Resistive Pressure Sensor with Carbon Nanotube Electrodes towards Flexible Electronics Applications

A. Palumbo, R. Zhang, K. Yan, S. Chen, G. Hader, J. Chang, E.H. Yang
Stevens Institute of Technology,
United States

Keywords: flexible electronics, pressure sensor, carbon nanotubes, PDMS


Flexible electronics has directed development and research of unique instrumentation and measurement techniques to achieve conformable sensors for a wide range of applications [1]. Conventional high-performance electronic materials such as silicon are not flexible, whereas many flexible materials, such as conducting polymers, are often characterized by poor electric properties [2]. Thus, high mobility materials in a flexible configuration are desirable, and carbon nanotubes (CNTs) are promising owing to their excellent electronic properties and flexibility owing to their small diameter. Here, we present a flexible and stretchable pressure sensor composed of vertically aligned CNTs (VACNTs) partially embedded in a polydimethylsiloxane (PDMS) substrate. VACNTs were grown via chemical vapor deposition and transferred onto PDMS as a stretchable electrode. Two such electrodes were placed face-to-face. Here, increased pressure is directly proportional to a detectable change in resistance, enabled by increased contact between the opposing electrode surfaces. The measured resistance was maintained at stretching up to 180%, with a rapid response time during loading and unloading. As a proof-of-concept, the sensor was successfully tested for measuring biological signals of a person. This work will directly impact the development of pressure sensing devices toward medical and e-skin applications. References [1] Wong, W. S. & Salleo, A. Flexible electronics: materials and applications. 11, (Springer Science & Business Media, 2009). [2] Nyholm, L., Nyström, G., Mihranyan, A. & Strømme, M. Adv. Mater. 23, 3751–3769 (2011).