Surface modification of silicon nanowire field-effect devices with Si-C and Si-N bonded Monolayers

The research work was mainly focused on the surface modification/surface functionalization of active-gate areas of silicon nanowire field-effect transistor devices (Si-NW FET) using hydrogen terminated surfaces, Si-C and Si-N bonded monolayers and subsequent bioimmobilization for biosensor applications. Experiments were conducted on planar silicon samples for contact angle measurements and x-ray photoelectron spectroscopy (XPS) for the confirmation of step wise surface modification process. Efficiency of surface amendments/modification on Si-NW FET devices was tested and monitored by scanning electron microscopy (SEM), fluorescence spectroscopy, and atomic force microscopy (AFM) as well as electrical measurements by front and back gating the devices in air and in aqueous solutions. Contact angle measurements are very good to have an immediate idea of surface physical property in terms of hydrophobicity or hydrophilicity. ..