Abstract
Conventional wet cleaning and ultrahigh-vacuum (UHV) -annealed cleaning prior to thermal oxidation were compared with their effects on SiO2/Si (001) interface roughness. In comparison with the wet cleaned surfaces, atomically flat interfaces were obtained and the roughness was reduced to less than 0.1 nm in RMS for the UHV-annealed surfaces by annealing the surface at 1100°C in UHV (<5×10-10 Torr). This planarizatin was remarkable in the ultrathin oxide region (<4 nm).