Patterned Polymer Nanowire Arrays

Arrays of polymer nanowires can be fabricated on a large scale from various types of polymers by using a process that combines laser interference patterning and inductively coupled plasma etching, according to a U.S.-Chinese research team (ACS Nano, DOI: 10.1021/nn103319p). Numerous methods are available for preparing arrays of semiconductor and other types of inorganic nanowires. But few techniques have been demonstrated for making organic or polymeric nanowires, and even fewer methods have been developed for preparing these materials as patterned arrays. Developing new ways of making such arrays could lead to advances in the fields of organic light-emitting diodes and solar cells. Zhong Lin Wang and Hao Fang of Georgia Institute of Technology and coworkers there and at Peking University exposed polymer films to interference patterns formed by crossing a pair of laser beams. The process, which was applied separately to UV-absorbent and non-UV-absorbent films, generated ablation trenches with patterns and dimensions that could be controlled by tuning the laser parameters and by rotating and reexposing the films. The team then etched the patterned films, leaving behind arrays of polymer nanowires with spacings ranging from nanometers to micrometers.