Interface engineering by metal electrode scavenging of Gd2O3 films sputtered on Si

Amorphous Gd
₂
O
₃
thin films were grown on Si by high-pressure sputtering (HPS). In order to minimize the uncontrolled interfacial SiO
_x
, a metallic Gd film was deposited in Ar atmosphere, and afterwards it was in situ plasma oxidized in an Ar/O
₂
plasma. For postprocessing interfacial SiO
_x
reduction several top metal electrodes were studied: platinum, aluminum and titanium. It was found that Pt did not react with the electrode or interface. On the other hand, Al reacted with the dielectric reducing capacitance. Finally, Ti was effective in reducing the SiO
₂
interface thickness without severely compromising gate dielectric leakage.