Sn-Bi system composite brazing filler metal for electronic packaging and preparation method thereof

A technology for electronic packaging and composite brazing filler metal, applied in manufacturing tools, welding equipment, metal processing equipment, etc., can solve the problems of poor reliability of brazing joints and reduced alloy ductility, and avoid graphene floating and shearing. The effect of strength improvement and shear strength improvement

Active Publication Date: 2017-08-04
HARBIN INST OF TECH
View PDF6 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0006] The present invention aims to solve the problem of the reduction of alloy ductility caused by the hard and brittle Bi-rich phase in Sn-58Bi solder, and the poor reliability of brazed joints caused by excessively thick intermetallic compounds in the remelting service and aging process problem, and provide a kind of Sn-Bi system composite solder for electronic packaging and preparation method thereof

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Sn-Bi system composite brazing filler metal for electronic packaging and preparation method thereof
  • Sn-Bi system composite brazing filler metal for electronic packaging and preparation method thereof
  • Sn-Bi system composite brazing filler metal for electronic packaging and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

specific Embodiment approach 1

[0018] Specific embodiment one: a kind of Sn-Bi system composite solder for electronic packaging in this embodiment is made up of reinforcement and Sn-58Bi solder; The mass fraction of reinforcement in the Sn-Bi system composite solder for described electronic packaging is: 0.005%-0.5%; the reinforcement is graphene-supported nano-scale cerium oxide or graphene-supported micro-scale cerium oxide, and the mass fraction of graphene in the reinforcement is 30%-90%.

specific Embodiment approach 2

[0019] Specific embodiment two: the difference between this embodiment and specific embodiment one is: the particle size of graphene in the graphene-supported nano-scale cerium oxide is 2-10 μm, the thickness is 20-50 nm, and the particle size of nano-scale cerium oxide is 10-20nm; the particle size of the graphene in the graphene-supported micron-sized cerium oxide is 2-10 μm, the thickness is 20-50 nm, and the particle size of the micron-sized cerium oxide is 2-5 μm. Others are the same as the first embodiment.

specific Embodiment approach 3

[0020] Embodiment 3: This embodiment differs from Embodiment 1 or Embodiment 2 in that: the mass fraction of the reinforcement in the Sn—Bi-based composite solder for electronic packaging is 0.01%. Others are the same as those in Embodiment 1 or 2.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
particle diameteraaaaaaaaaa
thicknessaaaaaaaaaa
particle diameteraaaaaaaaaa
Login to view more

Abstract

The invention discloses Sn-Bi system composite brazing filler metal for electronic packaging and a preparation method of the Sn-Bi system composite brazing filler metal. The problems that alloy ductility is lowered due to the Bi-rich phase with the hard brittle property in Sn-58Bi brazing filler metal and the reliability of a brazing filer metal connector becomes poor due to an excessively thick intermetallic compound in the remelting service and aging process are solved. The method comprises the steps that a graphene/cerium oxide composite enhanced body is prepared; 2, the enhanced body and a brazing filler metal base body are subjected to ball milling and mixed; 3, flux paste is added into the enhanced body and the brazing filler metal to be stirred to be uniform; and 4, the mixture is placed into a crucible and heated at the temperature of 180 DEG C, taken out, poured into a mold and cooled, and therefore a composite brazing filler metal block is obtained. According to the composite brazing filler metal, the welding spot microstructure is refined, the hardness of the brazing filler metal is greatly improved, the thickness of the intermetallic compound in the interface between the brazing filler metal and the base body is reduced, and therefore the shear strength of the welding spot is improved. The preparation method is used for preparing the Sn-Bi system composite brazing filler metal.

Description

technical field [0001] The invention relates to a Sn-Bi composite solder for electronic packaging and a preparation method thereof. Background technique [0002] The interconnection material used in microelectronic welding technology is the material basis for reliable connection of solder joints. For a long time, Sn-Pb solder has been widely used in the field of electronic packaging for decades due to its advantages of low cost, good mechanical properties, strong electrical conductivity, good process performance and good solderability. However, Pb is harmful to human health and the natural environment. Many countries have proposed relevant laws and regulations to prohibit the use of Pb in recent years. In this case, lead-free solder has become the current mainstream trend. [0003] With the continuous improvement of electronic packaging technology, the size of micro-solder joints required in the field of micro-connection is also getting smaller and smaller. Sexuality is at...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): B23K35/26B23K35/40
CPCB23K35/26B23K35/40
Inventor 修子扬武高辉陈国钦姜龙涛蒋涵张强杨文澍
Owner HARBIN INST OF TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products