Highly flexible and biocompatible Carbon Nanotube thin film transistors

We demonstrate a highly flexible and biocompatible Single-Walled Carbon Nanotube (SWNT) based thin film transistor (TFT). These devices were fabricated on a parylene-C substrate (10¿m) and encapsulated from the environment with a 1¿m thick parylene-C layer. Carbon nanotube (CNT) TFT was realized by field assisted (dielectrophoretic) assembly followed by electrical breakdown of SWNTs at room temperature. These SWNT TFTs exhibited p-type behavior with a mobility of ~55cm²/Vs and an ON/OFF ratio of ~10³. The flexible SWNT transistors did not display any significant changes in their performance after repetitive bending tests. The ON current of the transistor deviated by only ±8.9% after sharp folding (R=1.5mm) conditions. The potential applications of parylene-C packaged flexible SWNT field effect transistors (FET) are numerous including disposable biosensors, wearable and implantable electronics and sensors.