JPH10303067A - Cr element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a CR element of large electrostatic capacity with no increased element size nor limit on a dielectric material which is used. SOLUTION: Relating to a CR element wherein a dielectrics layer 3 and a resistor layer 5 are allocated in series on a substrate 1, a facing electrode 10B is formed in the dielectrics layer 3, to constitute such dielectrics layer 3 of multi layered structure. With the dielectrics layer 3 as multi layered structure, an electrostatic capacity at a capacity part is increased without increasing the size of element or change of dielectrics material.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CR element having a capacitor function and a resistance function, and particularly to a large capacitance without increasing the element size and without being restricted by a dielectric material used. C that can get
It relates to an R element.

[0002]

2. Description of the Related Art A CR element is inserted between an integrated circuit of a computer and ground to remove noise in a signal.

FIG. 2 is a sectional view showing a conventional CR element used for such a purpose. In this CR element, a lower electrode 2A as a capacitor, a dielectric layer 3 and an upper electrode 4 are laminated on one half of the alumina substrate 1, and the other half of the CR element is provided between the lower electrode 2A and the lower electrode 2B. To resistance layer 5
Are provided to form a resistor. Back electrodes 6A and 6B are formed on the back surface of the alumina substrate 1, and terminal electrodes 7A and 7B are provided on both end edges. And
The capacitor portion is covered with the first glass layer 8, and the entire capacitor portion and the resistor portion are further covered with the second glass layer 9.

[0004]

In the above-mentioned conventional CR element, since the capacitor has only one dielectric layer, in order to increase the capacitance, a dielectric material having a large relative dielectric constant must be used. Alternatively, the area of the capacitor portion must be increased. Therefore, it is necessary to increase the element size.

[0005] However, selecting a dielectric material having a large relative dielectric constant is industrially disadvantageous in that the dielectric material to be used is restricted and the material cost rises. Also,
The increase in the size of the element leads to an increase in the size of the circuit, which goes against recent technical demands for miniaturization of all devices.

The present invention solves the above-mentioned conventional problems, and has a large capacitance without increasing the element size and without being restricted by the dielectric material used.
It is intended to provide an element.

[0007]

According to the CR element of the present invention, in a CR element having a dielectric layer and a resistance layer arranged in series on a substrate, opposed electrodes are formed between the dielectric layers. Thus, the dielectric layer has a multilayer structure.

By forming opposing electrodes between the dielectric layers and forming the dielectric layers into a multilayer structure, the capacitance of the capacitor portion can be reduced without increasing the element size and without changing the dielectric material. The electric capacity can be increased.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a CR device according to the present invention will be described in detail with reference to the drawings.

FIG. 1 is a view showing an embodiment of a CR element according to the present invention. FIG. 1 (a) is a sectional view and FIG. 1 (b) is a plan view. In FIG. 1, members having the same functions as those shown in FIG. 2 are denoted by the same reference numerals. FIG.
In (b), the first and second glass layers 8, 9 and the terminal electrodes 7A, 7B are not shown.

In this CR element, a capacitor and a resistor are connected in series, and the structure of a resistor provided on one half of one plate surface of the alumina substrate 1 is a conventional CR element shown in FIG. Like the element, the lower electrodes 2A and 2B and the resistance layer 5
The capacitor provided on the other half side includes a lower electrode 10A, an intermediate electrode 10B, and an upper electrode 10C.
And the dielectric layer 3 (3A, 3B)
Different from R element.

That is, the capacitor portion of the CR element of the present embodiment has the intermediate electrode 1 at an intermediate position in the thickness direction of the dielectric layer 3.
By providing 0B, the dielectric layer 3 has a two-layer structure of a lower dielectric layer 3A and an upper dielectric layer 3B. The upper electrode 10C is provided so as to conduct from the upper surface of the dielectric layer 3 to the lower electrode 10A.
Is provided so as to conduct from the inside of the dielectric layer 3 to the lower electrode 2A of the resistor.

In this CR element, a large capacitance can be obtained by forming the dielectric layer 3 into a two-layer structure with the intermediate electrode 10B.

In order to manufacture such a CR element, first, Ag, Pd, Pt,
Precious metals such as Au, Ag / Pd, Ag / Pt or Ni, C
a conductive paste containing a base metal powder such as u
By firing at 0 to 900 ° C, the lower electrodes 10A, 2
A, 2B and back electrodes 6A, 6B are printed.

Next, a paste of dielectric ceramics is printed and baked at 800 to 900 ° C. to form the lower dielectric layer 3A. The printing and firing of the paste
It may be repeated several times so as to obtain a dielectric layer having a predetermined thickness.

Thereafter, the intermediate electrode 10B is formed on the lower dielectric layer 3A so as to be continuous with the lower electrode 2A in the same manner as in the method of forming the lower electrode, and the upper dielectric layer 3B is formed in the same manner as above. I do. Further, an upper electrode 10C continuous with the lower electrode 10A is printed and baked on the upper dielectric layer 3B in the same manner as in the method of forming the lower electrode described above, and then a paste for protective glass is printed to 600 to 850.
The first glass layer 8 is formed by baking at ℃.

Next, the resistance layer 5 is formed by printing a ceramic paste of a resistance material and firing at 800 to 900 ° C. The printing and baking of the paste may be repeated several times so that a resistance layer having a predetermined thickness is obtained.

After that, the second glass layer 9 is formed by printing a paste for a protective glass and baking it at 600 to 850 ° C.

Finally, the terminal electrodes 7A and 7B are printed and baked, and then Ni plating and solder plating are performed to obtain a CR element.

In the present invention, a ceramic substrate such as mullite can be used as a substrate in addition to an alumina substrate. In a normal case, the thickness of such an insulating substrate is 0.1 mm.
It is about 4-0.6 mm.

The conductive paste used for forming the upper electrode, the intermediate electrode, and the lower electrode is preferably a conductive paste containing a metal powder and a glass frit and suitable for thick film printing.

The upper electrode, the intermediate electrode and the lower electrode are preferably formed with such a conductive paste to a thickness of about 5 to 15 μm. In addition, each layer 3A of the dielectric layer 3,
3B has a thickness of 5 to 30 μm, and the resistance layer 5 has a thickness of 5 to 15 μm.
μm, the thickness of the first glass layer 8 is 10 to 30 μm, and the thickness of the second glass layer 9 is 10 μm above the first glass layer 8.
It is preferably about 30 μm.

It should be noted that the dielectric material, the resistance material, and the first,
The glass material of the second glass layer is not particularly limited, and a glass material used for a general CR element can be used.
Usually, as a dielectric material, a lead relaxer-based material,
In addition, a barium titanate-based material or the like can be used, and a RuO ₂ glass-based material or the like can be used as a resistance material. As the glass material of the first glass layer, it is generally preferable to use crystallized glass in order to suppress the reaction between the second glass layer and the dielectric layer. As the protective glass material of the second glass layer, amorphous glass is preferably used. It is suitable.

Although FIG. 1 shows an example in which the dielectric layer has a two-layer structure with one intermediate electrode, the present invention is not limited to this, and the dielectric layer is provided by providing two or more intermediate electrodes. The body layer can have a multilayer structure of three or more layers.

Such a CR element of the present invention can be easily connected to a circuit simply by wiring the terminal electrodes 7A and 7B at both ends.

This CR element has a smaller capacitance than a conventional CR element using the same dielectric material and having the same mounting area in accordance with the number of dielectric layers stacked by forming the intermediate electrode. Can be greatly increased. This capacitance is much larger than the case where the thickness of the dielectric layer is simply increased without providing the intermediate electrode.

[0027]

The present invention will be described more specifically below with reference to examples and comparative examples.

Examples 1 to 3 CR devices of the present invention shown in FIG. 1 were produced.

First, a conductive paste (“5424” manufactured by DuPont) was printed on the alumina substrate 1 and the paste was heated at 850 ° C. for 1 hour.
By firing for 0 minutes, the lower electrode 2 having a thickness of 10 μm is formed.
A, 2B, 10A and back electrodes 6A, 6B were formed.

Next, a dielectric ceramic paste (“5530” manufactured by DuPont) was printed and baked at 850 ° C. for 10 minutes to form a lower dielectric layer 3A having a thickness of 20 μm.

Next, in the same manner as the lower electrode,
μm, the area on the lower dielectric layer 3A is 0.2322 mm
After forming the ^second intermediate electrode 10B, the lower dielectric layer 3
An upper dielectric layer 3B having a thickness of 20 μm is formed in the same manner as in A, and further, a 10 μm thickness is formed in the same manner as the lower electrode.
Upper electrode 1 whose area on dielectric layer 3 is as shown in Table 1.
0C was formed.

Thereafter, the crystallized glass paste is printed, dried and baked at 850 ° C. to form a first glass layer 8 having a thickness of 20 μm, and then a resistance material paste (manufactured by Sumitomo Metal Co., Ltd.) is printed. The resistor layer 5 having a thickness of 10 μm was formed by baking at 850 ° C. for 10 minutes, and the second glass layer 9 was formed by printing and drying the amorphous glass paste at 600 ° C.

Finally, terminal electrodes 7A and 7B are formed, and N
i-plating and solder plating were performed to obtain a CR element.

The element size of this CR element is 3.2 mm ×
1.6 mm, and its capacitance was as shown in Table 1.

Comparative Examples 1 to 6 In the same manner as in the conventional CR device shown in FIG. 2 except that the intermediate electrode was not formed and a single-layer dielectric layer having a thickness shown in Table 1 was formed. Produced. However, the area of the upper electrode 4 on the dielectric layer 3 was as shown in Table 1. The dimensions of this CR element were 3.2 mm × 1.6 mm, which were equivalent to those of Examples 1 to 3, and the capacitance was as shown in Table 1.

As apparent from Table 1, according to the present invention,
By using the same dielectric material, a large capacitance can be obtained without increasing the element size.

[0037]

[Table 1]

[0038]

As described in detail above, according to the CR element of the present invention, a high-capacity CR element having a small element area, a small mounting area is sufficient, and a circuit can be miniaturized is provided at low cost. .

[Brief description of the drawings]

FIG. 1 is a view showing an embodiment of a CR element according to the present invention, wherein FIG. 1 (a) is a sectional view and FIG. 1 (b) is a plan view.

FIG. 2 is a cross-sectional view showing a conventional CR element.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Alumina substrate 2A, 2B Lower electrode 3 Dielectric layer 3A Lower dielectric layer 3B Upper dielectric layer 4 Upper electrode 5 Resistive layer 6A, 6B Back electrode 7A, 7B Terminal electrode 8 First glass layer 9 Second glass layer 10A Lower part Electrode 10B Intermediate electrode 10C Upper electrode

Claims (1)

[Claims] In a CR device in which a dielectric layer and a resistance layer are arranged in series on a substrate, opposing electrodes are formed between the dielectric layers so that the dielectric layer has a multilayer structure. A CR element, characterized in that: