Effect of modified interfaces on electromigration of passivated Al lines
C E. Kalnas, J M. Phelps, T N. Marieh, A Ho
Al interconnect lines, 2.6 υm wide, 0.5 υm thick, and 300 υm long, were synthesized with modified metal/passivation interfaces. The interface modifications are discontinuous along the length of the line, enabling comparison of void formation in modified regions with unmodified regions. Lines were electromigraton tested at a current density of 2.75 x 106 A/cm2 and mean stress temperatures of 229.1degrees}C (which includes joule heating of 4.7 degrees}C) to resistance increases of 1.8 %, 4.3 % and 19.8 %. Perferential formation of voids in the modified regions was observed.