CN111347193A - High-reliability solder paste and preparation method thereof - Google Patents
High-reliability solder paste and preparation method thereof Download PDFInfo
- Publication number
- CN111347193A CN111347193A CN202010302412.6A CN202010302412A CN111347193A CN 111347193 A CN111347193 A CN 111347193A CN 202010302412 A CN202010302412 A CN 202010302412A CN 111347193 A CN111347193 A CN 111347193A
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- Prior art keywords
- stirring
- solder paste
- paste
- flux
- tin
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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
- B23K35/00—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting
- B23K35/22—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting characterised by the composition or nature of the material
- B23K35/36—Selection of non-metallic compositions, e.g. coatings, fluxes; Selection of soldering or welding materials, conjoint with selection of non-metallic compositions, both selections being of interest
- B23K35/362—Selection of compositions of fluxes
-
- 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
- B23K35/00—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting
- B23K35/02—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting characterised by mechanical features, e.g. shape
- B23K35/0222—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting characterised by mechanical features, e.g. shape for use in soldering, brazing
- B23K35/0244—Powders, particles or spheres; Preforms made therefrom
- B23K35/025—Pastes, creams, slurries
-
- 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
- B23K35/00—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting
- B23K35/22—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting characterised by the composition or nature of the material
- B23K35/24—Selection of soldering or welding materials proper
- B23K35/26—Selection of soldering or welding materials proper with the principal constituent melting at less than 400 degrees C
- B23K35/262—Sn as the principal constituent
-
- 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
- B23K35/00—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting
- B23K35/22—Rods, electrodes, materials, or media, for use in soldering, welding, or cutting characterised by the composition or nature of the material
- B23K35/36—Selection of non-metallic compositions, e.g. coatings, fluxes; Selection of soldering or welding materials, conjoint with selection of non-metallic compositions, both selections being of interest
- B23K35/3612—Selection of non-metallic compositions, e.g. coatings, fluxes; Selection of soldering or welding materials, conjoint with selection of non-metallic compositions, both selections being of interest with organic compounds as principal constituents
- B23K35/3613—Polymers, e.g. resins
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Electric Connection Of Electric Components To Printed Circuits (AREA)
Abstract
The invention relates to the technical field of tin solder, and discloses high-reliability tin paste which comprises the following components in percentage by mass: 10-12% of soldering flux and 88-90% of SnAgCuCe series soldering tin powder; also discloses a preparation method thereof: firstly, preparing a soldering paste; and secondly, preparing the soldering paste. The invention can avoid welding spot cracking after 2000 times of cold and hot circulation and has strong practicability.
Description
Technical Field
The invention relates to the technical field of tin solder, in particular to high-reliability tin paste.
Background
Modern electronic packaging devices are composed of a wide variety of materials whose coefficient of thermodynamic expansion varies over a range. Electronic devices generate heat during use, and due to the inconsistency of the physical constants of the materials, thermal stress and strain are generated inside the devices. Therefore, the primary issue to consider in selecting materials is whether the thermodynamic constants match. However, in practice it is not possible to find two materials that match exactly, so thermal stresses cannot be avoided in the assembled device and interconnect material. This requires that the solder alloy that is the preferred material for the interconnects be strong enough to withstand the thermal stresses required.
It is worth noting that in the using process, the actual temperature is very close to the melting point of the solder, which requires that the welding material has better creep resistance, the most widely used is Sn-Ag-Cu solder internationally, but the Sn-Ag-Cu solder has the problem of thick IMC, compared with Sn-Pb solder, the lead-free solder still has the defects of poor wettability, high welding temperature, high metal dissolution speed and the like, and the interface is easy to grow up quickly and form welding holes on the welding interface, so that the reliability of welding spots is reduced. Particularly, for the electronic products with high reliability requirements at present, for example, after more than 2000 times of cold-hot cycles (40 ℃ below zero to 120 ℃), the Sn-Ag-Cu solder widely used at present has the defects of cracking and the like, and the development of a tin paste capable of meeting the high reliability requirements of the electronic products is urgently needed.
Disclosure of Invention
The invention aims to provide a high-reliability solder paste and a preparation method thereof, wherein a welding spot can not crack after 2000 times of cold and hot circulation, so as to solve the problems in the background technology.
In order to achieve the purpose, the invention provides the following technical scheme:
a high-reliability solder paste comprises the following components in percentage by mass: 10-12% of soldering flux and 88-90% of SnAgCuCe series soldering tin powder.
As a further scheme of the invention: the soldering flux comprises the following components in percentage by mass: 40-50% of rosin, 5-11% of an active agent, 20-40% of a solvent and 4-7% of a thixotropic agent.
As a further scheme of the invention: the rosin is one or more of Clearon P-105 rosin and Foral AX-E, KE-100 rosin.
As a further scheme of the invention: the active agent is one or more of dimer acid, pentaerythritol palmitate, diethylamine hydrobromide and FS-3100.
As a further scheme of the invention: the solvent is one or more of diethylene glycol monoethyl ether, diethylene glycol monohexyl ether and tetrahydrofurfuryl alcohol.
As a further scheme of the invention: the thixotropic agent is one or more of methylbenzotriazole, hydrogenated castor oil and stearic acid amide SLPACKS ZHH.
As a further scheme of the invention: the particle size of the solder paste is 20-38 μm.
As a still further scheme of the invention: the tin powder comprises the following components in percentage by weight: tin: 96.2-99%, silver: 0.3-3.0%, copper: 0.5-0.7% of cerium and 0.01-0.05% of cerium.
A preparation method of high-reliability solder paste comprises the following steps:
first, preparation of flux paste
(1) Weighing the following components:
weighing the solvent, the rosin and the activator thixotropic agent in turn by using an electronic balance according to the designed proportion for later use;
(2) heating for dissolving:
adding the weighed solvent and rosin in the step (1) into a stainless steel reaction kettle, adjusting the heating power of the reaction kettle to heat the reaction kettle to 110 ℃ at a heating rate of about 5 ℃/s, keeping the temperature, stirring at a low speed of 50r/min in the whole process until all the components are completely dissolved, cooling the system to 90 ℃ until the system is in a clear and transparent state, adding an active agent, stopping heating and stirring after the components are completely dissolved, and performing the next step of operation;
(3) emulsification and dispersion:
when the solution in the step (2) is cooled to 80 ℃ along with the reaction kettle, adding a thixotropic agent, carrying out high-speed emulsification, controlling the emulsification rotating speed within 6000r/min, carrying out canning and standing after the emulsification is finished, cooling to room temperature, and sealing and standing for 100 hours;
(4) grinding and refining:
grinding and refining the substances which are completely cooled in the step (3) by using a stainless steel three-roller grinder, and repeatedly grinding the soldering flux for the solder paste twice;
second step, preparation of solder paste
(1) Flux paste component weighing
Precisely weighing 11.5% of flux paste and 88.5% of tin, silver, copper, cerium and tin powder;
(2) stirring soldering paste
Adding the flux paste into a stirring kettle of a solder paste stirrer, and stirring for 3 minutes at a rotating speed of 20 revolutions per minute;
(3) adding tin powder
The tin paste stirrer maintains the rotating speed of 20 revolutions per minute, and 3Kg of tin powder is added into the stirring kettle every minute until all the tin powder is added;
(4) stirring-1
Stirring for 20 minutes at the rotating speed of 30 revolutions per minute;
(5) scraping arm
Scraping the material on the stirring arm of the stirrer to the stirring kettle by using a scraper;
(6) stirring-2
Stirring for 10 minutes at the rotating speed of 30 revolutions per minute;
(7) stirring in vacuum
Vacuumizing the stirring kettle to-0.08 Mpa, and stirring for 5 minutes at the rotating speed of 20 r/min;
(8) filling into cans
Taking out the solder paste in the stirring kettle, canning, and storing at 2-10 deg.C.
Compared with the prior art, the invention has the beneficial effects that: the high-reliability solder paste can be free from solder joint cracking after 2000 times of cold and hot circulation, and is high in practicability.
Detailed Description
The technical solutions in the present invention will be described clearly and completely with reference to the following embodiments of the present invention, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In the embodiment of the invention, the high-reliability solder paste comprises the following components in percentage by mass: 10-12% of soldering flux and 88-90% of SnAgCuCe series soldering tin powder.
The soldering flux comprises the following components in percentage by mass: 40-50% of rosin, 5-11% of an active agent, 20-40% of a solvent and 4-7% of a thixotropic agent.
The rosin is one or more of Clearon P-105 rosin and Foral AX-E, KE-100 rosin.
The active agent is one or more of dimer acid, pentaerythritol palmitate, diethylamine hydrobromide and FS-3100.
The solvent is one or more of diethylene glycol monoethyl ether, diethylene glycol monohexyl ether and tetrahydrofurfuryl alcohol.
The thixotropic agent is one or more of methylbenzotriazole, hydrogenated castor oil and stearic acid amide SLPACKS ZHH.
The particle size of the solder paste is 20-38 μm.
The tin powder comprises the following components in percentage by weight: tin: 96.2-99%, silver: 0.3-3.0%, copper: 0.5-0.7% of cerium and 0.01-0.05% of cerium.
A preparation method of high-reliability solder paste comprises the following steps:
first, preparation of flux paste
(1) Weighing the following components:
weighing the solvent, the rosin and the activator thixotropic agent in turn by using an electronic balance according to the designed proportion for later use;
(2) heating for dissolving:
adding the weighed solvent and rosin in the step (1) into a stainless steel reaction kettle, adjusting the heating power of the reaction kettle to heat the reaction kettle to 110 ℃ at a heating rate of about 5 ℃/s, keeping the temperature, stirring at a low speed of 50r/min in the whole process until all the components are completely dissolved, cooling the system to 90 ℃ until the system is in a clear and transparent state, adding an active agent, stopping heating and stirring after the components are completely dissolved, and performing the next step of operation;
(3) emulsification and dispersion:
when the solution in the step (2) is cooled to 80 ℃ along with the reaction kettle, adding a thixotropic agent, carrying out high-speed emulsification, controlling the emulsification rotating speed within 6000r/min, carrying out canning and standing after the emulsification is finished, cooling to room temperature, and sealing and standing for 100 hours;
(4) grinding and refining:
grinding and refining the substances which are completely cooled in the step (3) by using a stainless steel three-roller grinder, and repeatedly grinding the soldering flux for the solder paste twice;
second step, preparation of solder paste
(1) Flux paste component weighing
Precisely weighing 11.5% of flux paste and 88.5% of tin, silver, copper, cerium and tin powder;
(2) stirring soldering paste
Adding the flux paste into a stirring kettle of a solder paste stirrer, and stirring for 3 minutes at a rotating speed of 20 revolutions per minute;
(3) adding tin powder
The tin paste stirrer maintains the rotating speed of 20 revolutions per minute, and 3Kg of tin powder is added into the stirring kettle every minute until all the tin powder is added;
(4) stirring-1
Stirring for 20 minutes at the rotating speed of 30 revolutions per minute;
(5) scraping arm
Scraping the material on the stirring arm of the stirrer to the stirring kettle by using a scraper;
(6) stirring-2
Stirring for 10 minutes at the rotating speed of 30 revolutions per minute;
(7) stirring in vacuum
Vacuumizing the stirring kettle to-0.08 Mpa, and stirring for 5 minutes at the rotating speed of 20 r/min;
(8) filling into cans
Taking out the solder paste in the stirring kettle, canning, and storing at 2-10 deg.C.
The solder paste prepared in the example has no crack in the welding spot after being subjected to the cold and hot circulation of 2000 (40 ℃ below zero to 120 ℃).
It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.
Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.
Claims (9)
1. The high-reliability solder paste is characterized by comprising the following components in percentage by mass: 10-12% of soldering flux and 88-90% of SnAgCuCe series soldering tin powder.
2. The solder paste as claimed in claim 1, wherein the flux comprises the following components by mass percent: 40-50% of rosin, 5-11% of an active agent, 20-40% of a solvent and 4-7% of a thixotropic agent.
3. The solder paste as claimed in claim 2, wherein the rosin is one or more of clean P-105 rosin and Foral AX-E, KE-100 rosin.
4. The solder paste as claimed in claim 2, wherein the active agent is one or more of dimer acid, pentaerythritol palmitate, diethylamine hydrobromide, and FS-3100.
5. The high-reliability solder paste as claimed in claim 2, wherein the solvent is one or more of diethylene glycol monoethyl ether, diethylene glycol monohexyl ether and tetrahydrofurfuryl alcohol.
6. The high-reliability solder paste as claimed in claim 2, wherein the thixotropic agent is one or more of methylbenzotriazole, hydrogenated castor oil and stearic acid amide SLPACKS ZHH.
7. The solder paste of claim 1, wherein the solder paste has a particle size of 20 μm to 38 μm.
8. The solder paste as claimed in claim 1, wherein the solder powder comprises the following components in percentage by weight: tin: 96.2-99%, silver: 0.3-3.0%, copper: 0.5-0.7% of cerium and 0.01-0.05% of cerium.
9. A preparation method of high-reliability solder paste is characterized by comprising the following steps:
first, preparation of flux paste
(1) Weighing the following components:
weighing the solvent, the rosin and the activator thixotropic agent in turn by using an electronic balance according to the designed proportion for later use;
(2) heating for dissolving:
adding the weighed solvent and rosin in the step (1) into a stainless steel reaction kettle, adjusting the heating power of the reaction kettle to heat the reaction kettle to 110 ℃ at a heating rate of about 5 ℃/s, keeping the temperature, stirring at a low speed of 50r/min in the whole process until all the components are completely dissolved, cooling the system to 90 ℃ until the system is in a clear and transparent state, adding an active agent, stopping heating and stirring after the components are completely dissolved, and performing the next step of operation;
(3) emulsification and dispersion:
when the solution in the step (2) is cooled to 80 ℃ along with the reaction kettle, adding a thixotropic agent, carrying out high-speed emulsification, controlling the emulsification rotating speed within 6000r/min, carrying out canning and standing after the emulsification is finished, cooling to room temperature, and sealing and standing for 100 hours;
(4) grinding and refining:
grinding and refining the substances which are completely cooled in the step (3) by using a stainless steel three-roller grinder, and repeatedly grinding the soldering flux for the solder paste twice;
second step, preparation of solder paste
(1) Flux paste component weighing
Precisely weighing 11.5% of flux paste and 88.5% of tin, silver, copper, cerium and tin powder;
(2) stirring soldering paste
Adding the flux paste into a stirring kettle of a solder paste stirrer, and stirring for 3 minutes at a rotating speed of 20 revolutions per minute;
(3) adding tin powder
The tin paste stirrer maintains the rotating speed of 20 revolutions per minute, and 3Kg of tin powder is added into the stirring kettle every minute until all the tin powder is added;
(4) stirring-1
Stirring for 20 minutes at the rotating speed of 30 revolutions per minute;
(5) scraping arm
Scraping the material on the stirring arm of the stirrer to the stirring kettle by using a scraper;
(6) stirring-2
Stirring for 10 minutes at the rotating speed of 30 revolutions per minute;
(7) stirring in vacuum
Vacuumizing the stirring kettle to-0.08 Mpa, and stirring for 5 minutes at the rotating speed of 20 r/min;
(8) filling into cans
Taking out the solder paste in the stirring kettle, canning, and storing at 2-10 deg.C.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010302412.6A CN111347193A (en) | 2020-04-16 | 2020-04-16 | High-reliability solder paste and preparation method thereof |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010302412.6A CN111347193A (en) | 2020-04-16 | 2020-04-16 | High-reliability solder paste and preparation method thereof |
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| Publication Number | Publication Date |
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| CN111347193A true CN111347193A (en) | 2020-06-30 |
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| CN202010302412.6A Pending CN111347193A (en) | 2020-04-16 | 2020-04-16 | High-reliability solder paste and preparation method thereof |
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1385280A (en) * | 2002-07-02 | 2002-12-18 | 北京工业大学 | High creep resistance rareearth contained tin base leadless soldering-flux and preparation method thereof |
| CN1544197A (en) * | 2003-11-21 | 2004-11-10 | 北京工业大学 | Low silver lead-free solder |
| CN1657225A (en) * | 2004-12-09 | 2005-08-24 | 中国电子科技集团公司第十四研究所 | Ultra particle leadless brazing filler metal and its manufacturing method |
| CN1721124A (en) * | 2005-05-11 | 2006-01-18 | 马鑫 | Leadless solder |
| CN101642855A (en) * | 2009-08-19 | 2010-02-10 | 浙江一远电子材料研究院 | Rear-earth-containing halogen free Sn-Ag-C series tinol |
| CN105345316A (en) * | 2015-08-24 | 2016-02-24 | 江苏广昇新材料有限公司 | Novel solder paste production process |
| CN105689914A (en) * | 2016-04-08 | 2016-06-22 | 深圳市博士达焊锡制品有限公司 | Tin paste and preparation method thereof |
| CN110405377A (en) * | 2019-07-10 | 2019-11-05 | 深圳市博士达焊锡制品有限公司 | A kind of semiconductor high temperature print solder paste |
| CN110961829A (en) * | 2019-12-09 | 2020-04-07 | 青岛歌尔微电子研究院有限公司 | Soldering flux and preparation method thereof, and solder paste and preparation method thereof |
-
2020
- 2020-04-16 CN CN202010302412.6A patent/CN111347193A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1385280A (en) * | 2002-07-02 | 2002-12-18 | 北京工业大学 | High creep resistance rareearth contained tin base leadless soldering-flux and preparation method thereof |
| CN1544197A (en) * | 2003-11-21 | 2004-11-10 | 北京工业大学 | Low silver lead-free solder |
| CN1657225A (en) * | 2004-12-09 | 2005-08-24 | 中国电子科技集团公司第十四研究所 | Ultra particle leadless brazing filler metal and its manufacturing method |
| CN1721124A (en) * | 2005-05-11 | 2006-01-18 | 马鑫 | Leadless solder |
| CN101642855A (en) * | 2009-08-19 | 2010-02-10 | 浙江一远电子材料研究院 | Rear-earth-containing halogen free Sn-Ag-C series tinol |
| CN105345316A (en) * | 2015-08-24 | 2016-02-24 | 江苏广昇新材料有限公司 | Novel solder paste production process |
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| CN110405377A (en) * | 2019-07-10 | 2019-11-05 | 深圳市博士达焊锡制品有限公司 | A kind of semiconductor high temperature print solder paste |
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Application publication date: 20200630 |
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