Germanium interactions are studied on HfO2 surfaces, which are prepared through physical vapor deposition (PVD) and by atomic layer deposition. X-ray photoelectron spectroscopy and temperature-programed desorption are used to follow the reactions of germanium oil HfO2.Germanium chemical vapor deposition at 870 K on HfO2 produces a GeOx adhesion layer, followed by growth of semiconducting Ge-0. PVD of 0.7 ML Ge (accomplished by thermally cracking GeH4 over a hot filament) also produces an initial Ge-0 layer, which is stable up to 800 K. PVD above 2.0 ML deposits semiconducting Get. Temperature programed desorption experiments of similar to 1.0 ML Ge from HfO2 at 400-1100 K show GeH4 desorption below 600 K and GeO desorption above 850 K. These results are compared to Ge on SiO2 where GeO desorption is seen at 550 K. Exploiting the different reactivity of Ge on HfO2 and SiO2 allows a kinetically driven patterning scheme for high-density Ge nanoparticle growth on HfO2 surfaces that is demonstrated. (c) 2006 American Vacuum Society.