Embedding conductive patterns of elastomer nanocomposite with the assist of laser ablation

This work introduces a simple and low-cost microfabrication technique utilizing laser ablation to embed conductive elastomer nanocomposite within an insulating bulk elastomer. Nanocomposite consisting of poly(dimethylsiloxane) and a network of carbon nanotubes functions as apiezoresistive sensor material. Microstructures are embedded with the assist of laser ablation which utilizes a focused laser beam to ablate through a thin polymer film following apath programmed via software. This approach eliminates hardware such as photo-mask or stamp, which offers distinct advantages in reducing fabrication time and cost in prototyping of sensor devices. Various patterns of polymer film and embedded nanocomposite are demonstrated with spatial resolution down to 34 lm. To characterize patterning quality, different fabrication conditions are tested and uniformity (width, thickness) data are measured ith optical profiling. Sensor prototypes are demonstrated based on the piezoresistive response of nanocomposite under tensile strain. Strain sensors could detect large-range ([45%) tensile strain with sensing a factor of about 4, showing promising feasibility for various sensing applications. © 2011 Springer-Verlag