Electromigration Behavior of Ionized Cluster Beam Deposited Aluminum Films on SiO2

摘要

One of the most important features of thin-film metallization in microelectronic devices is its resistance (or lack of resistance) to damage due to electromigration. This is known to become increasingly important as the size of the interconnections becomes smaller. It is thus of utmost importance to look for materials or deposition methods which are capable of improving the presently obtained electromigration resistance. One of the parameters which allows an immediate assessment of the time under dc stressing until failure has occurred is the activation energy Q for electromigration which appears in the exponential term of the frequently used Black equation. The deposition method described in this letter seems to substantially increase the activation energy for electromigration of pure A1 films. This appears to be of considerable interest since the electronics industry tends to prefer the continuing usage of aluminum as a base metal without the necessity to switch to other materials. Reprints. (jes)