Title :
Fracture mechanics life prediction for microscale components, with application to wire bonding
Author :
Harris, D.O. ; Sire, R.A. ; Popelar, C.F. ; Kanninen, M.F. ; Davidson, D.L. ; Duncan, L.B. ; Kallis, J.M. ; Buechler, D.W. ; Backes, P.G. ; Reizman, F.
Author_Institution :
Failure Anal. Associates Inc., Menlo Park, CA, USA
Abstract :
Experimental and analytical results on the lifetime of 25 mu m diameter aluminum 1% silicon wire bonds subject to on/off current cycling are presented, along with related scanning electron microscopy of the heel area of the bond. The analytical results utilize a steady-state temperature solution for the wire in conjunction with finite element stress analysis to provide inputs to fracture mechanics calculations of fatigue crack growth. These calculations utilize macroscopic material properties, but with a fatigue crack growth threshold of zero. Good agreement between experiments and prediction was obtained, with scatter in the observations accounted for by consideration of a reasonable range of initial crack sizes. The results indicate that fracture mechanics techniques utilizing macroscopic material properties are applicable to life prediction of microscale components.<>
Keywords :
aluminium alloys; fracture mechanics; lead bonding; life testing; scanning electron microscope examination of materials; silicon alloys; AlSi; crack sizes; fatigue crack growth; finite element stress analysis; fracture mechanics; heel area; life prediction; macroscopic material properties; microscale components; on/off current cycling; scanning electron microscopy; steady-state temperature solution; wire bonding; Aluminum; Fatigue; Finite element methods; Material properties; Scanning electron microscopy; Silicon; Steady-state; Stress; Temperature; Wire;
Conference_Titel :
Reliability Physics Symposium, 1991, 29th Annual Proceedings., International
Conference_Location :
Las Vegas, NV, USA
Print_ISBN :
0-87942-680-2
DOI :
10.1109/RELPHY.1991.145984
