Influence of N2O plasma treatment on PET-based flexible bending sensors with ZnO nanorod array cross-linked with interdigitated electrode structures

Abstract

We present a highly sensitive bending sensor fabricated with hydrothermally grown zinc oxide nanorod (NR) arrays cross-linked with interdigitated electrode patterns on polyethylene terephthalate substrates. To examine the effects of microstructural change in NR arrays on the device characteristics, N2O plasma treatment (PT) was carried out for 3 and 6 min for the seed layers. Negative resistance change (Delta R) was obtained in the case of convex bending, while positive Delta R was measured under the concave bending from every device prepared under different PT conditions, which is due to the change in the number of cross-linkings between the NRs. The device with no PT condition showed the highest gauge factor of 196 at a bending strain of 1.75% in the convex direction.