We propose a method to obtain the layer-resolved contributions to the reflectance anisotropy signal of semiconductor surfaces which are modeled using the slab approach. Following this method, a microscopic formulation based on the semiempirical tight-binding approach is used to calculate the reflectance anisotropy of two InP(001) surface structures possibly relevant to standard gas-phase epitaxy conditions. It is shown that (i) the elimination of the anisotropy signal from the bottom layers of the slab is essential to correctly compare with the experiment and (ii) the strong low-energy anisotropy characteristic for gas-phase-grown InP surfaces arises from the uppermost atomic layers.

• Received 24 April 2003

DOI:https://doi.org/10.1103/PhysRevB.68.041310