metal powder M1, M2 and the glass powder G1, G2 are mainly attached to the ceramic body 10 as shown in FIG.

  Further, when the conductive paste is baked, as shown in FIG. 5 (c), the glass powders G1 and G2 are softened near the softening point temperature of the glass powders G1 and G2, and the metal powders M1 and M2 are baked together. I will conclude. It shrinks to the inner side (end face side of the ceramic body 10) than the predetermined region.

  When the heating further proceeds, as shown in FIG. 5 (d), the metal material made of the sintered body of the metal powders M1 and M2 contracts to the inner side (end face side of the ceramic body 10) than the predetermined region, One metal electrode layer 32 is formed. The glass material in which the glass powders G1 and G2 are softened and melted forms a layer GL in which the glass phase and the metal phase are mixed on the back side of the first metal electrode layer 32, and the first metal electrode layer 32. The glass layer 40 is formed by remaining in a state in which a certain shape is maintained outside the edges.

  After forming the first metal electrode layer 32 and the glass layer 40 in this way, the second metal electrode layer 34 is formed by electroplating (S117). In the present embodiment, Ni plating is used as the electroplating for forming the second metal electrode layer 34. Ni plating can be performed by a barrel plating method using a Ni plating bath (for example, a Watt bath).

  Finally, the third metal electrode layer 36 is formed by electroplating (S119). In the present embodiment, Sn plating is used as the electroplating for forming the third metal electrode layer 36. Sn plating can be performed by a barrel plating method using a Sn plating bath (for example, a neutral Sn plating bath). Thereby, the multilayer chip varistor 1 described above is obtained.

  As described above, in this method of manufacturing an electronic component, the glass layer 40 is formed on the edge of the first metal electrode layer 32 on the surface of the ceramic body 10, thereby forming the first metal electrode layer 32 on the first metal electrode layer 32. When the second metal electrode layer 34 and the third metal electrode layer 36 are formed by plating, the second metal electrode layer 34 and the third metal electrode layer 36 extend from the end of the first metal electrode layer 32. The plating elongation formed can be prevented.

  This glass layer 40 is formed by shrinking the metal material derived from the substantially spherical powder and the scaly powder contained in the conductive paste to the inside of a predetermined region, thereby baking the first metal electrode layer 32. Formed simultaneously. Therefore, unlike the prior art, it is not necessary to prepare a glass paste separately from the conductive paste, apply it to the ceramic body, and dry it. Therefore, it is possible to form the glass layer 40 that prevents the plating elongation from occurring without increasing the number of manufacturing steps and the manufacturing cost.

Further, in the manufacturing method of the electronic component, the conductive paste, a substantially spherical powder M1 the specific surface area is 2.0m ² /g~3.0m ² / g, a specific surface area of 0.8 m ² / g A scaly powder M2 having a concentration of ˜1.5 m ² / g is used. When a metal powder having a specific surface area larger than this range is used, the shrinkage amount of the metal material and the shrinkage difference of the metal material derived from each powder become excessive, and there is a possibility that the first metal electrode layer 32 may be cracked. .

  In addition, when a metal powder having a specific surface area smaller than this range is used, the shrinkage amount of the metal substance is insufficient, and the width of the glass layer 40 may not be sufficiently formed. Therefore, the shrinkage amount of the metal material can be optimized by satisfying the above range. Furthermore, the substantially spherical powder M1 is contained more than the scaly powder M2. By containing a large amount of powder having a substantially spherical shape M1 having a high BET value, it is possible to ensure a sufficient amount of contraction of the metal substance during baking.

  The component ratio of the glass component composed of the amorphous glass powder G1 and the crystallized glass powder G2 to the metal component composed of the substantially spherical powder M1 and the scaly powder M2 is 8.0% by weight to 11.1%. It is in the range of 0% by weight. When the component ratio of the glass component is larger than this range, the shape retention of the glass layer 40 is lowered, and the glass layer 40 may be excessively diffused on the surface of the ceramic body 10. In this case, plating may be difficult when forming the second metal electrode layer 34 and the third metal electrode layer 36.

  Moreover, when the component ratio of the glass component is made smaller than this range, there is a possibility that the glass layer 40 having a sufficient width cannot be obtained. Therefore, by satisfying the above range, it is possible to form the glass layer 40 having the optimum shape and dimension for preventing the plating elongation. Further, the crystallized glass powder M2 is more contained than the amorphous glass powder M1. Thereby, the improvement of the shape retainability of the glass layer 40 is achieved.

  In the multilayer chip varistor 1, a plurality of internal electrodes 20 are arranged inside the ceramic body 10 so that the end portions thereof are exposed on the surface of the ceramic body 10, so that the metal material is contained in a predetermined region. Further, the region contracted inward includes a portion where the internal electrode 20 is exposed. Thereby, the electrical connection between the internal electrode 20 and the first metal electrode layer 32 is not hindered by the glass layer 40.

  In the multilayer chip varistor 1, the ceramic body 10 is made of a semiconductor ceramic. In such a semiconductor ceramic, there is a problem that the plating elongation is relatively easily generated. However, the formation of the glass layer 40 almost certainly prevents the occurrence of the plating elongation.

  The present invention is not limited to the above embodiment, and various modifications can be made without departing from the scope of the invention. For example, in this embodiment, a multilayer chip varistor and a method for manufacturing the multilayer chip varistor have been described as an example of an electronic component. However, the electronic component having a ceramic body is not particularly limited. For example, a multilayer chip capacitor, The present invention can also be applied to a multilayer actuator or a multilayer chip inductor.

It is a perspective view of the multilayer chip varistor according to the present embodiment. It is a figure for demonstrating the cross-sectional structure of the multilayer chip varistor which concerns on this embodiment. It is a flowchart for demonstrating the manufacturing process of the multilayer chip varistor concerning this embodiment. It is a figure for demonstrating the manufacturing process of the multilayer chip varistor concerning this embodiment. It is a schematic diagram for demonstrating the formation process of a 1st metal electrode layer.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Multilayer chip varistor, 10 ... Ceramic body, 20 ... Internal electrode (conductor), 30 ... External electrode, 32 ... 1st metal electrode layer (baking electrode layer), 34 ... 2nd metal electrode layer (plating) Electrode layer), 36 ... third metal electrode layer (plating electrode layer), 40 ... glass layer, G1 ... amorphous glass powder, G2 ... crystallized glass powder, M1 ... substantially spherical powder (first electrode) Metal powder), M2 ... scaly powder (second metal powder).

Claims (7)

Preparing a ceramic paste and a conductive paste containing conductive powder and glass powder;
Applying the conductive paste to a predetermined region on the surface of the ceramic body;
Baking the conductive paste applied to the predetermined region to form a baked electrode layer;
Forming a plating electrode layer on the baking electrode layer,
In the step of preparing the conductive paste, and the amorphous glass, crystallized glass, a first metal powder having a specific surface area becomes 2.0m ² /g~3.0m ² / g, specific surface area 0 .8m ² /g~1.5m prepared conductive paste and a second metal powder comprising a ² / g,
In the step of forming the baking electrode layer, by shrinking the metal material derived from the first metal powder and the second metal powder contained in the conductive paste to the inside of the predetermined region, A method of manufacturing an electronic component, comprising: forming a glass layer on an edge of the baked electrode layer on the surface of the ceramic body.   In the conductive paste, a component ratio of the glass component composed of the amorphous glass and the crystallized glass to the metal component composed of the first metal powder and the second metal powder is 8.0% by weight to 11%. 2. The method of manufacturing an electronic component according to claim 1, wherein the content is in the range of 0.0% by weight.   3. The method of manufacturing an electronic component according to claim 1, wherein the conductive paste contains more of the first metal powder than the second metal powder. 4.   The method for manufacturing an electronic component according to claim 1, wherein the conductive paste contains more of the crystallized glass than the amorphous glass. Inside the ceramic body, a conductor is disposed so that an end thereof is exposed on the surface of the ceramic body,
5. The electronic component manufacturing according to claim 1, wherein the region in which the metal powder shrinks inward from the predetermined region includes a portion where the conductor is exposed. Method.   The method of manufacturing an electronic component according to claim 1, wherein the ceramic body is made of a semiconductor ceramic. A ceramic body,
Wherein a predetermined region on the surface of the ceramic body, a conductive powder, an amorphous glass, the first crystallization and glass, the specific surface area is 2.0m ² /g~3.0m ² / g metal powder and a specific surface area of 0.8m ² /g~1.5m ² / g and comprising a second metal powder and the baked electrode layer formed by baking a conductive paste containing,
The metal material derived from the first metal powder and the second metal powder contained in the conductive paste is shrunk on the surface of the ceramic body by shrinking the metal material to the inside of the predetermined region. A glass layer formed on the edge of the electrode layer;
An electronic component comprising: a plating electrode layer formed on the baking electrode layer.

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