Nanowriting with conducting polymers

Molecularly ordered nanoscale patterns of conducting polymers can be prepared with high precision by using a scanning probe method, a new study reports (J. Am. Chem. Soc. 2006, 128, 6774). Scientists at the Naval Research Laboratory, Washington, D.C., and Georgia Institute of Technology developed a procedure in which a solid "ink"-—poly(3-dodecylthiophene) in this study-—is applied to a customized atomic force microscope cantilever that's equipped with a fast-acting tip heater. Referred to as thermal dip pen nanolithography, the method was used to pattern a silica surface with polymer structures measuring less than 100 nm in width and ranging in thickness (height) from a single monolayer (shown) to tens of monolayers. On the basis of single- and multilayered pattern thicknesses, the team concludes that the polymer structures are ordered with the alkyl groups perpendicular to the surface, an orientation that favors charge-carrier mobility.