Hydrogen atoms as a probe of the optical anisotropy of indium phosphide (0 0 1)

The reflectance difference spectra of the InP(0 0 1) (2×1) and δ(2×4) reconstructions have been characterized using hydrogen as a probe of the surface bonds. Bands observed at 1.9, 3.1, 4.1, and 4.6 eV on the (2×1) and at 2.8, 3.7, and 4.6 eV on the δ(2×4) decrease in direct proportion to the hydrogen coverage. By comparing the changes in the reflectance difference spectra to the changes in the atomic structure of the surfaces, it is possible to relate the peaks to transitions involving specific valence bond states.