© 2005 CSL

Introduction: Cathode voiding and drifting.

Electromigration causes depletion or accumulation of metal atoms at the locations where the imbalance of atom fluxes occurs.

Over time this net flux of atoms will cause voiding and extrusion in the line which in turn can cause failure of the interconnect.

This experimental setup (Figure on the left hand side) clearly demonstrates voiding at the cathode followed by drifting.

*Liniger et al. (2002).  Voiding at the end of a  2 µm wide line exposed to  a current density of 18  µA/mm^2 at :

a) 5hr  b) 8hr,  c) 10hr,  d) 12hr.


Much like the bodies central nervous system, this thin film network (interconnect network) in an integrated circuit serves as the link between the circuit elements to conduct electric current. This underlines the technological importance of interconnect structures, whose failure simply means the failure of the circuit.

* Cathode failure in Intel's 0.25 µm technology used in Celeron™ and Pentium® II microprocessors.