Different Nanowire Materials Localized Growth and In-Situ Integration for Electronic Nose Applications

Nanowires of different materials have been grown site-selectively and integrated in one single chip using a new methodology. The chemical vapor deposition approach performed to grow these nanowire-based devices can be easily tuned, representing a simple, fast and adjustable fabrication process for the direct integration of nanowire meshes in multifunctional devices. This proof-of-concept study focuses on the deposition of SnO2, WO3 and Ge nanowires on the same chip. The prepared sensors have been tested under varying concentrations of CO, NO2and humidity diluted in synthetic air, exhibiting satisfactory gas sensing responses. A principal component analysis has been performed with the collected data and responses towards different gases can be easily classified in clusters. Therefore, the devices here presented are suitable for environmental monitoring.