A resistor paste and its preparation method

Abstract

This application relates to the technical field of resistor pastes, and provides a resistor paste and a preparation method thereof, including: 70 - 112 parts of conductive phase material, 0.1 - 3 parts of temperature coefficient regulator, 0.1 - 2 parts of thermal expansion coefficient regulator, 0.1 - 5 parts of sintering activator, 2 - 5 parts of glass powder, and 14 - 41 parts of organic carrier. For the resistor paste provided in this application, the conductive phase material is the core component, which is used to form a continuous and dense conductive network; the temperature coefficient regulator controls the resistance temperature coefficient of the resistor paste, enabling the resistor paste to maintain a stable resistance value within a wider temperature range; the thermal expansion coefficient regulator reduces the thermal expansion coefficient of the resistor paste, making it compatible with the substrate and avoiding the cracking problem after sintering caused by an excessive thermal expansion coefficient; the sintering activator reduces the sintering temperature of the resistor paste, promotes the diffusion and rearrangement between particles, increases the sintering density, improves the bonding between the paste and the substrate, and enhances the stability and reliability of the resistor body.

Description

Technical Field

[0001] This application belongs to the technical field of resistor pastes, and particularly relates to a resistor paste and a preparation method thereof. Background Art

[0002] Chip resistors, as indispensable electronic components in modern electronic devices, undertake key functions such as voltage division, current limiting, and signal processing. With the rapid development of electronic technology, chip resistors are gradually developing towards high precision, miniaturization, and high reliability to meet the requirements of increasingly complex electronic systems. As one of the key materials for chip resistors, the performance of resistor pastes is directly related to the electrical properties, durability, and consistency of resistors, so it is particularly important.

[0003] Ruthenium-based resistor pastes play a crucial role in the manufacture of chip resistors due to their excellent electrical conductivity, outstanding chemical stability, and excellent high-temperature resistance. The core conductive component is ruthenium dioxide (RuO2). Although RuO2 has high-temperature stability as a conductive phase, since it is difficult to form a dense sintering network under low-temperature conditions, ruthenium-based resistor pastes require a relatively high sintering temperature to achieve tight bonding between particles. The high sintering temperature not only increases production costs but also may cause thermal damage to the substrate, thus limiting the wide application of ruthenium-based resistor pastes in some temperature-sensitive application scenarios. Moreover, there is often a problem of mismatch in the thermal expansion coefficients between existing ruthenium-based resistor pastes and substrates (such as Al2O3 substrates). During the sintering process, due to temperature changes, large thermal stresses will be generated between the paste and the substrate, resulting in microcracks after sintering. This will not only damage the electrical properties of the resistor but also affect its long-term stability.

[0004] Therefore, there is an urgent need to develop a resistor paste with a low sintering temperature, stable performance, and good compatibility with the substrate. Summary of the Invention

[0005] The purpose of this application is to provide a resistor paste and a preparation method thereof, aiming to solve the problems of high sintering temperature, unstable performance, and mismatch in thermal expansion coefficient between the existing ruthenium-based resistor pastes and the substrate.

[0006] To achieve the above application purpose, the technical solution adopted in this application is as follows:

[0007] In the first aspect, this application provides a resistor paste, which includes the following components in parts by weight: 70 - 112 parts of conductive phase material, 0.1 - 3 parts of temperature coefficient regulator, 0.1 - 2 parts of thermal expansion coefficient regulator, 0.1 - 5 parts of sintering activator, 2 - 5 parts of glass powder, and 14 - 41 parts of organic carrier.

[0008] Second aspect, the present application provides a method for preparing a resist paste, comprising the following steps:

[0009] Pre-mix the conductive phase material, the thermal expansion coefficient regulator and the sintering activator to obtain a mixed powder;

[0010] Add the temperature coefficient regulator to the organic carrier for mixing treatment to obtain a suspension;

[0011] Add the mixed powder and the glass powder to the suspension for dispersion treatment, then perform three-roll ball milling treatment, and filter to obtain the resist paste.

[0012] Compared with the prior art, the present application has the following beneficial effects:

[0013] For the resist paste provided in the first aspect of the present application, the conductive phase material, as the core component of the resist paste, is used to form a continuous and dense conductive network; the added temperature coefficient regulator can precisely control the resistance temperature coefficient of the resist paste, enabling the resist paste to maintain a stable resistance value within a wider temperature range, thereby improving the thermal stability and reliability of the resistor body made of the resist paste; the added thermal expansion coefficient regulator can reduce the thermal expansion coefficient of the resist paste, making it compatible with the substrate and avoiding the problem of cracking after sintering caused by too large a thermal expansion coefficient; the added sintering activator can reduce the sintering temperature of the resist paste and improve the sintering activity of the paste, thereby promoting the diffusion and rearrangement between particles, increasing the sintering density, improving the interfacial bonding between the resist paste and the substrate, and further reducing the interfacial defects and thermal stress caused by problems such as thermal expansion coefficient mismatch, and improving the stability and reliability of the resistor body. Therefore, under the synergistic effect of the temperature coefficient regulator, the thermal expansion coefficient regulator and the sintering activator in the resist paste of the present application, it is given a lower sintering temperature and excellent matrix compatibility, so that the performance of the sintered resistor body is stable.

[0014] For the method for preparing the resist paste provided in the second aspect of the present application, first pre-mix the ruthenium-containing mixture powder, the thermal expansion coefficient regulator and the sintering activator to make each component preliminarily mixed evenly to form a mixed powder, and add the temperature coefficient regulator to the organic carrier to form a suspension, and then add the mixed powder and the glass powder to the suspension for dispersion treatment, which can ensure that the powder is completely wetted and evenly dispersed, prevent agglomeration, and then after three-roll ball milling treatment and filtration, a resist paste with the target fineness can be obtained. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] To more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required in the embodiments or the description of the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0016] Figure 1 It is the SEM image of the resistor paste provided in Embodiment 1 of the present application. Detailed implementation manners

[0017] In order to make the technical problems to be solved, technical solutions and beneficial effects of the present application clearer, the following further details the present application in combination with embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0018] The first aspect of the embodiment of the present application provides a resistor paste, including the following components in parts by weight: 70 - 112 parts of conductive phase material, 0.1 - 3 parts of temperature coefficient regulator, 0.1 - 2 parts of coefficient of thermal expansion regulator, 0.1 - 5 parts of sintering activator, 2 - 5 parts of glass powder, and 14 - 41 parts of organic carrier.

[0019] For the resistor paste provided in the embodiment of the present application, the conductive phase material, as the core component of the resistor paste, is used to form a continuous and dense conductive network; the added temperature coefficient regulator can precisely control the temperature coefficient of resistance of the resistor paste, enabling the resistor paste to maintain a stable resistance value within a wider temperature range, thereby improving the thermal stability and reliability of the resistor body made of the resistor paste; the added coefficient of thermal expansion regulator can reduce the coefficient of thermal expansion of the resistor paste, making it compatible with the substrate and avoiding the problem of cracking after sintering caused by too large a coefficient of thermal expansion; the added sintering activator can reduce the sintering temperature of the resistor paste and improve the sintering activity of the paste, thereby promoting the diffusion and rearrangement between particles, increasing the sintering density, improving the interfacial bonding between the resistor paste and the substrate, and further reducing the interfacial defects and thermal stress caused by problems such as mismatch of the coefficient of thermal expansion, and improving the stability and reliability of the resistor body. Therefore, under the synergistic effect of the temperature coefficient regulator, coefficient of thermal expansion regulator and sintering activator in the resistor paste of the present application, it is given a lower sintering temperature and excellent matrix compatibility, so that the performance of the sintered resistor body is stable.

[0020] In an embodiment, the temperature coefficient regulator includes a positive temperature coefficient regulator and a negative temperature coefficient regulator with a mass ratio of (1 to 9)∶(1 to 9). By adding the positive temperature coefficient regulator and the negative temperature coefficient regulator and controlling the ratio between them, the resistance temperature coefficient of the resistance paste is reduced and stabilized within the range of ±50 ppm / °C, so that the fabricated resistor can maintain a stable resistance value within a wide temperature range and has excellent thermal stability and reliability.

[0021] In an embodiment, the positive temperature coefficient regulator includes LaMnO3, MoO3, and ZrO2; further, the mass ratio of LaMnO3, MoO3, and ZrO2 is (1 to 10)∶(20 to 50)∶(1 to 10). By synthesizing a composite oxide with a specific perovskite structure from LaMnO3, MoO3, and ZrO2, the linear regulation ability of the resistance temperature coefficient can be optimized and the long-term stability of the resistor can be improved.

[0022] In a specific embodiment, the positive temperature coefficient regulator further includes ethylene glycol, N-vinylpyrrolidone, and diethylene glycol butyl ether acetate, and the mass ratio of LaMnO3, MoO3, ZrO2, ethylene glycol, N-vinylpyrrolidone, and diethylene glycol butyl ether acetate is (1 to 10)∶(20 to 50)∶(1 to 10)∶(1 to 10)∶(1 to 10)∶(10 to 30).

[0023] In an embodiment, the negative temperature coefficient regulator includes NiMn2O4, SnO2, and Fe2O3; further, the mass ratio of NiMn2O4, SnO2, and Fe2O3 is (10 to 20)∶(1 to 10)∶(20 to 50). By synthesizing a composite oxide with a specific spinel structure from NiMn2O4, SnO2, and Fe2O3, the linear regulation ability of the resistance temperature coefficient can be optimized and the long-term stability of the resistor can be improved.

[0024] In a specific embodiment, the negative temperature coefficient regulator further includes ethylene glycol, N-vinylpyrrolidone, and diethylene glycol butyl ether acetate, and the mass ratio of NiMn2O4, SnO2, Fe2O3, ethylene glycol, N-vinylpyrrolidone, and diethylene glycol butyl ether acetate is (10 to 20)∶(1 to 10)∶(20 to 50)∶(1 to 10)∶(1 to 10)∶(10 to 30).

[0025] By forming a single composite perovskite or composite spinel phase, the above positive temperature coefficient regulator and negative temperature coefficient regulator can avoid the temperature drift problem caused by separately adding MnO2, Co2O3, and CuO.

[0026] In an embodiment, the thermal expansion coefficient regulator includes Al2O3, Si3N4, and B2O3 with a mass ratio of (75~95)∶(5~10)∶(0.1~5); Al2O3 and Si3N4 have extremely low thermal expansion coefficients. Adding them to the resistor paste can significantly reduce the thermal expansion coefficient of the resistor body, improve compatibility with the substrate, and avoid cracking problems after sintering caused by excessive thermal expansion coefficient. Adding B2O3 can reduce the carbon residue after resin sintering, thereby further reducing the thermal expansion coefficient. Therefore, under the synergistic effect of the ceramic oxides Al2O3, Si3N4, and B2O3 with ultra-low thermal expansion coefficients, the resistor paste is given a very small thermal expansion coefficient and has good compatibility with the substrate.

[0027] In an embodiment, the sintering activator is selected from at least one of nano-sized RuO2 powder, nano-sized ZrO2 powder, and nano-sized CuO powder. These sintering activators can significantly reduce the sintering temperature of the resistor paste, lower the sintering temperature from 850 °C to below 750 °C, improve the sintering density and interface bonding, and enhance the stability and reliability of the resistor body.

[0028] In an embodiment, the particle sizes of the nano-sized RuO2 powder, nano-sized ZrO2 powder, and nano-sized CuO powder are 10~300 nm.

[0029] In an embodiment, the conductive phase material includes ruthenium-containing mixture powder; specifically, the ruthenium-containing mixture powder includes 45~68 parts of ruthenium dioxide powder, 15~24 parts of bismuth ruthenate powder, and 10~20 parts of lead ruthenate powder.

[0030] In an embodiment, the particle sizes of the ruthenium dioxide powder, bismuth ruthenate powder, and lead ruthenate powder are 0.1~5 μm.

[0031] In an embodiment, the organic carrier includes 5~10 parts of ethyl cellulose, 2~8 parts of terpineol, 2~8 parts of ethylene glycol monobutyl ether, and 5~15 parts of ethylene glycol monobutyl ether acetate.

[0032] In an embodiment, the fineness of the resistor paste is ≤10 μm, the viscosity is 50~300 Pa·s, and the temperature coefficient is in the range of ±50 ppm / °C.

[0033] In an embodiment, the particle size of the glass powder is 0.5~3 μm.

[0034] In an embodiment, the glass powder includes Bi2O3, SiO2, B2O3, ZnO, Al2O3, and ZrO2 with a mass ratio of (40~60)∶(15~25 )∶(5~15)∶(5~10)∶(2~5)∶(1~5).

[0035] The second aspect of the embodiment of the present application provides a preparation method for the above resistor paste. The preparation method of the resistor paste of the present application includes the following steps:

[0036] S01: Premix the conductive phase material, thermal expansion coefficient regulator, and sintering activator to obtain a mixed powder.

[0037] S02: Add the temperature coefficient regulator to the organic carrier for mixing treatment to obtain a suspension.

[0038] S03: Add the mixed powder and glass powder to the suspension for dispersion treatment, then perform three-roll ball milling treatment, and filter to obtain the resistor paste.

[0039] For the method for preparing the resistor paste provided by the embodiment of the present application, first premix the conductive phase material, thermal expansion coefficient regulator, and sintering activator to make the components preliminarily mixed evenly to form a mixed powder, and add the temperature coefficient regulator to the organic carrier to form a suspension. Then add the mixed powder and glass powder to the suspension for dispersion treatment, which can ensure that the powder is completely wetted and evenly dispersed, prevent agglomeration, and then obtain the resistor paste with the target fineness after three-roll ball milling treatment and filtration.

[0040] The specific components and contents of the conductive phase material, thermal expansion coefficient regulator, sintering activator, temperature coefficient regulator, organic carrier, and glass powder in the above steps S01 to S03 are the same as those of the conductive phase material, thermal expansion coefficient regulator, sintering activator, temperature coefficient regulator, organic carrier, and glass powder included in the resistor paste of the embodiment of the present application in the foregoing text, and will not be elaborated here.

[0041] In the above step S01, in the embodiment, the step of premixing the conductive phase material, thermal expansion coefficient regulator, and sintering activator includes: Weigh appropriate amounts of the conductive phase material, thermal expansion coefficient regulator, and sintering activator according to the above component ratios and add them to a high-speed mixer for stirring evenly to obtain a mixed powder.

[0042] In the above step S02, in the embodiment, the step of preparing the positive temperature coefficient regulator includes: Weigh appropriate amounts of LaMnO3 powder, MoO3 powder, ZrO2 powder, ethylene glycol, N-vinylpyrrolidone, and diethylene glycol butyl ether acetate according to the mass ratio of LaMnO3, MoO3, ZrO2, ethylene glycol, N-vinylpyrrolidone, and diethylene glycol butyl ether acetate of (1 to 10):(20 to 50):(1 to 10):(1 to 10):(1 to 10):(10 to 30); Calcinate the LaMnO3 powder, MoO3 powder, and ZrO2 powder at 400 to 600 °C for 2 to 6 h to form a first composite oxide; Mix and process the first composite oxide, ethylene glycol, N-vinylpyrrolidone, and diethylene glycol butyl ether acetate to obtain the positive temperature coefficient regulator.

[0043] In an embodiment, the steps of preparing the negative temperature coefficient regulator include: weighing appropriate amounts of NiMn2O4 powder, SnO2 powder, Fe2O3 powder, ethylene glycol, N-vinylpyrrolidone, and diethylene glycol monobutyl ether acetate according to a mass ratio of NiMn2O4, SnO2, Fe2O3, ethylene glycol, N-vinylpyrrolidone, and diethylene glycol monobutyl ether acetate of (10-20):(1-10):(20-50):(1-10):(1-10):(10-30); calcining the NiMn2O4 powder, SnO2 powder, and Fe2O3 powder at 400-600 °C for 2-6 h to form a second composite oxide; and mixing and processing the second composite oxide, ethylene glycol, N-vinylpyrrolidone, and diethylene glycol monobutyl ether acetate to obtain the negative temperature coefficient regulator.

[0044] In an embodiment, the steps of adding the temperature coefficient regulator to the organic carrier for mixing and processing include: adding the positive temperature coefficient regulator and the negative temperature coefficient regulator to the organic carrier and stirring evenly to obtain a suspension.

[0045] In step S03 above, in an embodiment, the steps of adding the mixed powder and the glass powder to the suspension for dispersion processing include: adding the mixed powder to the suspension, using an ultrasonic-assisted ball milling device to fully disperse the mixture, and then adding the glass for full dispersion.

[0046] The following is illustrated with specific embodiments.

[0047] Embodiment 1

[0048] This embodiment provides a resistance paste and a preparation method thereof.

[0049] The resistance paste includes the following components in parts by weight: 57 parts of ruthenium dioxide powder, 20 parts of bismuth ruthenate powder, 15 parts of lead ruthenate powder, 0.8 part of positive temperature coefficient regulator, 0.7 part of negative temperature coefficient regulator, 1 part of thermal expansion coefficient regulator, 2.5 parts of nano-scale RuO2 powder, 3.5 parts of glass powder, 7.5 parts of ethyl cellulose, 5 parts of terpineol, 5 parts of ethylene glycol monobutyl ether, and 10 parts of ethylene glycol monobutyl ether acetate;

[0050] Among them, the positive temperature coefficient regulator is composed of LaMnO3, MoO3, ZrO2, ethylene glycol, N-vinylpyrrolidone, and diethylene glycol monobutyl ether acetate with a mass ratio of 6:35:6:5:6:20;

[0051] The negative temperature coefficient regulator is composed of NiMn2O4, SnO2, Fe2O3, ethylene glycol, N-vinylpyrrolidone, and diethylene glycol monobutyl ether acetate with a mass ratio of 15:6:35:5:6:20;

[0052] The thermal expansion coefficient regulator is composed of Al2O3 powder, Si3N4 powder and B2O3 powder with a mass ratio of 85∶7.5∶2.5;

[0053] The glass powder is composed of Bi2O3, SiO2, B2O3, ZnO, Al2O3 and ZrO2 with a mass ratio of 50∶20∶10∶7.5∶3.5∶3;

[0054] The D50 particle size of the glass powder is 2μm;

[0055] The D50 particle sizes of ruthenium dioxide powder, bismuth ruthenate powder and lead ruthenate powder are 2.5μm;

[0056] The D50 particle size of the nano-scale RuO2 powder is 150nm.

[0057] A method for preparing a resistor paste, comprising the following steps:

[0058] S11: Weigh appropriate amounts of the raw materials of each component according to the component ratios of the resistor paste in this embodiment;

[0059] S12: Add ruthenium dioxide powder, bismuth ruthenate powder, lead ruthenate powder, Al2O3 powder, Si3N4 powder, B2O3 powder and nano-scale RuO2 powder to a high-speed mixer and stir evenly to obtain a mixed powder;

[0060] S13: Calcinate LaMnO3 powder, MoO3 powder and ZrO2 powder at 500°C for 4h to form a first composite oxide; Mix the first composite oxide, ethylene glycol, N-vinylpyrrolidone and diethylene glycol butyl ether acetate evenly to obtain a positive temperature coefficient regulator;

[0061] Calcinate NiMn2O4 powder, SnO2 powder and Fe2O3 powder at 500°C for 4h to form a second composite oxide; Mix and process the second composite oxide, ethylene glycol, N-vinylpyrrolidone and diethylene glycol butyl ether acetate to obtain a negative temperature coefficient regulator;

[0062] Add the positive temperature coefficient regulator and the negative temperature coefficient regulator to an organic carrier of ethyl cellulose, terpineol, ethylene glycol monobutyl ether and diethylene glycol butyl ether acetate and stir evenly to obtain a suspension;

[0063] S14: Add the mixed powder to the suspension, use an ultrasonic-assisted ball milling device to fully disperse the mixed powder, then add the glass powder and continue ball milling to fully disperse, and then go through a three-roll ball milling process, grind 12 times, and filter to obtain the resistor paste.

[0064] Example 2

[0065] This example provides a resistor paste and a preparation method thereof. The difference from Example 1 is:

[0066] The resistive paste does not contain a positive temperature coefficient regulator.

[0067] Example 3

[0068] This example provides a resistive paste and a preparation method thereof. The difference from Example 1 is:

[0069] The resistive paste does not contain a negative temperature coefficient regulator.

[0070] Example 4

[0071] This example provides a resistive paste and a preparation method thereof. The difference from Example 1 is:

[0072] For the resistive paste, the thermal expansion coefficient regulator is composed of Al2O3 powder and Si3N4 powder with a mass ratio of 85:7.5.

[0073] Example 5

[0074] This example provides a resistive paste and a preparation method thereof. The difference from Example 1 is:

[0075] For the resistive paste, the thermal expansion coefficient regulator is B2O3 powder.

[0076] Example 6

[0077] This example provides a resistive paste and a preparation method thereof. The difference from Example 1 is:

[0078] For the resistive paste, 1 part of nano-sized ZrO2 powder and 0.5 part of nano-sized CuO powder are used to replace 2.5 parts of nano-sized RuO2 powder. The D50 particle size of the nano-sized ZrO2 powder and the nano-sized CuO powder is 150 nm.

[0079] Example 7

[0080] This example provides a resistive paste and a preparation method thereof. The difference from Example 1 is:

[0081] For the preparation method of the resistive paste, in step S13, LaMnO3 powder, MoO3 powder, ZrO2 powder, ethylene glycol, N-vinyl pyrrolidone and diethylene glycol butyl ether acetate are directly mixed evenly to obtain a positive temperature coefficient regulator; NiMn2O4 powder, SnO2 powder, Fe2O3 powder, ethylene glycol, N-vinyl pyrrolidone and diethylene glycol butyl ether acetate are directly mixed and processed to obtain a negative temperature coefficient regulator.

[0082] Comparative Example 1

[0083] This comparative example provides a resistive paste and a preparation method thereof.

[0084] A resistor paste, comprising the following components in parts by weight: 57 parts of ruthenium dioxide powder, 20 parts of bismuth ruthenate powder, 15 parts of lead ruthenate powder, 3.5 parts of glass powder, 7.5 parts of ethyl cellulose, 5 parts of terpineol, 5 parts of ethylene glycol monobutyl ether, and 10 parts of ethylene glycol monobutyl ether acetate;

[0085] Among them, the glass powder is composed of PbO, SiO2, B2O3, Al2O3, and ZnO with a mass ratio of 60∶15∶10∶3.5∶6; the D50 particle size of the glass powder is 2.0 μm;

[0086] The D50 particle size of the ruthenium dioxide powder, bismuth ruthenate powder, and lead ruthenate powder is 2.5 μm.

[0087] A method for preparing a resistor paste, comprising the following steps:

[0088] S11: Weigh appropriate amounts of each component raw material according to the component ratio of the resistor paste in this embodiment;

[0089] S12: Add the ruthenium dioxide powder, bismuth ruthenate powder, and lead ruthenate powder to a high-speed mixer and stir evenly to obtain a mixed powder;

[0090] S13: Mix the ethyl cellulose, terpineol, ethylene glycol monobutyl ether, and ethylene glycol monobutyl ether acetate evenly to obtain an organic carrier solution;

[0091] S14: Add the mixed powder to the organic carrier solution, use ultrasonic-assisted ball milling equipment to fully disperse the mixed powder, then add the glass powder and continue ball milling to fully disperse, and then go through a three-roll ball milling process, grind 12 times, and filter to obtain the resistor paste.

[0092] Comparative Example 2

[0093] This comparative example provides a resistor paste and a preparation method thereof, the difference from Example 1 is:

[0094] The resistor paste does not contain a positive temperature coefficient regulator and a negative temperature coefficient regulator.

[0095] For the preparation method of the resistor paste, in step S13, the ethyl cellulose, terpineol, ethylene glycol monobutyl ether, and ethylene glycol monobutyl ether acetate are stirred evenly to obtain an organic carrier solution; in step S14, the organic carrier solution is used to replace the suspension.

[0096] Comparative Example 3

[0097] This comparative example provides a resistor paste and a preparation method thereof, the difference from Example 1 is:

[0098] The resistor paste does not contain a thermal expansion coefficient regulator.

[0099] Preparation method of resistor paste. In step S12, ruthenium dioxide powder, bismuth ruthenate powder, lead ruthenate powder and RuO2 powder are added to a high-speed mixer and stirred evenly to obtain a mixed powder material.

[0100] Comparative Example 4

[0101] This comparative example provides a resistor paste and its preparation method. The difference from Example 1 is:

[0102] The resistor paste does not contain a sintering activator (RuO2 powder).

[0103] Preparation method of resistor paste. In step S12, ruthenium dioxide powder, bismuth ruthenate powder, lead ruthenate powder, Al2O3 powder, Si3N4 powder and B2O3 powder are added to a high-speed mixer and stirred evenly to obtain a mixed powder material.

[0104] Relevant performance test and analysis:

[0105] 1. Use the blade fineness method to test the fineness of the resistor pastes provided in Examples 1 to 7 and Comparative Examples 1 to 4.

[0106] 2. Use a rotational viscometer to test the viscosity of the resistor pastes provided in Examples 1 to 7 and Comparative Examples 1 to 4.

[0107] 3. Print the resistor pastes provided in Examples 1 to 7 and Comparative Examples 1 to 4 on a substrate respectively, and then sinter in air at 800 °C to form resistors.

[0108] (1) Use a resistance tester to test the resistance temperature coefficient (HTCR) in the high-temperature range and the resistance temperature coefficient (CTCR) in the low-temperature or below-room-temperature range of the resistors.

[0109] (2) Short-time overload test, that is, detect the stability and anti-damage ability of the resistor when it bears a load exceeding the rated power in a short time. Specifically, apply a load of 6.25 times the rated power to the resistor, and the overload time is 5 s. After the overload test is completed, place it in a standard environment for 1 h, and detect the resistance change; calculate the resistance change amount ΔR / R and judge whether it is within the range of ±0.5% to ±1%;

[0110] (3) High-temperature storage test, that is, detect the performance stability and reliability of the resistor in a long-term high-temperature environment. Specifically, place the sample in a high-temperature environment of 125 °C or 175 °C for 1000 h, and take samples to detect the resistance value every 250 h during the storage process; after the storage is completed, let the sample stand at room temperature for 1 to 2 h, and detect the resistance change; calculate the resistance change amount ΔR / R and judge whether it is within the range of ±0.5% to ±2%.

[0111] (4)Power load test, that is, to test the aging and stability of the resistor under the condition of long-term rated power load. Specifically, at an ambient temperature of 70 °C or 85 °C, continuously apply a load of rated power or close to rated power; adopt a periodic on-off test method, such as power on for 1.5 h and power off for 0.5 h, and cycle for a cumulative test of 1000 h; after the test is completed, let it stand at room temperature for 1 - 2 h, and detect the resistance change. Calculate the resistance change amount ΔR / R and judge whether it is within the range of ±1% to ±3%.

[0112] The test results are shown in Table 1 below:

[0113] Table 1

[0114]

[0115] As can be seen from Table 1, the fineness, viscosity, HTCR, CTCR, short-term overload, high-temperature storage and power load of the resistor pastes provided in Embodiments 1 - 7 of the present application all meet the national standard requirements and are even better than the national standard, indicating that the resistor pastes in the embodiments of the present application can meet the application requirements.

[0116] The HTCR, CTCR, short-term overload, high-temperature storage and power load of the resistor paste provided in Embodiment 1 are significantly better than those of Comparative Examples 1 - 4, indicating that the resistor formed by sintering the resistor paste in the embodiments of the present application under the synergistic effect of the temperature coefficient regulator, thermal expansion coefficient regulator and sintering activator has strong anti-damage ability, good long-term high-temperature stability, better reliability and a wider applicable range.

[0117] The HTCR and CTCR of the resistor paste provided in Embodiment 1 are significantly better than the national standard and are significantly better than those of Embodiments 2, 3 and Comparative Examples 1, 2, indicating that the positive temperature coefficient regulator and negative temperature coefficient regulator added to the resistor paste in the embodiments of the present application can significantly reduce the resistance temperature coefficient of the resistor paste.

[0118] The short-term overload and power load of the resistor paste provided in Embodiment 1 are significantly better than those of Embodiments 4 and 5, indicating that the resistor paste in the embodiments of the present application can better reduce the thermal expansion coefficient of the resistor paste and has better compatibility with the substrate under the synergistic effect of Al2O3 powder, Si3N4 powder and B2O3 powder, so as to have better anti-damage ability and long-term stability.

[0119] The HTCR, CTCR, short-term overload, high-temperature storage, and power load of the resistor paste provided in Example 1 are superior to those in Example 7, indicating that in the process of preparing the resistor paste in the embodiments of the present application, the LaMnO3 powder, MoO3 powder, and ZrO2 powder are first calcined to synthesize a composite oxide with a specific perovskite structure, and the NiMn2O4 powder, SnO2 powder, and Fe2O3 powder are calcined to synthesize a composite oxide with a specific spinel structure, and then mixed with the organic system, which can optimize the linear regulation ability of the resistance temperature coefficient and improve the long-term stability of the resistor body.

[0120] From Figure 1 The SEM of [the resistor paste] shows that the resistor paste provided in Example 1 is evenly dispersed, and the size of all solid-phase particles is below 10 microns, without obvious agglomeration, indicating that the resistor paste provided in the embodiments of the present application can form a dense and stable resistor after sintering.

[0121] The above are only the preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A resistive paste, characterized in that, It comprises components in the following parts by weight: 70 to 112 parts of conductive phase material, 0.1 to 3 parts of temperature coefficient regulator, 0.1 to 2 parts of thermal expansion coefficient regulator, 0.1 to 5 parts of sintering activator, 2 to 5 parts of glass powder, and 14 to 41 parts of organic carrier; Among them, the thermal expansion coefficient regulator comprises Al2O3, Si3N4 and B2O3 with a mass ratio of (75 to 95):(5 to 10):(0.1 to 5); The temperature coefficient regulator comprises a positive temperature coefficient regulator and a negative temperature coefficient regulator with a mass ratio of (1 to 9):(1 to 9); The steps for preparing the positive temperature coefficient regulator include: weighing appropriate amounts of LaMnO3 powder, MoO3 powder, ZrO2 powder, ethylene glycol, N-vinylpyrrolidone and diethylene glycol butyl ether acetate according to the mass ratio of LaMnO3, MoO3, ZrO2, ethylene glycol, N-vinylpyrrolidone and diethylene glycol butyl ether acetate being (1 to 10):(20 to 50):(1 to 10):(1 to 10):(1 to 10):(10 to 30); calcining the LaMnO3 powder, MoO3 powder and ZrO2 powder at 400 to 600 °C for 2 to 6 h to form a first composite oxide; mixing and treating the first composite oxide, ethylene glycol, N-vinylpyrrolidone and diethylene glycol butyl ether acetate to obtain the positive temperature coefficient regulator; The steps for preparing the negative temperature coefficient regulator include: weighing appropriate amounts of NiMn2O4 powder, SnO2 powder, Fe2O3 powder, ethylene glycol, N-vinylpyrrolidone and diethylene glycol butyl ether acetate according to the mass ratio of NiMn2O4, SnO2, Fe2O3, ethylene glycol, N-vinylpyrrolidone and diethylene glycol butyl ether acetate being (10 to 20):(1 to 10):(20 to 50):(1 to 10):(1 to 10):(10 to 30); calcining the NiMn2O4 powder, SnO2 powder and Fe2O3 powder at 400 to 600 °C for 2 to 6 h to form a second composite oxide; mixing and treating the second composite oxide, ethylene glycol, N-vinylpyrrolidone and diethylene glycol butyl ether acetate to obtain the negative temperature coefficient regulator.

2. The resistor paste according to claim 1, wherein The sintering activator is selected from at least one of nano-sized RuO2 powder, nano-sized ZrO2 powder and nano-sized CuO powder.

3. The resistor paste according to claim 2, characterized in that, The conductive phase material includes ruthenium-containing mixture powder.

4. The resistor paste according to claim 3, wherein, The ruthenium-containing mixture powder includes 45 to 68 parts of ruthenium dioxide powder, 15 to 24 parts of bismuth ruthenate powder and 10 to 20 parts of lead ruthenate powder; And / or, the organic carrier includes 5 to 10 parts of ethyl cellulose, 2 to 8 parts of terpineol, 2 to 8 parts of ethylene glycol monobutyl ether and 5 to 15 parts of ethylene glycol monobutyl ether acetate.

5. The resistor paste according to claim 4, wherein, The particle sizes of the ruthenium dioxide powder, bismuth ruthenate powder and lead ruthenate powder are 0.1 to 5 μm; And / or, the particle sizes of the nano-sized RuO2 powder, nano-sized ZrO2 powder and nano-sized CuO powder are 10 to 300 nm.

6. The resistor paste according to any one of claims 1 to 5, characterized in that The fineness of the resistance paste is ≤10 μm, the viscosity is 50 to 300 Pa·s, and the temperature coefficient is in the range of ±50 ppm / °C; And / or, the particle size of the glass powder is 0.5 to 3 μm.

7. A method for preparing a resist paste according to any one of claims 1 to 6, characterized in that, Comprising the following steps: Pre-mixing a conductive phase material, a thermal expansion coefficient regulator, and a sintering activator to obtain a mixed powder; Adding a temperature coefficient regulator to an organic carrier for mixing treatment to obtain a suspension; Adding the mixed powder and the glass powder to the suspension for dispersion treatment, and then performing three-roll ball milling treatment, and filtering to obtain a resistor paste.

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