Intrinsic instability of electromigration induced mass transport in a two-dimensional conductor

✍ Scribed by C.Q Ru

• Publisher: Elsevier Science
• Year: 1999
• Tongue: English
• Weight: 164 KB
• Volume: 47
• Category: Article
• ISSN: 1359-6454
• DOI: 10.1016/s1359-6454(99)00241-4

✦ Synopsis

AbstractÐThe instability of electromigration induced mass transport within a thin-®lm conductor and its relation to catastrophic growth of voids in the later stage of electromigration failure are studied. To isolate intrinsic instability of mass transport from extrinsic defects, a void-free homogeneous conductor is examined in which surface and interface diusion are neglected. Explicit conditions are derived for linearized instability and the eects of various diusion mechanisms on instability are identi®ed. It is found that thermomigration and electromigration provide the major driving forces for linear instability of uniform mass transport. In particular, thermomigration plays the dominant role in the onset of linear instability. The parameters which govern the onset of linear instability are the current density and temperature of the conductor. Linear instability can occur when Joule heating due to current crowding leads to suciently high temperature rise. The results appear to provide new insight into the understanding of some experiments where catastrophic void growth was observed in the later stage of electromigration failure when the amount of mass loss and temperature rise were suciently high.