Atomic-scale determination of band offsets at the Gd_2O_3/GaAs (100) hetero-interface using scanning tunneling spectroscopy

摘要

Direct measurements of band profile and band offsets across the Gd_2O_3/GaAs(100) hetero-interface have been performed using cross-sectional scanning tunneling microscopy and spectroscopy. The spatial variation of the local density of states with atomic precision revealed the interfacial band alignment in this model high-K/III-V system. In conjunction with the theoretical modeling, the band offsets for both conduction and valence states are identified, revealing critical information about the electrostatic potential landscape of the GaAs semiconductor transistor with a Gd_2O_3 gate dielectric.