JPH02244601A - Resistor and manufacture thereof - Google Patents

Abstract

PURPOSE:To reduce the irregularity of resistance value and also to lessen the temperature dependency of the title resistor by providing a resistive layer consisting of a metal of resistive component element or its oxide or both of them which are inserted into the gap located between the matrix of glass and the atomic bond of the matrix. CONSTITUTION:A resistor, containing opposed conductive electrodes 2 and 2, a resistive layer 3 which makes contact with the electrodes 2 and 2, or a substrate 1 at least having an insulative surface and supporting the electrodes 2 and 2 and the resistor layer 3, is provided. This resistor is composed of the metal of a resistive component element, having the resistive layer 3 entered into the gap of a glass matrix and the atomic bond of the matrix, or its oxide or both of them. The paste of borosilicate glass frit is printed on the resistive layer 3, sintered and a protective layer 4 is formed. As a result, a resistor having small irregularity, low temperature dependency and excellent productivity can be formed.

Description

[Detailed Description of the Invention] Industrial Field of Application The present invention relates to resistors suitable for miniaturization and higher performance of electronic equipment, such as fixed resistors, variable resistors, chip resistors, and hybrid circuit resistors, and a method for manufacturing the same. It is related to.

A conventional fixed resistor includes at least a pair of electrodes, a resistor layer in contact with both electrodes, and at least a surface of which is insulating.
It basically consists of a substrate supporting the electrode and resistor layer on its surface, and a protective layer formed on the resistor layer. Depending on how they are made, there are thin film types and thick film types. The thin film type is one in which the electrode, resistor layer, and wear-resistant layer are formed by sputtering, vapor deposition, etc. in a vacuum. Resistance materials used include tantalum nitride and tantalum metal. In addition, the thick film type is made by printing and baking a glass frit-based paste containing silver, a paste containing RuOa and glass frit, and a borosilicate glass frit paste, respectively, and then printing and firing them to create a glass in which silver electrodes and Rubs are dispersed. By obtaining a resistor layer made of a layer and a protective layer made of glass, a high-performance resistor can be obtained at a lower cost than a thin film type. Most of the discrete chip resistors currently produced belong to this category.

Problems to be Solved by the Invention Current resistors, especially resistors used in microelectronic circuits such as chip resistors, are required to: (1) have small variations in the individual resistance values of the resistors; , (2) low temperature dependence of resistance value, (3) excellent reliability, and (4) excellent mass productivity and low cost.

The above-mentioned thin film resistor can be obtained with excellent resistance value variation and temperature dependence of resistance value by specifying the resistance material. however,
There are problems with reliability such as pulse resistance and moisture resistance, and because it is a thin film process, it is disadvantageous in terms of mass production and cost.

-Thick blade model resistors are advantageous in terms of mass production, cost, reliability, etc., but require improvement in terms of resistance value variation of individual resistors, temperature dependence of resistance value, etc. These problems with thick film resistors are discussed in detail below.

The resistor layer of the thick film resistor is formed by screen printing a paste consisting of Ru02 as a resistor component, glass frit, and an organic binder on an insulating substrate, and then firing the paste. However, since the starting paste is a mixture of Ru0a powder and glass powder, the resulting resistor layer is also a mixture of the two. Even if Ruop powder with a small particle size is used, it may aggregate or have poor dispersion into the glass matrix, resulting in a considerably large particle size in the resulting resistor layer. As a result, current will flow through the RuO2 powders that are in contact with each other.

Therefore, in order to obtain a resistor with a -like resistance value,
A considerable amount of Ru 02 powder is required.

Currently, such variations in resistance values of individual resistors are reduced by cutting and trimming the resistor layer, such as laser cutting after forming the resistor layer.
The resistance value variation of a 100-element resistor on a substrate with a size of 50 nm can be ±1%. However, there is a problem in that the trimmed resistance value changes due to thermal effects during the first layer printing and firing process after laser trimming, and the resistance value variation in the final product resistor increases to ±5%. .

In addition, a so-called current overload trimming method has been proposed in which the resistance value is changed by applying an electric pulse to the resistor layer after forming the protective layer, but the conventional resistor layer is
Due to the uneven distribution of 2O3, the resistance value changes preferentially in parts of the resistance layer that are particularly easy to trim, so even if the resistance value reaches the target value, it is difficult to obtain a highly reliable resistor.

On the other hand, the temperature dependence of the resistance value is dominated by the temperature change in the resistance value of RuO2, and a conventional resistor made of a mixture of glass and Rubs exhibits a large positive characteristic.

As described above, with the conventional method of forming a resistor layer from a mixture of Ruot and glass powder, it is difficult to obtain a resistor layer with a negative resistance value.

Means for Solving the Problems In order to solve the above-mentioned disadvantages of conventional resistors, the present invention provides at least one pair of electrodes, a resistor layer in contact with the picture electrode, and at least a surface of which is insulating. In a resistor comprising a substrate supporting the electrode and the resistor layer on its surface, the resistor layer enters the gap between the glass matrix and the IJ glass atomic bond. It is characterized in that it is composed of a metal as a resistor component element, an oxide thereof, or both. Alternatively, ruthenium oxide may be dispersed mainly at the molecular level in the glass matrix.

According to the present invention, it is possible to obtain a resistor with high productivity, which has small variations in resistance value, small temperature dependence of resistance value, and excellent reliability.

EXAMPLES Before showing specific examples of the present invention, the resistive material used in the present invention and the method for forming the resistor layer will be explained in detail.

A preferred method for obtaining the resistor layer of the resistor of the present invention is to form a coating of a paste containing a pyrolyzable organic compound as a resistor component element and a pyrolyzable organic compound as an element forming a glass matrix. A process of forming by printing, spin footing, drawing method, etc., thermally decomposing the organic compound in the paste by heat treatment to form a glass matrix, and a metal of a resistor component element dispersed in the matrix, an oxide thereof, or both. and a step of generating a resistor layer consisting of.

The paste is preferably composed of the organic compound, a solvent that dissolves the organic compound, and an organic binder that is soluble in the solvent.

In this paste, organic compounds of resistor component elements,
Oxides of the elements that form the glass matrix are mixed at the molecular level with organic compounds that form the glass matrix by thermal decomposition, metals of the resistor component elements, their oxides, or both. is generated,
The latter metal, its oxide, or both are then incorporated into the glass matrix produced by the fusion of the oxides to form a resistor layer. In the resistor layer produced in this way, the metal of the resistor component element, its oxide, or both are in a state of entering into the gaps between the atomic bonds of the glass matrix at the atomic or molecular level. Therefore, the resistor layer has a very uniform composition, and the amount of resistor component elements may be smaller than conventional ones.

Figure 3 shows the relationship between the ruthenium element content of a resistor layer consisting of a glass matrix and mainly ruthenium oxides dispersed in the matrix and the variation in the resistance value of the resistor layer. . However, this result is 50
10 on alumina substrate with mrrxX50mrn size
This is the variation in the individual resistance values of a resistor chip with 0 elements. Note that the vertical axis related to the resistance value shows σ/R, vX10
a representing a value of 0 RPV is the average value of the resistance value, and σ is the standard deviation value.

In FIG. 3, A represents the characteristics of the resistor layer obtained by the method of the present invention, and B represents the characteristics of the resistor layer obtained by the conventional method. In case A, the particle size of the ruthenium oxide is 1 μm or less, and in case B, the particle size is 5 μm or more.

In the case of B, when the ruthenium element content is less than 10% by weight, the resistance value suddenly fluctuates widely and becomes null. On the other hand, A
In the case of , the variation in resistance value is very low even if the ruthenium element content is small.

Another method for obtaining the resistor layer is to use a paste containing a thermally decomposable organic compound as a resistor component element and glass frit instead of the paste. In this case as well, the paste preferably contains a solvent that dissolves the organic compound and an organic binder that is soluble in this solvent. When this paste is used, the dispersibility of the resistor component element metal and/or its oxide in the resulting resistor layer is inferior to that of the above method, but is much better than that of the conventional method. ing. That is, the organic compound is in contact with the glass frit particles in a solution state in the paste, and the metal, its oxide, or both produced by thermal decomposition are dispersed on the surface of the glass frit particles at the molecular level, and their state It is incorporated into the glass matrix formed by the fusion of glass frits.

Here, the resistor component elements applicable to the present invention include ruthenium, gold, silver, nickel, chromium, tantalum, etc., and ruthenium is particularly preferred. Ruthenium exists primarily as an oxide in the resistor layer. In the resistor layer using ruthenium, the temperature dependence of the resistance value is very large as shown in a in FIG. 4. To improve this, it is better to use rhodium in combination. By using rhodium in combination, the temperature dependence of the resistance value is improved as shown in FIG. 4b.

Furthermore, the addition of rhodium also improves the film formability of the resistor layer. When ruthenium and rhodium are used together, the appropriate weight ratio is O<Rh/Ru<5.

Next, elements that form the matrix of glass include boron and silicon that make up borosilicate glass, lead that makes up lead borosilicate glass, lanthanum that makes up lanthanum-based glass, and bismuth. .

In addition to the above, zirconium, titanium,
Vanadium, aluminum, tantalum, zinc, etc. may also be added.

Thermal decomposable organic compounds of the above elements include alcoholades such as ethyl alkoxide and isopropoxide, fatty acid esters such as hexanoate esters, polycyclic organic compounds such as menthol alcoholades and esters, and rosins such as abietate. compounds, siloxanes, boric acid organic compounds, etc.

The temperature at which a paste containing these organic compounds is heated to produce a desired metal or oxide varies depending on the compound used, but is usually 500 to 800'C, preferably in an atmosphere containing oxygen.

In the above, a thermally decomposable organic compound was used, but it is also possible to use a compound that is excited by ultraviolet irradiation and gives a metal or its oxide, or both, such as a ruthenium salt of a naphthoquinone diazo compound having a carboxyl group, or a novolac-based phenolic resin compound. Examples include compounds with lead, silicon, or bismuth.

When using these compounds, the paste coating is irradiated with ultraviolet light to decompose it.

According to the invention, 0. A resistor layer with a uniform thickness of 3 to 3 μm can be obtained. This resistor layer is thin,
In addition, since there are almost no defects such as bubbles, the resistance value variation is small and the reliability is high.

Next, specific embodiments of the present invention will be shown according to the drawings.

Example 1 As shown in Fig. 1, thickness OJmm, 50+nmX
On a 50 mm alumina substrate 1 (purity 97%), -
The pattern of the group of opposing conductive electrodes 2 is formed by printing and firing (810° C.) a silver-glass frit type paste. A resistor paste is screen-printed between the opposed groove N electrodes 2 in contact with the picture electrode, and fired to form the resistor layer 3. The paste for resistors is Rut Rh.

Sit B, viscosity 500 made from Pb hexanoate, ethyl cellulose and terpineol.
00 cp was used. After printing the paste, it was left to dry and then fired at 800''C to form the resistor layer 3.

A borosilicate glass frit paste was printed on the resistor layer 3 and fired to form a protective layer 4. The mixing ratio of hexanoate in the resistor paste is Ru:Rh
:Si:B:Pb weight ratio: 10:4:
The ratio was set to 14:4:68. Next, it is separated into individual chips, and finally the current collecting electrode 5 is placed in contact with the conductive electrode 2.
was formed using silver paste.

Example 2 Ruthenium octanoate, ruthenium ethyl alkoxide, Pb, and ethyl alcoholade of Sit B were prepared in a weight ratio of Ru: Pb: Si: B:
The paste was mixed in a ratio of 70:15:7, ethyl cellulose and terpineol were added thereto, and a paste was printed and fired to form a resistor layer. The rest is the same as in Example 1.

Example 3 As shown in FIG. 2(a), the same resistor paste coating as in Example 1 was applied to the steel plate +1 having the hollow coating layer IO using a roll coater, and the resistor was baked at 800'C to form a resistor. Layer 12 was used. Next, as shown in FIG. 2(b), a group of opposing groove N electrodes 13 were formed on the resistor layer 12 by printing and firing a paste consisting of gold ethyl mercaptide, ethyl cellulose, and terpineol. . A protective layer I5 was formed by printing and baking the paste, leaving the electrode margin part 14. The paste used here is S L
It is composed of each hexanoate of Brpb, ethyl cellulose, and terpineol. Finally, place the silver paste electrode B1 in contact with the electrode margin part 14.
6 was formed. Finally, as shown in FIG. 2(e), individual chips were cut and separated.

Example 4 After forming a film by printing a paste consisting of a ruthenium salt of a naphthoquinodiazo compound having a carboxyl group, a compound of a novolac-based phenolic resin compound and lead, silicon, and boron, ethyl cellulose, and terpineol, a ruthenium/glass-based film was formed by UV irradiation. form a resistor film.

The rest is the same as in Example 1.

Example 5 The resistor paste was the same as Example 1 except that a mixture of ruthenium hexanoate and borosilicate glass frit in a weight ratio of 1:10, to which ethyl cellulose and terpineol were added, was used.

Example 6 The resistor paste was the same as Example 1 except that a paste consisting of ethyl mercapboude of gold, diphenylsiloxane, a menthol compound of boron, ethyl cellulose, and terpineol was used. However, the mixing ratio of organic compounds in the paste is gold: (S i +
The coulometric ratio of B) was set to 0.15:1.

Comparative Example 1 A group of electrode layers is formed on an alumina substrate by printing and firing a glass frit-silver thread paste.

A resistor paste is printed and fired in contact with each electrode to form a resistor layer. A protective layer is formed on the resistor layer by printing and baking a borosilicate glass frit paste. The resistance paste used at this time had an average particle size of 0.1 μm and a maximum particle size of 0.
．． Ethyl cellulose and terpineol were added to a mixture of 40% by weight of 8 μm ruthenium oxide powder and 60% by weight of borosilicate glass frit. The printed paste film was fired at 800°C.

Comparative Example 2 The resistor of Comparative Example 1 was subjected to overload trimming by applying a pulse of 2 W/piece.

Comparative Example 3 A film with a thickness of 30 mm was formed by sputtering on an alumina substrate.
A tantalum nitride film of 0 (IA) was formed. After etching with hydrofluoric acid, copper and chromium electrodes were formed by vapor deposition.

The characteristics of the resistors of each of the above examples and comparative examples are shown in the following table.

However, the variation in resistance value is the value for 100 chip resistor elements formed on a 50 mm x 50+ nm alumina sheet. Reliability is indicated by the rate of change (%) in resistance value after 1000 hours in an atmosphere of 85° C. and 90% RH.

Effects of the Invention As described above, the present invention combines the advantages of conventional thin-film resistors and thick-film resistors, that is, has small variations in resistance value, low temperature dependence, and excellent reliability. , resistors with excellent productivity can be obtained.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a resistor in one embodiment of the present invention, FIGS. 2(a) to (C) are cross-sectional views showing the manufacturing process of a resistor in another embodiment of the present invention, and FIG. A diagram showing the relationship between the ruthenium content of a resistor layer containing ruthenium as a resistor component and the variation in the resistance value of the resistor layer. Figure 4 also shows the temperature dependence of the resistance value of the resistor layer containing ruthenium. It is a diagram. 1... Alumina substrate, 2... Opposing conductive electrode, 3...
・Resistor layer, 4... Protective layer, 5... Current collecting electrode, 10
... Hollow coating layer, 11... Copper plate, 12... Resistor layer, 13... Opposing conductive electrode, 15... Protective layer, 1
8... Silver paste electrode layer. Name of agent: Patent attorney Shigetaka Awano and 1 other person Figure 1/-11 Alumina Basics Against? 1 opposing conductor 1 color electrode - 3 - 11 o disorder resistance main layer 4 - - Iku Ikugari (A 106 - collection of electricity 1 10 - 1 - hollow covered 1 layer ff - 1 Zenmachi board l? - Challenging body layer l total pair 1"f list electrode is - Ichibo eruption layer lθ 15 F? Sinna Kiyo quantity C bullet

Claims (13)

[Claims] (1) Constituent elements include at least one pair of electrodes, a resistor layer in contact with both of the electrodes, and a substrate having at least an insulating surface and supporting the electrodes and the resistor layer on the surface. A resistor, wherein the resistor layer is composed of a glass matrix and a metal of a resistor component element, an oxide thereof, or both, which are inserted into the atomic bond gaps of the matrix. vessel. (2) The resistor according to claim 1, wherein the resistor component element is ruthenium and is mainly dispersed as an oxide in the glass matrix. (3) The resistor according to claim 1, further comprising rhodium as a resistor component element. (4) Ruthenium contained in the resistor layer is 10% by weight
4. The resistor according to claim 2, wherein the resistor is less than 10%. (5) The resistor according to claim 1, wherein the resistor component element is selected from the group consisting of gold, silver, nickel, chromium, and tantalum. (6) The resistor according to claim 1, wherein the glass forming the resistor layer is borosilicate glass or lead borosilicate glass. (7) The resistor according to claim 1, wherein the glass forming the resistor layer is lanthanum glass. (8) A resistor comprising at least one pair of electrodes, a resistor layer in contact with both electrodes, and a substrate having at least an insulating surface and supporting the electrodes and the resistor layer on the surface. , wherein the resistor layer is composed of a glass matrix and ruthenium oxide dispersed in the matrix primarily at the molecular level. (9) The resistor according to claim 8, wherein rhodium or its oxide is further dispersed at the atomic or molecular level in the matrix. (10) The resistor according to claim 8, wherein the matrix is borosilicate glass or lead borosilicate glass. (11) The resistor according to claim 8, wherein the resistor component element is selected from the group consisting of gold, silver, nickel, chromium, and tantalum. (12) At least one pair of electrodes, a resistor layer in contact with both electrodes, and at least a surface are insulating,
In the method for manufacturing a resistor including a substrate supporting the electrode and the resistor layer on the surface thereof, the step of forming the resistor layer includes the step of forming the resistor layer using a thermally decomposable organic compound and glass as resistor component elements. A step of forming a paste film containing a thermally decomposable organic compound of an element forming a matrix on the substrate before or after forming the electrode, and thermally decomposing the organic compound in the paste by heat treatment. 1. A method for manufacturing a resistor, comprising the steps of: producing a resistor layer comprising a glass matrix and a metal of a resistor component element, an oxide thereof, or both dispersed in the matrix. (13) At least one pair of electrodes, a resistor layer in contact with both electrodes, and at least a surface thereof are insulating,
In the method for manufacturing a resistor including a substrate supporting the electrode and the resistor layer on the surface thereof, the step of forming the resistor layer comprises using an ultraviolet decomposable organic compound and glass as resistor component elements. forming a paste coating on the substrate before or after forming the electrode, comprising an ultraviolet decomposable organic compound of an element forming a matrix;
A step of decomposing the organic compound in the paste by irradiating ultraviolet rays to produce a resistor layer consisting of a glass matrix and a resistor component element metal or its oxide or both dispersed in the matrix. A method for manufacturing a resistor characterized by: