Thin film patterning by surface-plasmon-induced thermocapillarity

It is reported that standing surface-plasmon-polariton (SPP) waves can cause regular thickness undulations of thin polymethyl methacrylate (PMMA) films above a metallic substrate. Ripples, rings, and hillock arrays with long-range order were found. Numerical calculations reveal that periodic in-plane temperature profiles are generated in the PMMA due to the nonradiative damping of SPP interference patterns. Computer simulations on the temperature-gradient-driven mass transport confirm that thermocapillarity is the dominating mechanism of the observed surface patterning. (c) 2007 American Institute of Physics.