Interfaces of Mg and MgOx films with GaAs(100) substrate studied by synchrotron radiation photoemission

The interaction of ultrathin Mg and MgOx films with the GaAs(100) semiconductor substrate was investigated using synchrotron radiation photoemission. The results showed that strong interaction existed between Mg and GaAs leading to the formation of an interface more than 11 Å, while negligible interaction and interdiffusion took place between the MgOx overlayer and the substrate. Different Mg:O2 ratio during the deposition gave rise to the formation of MgOx with different compositions and properties.