The effect of post-oxidation N 2 annealing and post-metallization forming-gas annealing on the electrical properties of Pt/Hf-silicate (3 nm)/Si 0.8 Ge 0.2 (100)/ n-type Si(100) metal-oxide semiconductor (MOS) capacitors is reported. Capacitance-voltage (C-V) and current density-voltage (J-V) measurements of asgrown, 3-nm-thick, hafnium-silicate films containing ϳ12at.%Hf indicate a large number of bulk and interface traps with a current density of ϳ10 Ϫ2 A/cm 2 at V FB ϩ 1 V. Post-ultraviolet (UV)/O 3 oxidation annealing in N 2 at 350°C for 30 min leads to a significant improvement in the electrical characteristics of the film. A post-metallization anneal (PMA) at 450°C for 30 min in forming gas (90% N 2 :10% H 2 ), however, degraded the electrical properties of the films. X-ray photoelectron spectroscopy (XPS) analyses of the forming-gas-annealed films indicate that a possible cause for the degradation in electrical properties is the hydrogen-induced reduction of GeO 2 in the interfacial Si x Ge 1-x O 2 oxide layer to elemental germanium. Implications for the introduction of hafnium silicate as a viable gate dielectric for SiGe-based devices are discussed.