Light-Induced Nanostructure Formation using Azobenzene Polymers
Yager, K.G.; Barrett, C.J. "Light-Induced Nanostructure Formation using Azobenzene Polymers" Polymeric Nanostructures and their Applications, Nalwa, H.S., ed.
American Scientific Publishers 2006
, Chapter 8
We review the field of azo-polymers; in particular focusing on their photo-responsive motion and use for nano-patterning.
The formation of useful nanostructures, and interfacing these with macro-world devices, is an ongoing research challenge. The microelectronics industry has a wide variety of optical tools available for patterning using light and has achieved remarkable control over material properties. It is therefore attractive to investigate future patterning techniques that take advantage of this visible-light lithographic infrastructure. Azobenzene molecules exhibit numerous photoresponsive properties, which can be exploited to locally modify material properties. Specifically, irradiation of azobenzenes with light causes a fast and efficient change of the molecule’s configuration. This photoisomerization can be exploited as a photoswitch, to orient the chromophore (which induces birefringence) or even to perform all-optical surface topography patterning. These photo-motions enable many interesting applications, ranging from optical components and lithography to sensors and smart materials. This chapter will discuss the many unique properties of the azobenzene chromophore and the exceptional material control enabled when these chromophores are incorporated in a polymeric matrix. More specifically, we will attempt to highlight the ways in which azo-polymers could be used as tools in the emerging field of controlled nanostructure formation.