High-temperature-resistant active welding material for IGBT (insulated gate bipolar transistor) and preparation process thereof

Abstract

The invention relates to a high-temperature-resistant active welding material for an IGBT (Insulated Gate Bipolar Translator) and a preparation process of the high-temperature-resistant active welding material, and belongs to the technical field of welding materials. The high-lead solder paste comprises the following raw materials in percentage by weight: 95%-97% of Sn, 2%-4% of Pb and 0%-1% of YN. The lead-free solder comprises the following raw materials in percentage by weight: 95.5 percent to 96.5 percent of Sn, 3.0 percent to 3.8 percent of Ag and 0.5 percent to 0.7 percent of Cu. According to the high-temperature-resistant active welding material for the IGBT and the preparation technology of the high-temperature-resistant active welding material, the high-temperature-resistant active welding material prepared through reasonable proportion of the high-lead solder paste and the lead-free solder and selection of the specific soldering flux has the excellent high-temperature-resistant characteristic, performance reduction or failure of an IGBT module caused by failure of the welding material is effectively avoided, and the service life of the IGBT module is prolonged. The operation reliability of the IGBT module in a high-temperature environment is greatly improved, the service life of the IGBT module is prolonged, and the advantages of high temperature resistance, good activity and high welding quality are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of welding materials, in particular to a high-temperature resistant active welding material for IGBT and a preparation process thereof. Background Art

[0002] As a composite, fully controlled, voltage-driven power semiconductor device, the insulated gate bipolar transistor (IGBT) combines the high input impedance, low drive power consumption, and fast switching capabilities of a MOSFET with the high current carrying capacity and low on-state voltage drop of a BJT (bipolar transistor). IGBTs have broad application prospects in power electronics, including electric vehicles, home appliances, wind power generation equipment, solar power generation equipment, and rail transit traction. In rail transit, IGBTs are core components of the traction drive system and the "heart" of train operation.

[0003] With the booming development of emerging industries such as renewable energy power generation, rail transit, smart grids, and electric vehicles, IGBT devices have experienced unprecedented widespread application. The selection of soldering materials is crucial during the IGBT module packaging process. IGBT modules generate extremely high temperatures during operation, especially in high-power applications, where local temperatures within the module can reach 180°C or even 200°C. Furthermore, IGBT modules can be subject to adverse factors such as external humidity, heat, external impact, and intense mechanical vibration during operation on equipment such as high-speed trains. Therefore, the packaging materials for the next generation of high-power IGBT modules must exhibit excellent high-temperature resistance to ensure reliable operation of the IGBT chips.

[0004] Conventional soldering materials are prone to softening, deformation, and solder joint loss in high-temperature environments, leading to performance degradation or even failure of IGBT modules. Therefore, developing a high-temperature-resistant and highly active soldering material is crucial for improving the reliability and service life of IGBT modules. Summary of the Invention

[0005] In view of the shortcomings of the existing technology, the present invention provides a high-temperature resistant active welding material for IGBT and its preparation process, which has the advantages of high temperature resistance, good activity and high welding quality, and solves the problems raised by the above background technology.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A high-temperature resistant active solder material for IGBT, comprising high-lead solder paste, lead-free solder and flux;

[0008] The high-lead solder paste comprises the following raw materials in the following weight proportions:

[0009] Sn: 95%-97%, Pb: 2%-4%, YN: 0%-1%;

[0010] The lead-free solder comprises the following raw materials in the following weight proportions:

[0011] Sn: 95.5%-96.5%, Ag: 3.0%-3.8%, Cu: 0.5%-0.7%;

[0012] The soldering flux is any one of 891 soldering flux, no-clean soldering flux or rosin soldering flux;

[0013] The 891 soldering flux comprises the following raw materials in the following weight proportions:

[0014] Triethanolamine: 2%, benzene hydrochloride: 3%, industrial alcohol: 90%, rosin: 5%.

[0015] Furthermore, the high-lead solder paste also contains other trace metal elements, the total content of which does not exceed 0.1%, and the trace metal elements are used to improve specific properties of the solder paste.

[0016] Furthermore, the lead-free solder further comprises Ga element or Ge element, and the content of each element in weight percentage is respectively: Ga: 0.001-0.1%, Ge: 0.001-0.1%.

[0017] Furthermore, the no-clean soldering flux comprises the following raw materials in the following weight proportions:

[0018] Succinic acid: 1.5%, adipic acid: 1.0%, dibromobutenedioic acid: 0.2%, dibromobutenedioic acid: 0.68%, OP-10: 0.35%, FSN-100: 0.05%, ethanol balance.

[0019] Furthermore, when preparing the no-clean soldering flux, a proper amount of ethanol is poured into a glass container, and then various ingredients are added in sequence, and then stirred with an insulating rod until uniform.

[0020] Furthermore, the rosin-based soldering flux comprises the following raw materials in the following weight proportions:

[0021] Rosin: 25%, Alcohol: 75%.

[0022] Furthermore, the concentration of alcohol in the rosin-type soldering flux is 99.5%. When preparing the rosin-type soldering flux, rosin is dissolved in alcohol to form a uniform solution.

[0023] Another technical problem to be solved by the present invention is to provide a preparation process of a high-temperature resistant active solder material for IGBT, comprising the following steps:

[0024] S1. Raw material preparation: Prepare high-lead solder paste raw materials, lead-free solder raw materials, and flux raw materials according to the given weight ratios. Ensure that the purity and quality of the high-lead solder paste raw materials meet the requirements to avoid impurities affecting the performance of the soldering materials. Lead-free solder raw materials must undergo strict screening and testing to ensure that their composition is accurate and free of harmful impurities. Ensure that the industrial alcohol is of high purity and that the rosin is ground into a fine powder to improve the performance of the flux.

[0025] S2. Preparation of high-lead solder paste: Weighed Sn, Pb, and YN are placed in a melting furnace and smelted at a temperature of 300-350°C to fully melt and mix the raw materials. After smelting, the molten alloy liquid is poured into a mold for cooling. After cooling to room temperature, the formed high-lead solder paste is removed and then cut and ground as needed to achieve the desired shape and size.

[0026] S3. Preparation of lead-free solder: Weighed Sn, Ag, and Cu are placed in a smelting device and smelted at a temperature of 220-250°C. After smelting, the smelted alloy liquid is poured into a mold for cooling. After cooling to room temperature, the formed lead-free solder is removed and subsequently processed as needed to obtain the desired solder shape.

[0027] S4. Preparation of solder flux: Pour the weighed triethanolamine, benzene hydrochloride, and rosin powder into a glass container that is easy to stir; then pour industrial alcohol into the container and immediately stir the liquid with an insulating rod until the liquid is very uniform when viewed along the glass container under sunlight; finally, pour hot water into a porcelain basin and place the glass container in the basin. Continue to heat the water in the basin for 30 minutes, then remove the solution and use it;

[0028] S5. Mixing and blending: Mix the prepared high-lead solder paste, lead-free solder and flux in a certain proportion. During the mixing process, ensure that all ingredients are fully mixed to avoid local unevenness. Use a stirring device to stir. The stirring time and speed should be adjusted according to the characteristics of the mixture and the mixing requirements.

[0029] S6. Quality testing: Conduct various performance tests on the prepared high-temperature resistant active soldering materials for IGBT, including melting point, wettability, mechanical strength and high-temperature resistance; adjust and optimize the preparation process to ensure that the quality of the soldering materials meets the requirements;

[0030] S7. Packaging and storage: Pack the qualified welding materials and mark the product name, specifications, model, production date and shelf life on the packaging; store the packaged welding materials in a dry, cool and ventilated environment.

[0031] Furthermore, during the smelting process in S2, continuous stirring is required to ensure that the components are evenly distributed to avoid component segregation. During the smelting process in S3, continuous stirring is required to ensure that silver and copper are evenly dispersed in the tin matrix to form a uniform alloy. The solder in S3 includes solder wire and solder sheet.

[0032] Furthermore, the melting point test in S6 measures the melting point of the welding material by using a differential scanning calorimeter to ensure that it meets the requirements of IGBT welding; the wettability test in S6 measures the wetting angle of the welding material on the surface of the substrate by using a wetting angle measuring instrument. The smaller the wetting angle, the better the wettability, which is conducive to improving the welding quality; the mechanical strength test in S6 uses a tensile testing machine to perform a tensile test on the welding joint to detect its mechanical performance index of tensile strength; the high temperature resistance test in S6 places the welding material or welding joint in a high temperature environment, observes its performance changes at high temperature, observes whether it softens or deforms, and evaluates its high temperature resistance.

[0033] Compared with the prior art, the present invention provides a high-temperature resistant active welding material for IGBT and a preparation process thereof, which has the following beneficial effects:

[0034] 1. The high-temperature resistant active soldering material for IGBT and its preparation process are made by selecting a reasonable ratio of high-lead solder paste, lead-free solder and specific flux. The high-temperature resistant active soldering material has excellent high-temperature resistance. Compared with traditional soldering materials, this soldering material is less likely to soften or deform at high temperatures of 180°C or even 200°C, effectively avoiding the performance degradation or failure of the IGBT module caused by failure of the soldering material, greatly improving the operating reliability of the IGBT module in high-temperature environments, extending its service life, and reducing losses such as equipment downtime and maintenance costs caused by module failure, thereby achieving the advantages of high-temperature resistance, good activity and high welding quality.

[0035] 2. The high-temperature resistant active welding material for IGBT and its preparation process. The high-temperature resistant active welding material prepared by the above-mentioned preparation process can effectively improve the overall stability of the welding material, effectively improve the overall environmental performance of the welding material, and effectively improve the overall flexibility of the welding material, achieving the advantages of good stability and good environmental protection effect. DETAILED DESCRIPTION

[0036] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0037] Example 1:

[0038] A high-temperature resistant active solder material for IGBT, comprising high-lead solder paste, lead-free solder and flux;

[0039] High-lead solder paste includes the following raw materials in the following weight ratios:

[0040] Sn: 95%-97%, Pb: 2%-4%, YN: 0%-1%;

[0041] Lead-free solder includes the following raw materials in the following weight ratios:

[0042] Sn: 95.5%-96.5%, Ag: 3.0%-3.8%, Cu: 0.5%-0.7%;

[0043] The flux is any one of 891 flux, no-clean flux or rosin flux;

[0044] 891 soldering flux consists of the following raw materials in the following weight proportions:

[0045] Triethanolamine: 2% (10 grams), benzene hydrochloride: 3% (15 grams), industrial alcohol: 90% (450 grams), rosin: 5% (25 grams), totaling 100% (500 grams).

[0046] Specifically, the high-lead solder paste also contains other trace metal elements, the total content of which does not exceed 0.1%, and the trace metal elements are used to improve specific properties of the solder paste.

[0047] Specifically, the lead-free solder further includes Ga element or Ge element, and the content of each element is respectively as follows in weight percentage: Ga: 0.001-0.1%, Ge: 0.001-0.1%.

[0048] Specifically, the no-clean flux includes the following raw materials in the following weight ratios:

[0049] Succinic acid: 1.5%, adipic acid: 1.0%, dibromobutenedioic acid: 0.2%, dibromobutenedioic acid: 0.68%, OP-10: 0.35%, FSN-100: 0.05%, ethanol balance.

[0050] Specifically, when preparing the no-clean flux, pour an appropriate amount of ethanol into a glass container, then add various ingredients in sequence, and then stir with an insulating rod until uniform.

[0051] Specifically, the rosin-based flux includes the following raw materials in the following weight proportions:

[0052] Rosin: 25%, Alcohol: 75%.

[0053] It should be noted that the concentration of alcohol in the rosin-type flux is 99.5%. When preparing the rosin-type flux, rosin is dissolved in alcohol to form a uniform solution.

[0054] Example 2:

[0055] A preparation process of a high-temperature resistant active solder material for IGBT, comprising the following steps:

[0056] S1. Raw material preparation: Prepare high-lead solder paste raw materials, lead-free solder raw materials, and flux raw materials according to the given weight ratios. Ensure that the purity and quality of the high-lead solder paste raw materials meet the requirements to avoid impurities affecting the performance of the soldering materials. Lead-free solder raw materials must undergo strict screening and testing to ensure that their composition is accurate and free of harmful impurities. Ensure that the industrial alcohol is of high purity and that the rosin is ground into a fine powder to improve the performance of the flux.

[0057] S2. Preparation of high-lead solder paste: Weighed Sn, Pb, and YN are placed in a melting furnace and smelted at a temperature of 300-350°C to fully melt and mix the raw materials. After smelting, the molten alloy liquid is poured into a mold for cooling. After cooling to room temperature, the formed high-lead solder paste is removed and then cut and ground as needed to achieve the desired shape and size.

[0058] S3. Preparation of lead-free solder: Weighed Sn, Ag, and Cu are placed in a smelting device and smelted at a temperature of 220-250°C. After smelting, the smelted alloy liquid is poured into a mold for cooling. After cooling to room temperature, the formed lead-free solder is removed and subsequently processed as needed to obtain the desired solder shape.

[0059] S4. Preparation of solder flux: Pour the weighed triethanolamine, benzene hydrochloride, and rosin powder into a glass container that is easy to stir; then pour industrial alcohol into the container and immediately stir the liquid with an insulating rod until the liquid is very uniform when viewed along the glass container under sunlight; finally, pour hot water into a porcelain basin and place the glass container in the basin. Continue to heat the water in the basin for 30 minutes, then remove the solution and use it;

[0060] S5. Mixing and blending: Mix the prepared high-lead solder paste, lead-free solder and flux in a certain proportion. During the mixing process, ensure that all ingredients are fully mixed to avoid local unevenness. Use a stirring device to stir. The stirring time and speed should be adjusted according to the characteristics of the mixture and the mixing requirements.

[0061] S6. Quality testing: Conduct various performance tests on the prepared high-temperature resistant active soldering materials for IGBT, including melting point, wettability, mechanical strength and high-temperature resistance; adjust and optimize the preparation process to ensure that the quality of the soldering materials meets the requirements;

[0062] S7. Packaging and storage: Pack the qualified welding materials and mark the product name, specifications, model, production date and shelf life on the packaging; store the packaged welding materials in a dry, cool and ventilated environment.

[0063] Specifically, during the smelting process in S2, continuous stirring is required to ensure that the components are evenly distributed to avoid component segregation. During the smelting process in S3, continuous stirring is required to ensure that silver and copper are evenly dispersed in the tin matrix to form a uniform alloy. The solder forms in S3 include welding wire and welding sheet.

[0064] Specifically, the melting point test in S6 measures the melting point of the welding material using a differential scanning calorimeter to ensure that it meets the requirements of IGBT welding; the wettability test in S6 measures the wetting angle of the welding material on the substrate surface using a wetting angle meter. The smaller the wetting angle, the better the wettability, which is conducive to improving the welding quality; the mechanical strength test in S6 uses a tensile testing machine to perform a tensile test on the welded joint to detect its mechanical performance index of tensile strength; the high temperature resistance test in S6 places the welding material or welded joint in a high temperature environment, observes its performance changes at high temperature, observes whether it softens or deforms, and evaluates its high temperature resistance.

[0065] The beneficial effects of this embodiment are:

[0066] The high-temperature resistant active soldering material for IGBT and its preparation process are prepared by a reasonable ratio of high-lead solder paste, lead-free solder and specific flux selection. The high-temperature resistant active soldering material has excellent high-temperature resistance. Compared with traditional soldering materials, the soldering material is less likely to soften or deform at high temperatures of 180°C or even 200°C, effectively avoiding the performance degradation or failure of the IGBT module caused by failure of the soldering material, greatly improving the operating reliability of the IGBT module in a high-temperature environment, extending its service life, and reducing losses such as equipment downtime and maintenance costs caused by module failure, thereby achieving the advantages of high-temperature resistance, good activity and high welding quality.

[0067] The high-temperature resistant active welding material for IGBT and its preparation process, by adopting the above-mentioned preparation process to prepare the high-temperature resistant active welding material, can effectively improve the overall stability of the welding material, can effectively improve the overall environmental performance of the welding material, can effectively improve the overall flexibility of the welding material, and achieve the advantages of good stability and good environmental protection effect.

[0068] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A high-temperature resistant active solder material for IGBT, characterized by: Including high-lead solder paste, lead-free solder and flux; The high-lead solder paste comprises the following raw materials in the following weight proportions: Sn: 95%-97%, Pb: 2%-4%, YN: 0%-1%; The lead-free solder comprises the following raw materials in the following weight proportions: Sn: 95.5%-96.5%, Ag: 3.0%-3.8%, Cu: 0.5%-0.7%; The soldering flux is any one of 891 soldering flux, no-clean soldering flux or rosin soldering flux; The 891 soldering flux comprises the following raw materials in the following weight proportions: Triethanolamine: 2%, benzene hydrochloride: 3%, industrial alcohol: 90%, rosin: 5%.

2. The high temperature resistant active solder material for IGBT according to claim 1, characterized in that: The high-lead solder paste further contains other trace metal elements, the total content of which does not exceed 0.1%. The trace metal elements are used to improve specific properties of the solder paste.

3. The high temperature resistant active solder material for IGBT according to claim 1, characterized in that: The lead-free solder further comprises Ga element or Ge element, and the content of each element is respectively as follows in weight percentage: Ga: 0.001-0.1%, Ge: 0.001-0.1%.

4. The high temperature resistant active solder material for IGBT according to claim 1, characterized in that: The no-clean soldering flux comprises the following raw materials in the following weight proportions: Succinic acid: 1.5%, adipic acid: 1.0%, dibromobutenedioic acid: 0.2%, dibromobutenedioic acid: 0.68%, OP-10: 0.35%, FSN-100: 0.05%, ethanol balance.

5. The high temperature resistant active solder material for IGBT according to claim 4, characterized in that: When preparing the no-clean soldering flux, pour an appropriate amount of ethanol into a glass container, then add various ingredients in sequence, and stir with an insulating rod until uniform.

6. The high temperature resistant active solder material for IGBT according to claim 1, characterized in that: The rosin-based soldering flux comprises the following raw materials in the following weight proportions: Rosin: 25%, Alcohol: 75%.

7. The high temperature resistant active solder material for IGBT according to claim 6, characterized in that: The concentration of alcohol in the rosin-type soldering flux is 99.5%. When preparing the rosin-type soldering flux, rosin is dissolved in alcohol to form a uniform solution.

8. A process for preparing a high-temperature resistant active solder material for IGBT, using the high-temperature resistant active solder material for IGBT according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1. Raw material preparation: Prepare high-lead solder paste raw materials, lead-free solder raw materials, and flux raw materials according to the given weight ratios. Ensure that the purity and quality of the high-lead solder paste raw materials meet the requirements to avoid impurities affecting the performance of the soldering materials. Lead-free solder raw materials must undergo strict screening and testing to ensure that their composition is accurate and free of harmful impurities. Ensure that the industrial alcohol is of high purity and that the rosin is ground into a fine powder to improve the performance of the flux. S2. Preparation of high-lead solder paste: Weighed Sn, Pb, and YN are placed in a melting furnace and smelted at a temperature of 300-350°C to fully melt and mix the raw materials. After smelting, the molten alloy liquid is poured into a mold for cooling. After cooling to room temperature, the formed high-lead solder paste is removed and then cut and ground as needed to achieve the desired shape and size. S3. Preparation of lead-free solder: Weighed Sn, Ag, and Cu are placed in a smelting device and smelted at a temperature of 220-250°C. After smelting, the smelted alloy liquid is poured into a mold for cooling. After cooling to room temperature, the formed lead-free solder is removed and subsequently processed as needed to obtain the desired solder shape. S4. Preparation of solder flux: Pour the weighed triethanolamine, benzene hydrochloride, and rosin powder into a glass container that is easy to stir; then pour industrial alcohol into the container and immediately stir the liquid with an insulating rod until the liquid is very uniform when viewed along the glass container under sunlight; finally, pour hot water into a porcelain basin and place the glass container in the basin. Continue to heat the water in the basin for 30 minutes, then remove the solution and use it; S5. Mixing and blending: Mix the prepared high-lead solder paste, lead-free solder and flux in a certain proportion. During the mixing process, ensure that all ingredients are fully mixed to avoid local unevenness. Use a stirring device to stir. The stirring time and speed should be adjusted according to the characteristics of the mixture and the mixing requirements. S6. Quality testing: Conduct various performance tests on the prepared high-temperature resistant active soldering materials for IGBT, including melting point, wettability, mechanical strength and high-temperature resistance; adjust and optimize the preparation process to ensure that the quality of the soldering materials meets the requirements; S7. Packaging and storage: Pack the qualified welding materials and mark the product name, specifications, model, production date and shelf life on the packaging; store the packaged welding materials in a dry, cool and ventilated environment.

9. The process for preparing a high-temperature resistant active solder material for IGBT according to claim 8, characterized in that: During the smelting process in S2, continuous stirring is required to ensure that the components are evenly distributed to avoid component segregation. During the smelting process in S3, continuous stirring is required to ensure that silver and copper are evenly dispersed in the tin matrix to form a uniform alloy. The solder in S3 includes solder wire and solder sheet.

10. The process for preparing a high temperature resistant active solder material for IGBT according to claim 8, characterized in that: The melting point test in S6 measures the melting point of the welding material by using a differential scanning calorimeter to ensure that it meets the requirements of IGBT welding; the wettability test in S6 measures the wetting angle of the welding material on the surface of the substrate by using a wetting angle measuring instrument. The smaller the wetting angle, the better the wettability, which is conducive to improving the welding quality; the mechanical strength test in S6 uses a tensile testing machine to perform a tensile test on the welding joint to detect its mechanical performance index of tensile strength; the high temperature resistance test in S6 places the welding material or welding joint in a high temperature environment, observes its performance changes at high temperature, observes whether it softens or deforms, and evaluates its high temperature resistance.