JPH04139802A - Resistor and its manufacture - Google Patents

Abstract

PURPOSE:To obtain a resistor excellent in noise characteristics in a high- resistance region by dissolving four specific compounds in an organic solvent to be applied on an insulating substrate and by baking it. CONSTITUTION:Compounds which contain lead or bismuth, ruthenium, silicon, and alkali metal or alkali soil metal, respectively, are dissolved in an organic solvent, applied on an insulating substrate 11, and baked to form a resistor 14. That is, alkali metal or alkali earth metal of high anionicity is distributed in a form to hold local electric neutrality in a network structure formed by silicon oxide as anions, and lead and bismuth of low anionicity do not mix in this network structure, but react with ruthenium to produce a complex oxide which forms a cubic pyrochlore type. This allows manufacture of a resistor 14 excellent in noise characteristics in a high-resistance region.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a resistor used in various electronic devices and a method for manufacturing the resistor.

BACKGROUND OF THE INVENTION Ruthenium oxide and its compounds are chemically stable, and resistors containing it as a main component in the conductive component are widely used. A square plate type fixed chip resistor, which is an example of a component using ruthenium oxide, has a structure as shown in FIG. 1 is an insulating substrate, 2 is an electrode, 3 is a resistor formed between the electrodes 2, and 4 is a protective glass that covers the resistor 3. The structure of the resistor 2 is as shown in FIG.
That is, ruthenium oxide is arranged in a three-dimensional network in a matrix of insulating particles 5 such as glass,
The resistance value is determined by changing the ratio of these two. This resistor can be manufactured at low cost by printing and firing, but since it has a complicated structure as described above, it is required to increase the volume fraction of the insulating particles 5 in the high resistance region, that is, 10 kohm/sq.
Above, the noise characteristics are 0 to +20 dB, which is inferior to thin film resistors such as metal films, and there is still room for improvement.

In order to improve the noise characteristics of a resistor, it is necessary to increase the conductive component in the structure.For conventional ruthenium oxide-based resistor materials, insulating materials such as glass are used to adjust the resistance value and improve adhesion to the substrate. is essential. Recently, it has been discovered that a resistor with good noise characteristics can be obtained by forming a mixture of metal oxides on an insulating substrate by thermal decomposition of a metal compound.

Problems to be Solved by the Invention However, as a conductive material, a mixture of a composite oxide of lead and ruthenium or a composite oxide of bismuth and ruthenium, which has a high specific resistance value, and an oxide of silicon, which increases the resistance value, is used. Therefore, when each of the metal compounds mentioned above is coated on an insulating substrate and fired, no composite oxide, which is a reaction product of lead and ruthenium, or bismuth and ruthenium, is produced.
The problem was that ruthenium oxide with a low specific resistance value was formed. This is because lead and bismuth are highly cationic and enter as cations into the irregular network structure formed by silicon oxide, so lead and ruthenium and bismuth and ruthenium do not react.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for manufacturing a resistor that eliminates the above-mentioned conventional drawbacks and dramatically improves the noise characteristics of the resistor in a high resistance region.

Means for Solving the Problems To achieve this object, the present invention provides a compound containing lead or bismuth in its structure, a compound containing ruthenium, a compound containing silicon, and an alkali metal or alkaline earth compound. A solution of a metal-containing compound dissolved in an organic solvent is applied onto an insulating substrate and fired to form a lead-ruthenium composite compound or a bismuth-ruthenium composite oxide, a silicon oxide, an alkali metal or This is characterized by forming a resistor made of an oxide of an alkaline earth metal.

According to the structure of the present invention, highly cationic alkali metals or alkaline earth metals are distributed as cations in the network structure formed by silicon oxide in a form that maintains local electrical neutrality. Lead and bismuth, which are less cationic than these alkali metals or alkaline earth metals, react with ruthenium without being mixed into this network structure, producing a cubic pyrochlore-type complex oxide.

Therefore, almost all of the constituent particles of the resistor can be made of lead or a complex oxide of bismuth and ruthenium, which have a high specific resistance value, as conductive materials, making it possible to manufacture resistors with excellent noise characteristics even in the high resistance range. be able to.

EXAMPLE A method of manufacturing a resistor according to an example of the present invention will be described below.

(Example I) For each paste No. 1 to 20 shown in Table 1, metal compounds 1 to 4 were mixed in the indicated composition ratio, and a total of 110 g was mixed and dissolved in 100 g of 4-methyl 2-pentanone. The coating liquid had a viscosity of 0.5 Pa-s.

(Margin below) Table 1 (Displayed value: m01%) For each sample, this coating solution was spin-coded onto a barium borosilicate glass (#7059 manufactured by Corning) substrate at a rotation speed of 2000 rpm, and dried. Thereafter, it was thermally decomposed in an electric furnace in the atmosphere and fired to form a resistor. The firing temperature at this time was 700°C. Table 2 shows the sheet resistance values of the resistors thus obtained.

(Margin below) Table 2 The sheet resistance value of the resistor can be changed by changing the firing temperature; when it is lowered, the resistance value decreases, and when it is raised, the resistance value increases. Furthermore, the film thickness of the obtained resistor changes depending on the viscosity of the metal compound in the coating liquid and the rotation speed of the spin cord, and the sheet resistance value changes accordingly.

As described above, the resistor of the present invention can achieve a wide range of resistance values by adjusting the chemical composition, film thickness, and processing temperature. Although the resistor was formed by coating the resistor on the substrate at a constant rotational speed and at a constant firing temperature, the desired resistance value can be obtained by appropriately selecting the above conditions.

In addition, the crystal structure of the resistor was investigated by X-ray diffraction. It is a cubic pyrochlore type in all compositions when the firing temperature is 500°C or higher, and there is no change in the diffraction peak intensity of X-ray diffraction even if the firing temperature is changed, so it is a stable substance against heat. It became clear that

These sample Nos. 1 to 20 of the substrates on which the resistors were formed were cut into strips with a width of 0.8 mm using a diamond cutter, and electrodes with a thickness of 1 μm or less were formed using commercially available gold paste. A resistor having a resistor size of .8 mm x 0.8 mm was manufactured. Furthermore, a protective glass layer is provided by coating and baking a commercially available glass paste on the surface of the resistor, and the gold electrode is nickel plated and soldered to reduce the current noise of these resistors. (Quan-Tech) The noise was measured using a current noise measuring device manufactured by the company. The applied voltage at this time was a voltage calculated assuming that the rated power of the resistor was 0.25W. The results are shown in Table 2.

As is clear from Table 2, at least as the resistance value decreases, the current noise also decreases, and when compared with the composition shown in Table 1, it is clear that the noise characteristics are mainly affected by the silicon content. It became.

As described above, from the results of this example, it was found that the resistor of the present invention has very excellent noise characteristics even in a high resistance region.

(Example 2) Next, another embodiment of the present invention will be described.

As in Example 1, the metal compounds shown in Table 1 were mixed in the indicated composition ratio, and a total of 5 g was added to 100 g of α-terpineol.
and add 100 g of dimerized rosin to this solution,
The dimerized rosin was dissolved by heating under reflux at a temperature of 100°C or more to prepare a paste.

Fig. 1 shows a square plate type chip fixed resistor manufactured according to the present invention, and Fig. 2 shows an enlarged view of the resistor portion thereof. In the figure, 11 is an insulating substrate, 12 is a base glass, 13 is a pair of electrodes, 14 is a resistor, 15 is a protective glass, and 16 is a conductive particle. The method for manufacturing this square plate type fixed chip resistor will be described below. On an insulating substrate 11 such as a 96% alumina substrate provided with slits for division, a glass paste with a softening point of 650°C is screen printed as a base glass 12, and after baking at 900°C, silver is printed as an electrode 13. - Each of the sample pastes Nα1 to 20 described above is screen printed on both ends of the base glass 12 using a similar method, dried, and then thermally decomposed and fired at 700°C in the atmosphere to form the resistor 14. Furthermore, a protective glass layer 15 was formed on the upper surface of this resistor 14 by printing and baking, and finally it was divided and end face electrodes were baked to produce the square plate type fixed chip resistor of this example.

The same measurements as in Example 1 were carried out for each of these chip resistors, and the results of the sheet resistance value and current noise are shown in Table 3. The results showed that a resistor with a resistance value and current noise depending on the paste composition could be obtained.

(Leaving space below) Table 3 Note that in this example, only a square plate type chip resistor is described as an example of the use of a resistor, but the paste produced in this example can be used to create hybrid ICs, resistor y L work, R work etc.
It can be used for a C network, a resistor of various variable resistors, and a heating resistor of a thermal head, and these elements can have the same performance as the above-mentioned chip/7-tub fixed resistor.

The reason why the noise characteristics of the resistors manufactured in Examples 1 and 2 are good as described above is that the resistor 14 layer is almost composed only of the conductive particles 16, as shown in FIG.

Effects of the Invention As described above, according to the present invention, a composite oxide comprising a composite oxide of lead and ruthenium or a composite oxide of bismuth and ruthenium, an oxide of silicon, and an oxide of an alkali metal or an alkaline earth metal, By producing a resistor whose crystal phase is a cubic pyrochlore single phase, it is possible to create a resistor with superior noise characteristics in the high resistance region compared to conventional ruthenium oxide thick film resistors. The industrial effect is enormous.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a square plate type fixed chip resistor using a resistor according to an embodiment of the present invention, Fig. 2 is an enlarged cross-sectional view of the resistor part, and Fig. 3 is a conventional metal glaze system thickness. FIG. 4 is a cross-sectional view of the membrane chip resistor, and FIG. 4 is an enlarged cross-sectional view of the resistor portion thereof. 11... Insulating substrate, 12... Base glass, 13... Electrode, 14... Resistor, 1
5... Protective glass layer, 16... Conductive particles. Name of agent: Patent attorney Akira Okaji Baka 2 Meijou

Claims (3)

[Claims] (1) Insulating a solution in which a compound containing lead or bismuth, a compound containing ruthenium, a compound containing silicon, and a compound containing an alkali metal or alkaline earth metal are dissolved in an organic solvent. It is coated on a substrate and fired to form a resistor consisting of a composite oxide of lead and ruthenium or a composite oxide of bismuth and ruthenium, an oxide of silicon, and an oxide of an alkali metal or alkaline earth metal. A method for manufacturing a resistor, characterized by: (2) A composite oxide of lead and ruthenium or a composite oxide of bismuth and ruthenium obtained by the method for manufacturing a resistor according to claim 1, an oxide of silicon, and an oxide of an alkali metal or alkaline earth metal. A resistor consisting of. (3) The resistor according to claim 2, wherein the crystal phase of the resistor is a cubic pyrochlore single phase.