TY - GEN
T1 - Activation Energy for Solder Bond Degradation
T2 - 46th IEEE Photovoltaic Specialists Conference, PVSC 2019
AU - Gopalakrishna, Hamsini
AU - Sinha, Archana
AU - Jordan, DIrk
AU - Tamizhmani, Govindasamy
N1 - Funding Information:
The funding support of Department of Energy, as a part of the PREDICTS 2 program (project DE-EE0007138) under SunShot initiative, is sincerely appreciated.
Publisher Copyright:
© 2019 IEEE.
PY - 2019/6
Y1 - 2019/6
N2 - The reliability of solder joints in the solar cell metallization-interconnect system influences the lifetime of photovoltaic modules. Two field-aged modules - one with Sn62Pb36Ag2 solder at the solder joints (Solarex MSX 60), and the other with the standard Sn60Pb40 solder (Siemens M55) - were subjected to a modified thermal cycling (TC) test of IEC 61215. Three sections in each module were maintained at 85°C, 95°C, and 105°C during the 15-minute high temperature dwell time. Current equivalent to the module short-circuit current was injected through the module when the chamber temperature was above 25°C to simulate regular field operation. This novel approach aims to induce thermomechanical fatigue (TMF) at the solder joints and intermetallic compound (IMC) formation at the metal/solder interfaces. The activation energy (Ea) for solder bond degradation was calculated based on the series resistance (Rs) increase in TC testing rather than power drop to avoid the effect of confounding variables. Module-level Rs increase in MSX 60 module after TC800 cycles and in M55 module after TC400 cycles was 1.22% and 183.7%, respectively. The Ea determined for the module with 2wt% Ag is 0.24 eV and for that with the standard solder is 0.27 eV. The solder bond degradation seems to have been driven by TMF rather than IMC formation for both modules.
AB - The reliability of solder joints in the solar cell metallization-interconnect system influences the lifetime of photovoltaic modules. Two field-aged modules - one with Sn62Pb36Ag2 solder at the solder joints (Solarex MSX 60), and the other with the standard Sn60Pb40 solder (Siemens M55) - were subjected to a modified thermal cycling (TC) test of IEC 61215. Three sections in each module were maintained at 85°C, 95°C, and 105°C during the 15-minute high temperature dwell time. Current equivalent to the module short-circuit current was injected through the module when the chamber temperature was above 25°C to simulate regular field operation. This novel approach aims to induce thermomechanical fatigue (TMF) at the solder joints and intermetallic compound (IMC) formation at the metal/solder interfaces. The activation energy (Ea) for solder bond degradation was calculated based on the series resistance (Rs) increase in TC testing rather than power drop to avoid the effect of confounding variables. Module-level Rs increase in MSX 60 module after TC800 cycles and in M55 module after TC400 cycles was 1.22% and 183.7%, respectively. The Ea determined for the module with 2wt% Ag is 0.24 eV and for that with the standard solder is 0.27 eV. The solder bond degradation seems to have been driven by TMF rather than IMC formation for both modules.
KW - PV module
KW - activation energy
KW - field-aged
KW - series resistance
KW - solder bond degradation
KW - thermal cycling
UR - http://www.scopus.com/inward/record.url?scp=85081535440&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85081535440&partnerID=8YFLogxK
U2 - 10.1109/PVSC40753.2019.8980754
DO - 10.1109/PVSC40753.2019.8980754
M3 - Conference contribution
AN - SCOPUS:85081535440
T3 - Conference Record of the IEEE Photovoltaic Specialists Conference
SP - 1955
EP - 1960
BT - 2019 IEEE 46th Photovoltaic Specialists Conference, PVSC 2019
PB - Institute of Electrical and Electronics Engineers Inc.
Y2 - 16 June 2019 through 21 June 2019
ER -