AVS 50th International Symposium
    Surface Science Monday Sessions
       Session SS2-MoA

Paper SS2-MoA7
Evaluation of the Surface Characteristics and Mechanical Properties of Interconnect Films and their Correlation with CMP Process

Monday, November 3, 2003, 4:00 pm, Room 327

Session: Tribology, Adhesion, and Friction
Presenter: P.B. Zantye, University of South Florida
Authors: P.B. Zantye, University of South Florida
A.K. Sikder, University of South Florida
A. Kumar, University of South Florida
Correspondent: Click to Email
Chemical Mechanical Planarization (CMP) has emerged as one of the most widely used Back End of Line (BEOL) semiconductor manufacturing process for fabrication of present generation Cu interconnect structures. CMP is synergistic combination of tribological and chemical phenomena occurring at the surface of the polishing pad and wafer in presence of chemically active slurry. Thus, the frictional forces that act upon the wafer during CMP assume significant importance for effective characterization of the CMP process. In this research the surface characteristics and mechanical properties of various candidate materials Cu (wiring metal) and interlayer dielectrics (ILD) SiLK@super TM@ (soft polymer), and SiO@sub2@ (ceramic) have been evaluated. The surface roughness of the candidate materials was determined using the Atomic Force Microscopy (AFM) technique. The mechanical properties (Young's Modulus and Hardness) of Cu, SiLK@super TM@ and SiO@sub2@ were evaluated usi! ng MTS Nanoindentor@superTM@. The material removal behavior and dry friction characteristics were studied by micro scratch testing and the CMP process of materials under investigation was simulated on the Bench Top CMP tester. The coefficient of friction (COF) was monitored in situ during initial and final part of wafer coupon polishing. The surface characteristics, mechanical properties, dry friction and material removal were then correlated with the CMP process for each material to get an insight in to the polishing behavior of these candidate materials when planarized with different material specific slurries and polishing pads.