TY - JOUR
T1 - Microstructure, isothermal and thermomechanical fatigue behaviour of leaded and lead-free solder joints
AU - Ghaleeh, Mohammad
AU - Baroutaji, Ahmad
AU - Al Qubeissi, Mansour
PY - 2020/11
Y1 - 2020/11
N2 - The reliability of solder joints is a critical issue in the microelectronics industry. The requirement of permanent electrical and thermal connections between solder alloys and the various components of a surface mount device is dependent upon the mechanical integrity of the solder and its interfaces. Accordingly, in this paper, the reliability of lead-free, Sn-3.8Ag-0.7Cu, and leaded, Sn-37Pb, solder alloys was investigated under both thermal-mechanical fatigue (TMF) and isothermal mechanical fatigue (IF) conditions. The investigation included material characterisation and fatigue testing on 4-ball grid array (BGA) specimens. The IF tests were carried out under load control at three different temperatures including Room Temperature (RT), 35 °C and 75 °C. Also, a set of ‘not-in-phase’ (nIP), ‘in-phase’ (IP) and ‘out-of-phase’ (OoP) combined thermal and mechanical cycling tests were carried out to investigate the TMF behaviour of the solders. The stress-life curves for each test condition were generated and then compared taking into account the observations on microstructure. It was found that the IF and TMF performance of Sn-3.8Ag-0.7Cu alloy was better than Sn-37Pb alloy when expressed as stress-life curves. Additionally, the Sn-3.8Ag-0.7Cu was less susceptible to the changes in temperature. This study provides a comprehensive insight into the reliability of solder alloys under a wide range of loading conditions.
AB - The reliability of solder joints is a critical issue in the microelectronics industry. The requirement of permanent electrical and thermal connections between solder alloys and the various components of a surface mount device is dependent upon the mechanical integrity of the solder and its interfaces. Accordingly, in this paper, the reliability of lead-free, Sn-3.8Ag-0.7Cu, and leaded, Sn-37Pb, solder alloys was investigated under both thermal-mechanical fatigue (TMF) and isothermal mechanical fatigue (IF) conditions. The investigation included material characterisation and fatigue testing on 4-ball grid array (BGA) specimens. The IF tests were carried out under load control at three different temperatures including Room Temperature (RT), 35 °C and 75 °C. Also, a set of ‘not-in-phase’ (nIP), ‘in-phase’ (IP) and ‘out-of-phase’ (OoP) combined thermal and mechanical cycling tests were carried out to investigate the TMF behaviour of the solders. The stress-life curves for each test condition were generated and then compared taking into account the observations on microstructure. It was found that the IF and TMF performance of Sn-3.8Ag-0.7Cu alloy was better than Sn-37Pb alloy when expressed as stress-life curves. Additionally, the Sn-3.8Ag-0.7Cu was less susceptible to the changes in temperature. This study provides a comprehensive insight into the reliability of solder alloys under a wide range of loading conditions.
KW - Ball grid array
KW - Isothermal fatigue
KW - Lead-free
KW - Shear stress
KW - Solder joints
KW - Thermo-mechanical fatigue
UR - http://www.scopus.com/inward/record.url?scp=85089529495&partnerID=8YFLogxK
UR - https://www.sciencedirect.com/science/article/pii/S1350630720310566?via%3Dihub
U2 - 10.1016/j.engfailanal.2020.104846
DO - 10.1016/j.engfailanal.2020.104846
M3 - Article
AN - SCOPUS:85089529495
SN - 1350-6307
VL - 117
JO - Engineering Failure Analysis
JF - Engineering Failure Analysis
M1 - 104846
ER -