Furnace O-2 Annealing Growth of Cu2O Thin Film for Thin-Film Transistors at Low Temperature

Abstract

Cuprous oxide (Cu2O) film has been grown via O-2 annealing on Si(100) with a furnace. The impact of Si surface passivation by O-2 annealing growth was investigated. We studied variations in the surface composition of Cu2O at various furnace annealing temperatures and amounts of O-2 gas. Prolonged annealing of Cu2O results in a formation of a thick layer of Cu2O at the surface, while a short annealing time of Cu2O produces a thin film of Cu metal. The thick Cu2O film generated from the sputtering deposited a Cu layer, which was oxidized by heating at 200-400 degrees C in 10-30 sccm of O-2 gas. In the case of Cu film, the extent of reduction varies with the thermal history of the samples, with prolonged annealing producing a more reducible surface. Cu2O thin film grown from a Cu metal layer shows a diffusion of lattice oxygen corresponding to the characteristics of the thin film.