Enhanced metalorganic chemical vapor deposition titanium nitride film fabricated using tetrakis-dimethylamino-titanium for barrier metal application in sub-half-micron technology

Abstract

Enhanced metalorganic chemical vapor deposition (MOCVD) titanium nitride (TiN:C) film with low resistivity (< 700 mu Omega . cm) has been fabricated by thermal decomposition of tetrakis-dimethylamino-titanium (TDMAT; Ti[N(CH3)(2)](4)) Enhancement is carried out by in-situ N-2 plasma treatment of as-deposited TiN:C film and the enhanced TiN:C film has good stability: less than 4% increase in film resistivity after exposure to air for 24 days. The amount of oxygen absorbed in this enhanced TiN:C film after air exposure, determined by Auger electron spectroscopy (AES) was significantly reduced. This enhanced MOCVD TiN:C film has been successfully applied to sub-half-micron devices. A void-tree tungsten plug (W plug) for sub-half-micron holes can be achieved. Good barrier performance and low contact/via resistance have also been demonstrated.