Effect of interfacial strength between Cu6Sn5 and Cu3Sn intermetallics on the brittle fracture failure of lead-free solder joints with OSP pad finish

2011 ◽  
Author(s):  
Chaoran Yang ◽  
Fubin Song ◽  
S. W. Ricky Lee
Keyword(s):  
Brittle Fracture ◽  
Solder Joints ◽  
Interfacial Strength ◽  
Lead Free ◽  
Lead Free Solder ◽  
Fracture Failure ◽  
Free Solder

Plastic Strain Distribution as a Precursor for Transition From Ductile to Brittle Failure in Lead-Free Solder Joints

2009 ◽  
Author(s):  
Feng Gao ◽  
Jianping Jing ◽  
Frank Z. Liang ◽  
Richard L. Williams ◽  
Jianmin Qu
Keyword(s):  
Brittle Fracture ◽  
Plastic Strain ◽  
Solder Joint ◽  
Failure Mode ◽  
Strain Distribution ◽  
Solder Joints ◽  
Lead Free ◽  
Lead Free Solder ◽  
Loading Rates ◽  
Free Solder

One of the major failure modes in lead-free solder joints is the brittle fracture at the solder/Cu pad interface under dynamic loading conditions. Such brittle fracture often leads to catastrophic premature failure of portable electronic devices. Therefore, it is desirable to design the package and the solder joints in such a way that brittle interfacial fracture can be avoided during drop test. To develop such design guidelines, we studied in this paper the dynamic failure of a single solder joint (SSJ). The SSJs with different geometry and substrate surface finish were prepared by laser-cutting from a BGA package assembled on a printed circuit board (PCB). The SSJs were tested under various shear loading rates, ranging from 5 mm/s to 500 mm/s. In conjunction with the experimental tests, finite element analyses (FEA) of these SSJ samples subjected to various loading rates were also conducted. Results from both experimental testing and numerical simulations show that the distribution of plastic strain near the solder/IMC interface is a key indictor of the failure mode. For a given sample geometry and loading rate, if the maximum solder plastic strain lies near the solder/IMC interface, the failure will be more likely to be ductile failure within the solder alloy. On the other hand, if the maximum plastic strain is mainly located at the edge of the interface between solder and the IMC layer with very little plasticity within the solder near the interface, brittle fracture of the IMC/Cu interface will be more likely to occur. Since numerically computing the plastic strain distribution in a solder joint is much easier than predicting joint failure, results of this study provide us with an effective means to predict the type of failure mode of a solder joint under dynamic loading.

Void Formation and Their Effect on Reliability of Lead-Free Solder Joints on MID and PCB Substrates

2017 ◽  
Vol 66 (4) ◽  
pp. 1229-1237 ◽  
Author(s):  
P. Wild ◽  
T. Grozinger ◽  
D. Lorenz ◽  
A. Zimmermann
Keyword(s):  
Solder Joints ◽  
Void Formation ◽  
Lead Free ◽  
Lead Free Solder ◽  
Free Solder

Quantitative Evaluation of Voids in Lead Free Solder Joints

2015 ◽  
Vol 772 ◽  
pp. 284-289 ◽  
Author(s):  
Sabuj Mallik ◽  
Jude Njoku ◽  
Gabriel Takyi
Keyword(s):  
Solder Bump ◽  
Solder Joints ◽  
Void Formation ◽  
Lead Free ◽  
Lead Free Solder ◽  
Solder Paste ◽  
X Ray ◽  
Size And Shape ◽  
Solder Bumps ◽  
Free Solder

Voiding in solder joints poses a serious reliability concern for electronic products. The aim of this research was to quantify the void formation in lead-free solder joints through X-ray inspections. Experiments were designed to investigate how void formation is affected by solder bump size and shape, differences in reflow time and temperature, and differences in solder paste formulation. Four different lead-free solder paste samples were used to produce solder bumps on a number of test boards, using surface mount reflow soldering process. Using an advanced X-ray inspection system void percentages were measured for three different size and shape solder bumps. Results indicate that the voiding in solder joint is strongly influenced by solder bump size and shape, with voids found to have increased when bump size decreased. A longer soaking period during reflow stage has negatively affectedsolder voids. Voiding was also accelerated with smaller solder particles in solder paste.

Retarding Electromigration in Lead-Free Solder Joints by Alloying and Composite Approaches

2012 ◽  
Vol 42 (2) ◽  
pp. 280-287 ◽  
Author(s):  
Ran Zhao ◽  
Limin Ma ◽  
Yong Zuo ◽  
Sihan Liu ◽  
Fu Guo
Keyword(s):  
Solder Joints ◽  
Lead Free ◽  
Lead Free Solder ◽  
Free Solder
Sign in / Sign up

Export Citation Format

Share Document