Electromigration Behavior of Aluminum Films Deposited on Silicon by Ionized Cluster Beam and Other Techniques

摘要

It has been briefly mentioned in the literature that aluminum films which have been deposited on pure silicon by the ionized cluster beam (ICB) technique have a remarkably high resistance against electromigration damage. In other words, these films appear to be less vulnerable to the formation of voids (opens) when a direct current of high density is passed through them. No details have been published so far. However, information on this observation is considered to be potentially important for the electronics industry which has been troubled since the beginning of large scale integration with electromigration-caused failures in thin-film metallizations. Electromigration experiments have been carried out on aluminum thin films which have been deposited on oxide-free silicon by employing the ionized cluster beam technique as well as other related deposition methods. It has been found that the same high electromigration resistance and film structure is obtained with or without utilizing a nozzled crucible and with or without applying ionization and acceleration voltages during deposition. The conclusions are supported by electromigration lifetime measurements, scanning electron micrographs, optical micrographs, reflective high-energy electron diffraction, and x-ray diffraction. Keywords: Thin films; Microelectronics; Reprints. (kt)