Soft lithography uses a patterned elastomer polydimethylsiloxane (PDMS) as the stamp or mold to generate micro- and nano-patterns. This method is limited for features smaller than 100 nm, as the low modulus PDMS may deform and result in pattern collapse and rounded corners.
Penn scientists have developed a novel method to form sub-100nm features on nano-patterned thin films of PDMS that takes advantage of the ability of PDMS to be distorted by solvents, mechanical forces, and heat in a controlled and predictable fashion.
Issued US patent(s): 8,530,689
Y. Zhang et al., Nano Letters, 8, 1192 (2008)