Intrinsic device-to-device variation in graphene field-effect transistors on a Si/SiO₂ substrate as a platform for discriminative gas sensing

Arrays of nearly identical graphene devices on Si/SiO₂ exhibit a substantial device-to-device variation, even in case of a high-quality chemical vapor deposition (CVD) or mechanically exfoliated graphene. We propose that such device-to-device variation could provide a platform for highly selective multisensor electronic olfactory systems. We fabricated a multielectrode array of CVD graphene devices on a Si/SiO₂ substrate and demonstrated that the diversity of these devices is sufficient to reliably discriminate different short-chain alcohols: methanol, ethanol, and isopropanol. The diversity of graphene devices on Si/SiO₂ could possibly be used to construct similar multisensor systems trained to recognize other analytes as well.