Rapid growth of ultra thin SiO2 films by a large-area electron beam

Abstract

Rapid growth of ultra thin oxide films (40–180A) of silicon using a low-energy large-area electron beam has been performed with a pressure ratio of 3∶1 (O2/He) and a total pressure of 0.5–0.7 Torr. A higher oxidation rate of about 625A2/s is found for shorter irradiation time of the e-beam in the e-beam dose range 0.75–3 Coulomb/cm2 and at lower substrate temperature 540–740°C. AES and XPS demonstrated a rapid electron-stimulated oxidation process of the Si surface. For the grown ultra thin oxide films, C-V characteristics, dielectric strength, uniformity of the film over the entire Si wafer and its thickness as a function of the processing time of the e-beam are also presented.