Admin Login • Instructor Login • Student Login

Physics and Astronomy

Your Support

Departmental Colloquium

ThermoChemical NanoLithography (TCNL)  
Guest Speaker
Prof. Elisa Riedo  
Guest Affiliation
School of Physics, Georgia Institute of Technology  
Thursday, September 27, 2012 4:00 pm - 5:00 pm  

Nanolithography has been recognized as an essential component of future technologies. However, many of the techniques employed today still have significant limitations in terms of resolution, speed of writing, and the chemical diversity of the materials that can be patterned on an arbitrary substrate. Achieving chemical patterning at resolutions of 100 nm and below has been a challenge because of the difficulty in spatially confining reactions and because of the need to control the interactions of the reactant and products with the substrates and stamps. Over the past few years, by using resistively-heated atomic force microscopy (AFM) tips, the ability to thermally activate a chemical reaction at the nm scale at the surface of a material has been demonstrated in our group. Local chemical changes with feature sizes down to 12 nm at scan speeds up to 1 mm/s have been obtained with this new technique, commonly referred to as ThermoChemical NanoLithography (TCNL). In this seminar I will review recent research on TCNL, which includes: i) acid and amine patterning on the surface of copolymers containing thermally labile groups, and subsequent functionalization with proteins and DNA, ii) nanofabricating poly(p-phenylene vinylene) (PPV) nanowires, a typical electroluminescence conjugated polymer, with a clear “turn-on” of luminescence, iii) producing reduced graphene oxide (r-GO) structures by local thermal reduction of insulating GO with a 104 increase in conductivity for features sizes as small as 12 nm, iv) crystallization of Pb(Zr0.52Ti0.48)O3 and PbTiO3 ferro/piezoelectric nanostructures on a variety of substrates including plastic, achieving lines with widths ≥ 30 nm, spheres with diameter  10 nm and densities up to 213 Gb/in2, and v) producing density gradients of functional groups on polymer surfaces with nanoscopic resolution.