Experimental evaluation of ZnO nanowire array based dynamic pressure sensor

This paper presents the synthesis of ZnO nanowire array on metallic alloy substrate, its packaging and experimental evaluation for dynamic pressure sensing applications. Vertically aligned dense nanowire array was synthesized using hydrothermal method. Crystal structure, morphology and chemical composition analysis were carried out using X-ray diffraction, field emission scanning electron microscopy and energy dispersive spectroscopy respectively. ZnO nanowires were grown to an average height of 2.2 µm with an average diameter of 200 nm. The as-synthesised nanowire array was packaged as a pressure sensor and was evaluated for its sensing properties. The sensor responded to shock pressure input with a sensitivity 1.65 ± 0.15 mV/bar, rise time 1.38 ms and discharge time 1.79 ms. ZnO nanowire array demonstrated highly promising features which are desirable for a dynamic pressure sensor.