Formation of HfO2/GaAs(001) interface with Si interlayer

Composition and electrical characteristics of HfO
₂
/Si/GaAs(001) interface formed by e-beam evaporation of Hf in NO
₂
ambient on MBE-grown Si/GaAs structure, were studied by XPS and C-V methods. The deposition of HfO
₂
on Si-passivated GaAs(001) surface leads to the formation of sharp HfO
₂
/Si/GaAs interface without oxidation of Si interlayer. AFM studies of the HfO
₂
/Si/GaAs(001) interface show that HfO
₂
deposition preserved the flatness of the surface, keeping the mean roughness on the terraces on a level of approximately 0.2-0.3 nm.