Title :
Measurement of temperature distribution in SnAg3.5 flip-chip solder joints during current stressing using infrared microscopy
Author :
Hsiao, Hsiang-Yao ; Chen, Chih
Author_Institution :
Dept. of Mater. Sci. & Eng., Nat. Chiao Tung Univ., Hsinchu
Abstract :
In this paper, the temperature distribution during electromigration in flip-chip SnAg3.5 solder bumps is directly examined 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 times 104 A/cm2, the temperature in the two hot spots are 161.7degC and 167.8degC, respectively, which surpass the average bump temperature of 150.5degC. 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.
Keywords :
electromigration; flip-chip devices; integrated circuit testing; materials testing; silver alloys; solders; temperature distribution; thermal management (packaging); tin alloys; Sn-Ag; SnAg3.5 flip-chip solder joints; current density; current stressing; current-feeding metallization; electromigration; hot spots; infrared microscopy; temperature distribution; Current density; Current measurement; Electromigration; Flip chip solder joints; Metallization; Microscopy; Soldering; Stress measurement; Temperature distribution; Temperature measurement;
Conference_Titel :
Electronic Materials and Packaging, 2008. EMAP 2008. International Conference on
Conference_Location :
Taipei
Print_ISBN :
978-1-4244-3620-0
Electronic_ISBN :
978-1-4244-3621-7
DOI :
10.1109/EMAP.2008.4784283
