An antioxidant solder material for semiconductor packaging and its preparation method

Abstract

This application relates to the field of solder materials technology, and more particularly to an antioxidant solder material for semiconductor packaging and its preparation method. An antioxidant solder material for semiconductor packaging, by weight, comprises the following raw materials: 83-88 parts of modified solder alloy powder, 7-10 parts of flux, and 3-5 parts of composite dispersant, wherein the modified solder alloy powder is obtained by modifying solder alloy powder with a silane coupling agent. The antioxidant solder material for semiconductor packaging of this application exhibits excellent performance in terms of antioxidant properties, low slag production rate, wettability, and environmental friendliness, and its preparation process is simple and efficient, possessing high practical value.

Description

Technical Field

[0001] This application relates to the field of solder materials technology, and in particular to an antioxidant solder material for semiconductor packaging and its preparation method. Background Technology

[0002] Currently, the solder alloys widely used in the semiconductor packaging field mainly include Sn-Pb and Sn-Ag-Cu systems. However, with increasingly stringent environmental protection requirements, lead-free solder is gradually becoming the mainstream. However, lead-free solder generally suffers from problems such as high melting point, poor wettability, and poor mechanical properties. Especially when dealing with the heat dissipation requirements of high-frequency and high-speed signal transmission and high-power devices, existing lead-free solder materials often fail to meet the dual requirements of high strength and good thermal conductivity.

[0003] Tin possesses excellent properties such as softness, low melting point, good ductility, strong plasticity, and non-toxicity, allowing it to be combined with many substances to form alloys with diverse properties and wide applications. In the electronics manufacturing industry, tin-lead solder and lead-free solder account for 70% of tin usage in processes such as manual dip soldering, wave soldering, automated soldering, and surface mount technology. Due to the significant environmental and human health impacts of the highly toxic nature of lead and its compounds, the demand for replacing tin-lead solder with lead-free solder is becoming increasingly urgent. However, existing lead-free solders are prone to producing tin oxide dross when used at high temperatures, affecting the soldering process and product quality, and increasing usage costs. Summary of the Invention

[0004] The purpose of this application is to address the shortcomings of current technologies by providing an antioxidant solder material for semiconductor packaging and its preparation method. The antioxidant solder material for semiconductor packaging of this application exhibits high antioxidant performance, low slag production rate, good wettability, and is non-toxic and harmless. Adding trace amounts of phosphorus and germanium has no significant effect on the melting temperature of the solder material, but reduces slag production and improves the antioxidant properties. Further compounding with antioxidants can significantly enhance the antioxidant properties of the solder material. Moreover, the preparation method of this application is simple, has high production efficiency, and low cost.

[0005] In a first aspect, this application provides an antioxidant solder material for semiconductor packaging, which adopts the following technical solution: an antioxidant solder material for semiconductor packaging, comprising the following raw materials by mass: 83-88 parts of modified solder alloy powder, 7-10 parts of flux, and 3-5 parts of composite dispersant, wherein the modified solder alloy powder is obtained by modifying solder alloy powder with a silane coupling agent.

[0006] By adopting the above technical solution, the antioxidant semiconductor packaging solder material is composed of modified solder alloy powder, flux, and composite dispersant. Each component plays a key role in the material's performance: Modified solder alloy powder: Modified with a silane coupling agent, the dispersibility and compatibility of the solder alloy powder in the flux are improved. This not only enhances the antioxidant properties of the solder material but also reduces slag production and improves wetting properties. Flux: Mainly composed of rosin and liquid maple. Rosin exhibits excellent antioxidant properties at high temperatures, rapidly removing the oxide film from the surface of the solder and base material in a molten state, while forming a protective film on its surface to prevent metal re-oxidation. Liquid maple releases volatile oils at high temperatures, effectively isolating air from contacting the solder surface and further inhibiting oxide film formation. The synergistic effect of the two significantly improves the overall antioxidant effect of the resin. Composite dispersant: Optimizes the mixing uniformity of each component, thereby improving the overall performance of the material. In summary, the careful combination and modification of these components significantly improve the overall performance of solder materials, meeting the stringent material requirements of semiconductor packaging processes.

[0007] Preferably, the solder alloy powder comprises the following components by weight percentage: 6-8% zinc, 1-2% nickel, 0.5-1% copper, 0.06-0.08% germanium, 0.01-0.02% phosphorus, with the balance being tin; the particle size of the solder alloy powder is 5-10 μm.

[0008] By adopting the above technical solution, adding trace amounts of phosphorus and germanium has no significant effect on the melting temperature of solder materials, but reduces the amount of slag produced and improves the oxidation resistance of solder materials. Furthermore, by compounding antioxidants, the oxidation resistance of solder materials can be significantly improved.

[0009] Preferably, the modified solder alloy powder is prepared by dispersing 100-150 parts of solder alloy powder in a solution composed of 200 parts of ethanol and 50 parts of water according to the mass ratio, then adding 2 parts of vinyltriethoxysilane to adjust the pH of the solution to 4, stirring the reaction for 4-5 hours, and then centrifuging, washing and drying to obtain the modified solder alloy powder.

[0010] By adopting the above technical solution, solder alloy powder is prepared by modifying it with silane coupling agent, which can significantly improve the dispersibility and compatibility of solder alloy powder in flux, thereby improving the oxidation resistance, low slag production rate and wetting performance of solder materials.

[0011] Preferably, the composite dispersant is composed of vinyl bis-stearamide, polyacrylamide dimethyl taurate ammonium and oleyl alcohol polyoxyethylene ether in a mass ratio of 1:2:1-3.

[0012] By employing the above technical solutions, the composite dispersant improves the dispersibility and compatibility of solder materials in flux, thereby enhancing the solder material's antioxidant properties, low slag production rate, and wetting performance. Vinyl bis-stearamide is a commonly used surfactant with excellent emulsifying, dispersing, and wetting properties. In this application, it helps solder alloy powder to be better dispersed in flux, improving the wettability and spread of the solder material. Ammonium polyacrylamide dimethyl taurate is an anionic surfactant with good water solubility and stability. In this application, it can synergistically work with vinyl bis-stearamide to further improve the dispersibility and compatibility of solder materials in flux. Oleyl alcohol polyoxyethylene ether is a nonionic surfactant with excellent emulsifying, dispersing, and wetting properties. In this application, it can work together with vinyl bis-stearamide and ammonium polyacrylamide dimethyl taurate to further improve the dispersibility and compatibility of solder materials in flux. In summary, the composite dispersant in this application significantly improves the dispersibility and compatibility of solder materials in flux through the synergistic effect of vinyl bis-stearamide, polyacrylamide dimethyl taurate ammonium, and oleyl alcohol polyoxyethylene ether, thereby enhancing the antioxidant properties, low slag production rate, and wetting properties of the solder materials.

[0013] Preferably, the flux comprises, by weight, the following raw materials: 25-30 parts rosin, 3-4 parts liquid styrax, 12-15 parts activator, 1-2 parts antioxidant, 2-3 parts surfactant, 0.5-0.8 parts corrosion inhibitor, and 38-45 parts solvent.

[0014] By employing the above technical solutions, rosin, a natural resin, possesses excellent antioxidant and wettability properties. At high temperatures, rosin can rapidly remove the oxide film from the surface of solder and base material, forming a protective film on the solder material surface to prevent metal re-oxidation. This helps inhibit the formation of an oxide film on the solder surface, allowing the solder material to maintain good soldering activity even under continuous high-temperature baking. Liquid maple contains volatile oils, which can be released at high temperatures, effectively isolating the contact between air and the solder surface, thereby inhibiting oxide film formation. The synergistic effect of liquid maple and rosin enhances the overall antioxidant effect, more effectively removing solder slag and oxide film. Activators have excellent antioxidant properties, significantly reducing slag production and exhibiting less corrosivity to solder and welding materials. Simultaneously, activators can improve the wettability and spread rate of solder, helping the solder material to better wet the solder joint and improve welding quality. Antioxidants are used to further improve the antioxidant performance of solder materials. By adding trace amounts of elements such as phosphorus and germanium, the antioxidant properties of solder materials can be significantly improved without significantly affecting the melting temperature. Surfactants reduce the surface tension of solder materials, improving their wettability and spreadability. This helps the solder material better cover the solder joints, improving soldering quality. Corrosion inhibitors protect the solder and welding materials from corrosion, extending their service life. The presence of corrosion inhibitors reduces corrosion during use, maintaining the stability and reliability of the solder joint. Solvents dissolve and dilute other components in the flux, ensuring uniform distribution and ease of application. The selection of solvents should consider their volatility and safety to ensure the safety and environmental friendliness of the flux during use. In summary, the flux in this application, through the combined action of its components, not only possesses excellent antioxidant properties and low slag production, but also good wettability and non-toxicity. This flux can significantly improve the soldering quality and reliability of solder materials, making it suitable for demanding semiconductor packaging applications.

[0015] Preferably, the activator is composed of dimer fatty acids and succinic acid in a mass ratio of 4:1-3.

[0016] By adopting the above technical solutions, dimer fatty acids exhibit excellent wettability, significantly improving the fluidity and coverage of solder materials during the soldering process, ensuring sufficient wetting of solder joints and thus improving soldering quality. Dimer fatty acids can reduce the surface tension of solder materials, making them easier to spread on the soldering surface and reducing slag formation. Dimer fatty acids possess certain antioxidant properties, slowing down solder oxidation at high temperatures and extending the service life of solder materials. Succinic acid has an activating effect, rapidly removing oxides from the solder and base material surfaces, ensuring direct metal-to-metal contact during soldering and improving soldering strength. At high temperatures, succinic acid promotes the melting of solder materials, lowering their melting point and making the soldering process smoother. Succinic acid also possesses certain antioxidant properties, working synergistically with dimer fatty acids to further enhance the antioxidant capacity of solder materials. The combined effect of dimer fatty acids and succinic acid significantly improves the wettability and fluidity of solder materials, ensuring sufficient wetting of solder joints and reducing soldering defects. The synergistic antioxidant effect of both effectively slows down the oxidation rate of solder materials at high temperatures, reducing slag formation and improving soldering quality. By activating solder joints and acting as a flux, dimer fatty acids and butyric acid jointly improve the strength and reliability of the solder joint. This combination of activators not only enhances the wettability and oxidation resistance of the solder material but also strengthens its stability and service life at high temperatures. In summary, the combination of dimer fatty acids and butyric acid plays a crucial role as an activator in the solder material of this application, significantly improving its overall performance through synergistic effects, making it suitable for demanding semiconductor packaging applications.

[0017] Preferably, the antioxidant is composed of ethoxyquinoline, tert-butylhydroquinone, and butylated hydroxytoluene in a mass ratio of 4:5:1-3.

[0018] By employing the above technical solutions, this combination of antioxidants plays multiple roles in solder materials, and there is a synergistic effect between ethoxyquinoline, tert-butylhydroquinone (TBHQ), and butylated hydroxytoluene (BHT), collectively enhancing the antioxidant performance of the solder materials. Ethoxyquinoline is a highly efficient antioxidant, effectively capturing free radicals, slowing down the oxidation reaction, and extending the service life of the solder materials. Ethoxyquinoline exhibits good thermal stability, maintaining its antioxidant properties at high temperatures, making it suitable for high-temperature soldering processes in semiconductor packaging. Ethoxyquinoline has good compatibility with other components and can be uniformly dispersed in the solder materials to exert its antioxidant effect. Tert-butylhydroquinone (TBHQ) is a powerful free radical scavenger, effectively preventing the propagation of the oxidation reaction chain and protecting the solder materials from oxidation. TBHQ maintains good antioxidant properties even at high temperatures, ensuring that the solder materials are not easily oxidized during high-temperature soldering. The combined effect of TBHQ and other antioxidants significantly enhances the overall antioxidant effect. Butylated hydroxytoluene (BHT) is also a commonly used antioxidant that can synergistically enhance its antioxidant effect with ethoxyquinoline and TBHQ. BHT exhibits good thermal stability, remaining stable at high temperatures and making it suitable for high-temperature soldering environments. BHT is compatible with other components in solder materials and will not negatively impact material performance. The combined effects of ethoxyquinoline, tert-butylhydroquinone, and butylated hydroxytoluene include: 1. Synergistic Antioxidant Effect: These three antioxidants work together to form a powerful antioxidant system, effectively capturing free radicals, slowing down oxidation reactions, and significantly improving the antioxidant performance of solder materials. 2. High-Temperature Stability: All three antioxidants maintain good stability and antioxidant performance at high temperatures, ensuring that solder materials are not easily oxidized during high-temperature soldering. 3. Comprehensive Performance Improvement: Through synergistic effects, these three antioxidants not only improve the antioxidant performance of solder materials but also enhance their stability and service life at high temperatures. 4. Reduced Slag Production: The presence of antioxidants reduces oxidation of solder materials during the soldering process, thereby reducing slag production and improving soldering quality and reliability. In summary, the combination of ethoxyquinoline, tert-butylhydroquinone, and butylated hydroxytoluene plays an important role as an antioxidant in the solder material of this application. Through synergistic effects, it significantly improves the antioxidant properties and overall performance of the solder material, making it suitable for demanding semiconductor packaging applications.

[0019] Preferably, the surfactant is composed of fatty alcohol polyoxyethylene ether and alkylphenol polyoxyethylene ether in a mass ratio of 4:1-3.

[0020] By adopting the above technical solution, the surfactant is composed of fatty alcohol polyoxyethylene ether (AEO) and alkylphenol polyoxyethylene ether (APEO) in a mass ratio of 4:1-3. This combination of surfactants plays multiple roles in solder materials, and there is a synergistic effect between fatty alcohol polyoxyethylene ether and alkylphenol polyoxyethylene ether, which jointly improves the performance of the solder material. AEO has good wetting properties, which can reduce the surface tension between the solder material and the soldering surface, improve the wettability of the solder, and ensure that the solder joint is formed more uniformly and firmly. AEO can help the solder alloy powder to be better dispersed in the flux, avoiding powder agglomeration, thereby improving the consistency and reliability of the solder material. AEO can improve the stability of the solder material during storage and use, and prevent component separation or precipitation. APEO has excellent emulsifying properties, which can help the oil-soluble components and water-soluble components in the flux to mix better to form a stable emulsion, improving the overall effect of the flux. APEO has good cleaning ability, which can effectively remove oxides and other contaminants from the soldering surface, ensuring the cleanliness of the soldering surface and improving the soldering quality. The combined effects of fatty alcohol polyoxyethylene ether (AEO) and alkylphenol polyoxyethylene ether (APEO): 1. Synergistic wetting: The combined action of AEO and APEO significantly improves the wetting performance of solder materials, ensuring that the solder fully wets the soldering surface during the soldering process, forming high-quality solder joints. 2. Enhanced dispersibility: The synergistic effect of these two surfactants further improves the dispersibility of solder alloy powder in flux, preventing powder agglomeration and improving the uniformity and reliability of solder materials. 3. Stability and compatibility: The synergistic effect of AEO and APEO enhances the stability of solder materials during storage and use, preventing component separation or precipitation, while ensuring the compatibility of solder materials with the soldering surface. 4. Comprehensive cleaning effect: The cleaning ability of APEO combined with the wetting properties of AEO can more effectively remove oxides and other contaminants from the soldering surface, improving soldering quality. In summary, the combination of fatty alcohol polyoxyethylene ether and alkylphenol polyoxyethylene ether, as surfactants, plays an important role in the tin materials of this application, significantly improving the wettability, dispersibility, and stability of the solder materials through synergistic effects, making them suitable for demanding semiconductor packaging applications.

[0021] Preferably, the corrosion inhibitor is benzotriazole; and the solvent is diethylene glycol monohexyl ether.

[0022] Secondly, this application provides a method for preparing an antioxidant solder material for semiconductor packaging, which adopts the following technical solution:

[0023] As a general technical concept, this application also provides a method for preparing the above-mentioned antioxidant semiconductor packaging solder material, including the following steps:

[0024] S101. Add the solvent to the container according to the mass fraction, heat to 120°C, then add rosin and stir until the rosin is completely dissolved to obtain a rosin solution.

[0025] S102. According to the mass fraction, lower the temperature of the rosin solution to 60-65℃, add liquid styrax, activator, antioxidant, surfactant and corrosion inhibitor, maintain the temperature and stir at 300-400r / min for 20-30 minutes to obtain flux;

[0026] S103. According to the mass fraction, add the modified solder alloy powder and composite dispersant to the flux in sequence and mix. Stir at a speed of 1000-1200 r / min for 30-40 min. Place in a mold and quickly lower the temperature to 5℃ for molding and cold storage to obtain the anti-oxidation semiconductor packaging solder material.

[0027] In summary, the beneficial technical effects of this application are as follows:

[0028] 1. High oxidation resistance: The modified solder alloy powder is modified with a silane coupling agent, which improves the dispersibility and compatibility of the solder alloy powder in the flux, thereby enhancing the oxidation resistance of the solder material. In addition, the addition of trace amounts of phosphorus and germanium, along with the formulation of antioxidants, further enhances the oxidation resistance of the solder material.

[0029] 2. Low slag production rate: The addition of trace amounts of phosphorus and germanium significantly reduces the amount of slag produced. At the same time, the activators in the flux also exhibit excellent antioxidant effects, which significantly reduces the amount of slag produced.

[0030] 3. Good wettability: The optimized combination of modified solder alloy powder and flux gives the solder material good wettability, which helps to improve soldering quality and reliability.

[0031] 4. Non-toxic and harmless: All materials used are non-toxic and harmless, meet environmental protection requirements, and are suitable for various semiconductor packaging applications.

[0032] 5. Efficient preparation method: The preparation method of this application is simple, has high production efficiency and low cost, and is suitable for large-scale industrial production. Detailed Implementation

[0033] The embodiments of this application will be described in detail below with reference to examples. However, those skilled in the art will understand that the following examples are for illustrative purposes only and should not be considered as limiting the scope of this application. Unless otherwise specified in the examples, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all commercially available conventional products.

[0034] In the following examples and preparation examples, 1 part represents 100g.

[0035] Preparation Example 1: Preparation of Modified Solder Alloy Powder

[0036] Solder alloy powder comprises the following components by weight percentage: 7% zinc, 1.2% nickel, 0.9% copper, 0.07% germanium, 0.015% phosphorus, with the balance being tin; the particle size of the solder alloy powder is 5-10 μm.

[0037] The modified solder alloy powder is prepared by dispersing 120 parts of solder alloy powder in a solution consisting of 200 parts of ethanol and 50 parts of water according to the mass ratio, then adding 2 parts of vinyltriethoxysilane to adjust the pH of the solution to 4, stirring and reacting for 4.5 hours, and then centrifuging, washing and drying to obtain the modified solder alloy powder.

[0038] Preparation of solder alloy powder in Comparative Example 1

[0039] Solder alloy powder comprises the following components by weight percentage: 7% zinc, 1.2% nickel, 0.9% copper, 0.07% germanium, 0.015% phosphorus, with the balance being tin; the particle size of the solder alloy powder is 5-10 μm.

[0040] Preparation of Comparative Example 2: Preparation of Modified Solder Alloy Powder

[0041] Same as in Preparation Example 1, except that: germanium 0% and phosphorus 0%.

[0042] Example 1

[0043] An antioxidant solder material for semiconductor packaging, by weight, comprises the following raw materials: 83 parts modified solder alloy powder, 7 parts flux, and 3 parts composite dispersant, wherein the composite dispersant is composed of vinyl bis-stearamide, polyacrylamide dimethyl taurate ammonium, and oleyl alcohol polyoxyethylene ether in a weight ratio of 1:2:1; the flux, by weight, comprises the following raw materials: 25 parts rosin, 3 parts liquid styrax, 12 parts activator, 1 part antioxidant, 2 parts surfactant, 0.5 parts benzotriazole, and 38 parts diethylene glycol monohexyl ether, wherein the activator is composed of dimer fatty acid and succinic acid in a weight ratio of 4:1, the antioxidant is composed of ethoxyquinoline, tert-butylhydroquinone, and butylated hydroxytoluene in a weight ratio of 4:5:1, and the surfactant is composed of fatty alcohol polyoxyethylene ether and alkylphenol polyoxyethylene ether in a weight ratio of 4:1.

[0044] The preparation method of the above-mentioned antioxidant semiconductor packaging solder material includes the following steps:

[0045] S101. According to the mass fraction, add diethylene glycol monohexyl ether to a container, heat to 120°C, then add rosin and stir until the rosin is completely dissolved to obtain a rosin solution.

[0046] S102. According to the mass fraction, lower the temperature of the rosin solution to 60°C, add liquid styrax, activator, antioxidant, surfactant and benzotriazole, maintain the temperature and stir at 300 r / min for 30 minutes to obtain flux;

[0047] S103. According to the mass fraction, add the modified solder alloy powder and composite dispersant to the flux in sequence and mix. Stir at 1000 r / min for 40 min. Place in a mold and quickly lower the temperature to 5℃ for molding and cold storage to obtain the anti-oxidation semiconductor packaging solder material.

[0048] Example 2

[0049] An antioxidant solder material for semiconductor packaging, by weight, comprises the following raw materials: 88 parts modified solder alloy powder, 10 parts flux, and 5 parts composite dispersant, wherein the composite dispersant is composed of vinyl bis-stearamide, polyacrylamide dimethyl taurate ammonium, and oleyl alcohol polyoxyethylene ether in a weight ratio of 1:2:3; the flux, by weight, comprises the following raw materials: 30 parts rosin, 4 parts liquid styrax, 15 parts activator, 2 parts antioxidant, 3 parts surfactant, 0.8 parts benzotriazole, and 45 parts diethylene glycol monohexyl ether, wherein the activator is composed of dimer fatty acid and succinic acid in a weight ratio of 4:3, the antioxidant is composed of ethoxyquinoline, tert-butylhydroquinone, and butylated hydroxytoluene in a weight ratio of 4:5:3, and the surfactant is composed of fatty alcohol polyoxyethylene ether and alkylphenol polyoxyethylene ether in a weight ratio of 4:3.

[0050] The preparation method of the above-mentioned antioxidant semiconductor packaging solder material includes the following steps:

[0051] S101. According to the mass fraction, add diethylene glycol monohexyl ether to a container, heat to 120°C, then add rosin and stir until the rosin is completely dissolved to obtain a rosin solution.

[0052] S102. According to the mass fraction, lower the temperature of the rosin solution to 65°C, add liquid styrax, activator, antioxidant, surfactant and benzotriazole, maintain the temperature and stir at 400 r / min for 20 minutes to obtain flux;

[0053] S103. According to the mass fraction, add the modified solder alloy powder and composite dispersant to the flux in sequence and mix. Stir at 1200 r / min for 30 min. Place in a mold and quickly lower the temperature to 5℃ for molding and cold storage to obtain the anti-oxidation semiconductor packaging solder material.

[0054] Example 3

[0055] An antioxidant solder material for semiconductor packaging, by weight, comprises the following raw materials: 85 parts modified solder alloy powder, 9 parts flux, and 4 parts composite dispersant, wherein the composite dispersant is composed of vinyl bis-stearamide, polyacrylamide dimethyl taurate ammonium, and oleyl alcohol polyoxyethylene ether in a weight ratio of 1:2:2; the flux, by weight, comprises the following raw materials: 28 parts rosin, 3.4 parts liquid styrax, 13 parts activator, 1.2 parts antioxidant, 2.3 parts surfactant, 0.7 parts benzotriazole, and 41 parts diethylene glycol monohexyl ether, wherein the activator is composed of dimer fatty acid and succinic acid in a weight ratio of 4:2, the antioxidant is composed of ethoxyquinoline, tert-butylhydroquinone, and butylated hydroxytoluene in a weight ratio of 4:5:2, and the surfactant is composed of fatty alcohol polyoxyethylene ether and alkylphenol polyoxyethylene ether in a weight ratio of 4:2.

[0056] The preparation method of the above-mentioned antioxidant semiconductor packaging solder material includes the following steps:

[0057] S101. According to the mass fraction, add diethylene glycol monohexyl ether to a container, heat to 120°C, then add rosin and stir until the rosin is completely dissolved to obtain a rosin solution.

[0058] S102. According to the mass fraction, lower the temperature of the rosin solution to 63°C, add liquid styrax, activator, antioxidant, surfactant and benzotriazole, maintain the temperature and stir at 350 r / min for 25 minutes to obtain flux;

[0059] S103. According to the mass fraction, add the modified solder alloy powder and composite dispersant to the flux in sequence and mix. Stir at 1100 r / min for 35 min. Place in a mold and quickly lower the temperature to 5℃ for molding and cold storage to obtain the anti-oxidation semiconductor packaging solder material.

[0060] Comparative Example 1

[0061] Similar to Example 3, except that an equal amount of the solder alloy powder prepared in Comparative Example 1 was used instead of the modified solder alloy powder.

[0062] Comparative Example 2

[0063] Similar to Example 3, except that an equal amount of the modified solder alloy powder prepared in Comparative Example 2 was used instead of the modified solder alloy powder.

[0064] Comparative Example 3

[0065] Similar to Example 3, except that the composite dispersant is vinyl bis-stearamide.

[0066] Comparative Example 4

[0067] Similar to Example 3, except that the composite dispersant is ammonium polyacrylamide dimethyl taurate.

[0068] Comparative Example 5

[0069] Similar to Example 3, except that the composite dispersant is oleyl alcohol polyoxyethylene ether.

[0070] Comparative Example 6

[0071] Similar to Example 3, except that the activator is a dimer fatty acid.

[0072] Comparative Example 7

[0073] Same as in Example 3, except that the active agent is succinic acid.

[0074] Comparative Example 8

[0075] Same as in Example 3, except that the antioxidant is ethoxyquinoline.

[0076] Comparative Example 9

[0077] Same as in Example 3, except that the antioxidant is tert-butylhydroquinone.

[0078] Comparative Example 10

[0079] Same as in Example 3, except that the antioxidant is butylated hydroxytoluene.

[0080] Performance testing

[0081] Samples of the antioxidant semiconductor packaging solder materials prepared in Examples 1-3 and Comparative Examples 1-10 were taken and made into solder bars for performance testing.

[0082] Melting point: The melting temperature of the solder alloy was measured using a Diamondosc differential scanning calorimeter. The mass of the sample was approximately 10 mg, the test temperature range was 50-450℃, and the heating rate was 10℃ / min.

[0083] Wetting angle: determined using the IPC-TM-6502.4.45 test method;

[0084] Spreadability determination: Measured using the IPC-TM-6502.4.35 test method;

[0085] Antioxidant properties: Antioxidant properties were tested by static oxidation method. The furnace temperature was 270℃, the mass was 500g, the slag was scraped once every 60s, and the slag was taken once every 5min. Each group was tested 3 times, and the average value of the 3 tests was taken.

[0086] Corrosion resistance was determined using the IPC-TM-6502.6.15 test method.

[0087] Table 1 Performance Tests

[0088]

[0089]

[0090] Analyzing the data in Table 1, we can see that:

[0091] 1) The antioxidant solder materials for semiconductor packaging prepared in Examples 1-3 have high antioxidant properties, low slag production rate, good wetting angle and corrosion resistance.

[0092] 2) The performance comparison analysis of the antioxidant semiconductor packaging solder materials prepared in Example 3 and Comparative Example 1 shows that the solder alloy powder prepared by modification with silane coupling agent can significantly improve the dispersibility and compatibility of the solder alloy powder in the flux, thereby improving the antioxidant performance, low slag production rate and wetting performance of the solder material.

[0093] 3) The performance comparison analysis of the antioxidant semiconductor packaging solder materials prepared in Example 3 and Comparative Example 2 shows that the addition of trace amounts of phosphorus and germanium has no significant effect on the melting temperature of the solder material, but reduces the amount of slag produced and improves the antioxidant properties of the solder material. Furthermore, the addition of antioxidants can significantly improve the antioxidant properties of the solder material.

[0094] 4) The performance comparison analysis of the antioxidant semiconductor packaging solder materials prepared in Example 3 and Comparative Examples 3-5 shows that the composite dispersant is composed of vinyl bis-stearamide, polyacrylamide dimethyl taurate ammonium and oleyl alcohol polyoxyethylene ether in a mass ratio of 1:2:2. By utilizing their synergistic effect, the dispersibility and compatibility of the solder material in the flux are significantly improved, thereby improving the antioxidant performance, low slag production rate and wetting performance of the solder material.

[0095] 5) A comparative analysis of the performance of the antioxidant solder materials for semiconductor packaging prepared in Example 3 and Comparative Examples 6-7 shows that the activator, composed of dimer fatty acids and succinic acid in a mass ratio of 4:2, effectively slows down the oxidation rate of the solder material at high temperatures, reduces slag formation, and improves soldering quality through their synergistic effect. By activating the solder joint and acting as a flux, the dimer fatty acids and butyric acid jointly improve the strength and reliability of the solder joint. This combination of activators not only improves the wettability and antioxidant properties of the solder material but also enhances its stability and service life at high temperatures, significantly improving the overall performance of the solder material and making it suitable for demanding semiconductor packaging applications.

[0096] 6) The performance comparison analysis of the antioxidant solder materials for semiconductor packaging prepared in Example 3 and Comparative Examples 8-10 shows that the antioxidant is composed of ethoxyquinoline, tert-butylhydroquinone and dibutylhydroxytoluene in a mass ratio of 4:5:2. By utilizing their synergistic effect, the antioxidant significantly improves the antioxidant performance and overall performance of the solder material, making it suitable for high-requirement semiconductor packaging applications.

[0097] The above embodiments are only used to explain the technical solutions of this application and are not intended to limit it. Although the above embodiments have provided specific descriptions of this application, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of this invention. Any modifications and equivalent substitutions that do not depart from the spirit and scope of this application should be covered within the protection scope of this application.

Claims

1. An antioxidant solder material for semiconductor packaging, characterized in that, The preparation materials include the following raw materials by mass: 83-88 parts of modified solder alloy powder, 7-10 parts of flux, and 3-5 parts of composite dispersant, wherein the modified solder alloy powder is obtained by modifying solder alloy powder with a silane coupling agent; The solder alloy powder comprises the following components by weight percentage: zinc 6-8%, nickel 1-2%, copper 0.5-1%, germanium 0.06-0.08%, phosphorus 0.01-0.02%, with the balance being tin; the particle size of the solder alloy powder is 510μm. The modified solder alloy powder is prepared by dispersing 100-150 parts of solder alloy powder in a solution composed of 200 parts of ethanol and 50 parts of water according to the mass ratio, then adding 2 parts of vinyltriethoxysilane to adjust the pH of the solution to 4, stirring the reaction for 4-5 hours, and then centrifuging, washing and drying to obtain the modified solder alloy powder. The composite dispersant is composed of vinyl bis-stearamide, polyacrylamide dimethyl taurate ammonium, and oleyl alcohol polyoxyethylene ether in a mass ratio of 1:2:1-3.

2. The solder material for antioxidant semiconductor packaging according to claim 1, characterized in that, The flux, by weight, comprises the following raw materials: 25-30 parts rosin, 3-4 parts liquid styrax, 12-15 parts activator, 1-2 parts antioxidant, 2-3 parts surfactant, 0.5-0.8 parts corrosion inhibitor, and 38-45 parts solvent.

3. The solder material for antioxidant semiconductor packaging according to claim 2, characterized in that, The activator is composed of dimer fatty acids and succinic acid in a mass ratio of 4:1-3.

4. The anti-oxidation solder material for semiconductor packaging according to claim 2, characterized in that, The antioxidant is composed of ethoxyquinoline, tert-butylhydroquinone, and butylated hydroxytoluene in a mass ratio of 4:5:1-3.

5. The solder material for antioxidant semiconductor packaging according to claim 2, characterized in that, The surfactant is composed of fatty alcohol polyoxyethylene ether and alkylphenol polyoxyethylene ether in a mass ratio of 4:1-3.

6. The solder material for antioxidant semiconductor packaging according to claim 2, characterized in that, The corrosion inhibitor is benzotriazole; the solvent is diethylene glycol monohexyl ether.

7. A method for preparing an antioxidant semiconductor packaging solder material according to any one of claims 1-6, characterized in that, Includes the following steps: S101. Add the solvent to the container according to the mass fraction, heat to 120°C, then add rosin and stir until the rosin is completely dissolved to obtain a rosin solution. S102. According to the mass fraction, lower the temperature of the rosin solution to 60-65℃, add liquid styrax, activator, antioxidant, surfactant and corrosion inhibitor, maintain the temperature and stir at 300-400r / min for 20-30 minutes to obtain flux; S103. According to the mass fraction, add the modified solder alloy powder and composite dispersant to the flux in sequence and mix. Stir at a speed of 1000-1200 r / min for 30-40 min. Place in a mold and quickly lower the temperature to 5℃ for molding and cold storage to obtain the anti-oxidation semiconductor packaging solder material.

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