Hard x-ray photoelectron spectroscopy study of As and Ga out-diffusion In In_(0.53)Ga_(0.47)As/Al_2O_3 film systems

摘要

Hard x-ray photoelectron spectroscopy (HAXPES) was performed on In_(0.53)Ga_(0.47)As/Al_2O_3 gate stacks as deposited and annealed at 400 ℃, 500 ℃, and 700 ℃ to test for out-diffusion of substrate elements. Ga and As core-level intensities increase with increasing anneal temperature, while the In intensity decreases. HAXPES was performed at two different beam energies to vary the surface sensitivity; results demonstrate Ga and As out-diffuse into the As_2O_3 film. Analysis suggests the presence of an interlayer containing Ga and As oxides, which thickens with increasing anneal temperature. Further diffusion, especially of Ga, into the As_2O_3 film is also observed with increasing anneal temperature.