Surface band bending on clean and oxidized (110)-GaAs studied by Raman spectroscopy

We demonstrated that the measurement of a bulk phonon property, i.e. the resonantly excited symmetry forbidden LO-Raman intensity via its dependence on the surface electric field, is a comparatively easy, sensitive and high spatial resolution method to measure surface Fermi level positions in polar semiconductors as a function of e.g. cleavage conditions, oxygen exposure and doping.