Structural and dielectric properties of energetically deposited hafnium oxide films

Amorphous hafnium oxide films, energetically deposited at room temperature from a filtered cathodic vacuum arc (FCVA) onto Si substrates, exhibit low current leakage (11 μA cm-2 in an electric field of 100 kV cm-1), a dielectric constant (k) of 17 and a refractive index exceeding 2.1 over the visible spectrum. Cross-sectional transmission electron microscopy, energy-dispersive x-ray spectroscopy and electron energy loss spectroscopy revealed an amorphous microstructure and higher film density when compared with HfO2 deposited by reactive direct-current magnetron sputtering. The superior properties and higher density of the FCVA HfO2 are attributed to the elevated energy of the depositing flux.