JPH0360106A - Laminated chip inductor - Google Patents

Abstract

PURPOSE:To avert the effect of static induction or electromagnetic induction between inductance elements vertically close to by a method wherein a substrate sheet on almost the whole surface on which an electrode is provided is laid between the inductance elements in laminated state and then the electrode is grounded. CONSTITUTION:A substrate sheet 8 is formed of a non-magnetic material or a magnetic material, as for the non-magnetic material, various ceramics are applicable while as for the magnetic material, a ferrite e.g. similar to the sheets 1-5 is applicable. Almost the whole surface of this sheet 8 leaving both ends wherein outer leading-out electrodes 10a, 11a are positioned is coated with a conductive paste to form an electrode 14 as shown shaded by oblique lines. Accordingly, inner electrodes 10, 11 fill the role of inductance elements; the electrode 14 is laid between the inner electrodes 10, 11 positioned vertically close to be grounded through an outer electrode 24 so that the effect of static induction may be averted. Furthermore, since the substrate sheet 8 is formed of the non-magnetic material, the effect of electromagnetic induction between the inner electrodes 10, 11 can be averted regardless of the existance of the electrode 14.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a multilayer chip inductor having a chip structure by stacking a plurality of inductance elements.

Different speed! Conventionally, various types of multilayer chip inductors have been known in which internal electrodes are provided on an insulating magnetic sheet in the form of a straight or coiled shape, and a plurality of these sheets are laminated, as shown in Fig. 6. , an example is shown in FIG.

In Figure 6, 1, 3, and 4.5 are ferrite green sheets, and on the sheets 4 and 5, internal electrodes 10, 10, 11, and 11 that function as inductance elements are made into straight shapes by applying IT paste. The external lead electrodes 10a and 10a are formed at both ends.

The sheets 4 and 5 are interposed with the required number of dummy sheets 3,
Further, dummy sheets 1 and 2 are stacked on top and bottom of the dummy sheets 1 and 2, and the dummy sheets are laminated under pressure and fired. After that, barrel polishing or surface polishing is performed, and as shown in FIG. 7, a pair of external electrodes 20 to 23 are formed by coating and baking a conductive paste on both ends.
It is considered to be a multilayer Chi-nobu inductor.

By the way, in this type of laminated chip inductor, the influence of electrostatic induction and electromagnetic induction between individual inductance elements becomes a problem, and internal electrodes 10.
0 and 11.11 can be provided with a sufficient distance without any influence, but between the internal electrodes 10.11 which are close to each other in the vertical direction, the distances a and b shown in Fig. 8 become a problem, and electrostatic induction and It is affected by electromagnetic induction.

Increasing the distances a and b means that the chip itself becomes larger,
Moreover, it is not a desirable countermeasure because it cannot completely eliminate the effects.

Therefore, an object of the present invention is to provide a multilayer chip inductor without making the distances a and b unnecessarily large.
The objective is to eliminate the influence of electrostatic induction or electromagnetic induction between vertically adjacent inductance elements.

Means and Production for Solving the Problems In order to achieve the above-mentioned problems, the multilayer chip inductor according to the present invention has a base sheet provided with electrodes on almost the entire surface thereof, interposed between the laminated inductance elements. By grounding the electrode, electrostatic induction between adjacent inductance elements sandwiching the electrode is prevented. Also,
If the base sheet provided with the electrodes is made of a non-magnetic material, electromagnetic induction between vertically adjacent inductance elements can also be prevented. On the other hand, only a nonmagnetic sheet may be provided without providing an electrode, and in this case, electromagnetic induction between vertically adjacent inductance elements is prevented.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of a multilayer chip inductor according to the present invention will be described with reference to the accompanying drawings.

[See Embodiment 1, Figures 1 and 2] Figure 1 shows each element of the inductor before lamination, and is basically composed of the same elements as the conventional laminated chip inductor shown in Figure 1. has been done.

That is, ferrite green sheets 1 to 5 are obtained by kneading ferrite powder, an organic solvent, a binder, etc. to form a slurry, and then forming the sheet into a sheet by an extrusion method, a pulling method, a blade method, or the like. Among these base sheets, a conductive paste containing Ag, Ag-Pd, etc. is applied to the surfaces of sheets 4 and 5, and internal electrodes 10.10 and 11.11 as inductance elements are formed.
External extraction electrodes 10a and lla are formed at both ends. Note that the internal electrodes 10 and 11 are formed so as not to overlap each other.

The base sheet 8 is made of a non-magnetic material or a magnetic material depending on its purpose, and the non-magnetic material is, for example, various ceramics, and the magnetic material is, for example, ferrite similar to the sheets 1 to 5. On this sheet 8, the external extraction electrode I
A conductive paste is applied to almost the entire surface except for both ends where Qa and lla are located, and electrodes 14 shown by diagonal lines are formed.

Sheet 8 and dummy sheet 3.3 and dummy sheets 1 and 5 above and below are placed between sheets 4 and 5 having the above configuration.
Stack the required number of each and apply pressure. In the actual mass production process, each sheet 4, 5.8 is a wide sheet printed with a large number of conductors, which are laminated at once and cut to form one unit of inductor as shown in FIGS. 1 and 2. After firing this at an appropriate temperature and performing barrel polishing, surface polishing, etc., the external lead electrodes 10a, lla and electrode 1 exposed to the outside are
A conductive paste is applied and baked at positions corresponding to both ends of 4 to form external electrodes 20 to 23 and a grounding external electrode 24.

In the multilayer chip inductor with the above configuration,
The internal electrodes 10.10.11.11 function as inductance elements, and the electrode 14 is interposed between the vertically adjacent internal electrodes 10 and 11, and grounding is established through the external electrode 24, thereby preventing electrostatic induction. influence is eliminated. Furthermore, by forming the base sheet 8 from a non-magnetic material, the influence of electromagnetic induction between the internal electrodes 10 and 11 is eliminated regardless of the presence or absence of the electrodes 14. On the other hand, if the base sheet 8 is made of a magnetic material, only the effects of electrostatic induction can be eliminated by the function of the electrodes 14.

[See Second Example, Figures 3 to 5] The multilayer chip inductor of this second example has an internal electrode 10 functioning as an inductance element, as shown in Figure 5, in its final form as a product. ~13 are stacked in a row, so to speak, the distance 1Iib shown in FIG.
That is.

Its production consists of forming internal electrodes 10 to 13 on ferrite green sheets 4 to 7, respectively, and base material sheet 8.
An electrode 14 shown by diagonal lines is formed on the entire surface of the electrode, and a required number of dummy sheets 3 are interposed therebetween, and the dummy sheets 1.degree..2 are stacked one above the other and pressed. Thereafter, the inductor is cut into one unit along the cut line shown by the dashed line in FIG. 4 so that the internal electrodes 10 to 13 arranged in parallel are separated, and this is fired at an appropriate temperature. moreover,
After performing barrel polishing, surface polishing, etc., a conductive paste is applied and baked on each of the external extraction electrodes 10a to 13a exposed to the outside to form external electrodes 25 to 28. At the same time, a conductive paste is applied and baked across the ends of each electrode 14 exposed to the outside to form an external grounding electrode 29.

In the above configuration, the function of the electrode 14 and the base sheet 8
The function of the (magnetic material or non-magnetic material) is the same as that described in the first embodiment, and electrostatic induction and electromagnetic induction between the internal electrodes 10, 11, 12, 13 that are close to each other in the vertical direction. Impact is prevented.

Note that the multilayer chip inductor according to the present invention is not limited to the above-mentioned embodiments, and can be variously modified within the scope of the gist.

In particular, the number of inductance elements or the number of laminated layers formed on one sheet 4 to 7 is arbitrary, and it may be a composite electronic component combined with a capacitor element etc.
In the second embodiment, the electrode 14 on the base sheet 8 is
As in the embodiment, it may be formed over almost the entire surface, leaving both ends intact.

As is clear from the above explanation, according to the present invention, a base sheet having electrodes provided on almost the entire surface is interposed between the laminated inductance elements. Electrostatic induction between the inductance elements can be prevented, the distance between the inductance elements can be reduced, and further miniaturization is possible. Furthermore, if the base sheet is made of a non-magnetic material, electromagnetic induction between adjacent inductance elements can be prevented by sandwiching the base sheet.

[Brief explanation of drawings]

FIG. 1 is an exploded perspective view of an inductor according to a first embodiment of the present invention before lamination, and FIG. 2 is a perspective view of the inductor shown in FIG. 1 laminated and provided with external electrodes. FIG. 3 is an exploded perspective view of an inductor according to a second embodiment of the present invention before lamination, FIG. 4 is a perspective view of the inductor in FIG. 3 in a laminated state, and FIG. It is a perspective view in a state cut into units and provided with external electrodes. Fig. 6 is an exploded perspective view of a conventional inductor before lamination, Fig. 7 is a perspective view of the inductor in Fig. 6 laminated and with external electrodes provided, and Fig. 8 is a vertical cross-section of the inductor in Fig. 7. It is a diagram. 1-7... Ferrite green sheet, 8... Base material (magnetic or non-magnetic) sheet 1.10-13... Internal electrode (inductance element), 14... Electrode, 20-2
3, 25-28...external electrode, 24.29... external electrode for grounding. Figure 1 Figure 2 Figure 6 Figure 7 Figure 8

Claims (3)

[Claims] 1. In a multilayer chip inductor formed by laminating base sheets provided with inductance elements, a base sheet provided with electrodes on almost the entire surface is interposed between the laminated inductance elements, and an external electrode for grounding is attached to the electrode. A multilayer chip inductor characterized in that it is attached. 2. The multilayer chip inductor according to claim 1, wherein the base sheet on which the electrodes are provided is made of a non-magnetic material. 3. A multilayer chip inductor formed by laminating base sheets provided with inductance elements, characterized in that a nonmagnetic sheet is interposed between the laminated inductance elements.