Electromigration characteristics of TiN barrier layer material

Electromigration reliability of TiN barrier layer itself has been studied. Our results show no electrically measurable electromigration. Resistance increase and open failure under high density current stress are apparently due to a purely thermally activated process with an activation energy of 1.5 eV. TiN resistance is projected to be stable for 10 years if the temperature of the hottest spot in TiN is kept below 408/spl deg/C, which together with electrical sheet resistance and thermal resistance determine the acceptable current density in TiN.