Adsorption and dissociation of disilane on Si(001) studied by STM

doi:10.1016/0039-6028(93)90079-Y

Surface Science

Volume 298, Issue 1, 10 December 1993, Pages 50-62

https://doi.org/10.1016/0039-6028(93)90079-Y Get rights and content

Abstract

The surface-adsorbed fragments resulting from the room-temperature adsorption and dissociation of disilane (Si₂H₆) on Si(001) are observed and identified using scanning tunneling microscopy (STM). The predominant fragments are H and SiH₂, which are identified by the symmetries of their binding sites on the surface. H atoms often bind near single or double dimer vacancy defects. We find that adsorbed H atoms induce buckling of the dimer rows on the Si(001) surface, while SiH₂ groups do not. This difference is ascribed to differences in the electronic structure of the two surface-bound species. No systematic correlation between the positions of the SiH₂ groups is evident, which indicates that the fragments of a single disilane molecule are not localized in a small region. This fact suggests that at least some of the molecular fragments from disilane dissociation are mobile on the Si(001) surface at room temperature. Further decomposition of the SiH₂ fragments can be induced by annealing, which produces surface structures similar to those seen in molecular-beam epitaxial growth of silicon: small asymmetric islands form with low disilane coverages, whereas higher coverages give multilayer island growth.

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Adsorption and dissociation of disilane on Si(001) studied by STM

Abstract

Chem. Phys. Lett.

Physica B

Chem. Phys. Lett.

Surf. Sci.

Surf. Sci.

Solid State Commun.

Chem. Phys. Lett.

Surf. Sci.

J. Chem. Phys.

Appl. Phys. Lett.

J. Chem. Phys.

Phys. Rev. B

J. Vac. Sci. Technol. A

Phys. Rev. B

J. Vac. Sci. Technol. A

Phys. Rev. Lett.

Phys. Rev. B