Chemisorption pathways and Si 2p core-level shifts for the interaction of spherosiloxane clusters with Si(100): Implications for photoemission in Si/SiO2 systems

Using a first-principles density functional approach, we investigate the ch emisorption mechanism for the interaction of spherosiloxane (H8Si8O12) clus ters on Si(100). Our transition state studies reveal that the chemisorption pathway with the lowest activation barrier corresponds to attachment via S i-O bond cleavage across a surface dimer. Using the relaxed surface structu re from this "cracked cluster" model, we calculate Si 2p core-level shifts, including core-hole relaxation effects, and show that the calculated value s are in excellent agreement with the positions and intensities of all the experimentally observed core-level shifts. (C) 2000 American Institute of P hysics. [S0003-6951(00)00526-X].