JPH06112008A - Resistor - Google Patents

Abstract

PURPOSE:To decrease the irregularity in resistance characteristics, to improve the resistance against environmental moisture and the like, and to obtain a resistor having a large power capacity. CONSTITUTION:At least a resistance film 4 is buried in a ceramic sintered body 3, and a resistor 1 is formed. Ceramic material, consisting of ZnO as the main component and zinc borosilicate glass and/or lead/zinc borosilicate glass as an auxiliary compound, is used for the sintered body.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resistor capable of reducing variations in resistance characteristics, improving environment resistance characteristics against humidity and the like, and increasing power capacity.

[0002]

2. Description of the Related Art Conventionally, a cermet resistor mainly composed of Ru oxide or Ru compound has been widely used as a resistive element having excellent accuracy. Such a resistor is formed, for example, by forming a thick resistive film on the surface of an alumina substrate by printing a resistive paste made of the above Ru oxide or the like.
Bake at 0 to 900 ° C. Then, a glass paste is applied to the surface of the resistance film of the alumina substrate and then baked to form a glass film, thereby improving environmental resistance against humidity and the like.

[0003]

However, the above-mentioned conventional resistor has a problem that the resistance value is likely to change because the resistance film is directly coated with glass and the characteristics are likely to vary. In addition, pinholes may be formed in the glass film, and as a result, there is also a problem that moisture or the like enters through the pinholes in an atmosphere of high humidity to deteriorate resistance characteristics. Furthermore, in the above conventional resistor, since the alumina substrate, the resistive film, and the glass film have different thermal expansion coefficients, the adhesiveness of the resistive film to the substrate is low. Was the limit.

The present invention has been made in view of the above-mentioned conventional circumstances, and provides a resistor capable of reducing variations in resistance characteristics, improving environmental resistance to humidity, and obtaining a large power capacity. It is an object.

[0005]

SUMMARY OF THE INVENTION Therefore, according to the present invention, at least one resistance film is embedded inside a ceramics sintered body, and the sintered body contains ZnO as a main component, and zinc borosilicate is added thereto. The resistor is characterized by being configured to contain 0.1 to 10% by weight of either or both of glass and lead zinc borosilicate glass in total.

Here, the above-mentioned glass content is limited because if the glass content is less than 0.1 wt%, the effect of improving the resistance characteristics cannot be obtained, and if it exceeds 10 wt%, the sintered body and the resistance film are not provided. Is likely to occur, resulting in a large variation in characteristics and a reduction in power capacity.

In order to manufacture the resistor, the Z
A plurality of ceramic sheets obtained by adding zinc borosilicate glass or the like to nO are laminated with the resistive film interposed therebetween, and the laminated body is integrally sintered with the resistive film, thereby forming a sintered body. Will be done.

[0008]

According to the resistor of the present invention, the resistance film is embedded inside the sintered body, and the periphery of the resistance film is covered with ceramics. It is possible to avoid variations in characteristics due to changes in resistance value, solve problems due to pinholes, and improve environment resistance against humidity and the like. Further, in the above sintered body,
Since a ceramic material made by adding a predetermined amount of zinc borosilicate glass or the like to ZnO is used, the adhesiveness between the sintered body and the resistance film can be improved, and the periphery of the resistance film is surrounded by the sintered body of the same material. Therefore, heat dissipation can be improved, and distortion due to a difference in thermal expansion can be reduced, so that a larger power capacity can be obtained.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. 1 and 2 are views for explaining a resistor according to an embodiment of the present invention. In the figure, 1 is a cermet resistor of this embodiment. The resistor 1 is formed by embedding a resistance film 4 made of Ru oxide or a compound thereof inside a substantially rectangular parallelepiped ceramics sintered body 3. The left and right end surfaces 4a and 4b of the resistance film 4 are exposed on the left and right side surfaces 3a and 3b of the sintered body 3, and the other remaining end surfaces are the sintered body 3
It is enclosed inside. Further, the left and right side surfaces 3a, 3b of the sintered body 3 are coated with external electrodes 5 made of Ag-Pd, and the external electrodes 5 are formed on the end surfaces 4 of the resistance film 4.
It is electrically connected to a and 4b.

The sintered body 3 is formed by laminating a plurality of ceramic sheets 2 to form a laminated body and integrally sintering the laminated body. In this case, the resistance film 4 is patterned on the upper surface of one ceramic sheet 2 located at the center in the thickness direction, and the remaining ceramic sheets 2 are formed on the ceramic sheet 2 on which the resistance film 4 is formed.
Are stacked like a sandwich.

The sintered body 3 is made of a ceramic material containing ZnO powder as a main component, and zinc borosilicate glass powder or lead zinc borosilicate glass powder as an auxiliary component added thereto. The total amount of the above glass powder added is within the range of 0.1 to 10% by weight.

Next, the function and effect of this embodiment will be described. According to the resistor 1 of this embodiment, the sintered body 3 and the resistive film 4 are provided.
Since the surroundings of the resistance film 4 are covered with ceramics, the conventional glass coating can be dispensed with, and the variation of the characteristics due to the change of the resistance value can be avoided. Further, since the problem of pinholes can be solved, the environment resistance against humidity and the like can be improved and the life characteristics can be improved.

Further, since a ceramic material containing ZnO as a main component and zinc borosilicate glass added to the sintered body 3 is adopted, the sintering temperature can be lowered, and the resistance obtained by this can be obtained. The film 4 has good adhesion to the sintered body 3,
Moreover, since the periphery of the resistance film 4 is surrounded by the ceramic material, heat dissipation can be improved, and distortion due to the difference in coefficient of thermal expansion can be reduced, so that the power capacity can be improved accordingly.
By the way, in contrast to the conventional resistance element having a power consumption of about 100 mW, the resistance element 1 of the present embodiment can obtain a power capacity of 10 times or more while achieving downsizing as compared with the volume of the conventional element.

Further, in the present embodiment, since the step of baking the conventional glass paste after applying it can be eliminated, the manufacturing cost can be reduced accordingly. Furthermore, since a plurality of resistance films 4 can be laminated, various resistors having different resistance values in the same pattern and the same process can be freely designed, and the application can be expanded.

Next, a method of manufacturing the resistor according to this embodiment will be described.
Explain. First, ZnO powder and zinc borosilicate glass
Powder or lead zinc borosilicate glass powder blended
Create a mix material. The composition ratio of this glass powder is Pb
₂O ₃, B₂O₃, SiO₂Of 0.1 to 10 wt%
So that it is added. Add pure water to the ceramic powder and add
Mill to form a slurry.

Next, the slurry is evaporated to dryness and
Preliminary calcination at 0 ° C. for 2 hours. This pre-baked product is roughly crushed, pure water is added to it, and finely crushed with a ball mill to form a ceramics raw material. Next, a solvent in which ethyl alcohol and toluene are mixed at a ratio of 6: 4 is added to this raw material and mixed by a ball mill to form a slurry.

A 70 μm thick green sheet is formed from the slurry by the doctor blade method, and the green sheet is dried and then cut into a predetermined size to form a large number of rectangular ceramic sheets 2.

Next, RuO ₂ : Ru ₂ Pb ₂ O ₇ : Ru
_A resistance paste is formed by adding a vehicle to a composition prepared by mixing ₂ Bi ₂ O ₇ = 6: 2: 2 mol. This resistance paste is printed on the upper surface of the one ceramic sheet 2 to form the resistance film 4. In this case, the left and right end surfaces 4a and 4b of the resistance film 4 are located at the left and right outer edges of the ceramic sheet 2, and the remaining other end surfaces are located inside the sheet 2.

Next, a plurality of ceramic sheets 2 are superposed and laminated on the upper surface and the lower surface of the ceramic sheet 2 on which the resistance film 4 is formed, and a pressure of ² t / cm ² is applied to the ceramic sheet 2 for pressure bonding. To form a laminated body. Next, this laminated body was cut into a predetermined size, heated to 400 ° C. to scatter the binder, and then heated to 920 ° C. and baked for 3 hours, whereby sintered body 3 was obtained. obtain. The sintered body 3 thus obtained is barrel-polished.

The left and right side surfaces 3a of the sintered body 3 are
3b is coated with an electrode paste having a ratio of Ag: Pd = 7: 3wt and baked at 850 ° C. for 10 minutes to form the external electrode 5, and the external electrode 5 and the left and right end faces 4a, 4 of the resistance film 4 are formed.
b is electrically connected. As a result, the resistor 1 of this embodiment is manufactured.

[0021]

[Table 1]

[0022]

[Table 2]

Next, a test carried out to confirm the effect of the resistor 1 of this embodiment will be described. This test is shown in Table 1.
And, as shown in Table 2, the addition amount of the above glass powder is 0.1
A large number of samples NO. 1 to NO. 24 were prepared by the above-mentioned manufacturing method while varying in the range of up to 50.0 wt%, and the resistance value (Ω), 3 CV (3σ / average × 100%), and power of each sample were prepared. The capacity (mW) was measured. In the table, * marks indicate outside the scope of claims of the present invention.

As is clear from Tables 1 and 2, sample Nos. 8, 9, and 2 in which the amount of glass powder added exceeded 10 wt%.
At 0 and 21, the variation of the resistance value is as large as 33 to 53%,
Moreover, the power capacity is reduced to 110 to 684 mW, and the characteristics are deteriorated due to the reaction between the sintered body and the resistance film. On the other hand, each sample No. 1 to 7, N whose addition amount is within the range of the present invention
In the case of O. 10 to 19 and NO. 22 to 24, it is found that the variation of the resistance value of each sample is as small as 5 to 21%, and the power capacity is significantly improved to 1140 to 1440 mW. .

[0025]

As described above, according to the resistor of the present invention, the resistance film is embedded in the inside of the sintered body, and Z is added to the sintered body.
Since a ceramic material containing nO as a main component and containing 0.1 to 10 wt% of zinc borosilicate glass and lead zinc borosilicate glass is used, it is possible to reduce variations in resistance value and to obtain environmental resistance characteristics against humidity and the like. This has the effect of improving the power capacity and life characteristics.

[Brief description of drawings]

FIG. 1 is a cross-sectional view illustrating a resistor according to an exemplary embodiment of the present invention.

FIG. 2 is an exploded perspective view showing the method of manufacturing the resistor according to the above-described embodiment.

[Explanation of symbols]

 1 Resistor 3 Sintered body 4 Resistive film

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tominaga Toru, Nagaokakyo City, Kyoto Prefecture 2 26-10 Ten shares, Murata Manufacturing Co., Ltd. Murata Manufacturing Co., Ltd.

Claims (1)

[Claims] 1. At least one inside the ceramic sintered body.
Two resistance films are embedded, and the sintered body is ZnO.
A resistor containing, as a main component, one or both of a zinc borosilicate glass and a lead zinc borosilicate glass as a subcomponent in a total amount of 0.1 to 10% by weight.