TY - GEN
T1 - Measurement of temperature distribution in SnAg3.5 flip-chip solder joints during current stressing using infrared microscopy
AU - Hsiao, Hsiang Yao
AU - Chen, Chih
PY - 2008/12/1
Y1 - 2008/12/1
N2 - Several simulation studies reported that a hot spot exists in flip-chip solder bumps under accelerated electromigration. Yet, there are no experimental data to verify it. In this paper, the temperature distribution during electromigration in flip-chip SnAg3.5 solder bumps is directly inspected using infrared microscopy. Two clear hot spots are observed in the bump. One is located at the region with peak current density, and the other one is at the bump edge under the current-feeding metallization on the chip side. Under a current stress of 1.06 × 104 A/cm2, the temperature in the two hot spots are 161.7 °C and 167.8 °C, respectively, which surpass the average bump temperature of 150.5 °C. In addition, effect of under-bump-metallization (UBM) thickness on the hot spots is also examined. It indicates that the hot-spot temperature in the solder bump increases for the solder joints with a thinner UBM. Electromigration test indicates that these hot spots have significant influence on the initial failure location.
AB - Several simulation studies reported that a hot spot exists in flip-chip solder bumps under accelerated electromigration. Yet, there are no experimental data to verify it. In this paper, the temperature distribution during electromigration in flip-chip SnAg3.5 solder bumps is directly inspected using infrared microscopy. Two clear hot spots are observed in the bump. One is located at the region with peak current density, and the other one is at the bump edge under the current-feeding metallization on the chip side. Under a current stress of 1.06 × 104 A/cm2, the temperature in the two hot spots are 161.7 °C and 167.8 °C, respectively, which surpass the average bump temperature of 150.5 °C. In addition, effect of under-bump-metallization (UBM) thickness on the hot spots is also examined. It indicates that the hot-spot temperature in the solder bump increases for the solder joints with a thinner UBM. Electromigration test indicates that these hot spots have significant influence on the initial failure location.
UR - http://www.scopus.com/inward/record.url?scp=63049113048&partnerID=8YFLogxK
U2 - 10.1109/EPTC.2008.4763505
DO - 10.1109/EPTC.2008.4763505
M3 - Conference contribution
AN - SCOPUS:63049113048
SN - 9781424421183
T3 - 10th Electronics Packaging Technology Conference, EPTC 2008
SP - 639
EP - 643
BT - 10th Electronics Packaging Technology Conference, EPTC 2008
Y2 - 9 December 2008 through 12 December 2008
ER -