InAs Nanowire-Based Twin Electrical Sensors Enabling Simultaneous Gas Detection

Year: 2025

Authors: Baratto C., Musaev E., Demontis V., Luin S., Zannier V., Sorba L., Faglia G., Rovati L., Rossella F.

Autors Affiliation: CNR INO PRISM Lab, I-25123 Brescia, Italy; Univ Modena & Reggio Emilia, Dipartimento Sci Fis Informat & Matemat, I-41125 Modena, Italy; Univ Brescia, Dept Informat Engn, I-25123 Brescia, Italy; Univ Cagliari, Dept Phys, I-09042 Monserrato, Italy; Scuola Normale Super Pisa, NEST Lab, I-56127 Pisa, Italy; CNR, Inst Nanosci, I-56127 Pisa, Italy; Univ Modena & Reggio Emilia, Dept Engn Enzo Ferrari, I-41125 Modena, Italy.

Abstract: Epitaxially grown InAs NWs are relevant for electrical sensing applications due to the Fermi level pinning at the NW surface and are highly sensitive to the surrounding environment. While a single NW growth batch consists of millions of virtually identical replicas of the same NW, real samples display subtle differences in NW size, shape, and structure, which may affect detection performance. Here, electrical gas detection is investigated in two nominally identical or twin devices fabricated starting from the same NW growth batch. Two individual wurtzite InAs NWs are placed onto a fabrication substrate at a 2 mu m distance with a 90 degrees relative orientation, each NW is electrically contacted, and the nanodevices are exposed to humidity and NO2 flux diluted in synthetic air. Electrical signal versus time is measured simultaneously in each nanodevice upon exposure to different gases and concentrations. The observed detection limit is 2 ppm for NO2 and 20% for relative humidity. Correlation analysis methods are exploited by calculating autocorrelation and cross-correlation functions for the experimental signal pairs, indicating lack of cross-correlation in the signal noise of the two nanodevices, suggesting that signal differences between the twins could be ascribed mainly to nonidealities in the fabrication protocol and nanoscopic differences in the two nanostructures, rather than to different environmental conditions. While InAs nanowires are used here as demonstrators of simultaneous gas sensing, the approach is general and virtually applies to any nanoscale material suitable for the realization of two-terminal electronic devices.

Journal/Review: ACS APPLIED NANO MATERIALS

More Information: CB and EM acknowledge the support from Antares Vis ion; CB and GF acknowledge the support from the European Union Next Generation EU M4C2 1.1 under Grant PRIN 2022JZAA9WSENSEPLANET. LR and FR acknowledge the support from the National Recovery and Resilience Plan (PNRR), Mission 04, Component 2, Investment 1.5 NextGenerationEU, Call for tender No. 3277 dated December 30, 2021 (Award Number: 0001052 dated June 23, 2022). VD acknowledges the support from the Project ’’ Network 4 Energy Sustainable TransitionNEST ’’, Spoke 1, Project code PE0000021, funded by the European Union NextGenerationEU under the National Recovery and Resilience Plan (NRRP), Mission 4, Component 2, Investment 1.3, Call for tender No. 1561 of 11.10.2022, from the MUR.
KeyWords: InAs nanowires; gas detection; nanosensors; signal fluctuations; electrical transport
DOI: 10.1021/acsanm.4c07238