KR102057915B1 - Multilayer capacitor - Google Patents

Abstract

The present invention relates to a multilayer capacitor, in order to simultaneously realize high capacity and miniaturization of a multilayer capacitor, and to improve connection reliability between an external terminal and an internal electrode, a ceramic body in which a plurality of internal electrodes are stacked and disposed therein, and the ceramic body A multilayer capacitor comprising a pair of external terminals provided at both sides, the multilayer capacitor comprising: a first internal electrode having one end connected to one external terminal; A second internal electrode disposed to face the first internal electrode at a predetermined interval and having one end connected to the other external terminal; And a third internal electrode disposed between the internal electrodes of the upper and lower layers, wherein at least two or more sheets are sequentially stacked.

Description

Multilayer Capacitors {MULTILAYER CAPACITOR}

The present invention relates to a multilayer capacitor, and more particularly, to a high capacity and miniaturized multilayer capacitor.

In general, an electronic component using a ceramic material such as a capacitor, an inductor, a piezoelectric element, a varistor, or a thermistor is a ceramic body made of ceramic material, an internal electrode formed inside the body, and an external terminal provided on the surface of the ceramic body to be connected to the internal electrode. It is provided.

The multilayer capacitor of the ceramic electronic component includes a plurality of stacked ceramic sheets, internal electrodes disposed to face each other with one ceramic sheet interposed therebetween, and external terminals electrically connected to the internal electrodes. The multilayer capacitor is widely used as a component of a mobile communication device such as a computer, a PDA, and a mobile phone due to its small size, high capacity, and easy mounting.

In recent years, as electronic products are miniaturized and multifunctional, chip components are also miniaturized and highly functionalized. Therefore, a multilayer capacitor has a high capacity and a large capacity.

Accordingly, manufacturing methods for realizing high capacity by thinning the ceramic body and increasing the number of stacked layers or improving the design of the internal electrode have been developed. As one of them, a multilayer capacitor in which another internal electrode is disposed between internal electrodes without being connected to an external terminal is generally applied.

However, in the conventional multilayer capacitor having such a structure, in order to design a capacitor with high breakdown voltage, a unit of device thickness is required because the thickness of the ceramic layer located between the internal electrodes (hereinafter, referred to as "element thickness") must be greatly increased. As the breakdown voltage value per thickness is lowered, and as the device thickness is increased, the attainable capacitance is also lowered, and the problem of reversing the trend of miniaturization of products is occurring.

In addition, when a plurality of thick ceramic layers having a thickness of about 20 μm and less than 10 internal electrodes are stacked in the internal electrode design, the contact between the internal electrode and the external electrode is not easy and the ESR (Equivalent Serier Resistance) value is increased. It can be cause.

In addition, as the multilayer capacitor gradually decreases in size, the reliability of the connection between the internal electrode and the external electrode is lowered, thereby causing a defect such as a blister in which the external terminal is lifted from the ceramic body. This, in turn, causes a decrease in the reliability of the multilayer ceramic capacitor.

The present invention is to solve the above problems by providing a multilayer capacitor with improved connection reliability between the external terminal and the internal electrode.

In order to achieve the above object, the present invention provides a multilayer capacitor including a ceramic body having a plurality of internal electrodes disposed therein and a pair of external terminals provided at both sides of the ceramic body. A first internal electrode connected to either external terminal; A second internal electrode disposed to face the first internal electrode at a predetermined interval and having one end connected to the other external terminal; And a third internal electrode disposed between the internal electrodes of the upper and lower layers, wherein at least two or more sheets are stacked in succession.

The present invention also provides a multilayer capacitor in which at least two first internal electrodes are successively stacked.

The present invention also provides a multilayer capacitor in which at least two second internal electrodes are successively stacked.

The present invention also provides a multilayer capacitor in which at least two first and second internal electrodes are successively stacked.

Further, the multilayer capacitor according to any one of claims 2 to 4, wherein a distance t between the first internal electrodes or the second internal electrodes stacked in succession is 1 to 50 µm.

According to the multilayer capacitor according to the present invention, by stacking the first internal electrode, the second internal electrode, or the first and second internal electrodes in succession, the connection reliability between the internal electrode and the external terminal can be improved. A third internal electrode which is not connected to an external terminal is provided between the first and second internal electrodes of the layer to secure a high capacitance and at the same time reduce the size of the product.

In addition, as one end surface of the first internal electrode, the second internal electrode, or the first and second internal electrodes that are joined to the external terminals becomes wider, the contact resistance between the internal electrodes and the external terminals is reduced, and accordingly, ESR (Equivalent) Serier Resistance) and Q value characteristics can be improved.

1 is an external perspective view of a multilayer capacitor according to the present invention;
2 is a cross-sectional view of a multilayer capacitor according to the present invention.
3 is a cross-sectional view of a multilayer capacitor according to another embodiment of the present invention.
4 is a cross-sectional view of a multilayer capacitor according to another embodiment of the present invention.

Advantages and features of the present invention, techniques for achieving them, and the like will become apparent with reference to the embodiments described below in detail with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but may be implemented in various forms. This embodiment may be provided to make the disclosure of the present invention complete, and to fully inform the scope of the invention to those skilled in the art. Like reference numerals refer to like elements throughout the specification.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. In this specification, the singular also includes the plural unless specifically stated otherwise in the phrase. As used herein, 'comprise' and / or 'comprising' refers to a component, step, operation and / or element that is mentioned in the presence of one or more other components, steps, operations and / or elements. Or does not exclude additions.

1 is an external perspective view of a multilayer capacitor according to the present invention, and FIG. 2 is a cross-sectional view of the multilayer capacitor according to the present invention. In addition, the components of the drawings are not necessarily drawn to scale, and for example, the size of some of the components of the drawings may be exaggerated relative to other components to facilitate understanding of the present invention.

1 and 2, the multilayer capacitor 100 according to the present invention includes a ceramic body 110, a plurality of first to third internal electrodes 121, 122, and 123 disposed inside the ceramic body 110, And it may include a pair of external terminals 130.

The ceramic body 110 is sintered after laminating a plurality of ceramic sheets, and adjacent ceramic sheets are integrated to such an extent that boundaries cannot be identified. Here, the ceramic sheet may be made of a ceramic material having a high dielectric constant, but is not limited thereto. For example, a barium titanate (BaTiO 3) material, a lead composite perovskite material, or a strontium titanate (SrTiO 3) material may be used. Can be used.

In addition, there is no restriction | limiting in particular in the external shape and dimension of the said ceramic main body 110, According to a use, it can set suitably. Usually, the outer shape is a rectangular parallelepiped shape, and the dimension may be approximately 0.2 to 5.0 [mm] × 0.15 to 5.6 [mm] × 0.1 to 1.9 [mm] in the width × length × thickness.

The external terminal 130 is provided at both sides of the ceramic body 110 and electrically connected to one ends 121a and 122a of the first and second internal electrodes 121 and 122 exposed to the side surface of the ceramic body 110, respectively. Is connected. Therefore, when a predetermined voltage is applied to the external terminal 130, charge is accumulated between the first and second internal electrodes 121 and 122 facing each other, and the capacitance of the multilayer capacitor is determined by the first and second internal electrodes. It is proportional to the area of (121, 122).

The external terminal 130 may be formed by applying a conductive paste to the side end of the ceramic body 110, firing the ceramic body 110 coated with the conductive paste, and sintering metal powder in the conductive paste. Here, the conductive paste may include metal powder of Cu, Ag, Pt, and alloys thereof.

The first to third internal electrodes 121, 122, and 123 provided in the ceramic body 110 are formed between one ceramic sheet in a process of laminating a plurality of ceramic sheets, and are disposed between one ceramic sheet by sintering. It is formed inside the ceramic body 110. Accordingly, each internal electrode is electrically insulated from each other by the ceramic sheet.

The first to third internal electrodes 121, 122, and 123 are provided in the form of a conductive film having a predetermined pattern by screen printing on a ceramic sheet using a conductive paste. Here, the conductive paste may be formed of a metal having excellent conductivity, and the type of the conductive paste is not particularly limited. For example, silver (Ag), lead (Pb), platinum (Pt), nickel (Ni), or copper ( Cu) etc., These can be used individually or in mixture of 2 or more types.

The first internal electrode 121 and the second internal electrode 122 are a pair of electrodes having different polarities, and the first and second internal electrodes 121 and 122 are printed together on one ceramic sheet. The third internal electrode 123 is printed on one ceramic sheet different from the ceramic sheet on which the first and second internal electrodes 121 and 122 are printed. As such, the plurality of ceramic sheets on which the first and second internal electrodes 121 and 122 are printed and the plurality of ceramic sheets on which the third internal electrodes 123 are printed are alternately stacked and pressed, and then, according to a predetermined condition. When fired, the ceramic body 110 may be obtained.

Looking at the printing patterns of the first and second internal electrodes 121 and 122 in detail, each end 121a and 122a of the first and second internal electrodes 121 and 122 is exposed to the outside of the ceramic body 110. And the external terminals 130 positioned at left and right sides of the ceramic body 110, respectively.

That is, as shown in FIG. 2, one end 121a of the first internal electrode 121 is connected to an external terminal 130 provided on the left side of the ceramic body 110 and the second internal electrode ( One end 122a of the 122 may be connected to the external terminal 130 provided at the right side of the ceramic body 110. Of course, on the contrary, one end 121a of the first internal electrode 121 is connected to the external terminal 130 provided at the right side of the ceramic body 110 and one end of the second internal electrode 122 is formed. Naturally, 122a) may be connected to the external terminal 130 provided at the left side of the ceramic body 110.

The first and second internal electrodes 121 and 122 are disposed to face each other with the other ends 121b and 122b spaced apart from each other at a predetermined interval. The separation distance between the first and second internal electrodes 121 and 122 may be arbitrarily adjusted according to the length of the third internal electrode 123.

The third internal electrode 123 is disposed between the first and second internal electrodes 121 and 122 of the upper and lower layers, and is printed on the central portion of the ceramic sheet to be connected to either of the external terminals 130. I never do that.

Both ends 123a of the third internal electrode 123 overlap with the other ends 121b and 122b of the first internal electrode 121 and the second internal electrode, respectively. Accordingly, the first and second internal electrodes 121 and 122 and the third internal electrode 123 may have a plurality of capacitive components connected in series between the first internal electrode 121 and the second internal electrode 122. Can be.

The third internal electrode 123 may be designed in a form in which at least two or more sheets are successively stacked in order to obtain a higher capacity.

Similarly, the first and second internal electrodes 121 and 122 may be printed and formed on both surfaces of one ceramic sheet so that the first and second internal electrodes 121 and 122 may be continuously stacked. Alternatively, as another embodiment of the present invention, as illustrated in FIGS. 3 and 4, the first internal electrode 121 or the second internal electrode 122 may be continuously stacked.

In order to continuously stack the first internal electrode 121 (or the second internal electrode 122), a plurality of first internal electrodes 121 (or second internal electrodes 122) printed on both surfaces thereof may be formed. The ceramic sheet and the ceramic sheet on which no internal electrodes are printed are alternately stacked.

As described above, the multilayer capacitor 100 according to the present invention sequentially stacks the first internal electrode 121, the second internal electrode 122, or the first and second internal electrodes 121 and 122, thereby forming a gap between the internal electrode and the external terminal. The connection reliability is improved, and accordingly, a third internal electrode 123 which is not connected to the external terminal 130 is provided between the first and second internal electrodes 121 and 122 of the upper and lower layers, thereby ensuring high capacitance. The product can be miniaturized.

In addition, as one end surface of the first internal electrode 121, the second internal electrode 122, or the first and second internal electrodes 121 and 122 that are bonded to the external terminal 130 is widened, the internal electrode and the external The contact resistance between the terminals can be lowered, thereby improving ESR (Equivalent Serier Resistance) and Q value characteristics.

In this case, the larger the number of the first internal electrodes 121 (or the second internal electrodes 122) stacked in succession becomes, the above-mentioned effect becomes more prominent. It is important to properly select the number of the first internal electrodes 121 (or the second internal electrodes 122) to be stacked in consideration of this.

On the other hand, it is preferable that the interval t between the first internal electrodes 121 (or the second internal electrodes 122) sequentially stacked is 1 to 50 μm. If the interval t is too small, a short phenomenon may occur between the electrodes, and if the interval t is too large, it is difficult to miniaturize the multilayer capacitor. Therefore, the value of the interval t is an appropriate value within the above range. To have.

However, the numerical range is intended to limit the optimal value to implement the effect of the present invention while avoiding a short circuit between the electrodes, even if the interval (t) slightly outside the numerical range may be acceptable if the purpose of the present invention. It is self-evident.

The foregoing detailed description illustrates the present invention. In addition, the foregoing description merely shows and describes preferred embodiments of the present invention, and the present invention can be used in various other combinations, modifications, and environments. That is, changes or modifications may be made within the scope of the concept of the invention disclosed in this specification, the scope equivalent to the disclosed contents, and / or the skill or knowledge in the art. The above-described embodiments are for explaining the best state in carrying out the present invention, the use of other inventions such as the present invention in other state known in the art, and the specific fields of application and uses of the present invention. Various changes are also possible. Accordingly, the detailed description of the invention is not intended to limit the invention to the disclosed embodiments. Also, the appended claims should be construed to include other embodiments.

100: multilayer capacitor according to the present invention
110: ceramic body
121: first internal electrode
122: second internal electrode
123: third internal electrode
130: external terminal

Claims (5)

A multilayer capacitor comprising a ceramic body having a plurality of internal electrodes stacked therein and a pair of external terminals provided at both sides of the ceramic body,
A first internal electrode whose one end is connected to either external terminal;
A second internal electrode disposed to face the first internal electrode at a predetermined interval and having one end connected to the other external terminal; And
A third internal electrode disposed between the first internal electrode and the second internal electrode of the upper and lower layers, wherein at least two or more sheets are successively stacked, and including at least one selected from nickel (Ni) and copper (Cu); ;
Including,
The first and second internal electrodes are stacked in succession of at least two sheets,
The multilayer capacitor having a thickness (t) between the first internal electrode or the second internal electrode stacked in succession is 1 to 50 μm. delete delete delete delete

Images