Anisotropic dynamic polarization of surface vibrations associated with H on stepped Si(111)

Using polarized infrared spectroscopy, stretching and bending vibration modes of H chemisorbed on 4° and −9° misoriented Si(111) surfaces were investigated. Both the stretching and bending modes and their polarization responses were explained by surface structures such as monohydrides on a terrace, monohydride chains at the step edge of a (111) micro-facet and vertical dihydrides at the step edge of a (001) micro-facet. The dynamic polarizations for these bending vibration modes were anisotropic, i.e. the polarizations for the two step modes were along 〈110〉, while that of the terrace mode was in the (111) plane.