Effects of interfacial nitrogen on the structural and electrical properties of ultrathin $ZrO2$ gate dielectrics on partially strain-compensated SiGeC/Si heterolayers

The interfacial characteristics of high-κ $ZrO2$ on $O2$ and $N2O$-plasma-treated $Si0.69Ge0.3C0.01$ surfaces have been investigated using secondary ion mass spectroscopy and x-ray photoelectron spectroscopy. $N2O$-plasma-treated films show the formation of a nitrogen-rich Zr–germano–silicate interfacial layer between the deposited $ZrO2$ and SiGeC films. The N-treated film has a higher accumulation capacitance (∼1200 pF), lower leakage current density $(7×10−9 A/cm2@−1 V),$ higher breakdown field (∼11 MV/cm), and higher interfacial layer dielectric constant (∼10) than that of the non-nitrogen-treated films. Relatively lower positive trap charge generated by a constant current stressing in N-incorporated dielectric films makes it attractive for scaled metal–oxide–semiconductor field-effect transistor applications.