The Atomic Layer Deposition of HfO₂ and ZrO₂ using advanced metallocene precursors and H₂O as an oxidant

The atomic layer deposition of HfO2 and ZrO2 thin films was investigated using (CH3C5H4)2Hf(CH3)2, (CH3C5H4)2Hf(OCH3)(CH3), (CH3C5H4)2Zr(CH3)2, and (CH3C5H4)2Zr(OCH3)(CH3) precursors at deposition temperatures between 300 and 500 °C using water vapor as the oxidant. A surface-limited growth mechanism was confirmed at 350 °C for all metal precursors examined. The processes provided nearly stoichiometric HfO2 and ZrO2 films with carbon and hydrogen concentrations below 0.5 and 1.0%, respectively, for representative samples. All films were polycrystalline as deposited and possessed a thin interfacial SiO2 layer. The capacitance-voltage and current density-voltage behavior is reported and discussed for capacitor structures containing films from this study.