Reliability of dielectric barriers in copper damascene applications

The film properties of two PECVD deposited dielectric copper barrier films have been optimized to improve BEOL device reliability in terms of electromigration. Two critical aspects that affect electromigration are the dielectric barrier film hermeticity and adhesion to copper. We use a method to quantify the barrier film hermeticity of the BLO/spl kappa/ I low-/spl kappa/ dielectric film to be similar to that of silicon nitride. In addition, the interfaces between damascene nitride with copper, as well as BLO/spl kappa/ I with copper have been engineered to improve the interfacial adhesion energy to >10 J/m/sup 2/ for both damascene nitride and BLO/spl kappa/ I.