Ultrathin zirconium oxide films as alternative gate dielectrics Available to Purchase

$ZrO2$ films were deposited on Si(100) wafers by the rapid thermal chemical vapor deposition process using a zirconium (IV) t-butoxide $Zr(OC4H9)4$ precursor and oxygen. Interfacial zirconium silicate formation was observed by high resolution transmission electron microscopy and medium energy ion scattering. The intermixing of the interface can be suppressed by forming a thin silicon nitride layer on the silicon substrate prior to $ZrO2$ deposition. The dielectric constant of $ZrO2$ achieved in this work is 15–18 with very small capacitance–voltage hysteresis, ideal for metal–oxide–semiconductor field effect transistor (MOSFET) application. The NMOSFET device has good turn-on characteristics, however, the transconductance is lower than expected due to the incomplete removal of zirconium silicate at the source and drain contacts and poses integration challenges to use $ZrO2$ as the gate dielectric material.