JP4906990B2 - Through-type multilayer ceramic capacitors for three-dimensional mounting - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is a low ESL and low ESR capacitor suitable for mounting on an electronic device such as a personal computer that has a high operating frequency, and is capable of three-dimensional multilayer printing by keeping the height direction low from the downsizing of the electronic device. The present invention relates to a feedthrough multilayer ceramic capacitor for three-dimensional mounting suitable for surface mounting on a substrate or the like.
[0002]
[Prior art]
In general, in electronic devices such as personal computers, the operating frequency has been increased from 500 MHz to 1 GHz, and a multilayer ceramic capacitor with low ESL and low ESR is required for its power supply circuit. In addition, there has been a demand for a multilayer ceramic capacitor that can be mounted on a three-dimensional printed circuit board or the like with a reduced height in an electronic device, and that can be reliably surface-mounted and have predetermined characteristics.
[0003]
Conventionally, in a through-type multilayer ceramic capacitor, as shown in FIG. 5, a plurality of alternating electrodes having two different electrode patterns positioned in a direction crossing the ceramic layer 11 as the internal electrodes 10... 10a, 10b. There is known a structure in which a laminated chip body is formed in a component body (Japanese Patent Publication No. 62-35257).
[0004]
Among the internal electrodes, one is an inner side of the ceramic layer 11 and one internal electrode 10 extending between the two sides, and the other is a ceramic layer in a direction perpendicular to the single internal electrode 10. Are formed as at least two parallel internal electrodes 10a, 10b... Extending between the other sides.
[0005]
Depending on the laminated chip body, as shown in FIG. 6, external electrodes 12a, 12b, 13a, 13b that are electrically conductive at portions exposed to the laminated surface of the internal electrodes 10, 10a, 10b,. ... (only one side is shown) is provided on the side end face of the multilayer chip body to constitute a through-type multilayer ceramic capacitor.
[0006]
In the multilayer ceramic capacitor, the external electrodes 12a, 12b, 13a, 13b... Are positioned in an upright direction from the plate surface of the circuit board 14, and the entire component is placed on the plate surface of the circuit board 15, and the external electrodes 12a, 12a, The surface mounting is performed by joining and fixing the side surfaces of 12b, 13a, 13b... And the land portions of the circuit patterns 15a, 15b, 16a, 16b.
[0007]
When the multilayer ceramic capacitor is formed of a rectangular ceramic layer, any of the internal electrodes facing each other extends elongated between the short sides of the ceramic layer, and the distance between the external electrodes increases to increase the inductance component. . At the same time, since the distance between the external electrodes is long, the circuit pattern formed on the circuit board becomes long, and the routing of the land portion becomes long, affecting the inductance component.
[0008]
In particular, when surface-mounted on a three-dimensional multilayer printed circuit board, etc., the circuit pattern composed of the land portion at the upper position and the land portion at the lower position becomes longer, and the routing of the land portion becomes longer, affecting the inductance component. The generation of noise is inevitable. Further, when the ESL is lowered and, for example, mounted on the surface in the vicinity of a terminal such as a semiconductor, the influence of the inductance component due to the routing of the land portion when mounted on a three-dimensional printed circuit board cannot be ignored.
[0009]
In addition, since the height direction of the entire component corresponds to the stacking direction of each layer, the height direction of the entire component cannot be kept low depending on the number of layers in each layer. Not suitable as.
[0010]
[Problems to be solved by the invention]
The present invention is suitable for mounting on an electronic device in which the operating frequency of a personal computer or the like is increased as a low ESL and low ESR capacitor by narrowing the interval between the external electrodes. It is an object of the present invention to provide a three-dimensional mounting through-type multilayer ceramic capacitor suitable for surface mounting on a three-dimensional multilayer printed circuit board or the like while keeping the height direction low.
[0011]
[Means for Solving the Problems]
In the through-type multilayer ceramic capacitor for three-dimensional mounting according to the present invention, the first internal electrode extending over both long sides in the middle portion excluding the short sides of the ceramic layer via the ceramic layer, and the in-plane of the ceramic layer Forming a laminated chip body by alternately laminating the second internal electrodes having two lead portions extending from the main portion located on the short side to each short side,
External electrodes that are electrically connected to the first internal electrodes and the exposed portions of the long sides of the ceramic layer are provided on the upper and lower surfaces of the multilayer chip body, and the second internal electrodes and the lead portions are electrically connected to each other. Conductive external electrodes are provided over the entire circumference of the side end surface of the multilayer chip body,
The short side of the ceramic layer to form the laminated chip element and the height direction suppressing the height direction of the whole parts, with sandwich the entire part between the plate surfaces of the upper and lower opposing circuit board, the entire component 3D mounting through type that embeds the side end face of the circuit board in the height direction on the surface of another circuit board and electrically connects each external electrode directly to the different circuit pattern of each circuit board Has been.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
1 to 4, the through-type multilayer ceramic capacitor for three-dimensional mounting according to the illustrated embodiment includes internal electrodes 1 ₁ , 1 ₂ ... Having a predetermined pattern as shown in FIG. A plurality of rectangular ceramic layers 2 are alternately stacked to form a multilayer chip body, and external electrodes 3 and 4 electrically connected to the internal electrodes 1 ₁ , 1 ₂ ... Of the multilayer chip body are stacked chips. It is configured by being provided on a predetermined surface of the element body.
[0013]
The internal electrodes 1 ₁ , 1 ₂ ... Are formed of a Ni or Ni alloy layer by applying and baking a conductive paste such as Ni on the sheet surface of the ceramic green sheet. Alternatively, a Pd—Ag alloy layer can be formed. The ceramic layers 2 are formed by applying a ceramic paste mainly composed of a barium titanate-based, titanium-based, or zirconic acid-based ceramic material on the film surface of the base film, followed by firing and sintering.
[0014]
As shown in FIG. 2, the internal electrodes 1 ₁ , 1 ₂ ... Are formed as _first internal electrodes 1 ₁ ... On the long sides 2 c and 2 d at the intermediate portion except for the short sides 2 a and 2 b of the ceramic layer 2. And an electrode pattern having two lead portions 1b and 1c extending from the main portion 1a located in the plane of the ceramic layer to the short sides 2a and 2b as the second internal electrodes 1 ₂ . Formed from. The lead portions 1b and 1c of the second internal electrodes 1 ₂ ... May be formed to have the same width as the main portion 1a.
[0015]
A plurality of internal electrodes 1 ₁ , 1 ₂ ... And rectangular ceramic layers 2... Are alternately stacked to form a multilayer chip body, and further, a ceramic layer 2 without internal electrodes is stacked as the outermost protective layer. By doing so, a laminated chip body can be configured.
[0016]
The laminated chip body is used as a component body, and the side corresponding to the short sides 2a and 2b of the ceramic layer 2 is formed in the height direction H of the entire component, and the laminated surface formed by the short sides 2a and 2b of the ceramic layer 2 is disposed on the side. The end surface, the laminated surface formed by the long sides 2c and 2d of the ceramic layer 2 is defined as the upper and lower surfaces, and the first inner electrodes 1 ₁ and the portions exposed along the long sides 2c and 2d of the ceramic layer 2 are electrically connected. Each conductive external electrode 3 (the lower side is hidden in the drawing) is provided on the upper and lower surfaces of the multilayer chip body, and each short side of the ceramic layer 2 from the second internal electrode 1 ₂ . External electrodes 4 (on the drawing, the rear side is hidden) that are electrically connected by the two lead portions 1b and 1c extending to 2a and 2b are provided over the entire circumference of the side end surface of the multilayer chip body.
[0017]
The external electrodes 3 and 4 can be formed by applying a Cu paste and drying to form a base layer, and depositing a Ni and Sn plating layer on the base layer. Each of the external electrodes 3 and 4 is configured as a three-dimensional mounting through-type multilayer ceramic capacitor that directly faces and electrically joins different circuit patterns on the circuit board.
[0018]
Of the external electrodes 3 and 4, the external electrode 3 electrically connected to the first internal electrodes 1 ₁ ... Is formed on the entire laminated surface of the laminated chip body formed by the long sides 2 c and 2 d of the ceramic layers 2. Can be formed. Further, since the width of the external electrode 3 is set according to the land shape of the multilayer substrate, the external electrode 3 is at least 50% or more on the laminated surface of the laminated chip body formed by the long sides 2c and 2d of the ceramic layers 2. It can also be formed by keeping the area.
[0019]
As a specific example, the dimensions of the entire part can be configured to be 0.5 ± 0.1 mm in height, 0.8 ± 0.1 mm in width, and 1.6 ± 0.1 mm in length. The ceramic layer has a thickness of 4 μm and can be formed in a shape having a short side of 0.5 ± 0.1 mm and a long side of 0.8 ± 0.1 mm. The distance between the external electrode 3 and the opposing external electrode can be set to a length corresponding to the short side of the ceramic layer.
[0020]
The through-type multilayer ceramic capacitor C configured as described above can be assembled and mounted so as to be sandwiched between the upper and lower opposed circuit boards 5 and 6 in the power supply circuit including the semiconductor device D as shown in FIG. In the three-dimensional mounting, the upper and lower external electrodes 3 and 3 ′ are directly opposed to different circuit patterns 7 a and 7 b on the circuit boards 5 and 6, and the external terminals 4 over the entire circumference of the side end surface are separated. The circuit patterns 8a and 8b provided on the circuit board can be directly faced to each other and electrically joined as + pole / -pole (GND). In this three-dimensional mounting, the height direction H of the entire component can be kept low, and the relative distance between the circuit boards 5 and 6 can be kept small, so that the influence of the inductance component due to the long routing of the land portion can be reduced.
[0021]
In order to reduce the inductance of the circuit pattern, a multilayer ceramic capacitor C having an ESL value of 10 to 20 pH and an ESR value of 5 to 7 mΩ is embedded in the plate surface of a circuit board (not shown). Can be ignored. As a result, when the ESL and ESR of the multilayer ceramic capacitor having the capacitance value of 0.22 μF according to the conventional example and the multilayer ceramic capacitor according to the present invention (the same capacitance value as the conventional example) are compared, When the multilayer ceramic capacitor is 100%, the multilayer ceramic capacitor according to the present invention can be as low as 2-3%.
[0022]
In the through-type multilayer ceramic capacitor according to the present invention, the interval between the external electrodes 3 and 4 is short, the height direction of the entire component can be kept low, and the external electrodes 3 and 4 are wide and easy to be surface-mounted. Even if it is mounted on the substrate, the total inductance due to the routing of the land portion can be reduced, and the land formed on the multilayer substrate can be simplified.
[0023]
【Effect of the invention】
As mentioned above, according to the three-dimensional mounting feedthrough multilayer ceramic capacitor according to the present invention, suppressing the height of the entire component to the short side of the ceramic layer to form a laminated chip element height direction The entire component is sandwiched between the upper and lower opposing circuit board plates , and the side end surfaces of the entire component are embedded in the plate surface of another circuit board in the height direction, and each external electrode has a different circuit pattern on each circuit board. By constructing as a three-dimensional mounting through type that directly faces each other and electrically joins, the distance between external electrodes can be shortened and the height direction of the entire component can be kept low. The total inductance due to the routing of the land can be reduced, the land formed on the multilayer substrate can be simplified, and the operating frequency of a personal computer or the like is increased as a low ESL and low ESR capacitor. Suitable electronics mounting, can be configured as suitable for surface mounting to suppress the reduction in size of electronic devices in the height direction of the entire component low three-dimensional multilayer printed circuit board or the like.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a three-dimensional mounting through-type multilayer ceramic capacitor according to the present invention in a transparent state of an internal structure.
FIG. 2 is an explanatory diagram showing a pattern shape of internal electrodes constituting the three-dimensional mounting through-type multilayer ceramic capacitor according to the present invention.
FIG. 3 is a perspective view showing an appearance including external electrodes of a three-dimensional mounting through-type multilayer ceramic capacitor according to the present invention.
FIG. 4 is an explanatory diagram showing a sandwich mounting structure in a multilayer substrate of a three-dimensional mounting through-type multilayer ceramic capacitor according to the present invention.
FIG. 5 is an explanatory view showing a pattern shape of internal electrodes constituting a through-type multilayer ceramic capacitor according to a conventional example.
FIG. 6 is an explanatory view showing a mounting structure of a three-dimensional mounting through-type multilayer ceramic capacitor according to a conventional example.
[Explanation of symbols]
C Three-dimensional mounting through-type multilayer ceramic capacitor 1 ₁ ... 1st internal electrode 1 ₂ ... 2nd internal electrode 1a Main part 1b of 2nd internal electrode, 1c Lead part 2 of 2nd internal electrode ... Ceramic layer 2a, 2b Ceramic layer short side 2c, 2d Ceramic layer long side 3, 4 External electrode 5, 6 Circuit boards 7a, 7b, 8a, 8b Circuit pattern H Height direction of entire component

Claims (1)

A plurality of internal electrodes of a predetermined pattern and rectangular ceramic layers are alternately stacked to form a multilayer chip body, and external electrodes that are electrically connected to the internal electrodes of the multilayer chip body are connected to a predetermined surface of the multilayer chip body. In the through-type multilayer ceramic capacitor for three-dimensional mounting provided in
A first internal electrode extending over both long sides at the intermediate portion excluding the short sides of the ceramic layer through the ceramic layer, and two lead portions extending from the main portion located in the plane of the ceramic layer to the short sides. A laminated chip body is formed by alternately laminating second internal electrodes having
External electrodes that are electrically connected to the first internal electrodes and the exposed portions of the long sides of the ceramic layer are provided on the upper and lower surfaces of the multilayer chip body, and the second internal electrodes and the lead portions are electrically connected to each other. Conductive external electrodes are provided over the entire circumference of the side end surface of the multilayer chip body,
The short side of the ceramic layer to form the laminated chip element and the height direction suppressing the height direction of the whole parts, with sandwiching the entire part between the plate surfaces of the upper and lower opposing circuit board, the entire part of the The side end face is embedded in the board surface of another circuit board in the height direction, and each external electrode is configured as a through-type for three-dimensional mounting in which each circuit board directly faces each other and is electrically connected to each other. A three-dimensional through-type multilayer ceramic capacitor for mounting.

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