CN106271177B - A kind of interconnection solder and its interconnection manufacturing process - Google Patents
A kind of interconnection solder and its interconnection manufacturing process Download PDFInfo
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- CN106271177B CN106271177B CN201610847725.3A CN201610847725A CN106271177B CN 106271177 B CN106271177 B CN 106271177B CN 201610847725 A CN201610847725 A CN 201610847725A CN 106271177 B CN106271177 B CN 106271177B
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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
-
- 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
- B23K1/00—Soldering, e.g. brazing, or unsoldering
- B23K1/06—Soldering, e.g. brazing, or unsoldering making use of vibrations, e.g. supersonic vibrations
-
- 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
- B23K2101/00—Articles made by soldering, welding or cutting
- B23K2101/36—Electric or electronic devices
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Electric Connection Of Electric Components To Printed Circuits (AREA)
- Wire Bonding (AREA)
Abstract
The present invention provides a kind of interconnection solder and its interconnection manufacturing process, the heating process temperature of its product applied of interconnection solder is T, and component A, fusing point component B less than T, fusing point of the interconnection solder comprising fusing point more than T are more than the third phase component C of T；The third phase component C accounts for the 0 ~ 30% of the quality summation of component A, component B, third phase component C；It reacts to form compound A at a temperature of the heating process between wherein component A and component BxBy；The ratio between amount of substance of the component A and component B is more than x/y, and the third phase component C and component A, component B do not react, and the hardness of the third phase component C is less than component A, component B and compound AxByHardness.Technical scheme of the present invention can also adjust the Young's modulus and coefficient of thermal expansion of connector while obtaining high-melting-point welding point by adjusting the ratio of each component in solder.
Description
Technical field
The invention belongs to field of material technology more particularly to a kind of interconnection solder and its interconnection manufacturing process.
Background technology
In recent years, the elastic braids such as SiC, GaN, InP semiconductor replaces Si to answer extensively with its superior electronics conversion performance
Use the fields such as automotive electronics, great power LED.These electronic devices can work in the environment of higher than 250 DEG C and keep excellent
Good characteristic.On the other hand, microelectronic chip is bonded towards miniaturization, high density, excellent electromechanical properties direction high speed development,
So that the quantity of heat production of its unit area is increased considerably, by material heat conductivility itself limited these heats can not timely with outside
Boundary swaps, and causes the operating temperature of chip higher and higher.
All the time, due to Sn-Pb eutectic alloys have good electric conductivity, thermal conductivity, antifatigue stability and compared with
Low price and surface tension, and be widely used in Electronic Packaging domain variability and occupy leading position for a long time.Especially in aviation
High power high-temperature module in the high-precision pointed collar domain such as space flight, geological drilling, military affairs is still respectively 310 DEG C and 305 using fusing point
DEG C Pb-5Sn and Pb-10Sn high lead solders as connecting material.In order to comply with the unleaded trend of consumer electronics, meet people
Growing Science & Technology Demands realize that the research of high-temperature electronic encapsulation lead-free and application are that world's electronic industry faces in recent years
Urgent project, related scholar and researcher all over the world are made that unremitting effort thus.
On the basis of traditional die mounts, high-temperature electronic encapsulation method continue to develop, developed at present to be formed with
Lower four high temperature connection methods：The methods of high-temp leadless solder, Transient liquid phase method, nanoparticles sinter and solid phase Direct Bonding.
In order to replace dystectic high lead solder, people to expand the research of high-temp leadless solder first and achieve certain achievement,
Following several systems are wherein primarily formed, such as：Au based alloys, Zn based alloys, Sn-Sb etc..Common Au based alloys have Au-
Sn, Au-Ge and Au-Si etc., wherein Au-20Sn are the high-temp solder to attract attention earliest, eutectic point and high lead solder fusing point
It is very close.Although Au based alloys have higher intensity, electrical and thermal conductivity performance, Au based alloy hardness is higher, processing performance
It is poor, easy to produce larger stress, the price is very expensive by what is more important Au, considerably increases cost of material, application
Field be restricted.Although Zn based alloy costs are relatively low, processing temperature is higher to be easy to damage chip, and
Its mechanical property, electric property and high-temperature performance are to be improved.Although Sn-Sb alloys have good profit to copper surface
It is moist, but Sn-Sb alloy melting points are relatively low（230 DEG C or so）, it is very difficult to apply in secondary back, therefore grinding for the alloy
Study carefully and using relatively fewer.
Secondly, for the sintering of nano particle and solid phase Direct Bonding, generally apply in its sintering process certain
Pressure is easy to cause chip the damage of unrepairable.The manufacturing process of nano particle is complex, single yield is relatively low and compared with
High porosity makes the sintering of nano particle receive challenge, and its sintered structure property differs larger with reguline metal,
Still the approval of industry is hardly resulted in.Solid phase Direct Bonding does not receive extensive attention also as emerging bonding method, although
It is protected when making using high vacuum environment, and only more can not to obtain densification excellent in cavity in the migration connector of thermal stress
Good connector.
Transient liquid phase method makes solder middle layer melt and diffusion reaction occurs with substrate and generates high-melting-point gold by heating
The connector for belonging to compound, to have stronger high temperature repellence.But due to the Young's modulus of compound it is larger with substrate and
There are larger coefficient of thermal expansion mismatch problems to be run up in thermal stress certain by long-term elevated temperature thermal cycles for chip
The limit, it is easy to the stripping of chip and substrate be caused to fail.For the higher field of reliability requirement, if it is in application process
It is middle to crack, not only result in huge economic loss, it is also possible to lead to catastrophic consequence.
In addition, the formation of traditional Transient liquid phase method high-melting-point interconnection solder joint relies primarily on the atoms permeating under high temperature,
Atom at least will be by the weld size of half, and this adds increased the time loss in process.Particularly, as Ni originals
For the slower material of sub- diffusion velocity, time loss is undoubtedly at critical defect.Therefore, ensureing to obtain high-melting-point interconnection
On the basis of solder joint, how to overcome and solve the time loss of Transient liquid phase method is a difficult point.In addition to this, current solder weldering
The high problem of Young's modulus for connecing rear weld seam is the difficult point of current chip package, even more hinders the important of scientific and technological progress process of industrialization
Factor is current various countries crucial problem urgently to be resolved hurrily.
Invention content
For the above technical problem, the invention discloses a kind of interconnection solder and its interconnection manufacturing process, using interconnection pricker
The connector that material is formed realizes the controllable of Young's modulus and coefficient of thermal expansion under atmospheric environment, and provides a kind of interconnection forming side
The problem of method, assists rapid shaping, and the present invention not only solves Transient liquid phase method time-consuming, can also adjust the Young of connector
Modulus makes it that thermal stress caused by chip heat production be avoided to fail.
In this regard, the technical solution adopted by the present invention is：
The heating process temperature of a kind of interconnection solder, the product applied is T, and the interconnection solder is more than comprising fusing point
The component B of component A, fusing point less than T, the fusing point of T are more than the third phase component C of T；The third phase component C accounts for component A, component
B, the 0 ~ 30% of the quality summation of third phase component C；Between wherein component A and component B shape is reacted at a temperature of the heating process
At compound AxBy；The ratio between amount of substance of the component A and component B is more than x/y, the third phase component C and component A, component
B does not react, and the hardness of the third phase component C is less than component A, component B and compound AxByHardness.Wherein, group
It is metallic particles to divide A, component B.Wherein, compound AxByIn x and y value depending on the characteristic of component A and component B,
AxByPerformance is stablized at temperature T；The ratio between amount of substance of the component A and component B is more than x/y, i.e. the amount of component A enough will
The amount of component B all consumes, and forms compound AxBy, and the amount of component A can have it is extra.In this way so that using this interconnection
The connector that solder is formed is dystectic connector, to have stronger high temperature repellence.Preferably, the third phase component C
For graininess, the metal or metallic compound of T are more than for fusing point.
Using this technical solution, it is inclined as the way and technology of solder main component using alloy to change the prior art
See, using the component A and component B of separated different melting points, component A and component B have specific surface area more higher than alloy, can be with
It is preferably contacted with soldered surface, and compound A is formed by component A and component BxBy, reduce the diffusion path of atom,
To solve the problems, such as that Transient liquid phase method time loss is grown.
In addition, in order to reduce the Young's modulus of full compound connector solve the problems, such as with the thermal expansion matching of chip and substrate,
The ratio of component A in interconnection solder can be increased, or further add in interconnecting solder that appropriate hardness is smaller not to participate in reaction
Third phase component C.In addition, in order to obtain single high melting compound connector, it can be by the ratio root of component A, component B in solder
According to the composition control of its compound in reasonable range, and cancel the addition of third phase component C.
Application environment and problem of the technical scheme of the present invention according to high temperature power electronic product, by being added in solder
Metallic particles component A reduces the diffusion path of atom, to solve the problems, such as that Transient liquid phase method time loss is grown.In addition, general
The tissue Young's modulus for the full compound connector that Transient liquid phase method obtains is higher, is easy due to thermal stress under long-term thermal shock
Cracking, the present invention can interconnect the ratio of component A in solder by increase, or further add appropriate hardness in interconnecting solder
The smaller third phase component C for not participating in reaction, not only greatly reduces the Young's modulus of connector, Young's modulus is reduced to originally
15% ~ 40%, also have both possessed by ordinary couplings the advantages that fusing point is high, air-tightness is good, defect is few, intensity is high, good conductivity,
It can apply, be specially adapted in third generation elastic braid semiconductor packaging process under the environment such as high temperature, ultrasound.
As a further improvement on the present invention, the component B includes Sn, and the component A is at least one in Ni, Ag, Cu, Au
Kind, the third phase particle is at least one of Al, Mg, graphene.
As a further improvement on the present invention, the surface of the third phase component C is coated in Ag, Au or Sn at least one
Kind.Using this technical solution, so that the solders such as third phase component C particles and Sn are well combined.
As a further improvement on the present invention, the component A is Ni, and the component B includes Sn, the AxByCompound is
Ni3Sn4。
As a further improvement on the present invention, the component A is Cu, and the component B is Sn, the AxByCompound is
Cu6Sn5Or Cu3Sn。
As a further improvement on the present invention, the component A is Ag, and the component B is Sn, the AxByCompound is
Ag3Sn。
As a further improvement on the present invention, the component A is Au, and the component B is Sn, the AxByCompound is
AuSn4、AuSn2Or AuSn.
As a further improvement on the present invention, the compound AxByThe nucleocapsid knot for the A@B that component A is constituted is surrounded for component B
Structure.Using this technical solution, the metal material of the nucleocapsid for the A@B that component A and component B reactions generate in solder reduces original
The diffusion path of son solves the problems, such as Transient liquid phase method time loss length；And the Young's modulus of connector is greatly reduced,
Also have both possessed by ordinary couplings the advantages that fusing point is high, air-tightness is good, defect is few, intensity is high, good conductivity, can high temperature,
It applies, is specially adapted in third generation elastic braid semiconductor packaging process under the environment such as ultrasound.As further changing for the present invention
Into the component A, component B and component C are spherical, sheet or at least one of rodlike.
As a further improvement on the present invention, the interconnection solder also includes scaling powder.
The present invention also provides a kind of interconnection manufacturing process, it is characterised in that：It uses interconnection solder as described above will
Base material one and base material three link together.
As a further improvement on the present invention, the interconnection manufacturing process includes the following steps：
Step S1：Base material one and base material three are surface-treated；
Step S2：The interconnection solder is put into as middle layer two between base material one, base material three and forms sandwich structure,
And the sandwich structure is fixed using fixing component；
Step S3：Fixing component is heated using heating device, so that middle layer two is melted by heat transfer；Using pressure
Apparatus for adjusting force applies pressure to base material one and keeps sandwich structure, and 3 ~ 60s is kept the temperature at a temperature of the heating process, then
It keeps being cooled to room temperature under above-mentioned pressure.
Preferably, the chip material of the targeted base material one of the above method is Si, SiC, GaN, InP, GaAs etc., the chip back of the body
Face can carry out monometallic coating or the processing of more coats of metal as needed.Wherein, described Si, SiC, GaN, InP, GaAs are normal
Chip material.
The fusing point that is had using the connector that the method obtains is high, air-tightness is good, defect is few, intensity is high, good conductivity etc. is excellent
Point realizes the connection of hot interface or electrical connection between chip and substrate, has good conductive, heat conductivility, be conducive to chip
The raising of performance；It can apply, be specially adapted in third generation elastic braid semiconductor packaging process under the environment such as high temperature, ultrasound.
As a further improvement on the present invention, in step S2, when being heated to fixing component using heating device, to institute
It states sandwich structure and applies oscillator field or ultrasonic field.Using this technical solution, apply ultrasonic field, ultrasonic " cavitation " and " acoustic streaming "
Effect will further increase the diffusion velocity of atom, and the cavitation bubble that ultrasound generates will produce part in the moment of compression blasting
High temperature and high pressure environment, the diffusion reaction between solder provides enough energy, meanwhile, the explosion of cavitation bubble also will produce microbeam
Stream, the compound that reaction is generated are removed from metal surface, promote the further reaction for being exposed metal.Laser field is introduced, is swashed
What the high-energy density of light, good directionality can orient inputs a large amount of energy into weld seam, accelerates the process of reaction.
As a further improvement on the present invention, the time for applying oscillator field or ultrasonic field no more than the heating when
Between.
As a further improvement on the present invention, in step S1, it is described to base material one and base material three carry out surface treatment include：
It is first polished respectively the connection surface of base material one, base material three, is then cleaned by ultrasonic.
Preferably, first the connection surface of base material one, base material three with fine sandpaper slightly polish and remove the oxidation on surface
Layer and greasy dirt impurity.
As a further improvement on the present invention, 10 ~ 30 DEG C of fusing point of the temperature of the heating higher than component B.Using this
Technical solution prevents the too low excessively high damage to chip of unfused and temperature for causing solder of temperature.
As a further improvement on the present invention, the interconnection solder is pre- tabletting structure or paste.Using this technical solution,
Different process conditions are adapted to be operated.
As a further improvement on the present invention, in step S2, the sandwich structure is first subjected to precompressed, then using solid
Determine component to fix the sandwich structure.In this way, can pressure size be determined according to the size reasonable of required weld seam in advance.
As a further improvement on the present invention, the heating device can be induction heating apparatus, microwave heating equipment or heat
At least one of air heating device.
As a further improvement on the present invention, the base material one and three equal horizontal cross of base material are placed；The base material three with
Fixing device is fixedly connected, and the outside of the base material one is contacted with pressure-regulating device.Using this technical solution, it is conveniently operated,
And the effect of welding is good.
As a further improvement on the present invention, the fixing component is fixture, and the surface of the fixture is equipped with groove, described
Groove shapes are consistent with base material three, and the boundary dimensions of the groove is more than 0.1 ~ 0.2mm of the boundary dimensions of base material three, described recessed
The depth of slot is smaller 0.3 ~ 0.8mm than the thickness of base material three.Using this technical solution, fixed structure is with good stability.
Technical scheme of the present invention is mainly accelerated reaction speed, is reduced time loss using two kinds of effective measures.First,
If nucleocapsid metal material is formed only with metal mixed grain fraction A and component B or component A and component B, due to these solders
So that low-melting component B is greatly reduced at a distance from high melting point component A, by adjusting the particle of high melting point component A in solder
Size and content ensure completely consuming for high melting point component A, achieve the purpose that high-melting-point interconnects solder joint.
Compared with prior art, present invention has the advantages that：
First, interconnection solder using the present invention, according to high temperature power electronic product application environment and problem, by
The diffusion path that metallic particles component A reduces atom is added in solder, solves the Transient liquid phase method time loss of the prior art
Long problem；The connector that high melting point metal compound can be formed simultaneously, to have stronger high temperature repellence.
Second, technical scheme of the present invention can solve full compound connector Young's modulus by simple effective method
The higher and unmatched problem of substrate coefficient of thermal expansion.It is possible, firstly, to by change solder in high melting point component A ratio or,
Adjust component A, the ratio of component B forms the thickness of each metal layer in nucleocapsid metal material A@B to control acquisition to adjust
Connector is full compound connector or the mixing high temperature connector of compound and high melting point component A.High melting point component A's deposits in connector
The Young's modulus of connector will be being reduced to a certain extent, improve the performance of connector.Secondly, if the high melting point component in connector
A can not still obtain ideal Young's modulus connector, and it is smaller and do not participate in the third phase component of reaction that hardness can be added into solder
C, such as the smaller higher melting-point metal of Al, Mg hardness can also add graphene to adjust the thermal expansion system of connector into solder
Number, reaches the matched well with substrate.
Third, the interconnection solder and its interconnection manufacturing process of technical scheme of the present invention can be connected under atmospheric environment
Connect, overcome certain solder high temperature, high vacuum processing environment, simplify production technology, improve production efficiency, reduce and be produced into
This, is conducive to industrialization large-scale production, and manufactured solder paste is convenient for the printing on substrate, compatible with existing packaging technology
Property is good.
4th, no pressure or low-pressure may be implemented in the interconnection solder and its interconnection manufacturing process of technical scheme of the present invention
Under welding, avoid causing damage to chip due to applying larger pressure to chip, it is easy to operate flexibly, not by workpiece size
With the limitation of shape, while be adapted to large scale, large-area substrates and it is heat sink between connection.
5th, technical scheme of the present invention can be welded by the thickness of the thickness or sheet solder that print solder paste to control
Size is stitched, best soldering effect is reached, the strength of joint height of acquisition, good leak tightness, wetability is good, welded rate is high, especially suitable
In requisition for the application scenario of long-time vacuum pressure-resistant seal, high service temperature, high intensity and adverse circumstances.
Description of the drawings
Fig. 1 is the schematic diagram that the present invention is assembled using interconnection solder to being connected material.
Fig. 2 is the microstructure schematic diagram of present invention interconnection solder.
Fig. 3 is the microstructure schematic diagram that the nucleocapsid that the present invention is formed when heated is mixed with third phase particle.
Fig. 4 is the connection diagram of the interconnection manufacturing process of the present invention.
Reference numeral is：1- base materials one, 2- middle layers two, 3- base materials three, 4- fixtures, 5- pressure-regulating devices, 21- components
A, 22- component B, 23- third phase component C, 24- scaling powder.
Specific implementation mode
Below in conjunction with the accompanying drawings, the preferably embodiment of the present invention is described in further detail.
Embodiment 1
Shown in Fig. 1, Fig. 2 and Fig. 4, a kind of method that high melting compound connector is realized under atmospheric environment, the connection
Method includes the following steps：
I, it is surface-treated to being connected material：To the connection surface 1200# sand paper sand of base material 1 and base material 33
Paper carries out the oxide layer and greasy dirt impurity on slight polishing removal surface, immerse later ethanol solution carry out ultrasonic cleaning 3 ~
5min；
II, base material 33 is placed in lower layer, base material 1 is placed in upper layer and middle layer 22 in a kind of sandwich knot of pilot process
Structure, base material 1 and 33 equal horizontal cross of base material are placed.Above-mentioned base material 1 used is chip, chip material Si, SiC, GaN,
InP or GaAs, chip back coated metal are Ni, and Ni layer thickness is 8 μm；Base material 33 is pure Ni substrates, thickness 1mm.
Middle layer 22 used in the step is determined as Sn-27 wt.%Ni hybrid particles prickers according to chip back coating and substrate
Material, i.e. component A are Ni, and component B is Sn, wherein the quality of component A accounts for the 27% of the quality summation of component A, component B.Wherein Sn,
The grain size of Ni is respectively 40 μm and 10 μm, and adds suitable scaling powder and be made in Ni substrates of the paste coated in base material 33.
III, the sandwich structure of composition is placed and is fixed in the fixture 4 of design；Fixture 4 is equipped with inside groove, the inside groove
Shape is consistent with base material 33, and length and width size is less than mother more than the length of base material 33,0.1 ~ 0.2mm of width, depth
33 thickness 0.5mm of material.
IV, fixture 4 is heated using heating device, so that middle layer 22 is reached scheduled fusing temperature by heat transfer
Degree；Heating device used should be equipped with temperature measurement and reponse system, and set heating temperature is higher than 10 ~ 30 DEG C of the fusing point of Sn, institute
It can be sensing heating, microwave heating or Hot-blast Heating etc. to state heating device.
V, pressure is applied to base material 1 using pressure-regulating device 5 and keeps the close contact of sandwich structure and predetermined
At a temperature of keep the temperature the regular hour；Pressure size, about 1MPa are determined according to the size reasonable of required weld seam；Keep above-mentioned pressure
Under the premise of be cooled to room temperature.As shown in Fig. 2, the component A 21 of middle layer 22, component B 22, third phase component C 23, helping weldering
Agent 24 is dispersed in system.
Above-mentioned interconnection manufacturing process is achieved that interconnection within 30 minutes.The connector obtained by test, the present embodiment
Qiang Du >50MPa, the good airproof performance of structure, Fu Yiwendu >400 DEG C, weld seam Young's modulus is 150 ~ 170GPa.Using existing
The solder of the Sn-Ni alloys of technology, and use traditional Transient liquid phase method formed high-melting-point interconnection solder joint generally require 1 hour with
On, and the intensity of connector is less than 40MPa.
This method can largely reduce the diffusion length of Sn simultaneously by adding suitable Ni particles in solder
Increase the contact area with Ni, the component A and component B forms Ni at high temperature3Sn4, greatly reduce generation compound
To the inhibition of metal counterdiffusion, by elapsed time by control in several hours within dozens of minutes.The method is easy to operate,
Without special protection, cost is relatively low, joint performance is good, can adapt to the application requirement of various harsh environments.Wink after improvement
State liquid phase method, while having both high-melting-point and electric conductivity, the shortening reaction time that can increase improves production efficiency, in vapour
There is extremely important actual application prospect in vehicle electronics, great power LED constant power electronics.
Embodiment 2
Shown in attached drawing 1, Fig. 2 and Fig. 4, high melting compound and refractory metal are fast implemented under a kind of atmospheric environment
Hybrid juction connection method, which includes the following steps：
I, material is connected to be surface-treated：To the connection surface of base material 1 and base material 33 with 1200# sand paper by its
Surface polishes and removes the greasy dirt impurity on surface, immerses ethanol solution later and is cleaned by ultrasonic 3 ~ 5min.
II, base material 33 is placed in lower layer, base material 1 is placed in upper layer and middle layer 22 in a kind of sandwich knot of pilot process
Structure, base material 1 and 33 equal horizontal cross of base material are placed.Above-mentioned base material 1 used is chip, chip material Si, SiC, GaN,
InP or GaAs, chip back coated metal are Ni, 8 μm of Ni layer thickness；Base material 33 is pure Ni substrates, thickness 1mm.In used
Interbed 22 is determined according to chip back coating and substrate uses Sn-30 wt.%Ni hybrid particles solders, i.e. component A is Ni, group
It is Sn to divide B, wherein the quality of component A accounts for the 30% of the quality summation of component A, component B.The wherein particle size difference of Sn, Ni
For 40 μm and 10 μm, and adds suitable scaling powder and be made in Ni substrates of the paste coated in base material 33.
III, the sandwich structure of composition is placed and is fixed in the fixture 4 of design；Fixture 4 is equipped with inside groove, the inside groove
Shape is consistent with base material 33, and length and width size is less than mother more than the length of base material 33,0.1 ~ 0.2mm of width, depth
33 thickness 0.5mm of material.
IV, fixture 4 is heated using heating device, so that middle layer 22 is reached scheduled fusing temperature by heat transfer
Degree；Wherein, heating device used should be equipped with temperature measurement and reponse system, and set heating temperature is higher than the fusing point 10 ~ 30 of Sn
℃；The heating device can be sensing heating, microwave heating or Hot-blast Heating etc..
V, pressure is applied to base material 1 using pressure-regulating device 5 and keeps the close contact of sandwich structure and predetermined
At a temperature of keep the temperature the regular hour；Pressure size, about 1MPa are determined according to the size reasonable of required weld seam；Keep above-mentioned pressure
Under the premise of be cooled to room temperature.
Above-mentioned interconnection manufacturing process is achieved that interconnection within 10-30 minutes.By test, what the present embodiment obtained connects
The Qiang Du > of head;50MPa, the good airproof performance of structure, Fu Yiwendu >400 DEG C, weld seam Young's modulus is 60GPa.And use existing skill
The method of art, solder are that obtain the Young's modulus of weld seam be 150GPa for the solder paste of Ni+Sn mixing, and the intensity of connector is less than
40MPa.It can be seen that weld seam Young's modulus substantially reduces, the intensity of connector is improved.
This method is Ni particles in right amount by being added in solder, can largely reduce the diffusion length of Sn simultaneously
Increase with the contact area of Ni, greatly reduce the inhibition for generating compound to metal counterdiffusion, by elapsed time by
Within several hours control dozens of minutes（This case is 10-30 minutes）.In addition, increase solder in Ni content, make its with Sn
While reaction completely and there are certain remnants, achievees the purpose that reduce weld seam Young's modulus, Young's modulus is reduced by 150GPa
To 60GPa.The connector that the interconnection manufacturing process of this example obtains, can also be to a certain degree while having both high-melting-point with electric conductivity
The Young's modulus of upper control weld seam, before having extremely important practical application in automotive electronics, great power LED constant power electronics
Scape.
Embodiment 3
Shown in Fig. 1 and Fig. 4, high melting compound, refractory metal and third are fast implemented under a kind of atmospheric environment
The connection method of phase metal mixed tissue connector, the connection method include the following steps：
I, material is connected to be surface-treated：To the connection surface of base material 1 and base material 33 with 1200# sand paper by its
Surface polishes and removes the greasy dirt impurity on surface, immerses ethanol solution later and is cleaned by ultrasonic 3 ~ 5min.
II, base material 33 is placed in lower layer, base material 1 is placed in upper layer and middle layer 22 in a kind of sandwich knot of pilot process
Structure, base material 1 and 33 equal horizontal cross of base material are placed.Above-mentioned base material 1 used is chip, chip material Si, SiC, GaN,
InP or GaAs, chip back coated metal are Ni, 8 μm of Ni layers of thickness；Base material 33 is pure Ni substrates, thickness 1mm.
Wherein, middle layer 22 used is determined as Sn-20 wt.%Ni-10 wt.%Al according to chip back coating and substrate
Hybrid particles solder, i.e. component A are Ni, and component B is Sn, and third phase grain fraction C is Al, wherein component A, component B, third
The percentage that the quality of phase grain fraction C accounts for the quality summation of component A, component B, third phase grain fraction C respectively is respectively
20%,70%,10%.The grain size of wherein Sn, Ni, Al are respectively 40 μm, 10 μm, 20 μm, and add suitable scaling powder and paste is made
In Ni substrates coated in base material 33.
III, the sandwich structure of composition is placed and is fixed in the fixture 4 of design；Fixture 4 is equipped with inside groove, the inside groove
Shape is consistent with base material 33, and length and width size is less than mother more than the length of base material 33,0.1 ~ 0.2mm of width, depth
33 thickness 0.5mm of material.
IV, fixture 4 is heated using heating device, so that middle layer 22 is reached scheduled fusing temperature by heat transfer
Degree；Wherein, heating device used should be equipped with temperature measurement and reponse system, and set heating temperature is higher than the fusing point 10 ~ 30 of Sn
℃；The heating device can be sensing heating, microwave heating or Hot-blast Heating etc..
V, pressure is applied to base material 1 using pressure-regulating device 5 and keeps the close contact of sandwich structure and predetermined
250 DEG C of temperature at keep the temperature one hour within；Pressure size, about 1MPa are determined according to the size reasonable of required weld seam；In holding
It is cooled to room temperature under the premise of stating pressure.
Above-mentioned interconnection manufacturing process is achieved that interconnection in one hour.The nucleocapsid formed when heating and third phase
The microstructure schematic diagram of grain mixing is as shown in Figure 3.As shown in figure 3, during heating, the component A 21 of middle layer 22, group
B 22 is divided to form nucleocapsid, the gaps between nucleocapsid third phase component C 23, scaling powder 24 is dispersed therein.
Pass through the Qiang Du > for the connector that test, the present embodiment obtain;50MPa, the good airproof performance of structure, Fu Yiwendu >400
DEG C, weld seam Young's modulus is 20GPa.And the method for using the prior art, solder are the obtained weldering of the solder paste of Ni+Sn mixing
The Young's modulus of seam is 150GPa, and the intensity of connector is less than 40MPa.It can be seen that weld seam Young's modulus substantially reduces.
This method is Ni particles in right amount by being added in solder, can largely reduce the diffusion length of Sn simultaneously
Increase with the contact area of Ni, greatly reduce the inhibition for generating compound to metal counterdiffusion, by elapsed time by
A few hours were controlled within one hour.The content for increasing Ni in solder, makes it while being reacted completely with Sn and has certain
Remnants achieve the purpose that reduce weld seam Young's modulus.Importantly, the Al particles being added do not react with the Sn in solder
And be retained in inside weld seam, the Young's modulus of joint microstructure is greatly reduced in the case where not influencing fusing point, is reduced to
20GPa reaches the matched well of chip and substrate.The connector that the interconnection manufacturing process of this example obtains is having both high-melting-point and conduction
While property, the Young's modulus of weld seam can be also controlled to a certain extent, in automotive electronics, great power LED constant power electronics
There is extremely important actual application prospect.
Embodiment 4
Shown in attached drawing 1, Fig. 2 and Fig. 4, the connection side of high melting compound connector is fast implemented under a kind of atmospheric environment
Method, the connection method include the following steps：
I, material is connected to be surface-treated：To the connection surface of base material 1 and base material 33 with 1200# sand paper by its
Surface polishes and removes the greasy dirt impurity on surface, immerses ethanol solution later and is cleaned by ultrasonic 3 ~ 5min.
II, base material 33 is placed in lower layer, base material 1 is placed in upper layer and middle layer 22 in a kind of sandwich knot of pilot process
Structure, base material 1 and 33 equal horizontal cross of base material are placed.Above-mentioned base material 1 used is chip, chip material Si, SiC, GaN,
InP or GaAs, chip back coated metal are Ni, and Ni layers of thickness is 8 μm；Base material 33 is pure Ni substrates, thickness 1mm.
Wherein, middle layer 22 used is determined as Sn-24 wt.%Ni hybrid particles prickers according to chip back coating and substrate
Material, i.e. component A are Ni, and wherein for Sn, the percentage that component A accounts for the quality summation of component A, component B is respectively 24% to component B.Its
The grain size of middle Sn, Ni are respectively 40 μm and 10 μm, and add suitable scaling powder and the Ni substrates that paste is coated in base material 33 are made
On.
III, the sandwich structure of composition is placed and is fixed in the fixture 4 of design；Fixture 4 is equipped with inside groove, the inside groove
Shape is consistent with base material 33, and length and width size is less than mother more than the length of base material 33,0.1 ~ 0.2mm of width, depth
33 thickness 0.5mm of material.
IV, fixture 4 is heated using heating device, so that middle layer 22 is reached scheduled fusing temperature by heat transfer
Degree；Wherein, heating device used should be equipped with temperature measurement and reponse system, and set heating temperature is higher than the fusing point 10 ~ 30 of Sn
℃；The heating device can be sensing heating, microwave heating or Hot-blast Heating etc..
V, certain pressure is applied to base material 1 using pressure-regulating device 5 and keeps the close contact of sandwich structure simultaneously
2 ~ 20s of welding is assisted to weld seam using ultrasonic generator.Pressure size is determined according to the size reasonable of required weld seam, about
1MPa。
VI, after the completion of ultrasound applies, ultrasonic generator vehicle is gone and stops heating, is let to slowly cool to room temperature.
Above-mentioned steps V act on base material 33 in reflux course, using ultrasonic generator, not to base material 1
Any pressure is generated, ultrasound, which applies, completes postcooling.
Above-mentioned interconnection manufacturing process is achieved that interconnection in ten seconds.By test, the present embodiment obtain connector it is strong
Spend 60MPa, the good airproof performance of joint structure, Fu Yiwendu >400 DEG C, weld seam Young's modulus is 150 ~ 170GPa.Using existing skill
The solder of the Sn-Ni alloys of art, and use traditional Transient liquid phase method formed high-melting-point interconnection solder joint generally require 1 hour with
On, and the intensity of connector is less than 40MPa.This method can be led under the booster action of ultrasonic wave, in chip-underlying structure
The diffusion length of atom can be reduced, accelerate reaction speed by crossing design of material, also be acted on by " cavitation " and " acoustic streaming " of ultrasound,
Make Sn reacted with Ni generate compound from Ni sur-face peelings, accelerate the formation of intermetallic compound, can tens of seconds when
The interior high-melting-point connector for generating the full compound of high-melting-point or compound and remnants Ni compositions.Obtained connector has high intensity（40~
60MPa）, high leakproofness, wide service temperature, high stability, the characteristics such as high conductivity.With traditional Transient liquid phase method a few hours
Time is compared, and this method can be completed within tens of seconds, and the welding point generated has higher shear strength and conduction
Performance meets the application requirement of third generation elastic braid semiconductor.
Embodiment 5
The component A for interconnecting solder is Cu, and component B is Sn, and third phase grain fraction C is Mg, wherein third phase grain fraction
The percentage that the quality of C accounts for the quality summation of component A, component B, third phase grain fraction C is 10%.Wherein, the component A
Amount enough all consumes the amount of component B, forms compound Cu6Sn5。
Other methods step is the same as embodiment 1.
Interconnection is achieved that in five ten minutes using above-mentioned interconnection manufacturing process.By test, the present embodiment obtains
Connector intensity 40MPa, the good airproof performance of joint structure, Fu Yiwendu >400 DEG C, weld seam Young's modulus is 25GPa.Using
The weld seam Young's modulus that the method and solder of the prior art obtain is 150GPa, it can be seen that, weld seam Young's modulus substantially reduces.
Embodiment 6
The component A for interconnecting solder is Au, and component B is Sn, and third phase grain fraction C is graphene, wherein third phase particle
The percentage that the quality of component C accounts for the quality summation of component A, component B, third phase grain fraction C respectively is 30%.Wherein, described
The amount of component A enough all consumes the amount of component B, forms compound AuSn4、AuSn2Or AuSn.
Other methods step is the same as embodiment 4.
Interconnection is achieved that in 40 minutes using above-mentioned interconnection manufacturing process.By testing, what the present embodiment obtained
The intensity 35MPa of connector, the good airproof performance of joint structure, Fu Yiwendu >400 DEG C, weld seam Young's modulus is 20GPa.Using existing
There is the method for technology and weld seam Young's modulus that solder obtains be 150GPa, it can be seen that, weld seam Young's modulus substantially reduces.
The above content is a further detailed description of the present invention in conjunction with specific preferred embodiments, and it cannot be said that
The specific implementation of the present invention is confined to these explanations.For those of ordinary skill in the art to which the present invention belongs, exist
Under the premise of not departing from present inventive concept, a number of simple deductions or replacements can also be made, all shall be regarded as belonging to the present invention's
Protection domain.
Claims (9)
1. a kind of interconnection solder, it is characterised in that：The heating process temperature of its product applied is T, the interconnection solder packet
The component B of component A, fusing point less than T, fusing point containing fusing point more than T are more than the third phase component C of T；The third phase component C is accounted for
0 ~ 30% and third phase component C of the quality summation of component A, component B, third phase component C is not 0；Wherein component A and group
Divide to react at a temperature of the heating process between B and forms compound AxBy；The ratio between amount of substance of the component A and component B is big
It does not react in x/y, the third phase component C and component A, component B, the hardness of the third phase component C is less than component
A, component B and compound AxByHardness；The component B includes Sn, and the component A is at least one of Ni, Ag, Cu, Au,
The third phase component C is at least one of Al, Mg, graphene.
2. interconnection solder according to claim 1, it is characterised in that：The compound AxByComponent A structures are surrounded for component B
At A@B nucleocapsid.
3. interconnection solder according to claim 1, it is characterised in that：The surface of the third phase component C is coated with Ag, Au
Or at least one of Sn.
4. interconnection solder according to claim 1, it is characterised in that：The component A is Ni, and the component B includes Sn, institute
State AxByCompound is Ni3Sn4。
5. interconnection solder according to claim 1, it is characterised in that：When the component A is Cu, the component B is Sn, institute
State AxByCompound is Cu6Sn5Or Cu3Sn；When the component A is Ag, the component B is Sn, the AxByCompound is Ag3Sn；
When the component A is Au, the component B is Sn, the AxByCompound is AuSn4、AuSn2Or AuSn.
6. interconnection solder according to claim 1, it is characterised in that：The component A, component B and component C are spherical, piece
Shape is at least one of rodlike；The interconnection solder also includes scaling powder.
7. a kind of interconnection manufacturing process, it is characterised in that：It uses the interconnection solder as described in claim 1 ~ 6 any one will
Base material one and base material three link together comprising following steps：
Step S1：Base material one and base material three are surface-treated；
Step S2：The interconnection solder is put into as middle layer two between base material one, base material three and forms sandwich structure, and is adopted
The sandwich structure is fixed with fixing component；
Step S3：Fixing component is heated using heating device, so that middle layer two is melted by heat transfer；Using pressure tune
Regulating device applies pressure to base material one and keeps sandwich structure, and 3 ~ 60s is kept the temperature at a temperature of the heating process, then keeps
It is cooled to room temperature under above-mentioned pressure.
8. interconnection manufacturing process according to claim 7, it is characterised in that：In step S3, using heating device to fixation
When component is heated, oscillator field or ultrasonic field are applied to the sandwich structure.
9. interconnection manufacturing process according to claim 7, it is characterised in that：The interconnection solder is pre- tabletting structure or cream
Shape；The heating device can be at least one of induction heating apparatus, microwave heating equipment or hot air heating apparatus；The base material
One and three equal horizontal cross of base material place；The base material three is fixedly connected with fixing device, the outside of the base material one and pressure
Regulating device contacts.
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| JP6897237B2 (en) * | 2017-03-31 | 2021-06-30 | 三菱マテリアル株式会社 | Molded body for joining and its manufacturing method |
| JP7016015B2 (en) * | 2017-05-09 | 2022-02-04 | パナソニックＩｐマネジメント株式会社 | Mounting structure |
| CN107096988B (en) * | 2017-05-11 | 2019-05-03 | 哈尔滨理工大学 | It is a kind of quickly to prepare electronic package material Cu3The method of Sn intermetallic compound |
| CN108465892B (en) * | 2018-02-05 | 2020-08-07 | 东莞市新玛博创超声波科技有限公司 | Fluxing agent-free ultrasonic low-temperature brazing method for copper-based material under atmospheric condition and application |
| CN109759742B (en) * | 2019-03-13 | 2024-03-26 | 重庆理工大学 | Solder for soldering flux-free and soldering method |
| CN110153592B (en) * | 2019-06-20 | 2021-12-28 | 常熟理工学院 | In-Ni system brazing filler metal and preparation method thereof |
| CN111014864B (en) * | 2019-12-10 | 2022-04-01 | 太原理工大学 | Preparation method for joint with directional grain brazing seam through rapid ultrasonic-assisted manufacturing |
| CN111151836B (en) * | 2020-01-13 | 2021-12-24 | 中国船舶重工集团公司第七二五研究所 | Connection method and application of high-temperature superconducting tape |
| CN112191968B (en) * | 2020-10-14 | 2022-05-10 | 哈尔滨工业大学（深圳） | Packaging method for enhancing metallurgy of nano solder interface |
| CN114559180B (en) * | 2022-03-21 | 2024-04-09 | 太原理工大学 | Silicon carbide particle reinforced magnesium alloy brazing filler metal and preparation method and application thereof |
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