The structural characteristics of ZrO2 films along with the interfacial layers deposited on partially strain compensated Si0.69Ge0.3C0.01/Si heterostructure have been, investigated using x-ray diffraction (XRD), high resolution transmission electron microscopy (TEM), time-of-flight secondary ion mass spectroscopy (SIMS), and x-ray photoelectron spectroscopy (XPS) measurements. XRD spectra show the films to be polycrystalline with both monoclinic and tetragonal phases. The ZrO2 film with physical thickness of similar to8.5 nm and an amorphous interfacial layer with a physical thickness of similar to3.6 nm have, been observed by high resolution TEM, SIMS and XPS. SIMS and XPS analyses show the formation of an amorphous Zr-germano-silicate interfacial layer between the deposited oxide and SiGeC films. The electrical properties in terms of capacitance-voltage (C-V), conductance-voltage, current density-voltage, and gate voltage shift (DeltaV(g)) tinder a constant current stressing have,been studied using a metal-insulator-semiconductor (MIS) structure. A dielectric constant of 17.5 for ZrO2 and 7.0 for interfacial Zr-Ge-silicate layer have been calculated from the high frequency C-V characteristics. These dielectrics show an equivalent oxide thickness (EOT) as low as 1.9 nm for ZrO2 and 2.0 nm for the interfacial silicate layer. The MIS capacitor shows an extremely low leakage current density of similar to9x10(-8) A/cm(2) at a gate voltage of -1.0 V, breakdown field of 7 MV/cm based on EOT as the length scale, and moderate interface state density (D-it) of 4.8x10(11) cm(-2) eV(-1) for ZrO2 with interfacial layer. The. Zr-Ge-silicate interfacial layer separately shows a low leakage current density of 3 x 10(-2) A/cm(2) at V-g of -1 V and D-it of 1 x 10(12) cm(-2) eV(-1). Significant improvements in the charge trapping properties udder Fowler-Nordheim constant current stressing in both ZrO2 with the interfacial layer and Zr-Ge-silicate layers have been observed. (C) 2003 American Vacuum Society.