Impact of molecular mobility on the tribological properties of nanoscale devices

COLL 354

Scott E. Sills1, Jane Frommer2, and René M. Overney1. (1) Department of Chemical Engineering, University of Washington, Benson Hall, Box 351750, Seattle, WA 98195, (2) IBM Almaden Research Center, 650 Harry Road, San Jose, CA 95120
Molecular mobility is increasingly important in technologies that use nanoscopically confined materials. For instance, the thermo-mechanical process of terabit data storage in ultrathin polymer films demands basic knowledge of the relationship between molecular mobility and the resulting tribo-rheological properties. Insight into these relationships is furnished through scanning force microscopy (SFM) studies of model polymer systems. Frictional dissipation mechanisms will be discussed in the context of creeping friction dynamics and activated relaxation processes, i.e. mobility potential barriers. The effect of dimensional constraints on molecular mobility will be examined, and spatially heterogeneous mobilities will be explored with glass transition profiles. Methods for engineering molecular mobilities for prescribed tribological conditions will be emphasized for the design of polymer based nano-devices.