CN116652319A - Tin dioxide nanoparticle reinforced lead-free composite paste and welding spot formed by same - Google Patents
Tin dioxide nanoparticle reinforced lead-free composite paste and welding spot formed by same Download PDFInfo
- Publication number
- CN116652319A CN116652319A CN202310677631.6A CN202310677631A CN116652319A CN 116652319 A CN116652319 A CN 116652319A CN 202310677631 A CN202310677631 A CN 202310677631A CN 116652319 A CN116652319 A CN 116652319A
- Authority
- CN
- China
- Prior art keywords
- tin
- silver
- free
- lead
- tin dioxide
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- XOLBLPGZBRYERU-UHFFFAOYSA-N tin dioxide Chemical compound O=[Sn]=O XOLBLPGZBRYERU-UHFFFAOYSA-N 0.000 title claims abstract description 98
- 239000002105 nanoparticle Substances 0.000 title claims abstract description 48
- 239000002131 composite material Substances 0.000 title claims abstract description 32
- 238000003466 welding Methods 0.000 title description 19
- 229910000679 solder Inorganic materials 0.000 claims abstract description 71
- 238000005476 soldering Methods 0.000 claims abstract description 23
- 239000011135 tin Substances 0.000 claims abstract description 14
- 229910052718 tin Inorganic materials 0.000 claims abstract description 14
- ATJFFYVFTNAWJD-UHFFFAOYSA-N Tin Chemical compound [Sn] ATJFFYVFTNAWJD-UHFFFAOYSA-N 0.000 claims abstract description 13
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims abstract description 8
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 claims abstract description 8
- 229910052802 copper Inorganic materials 0.000 claims abstract description 8
- 239000010949 copper Substances 0.000 claims abstract description 8
- 229910052709 silver Inorganic materials 0.000 claims abstract description 8
- 239000004332 silver Substances 0.000 claims abstract description 8
- 239000000758 substrate Substances 0.000 claims description 3
- 238000007650 screen-printing Methods 0.000 claims description 2
- 238000010907 mechanical stirring Methods 0.000 claims 1
- PQIJHIWFHSVPMH-UHFFFAOYSA-N [Cu].[Ag].[Sn] Chemical compound [Cu].[Ag].[Sn] PQIJHIWFHSVPMH-UHFFFAOYSA-N 0.000 abstract description 34
- 229910000969 tin-silver-copper Inorganic materials 0.000 abstract description 34
- 230000035939 shock Effects 0.000 abstract description 10
- 229910006640 β-Sn Inorganic materials 0.000 abstract description 6
- 229910006632 β—Sn Inorganic materials 0.000 abstract description 6
- 238000000034 method Methods 0.000 abstract description 5
- 239000013078 crystal Substances 0.000 abstract description 2
- 238000010008 shearing Methods 0.000 abstract 1
- 239000011159 matrix material Substances 0.000 description 7
- 238000001000 micrograph Methods 0.000 description 5
- 150000001875 compounds Chemical class 0.000 description 4
- 229910000765 intermetallic Inorganic materials 0.000 description 4
- 239000000654 additive Substances 0.000 description 3
- 230000000996 additive effect Effects 0.000 description 3
- 238000005219 brazing Methods 0.000 description 3
- 239000000945 filler Substances 0.000 description 3
- LQBJWKCYZGMFEV-UHFFFAOYSA-N lead tin Chemical compound [Sn].[Pb] LQBJWKCYZGMFEV-UHFFFAOYSA-N 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 238000005275 alloying Methods 0.000 description 2
- 238000004100 electronic packaging Methods 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 229910017482 Cu 6 Sn 5 Inorganic materials 0.000 description 1
- 208000012868 Overgrowth Diseases 0.000 description 1
- 229910006404 SnO 2 Inorganic materials 0.000 description 1
- 230000032683 aging Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000000052 comparative effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 230000005496 eutectics Effects 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000007726 management method Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- QSHDDOUJBYECFT-UHFFFAOYSA-N mercury Chemical compound [Hg] QSHDDOUJBYECFT-UHFFFAOYSA-N 0.000 description 1
- 229910052753 mercury Inorganic materials 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 238000011056 performance test Methods 0.000 description 1
- 238000011954 pollution control method Methods 0.000 description 1
- 238000007670 refining Methods 0.000 description 1
- 230000002787 reinforcement Effects 0.000 description 1
- 230000003014 reinforcing effect Effects 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K3/00—Tools, devices, or special appurtenances for soldering, e.g. brazing, or unsoldering, not specially adapted for particular methods
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K3/00—Tools, devices, or special appurtenances for soldering, e.g. brazing, or unsoldering, not specially adapted for particular methods
- B23K3/08—Auxiliary devices therefor
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Electric Connection Of Electric Components To Printed Circuits (AREA)
Abstract
The tin dioxide nanoparticle reinforced lead-free composite paste is prepared by mixing tin dioxide nanoparticles with tin-silver-copper lead-free soldering paste, wherein the mass percentage of tin, silver and copper in the tin-silver-copper lead-free soldering paste is 96.5:3.0:0.5, and the addition amount of the tin dioxide nanoparticles is 0.3-1.2 wt%. According to the invention, the microstructure of the tin-silver-copper lead-free solder can be refined by adding a proper amount of tin dioxide nano particles, the size of beta-Sn crystal grains in the solder is reduced, and the growth of interfacial IMC in the process of reflow soldering and thermal shock at-196 ℃ to +150 ℃ is inhibited, so that the shearing strength is respectively improved by 15% and 20% compared with that of a tin-silver-copper lead-free solder, and the reliability of the solder under an extreme temperature environment can be improved by adding a proper amount of tin dioxide nano particles in the tin-silver-copper lead-free solder.
Description
Technical Field
The invention relates to the technical field of lead-free solder, in particular to tin dioxide nanoparticle reinforced lead-free composite paste capable of improving the extreme temperature reliability of a welding spot and the welding spot formed by the tin dioxide nanoparticle reinforced lead-free composite paste.
Background
Tin-lead solder has been the mainstream solder in electronic industry applications because of its good performance and low cost. Lead and its compounds present a significant hazard to both the ecological environment and human health. The pollution control and management method of electronic information products issued in 2006 in China clearly indicates that harmful substances such as lead, mercury and the like are forbidden to be used in the electronic information products. The replacement of tin-lead solder with lead-free solder has become a necessary trend in the development of electronic packaging solder, and a great amount of funds are put into various countries to develop green environment-friendly lead-free solder so as to preempt the preemption in vigorous competition. Among the lead-free solders of many systems, snAgCu-based lead-free solders are considered to be the lead-free solders most likely to replace the conventional tin-lead solders due to their excellent combination properties, and have been widely used in the manufacturing industry. However, compared with the eutectic solder of tin and lead, the lead-free solder of SnAgCu has a plurality of non-negligible problems, such as the easy formation of larger brittle intermetallic compounds (Ag 3 Sn and Cu 6 Sn 5 ) The mechanical property of the solder is reduced; overgrowth of interfacial intermetallic compounds during welding or high temperature service can lead to reduced mechanical properties of the weld and even to failure of the weld. In order to improve the performance of the SnAgCu lead-free solder and improve the service reliability, two methods are generally adopted: (1) Micro alloying of the solder, wherein trace alloying elements are mainly added into the lead-free solder, so that a certain performance or comprehensive performance of the solder is improved; (2) Preparing composite brazing filler metal, adding particles with micrometer scale or nanometer scale into the brazing filler metal, and improving the performance of the brazing filler metal through particle reinforcement.
The spacecraft electronic product can experience an extreme temperature environment containing high temperature, extremely low temperature and alternating high and low temperature in the deep space detection process, for example, the daytime temperature of the lunar surface is about +150 ℃ at most, the night temperature is as low as-180 ℃, and the lunar surface temperature can be changed drastically during the day-night alternation. Interconnect pads play a role in mechanical support and electrical connection in electronic packaging systems, and the reliability of the pads is critical to the proper operation of the electronic product. The extreme temperature environment in deep space exploration presents a significant challenge to the reliability of interconnect pads. Studies have shown that in extreme temperature environments, rapid growth of interfacial intermetallic compounds (IMCs) is one of the important causes of lead-free solder joint failure. The lead-free composite solder developed at present is not subjected to reliability evaluation under the extreme temperature condition, namely, a conclusion on whether the extreme temperature reliability of the interconnection welding spots can be improved is not obtained. Therefore, there is a need to develop a lead-free composite solder that can improve the extreme temperature reliability of the interconnect pads.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides a lead-free composite solder capable of improving the extreme temperature reliability of an interconnection welding spot, which is finished by adding a certain amount of tin dioxide nano particles.
In order to achieve the above purpose, the present invention provides the following technical solutions:
the tin dioxide nanoparticle reinforced lead-free composite paste is prepared by mixing tin dioxide nanoparticles with tin-silver-copper lead-free soldering paste, wherein the mass percentage of tin, silver and copper in the tin-silver-copper lead-free soldering paste is 96.5:3.0:0.5, and the addition amount of the tin dioxide nanoparticles is 0.3-1.2 wt%.
Further, the diameter of the tin dioxide nano-particles is 30-50 nm.
Further, the invention provides a welding spot formed by the tin dioxide nano particle reinforced lead-free composite paste, which is prepared by adding the tin dioxide nano particles into tin, silver and copper lead-free solder paste, mechanically stirring uniformly, then screen printing on a substrate bonding pad, and carrying out reflow soldering for 90s, wherein the diameter of the bonding pad is 250 mu m.
Compared with the prior art, the invention has the beneficial effects that:
1. the addition of the tin dioxide nano particles can refine the microstructure of the tin-silver-copper lead-free solder, reduce the size of beta-Sn crystal grains in the solder, and inhibit the growth of interface IMC in the process of reflow soldering and thermal shock at-196 ℃ to +150 ℃;
2. after reflow soldering for 90 seconds, the shear strength of the composite solder welding spot added with the tin dioxide nano particles with the mass fraction of 0.8% is improved by 15% compared with that of a tin-silver-copper leadless welding spot;
3. after thermal shock 300 circulation at the temperature of 196 ℃ below zero to 150 ℃, the shear strength of the composite solder welding spot added with the tin dioxide nano particles with the mass fraction of 0.8% is improved by 20% compared with that of a tin-silver-copper lead-free welding spot;
the above description shows that the addition of a proper amount of tin dioxide nanoparticles to tin-silver-copper lead-free solder paste can improve the reliability of the solder joint in an extreme temperature environment.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the description of the embodiments or the prior art will be briefly described, and it is obvious that the drawings in the description below are some embodiments of the present invention, and other drawings can be obtained according to the drawings without inventive effort for a person skilled in the art.
Fig. 1 is a scanning electron microscope image of a tin-silver-copper lead-free solder paste without tin dioxide nanoparticles added after 90s reflow.
Fig. 2 is a scanning electron microscope image of the compound solder paste added with 0.3% mass fraction of tin dioxide nanoparticles in example 1 after reflow for 90 s.
Fig. 3 is a scanning electron microscope image of the compound solder paste added with 0.8% mass fraction of tin dioxide nanoparticles in example 2 after reflow for 90 s.
Fig. 4 is a scanning electron microscope image of the compound solder paste added with 1.2% mass fraction of tin dioxide nanoparticles in example 3 after reflow for 90 s.
Fig. 5 is a graph comparing the IMC thickness of the solder joint interface prepared from tin dioxide nanoparticle reinforced tin-silver-copper composite solder paste with different additive amounts.
FIG. 6 is a graph showing the comparison of interfacial IMC thicknesses after thermal shocks of 100, 200 and 300 cycles at-196 ℃ to +150 ℃ for solder joints made from tin dioxide nanoparticle-reinforced tin-silver-copper composite solder pastes with different additive amounts.
Fig. 7 is a graph showing the shear strength comparison of solder joints made from tin dioxide nanoparticle reinforced tin-silver-copper composite solder paste with different additive amounts after reflow soldering for 90s and after undergoing thermal shock 100, 200 and 300 cycles at-196 ℃ to +150 ℃.
Detailed Description
The following description of the embodiments of the present invention will be made apparent and fully in view of the accompanying drawings, in which some, but not all embodiments of the invention are shown. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
In addition, the technical features of the different embodiments of the present invention described below may be combined with each other as long as they do not collide with each other.
Example 1:
tin dioxide nano particles with the mass percentage of 0.3% are added into the tin-silver-copper lead-free soldering paste, the mass percentage of tin, silver and copper in the tin-silver-copper lead-free soldering paste is 96.5:3.0:0.5, the diameter of the tin dioxide nano particles is 30-50 nm, and the tin dioxide nano particles are mechanically stirred for more than 1 hour, so that the tin dioxide nano particles are uniformly dispersed in the tin-silver-copper lead-free soldering paste, and 0.3% SnO can be prepared 2 And (3) reinforcing the tin-silver-copper lead-free composite soldering paste.
The scanning electron microscope images of the tin-silver-copper lead-free solder paste and the composite solder paste obtained in the embodiment after reflow for 90s are shown in fig. 1 and fig. 2 respectively. The gray matrix in fig. 1 is tin-rich phase beta-Sn with an average grain size of 8.8 μm. The gray matrix in fig. 2 is tin-rich phase beta-Sn with an average grain size of 7.1 μm. It can be seen that the solder matrix structure of the composite solder paste to which the tin dioxide nanoparticles were added in an amount of 0.3% by mass was refined compared to the tin-silver-copper lead-free solder paste.
Example 2:
as in example 1, the addition amount of tin dioxide nanoparticles was changed to 0.8%, and 0.8% SnO was obtained 2 The enhanced tin-silver-copper lead-free composite solder paste is shown in fig. 3, and the gray matrix in fig. 3 is tin-rich phase beta-Sn, and the average grain size is 4.5 mu m. It can be seen that compared with the addition of 0.3% SnO 2 0.8% SnO was added to the composite solder paste of (example 1) 2 Is organized into a solder matrix of a composite solder paste (this embodiment)The refining is achieved in one step.
Example 3:
as in example 1, the addition amount of tin dioxide nanoparticles was changed to 1.2%, and 1.2% SnO was obtained 2 The enhanced tin-silver-copper lead-free composite solder paste is shown in fig. 4, wherein the gray matrix in fig. 4 is tin-rich phase beta-Sn, and the average grain size is 5.9 mu m. It can be seen that the solder matrix structure of the composite solder paste (this example) to which 1.2 mass% of tin dioxide nanoparticles were added was refined compared to the tin-silver-copper lead-free solder paste.
Example 4:
the tin dioxide nanoparticle reinforced tin-silver-copper composite soldering paste obtained in examples 1 to 3 and the tin-silver-copper lead-free soldering paste are screen printed on a substrate bonding pad, the bonding pad diameter is 250 μm, and a Ball Grid Array (BGA) bonding pad is prepared after reflow soldering for 90 seconds, and a bonding pad interface IMC thickness comparison chart is shown in FIG. 5. The result proves that the interface IMC thickness of the solder joint after reflow soldering can be remarkably reduced by adding 0.8% mass fraction of tin dioxide nano particles into the tin-silver-copper lead-free solder paste.
Example 5:
the thermal shock test was performed on the solder joint obtained in example 4, and the solder joint was placed in an aging oven at 150℃and liquid nitrogen at-196℃to and fro, and was kept at the highest temperature (+150℃) and the lowest temperature (-196 ℃) for 30 minutes, respectively. A group of samples were taken every 100 cycles, and the thickness of the weld interface IMC was observed with a scanning electron microscope, and a graph of the weld interface IMC thickness comparison after thermal shock is shown in fig. 6. The results prove that after thermal shock is carried out at the temperature of minus 196 ℃ to plus 150 ℃ for 100, 200 and 300 cycles, the interface IMC thickness of the composite welding spot is always lower than that of a tin-silver-copper lead-free welding spot, and the tin dioxide nano particles with the mass fraction of 0.3 to 1.2 percent are added into the tin-silver-copper lead-free soldering paste, so that the growth of the interface IMC in the thermal shock process can be inhibited.
Example 6:
BGA solder joint shear performance tests were conducted on the tin dioxide nanoparticle reinforced tin-silver-copper composite solder joints and the tin-silver-copper lead-free solder joints prepared in examples 4 and 5, the shear heights and shear rates were set to 30 μm and 300 μm/s, respectively, and the comparative graphs of solder joint shear strengths after reflow soldering and thermal shock are shown in FIG. 7. The result proves that after reflow soldering for 90 seconds, the shear strength of the composite solder welding spot added with the tin dioxide nano particles with the mass fraction of 0.8% is improved by 15% compared with that of a tin-silver-copper lead-free welding spot. After 300 cycles, the shear strength of the composite solder welding spot added with 0.8% mass fraction of tin dioxide nano particles is improved by 20% compared with that of a tin-silver-copper lead-free welding spot, which indicates that the reliability of the welding spot in an extreme temperature environment can be improved by adding a proper amount of tin dioxide nano particles into the tin-silver-copper lead-free solder paste.
Although embodiments of the present invention have been disclosed above, it is not limited to the details and embodiments shown and described, it is well suited to various fields of use for which the invention would be readily apparent to those skilled in the art, and accordingly, the invention is not limited to the specific details and illustrations shown and described herein, without departing from the general concepts defined in the claims and their equivalents.
Claims (3)
1. The tin dioxide nanoparticle reinforced lead-free composite paste is characterized by being prepared by mixing tin dioxide nanoparticles with tin, silver and copper lead-free soldering paste, wherein the mass percentage of tin, silver and copper in the tin, silver and copper lead-free soldering paste is 96.5:3.0:0.5, and the addition amount of the tin dioxide nanoparticles is 0.3-1.2 wt%.
2. The tin dioxide nanoparticle reinforced lead-free composite paste of claim 1, wherein the diameter of the tin dioxide nanoparticle is between 30 and 50nm.
3. The solder joint formed by the tin dioxide nanoparticle reinforced lead-free composite paste according to claim 1 or 2, wherein the tin dioxide nanoparticle is added into tin, silver and copper lead-free solder paste, and the solder joint is prepared after mechanical stirring is carried out uniformly, then screen printing is carried out on a substrate bonding pad, the bonding pad diameter is 250 mu m, and reflow soldering is carried out for 90 s.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310677631.6A CN116652319A (en) | 2023-06-08 | 2023-06-08 | Tin dioxide nanoparticle reinforced lead-free composite paste and welding spot formed by same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310677631.6A CN116652319A (en) | 2023-06-08 | 2023-06-08 | Tin dioxide nanoparticle reinforced lead-free composite paste and welding spot formed by same |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN116652319A true CN116652319A (en) | 2023-08-29 |
Family
ID=87718752
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202310677631.6A Pending CN116652319A (en) | 2023-06-08 | 2023-06-08 | Tin dioxide nanoparticle reinforced lead-free composite paste and welding spot formed by same |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN116652319A (en) |
-
2023
- 2023-06-08 CN CN202310677631.6A patent/CN116652319A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR102133347B1 (en) | Solder alloy, solder ball, solder preform, solder paste and solder joint | |
| TWI655052B (en) | Lead-free, flawless solder alloy, its use, including solder joints, and methods of forming solder joints | |
| DE60019651T2 (en) | LEAD-FREE SOFT PLATE | |
| CN1390672A (en) | Leadfree SnZn-base alloy solder containing rare-earth elements | |
| HUE033232T2 (en) | Lead-free solder alloy | |
| KR20160124724A (en) | Method for producing solder powder and solder paste using the powder | |
| Bang et al. | Intermetallic compound growth between Sn-Cu-Cr lead-free solder and Cu substrate | |
| CN101374630A (en) | Solder alloy, solder ball and solder joint using same | |
| CN108927609B (en) | Preparation method of composite lead-free solder paste | |
| CN113725185B (en) | Sn-based solder capable of realizing vertical stacking of chips and bonding method thereof | |
| CN101579790B (en) | Sn-Ag-Cu lead-free solder containing Nd, Li, As and In | |
| CN111230355A (en) | Lead-free solder alloy for replacing Sn-Pb alloy, SAC305, Sn-Cu and Sn100C | |
| EP3707285B1 (en) | Low-silver tin based alternative solder alloy to standard sac alloys for high reliability applications | |
| CN116652319A (en) | Tin dioxide nanoparticle reinforced lead-free composite paste and welding spot formed by same | |
| Huang et al. | Microstructures and shear properties of mixed assembly BGA structure SnAgCu/SnBi (Ag)/Cu joints in board-level packaging | |
| CN113385853A (en) | Low-silver high-reliability lead-free soft solder and preparation method and application thereof | |
| EP3707286B1 (en) | High reliability lead-free solder alloy for electronic applications in extreme environments | |
| Bashir et al. | Effect of Zn nanoparticle-doped flux on mechanical properties of SAC305 solder joint after electromigration | |
| CN1358606A (en) | Metal granule reinforced tin-lead base composite soldering flux and making method | |
| JP5167068B2 (en) | Electronic member having solder balls and solder bumps | |
| CN106271183A (en) | MEMS three-dimension packaging interconnection material | |
| Wada et al. | Superior thermal cycling reliability of Pb-free solder alloy by addition of indium and bismuth for harsh environments | |
| Law | Reliability and interfacial reaction of lead-free solder alloys doped with rare earth elements | |
| CN116423096A (en) | Novel indium-based particle composite solder component and preparation method of packaging welding spot | |
| CN116586815A (en) | SnAgCu series high-temperature stable solder alloy and application thereof |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |