Authors: V.R. Tirumala, C.M. Stafford, R. Huang, E.K. Lin and L.E. Ocola
Affilation: National Institute of Standards and Technology, United States
Pages: 516 - 517
Keywords: hydrogels, e-beam lithography
The mechanical stability of polymer nanolines is crucial to the success of semiconductor device fabrication. Recent experimental and modeling studies have focused on the influence of processing conditions on the stability of densely patterned lines. However, insights into the deformation behavior of individual nanosized polymer lines is lacking so far. Here, we show that hydrogels, which respond to an environmental stimulus with a change in their size, can be used as model materials to study the failure modes of nanopatterned polymers. A direct-write electron beam lithography process was recently developed to nanofabricate poly (N-isopropylacrylamide), a well known thermoresponsive polymer. The buckling modes of nanopatterned polymers are studied by subjecting the nanopatterned hydrogels to a stimulus-induced swelling pressure. Our results confirm the sub-Rayleigh phonon propagation modes observed in nanoimprinted polymer lines. We present the effect of size and shape of nanopatterned polymers on their failure modes. A three-dimensional Euler buckling model is developed to explain the results.