Plastic deformation study of vertical Zinc oxide nanowires for polymer cantilever based sensor applications

Abstract

In this letter, the mechanical properties of piezoelectric ZnO nanowire (NW) films have been measured using a nanoindentation technique. We demonstrated a fabrication process to embed this NW film inside a polymeric (SU-8) cantilever. Mechanical properties of this SU-8/ZnO NW film and cantilever have been measured. The ZnO NWs have been grown vertically using a low-temperature chemical synthesis. The observed value of Young's modulus for ZnO NW is in the range 72-93 GPa. After embedding this NW film inside a polymer matrix, the Young's modulus value was reduced to the range 5-19 GPa. The mechanical behavior of the NW-embedded cantilever has also been investigated using the nanoindentation technique. These cantilevers have been shown to be suitable for surface stress-sensing applications.