Room-temperature photoreflectance is employed to investigate the Fermi level pinning and surface state density of a GaAs0.65 Sb0.35 surface intrinsic- n+ (SIN+) structure. Based on the thermionic emission theory and current-transport theory, the surface Fermi level VF and surface state density are determined experimentally from the dependence of the surface barrier height on the pump beam intensity. The surface state density D s is estimated as approximately 1.91× 1013 cm-2, and the Fermi level is located 0.63 eV below the conduction band edge at the surface. By sequential etching of the intrinsic layer, the Fermi level pinning in GaAs0.65 Sb0.35 SIN+ structure is further demonstrated.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)