Performances of hafnium oxide produced by radio frequency sputtering for gate dielectric application

The search for new dielectric materials to be used in metal-insulator-semiconductor (MIS) structures to replace the silicon oxide (SiO2) has been growing up. The aim is to have materials with high dielectric constants that could allow the use of thicker films and so, to reduce the role of leakage currents that happens in devices using very thin SiO2 layers or to allow the MIS devices to support high currents, besides having a retain memory effect. In this work, we present data concerning the production of hafnium oxide (HfO2) thin films by radio frequency (rf) sputtering that present suitable characteristics to be used as a gate dielectric, taking advantage of its high dielectric constant and stoichiometry reached under certain deposition conditions. Data concerning the role of the deposition parameters in the films structure and in the electrical properties of the films produced using capacitance-voltage (C-V) and current-voltage (I-V) measurements will be shown, together with data concerning the degree of films' compactness measured by spectroscopic ellipsometry (SE).