JPH02185007A - Laminated ceramic electronic parts - Google Patents

Abstract

PURPOSE:To minutely adjust an electric characteristic by forming a hole extending from a laminating direction external surface to the inside on a sintered body while exposing a part of an internal conductor to this hole. CONSTITUTION:An LC filter device 11 has a construction, in which an internal electrode 13 for constituting inductance and internal electrodes 14 to 16 for constituting capacitors are formed inside a ceramic sintered body 12. The internal electrode 13 is connected to the internal electrode 14 through a throughhole 20 and a pair of external electrodes 17 and 18 are formed on the opposing end faces of the sintered body 12. In this case, a hole 21 extending from the laminating direction external surface to the internal conductor direction is formed on the sintered body 12, and an internal conductor is partly exposed to this hole so that trimming can be performed while using the hole 21 by an optical method such as laser light or the like. Thereby, an electric characteristic such as capacitance value and inductance value can be accurately adjusted.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to the improvement of multilayer ceramic electronic components such as multilayer capacitors and multilayer LC filters, and in particular, to the improvement of multilayer ceramic electronic components such as multilayer capacitors and multilayer LC filters, and in particular, to the improvement of multilayer ceramic electronic components such as multilayer capacitors and multilayer LC filters. Concerning a given structure.

[Conventional technology]

In a multilayer capacitor, the capacitance value is set by adjusting the size of the stacked electrodes and the number of stacked electrodes. However, if a capacitance value outside the standard is required, for example, more detailed capacitance adjustment is recommended. A structure shown in FIG. 2 has been proposed as a structure capable of performing such fine capacity adjustment.

In the multilayer capacitor 1 shown in FIG. 2, a plurality of internal electrodes 3 to 5 are arranged in a ceramic sintered body 2 so as to overlap each other with ceramic layers interposed therebetween. The capacitance based on the ceramic layer between the internal electrodes 3 to 5 is taken out between the external electrodes 6 and 7 formed on opposite end surfaces of the sintered body 2.

In the multilayer capacitor 1, a trimming electrode 8 is formed on the outer surface of the sintered body 2 in order to more finely adjust the capacitance value. The trimming river mist 8i8 is arranged so as to overlap the internal electrode 3 via the ceramic layer, and is connected to the external electrode 7. When adjusting the capacitance value, the trimming electrode 8 is trimmed by a sandblasting method or a method using a laser while measuring the capacitance.

[Technical problem to be solved by the invention] However,
Since the entire surface of the trimming electrode 8 is exposed on the outer surface, it is not only necessary to cover the trimming electrode 8 with a resin or the like after trimming, but also to cover the trimming electrode 8 with an internal electrode (for example, an internal electrode). 4) required electrical connection work.

Similar problems occur with other laminated ceramic electronic components. In addition, in high-frequency circuit devices, when trimming electrodes are formed on the surface of the sintered body, as in the case where LC filters are constructed of laminated ceramic components, reflection of high-frequency signals may occur at the trimming electrode portions, and external noise may be generated. become more susceptible.

Therefore, an object of the present invention is to provide a multilayer ceramic electronic component having a structure that allows the formation of an extra coating layer to be omitted and allows fine adjustment of electrical characteristics such as capacitance value. There is a particular thing.

(Means for Solving Technical Problems) The present invention provides a multilayer ceramic electronic component in which an internal conductor is formed within a ceramic sintered body, in which a hole extending inward from the outer surface in the lamination direction is formed in the sintered body. It is characterized by a part of the internal conductor being exposed in this hole.

(Function) A hole is formed that extends inward from the outer surface in the stacking direction of the sintered body, and a part of the internal conductor is exposed in the hole, so trimming can be performed using this hole. Therefore, by trimming the internal conductor, electrical characteristics such as capacitance and inductance can be adjusted with high precision.

This hole may be sealed with a sealing material after trimming, and therefore there is no need to form a large-scale covering layer as in the conventional example.

[Explanation of Examples]

FIG. 1 is a sectional view showing a multilayer ceramic electronic component according to an embodiment of the present invention, and FIG. 3 is an exploded perspective view of an upper portion of the embodiment before sintering. This embodiment is applied to an LC filter device.

The LC filter device 11 includes, in the ceramic sintered body 12,
It has a structure in which an internal electrode 13 for forming an inductance and internal electrodes 14 to 16 for forming a capacitor are formed. Internal electrode 13 is through hole 2
0 is connected to the internal electrode 14. A pair of external electrodes 17 and 18 are provided on opposing end surfaces of the sintered body 12 by a known external electrode forming method.

The internal electrode 13 as an internal conductor is constituted by a spiral electrode pattern, as shown by hatching in FIG. 3.

In actual manufacturing, ceramic green sheets with electrode paste for forming internal electrodes 13 to 16 printed on one main surface are laminated and sintered to create a sintered body.
Get 2.

The feature of this embodiment is that among the internal electrodes 13 to 16, an electrode land 13 for trimming is provided on the internal electrode I3 for forming the inductance, as shown in FIG.
As shown in FIG. 1, the electrode land 13a is exposed in a hole 21 extending inward from the outer surface of the sintered body 12 in the stacking direction. Hole 21 is the third
As shown in the figure, ceramic green sheets 22 coated with electrode paste for forming internal electrodes 13 are
It is formed by laminating ceramic green sheets 23 and 24 in which through holes 23a and 24a are formed, respectively, and firing them together. Note that 20a in FIG. 3 indicates a hole for forming a through hole.

In the LC filter device tt shown in FIG. 1, the electrode land 13a of the internal electrode 13 is exposed in the hole 21.

Therefore, it is possible to irradiate, for example, a laser beam through this hole 21 and thereby trim the electrode land 13a, thereby accurately adjusting the inductance value to a desired value.

Note that since the hole 21 is formed for trimming the electrode land 13a using an optical means such as a laser beam, the shape of the opening does not matter, and the size of the hole 21 also does not matter. This varies depending on the amount to be trimmed and the optical trimming method, and is not particularly limited, but is usually formed to have a diameter of about 0.5 to 2.0 mm.

Furthermore, preferably, the ceramic green sheet 23.
24, a ceramic green sheet 3 whose through holes are filled with carbon paste 32 as shown in FIG.
1 is used. Since the carbon paste 32 is filled, multiple ceramic green sheets are laminated,
When pressure bonding is performed in the thickness direction prior to firing, the through hole can be prevented from being crushed by the upper and lower ceramic green sheets. Furthermore, since the carbon paste 32 scatters after firing, the holes 21 of a desired size can be reliably formed. Instead of the carbon paste 32, various materials that can be scattered at the firing temperature, such as an organic binder paste, may be used.

In the above embodiment, the electrode land 13 of the internal electrode 13 as an internal conductor is formed over the entire opening area of the hole 21.
a is exposed (see Figures 1 and 3). However, the present invention is not limited to this, and the internal conductor may be exposed only in a part of the opening area of the hole.

Also, the hole 21 may be left as is, but
Preferably, glass or insulating resin may be filled and sealed by sintering or hardening. By sealing with glass or insulating resin in this way,
The interior of the ceramic sintered body 12 can be kept airtight, and therefore a laminated electronic component with excellent reliability can be obtained.

Furthermore, although the above embodiments are applied to LC filter devices, it is pointed out that the present invention can be applied to various multilayer ceramic electronic components in general, such as multilayer capacitors, multilayer coils, and multilayer ceramic multilayer substrates. put.

〔Effect of the invention〕

As described above, in the present invention, a hole extending from the outer surface in the stacking direction toward the internal conductor is formed in the sintered body, and a part of the internal conductor is exposed in this hole. Trimming can be performed using an optical method such as a laser beam.

Therefore, it becomes possible to adjust electrical characteristics such as capacitance value and inductance value with high precision.

In addition, in the conventional example shown in Figure 2, a large area resin coating layer had to be formed to cover the entire exposed trimming electrode, whereas according to the present invention, a large area of the resin coating layer was required to cover the entire exposed trimming electrode. Since only the portion is exposed through the hole, such a large-scale covering layer can be omitted.

Furthermore, since the internal conductor for trimming is disposed within the ceramic sintered body, signal reflection is unlikely to occur even when used in a high frequency circuit such as an LC filter. Similarly, it becomes less susceptible to the effects of internal noise. Therefore, it is possible to realize a highly reliable multilayer ceramic electronic component.

[Brief explanation of the drawing]

Figure 1 is a sectional view of an embodiment of the present invention, Figure 2 is a sectional view of a conventional multilayer ceramic electronic component, and Figure 3 is for explaining a ceramic green sheet used to obtain the embodiment of Figure 1. FIG. 4 is a cross-sectional view of a ceramic green sheet whose through holes are filled with carbon paste. In the figure, 11 is L as a multilayer ceramic electronic component.
C filter device, 12 is a ceramic sintered body, 13 to 16
is an internal electrode as an internal conductor, 21 is a hole, 22 to 24
23a and 24a are ceramic green sheets, and 23a and 24a are through holes for forming holes. Figure 2 Figure 4

Claims (1)

[Claims] In a multilayer ceramic electronic component having a structure in which an internal conductor is formed within a ceramic sintered body, the sintered body includes:
A hole is formed that extends from the outer surface in the stacking direction to the inside.
A multilayer ceramic electronic component, wherein a part of the internal conductor is exposed in the hole.