3D microfabrication of single-wall carbon nanotube/polymer composites by two-photon polymerization lithography

We present a method to develop single-wall carbon nanotube (SWCNT)/polymer composites into arbitrary three-dimensional micro/nano structures. Our approach, based on two-photon polymerization lithography, allows one to fabricate three-dimensional SWCNT/polymer composites with a minimum spatial resolution of a few hundreds nm. A near-infrared femtosecond pulsed laser beam was focused onto a SWCNT-dispersed photo resin, and the laser light solidified a nanometric volume of the resin. The focus spot was three-dimensionally scanned, resulting in the fabrication of arbitrary shapes of SWCNT/polymer composites. SWCNTs were uniformly distributed throughout the whole structures, even in a few hundreds nm thick nanowires. Furthermore, we also found an intriguing phenomenon that SWCNTs were self-aligned in polymer nanostructures, promising improvements in mechanical and electrical properties. Our method has great potential to open up a wide range of applications such as micro- and nanoelectromechanical systems, micro/nano actuators, sensors, and photonics devices based on CNTs.