CN114700653A - High-hardness all-intermetallic compound welding spot and preparation method thereof - Google Patents
High-hardness all-intermetallic compound welding spot and preparation method thereof Download PDFInfo
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- CN114700653A CN114700653A CN202210398136.7A CN202210398136A CN114700653A CN 114700653 A CN114700653 A CN 114700653A CN 202210398136 A CN202210398136 A CN 202210398136A CN 114700653 A CN114700653 A CN 114700653A
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- 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
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- 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
- B23K31/00—Processes relevant to this subclass, specially adapted for particular articles or purposes, but not covered by only one of the preceding main groups
- B23K31/02—Processes relevant to this subclass, specially adapted for particular articles or purposes, but not covered by only one of the preceding main groups relating to soldering or welding
-
- 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
- B23K2101/00—Articles made by soldering, welding or cutting
- B23K2101/36—Electric or electronic devices
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- Resistance Welding (AREA)
Abstract
The invention relates to a high-hardness all-intermetallic compound welding spot and a preparation method thereof, belonging to the field of electronic packaging. The method comprises the steps of accurately proportioning metal raw materials according to a proportion; sealing the Cu, Co, Sn and In components, placing the sealed tubes In a heat treatment furnace at 800 ℃ for heat preservation for 24 hours, shaking the tubes for many times In the midway to ensure the uniformity of alloy components, and cooling the tubes to room temperature to obtain a solder; the alloy solder was then sandwiched between two high purity copper plates and placed on an electrical heating plate for soldering at 300 c for 24 hours. The invention prepares a high-hardness full intermetallic compound welding spot by optimizing the components of the alloy solder and the welding process, and provides a new idea for preparing the welding spot. The prepared all-intermetallic compound welding spot mainly comprises (Cu, Co)6(Sn,In)5And (Cu, Co)3Two phases of (Sn, In) with high hardness, the elastic modulus of which is 130.7GPa and 141.7GPa respectively, and the hardness of which is 8.54GPa and 7.39GPa respectively.
Description
Technical Field
The invention relates to a high-hardness all-intermetallic compound welding spot and a preparation method thereof, belonging to the field of electronic packaging.
Background
With the development of electronic devices toward miniaturization, high temperature resistance, high service reliability and high power density, a new generation of wide bandgap semiconductor device becomes a development trend, which puts higher requirements on electronic packaging connectors matched with the wide bandgap semiconductor device. The transient liquid phase bonding technique combines diffusion soldering and brazing processes, i.e. at a certain temperature and pressure, the substrate and the molten solder interact, elements diffuse between low melting point materials (such as Sn, In) and high melting point materials (such as Cu, Ag), and all liquid interlayer metals are consumed after isothermal solidification to form all intermetallic compounds. Because the melting point of the full intermetallic compound is higher, the intermetallic compound of the primary bonding can not be melted in the secondary bonding process, the thermally stable structure is maintained, the effects of low-temperature preparation and high-temperature service are achieved, and the development trend of the current electronic device is met. Due to the wide application of the copper matrix and the tin-based solder, the research of the transient liquid phase connecting material of the Cu-Sn system has important significance.
According to the research of the prior literature on the Cu-Sn system full intermetallic compound welding spot, the composition phase mainly comprises Cu6Sn5And Cu3Sn, Yang Pingfeng et al use nanoindentation method to measure Cu6Sn5And Cu3The elastic modulus of Sn is 116.89 + -2.04 GPa and 133.39 + -4.44 GPa respectively, and the hardness is 6.35 + -0.20 GPa and 6.32 + -0.15 GPa respectively. By adding other alloy elements into the Cu-Sn system, the composite all-intermetallic compound welding spot can be prepared, so that the performance of the welding spot is changed. Abu Zayed Mohammad Saliqur Rahman et al, obtained by Cu/Ni/Sn system (Cu, Ni)6Sn5The elastic modulus and the hardness measured by using the nano-indentation are 110.80 +/-5.05 GPa and 7.43 +/-0.57 GPa respectively, so that the hardness of the welding spot is improved. Lee et al believe that the addition of Co can significantly increase Cu6Sn5The shearing strength of the welding spot, the refining of the welding spot tissue, the improvement of the wettability and the reduction of the electromigration resistance and the supercooling degree. The addition of In can reduce the melting point of the solder, and Wei Huang et al use the first principle to calculate and prove that Cu6(Sn,In)5Has an elastic modulus greater than that of Cu6Sn5And the Pugh ratio (volume modulus/shear modulus) is relatively large, and the toughness is better. Therefore, Co and In are added into the Cu-Sn system to transportObtaining a full intermetallic compound solder joint by transient liquid phase bonding, the solder joint composition phase comprises (Cu, Co)6(Sn,In)5And (Cu, Co)3(Sn, In), which has important significance for improving mechanical properties such as hardness of the all-intermetallic compound welding spot.
Disclosure of Invention
The invention aims to provide a high-hardness all-intermetallic compound welding spot and a preparation method thereof. According to the invention, the high-hardness full intermetallic compound welding spot is prepared by optimizing the alloy solder components and the welding process, and a new thought is provided for the preparation of the welding spot. The prepared all-intermetallic compound welding spot mainly comprises (Cu, Co)6(Sn,In)5And (Cu, Co)3Two phases of (Sn, In) with high hardness, the elastic modulus of which is 130.7GPa and 141.7GPa respectively, and the hardness of which is 8.54GPa and 7.39GPa respectively.
The purpose of the invention is realized by the following technical scheme:
a high-hardness all-intermetallic compound solder joint needs solder components as follows: cu, Co, Sn and In respectively account for a%, b%, c and d In percentage by mass, wherein a is less than or equal to 2, b is less than or equal to 8, d is less than or equal to 50, and c is 100-a-b-d.
A preparation method of a high-hardness full intermetallic compound welding spot comprises the following steps:
step one, batching: the components of Cu, Co, Sn and In are proportioned according to the component scheme by adopting industrial pure metal elements (the purity is more than 99.9%).
Step two, preparing solder: and (3) sealing the Cu, Co, Sn and In components In the step one In a closed quartz glass tube, putting the quartz glass tube into a heat treatment furnace at 800 ℃ for heat preservation for 24 hours, shaking for about 6 times midway to ensure that the components are uniformly mixed, and then cooling to room temperature In air to obtain the required solder.
Step three, welding: and (3) removing oil stains on the surfaces of two copper plates, keeping the copper plates clean, placing one copper plate on an electric heating plate, taking a proper amount of the welding flux obtained in the step two, placing the welding flux on the copper plate, covering the other copper plate above the welding flux after the welding flux is melted to form a sandwich structure, and welding the copper plate on the electric heating plate at the temperature of 300 ℃ for 24 hours to obtain the high-hardness full intermetallic compound welding spot.
Advantageous effects
1. Compared with the traditional full Cu of a Cu-Sn system, the full intermetallic compound welding spot prepared by the invention6Sn5+Cu3The Sn intermetallic compound solder joint has higher hardness.
2. The all-intermetallic compound welding spot provided by the invention is prepared from common metal materials, and the preparation method is simple, easy to operate, low in environmental requirement, safe and economic in application and the like.
Drawings
FIG. 1 is an SEM image of a copper plate and solder after soldering for 24 hours at 300 ℃;
FIG. 2 is a nano-indentation load-displacement curve along the transverse direction of an all-intermetallic compound solder joint.
Detailed Description
The technical solution of the present invention is further explained with reference to the accompanying drawings and embodiments.
Example 1
The solder components Cu, Co, Sn and In required by the high-hardness all-intermetallic compound welding spot are respectively a%, b%, c and d In percentage by mass, wherein a is 1.0, b is 4.8, c is 47.9 and d is 46.3.
The method for preparing the all-intermetallic compound welding spot comprises the following steps:
the method comprises the following steps: selecting pure metal materials Cu, Co, Sn and In with the purity higher than 99.9 percent for later use.
Step two: and (3) weighing the metals Cu, Co, Sn and In the first step according to the mass percentage of the solder required by the high-hardness full intermetallic compound welding spot, putting the weighed raw materials into a crucible, heating the crucible In a heat treatment furnace at 400 ℃ for 10 minutes, taking out the crucible, and cooling the crucible to room temperature In the air to obtain the ingot.
Step three: and (4) sealing the ingot obtained in the step two into a sealed quartz glass tube, placing the sealed quartz glass tube into a heat treatment furnace at 800 ℃, shaking once every 4 hours to uniformly mix the quartz glass tube, keeping the temperature for 24 hours, taking out the quartz glass tube, and cooling the quartz glass tube to room temperature in the air to obtain the solder alloy.
Step four: and (3) starting an electric heating plate, setting the temperature to be 300 ℃, removing oil stains on the surfaces of two copper plates, keeping the two copper plates clean, placing one copper plate on the electric heating plate, dipping a proper amount of the solder alloy obtained in the third step into a small amount of soldering flux, placing the solder alloy on the copper plate, ensuring that the solder alloy is fully paved on the surface of the copper plate after being heated and melted and the thickness of the copper plate is not more than 50 mu m, covering the other copper plate on the solder to form a sandwich structure, placing the copper plate at 300 ℃ for 24 hours, and then cooling the copper plate to room temperature to obtain the high-hardness all-intermetallic compound welding spot.
SEM and EDS detection and nano-indentation mechanical property analysis are carried out on the all-intermetallic compound welding spot, and the welding spot is detected to comprise (Cu, Co)6(Sn,In)5And (Cu, Co)3Two (Sn, In) phases with (Cu, Co) as the middle part6(Sn,In)5The upper and lower sides are (Cu, Co)3(Sn, In) having elastic moduli of 130.7GPa and 141.7GPa, respectively, and hardnesses of 8.54GPa and 7.39GPa, respectively.
Example 2
The solder components Cu, Co, Sn and In required by the high-hardness all-intermetallic compound welding spot are respectively a%, b%, c% and d% by mass, wherein a is 1.0, b is 6.5, c is 47.0 and d is 45.5.
The method for preparing the all-intermetallic compound welding spot comprises the following steps:
the method comprises the following steps: selecting pure metal materials Cu, Co, Sn and In with the purity higher than 99.9 percent for later use.
Step two: and (3) weighing the metals Cu, Co, Sn and In the first step according to the mass percentage of the solder required by the high-hardness full intermetallic compound welding spot, putting the weighed raw materials into a crucible, heating the crucible In a heat treatment furnace at 400 ℃ for 10 minutes, taking out the crucible, and cooling the crucible to room temperature In the air to obtain the ingot.
Step three: and (4) sealing the ingot obtained in the step two into a sealed quartz glass tube, placing the sealed quartz glass tube into a heat treatment furnace at 800 ℃, shaking once every 4 hours to uniformly mix the quartz glass tube, keeping the temperature for 24 hours, taking out the quartz glass tube, and cooling the quartz glass tube to room temperature in the air to obtain the solder alloy.
Step four: and (3) starting an electric heating plate, setting the temperature to be 300 ℃, removing oil stains on the surfaces of two copper plates, keeping the two copper plates clean, placing one copper plate on the electric heating plate, dipping a proper amount of the solder alloy obtained in the third step into a small amount of soldering flux, placing the solder alloy on the copper plate, ensuring that the solder alloy is fully paved on the surface of the copper plate after being heated and melted and the thickness of the copper plate is not more than 50 mu m, covering the other copper plate on the solder to form a sandwich structure, placing the copper plate at 300 ℃ for 24 hours, and then cooling the copper plate to room temperature to obtain the high-hardness all-intermetallic compound welding spot.
SEM and EDS detection and nano-indentation mechanical property analysis are carried out on the all-intermetallic compound welding spot, and the welding spot is detected to comprise (Cu, Co)6(Sn,In)5And (Cu, Co)3Two (Sn, In) phases with (Cu, Co) as the middle part6(Sn,In)5The upper and lower sides are (Cu, Co)3(Sn, In) having elastic moduli of 119.4GPa and 147.3GPa, respectively, and hardnesses of 7.96GPa and 7.44GPa, respectively. .
Example 3
The solder components Cu, Co, Sn and In required by the high-hardness all-intermetallic compound welding spot are respectively a%, b%, c% and d% by mass, wherein a is 2.0, b is 5.5, c is 47.0, and d is 45.5.
The method for preparing the all-intermetallic compound welding spot comprises the following steps:
the method comprises the following steps: selecting pure metal materials Cu, Co, Sn and In with the purity higher than 99.9 percent for later use.
Step two: and (2) weighing the metals of Cu, Co, Sn and In the first step according to the mass percentage of the solder required by the high-hardness full intermetallic compound welding spot, putting the weighed raw materials into a crucible, heating the crucible In a heat treatment furnace at 400 ℃ for 10 minutes, taking out the crucible, and cooling the crucible to room temperature In the air to obtain an ingot.
Step three: and (4) sealing the ingot obtained in the second step into a sealed quartz glass tube, placing the sealed quartz glass tube into a heat treatment furnace at 800 ℃, shaking the sealed quartz glass tube once every 4 hours to uniformly mix the sealed quartz glass tube, keeping the temperature for 24 hours, taking out the sealed quartz glass tube, and cooling the sealed quartz glass tube to room temperature in the air to obtain the solder alloy.
Step four: and (3) starting an electric heating plate, setting the temperature to be 300 ℃, removing oil stains on the surfaces of two copper plates, keeping the two copper plates clean, placing one copper plate on the electric heating plate, dipping a proper amount of the solder alloy obtained in the third step into a small amount of soldering flux, placing the solder alloy on the copper plate, ensuring that the solder alloy is fully paved on the surface of the copper plate after being heated and melted and the thickness of the copper plate is not more than 50 mu m, covering the other copper plate on the solder to form a sandwich structure, placing the copper plate at 300 ℃ for 24 hours, and then cooling the copper plate to room temperature to obtain the high-hardness all-intermetallic compound welding spot.
Performing SEM, EDS detection and nano-indentation mechanical property analysis on the full intermetallic compound welding spot to determine that the welding spot comprises (Cu, Co)6(Sn,In)5And (Cu, Co)3Two (Sn, In) phases with (Cu, Co) as the middle part6(Sn,In)5The upper and lower sides are (Cu, Co)3(Sn, In) having elastic moduli of 125.5GPa and 138.7GPa, respectively, and hardnesses of 8.26GPa and 7.40GPa, respectively.
The above detailed description is intended to illustrate the objects, aspects and advantages of the present invention, and it should be understood that the above detailed description is only exemplary of the present invention and is not intended to limit the scope of the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (2)
1. A high-hardness all-intermetallic compound welding spot and a preparation method thereof are disclosed, wherein the welding flux required for preparing all-intermetallic compounds is composed of four elements of Cu, Co, Sn and In, the mass percentages of the Cu, Co, Sn and In are respectively a%, b%, c% and d%, wherein a is less than or equal to 2, b is less than or equal to 8, d is less than or equal to 50, and c is 100-a-b-d.
2. The method of producing a high-hardness all-intermetallic compound solder joint according to claim 1, characterized in that: the method comprises the following steps:
step one, batching: proportioning Cu, Co, Sn and In components by adopting industrial pure metal elements according to the component scheme;
step two, preparing solder: sealing the four components in the step one into a closed quartz glass tube, putting the quartz glass tube into a heat treatment furnace at 800 ℃ for heat preservation for 24 hours, shaking for many times in the midway to ensure that the components are uniformly mixed, and then cooling to room temperature in the air to obtain the required solder;
step three, welding: and (3) removing oil stains on the surfaces of two copper plates, keeping the copper plates clean, placing one copper plate on an electric heating plate, taking a proper amount of the welding flux obtained in the step two, placing the welding flux on the copper plate, covering the other copper plate above the welding flux after the welding flux is melted to form a sandwich structure, and welding the copper plate on the electric heating plate at the temperature of 300 ℃ for 24 hours to obtain the high-hardness full intermetallic compound welding spot.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20070071634A1 (en) * | 2005-09-26 | 2007-03-29 | Indium Corporation Of America | Low melting temperature compliant solders |
| JP2011005542A (en) * | 2009-06-23 | 2011-01-13 | Nihon Superior Co Ltd | In-CONTAINING LEAD-FREE SOLDER ALLOY, AND SOLDERED JOINT USING THE SOLDER |
| CN103658899A (en) * | 2013-12-04 | 2014-03-26 | 哈尔滨工业大学深圳研究生院 | Method for preparing and applying single orientation Cu6Sn5 intermetallic compound micro-interconnecting welding point structure |
| CN107538149A (en) * | 2017-10-25 | 2018-01-05 | 郑州轻工业学院 | A kind of Sn Cu Co Ni lead-free solders and preparation method thereof |
| CN108588456A (en) * | 2018-04-26 | 2018-09-28 | 哈尔滨工业大学深圳研究生院 | A kind of Cu-Sn intermetallic compounds skeleton phase-change material and preparation method thereof |
-
2022
- 2022-04-13 CN CN202210398136.7A patent/CN114700653A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20070071634A1 (en) * | 2005-09-26 | 2007-03-29 | Indium Corporation Of America | Low melting temperature compliant solders |
| JP2011005542A (en) * | 2009-06-23 | 2011-01-13 | Nihon Superior Co Ltd | In-CONTAINING LEAD-FREE SOLDER ALLOY, AND SOLDERED JOINT USING THE SOLDER |
| CN103658899A (en) * | 2013-12-04 | 2014-03-26 | 哈尔滨工业大学深圳研究生院 | Method for preparing and applying single orientation Cu6Sn5 intermetallic compound micro-interconnecting welding point structure |
| CN107538149A (en) * | 2017-10-25 | 2018-01-05 | 郑州轻工业学院 | A kind of Sn Cu Co Ni lead-free solders and preparation method thereof |
| CN108588456A (en) * | 2018-04-26 | 2018-09-28 | 哈尔滨工业大学深圳研究生院 | A kind of Cu-Sn intermetallic compounds skeleton phase-change material and preparation method thereof |
Non-Patent Citations (3)
| Title |
|---|
| BYUNG SUK LEE 等: ""Cu-Sn Intermetallic Compound Joints for High-Temperature Power Electronics Applications"", 《JOURNAL OF ELECTRONIC MATERIALS》 * |
| JUNG-SUB LEE 等: ""Formation and characterization of cobalt-reinforced Sn-3.5Ag solder"", 《ELECTRONIC COMPONSENTS AND TECHNOLOGY CONFERENCE》 * |
| WEI HUANG 等: ""Effect of In-Doping on Mechanical Properties of Cu6Sn5-Based Intermetallic Compounds A First-Principles Study"", 《JOURNAL OF ELECTRONIC MATERIALS》 * |
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Application publication date: 20220705 |