Electrowetting devices with transparent single-walled carbon nanotube electrodes

Microfluidic devices based on the electrowetting principle, more specifically electrowetting on dielectric, were fabricated using transparent single-walled carbon nanotube films as electrodes. The films were spray coated on glass and polyethylene terephalate substrates. The transmittance and sheet resistance remain unchanged after patterning the films using typical photolithography and plasma etching. Operation of water droplets over the patterned nanotube electrodes was demonstrated, and the performance was found to be comparable to that over the usual metal electrodes. The requirement of transparent electrodes is estimated for displays based on electrowetting machanism, and nanotube films indicate promise for such a type of devices.(c) 2007 American Institute of Physics.