Devices studied in this work consist of monocrystalline Silicon micromachined cantilevers, obtained through the bulk micromachining of a BESOl (Back Etch Silicon On Insulator) wafer. Cantilevers are functionalized by means of a sensitive polymer layer. These devices have been employed in the detection of Volatile Organic Compounds (VOCs) through different transduction principles. State-of-thc-art sensitivities have been obtained.