Electronic component and substrate module including an embedded capacitor

In an electronic component and a substrate module, a laminated body includes a first capacitor conductor and a second capacitor conductor embedded therein, which define a capacitor. First and second external electrodes are connected to the first capacitor conductor and the second capacitor conductor through extraction conductors, respectively. Third and fourth external electrodes are connected to the first capacitor conductor through extraction conductors. Fifth and sixth external electrodes are connected to the second capacitor conductor through extraction conductors. On a first side surface, no external electrode having an electrical potential different from the electrical potential of the third external electrode is provided between a first end surface and the third external electrode. On the first side surface, no external electrode having an electrical potential different from the electrical potential of the fifth external electrode is provided between a second end surface and the fifth external electrode.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an electronic component and a substrate module, and more specifically, to an electronic component and a substrate module each of which includes a capacitor embedded therein.

2. Description of the Related Art

For example, as an electronic component of the related art, a known multilayer capacitor is described in Japanese Unexamined Patent Application Publication No. 2004-140183.FIG. 18is the front view of a multilayer capacitor500described in Japanese Unexamined Patent Application Publication No. 2004-140183.

The multilayer capacitor500includes a laminated body502, internal conductors504and506, extraction electrodes508and510, and external electrodes512and514. The laminated body502is configured by laminating a plurality of dielectric layers. InFIG. 18, a surface on the underside of the laminated body502is a mounting surface. The internal conductors504and506are laminated along with a dielectric layer, and face each other across the dielectric layer, thereby forming electrostatic capacity. The extraction electrodes508and510are connected to the internal conductors504and506, respectively, and are extracted to the mounting surface. The external electrodes512and514are connected to the extraction electrodes508and510, respectively. In the multilayer capacitor500described above, by maintaining a distance between the extraction electrodes508and510and a distance from the internal conductors504and506to the mounting surface in a predetermined relationship, a reduction of the equivalent series inductance is achieved.

However, in the multilayer capacitor500described in Japanese Unexamined Patent Application Publication No. 2004-140183, since the external electrodes512and514are adjacent to each other, the external electrode512and the external electrode514may be connected to each other by solder when the multilayer capacitor500is mounted on a circuit substrate. Namely, in the multilayer capacitor500, a short circuit may occur.

SUMMARY OF THE INVENTION

To overcome the problems described above, preferred embodiments of the present invention provide an electronic component and a substrate module in which low ESL properties are achieved while a short circuit is prevented from occurring when the electronic component and the substrate module are mounted on a circuit substrate.

An electronic component according to a preferred embodiment of the present invention preferably includes a substantially rectangular parallelepiped-shaped laminated body in which a plurality of dielectric layers are laminated, a first capacitor conductor provided on a dielectric layer, a first extraction conductor connected to the first capacitor conductor and extending to a first end surface of the laminated body, a third extraction conductor connected to the first capacitor conductor and extending to a first side surface of the laminated body, a second capacitor conductor provided on the dielectric layer and facing the first capacitor conductor across the dielectric layer, a second extraction conductor connected to the second capacitor conductor and extending to a second end surface of the laminated body, a fourth extraction conductor connected to the second capacitor conductor and extending to the first side surface, a first external electrode and a second external electrode arranged so as to extend to the first end surface and the second end surface, respectively, and to a bottom surface of the laminated body and connected to the first extraction conductor and the second extraction conductor, respectively, a third external electrode provided on the first side surface and connected to the third extraction conductor, and a fourth external electrode provided on the first side surface and connected to the fourth extraction conductor, wherein no external electrode maintained at an electrical potential different from an electrical potential of the third external electrode is provided between the first end surface and the third external electrode, on the first side surface, and no external electrode maintained at an electrical potential different from an electrical potential of the fourth external electrode is provided between the second end surface and the fourth external electrode, on the first side surface.

A substrate module according to a preferred embodiment of the present invention preferably includes a circuit substrate including a first land and a second land, and the electronic component to be mounted in the circuit substrate, wherein the first external electrode is connected to the first land, and the second external electrode is connected to the second land.

According to various preferred embodiments of the present invention, low ESL properties of an electronic component and a substrate module are achieved and a short circuit is prevented from occurring when the electronic component and the substrate module are mounted on a circuit substrate.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, electronic components and substrate modules according to preferred embodiments of the present invention will be described with reference to drawings.

First Preferred Embodiment

First, the configuration of an electronic component according to a first preferred embodiment of the present invention will be described with reference to drawings.FIG. 1is an external perspective view of an electronic component10according to the first preferred embodiment.FIG. 2is the exploded perspective view of a laminated body11of the electronic component10inFIG. 1.FIGS. 3A and 3Bare the internal plan views of the electronic component inFIG. 1. Hereinafter, the lamination direction of the laminated body11is defined as a z-axis direction. When the plan view of the laminated body11is viewed from the z-axis direction, a direction in which the long side of the laminated body11extends is defined as an x-axis direction. When the plan view of the laminated body11is viewed from the z-axis direction, a direction in which the short side of the laminated body11extends is defined as a y-axis direction.

For example, the electronic component10is preferably a chip capacitor used as a coupling capacitor, and, as illustrated inFIG. 1toFIG. 3B, includes the laminated body11, external electrodes12(12a,12b) and13to16, and internal conductors30(30ato30c) and31(31ato31c) (not illustrated inFIG. 1).

The laminated body11preferably has a substantially rectangular parallelepiped shape, for example. However, the laminated body11is preferably chamfered, and thus substantially has a shape in which the corners and the ridge lines thereof are rounded. Hereinafter, in the laminated body11, a surface on a positive direction side in the z-axis direction is referred to as a top surface S1and a surface on a negative direction side in the z-axis direction is a bottom surface S2. In addition, a surface on a negative direction side in the x-axis direction is referred to as an end surface S3and a surface on a positive direction side in the x-axis direction is referred to as an end surface S4. In addition, a surface on a positive direction side in the y-axis direction is it is assumed that a side surface S5and a surface on a negative direction side in the y-axis direction is it is assumed that a side surface S6.

As illustrated inFIG. 2, a plurality of ceramic layers17(17ato17h) are laminated from the positive direction side to the negative direction side in the z-axis direction so as to be arranged in this order, and thus the laminated body11is configured. The ceramic layer17preferably has a substantially rectangle shape, for example, and is manufactured using dielectric ceramic. Hereinafter, a main surface on the positive direction side in the z-axis direction of the ceramic layer17is referred to as a front surface and a main surface on the negative direction side in the z-axis direction of the ceramic layer17is referred to as a back surface.

The top surface S1of the laminated body11is defined by the front surface of the ceramic layer17aprovided on the farthest positive direction side in the z-axis direction. The bottom surface S2of the laminated body11is defined by the back surface of the ceramic layer17hprovided on the farthest negative direction side in the z-axis direction. In addition, the short sides of the ceramic layers17ato17hon the negative direction side in the x-axis direction are aligned or substantially aligned, and thus the end surface S3is configured. The short sides of the ceramic layers17ato17hon the positive direction side in the x-axis direction are aligned or substantially aligned, and thus the end surface S4is configured. The long sides of the ceramic layers17ato17hon the positive direction side in the y-axis direction are lined, and hence the side surface S5is configured. The long sides of the ceramic layers17ato17hon the negative direction side in the y-axis direction are aligned or substantially aligned, and thus the side surface S6is configured.

As illustrated inFIG. 2andFIGS. 3A and 3B, the internal conductors30ato30care provided on the front surfaces of the ceramic layers17b,17d, and17f, respectively, and are embedded in the laminated body11. The internal conductors31ato31care provided on the front surfaces of the ceramic layers17c,17e, and17g, respectively, and are embedded in the laminated body11. Particularly, the internal conductor30and the internal conductor31are alternately laminated in the z-axis direction.

The internal conductor30(30ato30c) preferably includes a capacitor conductor18(18ato18c) and extraction conductors20(20ato20c),22(22ato22c), and23(23ato23c). The capacitor conductor18preferably has a substantially rectangle shape, for example, and is provided on the front surface of the ceramic layer17so as not to be in contact with the outer edge of the ceramic layer17.

The extraction conductor20is connected to the capacitor conductor18and extends to the end surface S3of the laminated body11, thereby being exposed from the end surface S3. More specifically, the extraction conductor20extends from the short side on the negative direction side in the x-axis direction of the capacitor conductor18toward the negative direction side in the x-axis direction. Accordingly, the extraction conductor20extends to the short side on the negative direction side in the x-axis direction of the ceramic layer17.

The extraction conductor22is connected to the capacitor conductor18and extends to the side surface S5of the laminated body11, thereby being exposed from the side surface S5. More specifically, the extraction conductor22extends from a position, located on the negative direction side in the x-axis direction from the midpoint of the long side on the positive direction side in the y-axis direction of the capacitor conductor18, toward the positive direction side in the y-axis direction. Accordingly, the extraction conductor22extends to a position, located on the negative direction side in the x-axis direction from the midpoint of the long side on the positive direction side in the y-axis direction of the ceramic layer17.

The extraction conductor23is connected to the capacitor conductor18and extends to the side surface S6of the laminated body11, thereby being exposed from the side surface S6. More specifically, the extraction conductor23extends from a position, located on the negative direction side in the x-axis direction from the midpoint of the long side on the negative direction side in the y-axis direction of the capacitor conductor18, toward the negative direction side in the y-axis direction. Accordingly, the extraction conductor23extends to a position, located on the negative direction side in the x-axis direction from the midpoint of the long side on the negative direction side in the y-axis direction of the ceramic layer17.

The internal conductor31(31ato31c) includes a capacitor conductor19(19ato19c) and extraction conductors21(21ato21c),24(24ato24c), and25(25ato25c). The capacitor conductor19preferably has a substantially rectangle shape, for example, and is provided on the front surface of the ceramic layer17so as not to be in contact with the outer edge of the ceramic layer17. In addition, the capacitor conductor19faces the capacitor conductor18across the ceramic layer17. Accordingly, electrostatic capacity, i.e., a capacitor, is provided between the capacitor conductors18and19.

The extraction conductor21is connected to the capacitor conductor19and extends to the end surface S4of the laminated body11, thereby being exposed from the end surface S4. More specifically, the extraction conductor21extends from the short side on the positive direction side in the x-axis direction of the capacitor conductor19toward the positive direction side in the x-axis direction. Accordingly, the extraction conductor21extends to the short side on the positive direction side in the x-axis direction of the ceramic layer17.

The extraction conductor24is connected to the capacitor conductor19and extends to the side surface S5of the laminated body11, thereby being exposed from the side surface S5. More specifically, the extraction conductor24extends from a position, located on the positive direction side in the x-axis direction from the midpoint of the long side on the positive direction side in the y-axis direction of the capacitor conductor19, toward the positive direction side in the y-axis direction. Accordingly, the extraction conductor24extends to a position, located on the positive direction side in the x-axis direction from the midpoint of the long side on the positive direction side in the y-axis direction of the ceramic layer17. Compared with the extraction conductor22, the extraction conductor24is located on the positive direction side in the x-axis direction when the plan view of the extraction conductor24is viewed from the z-axis direction.

The extraction conductor25is connected to the capacitor conductor19and extends to the side surface S6of the laminated body11, thereby being exposed from the side surface S6. More specifically, the extraction conductor25extends from a position, located on the positive direction side in the x-axis direction from the midpoint of the long side on the negative direction side in the y-axis direction of the capacitor conductor19, toward the negative direction side in the y-axis direction. Accordingly, the extraction conductor25extends to a position, located on the positive direction side in the x-axis direction from the midpoint of the long side on the negative direction side in the y-axis direction of the ceramic layer17. Compared with the extraction conductor23, the extraction conductor25is located on the positive direction side in the x-axis direction when the plan view of the extraction conductor25is viewed from the z-axis direction.

The external electrodes12aand12bare arranged so as to extend to the end surfaces S3and S4, respectively, and to the top surface S1, the bottom surface S2, and the side surfaces S5and S6of the laminated body11, and are connected to the extraction conductors20ato20cand the extraction conductors21ato21c, respectively. More specifically, the external electrode12apreferably substantially covers the whole surface of the end surface S3of the laminated body11so as to cover a portion at which the extraction conductors20ato20care exposed from the end surface S3. Furthermore, the external electrode12ais arranged to extend from the end surface S3to the top surface S1, the bottom surface S2, and the side surfaces S5and S6. The external electrode12bpreferably substantially covers the entire surface of the end surface S4of the laminated body11so as to cover a portion at which the extraction conductors21ato21care exposed from the end surface S4. Furthermore, the external electrode12bis arranged to extend from the end surface S4to the top surface S1, the bottom surface S2, and the side surfaces S5and S6.

The external electrodes13and14are provided on the side surfaces S5and S6, respectively, and connected to the extraction conductors22ato22cand the extraction conductors23ato23c, respectively. More specifically, the external electrode13preferably has a substantially band shape extending in the z-axis direction on the side surface S5of the laminated body11so as to cover a portion at which the extraction conductors22ato22care exposed from the side surface S5. Furthermore, the external electrode13is arranged to extend from the side surface S5to the top surface S1and the bottom surface S2. The external electrode14preferably has a substantially band shape extending in the z-axis direction on the side surface S6of the laminated body11so as to cover a portion at which the extraction conductors23ato23care exposed from the side surface S6. The external electrode14faces the external electrode13. Furthermore, the external electrode14is arranged to extend from the side surface S6to the top surface S1and the bottom surface S2.

The external electrodes15and16are provided on the side surfaces S5and S6, respectively, and connected to the extraction conductors24ato24cand the extraction conductors25ato25c, respectively. More specifically, the external electrode15preferably has a substantially band shape extending in the z-axis direction on the side surface S5of the laminated body11so as to cover a portion where the extraction conductors24ato24care exposed from the side surface S5. Furthermore, the external electrode15is arranged to extend from the side surface S5to the top surface S1and the bottom surface S2. In addition, since, as compared to the extraction conductor22, the extraction conductor24is located on the positive direction side in the x-axis direction, the external electrode15is located on the positive direction side in the x-axis direction as compared to the external electrode13. The external electrode16preferably has a substantially band shape extending in the z-axis direction on the side surface S6of the laminated body11so as to cover a portion at which the extraction conductors25ato25care exposed from the side surface S6. The external electrode16faces the external electrode15. Furthermore, the external electrode16is arranged to extend from the side surface S6to the top surface S1and the bottom surface S2. In addition, since, as compared to the extraction conductor23, the extraction conductor25is located on the positive direction side in the x-axis direction, the external electrode16is located on the positive direction side in the x-axis direction compared with the external electrode14.

In addition, as illustrated inFIG. 1, in the electronic component10, preferably, no external electrodes that have electrical potentials different from those of the external electrodes13and14are provided between the end surface S3and the external electrodes13and14on the side surfaces S5and S6, respectively. In addition, as illustrated inFIG. 1, the external electrode12ais arranged to extend from the end surface S3to the side surfaces S5and S6. Therefore, the external electrode12ais individually provided between the end surface S3and the external electrodes13and14. However, the external electrode12ais individually electrically connected to the external electrodes13and14through the internal conductor30. Therefore, the electrical potential of the external electrode12ais equal to the electrical potentials of the external electrodes13and14.

In addition, as illustrated inFIG. 1, in the electronic component10, no external electrodes having electrical potentials different from those of the external electrodes15and are provided between the end surface S4and the external electrodes15and16on the side surfaces S5and S6, respectively. In addition, as illustrated inFIG. 1, the external electrode12bis arranged to extend from the end surface S4to the side surfaces S5and S6. Therefore, the external electrode12bis individually provided between the end surface S4and the external electrodes15and16. However, the external electrode12bis individually electrically connected to the external electrodes15and16through the internal conductor31. Therefore, the electrical potential of the external electrode12bis equal to the electrical potentials of the external electrodes15and16.

Furthermore, no external electrode having an electrical potential different from those of the external electrodes13and15is provided between the external electrode13and the external electrode15on the side surface S5. In the same manner, no external electrode having an electrical potential different from those of the external electrodes14and16is provided between the external electrode14and the external electrode16on the side surface S6. Particularly, no external electrode is provided between the external electrodes13and15and between the external electrodes14and16. Accordingly, the external electrodes13and15are adjacent to each other, and the external electrodes14and16are adjacent to each other.

Next, a manufacturing method for the electronic component10will be described.

First, BaTiO3, CaTiO3, SrTiO3, or CaZrO3as a main component and Mn compound, Fe compound, Cr compound, Co compound, Ni compound, or rare earth compound as an accessory component, for example, are weighed with a predetermined ratio and put in a ball mill and wet blended. After the blended material is dried and ground to form a powder, and the powder is calcined. After the calcined powder has been wet-ground using a ball mill, the calcined powder is dried and then cracked, thereby obtaining dielectric ceramic powder.

Organic binder and organic solvent are added to this dielectric ceramic powder to be mixed using a ball mill to form a ceramic slurry. The ceramic slurry is formed in a substantially sheet shape on a carrier sheet by a doctor blade method, for example, and dried, and a ceramic green sheet to be the ceramic layer17is manufactured. It is preferable that the thickness of the ceramic green sheet to be the ceramic layer17is in the range of about 0.5 μm to about 10 μm, for example.

Next, by applying paste including conductive material on the ceramic green sheet to be the ceramic layer17by a method such as a screen printing method, a photolithographic method, or other suitable method, for example, the internal conductors30and31are formed. For example, the paste including conductive material is obtained by adding organic binder and organic solvent to metal powder. For example, the metal powder is Ni, Cu, Ag, Pd, Ag—Pd alloy, Au, or other suitable metal powder. It is preferable that the thicknesses of the internal conductors30and31are in the range of about 0.3 μm to about 2.0 μm, for example.

Next, by laminating the ceramic green sheet to be the ceramic layer17, an unfired mother laminated body is obtained. Thereafter, the unfired mother laminated body is subjected to pressure bonding using an isostatic press, for example.

Next, the unfired mother laminated body is cut to a predetermined size, and a plurality of unfired laminated bodies11are obtained. After that, the front surface of the laminated body11is subjected to a polishing process, such as barrel polishing or other suitable polishing process, for example.

Next, the unfired laminated body11is fired. For example, it is preferable that a firing temperature is in the range of about 900° C. to about 1300° C. According to the process described above, the preparation of the laminated body11is completed.

Next, the external electrodes12to16are formed on the laminated body11. Specifically, conductive paste is applied to the front surface of the laminated body11by a dip method or a slit method of the related art or other suitable method, for example. In addition, by baking the conductive paste at a temperature in the range of about 700° C. to about 900° C., the underlying electrodes of the external electrodes12to16are formed. For example, as the material of the conductive paste, Cu, Ni, Ag, Pd, Ag—Pd alloy, Au, or other suitable material may be used. It is preferable that the thickness of the underlying electrode is in the range of about 10 μm to about 50 μm. Next, plating is applied on the underlying electrodes, and the external electrodes12to16are completed. For example, as the material of a plated layer, Cu, Ni, Ag, Pd, Ag—Pd alloy, Au, or other suitable material may be used. In addition, by performing plating more than once, a plurality of plated layers may be formed on the underlying electrode. According to the process described above, the preparation of the electronic component10is completed.

Next, a substrate module40aincluding the electronic component10will be described with reference to drawings.FIG. 4Ais the cross-sectional structural view of the substrate module40aandFIG. 4Bis a plan view of the substrate module40aviewed from a positive direction side in a z-axis direction.FIG. 5is the equivalent circuit diagram of the substrate module40ainFIGS. 4A and 4B.

As illustrated inFIG. 4A, the substrate module40aincludes the electronic component10and a circuit substrate51. The circuit substrate51preferably includes a substrate main body52, a signal conductor54, a ground electrode55, a via hole conductor56, and a ground conductor G.

The substrate main body52is a laminated substrate in which a plurality of ceramic layers and a plurality of conductor layers are laminated, and includes electrical circuits on the main surface and inside the substrate main body. The signal conductor54is provided on a main surface in the positive direction side in the z-axis direction of the substrate main body52, and extends in a y-axis direction as illustrated inFIG. 4B. An input port P1(not illustrated) is provided on an end portion on a positive direction side in the y-axis direction of the signal conductor54, and an output port P2(not illustrated) is provided on an end portion on a negative direction side in the y-axis direction of the signal conductor54. The ground electrode55is provided on a main surface in the positive direction side in the z-axis direction of the circuit substrate51, and has a substantially rectangle shape as illustrated inFIG. 4B.

The ground conductor G is provided within the substrate main body52, and is maintained at a ground potential. The ground conductor G is connected to a ground port P3(not illustrated). The via hole conductor56is provided within the substrate main body52, and connects the ground electrode55and the ground conductor G to each other. Accordingly, the ground electrode55is also maintained at the ground potential.

The electronic component10is mounted in the circuit substrate51. More specifically, the external electrode12ais connected to the signal conductor54by solder60a. In addition, the external electrode12bis connected to the ground electrode55by solder60b. Accordingly, the substrate module40ahas a circuit configuration as illustrated inFIG. 5. Particularly, the signal conductor54connects the input port P1and the output port P2to each other. In addition, the electronic component10is provided between the signal conductor54and the ground port P3. InFIG. 5, a capacitor C, a resistance R, and a coil L indicate an electrostatic capacity, an electrical resistance, and an inductor included in the electronic component10. The substrate module40ais preferably configured as illustrated inFIG. 5, and thus a high-frequency signal is input from the input port P1and output from the output port P2. Furthermore, a high-frequency signal corresponding to the resonance frequency of the electronic component10, from among the high-frequency signal input from the input port P1, is not output from the output port P2but is output from the ground port P3. In addition, the circuit configuration of the substrate module40ais not limited toFIG. 5. Accordingly, in the substrate module40a, the electronic component10may be provided between the input port P1and the output port P2.

According to the electronic component10and the substrate module40adescribed above, a low ESL property is obtained as described below.FIG. 6is the external perspective view of an electronic component110according to a comparative example.FIG. 7is the exploded perspective view of a laminated body111of the electronic component110according to the comparative example. The electronic component110according to the comparative example is obtained by removing the extraction conductors22to25and the external electrodes13to16from the electronic component10according to the first preferred embodiment. Therefore, in the electronic component110, a reference symbol obtained by adding “100” to the reference symbol in the electronic component10is assigned to the same elements as the electronic component10.

In the electronic component110illustrated inFIG. 7, a laminated body111includes ceramic layers117ato117h. The internal conductors130ato130care provided on the front surfaces of the ceramic layers117b,117d, and117f, respectively, and are embedded in the laminated body111. The internal conductors131ato131care provided on the front surfaces of the ceramic layers117c,117e, and117g, respectively, and are embedded in the laminated body111. In a substrate module in which the electronic component110according to the comparative example is mounted, a high-frequency signal is input from the signal conductor into the electronic component110through the external electrode112a, and output to the ground electrode through the external electrode112b. At this time, the high-frequency signal flows through the signal conductor, the external electrode112a, the extraction conductors120ato120c, the capacitor conductors118ato118c, the capacitor conductors119ato119c, the extraction conductors121ato121c, the external electrode112b, and the ground electrode in this order. Particularly, in the substrate module in which the electronic component110according to the comparative example is mounted, the high-frequency signal only flows through one path. On the other hand, in the electronic component10according to the first preferred embodiment in the substrate module40a, a high-frequency signal is input from the signal conductor54into the electronic component10through the external electrode12a, and output to the ground electrode55through the external electrode12b. At this time, the high-frequency signal flows through a first path and a second path as described below.

The first path is a path in which the high-frequency signal flows through the signal conductor54, the external electrode12a, the extraction conductor20, the capacitor conductor18, the capacitor conductor19, the extraction conductor21, the external electrode12b, and the ground electrode55in this order. The second path is a path in which the high-frequency signal flows through the signal conductor54, the external electrode12a, the extraction conductor20, the capacitor conductor18, the extraction conductors22and23, the external electrodes13and14, the external electrodes15and16, the extraction conductors24and25, the capacitor conductors19, the extraction conductor21, the external electrode12b, and the ground electrode55in this order. In the second path, when the high-frequency signal flows from the external electrodes13and14to the external electrodes15and16, the high-frequency signal preferably passes through the inside of a dielectric between the external electrodes13and14and the external electrodes15and16, and thus the high-frequency signal passes from the external electrodes13and14to the external electrodes15and16.

As described above, in the substrate module40ain which the electronic component10is mounted, the high-frequency signal preferably flows through the first path and the second path that are connected in parallel to each other. The first path in the electronic component10is the same or substantially the same as the path in the electronic component110. Accordingly, the electronic component10is preferably configured such that the second path is added to the electronic component110. In addition, the combined impedance value LT of the inductance value L1of the first path and the inductance value L2of the second path is indicated in the following expression (1).
LT=L1·L2/(L1+L2)  (1)

The inductance value of the path in the electronic component110is L1. Accordingly, the combined impedance value LT of the first path and the second path in the electronic component10is less than the inductance value L1of the path in the electronic component110. Particularly, as compared to the electronic component110, the low ESL property of the electronic component10is achieved.

In addition, in the electronic component10, by achieving the low ESL property of the electronic component10, the resonance frequency thereof is increased. As a result, the high-frequency characteristics of the electronic component10are improved.

In addition, it is preferable that no external electrode having an electrical potential different from the electrical potentials of the external electrodes13and15is provided between the external electrodes13and15on the side surface S5so that the high-frequency signal flows from the external electrodes13and14to the external electrodes15and16. In the same manner, it is preferable that no external electrode having an electrical potential different from the electrical potentials of the external electrodes14and16is provided between the external electrodes14and16on the side surface S6.

In addition, it is preferable that a distance between the external electrodes13and14and a distance between the external electrodes15and16are as small as possible, for example, in the range of about 50 μm to about 200 μm, so that the high-frequency signal flows from the external electrodes13and14to the external electrodes15and16.

In addition, in the electronic component10, a short circuit is prevented from occurring when the electronic component10is mounted on the circuit substrate51. More specifically, in the multilayer capacitor500described in Japanese Unexamined Patent Application Publication No. 2004-140183, since the external electrodes512and514are adjacent to each other, the external electrode512and the external electrode514may be connected to each other by solder when the multilayer capacitor500is mounted on a circuit substrate. That is, in the multilayer capacitor500, a short circuit may occur.

On the other hand, as compared to the external electrodes512and514in the multilayer capacitor500described in Japanese Unexamined Patent Application Publication No. 2004-140183, the external electrodes12aand12bare not adjacent to each other in the electronic component10. Instead, the external electrode13and the external electrode15are adjacent to each other. In the same manner, the external electrode14and the external electrode16are adjacent to each other. However, the external electrodes13to16are not solder-mounted in the circuit substrate51. Therefore, it is unlikely that the external electrode13and the external electrode15are solder-connected to each other and the external electrode14and the external electrode16is solder-connected to each other. Accordingly, in the electronic component10, a short circuit is prevented from occurring when the electronic component10is mounted on the circuit substrate51.

In addition, in the electronic component10, it is less likely that a loss occurs in the high-frequency signal flowing through the electronic component10. More specifically, in the electronic component10, it is necessary for the high-frequency signal to flow toward the positive direction side in the x-axis direction. Here, in the electronic component10, when external electrodes having electrical potentials different from those of the external electrodes13and14are provided between the end surface S3and the external electrodes13and14on the side surfaces S5and S6, the high-frequency signals flow from the external electrodes13and14toward the external electrodes (that is, towards the negative direction side in the x-axis direction). Particularly, the high-frequency signals flow in a direction opposite to a direction in which the high-frequency signals are to flow, and thus a loss occurs. Therefore, as illustrated inFIG. 1, in the electronic component10, no external electrodes having electrical potentials different from those of the external electrodes13and14are provided between the end surface S3and the external electrodes13and14on the side surfaces S5and S6, respectively. Accordingly, the loss is prevented from occurring. In addition, for the same or substantially the same reason, no external electrodes having electrical potentials different from those of the external electrodes15and16are provided between the end surface S4and the external electrodes15and16on the side surfaces S5and S6, respectively.

In the electronic component10, it is possible to prevent delamination from occurring. More specifically, in an electronic component, delamination is more likely to occur at the corner of a laminated body. When an extraction electrode and a ceramic layer are laminated at the corner, delamination is more likely to occur between the extraction electrode and the ceramic layer. Therefore, in the electronic component10, the extraction conductors20and21preferably do not extend to the corner of the laminated body11. Accordingly, in the electronic component10, delamination is prevented from occurring. Furthermore, in the electronic component10, since the extraction electrodes20and21are not exposed at the corner of the laminated body11, the moisture resistance of the electronic component10is improved.

In order to clarify the advantageous effects obtained by the electronic component10and the substrate module40a, the inventors of the present invention performed a first experiment described below. Specifically, a sample (hereinafter, the first sample) of the substrate module40aillustrated inFIGS. 4A and 4Band a sample (second sample) of a substrate module in which the electronic component110illustrated inFIG. 6andFIG. 7is mounted in the circuit substrate51inFIGS. 4A and 4Bwere manufactured. In addition, using a network analyzer (Agilent 8722D), the ESLs and the transmission characteristics (S21) of the first sample and the second sample were measured. First, the parameters of the first sample and the second sample will be described.Dimension: about 2.096 mm×about 1.290 mm×about 0.793 mmElectrostatic capacity: about 14 pFMaterial of an internal conductor and an external electrode: CuThe relative dielectric constant (∈) of a ceramic layer: about 27The number of internal conductors: about 6An element thickness (a distance between the internal conductors30and31): about 122 μmOuter layer thickness (a distance from the internal conductors30aand31cto the top surface S1or bottom surface S2of the laminated body11): about 88 μm

In the first sample and the second sample with the above-described parameters, the ESLs thereof are as follows. In addition, the ESLs were measured in a frequency bandwidth of about 0.5 GHz to about 20 GHz.The ESL of the first sample: about 465 pHThe ESL of the second sample: about 500 pH

Accordingly, based on the first experiment, it is understood that, in the substrate module40aincluding the electronic component10, a reduced ESL property is achieved as compared to the circuit module including the electronic component110.

FIG. 8is a graph illustrating the transmission characteristics (S21) of the first sample and the second sample. A vertical axis indicates attenuation, and a horizontal axis indicates a frequency.

According toFIG. 8, it is understood that the self-resonance frequency f1of the first sample is greater than the self-resonance frequency f2of the second sample. Specifically, the self-resonance frequency f1is about 1.975 GHz, and the self-resonance frequency f2is about 1.905 GHz. Accordingly, based on the experimental result inFIG. 8, it is understood that the high-frequency characteristic of the substrate module40ais superior to the high-frequency characteristic of the circuit module including the electronic component110.

First Modification

Next, a substrate module according to a first modification of the first preferred embodiment of the present invention will be described with reference to the drawings.FIG. 9is the cross-section structure diagram of a substrate module40b.

The substrate module40bdiffers from the substrate module40ain that the external electrodes15and16are preferably connected to the ground electrode55by solder60c. Since no other differences exist between the substrate module40band the substrate module40a, further description of the configuration of the substrate module40bis omitted.

In the substrate module40a, the high-frequency signals flow through the first path and the second path. On the other hand, in the substrate module40b, the high-frequency signals preferably flow through a third path and a fourth path described below, in addition to the first path and the second path.

The third path is a path in which the high-frequency signal flows through the signal conductor54, the external electrode12a, the extraction conductor20, the capacitor conductor18, the capacitor conductor19, the extraction conductors24and25, the external electrodes15and16, and the ground electrode55in this order. The fourth path is a path in which the high-frequency signal flows through the signal conductor54, the external electrode12a, the extraction conductor20, the capacitor conductor18, the extraction conductors22and23, the external electrodes13and14, the external electrodes15and16, and the ground electrode55in this order.

As described above, in the substrate module40b, the high-frequency signals preferably also flow through the third path and the fourth path in addition to the first path and the second path. As a result, in the substrate module40b, while the low ESL thereof is achieved as compared to the substrate module40a, the high-frequency characteristics thereof are improved.

In addition, in the substrate module40b, the external electrodes15and16adjacent to the external electrodes13and are preferably connected to the ground electrode55by the solder60c. However, the electronic component10is preferably fixed to the circuit substrate51primarily via a connection between the external electrode12aand the signal conductor54and a connection between the external electrode12band the ground electrode55. Therefore, it is only necessary for the external electrodes15and16to be electrically connected to the ground electrode55, and it is not necessary for the external electrodes15and16to be rigidly fixed to the ground electrode55. Therefore, the quantity of the solder60cmay be relatively small. Accordingly, it is unlikely that the external electrodes13and14will be connected to the external electrodes15and16by the solder60c. Particularly, in the substrate module40b, a short circuit is also prevented from occurring when the electronic component10is mounted on the circuit substrate51.

Second Modification

Next, a substrate module according to a second modification of the second preferred embodiment of the present invention will be described with reference to the drawings.FIG. 10is the cross-sectional view of a substrate module40c.

The substrate module40cdiffers from the substrate module40bin that the external electrodes13and14are preferably connected to the signal conductor54by solder60d. Since no other differences exist, further description of the configuration of the substrate module40cis omitted.

In the substrate module40b, the high-frequency signals flow through from the first path to the fourth path. On the other hand, in the substrate module40c, the high-frequency signals flow through a fifth path to a seventh path described below, in addition to the first path to the fourth path.

The fifth path is a path in which the high-frequency signal preferably flows through the signal conductor54, the external electrodes13and14, the extraction conductors22and23, the capacitor conductor18, the capacitor conductor19, the extraction conductor21, the external electrode12b, and the ground electrode55in this order. The sixth path is a path in which the high-frequency signal preferably flows through the signal conductor54, the external electrodes13and14, the extraction conductors22and23, the capacitor conductor18, the capacitor conductor19, the extraction conductors24and25, the external electrodes15and16, and the ground electrode55in this order. The seventh path is a path in which the high-frequency signal preferably flows through the signal conductor54, the external electrodes13and14, the external electrodes15and16, and the ground electrode55in this order.

As described above, in the substrate module40c, the high-frequency signals also flow through from the fifth path to the seventh path in addition to the first path to the fourth path. As a result, in the substrate module40c, a reduced ESL is achieved as compared to the substrate module40a, and the high-frequency characteristics thereof are improved.

In addition, in the substrate module40c, the external electrodes13and14are connected to the signal conductor54by the solder60d, and the external electrodes15and16are connected to the ground electrode55by the solder60c. However, the electronic component10is preferably fixed to the circuit substrate51primarily via a connection between the external electrode12aand the signal conductor54and a connection between the external electrode12band the ground electrode55. Therefore, it is only necessary for the external electrodes13and14to be electrically connected to the signal conductor54, and it is not necessary for the external electrodes15and16to be rigidly fixed to the signal conductor54. In the same manner, it is only necessary for the external electrodes15and16to be electrically connected to the ground electrode55, and it is not necessary for the external electrodes15and16to be rigidly fixed to the ground electrode55. Therefore, the quantities of the solder60cand the solder60dmay be reduced. Accordingly, it is unlikely that the external electrodes13and14are connected to the external electrodes15and16by the solder60cand the solder60d. Particularly, in the substrate module40c, a short circuit is also prevented from occurring when the electronic component10is mounted on the circuit substrate51.

In order to clarify the advantageous effects obtained by the electronic component10and the substrate modules40band40c, the inventors of the present invention performed a second experiment described below. Specifically, a sample (hereinafter, the third sample) of the substrate module40billustrated inFIG. 9and a sample (hereinafter, the fourth sample) of the substrate module40cillustrated inFIG. 10were manufactured. In addition, the ESLs and the transmission characteristics (S21) of the third sample and the fourth sample were measured. Since the parameters of the third sample and the fourth sample are the same as the parameters of the first sample and the second sample, the descriptions thereof are omitted.

In the third sample and the fourth sample, the ESLs thereof are as follows.The ESL of the third sample: about 405 pHThe ESL of the fourth sample: about 355 pH

Accordingly, based on the second experiment, it is understood that, in the substrate modules40band40c, the low ESL properties are more effectively achieved as compared to the substrate module40a.

FIG. 11is a graph illustrating the transmission characteristics (S21) of the first sample to the fourth sample. A vertical axis indicates attenuation, and a horizontal axis indicates a frequency.

According toFIG. 11, it is understood that the self-resonance frequency f3of the third sample is higher than the self-resonance frequency f1of the first sample. In addition, it is understood that the self-resonance frequency f4of the fourth sample is higher than the self-resonance frequency f3of the third sample. Specifically, the self-resonance frequency f4is about 2.25 GHz, the self-resonance frequency f3is about 2.115 GHz, and the self-resonance frequency f1is about 1.975 GHz. Accordingly, based on the experimental result inFIG. 11, it is understood that the high-frequency characteristics of the substrate modules40band40care improved as compared to the high-frequency characteristic of the substrate module40a.

Second Preferred Embodiment

Hereinafter, the configuration of an electronic component10aaccording to a second preferred embodiment of the present invention will be described with reference to drawings.FIG. 12is the exploded perspective view of a laminated body11aof the electronic component10aaccording to the second preferred embodiment.FIG. 13is the internal plan view of the electronic component10ainFIG. 12. In addition, since the external perspective view of the electronic component10ais the same or substantially the same as the external perspective view of the electronic component10,FIG. 1will be referred to.

As illustrated inFIG. 12, the laminated body11apreferably further includes a ceramic layer17iand internal conductors41and42.

As illustrated inFIG. 12, the ceramic layer17iis provided between a ceramic layer17aand a ceramic layer17b. The internal conductors41and42are preferably provided on the front surface of the ceramic layer17i, and arranged from the negative direction side in the x-axis direction to the positive direction side therein in this order in a state in which a clearance gap is provided between the internal conductors41and42.

As illustrated inFIG. 12andFIG. 13, the internal conductor41includes a capacitor conductor43, and extraction conductors44,47, and48. The capacitor conductor43preferably has a substantially rectangular shape, and provided within a half region on the negative direction side in the x-axis direction of the ceramic layer17i.

As illustrated inFIG. 12andFIG. 13, the extraction conductor44is connected to the capacitor conductor43, and extends to the end surface S3of the laminated body11, thereby being exposed from the end surface S3. More specifically, the extraction conductor44extends from a side on the negative direction side in the x-axis direction of the capacitor conductor43toward the negative direction side in the x-axis direction. Accordingly, the extraction conductor44extends to the short side on the negative direction side in the x-axis direction of the ceramic layer17i, and connected to the external electrode12a.

As illustrated inFIG. 12andFIG. 13, the extraction conductor47is connected to the capacitor conductor43and extends to the side surface S5of the laminated body11, thereby being exposed from the side surface S5. More specifically, the extraction conductor47extends from a side on the positive direction side in the y-axis direction of the capacitor conductor43toward the positive direction side in the y-axis direction. Accordingly, the extraction conductor47extends to a position, located on the negative direction side in the x-axis direction from the midpoint of the long side on the positive direction side in the y-axis direction of the ceramic layer17i, and connected to the external electrode13.

As illustrated inFIG. 12andFIG. 13, the extraction conductor48is connected to the capacitor conductor43and extends to the side surface S6of the laminated body11, thereby being exposed from the side surface S6. More specifically, the extraction conductor48extends from a side on the negative direction side in the y-axis direction of the capacitor conductor43toward the negative direction side in the y-axis direction. Accordingly, the extraction conductor48extends to a position, located on the negative direction side in the x-axis direction from the midpoint of the long side on the negative direction side in the y-axis direction of the ceramic layer17i, and connected to the external electrode14.

As illustrated inFIG. 12andFIG. 13, the internal conductor42includes a capacitor conductor45and extraction conductors46,49, and50. The capacitor conductor45preferably has a substantially rectangle shape, and provided within a half region on the positive direction side in the x-axis direction of the ceramic layer17i.

As illustrated inFIG. 12andFIG. 13, the extraction conductor46is connected to the capacitor conductor45, and extends to the end surface S4of the laminated body11, thereby being exposed from the end surface S4. More specifically, the extraction conductor46extends from a side on the positive direction side in the x-axis direction of the capacitor conductor45toward the positive direction side in the x-axis direction. Accordingly, the extraction conductor46extends to the short side on the positive direction side in the x-axis direction of the ceramic layer17i, and connected to the external electrode12b.

As illustrated inFIG. 12andFIG. 13, the extraction conductor49is connected to the capacitor conductor45and extends to the side surface S5of the laminated body11, thereby being exposed from the side surface S5. More specifically, the extraction conductor49extends from a side on the positive direction side in the y-axis direction of the capacitor conductor45toward the positive direction side in the y-axis direction. Accordingly, the extraction conductor49extends to a position, located on the positive direction side in the x-axis direction from the midpoint of the long side on the positive direction side in the y-axis direction of the ceramic layer17i, and connected to the external electrode15.

As illustrated inFIG. 12andFIG. 13, the extraction conductor50is connected to the capacitor conductor45and extends to the side surface S6of the laminated body11, thereby being exposed from the side surface S6. More specifically, the extraction conductor50extends from a side on the negative direction side in the y-axis direction of the capacitor conductor45toward the negative direction side in the y-axis direction. Accordingly, the extraction conductor50extends to a position, located on the positive direction side in the x-axis direction from the midpoint of the long side on the negative direction side in the y-axis direction of the ceramic layer17i, and connected to the external electrode16.

In the electronic component10including such a laminated body11aas described above, the intensity of the high-frequency signal flowing through the second path is increased. More specifically, the high-frequency signal preferably flows through the signal conductor54, the external electrode12a, the extraction conductor44, the capacitor conductor43, the extraction conductors47and48, the external electrodes13and14, the external electrodes15and16, the extraction conductors49and50, the capacitor conductor45, the extraction conductor46, the external electrode12b, and the ground electrode55in this order. That is, the high-frequency signal flows through a path equivalent to the second path. As a result, in the electronic component10including the laminated body11a, the high-frequency characteristics thereof are improved.

Third Preferred Embodiment

Hereinafter, the configuration of an electronic component10baccording to a third preferred embodiment of the present invention will be described with reference to drawing.FIGS. 14A and 14Bare the internal plan views of the electronic component10baccording to the third preferred embodiment. In addition, since the external perspective view of the electronic component10bis the same or substantially the same as the external appearance perspective view of the electronic component10,FIG. 1will be referred to.

As illustrated inFIGS. 14A and 14B, the electronic component10bdiffers from the electronic component10in that the extraction conductors23and25are preferably not provided. In this case, the electronic component10bis preferably mounted so that the side surface S5faces the circuit substrate51. Since the external electrodes13to16are not provided on the top surface S1and the bottom surface S2of the electronic component10, the width of the electronic component10in the z-axis direction can be reduced. As a result, it is possible to arrange the electronic components10so that the electronic components10are adjacent to each other.

Fourth Preferred Embodiment

Hereinafter, the configuration of an electronic component10caccording to a fourth preferred embodiment of the present invention will be described with reference to the drawings.FIGS. 15A and 15Bare internal plan views of the electronic component10caccording to the fourth preferred embodiment. In addition, since the external perspective view of the electronic component10cis the same or substantially the same as the external appearance perspective view of the electronic component10,FIG. 1will be referred to.

The electronic component10cdiffers from the electronic component10in that the electronic component10cpreferably includes extraction conductors72(72ato72c),73(73ato73c),74(74ato74c), and75(75ato75c).

The extraction conductor72is connected to the connection conductor20, and extends to the side surface S5of the laminated body11c, thereby being exposed from the side surface S5. More specifically, the extraction conductor72extends from the midpoint of a side on the positive direction side in the y-axis direction of the connection conductor20toward the positive direction side in the y-axis direction. Accordingly, the extraction conductor72extends to a position on the long side on the positive direction side in the y-axis direction of the ceramic layer17, the position being located on the negative direction side in the x-axis direction from the extraction conductor22, and the extraction conductor72is connected to the external electrode12a.

The extraction conductor73is connected to the connection conductor20and extends to the side surface S6of the laminated body11c, thereby being exposed from the side surface S6. More specifically, the extraction conductor73extends from the midpoint of a side on the negative direction side in the y-axis direction of the connection conductor20toward the negative direction side in the y-axis direction. Accordingly, the extraction conductor73extends to a position on the long side on the negative direction side in the y-axis direction of the ceramic layer17, the position being located on the negative direction side in the x-axis direction from the extraction conductor23, and the extraction conductor73is connected to the external electrode12a.

The extraction conductor74is connected to the connection conductor21and extends to the side surface S5of the laminated body11c, thereby being exposed from the side surface S5. More specifically, the extraction conductor74extends from the midpoint of a side on the positive direction side in the y-axis direction of the connection conductor21toward the positive direction side in the y-axis direction. Accordingly, the extraction conductor74extends to a position on the long side on the positive direction side in the y-axis direction of the ceramic layer17, the position being located on the negative direction side in the x-axis direction from the extraction conductor24, and the extraction conductor74is connected to the external electrode12b.

The extraction conductor75is connected to the connection conductor21and extends to the side surface S6of the laminated body11c, thereby being exposed from the side surface S6. More specifically, the extraction conductor75extends from the midpoint of a side on the negative direction side in the y-axis direction of the connection conductor21toward the negative direction side in the y-axis direction. Accordingly, the extraction conductor75extends to a position on the long side on the negative direction side in the y-axis direction of the ceramic layer17, the position being located on the positive direction side in the x-axis direction from the extraction conductor25, and the extraction conductor75is connected to the external electrode12b.

Since the extraction conductors72to75are provided in the electronic component10c, the number of current paths within the electronic component10cis greater than the number of current paths within the electronic component10. As a result, in the electronic component10c, the low ESL property is more effectively achieved.

In addition, in the electronic component10c, it is preferable that the extraction conductors72to75are not provided at the corner of the ceramic layer17.

Fifth Preferred Embodiment

Hereinafter, the configuration of an electronic component10daccording to a fifth preferred embodiment of the present invention will be described with reference to the drawings.FIG. 16is the external appearance perspective view of the electronic component10daccording to the fifth preferred embodiment.

As illustrated inFIG. 16, the external electrode13and the external electrode14may preferably be connected to each other using external electrodes provided on the top surface S1and the bottom surface S2. In the same manner, the external electrode15and the external electrode16may be connected to each other using external electrodes provided on the top surface S1and the bottom surface S2. In addition, the inner structure of the electronic component10dmay be any one of the inner structures of the electronic components10and10ato10c.

Sixth Preferred Embodiment

Hereinafter, the configuration of an electronic component10eaccording to a sixth preferred embodiment of the present invention will be described with reference to a drawing.FIG. 17is the external appearance perspective view of the electronic component10eaccording to the sixth preferred embodiment.

As illustrated inFIG. 17, each of the external electrodes13and15may preferably be only provided on the side surface S5and may not extend to the top surface S1or the bottom surface S2. In the same manner, each of the external electrodes14and16may preferably be only provided on the side surface S6and may not extend to the top surface S1or the bottom surface S2.

When the distance between the external electrodes13and15and the distance between the external electrodes14and16are reduced, the external electrodes13to16may be formed using direct plating, for example. In the direct plating, the external electrodes13to15are preferably formed so that the extraction conductors22to25cover exposed portions. Accordingly, in this case, the external electrodes13to15are not formed on the top surface S1and the bottom surface S2.

The electronic components10and10ato10eand the substrate modules40ato40caccording to various preferred embodiments of the present invention are not limited to those illustrated in the above-mentioned preferred embodiments, and modifications may be made within the scope of the present invention.

In addition, instead of the ceramic layer17, a resin material, such as epoxy resin, polypropylene, or other suitable material may be used.

As described above, preferred embodiments of the present invention are useful for an electronic component and a substrate module, and in particular, have advantages in that low ESL properties are achieved and a short circuit is prevented from occurring when the electronic component and the substrate module are mounted on a circuit substrate.