Title :
CVD Co capping layers for Cu/low-k interconnects: Cu EM enhancement vs. Co thickness
Author :
Yang, C. -C ; Baumann, F. ; Wang, P.-C. ; Lee, SY ; Ma, P. ; AuBuchon, J. ; Edelstein, D.
Author_Institution :
IBM Res., Albany, NY, USA
Abstract :
Co films with various thicknesses were selectively deposited as Cu capping layers by chemical vapor deposition technique. Selectivity of the Co deposition between Cu and dielectric surfaces was improved by both raising the deposition pressure and adopting a pre-clean process prior to the Co deposition. Degree of electromigration resistance enhancement was observed to be dependent on the deposited Co thickness. Compared to the no-Co control, significant EM lifetime enhancement was observed when the Co cap is thicker than 6nm.
Keywords :
chemical vapour deposition; cobalt; copper; electromigration; integrated circuit interconnections; CVD capping layer; Co; Cu; EM enhancement; chemical vapor deposition technique; deposition pressure; dielectric surfaces; electromigration resistance enhancement; low-k interconnects; Copper; Dielectrics; Process control; Resistance; Surface treatment; Thickness measurement;
Conference_Titel :
Interconnect Technology Conference and 2011 Materials for Advanced Metallization (IITC/MAM), 2011 IEEE International
Conference_Location :
Dresden
Print_ISBN :
978-1-4577-0503-8
DOI :
10.1109/IITC.2011.5940289