Coulomb blockade tuned by NO2 molecules in nanostructured silicon

We have demonstrated that the electrochemical etching of heavily doped Si can be used as a simple self-assembly technique for the fabrication of Si nanocrystal arrays. The obtained nanostructures exhibit CB behavior at RT, and are very sensitive to the presence of molecules with high electron affinities, such as NO2. Thus, exploiting the tunability of the quantum properties of our arrays, we have fabricated CB gas sensors operating at RT, whose sensing range is selected just by varying the bias voltage. These results could have important implications for the fabrication of quantum devices based on Si nanocrystals.