Transparent film sensor for strain measurement using carbon nanotube networks
W.-S. Chang, S.-A. Song, J.-H. Kim, J.-W. Kim, H.-C. Lee, C.S. Han
Korea Institute of Machinery and Materials, KR
Keywords: SWCNT film, Strain sensor, Spray deposition, Electromechanical properties, Gage factor
Abstract:Since the carbon nanotube was reported by Iiijima, it has been intensively studied due to their great potential in nanoelectronics and nanomechanical devices. Recently, experimental results show that sing-wall carbon nanotubes (SWCNTs) change their electronic properties when subjected to strain. In this study, the strain sensing characteristics of SWCNTs networks were investigated to develop a transparent film sensor for strain sensing. The SWCNTs film are formed on flexible substrates of poly(ethylene terephthalate) (PET) using spray process. In this manner we could control the transparency and obtain excellent uniformity of the networked SWCNT film. The carbon nanotube film is isotropic due to randomly oriented bundles of SWCNTs. Using experimental results it is shown that there is a nearly linear change in resistance across the film when it is subjected to tensile stress. The results presented in this study indicate the potential of such films for high sensitive transparent strain sensors on macro scale.