Inverse photoemission as a probe for unoccupied electronic states

Inverse photoemission is shown to be complementary to photoemission in probing unoccupied electronic states. The momentum of delocalized valence states can be measured as well as their energy if low electron (photon) energies in the 10-40 eV range are used: Thus, energy band dispersions are obtained for bulk, surface, and adsorbate states which cannot be determined by other techniques. Applications are demonstrated for Si, GaAs, SiO2 and metal-semiconductor interfaces. © 1986.