Thick film resistive paste, thick film resistor and electronic component

Abstract

Disclosed is a thick film resistor paste which, while using a lead borosilicate glass as an insulating material, has no appearance crack abnormality and has sufficient surge resistance, a thick film resistor body using the thick film resistor paste, and an electronic component provided with the thick film resistor body. The thick film resistor paste contains a ruthenium oxide-containing glass powder and an organic vehicle. The ruthenium oxide-containing glass powder contains 10 mass% or more and 60 mass% or less of ruthenium oxide. In the glass composition, 60 mass% or less of silicon oxide, 30 mass% or more and 90 mass% or less of lead oxide, and 5 mass% or more and 50 mass% or less of boron oxide are contained with respect to 100 mass% of the glass components. The total content of the silicon oxide, the lead oxide, and the boron oxide is 50 mass% or more with respect to 100 mass% of the glass components.

Description

Technical Field

[0001] This invention relates to thick film resistor paste, and more specifically, to thick film resistor paste containing ruthenium oxide glass powder, which is particularly capable of forming a thick film resistor with a crack-free appearance and excellent surge resistance, thick film resistor using the thick film resistor paste, and electronic components having the thick film resistor. Background Technology

[0002] Thick-film resistor paste typically consists of conductive powder, glass powder, and an organic vehicle that forms the paste suitable for printing. This thick-film resistor paste is printed in any pattern, and the glass is sintered at a high temperature, typically 800–1000°C. This allows it to be used, for example, as a thick-film resistor in electronic components such as thick-film chip resistors. Since the resistance value can be gradually changed by adjusting the mixing ratio with the glass powder, ruthenium oxide powder and lead ruthenate powder are widely used as conductive powders.

[0003] For example, Patent Document 1 describes a technique for obtaining a resistive paste by adding a carrier using ethyl cellulose as a binder and toluene and ethanol as solvents to a mixture of mullite as inorganic particles, lead borosilicate glass as glass particles, and ruthenium dioxide as conductive particles, and then using the resistive paste to form a thick film resistor.

[0004] Furthermore, Patent Document 2 describes a technique for adding a resistive paste to a mixture of zircon as inorganic particles, lead borosilicate glass as glass particles, and ruthenium oxide as conductive particles, using ethyl cellulose as a binder and terpineol and butyl carbitol acetate as solvents, and a thick film resistor formed using the resistive paste.

[0005] In recent years, with the miniaturization of electronic components such as thick-film chip resistors, there is a demand for improved electrical performance of thick-film resistors, especially those with crack-free appearance and excellent surge resistance. When a momentary high voltage (surge voltage) is applied to a thick-film resistor, it typically exhibits a negative resistance change, but the smaller this change, the better. This negative resistance change is attributed to the heat generated during voltage application. In existing thick-film resistor pastes, glass powders bond together during sintering, but the softening of the glass powder is limited to the surface layer. Therefore, a dielectric layer corresponding to the glass particle size exists in the thick-film resistor after sintering the thick-film resistor paste. Conductive powder is distributed around this dielectric layer, giving the thick-film resistor conductivity. In the case of forming low-resistance resistors, ruthenium oxide powder is suitable as the conductive powder; however, because ruthenium oxide lacks sinterability, it is prone to cracking, especially in low-resistance resistors containing a large amount of ruthenium oxide.

[0006] Patent document 3 describes a technique that further includes a polycarboxylic acid dispersant in a resistive paste comprising carbon-based conductive powder, p-tert-butylphenol, and a substituted monophenolic resin obtained by condensation reaction with formaldehyde, thereby reducing cracking.

[0007] Existing technical documents

[0008] Patent documents

[0009] Patent Document 1: Japanese Patent Application Publication No. 4-320003

[0010] Patent Document 2: Japanese Patent Application Publication No. 6-163202

[0011] Patent Document 3: Japanese Patent No. 4706703 Summary of the Invention

[0012] The problem that the invention aims to solve

[0013] However, in recent years, the development of more miniaturized electronic components has led to the requirement for thick-film resistors that are less prone to cracking even when glass is used as the insulating material, in order to achieve higher heat resistance.

[0014] The purpose of this invention is to provide a thick-film resistor paste that, while using lead borosilicate glass as an insulating material, has no abnormal cracks in appearance and has sufficient surge resistance, a thick-film resistor body using the thick-film resistor paste, and an electronic component having the thick-film resistor body.

[0015] Methods for solving problems

[0016] Through various research results, the inventors discovered that when a thick-film resistor is formed by using a thick-film resistor paste containing ruthenium oxide glass powder of a specific composition, the incidence of cracks is reduced compared to the past, thus leading to and completing the present invention.

[0017] That is, the thick film resistive paste of the present invention is characterized by containing ruthenium oxide glass powder and an organic carrier, wherein the aforementioned ruthenium oxide glass powder contains 10% by mass and 60% by mass of ruthenium oxide, and the glass composition contains, relative to 100% by mass, 3% by mass and 60% by mass of silicon oxide, 30% by mass and 90% by mass of lead oxide, and 5% by mass and 50% by mass of boron oxide, and the total content of silicon oxide, lead oxide and boron oxide is 50% by mass and above relative to 100% by mass of the glass composition.

[0018] Furthermore, in the thick film resistive paste of the present invention, the average particle size of the aforementioned ruthenium oxide-containing glass powder is preferably 5 μm or less.

[0019] Furthermore, the thick film resistor of the present invention is characterized in that it is formed from a sintered body of any of the thick film resistor pastes of the present invention described above.

[0020] Furthermore, the electronic component of the present invention is characterized by having the thick film resistor described above.

[0021] Invention Effects

[0022] According to the present invention, a thick-film resistor paste that reduces the incidence of cracks on the surface of the resistor compared to the past and has sufficient surge resistance can be provided, a thick-film resistor using the thick-film resistor paste, and an electronic component having the thick-film resistor. Attached Figure Description

[0023] [ Figure 1 [Image 1] is a metallographic microscope image of the resistive surface of Example 1.

[0024] [ Figure 2 [Image 1] is a metallographic microscope image of the resistive surface of Comparative Example 1. Detailed Implementation

[0025] The embodiments of the present invention will be described below, but the present invention is not limited to the embodiments described below. Various modifications and substitutions can be added to the embodiments described below within the scope of the present invention.

[0026] The thick-film resistive paste of this embodiment contains ruthenium oxide glass powder and an organic carrier. The components are described in detail below.

[0027] (Conductive material)

[0028] The conductive material in the thick-film resistive paste of the present invention is ruthenium oxide. Conventional thick-film resistive pastes contain conductive materials and glass separately in powder form. However, in the thick-film resistive paste of the present invention, ruthenium oxide powder is not used alone as a conductive material. Instead, a structure containing ruthenium oxide-containing glass powder is formed. This ruthenium oxide-containing glass powder is obtained by using the ruthenium oxide powder as a conductive material as part of the raw material to produce ruthenium oxide-containing glass, and then pulverizing this ruthenium oxide-containing glass.

[0029] There is no particular limitation on the particle size of ruthenium oxide used in forming ruthenium oxide-containing glass powder, but a particle size of 5 μm is preferred. 2 Particle sizes with a specific surface area of ​​≥ 5 m² / g are preferred. 2 When the particle size of ruthenium oxide is too large, the uniformity of the conductive area in the thick film resistor will be reduced, and the surge resistance performance may be worse.

[0030] (Glass composition)

[0031] The ruthenium oxide-containing glass in the thick-film resistive paste of the present invention uses a glass composition containing silicon oxide (SiO2), lead oxide (PbO), and boron oxide (B2O3). In addition, it may also contain magnesium oxide (MgO), calcium oxide (CaO), barium oxide (BaO), strontium oxide (SrO), cadmium oxide (CdO), tin oxide (SnO), zinc oxide (ZnO), bismuth oxide (Bi2O3), etc. Furthermore, it may also contain aluminum oxide (Al2O3).

[0032] (Silicon oxide: SiO2)

[0033] SiO2 is a component constituting the framework of the glass composition of the present invention, and its proportion is 3% by mass or more and 60% by mass or less relative to 100% by mass of the glass composition contained in the ruthenium oxide glass. If it is greater than 60% by mass, the softening point of the resulting glass will become too high. Furthermore, if it is less than 3% by mass, a chemically stable glass cannot be obtained.

[0034] (Lead oxide: PbO)

[0035] PbO has the effect of lowering the softening point and promoting wetting with ruthenium oxide, thus improving dispersibility. Its proportion should be 30% to 90% by mass relative to 100% by mass of the glass composition in ruthenium oxide glass. If it is less than 30% by mass, the softening point of the resulting glass will become too high. Furthermore, if it is greater than 90% by mass, it is difficult to obtain a chemically stable glass state.

[0036] (Boron oxide: B2O3)

[0037] Both B2O3 and SiO2 are components that form the framework of the glass composition of this invention, and have the effect of lowering the softening point of the formed glass. The amount of B2O3 is 5% to 50% by mass relative to 100% by mass of the glass composition in the ruthenium oxide glass. If it is less than 5% by mass, the toughness of the formed glass decreases, making it prone to cracking, and the laser trimming properties deteriorate. Furthermore, if it is greater than 50% by mass, the glass composition is prone to phase separation, and the water resistance also decreases.

[0038] (Total content of essential glass components)

[0039] The total content of SiO2, PbO, and B2O3 in 100% by mass of the glass composition in the ruthenium oxide glass is 50% by mass or more. If it is less than 50% by mass, it is difficult to form a stable glass, and it is difficult to meet the surge resistance performance of the thick film resistor in this invention.

[0040] (Other glass components)

[0041] In addition to the essential glass components mentioned above, to enhance various properties without degrading the properties of ruthenium oxide glass, oxides may be further included as glass components. Specifically, Al₂O₃, MgO, CaO, BaO, SrO, CdO, SnO, ZnO, Bi₂O₃, etc., may be included. The amount of these glass components is 20% by mass or less relative to 100% of the total glass components in the ruthenium oxide glass.

[0042] (Ruthenium oxide glass)

[0043] In the ruthenium oxide-containing glass used in the thick-film resistive paste of the present invention, the ratio of ruthenium oxide, as a conductive material, to the glass composition is such that, relative to 100% by mass of the ruthenium oxide-containing glass composition, the ruthenium oxide content is set to 10% by mass or more and 60% by mass or less, and the glass composition is set to 40% by mass or more and 90% by mass or less. If the ruthenium oxide content is less than 10% by mass, the resistivity of the manufactured ruthenium oxide-containing glass powder becomes too high, exhibiting almost no conductivity. Furthermore, if it is more than 60% by mass, the glass composition cannot completely cover the ruthenium oxide powder, and the ruthenium oxide-containing glass becomes brittle. By adjusting the ratio of ruthenium oxide to the glass composition, the resistance value of the thick-film resistor can be adjusted to be close to the target resistance value.

[0044] Ruthenium oxide glass is pulverized to an average particle size of less than 5 μm. If the average particle size is greater than 5 μm, the uniformity of the thick-film resistor decreases, its surge resistance deteriorates, and cracks may form on the surface of the thick-film resistor, making it undesirable. Ball mills, planetary mills, and bead mills can be used as pulverizing methods.

[0045] It should be noted that in this invention, the average particle size refers to the median particle size, which is the value measured by ultrasonically dispersing the powder to be tested in a sodium hexametaphosphate aqueous solution (2 g / L) using a particle size analyzer (HPA9320-100X, manufactured by Micro TrackBell) with pure water solvent.

[0046] (Other additives)

[0047] In the thick-film resistive paste of the present invention, for the purpose of adjusting and improving the resistivity, TCR, and other properties of the thick-film resistive body, borosilicate glass without conductive materials and commonly used additives may be further included. Furthermore, to improve dispersibility, a dispersant may be included as an additive. Examples of main additives include niobium oxide (Nb₂O₅), tantalum oxide (Ta₂O₅), titanium oxide (TiO₂), copper oxide (CuO), manganese oxide (MnO₂), zirconium oxide (ZrO₂), and aluminum oxide (Al₂O₃). The content of the additives can be adjusted according to the target improved properties, and is preferably 10% by mass or less out of 100% by mass of the total inorganic matter.

[0048] (Organic carrier)

[0049] The organic carrier used in the thick-film resistive paste of the present invention is not particularly limited, and can be a substance commonly used in resistive pastes, which is made by dissolving resins such as ethyl cellulose and rosin in solvents such as terpineol. The amount of organic carrier can be adjusted appropriately according to the printing method, etc., and is usually 20% to 50% by mass relative to 100% of the total amount of resistive paste.

[0050] (Manufacturing method of thick film resistor paste)

[0051] There are no particular limitations on the method of manufacturing thick film resistive paste by mixing ruthenium oxide glass and organic carrier, and adding lead borosilicate glass powder and additives as needed. Common three-roll mills, bead mills, etc. can be used.

[0052] (Manufacturing method of thick film resistors)

[0053] The obtained thick film resistor paste is printed on a ceramic substrate, and after the organic solvent is removed by drying, a thick film resistor can be obtained by firing at a temperature of, for example, 800°C to 900°C.

[0054] Example

[0055] The present invention will be further described below with reference to detailed embodiments, but the present invention is not limited to these embodiments.

[0056] (Evaluation of a 100Ω resistivity element in Example 1)

[0057] Ruthenium oxide glass is produced by mixing and melting glass materials at a ratio of 60% by mass and ruthenium oxide at 40% by mass, followed by cooling. The composition of the resulting conductive glass is as follows (relative to 100% by mass): SiO2 33% by mass, PbO 48% by mass, Al2O3 5% by mass, B2O3 7% by mass, ZnO 2% by mass, and CaO 5% by mass.

[0058] The obtained ruthenium oxide-containing glass was pulverized using a ball mill to an average particle size of approximately 1 μm. A thick-film resistor composition comprising 55% by mass of ruthenium oxide-containing glass powder, 15% by mass of lead borosilicate glass, 1% by mass of Nb₂O₅ as an additive, and the remainder being an organic carrier, was prepared by mixing using a three-roll mill to disperse the various inorganic materials within the organic carrier, thus preparing the thick-film resistor paste of Example 1. It should be noted that the lead borosilicate glass powder used contained, relative to 100% by mass of glass composition, 33% by mass of SiO₂, 48% by mass of PbO, 5% by mass of Al₂O₃, 7% by mass of B₂O₃, 2% by mass of ZnO, and 5% by mass of CaO. The organic carrier was a substance obtained by dissolving 20 parts by mass of ethyl cellulose in 100 parts by mass of terpineol. The composition of the thick-film resistor paste of Example 1 and the composition of the ruthenium oxide-containing glass used in the manufacture of the thick-film resistor paste are shown in Table 1.

[0059] <Evaluation Experiment>

[0060] (Preparation of evaluation samples)

[0061] Between five pairs of electrodes spaced 1.0 mm apart and pre-printed on an alumina substrate, the prepared thick-film resistive paste was printed to a width of 1.0 mm and dried in a belt furnace at a peak temperature of 150°C for 5 minutes. Afterward, it was fired in a belt furnace at a peak temperature of 850°C for 9 minutes. Five samples with the same treatment were prepared on each alumina substrate, resulting in 25 thick-film resistors for evaluation sample 1.

[0062] In addition, except for printing a width of 0.3 mm between electrodes spaced at 0.3 mm intervals, thick film resistors (5 pieces) for evaluation sample 2 were prepared by fabricating one sheet per alumina substrate using the same method as evaluation sample 1.

[0063] (Film thickness measurement)

[0064] For film thickness, a stylus-type surface roughness meter was used to select any one of the evaluation samples 1, with the alumina substrate as the unit, and the film thickness of 5 thick film resistors was measured respectively. The average value of the 5 samples was taken as the actual measured film thickness.

[0065] (Converting area resistivity)

[0066] The resistance values ​​at 25°C of 5 evaluation samples (25 samples in total) formed on 5 alumina substrates were measured using a circuit calibrator (2001 MULTIMETER, manufactured by Keithley Corporation), and the average value was taken as the actual measured resistance value. The equivalent area resistivity value for a film thickness of 7 μm was calculated using the following formula (1). The calculated equivalent area resistivity values ​​are shown in Table 3.

[0067] Converted area resistivity (Ω) = Actual measured resistance (Ω) × (Actual measured film thickness (μm) / 7 (μm)) ... (1)

[0068] (Temperature coefficient of resistance: TCR)

[0069] For evaluation sample 1, which was formed on an alumina substrate, the resistance values ​​of five thick-film resistors were measured after being held in a constant temperature bath at -55°C, 25°C, and 125°C for 30 minutes. The measured resistance values ​​were taken as R0. -55 R 25 R 125 The low-temperature TCR was calculated using formula (2), and the high-temperature TCR was calculated using formula (3). The average values ​​of the low-temperature TCR and high-temperature TCR of the five samples are shown in Table 3.

[0070] Low-temperature TCR (ppm / ℃) = [(R -55 -R 25 ) / R 25 ] / (-80)×10 6 …(2)

[0071] High-temperature TCR (ppm / ℃) = [(R 125 -R 25 ) / R 25 ] / (100)×10 6 …(3)

[0072] (Evaluation of surge resistance performance: rate of change of resistance value)

[0073] For the thick-film resistor of evaluation sample 2, an electrostatic discharge test was conducted using a semiconductor electrostatic discharge tester (ESS-6008, manufactured by Noise Research Institute) with a voltage applied under the conditions of a 200pF capacitance and 0Ω internal resistance. A 4kV voltage was applied to the thick-film resistor of evaluation sample 2 five times at 1-second intervals. The resistance value Rs before voltage application and the resistance value Re after voltage application were measured, and the rate of change of resistance value was calculated using the following formula (4). The average value of the calculated resistance change rates of the five samples is shown in Table 3.

[0074] Resistance change rate (%) = (Re - Rs) / Rs × 100…(4)

[0075] (Observation of the surface of a thick-film resistor)

[0076] The surface of the thick-film resistor in sample 1 was observed and evaluated using a metallographic microscope. The appearance level of localized micro-voids due to sintering was rated as "0", while the appearance level of crack-like defects due to the connection of multiple voids was rated as "×". The evaluation results are shown in Table 3, and the metallographic microscope images of the observed surface are as follows: Figure 1 As shown.

[0077] (Examples 2-12)

[0078] Ruthenium oxide glass was produced by mixing and melting glass materials and ruthenium oxide in the proportions shown in Table 1, followed by cooling. The contents of SiO2, PbO, Al2O3, B2O3, ZnO, and CaO relative to 100% by mass of the glass composition in the produced conductive glasses are shown in Table 1.

[0079] The obtained ruthenium oxide-containing glasses were pulverized using a ball mill to achieve average particle sizes as shown in Table 1. Thick-film resistor compositions containing ruthenium oxide-containing glass powder, lead borosilicate glass, additives, and an organic carrier in the proportions shown in Table 1 were mixed using a three-roll mill to disperse the various inorganic materials within the organic carrier, thus preparing the thick-film resistor pastes of Examples 2-12. The lead borosilicate glass powder and organic carrier had the same composition as those used in Example 1.

[0080] Furthermore, thick-film resistivity samples for evaluation were prepared using the same method as in Example 1, and the same evaluation was performed as in Example 1. The evaluation results are shown in Table 3.

[0081] (Comparative Example 1)

[0082] Instead of using ruthenium oxide-containing glass, a thick-film resistive paste was prepared by separately adding a conductive material and glass in powder form using a conventional manufacturing method. However, when ruthenium oxide powder and glass powder are added separately instead of ruthenium oxide-containing glass powder obtained by pulverizing ruthenium oxide-containing glass, differences in electrical resistance characteristics (TCR) and other properties occur if the resistivity is adjusted to suit the thick-film resistive paste. Therefore, in Comparative Example 1 prepared using a conventional manufacturing method, lead ruthenate was added as a conductive material in addition to ruthenium oxide to adjust the TCR and other properties, and the amounts of each additive were adjusted. That is, a thick-film resistor composition containing 17% by mass ruthenium oxide powder, 4% by mass lead ruthenate powder, 43% by mass glass powder, 1% by mass Mn2O3 and 1% by mass Nb2O5 as additives, with the remainder being an organic carrier, was prepared. The inorganic materials were dispersed in the organic carrier by mixing using a three-roll mill to produce the thick-film resistor paste of Comparative Example 1. The glass composition in the prepared thick-film resistor paste was as follows, relative to 100% by mass of glass: 33% by mass SiO2, 46% by mass PbO, 5% by mass Al2O3, 7% by mass B2O3, 3% by mass ZnO, and 6% by mass CaO. The organic carrier had the same composition as that used in Example 1. The composition of the thick-film resistor paste of Comparative Example 1 and the composition of the glass used in the manufacture of the thick-film resistor paste are shown in Table 2.

[0083] Furthermore, thick-film resistivity samples for evaluation were fabricated using the same method as in Example 1, and the same evaluation was performed as in Example 1. The evaluation results are shown in Table 3, and the metallographic micrographs observed on the surface are as follows: Figure 2 As shown.

[0084] (Comparative Examples 2-10)

[0085] Ruthenium oxide glass was produced by mixing and melting glass materials and ruthenium oxide in the proportions shown in Table 1, followed by cooling. The contents of SiO2, PbO, Al2O3, B2O3, ZnO, and CaO relative to 100% by mass of the glass composition in the produced conductive glasses are shown in Table 1.

[0086] The obtained ruthenium oxide-containing glasses were pulverized using a ball mill to achieve average particle sizes as shown in Table 1. Thick-film resistor compositions containing ruthenium oxide-containing glass powder, lead borosilicate glass, additives, and an organic carrier in the proportions shown in Table 1 were mixed using a three-roll mill to disperse the various inorganic materials within the organic carrier, thus preparing thick-film resistor pastes for Comparative Examples 2-10. The lead borosilicate glass powder and organic carrier had the same composition as those used in Example 1.

[0087] Furthermore, thick-film resistivity samples for evaluation were prepared using the same method as in Example 1, and the same evaluation was performed as in Example 1. The evaluation results are shown in Table 3.

[0088] [Table 1]

[0089]

[0090] * The contents of ruthenium oxide glass powder, organic carrier, lead borosilicate glass powder, niobium oxide, and manganese oxide are relative to 100 wt% of the thick film resistive paste composition.

[0091] *The ruthenium oxide content is the content relative to 100 wt% of the ruthenium oxide-containing glass composition.

[0092] *The content of silicon oxide, lead oxide, boron oxide, their combined content, aluminum oxide, zinc oxide, and calcium oxide are all relative to the glass composition per 100 wt%.

[0093] [Table 2]

[0094]

[0095] * The contents of ruthenium oxide powder, lead ruthenate powder, glass powder, organic carrier, niobium oxide, and manganese oxide are the contents relative to 100 wt% of the thick film resistive paste composition.

[0096] *The contents of silicon oxide, lead oxide, boron oxide, aluminum oxide, zinc oxide, and calcium oxide are relative to 100 wt% of the glass composition.

[0097] [Table 3]

[0098]

[0099] As shown in Table 3, it was confirmed that, compared with the thick film resistor of Comparative Example 1 formed by the existing thick film resistor paste made without using ruthenium oxide glass powder, the thick film resistors of Examples 1 to 12 formed by using the thick film resistor paste made with ruthenium oxide glass powder of the present invention showed that the crack generation on the surface of the thick film resistor was suppressed, the resistance value change rate before and after the electrostatic discharge test was small, and it had excellent surge resistance performance.

[0100] Furthermore, in the thick film resistive body of Comparative Example 2, which was formed by using a thick film resistive paste obtained by using a ruthenium oxide-containing glass with a ruthenium oxide content less than the required range of the present invention, it was confirmed that the resistance value of the conductive glass powder became too high, and it hardly showed any conductivity.

[0101] Furthermore, in the thick film resistor of Comparative Example 3, which was formed by using a thick film resistor paste obtained by using a ruthenium oxide-containing glass with a ruthenium oxide content exceeding the scope of the present invention, crack-like defects were confirmed to exist on the surface.

[0102] Furthermore, in the thick film resistors of Comparative Examples 4 to 10 formed by using thick film resistor pastes obtained by using glass components with contents of silicon oxide, lead oxide, or boron oxide, or the total content of these essential glass components exceeding the scope of the present invention, it was confirmed that compared with the thick film resistors of Examples 1 to 12, the rate of change of resistance value before and after the electrostatic discharge test was high and the surge resistance performance was poor.

[0103] The above test results confirm that the crack generation of the thick film resistor formed using the thick film resistor paste of the present invention is suppressed, and it has excellent surge resistance performance, making it suitable for use in electronic components that have been developing towards miniaturization in recent years.

Claims

1. A thick-film resistor paste, characterized in that, Contains ruthenium oxide glass powder and an organic carrier. The ruthenium oxide-containing glass powder contains more than 10% by mass and less than 60% by mass of ruthenium oxide. Furthermore, the glass composition contains, relative to 100% by mass, 33% to 60% by mass of silicon dioxide, 30% to 90% by mass of lead oxide, and 5% to 50% by mass of boron oxide. Furthermore, relative to 100% by mass of the glass composition, the combined content of silicon oxide, lead oxide, and boron oxide is 50% by mass or more.

2. The thick film resistive paste according to claim 1, characterized in that, The average particle size of the ruthenium oxide-containing glass powder is less than 5 μm.

3. A thick film resistor formed from a sintered body of the thick film resistor paste as described in claim 1 or 2.

4. An electronic component comprising the thick-film resistor as described in claim 3.

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