Effect of oxidized Al prelayer for the growth of polycrystalline Al2O3 films on Si using ionized beam deposition

Abstract Polycrystalline Al 2 O 3 thin films have been grown on Si substrates by ionized beam deposition using an aluminum solid source in O 2 environments. To prevent the aluminum interdiffusion to Si at high substrate temperature ( T s >500°C), the oxidized Al prelayer with a thickness of 3 nm was deposited on the Si substrate at room temperature before Al 2 O 3 deposition, and subsequently polycrystalline Al 2 O 3 films were grown at 700°C. Although Al interdiffusion increased at the interface with increasing T s , the oxidized Al prelayer was effective as a buffer layer on which to grow stoichiometric and crystalline Al 2 O 3 films up to T s =800°C.