Infrared study of adsorption and thermal decomposition of Si2H6 on Si(100)

We have investigated the adsorption and thermal decomposition of disilane o n Si(100) (2 x 1) using infrared absorption spectroscopy. We demonstrate th at at room temperature, disilane dissociatively adsorbs onto the surface wi th the dimer bond unbroken, to produce mono-, di-, and tri-hydride species. At low coverages, the disilane molecule adsorbs on the surface without bre aking the Si-Si bond of the molecule. Thermal annealing following room-temp erature adsorption of disilane produces a hydrogen-terminated adatom dimer (HSi-SiH) and an isolated monohydride species. We suggest that these hydrid e species are generated through the rupture of the substrate dimer bonds. H ydrogen desorption from the isolated monohydride occurs at much lower tempe rature than that from the adatom dimer. (C) 2000 Elsevier Science S.A. All rights reserved.