XAFS and X-ray reflectivity study of III-V compound native oxide/GaAs interfaces

Fluorescence-mode XAFS has been used to study the local environment about c hosen atomic species such as Ga and As in bulk oxide Al1-xGaxAs (x=0. 96) a nd at the interface between thin (300 Angstrom) oxidized Al1-xGaxAs (x=0.94 ) film and GaAs substrate in total external-reflection mode. X-ray reflecti vity experiments have also been employed to investigate the density profile of the oxide film on a GaAs substrate revealing the density profile as a f unction of depth. It is important to find out how the As is incorporated at the interface, the interfacial strain, and related local structural parame ters for understanding that may be central in developing high performance I II-V MOSFET devices.