THEORY OF DIPOLE GENERATION AT CLEAVED SEMICONDUCTOR SURFACES

We have computed the dipole moments for a range of Si clusters cleaved along both glide and shuffle (111) planes. The moments arise due to t he breaking of inversion symmetry by the crack. The values are somewha t sensitive to the cluster size, but there appears to be a clear indic ation that the dipole moments from glide plane cleavage are some two o rders of magnitude greater than for shuffle plane cleavage. This provi des a difference between the two kinds of cleavage that may be useful for determining which occurs, and hence decide on surface models.