JPH11288839A - Laminated chip type electronic component and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide normal mounting directivity, to eliminate a solder fillet projected to the side part of a component main body, to set a loading interval for mutually adjacent electronic components narrow and to perform high density mounting, capable of more effective utilization of the area of the limited plate surface of a circuit board. SOLUTION: An electronic component main body 1 is formed by alternately laminating internal electrodes 2, 2', and so on and a dielectric layer and the parts 2a, 2b, 2a' and 2b' of the end faces of the internal electrodes 2 and 2' which are not electrically connected to each other are separately exposed within respective surfaces near both end parts of the component main body 1 which is parallel to the end faces. External connection electrodes 3a, 3b, 4a and 4b electrically connected to the parts 2a, 2b, 2a' and 2b' of the end faces of the internal electrodes 2 and 2', while keeping a distance within the respective surfaces from the outer peripheral edge of the component main body 1, are provided respectively in the same form on the respective upper and lower surfaces of the component main body 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a component body which is formed by alternately laminating internal electrodes and dielectric layers, and externally connecting electrodes which are electrically connected to the internal electrodes. The present invention relates to a multilayer chip type electronic component mounted on a board surface of a circuit board by soldering and fixing, and a method of manufacturing the same.

[0002]

2. Description of the Related Art In general, when a multilayer chip capacitor is exemplified, an internal electrode and a dielectric layer are alternately stacked up and down to form a rectangular parallelepiped component body, and ends of the internal electrode exposed at both ends of the component body. External electrodes are provided at both ends of the component body so as to be electrically connected to the component. The external electrode is formed so as to cover both ends of the component body from an end surface portion electrically connected to the end portion of the internal electrode and a peripheral surface portion turning from the end surface portion to a surface near an end edge of the component body. ing.

[0003] For mounting the multilayer chip capacitor,
Mainly, since it is fixed by soldering to the end face portion of the external electrode, a land portion of the conductive pattern is provided on the board surface of the circuit board so as to extend laterally from both end edges of the mounted component body. . In this circuit board, when the multilayer chip capacitor is soldered to the board surface, the solder paste printed on the lands of the conductive pattern swells and aggregates due to surface tension along the end surfaces of the external electrodes, and the solder fillet is formed on the component body. It is formed to protrude from both ends.

In this case, adjacent electronic components must be mounted on the board surface of the circuit board, apart from the solder fillet, together with the land portions of the conductive pattern that extend to the side of the component body. This hinders high-density mounting of a plurality of components within a limited area of the board surface of the circuit board.

A surface-mount type electronic component has been proposed in which external electrodes are provided on the surface of the component main body opposite to the board surface of the circuit board, instead of covering both ends of the component main body described above (Japanese Patent Laid-Open No. Hei 2 (1994)). -156514).

In this electronic component, since the external electrodes are only provided on one surface of the component body, the mounting direction is limited to one direction. Therefore, in order to mount the electronic component on the board surface of the circuit board, a process of aligning the surface on which the external electrodes are formed with the board side is required, and a commonly used electronic component surface mounting apparatus is used. May not be used.

In addition, in the above-described electronic component, the external electrodes are disposed on the surface of the component body facing the plate surface of the circuit board.
The periphery is provided near the end so as to match the outer edge of the component body. Also, in consideration of the solder paste aggregating around the end surface of the external electrode, the land portion of the conductive pattern is formed on the board surface of the circuit board so as to extend laterally from the component body. For this reason, it is inevitable that a solder fillet still protrudes to the side of the component body.

In order to manufacture the electronic component, a plurality of dielectric blocks are obtained by alternately laminating a plurality of internal electrodes and dielectric green sheets, and a plurality of dielectric blocks are obtained. Obtain an element body in which the ends of the internal electrodes are exposed on at least one surface of the element body surface by cutting for each unit, and apply a conductive paste for forming external electrodes to each row of end rows of the internal electrodes in many rows. It has been proposed that the element body be cut into individual component element units, and then the component element be fired together with a conductive paste (Japanese Patent Laid-Open No. 9-260187).
issue).

[0009] However, in the method of manufacturing an electronic component, since cutting chips generated as a result of cutting the element body adhere to and remain on the previously applied conductive paste, it is difficult to accurately form the external electrodes. In addition, the difference in firing shrinkage between the dielectric layer and the external electrode during firing deteriorates the electrical connectivity with the internal electrode and affects the electrical characteristics. Also, at the same time as the component element body, the external electrodes are also required for firing the component element body.
Since the heat treatment is performed at a high temperature of 0 ° C. or more, a conductive paste containing a glass frit and a silver electrode paste that are generally used cannot be used.

[0010]

SUMMARY OF THE INVENTION The present invention has a normal mounting direction and eliminates the solder fillet protruding to the side of the component body, thereby making it possible to narrow the mounting interval between adjacent electronic components. It is another object of the present invention to provide a multilayer chip-type electronic component suitable for high-density mounting that can more effectively utilize the limited area of the circuit board.

An object of the present invention is to provide a method of manufacturing a laminated chip electronic component capable of accurately forming external connection electrodes from a commonly used conductive paste without impairing electrical characteristics.

Further, the present invention provides a method of manufacturing a laminated chip type electronic component capable of forming an electrical component having good electrical characteristics by securely connecting the end of an internal electrode and an external connection electrode. With the goal.

It is a further object of the present invention to provide a method for manufacturing a laminated chip type electronic component capable of forming external connection electrodes efficiently and easily.

[0014]

According to a first aspect of the present invention, there is provided a multilayer chip type electronic component in which a plurality of internal electrodes and dielectric layers are alternately laminated to form a component body.
Part of the end faces of the internal electrodes that are not electrically connected to each other,
Near each end of the component body parallel to its end face, it is separated and exposed in each plane, and is electrically connected to each end of the internal electrode at a distance within each plane from the outer peripheral edge of the component body. The external connection electrodes are formed in the same form on the upper and lower surfaces of the component body.

According to a second aspect of the present invention, there is provided a method of manufacturing a multilayer chip type electronic component, wherein a plurality of internal electrodes and dielectric green sheets are alternately laminated to obtain a multi-cavity laminate. The body is individually cut into component body units and then fired, and a part of the end faces of the internal electrodes that are not electrically connected to each other are separated in each plane near both ends of the component body parallel to the end faces. After obtaining the exposed component body, the external connection electrodes that are electrically connected to each end of the internal electrode while maintaining a distance within each plane from the outer peripheral edge of the component body are the same on each of the upper and lower surfaces of the component body. It is adapted to be formed into a form.

In the method of manufacturing a multilayer chip electronic component according to a third aspect of the present invention, each surface of the component body in which each end of the internal electrode is exposed is ground and then fired to form the external connection electrode. It is formed on each surface of the ground component body.

In the method of manufacturing a multilayer chip electronic component according to a fourth aspect of the present invention, a plurality of fired component bodies are aligned and held by a jig, and a conductive paste is applied to upper and lower surfaces of the component body. Then, the conductive paste is baked to form external connection electrodes.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the accompanying drawings, the illustrated embodiment is a typical example of a multilayer chip electronic component such as a multilayer chip capacitor, a chip resistor, a chip inductor, and a chip filter. 1 shows a multilayer chip capacitor (hereinafter simply referred to as “chip component”). As shown in FIGS. 1 and 2, the component body 1 is formed by alternately laminating a plurality of dielectric layers (not numbered, the same applies hereinafter) and the internal electrodes 2, 2 '. Are formed so as to have a rectangular parallelepiped shape.

The component body 1 is formed by alternately laminating dielectric layers and internal electrodes 2, 2 '..., And a part 2a, 2b, 2 of the end face of the internal electrodes 2, 2'.
The components a 'and 2b' are formed by exposing the components a in a plane near both ends parallel to the end faces thereof. The internal electrodes 2, 2 '... Are formed by a T-shaped electrode pattern in which each end 2a, 2b, 2a', 2b 'is drawn out to the upper and lower surfaces of the component body 1 as described in detail later. It can be formed by printing on a dielectric green sheet to be a layer, and laminating a plurality of dielectric green sheets each having an electrode pattern printed in the opposite direction.

In the component body 1, a pair of left and right external connection electrodes 3a, 3b, 4a, 4b are provided on the upper and lower surfaces of the component body 1 as shown in FIG. The pair of external connection electrodes 3a, 3b, 4a, 4b are part of the end surfaces 2a, 2a,
2b, 2a ', 2b' and each intended individually electrically connected, the distance to each plane of the outer periphery of the component body 1 L _1, L ₂
While maintaining the same shape on the upper and lower surfaces of the component body 1.

For mounting the chip component, the circuit board P
As shown in FIG. 1, each pair of external connection electrodes 3a, 3
The land portions R ₁ , R _{2 of the} conductive pattern are printed and formed so as to be positioned so as to cross over the lines b, 4a, 4b. The land portions R ₁ and R ₂ are made of solder paste on the external connection electrodes 3 a and 3.
In consideration of aggregation around the thickness plane of b, 4a, 4b,
External connection electrodes 3a, 3b, 4a, 4b to form spread in a wider area than the external connection electrodes 3a, 3b, 4a, 4b within the range of the distance L _1, L ₂ that separates from the outer sides of the component body 1 inside be able to. The board surface of the circuit board P is covered with a solder resist film (not shown) except for the land portions R ₁ and R ₂ of the conductive pattern.

The above-mentioned chip component can be fixed by soldering to the plate surface of the circuit board P by reflow soldering. In this reflow soldering, first, cream solder is printed on the lands R ₁ and R ₂ of the conductive pattern. Next, the chip component is placed on the plate surface of the circuit board P. Since the external connection electrodes 3a, 3b, 4a, and 4b are provided on the upper and lower surfaces of the component body 1 in the same form, the chip component is mounted. The external connection electrodes 3a, 3 can be placed on the circuit board P from any one of the upper and lower surfaces of the component body 1.
b or 4a, 4b can be temporarily fixed by contacting with cream solder. Similarly, if other electronic components are also mounted on the board surface of the circuit board P, the soldering process may be performed by sending the electronic components to an infrared irradiation furnace and melting the cream solder.

During this soldering process, the solder fillets S ₁ and S ₂ are formed by melting and solidifying the cream solder. The solder fillets S ₁ and S ₂ are located inside the outer side of the component body 1. External connection electrode 3 located at a distance
a, 3b or 4a, 4b, it does not protrude at least laterally from the component body 1. The solder fillets S ₁ and S ₂ are connected to the external connection electrodes 3a and 3b.
Alternatively, even if the agglomerates around the thickness planes of 4a and 4b, they do not exceed the area of the lands R ₁ and R ₂ and do not protrude from the component body 1 to the side.

Therefore, according to the chip component having the above-described configuration, not only the land portions R ₁ and R ₂ of the conductive pattern need not be formed so as to extend laterally than the component body 1 on the board surface of the circuit board P, but also. Since the solder fillets S ₁ and S ₂ do not protrude to the side from the component body 1, the mounting positions of the adjacent electronic components or the lands of the conductive patterns can be set at narrower positions closer to the component body 1. . This makes it possible to effectively utilize the limited area of the board surface of the circuit board and configure a multilayer chip electronic component that can be mounted at high density.

To manufacture this chip component, first, a green sheet is obtained from a dielectric material paste, and then an internal electrode is screened with a conductive paste such as Cu, Ag, Pd, or Ni on the sheet surface of the dielectric green sheet. An internal electrode is formed by printing. In the case of an electrode pattern having a T-shape, the internal electrodes are laterally continuous at the head side of the T-shape, and a plurality of the inner electrodes are arranged in a single row. Can be formed.

After the formation of the internal electrodes, the dielectric green sheet is formed by laminating a plurality of layers 1a, 1b... Alternately with the internal electrodes 2, 2 '... As shown in FIG. In this lamination, the internal electrodes 2, 2 'are positioned so as to form an electrode pattern in the opposite direction between the upper and lower dielectric green sheets 1a, 1b,... By doing so, it is formed as a multilayer body 1 'for multi-cavity production. Although not particularly shown, a dielectric protective layer is laminated on the outermost layer of the laminate 1 '.

The laminate 1 'is cut into individual parts as shown in FIG. This cutting is performed in the direction in which the head side of the T-shape is continuous in the lateral direction, and the cutting direction C ₁ for each T-head side and the cutting direction C _{2 for} each T-shape formed in a plurality of rows. , The inner electrodes 2, 2 ′ that are not electrically connected to each other
It is possible to obtain a component body in which a, 2b, 2a ', and 2b' are exposed near both ends in each of the upper and lower surfaces. Further, since the cutting is performed in a green state in which the laminate 1 ′ is not fired, it can be easily performed using a normal straight-blade-shaped slicer.

After cutting into component parts, grinding is performed so that part of the end face of the internal electrode is exposed. Thereafter, each component body is subjected to a firing process by being sent to a firing furnace. The firing process is performed at a temperature of about 1000 to 1400 ° C., and the dielectric layers are integrally sintered. Thereby, parts 2a, 2b, 2a ', 2b' of the end faces of the internal electrodes 2, 2 'which are not electrically connected to each other as shown in FIG. 2 are exposed near both ends in each of the upper and lower surfaces. The component body 1 can be obtained.

An external connection electrode is formed by applying a conductive paste such as Ag, Cu or the like to the component bodies 1, 1... As shown in FIG. 6, the electrodes are formed by pallet-shaped jigs 10 for accommodating a plurality of component bodies 1, 1,... In recesses 10a, 10b. Are turned over by a jig 10 using a metal mask 11 having openings 11a, 11b... Corresponding to the respective ends of the internal electrodes to be formed, and a squeegee 12 for moving the conductive paste G. .. Can be printed on both sides of the component bodies 1, 1,. According to the printing process, the plurality of component bodies are
By keeping the alignment at 0, not only batch processing can be performed, but also the conductive paste G can be applied to the ground surfaces of the component bodies 1, 1,... With high accuracy.

The printed conductive paste G has 50
Baking treatment at a temperature of about 0 to 900 ° C.
n, external connection electrodes 3 by plating with solder or the like.
a, 3b, 4a, and 4b. Since the external connection electrodes 3a, 3b, 4a, and 4b are only heated at the temperature required for baking the conductive paste G, the electrical characteristics are not deteriorated, and the conduction with the internal electrodes is not caused. As described above, the external connection electrodes electrically connected to a part of the end surface of the internal electrode while maintaining a distance in each plane from the outer peripheral edge of the component main bodies 1, 1. Can be formed.

When the above-described structure and manufacturing method of a chip component are applied, a chip component having a narrow width W can be formed in balance with the height H of the component body as shown in FIG. This chip component is suitable for high-density mounting because the component can be reduced in size and height.

[0032]

As described above, according to the multilayer chip type electronic component of the first aspect of the present invention, the component main body is formed by alternately laminating a plurality of internal electrodes and dielectric layers, and the electrical components are electrically connected to each other. A part of the end face of the internal electrode which is not electrically connected is exposed in the respective planes near both ends of the component body which is parallel to the end face, and is externally connected to a part of the end face of the internal electrode. Since the connection electrodes are provided on the upper and lower surfaces of the component body in the same form, the mounting direction at the time of surface mounting is not limited. In addition, since the external connection electrodes are provided at a distance within each plane from the outer peripheral edge of the component body, do not spread laterally from the component body on the board surface of the circuit board as land portions of conductive patterns required for soldering. Often, the solder fillet does not protrude from the side of the component body, so that the limited area of the board surface of the circuit board can be effectively utilized and high-density mounting can be achieved.

According to the method for manufacturing a multilayer chip electronic component according to the second aspect of the present invention, a plurality of internal electrodes and dielectric green sheets are alternately laminated to obtain a multi-cavity laminate. After the laminate is individually cut into component element units and fired, the external connection electrodes are provided on the component surface where a part of the end face of the internal electrode is exposed, so that the conductive paste forming the external connection electrodes is baked. Since the heat treatment can be performed at a temperature required for the semiconductor device, it is possible to form a good external connection electrode without deteriorating the electrical characteristics as well as causing poor conductivity with the internal electrode.

According to the method of manufacturing a multilayer chip electronic component according to a third aspect of the present invention, the element body surface on which each end of the internal electrode is exposed is ground and then fired to grind the external connection electrode. Since the conductive paste for forming the external connection electrode is formed on the main body surface of the component main body, the conductive paste for forming the external connection electrode can be printed and formed with high precision.

According to the method of manufacturing a multilayer chip electronic component according to the fourth aspect of the present invention, the conductive paste is efficiently placed on the upper and lower sides of the component main body by aligning and holding a plurality of fired component main bodies with a jig. An external connection electrode can be easily formed by coating on each surface.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing a laminated chip type electronic component according to an embodiment of the present invention in a board mounted state.

FIG. 2 is a perspective view of a component body showing a laminated structure of internal electrodes in the multilayer chip electronic component.

FIG. 3 is a perspective view of a component main body showing a form of an external connection electrode in the multilayer chip electronic component.

FIG. 4 is an explanatory view showing a method of laminating a laminate for producing the laminated chip electronic component.

FIG. 5 is an explanatory view showing a method of cutting a laminate for producing the laminated chip electronic component.

FIG. 6 is an explanatory view showing a method of applying a conductive paste for forming external connection electrodes of the multilayer chip electronic component.

FIG. 7 is a perspective view of a component body showing a laminated structure of internal electrodes in a laminated chip electronic component according to another embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Component main body 1a, 1b ... Dielectric green sheet 1 'Laminated body 2, 2' ... Internal electrode 2a, 2b, 2a ', 2b' Part of the end surface of internal electrode 3a, 3b, 4a, 4b External connection electrode P circuit Board L ₁ , L ₂ Distance between external connection electrodes 10 Jig

Claims (4)

[Claims] 1. A component body is formed by alternately laminating a plurality of internal electrodes and dielectric layers, and a part of an end face of an internal electrode that is not electrically connected to each other is partially connected to both ends of the component body parallel to the end face. An external connection electrode that is separated and exposed in each plane near the part and that is electrically connected to a part of the end surface of the internal electrode while maintaining a distance in each plane from the outer peripheral edge of the component body. Characterized in that the upper and lower surfaces are provided in the same form, respectively. 2. An internal electrode and a plurality of dielectric green sheets are alternately laminated to obtain a multi-cavity laminated body, and the laminated body is cut into individual parts and then fired to be electrically connected to each other. A part of the end face of the internal electrode that is not connected to both ends of the component body parallel to the end face is obtained near the both ends of the component body, and the exposed component body is separated and exposed in each plane. An external connection electrode electrically connected to a part of an end face of the internal electrode while keeping a distance between the upper and lower surfaces of the component body. Production method. 3. A grinding process for each surface of the component body where each end of the internal electrode is exposed, followed by a baking process to form an external connection electrode on each surface of the ground component body. The method for manufacturing a multilayer chip electronic component according to claim 2, wherein: 4. A plurality of the baked component bodies are aligned and held by a jig, a conductive paste is applied to upper and lower surfaces of the component body, and the conductive paste is baked to form external connection electrodes. The method for manufacturing a multilayer chip electronic component according to claim 2, wherein the method is performed.