Composition for thick film resistor, paste for thick film resistor, and thick film resistor

Abstract

To provide a thick film resistor which has such a good electric property that it is small in current noise while having a desired resistance value, and which is substantially lead free.SOLUTION: A composition for a thick film resistor, a paste for the thick film resistor, and the thick film resistor are provided. The composition comprises: as a conductive component, at least one kind selected from ruthenium dioxide, calcium ruthenate, strontium ruthenate and barium ruthenate; a glass component including substantially no lead; and steatite of 3.0 mass% or more and 15.0 mass% or less.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a thick film resistor composition and a thick film resistor paste used to form thick film resistors in resistance components such as chip resistors and hybrid ICs, and to a thick film resistor formed using the composition and the thick film resistor paste. [Background technology]

[0002] Conventionally, resistive components among electronic components include thick-film resistors formed using resistive paste, and thin-film resistors formed by sputtering a film-forming material, etc. Of these, thick-film resistors are widely used as resistive components for chip resistors, hybrid ICs, etc., because the manufacturing equipment is inexpensive and the productivity is high.

[0003] The thick-film resistor is formed by printing a paste for a thick-film resistor on a ceramic substrate and firing the paste. The paste for a thick-film resistor is essentially composed of a conductive powder, a glass frit, and an organic vehicle for making the conductive powder, glass frit, and glass frit into a paste suitable for printing.

[0004] Conductive powders include ruthenium dioxide (RuO2) and pyrochlore-type ruthenium oxide (Pb2Ru2O 7-X Ruthenium (Ru) compounds such as Bi2Ru2O7) are commonly used. The reason why ruthenium compounds are used as conductive powders is mainly because they have the characteristic that their resistance changes gradually with changes in their concentration.

[0005] Lead borosilicate glass containing a large amount of lead, such as lead borosilicate glass (PbO-SiO2-B2O3) and lead aluminoborosilicate glass (PbO-SiO2-B2O3-Al2O3), is used as the glass frit. Lead borosilicate glass is used for the glass frit because it has good wettability with ruthenium oxides, its thermal expansion coefficient is close to that of the substrate, and it is suitable in terms of viscosity during firing.

[0006] In these pastes for thick-film resistors, various additives are contained to improve the properties of the thick-film resistors after film formation. For example, titanium oxide (TiO2) or niobium oxide (Nb2O5) are conventional additives used to adjust the temperature coefficient of resistance (TCR) and reduce current noise. JP-A-61-206201 discloses a composition for thick-film resistors in which conductive powder, glass powder containing PbO, and titanium oxide are added in an amount of 0.025 to 6.0 parts by weight as Ti per 100 parts by weight of solid content in the composition. JP-B-63-035081 discloses a composition for thick-film resistors in which finely divided inorganic powders of RuO2, glass containing PbO, and Nb2O5 are dispersed in an inert liquid vehicle, and the amount of Nb2O5 added is 0.1 to 0.8% by weight.

[0007] The glass powder constituting these compositions for thick-film resistors contains lead. The use of pastes for thick-film resistors containing such harmful lead is undesirable from the viewpoint of environmental issues, and in recent years, there has been a strong demand for practical use of pastes for thick-film resistors that do not contain lead. For this reason, research and development of pastes for thick-film resistors that do not contain lead is currently being carried out, and a glass frit that does not contain lead has been proposed for compositions for thick-film resistors used in pastes for thick-film resistors. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Japanese Patent Application Publication No. 61-206201 [Patent Document 2] Special Publication No. 63-035081 Summary of the Invention [Problem to be solved by the invention]

[0009] In a thick-film resistor composition containing titanium oxide or niobium oxide as an additive, titanium oxide or niobium oxide is added as a powder to the thick-film resistor composition, or is added in advance to the glass powder constituting the thick-film resistor composition. However, when a lead-free thick-film resistor is produced using titanium oxide or niobium oxide as an additive, there is a problem that the current noise becomes large when the resistance value is set to 10 kΩ or more.

[0010] An object of the present invention is to provide a composition for a thick film resistor which, when a thick film resistor substantially free of lead is produced, can form a resistor having high resistance and low current noise and good electrical properties, and to provide a thick film resistor paste and a thick film resistor using this composition for a thick film resistor. [Means for solving the problem]

[0011] The thick-film resistor composition of the present invention is characterized in that it contains a conductive powder and a glass frit that is substantially free of lead, and contains 3.0% by mass to 15.0% by mass of steatite added, preferably 5.0% by mass to 14.0% by mass.

[0012] The content of the conductive powder is preferably 5% by mass or more and 30% by mass or less. The conductive powder is preferably made of a ruthenium compound. The ruthenium compound is preferably made of ruthenium dioxide and / or alkaline earth metal ruthenate.

[0013] The thick film resistor paste of the present invention contains a thick film resistor composition and an organic vehicle, and is characterized in that the thick film resistor composition of the present invention is used as the thick film resistor composition.

[0014] The content of the organic vehicle is preferably 30% by mass or more and 50% by mass or less based on the mass of the paste for thick film resistors.

[0015] The thick-film resistor of the present invention is made of a sintered body containing a conductive component, a glass component, and steatite, the glass component being substantially free of lead, and the conductive component and the glass component and the steatite The conductive component is preferably comprised of a ruthenium compound. The conductive component is preferably comprised of a ruthenium dioxide and / or an alkaline earth metal ruthenate. The conductive component is preferably comprised of a ruthenium compound. The conductive component is preferably comprised of a ruthenium dioxide and / or an alkaline earth metal ruthenate. The conductive component is preferably comprised of a ruthenium compound. The conductive component is preferably comprised of a ruthenium dioxide and / or an alkaline earth metal ruthenate. Effect of the Invention

[0016] The thick film resistor composition, thick film resistor paste, and thick film resistor of the present invention can exhibit excellent electrical properties, such as high resistance and low current noise, without containing harmful lead. Thick film resistor paste By replacing these materials, it will be possible to provide resistance components such as chip resistors and hybrid ICs that do not cause environmental pollution, and therefore the industrial value of this technology is extremely great. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] The thick film resistor composition of the present invention will be described below. Thick film resistor paste , and thick film resistors will be described in detail.

[0018] (1) Composition for thick film resistors The composition for a thick film resistor of the present invention is characterized by comprising conductive powder, glass frit, and steatite as main components.

[0019] [Conductive powder] The conductive powder constituting the thick-film resistor composition of the present invention is preferably a ruthenium compound. Examples of the ruthenium compound include ruthenium dioxide (RuO2), alkaline earth metal ruthenate, i.e., calcium ruthenate (CaRuO3), strontium ruthenate (SrRuO3), and barium ruthenate (BaRuO3). The thick-film resistor composition of the present invention preferably contains at least one selected from these as the ruthenium compound. These conductive powders can be obtained by known manufacturing methods.

[0020] Calcium ruthenate, strontium ruthenate, or barium ruthenate can be obtained by a dry method in which ruthenium dioxide powder is mechanically mixed with hydroxides or carbonates of calcium, strontium, or barium, heat-treated, and then pulverized. In order to obtain these powders with a small and uniform particle size, a process is adopted in which a solution containing ruthenium chloride and calcium chloride, strontium chloride, or barium chloride is added to an alkaline aqueous solution to cause precipitation, the precipitate is washed and dried, and then roasted at a temperature of about 600°C to 900°C.

[0021] The conductive powder has an average particle size of preferably 1.0 μm or less, more preferably 0.2 μm or less, as determined by the BET method, so that the conductive paths in the thick-film resistor obtained by firing become fine, and it becomes possible to appropriately suppress the variation in the resistance value and the magnitude of the current noise.

[0022] In the thick-film resistor composition of the present invention, the content of the conductive powder is appropriately adjusted according to the desired resistance value of the thick-film resistor to be obtained, and the type and particle size of the conductive powder and the glass frit. For example, when a resistor having a high resistance with an area resistance value of 5 kΩ or more is to be obtained, the content of the conductive powder is usually 5% by mass or more and 30% by mass or less.

[0023] [Glass frit] The glass frit constituting the composition for thick film resistor of the present invention is characterized by being substantially free of lead.

[0024] Here, "substantially free of lead" means that the lead content in the glass frit is below the regulated value of the RoHS Directive (0.1% by mass) or the lead content is below the detection limit using ordinary measuring equipment.

[0025] Other glass components in the glass frit constituting the thick-film resistor composition of the present invention are basically not limited. As the glass frit, aluminoborosilicate alkaline earth zinc glass (SiO2-B2O3-RO-ZnO-Al2O3: R is at least one selected from Ca, Sr, and Ba), borosilicate glass (SiO2-B2O3), aluminoborosilicate glass (SiO2-B2O3-Al2O3), or borosilicate alkaline earth glass (SiO2-B2O3-RO: R is at least one selected from Ca, Sr, and Ba) can be suitably used.

[0026] The average particle size of the glass frit constituting the thick-film resistor composition of the present invention is preferably 5 μm or less, more preferably 1 μm or more and 3 μm or less, in terms of D50 (median diameter) by laser diffraction particle size distribution measurement. If the particle size of the glass frit is fine, the conductive path in the thick-film resistor can be made fine, and therefore it is possible to suppress the variation in the resistance value and current noise of the thick-film resistor. In order to obtain glass frit with a desired average particle size, the melted and cooled glass frit may be pulverized using a known pulverization method such as a ball mill or a jet mill.

[0027] In the glass frit constituting the thick-film resistor composition of the present invention, the softening point of the glass is preferably in the range of 550° C. to 750° C., more preferably in the range of 600° C. to 700° C. If the softening point of the glass is lower than 550° C., the glass frit may melt too much when the paste for the thick-film resistor is fired to form a resistor, causing the resistor pattern to collapse. If the softening point of the glass is higher than 750° C., the glass frit becomes difficult to melt and the compatibility (wetting) with the conductive powder becomes poor, so that the current noise of the obtained thick-film resistor increases.

[0028] The softening point herein is a temperature at which the next differential thermal curve on the higher side decreases relative to the temperature at which the lowest differential thermal curve decreases when a glass is heated in air at a rate of 5°C / min to 20°C / min inclusive by differential thermal analysis.

[0029] In the glass frit constituting the thick film resistor composition of the present invention, the thermal expansion coefficient of the glass is 40×10 -7 / K or more 100×10 -7 / K or less, and 50×10 -7 / K or more 90×10 -7 / K or less. For example, when an alumina substrate is used, by using a glass frit made of glass having a thermal expansion coefficient in this range, the thermal expansion coefficient of the obtained thick-film resistor becomes close to that of the alumina substrate, and the problem of tensile stress is eliminated. The thermal expansion coefficient can be measured by molding the glass frit into a rod shape and using a thermomechanical analyzer (TMA).

[0030] The softening point and thermal expansion coefficient of the glass frit can be controlled by examining the composition of the glass frit.

[0031] The content of the glass frit in the composition for thick-film resistor is also appropriately adjusted according to the desired resistance value of the thick-film resistor to be obtained, and the type and particle size of the conductive powder and the glass frit. For example, when a resistor having a high resistance with an area resistance value of 5 kΩ or more is to be obtained, the content of the glass frit is usually 70% by mass or more and 95% by mass or less according to the content of the conductive powder.

[0032] [Steatite] The thick-film resistor composition of the present invention is characterized by containing steatite. Steatite is represented by the formula MgO·SiO2. Steatite exhibits excellent insulating properties even in high-temperature environments, has excellent high-frequency characteristics, and is also excellent in mechanical strength and oxidation resistance, and therefore has been conventionally used as a high-frequency insulator or an insulating terminal for communication devices. Steatite also has a large thermal expansion coefficient of 77×10 -7 / K.

[0033] The addition of steatite increases the resistance value of the thick film resistor and reduces current noise. Steatite has conductive particles that gather between glass particles and Firing process It works to reduce the aggregation caused by the melting and flow of glass that occurs in the glass. Steatite easily wets glass and has a large thermal expansion coefficient, which is thought to enhance this function.

[0034] The BET average particle size of the steatite powder constituting the thick film resistor composition of the present invention is preferably 2 μm or less, and more preferably 1 μm or less.

[0035] The content of steatite in the thick film resistor composition is 3.0 mass% or more and 15.0 mass% or less, and preferably 5.0 mass% or more and 14.0 mass% or less. If the content of steatite is 3.0 mass% or more, the effect of reducing current noise can be sufficiently exhibited. Also, if the content of steatite is 15.0 mass% or less, the current noise can be reduced without increasing the resistance value too much.

[0036] [Optional ingredients] In the thick-film resistor composition of the present invention, in addition to the conductive powder, glass frit, and steatite, other additives can be added. For example, for the purpose of adjusting the electrical properties such as sheet resistance and temperature coefficient of resistance, adjusting the expansion coefficient, improving voltage resistance, and other modifications in the thick-film resistor, the thick-film resistor composition of the present invention can appropriately contain inorganic components such as manganese dioxide, copper oxide, niobium pentoxide, tin oxide, tantalum oxide, and titanium oxide.

[0037] The content of these inorganic components is generally in the range of 0.05% by mass to 10% by mass with respect to the total mass of the conductive powder and the glass frit.

[0038] (2) Thick film resistor paste The thick-film resistor paste of the present invention contains a thick-film resistor composition and an organic vehicle, and is characterized in that the thick-film resistor composition of the present invention is used as the thick-film resistor composition. Specifically, the thick-film resistor paste of the present invention is composed of a kneaded product of the thick-film resistor composition of the present invention and an organic vehicle. Details are described below.

[0039] [Organic vehicle] The organic vehicle constituting the paste for the thick film resistor is composed of at least a resin and a solvent.

[0040] Resins that can be used as the organic vehicle include ethyl cellulose resin, butyral resin (polyvinyl butyral), acrylic resin, etc. These resins are preferably those that decompose at a temperature before the glass softens, and more preferably those that decompose at a temperature of 500°C or less.

[0041] As a solvent for dissolving the resin, terpineol, butyl carbitol, butyl carbitol acetate, etc. can be used.

[0042] The blending ratio of the resin and the solvent in the organic vehicle prepared from these resins and solvents can be appropriately adjusted depending on the desired viscosity and application.

[0043] In addition, in consideration of the continuous printability required for the thick film resistor paste, a plasticizer having a high boiling point can be further added from the viewpoint of controlling the drying speed of the paste. In this case, the compounding ratio of the plasticizer can also be appropriately adjusted according to the desired drying speed.

[0044] The ratio of the organic vehicle to the thick-film resistor paste is not particularly limited, but is generally 30% by mass or more and 50% by mass or less based on the mass of the thick-film resistor paste.

[0045] [Other ingredients] The paste for thick-film resistors of the present invention may contain additives in addition to the composition for thick-film resistors and the organic vehicle. For example, a dispersant may be contained from the viewpoint of preventing aggregation of conductive powders and other inorganic components. Furthermore, a rheology control agent may be contained from the viewpoint of coating workability.

[0046] [Preparation method of paste for thick film resistor] The thick-film resistor paste may be prepared by using known techniques, such as a three-roll mill or a ball mill.

[0047] In the thick film resistor paste, it is desirable to break down the agglomerates of the conductive powder, glass frit, steatite, and other inorganic components, and disperse them in the organic vehicle.

[0048] (3) Thick film resistor The thick film resistor of the present invention is composed of a sintered body containing a conductive component, a glass component, and steatite. The conductive component contains at least one selected from ruthenium compounds, i.e., ruthenium dioxide, calcium ruthenate, strontium ruthenate, and barium ruthenate. The glass component is characterized by being substantially free of lead. That is, the thick film resistor of the present invention is formed using the thick film resistor paste of the present invention and is composed of a sintered body containing the thick film resistor composition of the present invention.

[0049] Therefore, the conductive component has the same composition as the conductive powder constituting the thick-film resistor composition of the present invention, and the glass component has the same composition as the glass frit constituting the thick-film resistor composition of the present invention. Also, the content of steatite is the same as that of the conductive component and the glass component, as in the thick-film resistor composition of the present invention. and the steatite It is 3.0 mass % or more and 15.0 mass % or less, preferably 5.0 mass % or more and 14.0 mass % or less, based on the total mass of the conductive component, the glass component, and the steatite. Therefore, the explanation of the conductive component, the glass component, and the steatite will be omitted here.

[0050] A method for producing the thick film resistor will be described below. Note that the resistance value of the thick film resistor can be appropriately adjusted by adjusting the ratio of the conductive powder and the glass frit in the thick film resistor.

[0051] [Manufacturing method of thick film resistors] The method for producing a thick-film resistor of the present invention is not limited to the following, and the processing conditions and the like can be appropriately changed using known means and methods.

[0052] First, a coating process is performed in which a paste for thick film resistors is applied to a substrate. On ceramic substrate Electrodes made of silver (Ag), palladium (Pd) or the like are formed on the substrate, and the paste for thick-film resistor of the present invention is applied thereon by means of screen printing or the like.

[0053] Next, a firing process is performed to fire the substrate on which the thick-film resistor paste is applied, to produce a thick-film resistor. Specifically, in the application process, the thick-film resistor paste applied to the substrate is dried using an oven or the like, and then fired using a belt furnace or the like to obtain a fired body containing a conductive component and a glass component. Basically, all components other than those resulting from the conductive powder and glass frit contained in the thick-film resistor paste, i.e., the resin and solvent constituting the organic vehicle, and further, other organic additives, are decomposed through the firing process.

[0054] Through the steps described above, the thick film resistor of the present invention is obtained.

[0055] The thick-film resistor of the present invention is composed of at least a conductive component containing at least one selected from ruthenium dioxide, calcium ruthenate, strontium ruthenate, and barium ruthenate, a glass component substantially free of lead, and steatite, and thus provides a thick-film resistor that is free of lead and has good electrical properties such as high resistance and low current noise.

[0056] The thick film resistor of the present invention may contain, in addition to the conductive component and the glass component, inorganic components such as manganese dioxide, copper oxide, niobium pentoxide, tin oxide, tantalum oxide, and titanium oxide.

[0057] In the above, the present invention has been described mainly using specific embodiments, and the best configurations and methods for implementing the present invention have been disclosed. However, the present invention is not limited to these. A person skilled in the art can omit, add, change or modify the shape, material, quantity and other detailed configurations of the above-described embodiments without departing from the technical idea and scope of the purpose of the present invention, and these are also included in the scope of the present invention. EXAMPLES

[0058] The present invention will be described in more detail below with reference to examples and comparative examples, although the present invention is not limited to the following examples.

[0059] Example 1 [Preparation of composition for thick film resistor] [Conductive powder] Ruthenium dioxide (RuO2) was used as the conductive powder. Ruthenium dioxide was prepared by roasting ruthenium hydroxide in air at 800°C for 2 hours. The BET average particle size was 0.05 μm.

[0060] [Glass frit] The glass frit used had a composition of 10% by mass SrO-4, 3% by mass SiO2-16% by mass B2O3-4% by mass Al2O3-20% by mass ZnO-7% by mass Na2O. This glass frit was produced by the usual steps of mixing, melting, quenching, and pulverization. In the pulverization step, the glass frit was pulverized until its particle size reached 1.5 μm in D50 (median diameter) as measured by laser diffraction particle size distribution measurement.

[0061] [Steatite] Steatite was prepared by mixing forsterite (product name: FF-200-M40, average particle size 2.5 μm) manufactured by Marusu Glaze LLC with molten SiO2 powder, and roasting the mixture at 1100° C. The roasted product was pulverized to obtain a BET average particle size of steatite of 1.0 μm.

[0062] [Organic vehicle] The organic vehicle used was a solution of ethyl cellulose in terpineol, with a mixing ratio of ethyl cellulose:terpineol of 1:9.

[0063] [Preparation of paste for thick film resistors] The target thickness of the thick-film resistor after firing was set to 7 μm to 9 μm, and the sheet resistance to 10 kΩ (±20%), 33 kΩ (±20%), and 100 kΩ (±20%). In Examples 1 to 3 and Comparative Examples 1 to 3, 60 mass % of a composition for a thick-film resistor containing the above-mentioned conductive powder, glass frit, and steatite in proportions of 17.5 mass %, 77.5 mass %, and 5.0 mass % was mixed with 40 mass % of an organic vehicle, and the mixture was kneaded with a three-roll mill. Thick film resistor paste The composition of the thick film resistor was shown in Table 1.

[0064] [Making thick film resistors] The thick film resistor paste prepared as described above was applied by screen printing to an alumina substrate on which electrodes had been formed in advance using AgPd paste, to a width of 1 mm and a distance of 1 mm (1 mm x 1 mm) between the electrodes. The thick film resistor paste applied to the substrate was then dried in an oven at 150°C for 10 minutes, and then fired in a belt firing furnace under conditions of a peak temperature of 850°C, a peak time of 9 minutes, and a total firing time of 30 minutes, to produce a thick film resistor.

[0065] [Thick film resistor evaluation] In order to evaluate the electrical characteristics of the thick-film resistors, the sheet resistance and current noise were measured for each thick-film resistor as follows.

[0066] [Sheet resistance value] The sheet resistance of the thick film resistor was measured by the four-terminal method using a multimeter (KEITHLEY, Model 2001).

[0067] [Current noise] The current noise was measured by applying 1 / 10 W using a noise meter (Model 315C, manufactured by Quan-Tech).

[0068] Table 2 shows the measurement results of the sheet resistance and current noise.

[0069] Example 2 A thick-film resistor was obtained and evaluated in the same manner as in Example 1, except that a thick-film resistor composition containing ruthenium dioxide, glass frit, and steatite in proportions of 17.2 mass%, 73.0 mass%, and 9.8 mass%, was used.

[0070] Example 3 A thick-film resistor was obtained and evaluated in the same manner as in Example 1, except that a thick-film resistor composition containing ruthenium dioxide, glass frit, and steatite in proportions of 17.4 mass%, 68.6 mass%, and 14.0 mass%, was used.

[0071] Comparative Example 1 A thick-film resistor was obtained and evaluated in the same manner as in Example 1, except that no steatite was added and a thick-film resistor composition containing ruthenium dioxide and glass frit in proportions of 15.0 mass % and 85.0 mass % was used.

[0072] Comparative Example 2 A thick-film resistor was obtained and evaluated in the same manner as in Example 1, except that no steatite was added and a thick-film resistor composition containing ruthenium dioxide and glass frit in proportions of 10.0 mass % and 90.0 mass % was used.

[0073] Comparative Example 3 A thick-film resistor was obtained and evaluated in the same manner as in Example 1, except that no steatite was added and a thick-film resistor composition containing ruthenium dioxide and glass frit in proportions of 7.5% by mass and 92.5% by mass was used.

[0074] Comparative Example 4 A thick-film resistor was obtained and evaluated in the same manner as in Example 1, except that a thick-film resistor composition containing ruthenium dioxide, glass frit, and steatite in proportions of 17.5 mass%, 80.0 mass%, and 2.5 mass%, was used.

[0075] Comparative Example 5 A thick-film resistor was obtained and evaluated in the same manner as in Example 1, except that a thick-film resistor composition containing ruthenium dioxide, glass frit, and steatite in proportions of 17.5 mass%, 65.0 mass%, and 17.5 mass%, was used.

[0076] [Table 1]

[0077] [Table 2]

[0078] [Consideration] From the electrical characteristics of the thick-film resistors produced in the examples and comparative examples of the present invention, it can be seen that the thick-film resistors using steatite as an additive (Examples 1 to 3) have sufficiently small current noise according to the desired sheet resistance value and are superior as thick-film resistors, compared with thick-film resistors not containing an additive (Comparative Examples 1 to 3) and thick-film resistors in which the amount of steatite added is outside the range of the present invention (Comparative Examples 4 and 5).

Claims

1. A conductive powder and a glass frit are included, the conductive powder is made of ruthenium dioxide and / or alkaline earth metal ruthenate, and the content of the conductive powder is 5% by mass or more and 17.5% by mass or less; The glass frit is substantially free of lead and is made of alkaline earth zinc aluminoborosilicate glass (SiO ２ -B ２ O ３ -RO-ZnO-Al ２ O ３ : R is at least one selected from Ca, Sr, and Ba), borosilicate glass (SiO ２ -B ２ O ３ ), aluminoborosilicate glass (SiO ２ -B ２ O ３ -Al ２ O ３ ), or alkaline earth borosilicate glass (SiO ２ -B ２ O ３ -RO: R is at least one selected from Ca, Sr, and Ba), and the content of the glass frit is 70 mass% or more and 92 mass% or less, and Characterized in that 3.0% by mass or more and 15.0% by mass or less of steatite is added. A composition for thick film resistors.

2. 2. The composition for a thick film resistor according to claim 1, wherein the amount of the steatite added is from 5.0% by mass to 14.0% by mass, and the content of the glass frit is from 70% by mass to 90% by mass.

3. A paste for a thick film resistor, comprising a composition for a thick film resistor and an organic vehicle, the composition for a thick film resistor being the composition for a thick film resistor according to claim 1 or 2.

4. 4. The paste for a thick film resistor according to claim 3, wherein the content of the organic vehicle is 30% by mass or more and 50% by mass or less based on the mass of the paste for a thick film resistor.

5. It is made of a sintered body containing a conductive component, a glass component, and steatite, the conductive component is made of ruthenium dioxide and / or alkaline earth metal ruthenate, and the content of the conductive component is 5% by mass or more and 17.5% by mass or less; The glass component is substantially free of lead and is an alkaline earth zinc aluminoborosilicate glass (SiO ２ -B ２ O ３ -RO-ZnO-Al ２ O ３ : R is at least one selected from Ca, Sr, and Ba), borosilicate glass (SiO ２ -B ２ O ３ ), aluminoborosilicate glass (SiO ２ -B ２ O ３ -Al ２ O ３ ), or alkaline earth borosilicate glass (SiO ２ -B ２ O ３ -RO: R is at least one selected from Ca, Sr, and Ba), and the content of the glass component is 70 mass% or more and 92 mass% or less, and The conductive component, the glass component, and the steatite are contained in an amount of 3.0 mass% or more and 15.0 mass% or less. A thick film resistor that is substantially free of lead.

6. 6. The thick film resistor according to claim 5, wherein the amount of steatite added is 5.0% by mass or more and 14.0% by mass or less, and the content of the glass component is 70% by mass or more and 90% by mass or less.

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