scholarly journals Effective Solder for Improved Thermo-Mechanical Reliability of Solder Joints in a Ball Grid Array (BGA) Soldered on Printed Circuit Board (PCB)

2020 ◽  
Vol 50 (1) ◽  
pp. 263-282
Author(s):  
Joshua A. Depiver ◽  
Sabuj Mallik ◽  
Emeka H. Amalu
Keyword(s):  
Thermal Cycling ◽  
Solder Joints ◽  
Ball Grid Array ◽  
Temperature Cycling ◽  
The Other ◽  
Lead Free ◽  
Creep Model ◽  
Mechanical Reliability ◽  
Printed Circuit ◽  
Isothermal Ageing

AbstractBall grid array (BGA) packages have increasing applications in mobile phones, disk drives, LC displays and automotive engine controllers. However, the thermo-mechanical reliability of the BGA solder joints challenges the device functionality amidst component and system miniaturisation as well as wider adoption of lead-free solders. This investigation determines the effective BGA solders for improved thermo-mechanical reliability of the devices. It utilised a conducted study on creep response of a lead-based eutectic Sn63Pb37 and four lead-free Tin–Silver–Copper (SnAgCu) [SAC305, SAC387, SAC396 and SAC405] solders subjected to thermal cycling loadings and isothermal ageing. The solders form the joints between the BGAs and printed circuit boards (PCBs). ANSYS R19.0 package is used to simulate isothermal ageing of some of the assemblies at − 40°C, 25°C, 75°C and 150°C for 45 days and model the thermal cycling history of the other assemblies from 22°C ambient temperature for six cycles. The response of the solders is simulated using the Garofalo-Arrhenius creep model. Under thermal ageing, SAC396 solder joints demonstrate possession of least strain energy density, deformation and von Mises stress in comparison to the other solders. Under thermal cycle loading conditions, SAC405 acquired the lowest amount of the damage parameters in comparison. Lead-free SAC405 and SAC387 joints accumulated the lowest and highest energy dissipation per cycle, respectively. It is concluded that SAC405 and SAC396 are the most effective solders for BGA in devices experiencing isothermal ageing and temperature cycling during operation, respectively. They are proposed as the suitable replacement of eutectic Sn63Pb37 solder for the various conditions.

Creep Behavior of Lead Free Solder Interconnects in Microelectronic Packages: Impression Creep Testing and Constitutive Modeling

2005 ◽  
Author(s):  
I. Dutta ◽  
D. Pan ◽  
S. Jadhav ◽  
R. Mahajan
Keyword(s):  
Creep Behavior ◽  
Solder Joints ◽  
Ball Grid Array ◽  
Creep Testing ◽  
Lead Free ◽  
Creep Model ◽  
Impression Creep ◽  
Creep Response ◽  
Microelectronic Packages ◽  
Free Solder

The creep behavior of ball grid array (BGA) or flip-chip (FC) solder joints during thermo-mechanical cycling associated with service often limits the reliability of microelectronic packages. In addition, the fine intermetallic precipitates (Ag3Sn and/or Cu6Sn5) in the microstructures of the new lead-free solders (Sn-Ag and Sn-Ag-Cu) can undergo significant in situ strain-enhanced coarsening during TMC, resulting in in-service evolution of the creep behavior of the joints. Since there are significant microstructural/ compositional differences between bulk solder samples and tiny microelectronic solder joints, it is critical to develop accurate creep testing methodologies on tiny life-sized solder joints and microstructurally adaptive constitutive creep models for the emerging Pb-free solder alloys. In this paper, we present creep data obtained from tests conducted on individual Sn4Ag0.5Cu ball grid array (BGA) solder balls attached to a packaging substrate, using a newly developed miniaturized impression creep apparatus, which affords high test throughput with minimal sample preparation. Coarsening of intermetallic particles is demonstrated to influence creep behavior in two ways. At low stresses, the creep rate increases proportionately with precipitate size. At high stresses, precipitate coarsening influences creep response by altering the threshold stress for particle-limited creep. Based on the experimental observations, a microstructurally adaptive creep model, which accounts for the effects of coarsening on the creep response of solder joints, and is capable of adjusting itself as solder joint microstructures evolve during service, is presented, along with experimental determination of the relevant coarsening kinetics parameters.

Rapid Temperature Cycling (RTC) Methodology for Reliability Assessment of Solder Interconnection in Tape Ball Grid Array (TBGA) Assembly

2005 ◽  
Vol 127 (4) ◽  
pp. 466-473 ◽  
Author(s):  
B. L. Chen ◽  
X. Q. Shi ◽  
G. Y. Li ◽  
K. H. Ang ◽  
Jason P. Pickering
Keyword(s):  
Solder Joints ◽  
Reliability Assessment ◽  
Ball Grid Array ◽  
Temperature Cycling ◽  
Rapid Temperature ◽  
Reliability Of Solder Joints ◽  
Solder Joint Fatigue ◽  
Time Required ◽  
Failure Location

In this study, a thermoelectric cooler-based rapid temperature cycling (RTC) testing method was established and applied to assess the long term reliability of solder joints in tape ball grid array (TBGA) assembly. This RTC testing methodology can significantly reduce the time required to determine the reliability of electronic packaging components. A three-parameter Weibull analysis characterized with a parameter of failure free time was used for assembly reliability assessment. It was found that the RTC not only speedily assesses the long-term reliability of solder joints within days, but also has the similar failure location and failure mode observed in accelerated temperature cycling (ATC) test. Based on the RTC and ATC reliability experiments and the modified Coffin-Manson equation, the solder joint fatigue predictive life can be obtained. The simulation results were found to be in good agreement with the test results from the RTC. As a result, a new reliability assessment methodology was established as an alternative to ATC for the evaluation of long-term reliability of electronic packages.

Thermal Cycling Reliability of Chip Resistor Lead Free Solder Joints

2003 ◽  
Author(s):  
N. Islam ◽  
J. C. Suhling ◽  
P. Lall ◽  
T. Shete ◽  
H. S. Gale ◽  
...  
Keyword(s):  
Solder Joint ◽  
Thermal Cycling ◽  
Fatigue Resistance ◽  
Solder Joints ◽  
Lead Free ◽  
Lead Free Solder ◽  
Snagcu Alloy ◽  
Temperature Ranges ◽  
Free Solder

In this study, we have examined the thermal cycling reliability of several lead free chip resistor solder joint configurations. Five sizes of resistors (2512, 1206, 0805, 0603, 0402), 2 temperature ranges (−40 to 125°C and −40 to 150°C), and five different solder types have been examined. The solders include the normal SnAgCu alloy recommended by earlier studies (95.5Sn-3.8Ag-0.7Cu), and several variations that include small percentages of Bismuth and Indium to enhance fatigue resistance. Results have been compared to data for standard 63Sn-37Pb joints.

Mechanical Reliability and Bump Degradation of ACF Flip Chip Packages Using BCB (Cyclotene™) Bumping Dielectrics Under Temperature Cycling

2004 ◽  
Vol 126 (2) ◽  
pp. 202-207 ◽  
Author(s):  
Woon-Seong Kwon ◽  
Hyoung-Joon Kim ◽  
Kyung-Wook Paik ◽  
Se-Young Jang ◽  
Soon-Min Hong
Keyword(s):  
Fracture Surface ◽  
Thermal Cycling ◽  
Flip Chip ◽  
Dissimilar Materials ◽  
Damage Mechanism ◽  
Temperature Cycling ◽  
Mechanical Reliability ◽  
Cyclic Shear ◽  
Electrical Failure ◽  
Anisotropic Conductive Adhesive

Interface degradation between dissimilar materials in the flip chip packages with anisotropic conductive adhesive joint is susceptible to mechanical and electrical failure upon temperature cycling. Particularly the mechanical reliability of flip chip using anisotropic conductive films (ACFs) often depends upon the interface characteristics between the bumping/passivation dielectrics and adjacent materials. This paper investigates the delamination and cracking in polymeric bumping/passivation dielectrics (Cyclotene™ 4024) and the damage mechanism of interconnect bump with BCB bumping dielectrics upon temperature cycling. Adhesion and fracture surface morphology after die shear testing show that the weakening and delamination of BCB passivation layer at the die corner is the main cause of the reduction of die adhesion strength after the thermal cycling. The sliding trace on fracture surface after three-point bending fracture reveals that cyclic shear displacement in a polymeric BCB layer fatigue the interface bonding or interconnect bump upon thermal cycling, leading to mechanical delamination and functional bump failure. Passivation cracks also develop around the circumference of BCB passivation over aluminum pad. A model is presented for the degradation of interconnect bump with surrounding BCB passivation.

RELIABILITY EVALUATION OF BGA SOLDER JOINTS DURING ACCELERATED LIFE TEST

2006 ◽  
Vol 20 (25n27) ◽  
pp. 4553-4558
Author(s):  
OUK SUB LEE ◽  
NO HOON MYOUNG ◽  
DONG HYEOK KIM ◽  
MAN JAE HUR ◽  
SI WOON HWANG
Keyword(s):  
Solder Joint ◽  
Thermal Cycling ◽  
Solder Joints ◽  
Coefficient Of Thermal Expansion ◽  
Accelerated Life Test ◽  
Lead Free ◽  
Lead Free Solder ◽  
Metal Fatigue ◽  
Mechanical Loads ◽  
Free Solder

The use of BGA (Ball Grid Array) interconnects utilizing the lead-free solder joint has grown rapidly because of its small volume and diversity of application. Thus, it requires the continuous quantification and refinement of lead-free solder joint reliability. The lead-free solder creep and cyclically applied mechanical loads cause metal fatigue on the lead-free solder joint which inevitably leads to an electrical discontinuity. In the field application, BGA solder joints experience mechanical loads during temperature changes caused by power up/down events as the result of the CTE (Coefficient of Thermal Expansion) mismatch between the substrate and the Si die. In this paper, extremely small resistance changes at joint area corresponding to through-cracks generated by thermal fatigue were measured. In this way, the failure was defined in terms of anomalous changes in electrical resistance of the joint. Furthermore the reliability of BGA solder joints in thermal cycling is evaluated by using the modified coffin-Manson criterion which may define and distinguish failure. Any change in circuit resistance according to the accumulated damage induced by the thermal cycling in the joint was recorded and evaluated in order to quantitate reliability of solder joint.

Methodology for Analyzing Slip Behavior in Ball Grid Array Lead-Free Solder Joints After Simple Shear

2009 ◽  
Vol 38 (12) ◽  
pp. 2702-2711 ◽  
Author(s):  
Bite Zhou ◽  
Thomas R. Bieler ◽  
Tae-Kyu Lee ◽  
Kuo-Chuan Liu
Keyword(s):  
Simple Shear ◽  
Solder Joints ◽  
Ball Grid Array ◽  
Lead Free ◽  
Lead Free Solder ◽  
Free Solder
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