The elastic moduli of oriented tin oxide nanowires

Abstract

Tin oxide nanowires (NWs) exhibit interesting electronic properties, which can be harnessed for applications in nanoelectronic devices and sensors. Oriented single crystalline tin oxide NWs were grown at 45 degrees from a titanium dioxide substrate. Their elastic properties were investigated in a two-point geometry using an atomic force microscope (AFM) coupled with a scanning electron microscope under ultrahigh vacuum conditions. Young's modulus was calculated by bending individual NWs and measuring the force exerted on the AFM tip during force-displacement measurements. For the NWs investigated, having radial dimensions below 45 nm and length up to 1.2 mu m, we found an average value of 100 +/- 20 GPa, which is below the theoretical predictions calculated for different SnO₂ single crystal orientations, yet consistent with the indentation moduli of nanobelts. Finally, we discuss the effects of the nanowire-cantilever configuration on the measured Young's modulus.