InSb(100) reconstructions probed with core-level photoemission.

Abstract

The InSb(100) surface was grown using the techniques of molecular-beam expitaxy. The surface was found to undergo several surface reconstructions, including a c(4\ifmmode\times\else\texttimes\fi{}4), a c(8\ifmmode\times\else\texttimes\fi{}2), an asymmetric (1\ifmmode\times\else\texttimes\fi{}3), a symmetric (1\ifmmode\times\else\texttimes\fi{}3), and a (1\ifmmode\times\else\texttimes\fi{}1). High-resolution photoemission spectra of the In and Sb 4d core levels clearly exhibited surface-shifted components for some of these reconstructed surfaces. Analyses of the In and Sb core-level photoemission intensities as well as of the surface to bulk intensity ratios for the c(4\ifmmode\times\else\texttimes\fi{}4) and c(8\ifmmode\times\else\texttimes\fi{}2) structures were carried out. The c(4\ifmmode\times\else\texttimes\fi{}4) surface was found to be terminated with 1--(3/4 monolayers of Sb, while (3/4 monolayer of In was found to be the termination of the c(8\ifmmode\times\else\texttimes\fi{}2) surface. Structural models are proposed for the c(8\ifmmode\times\else\texttimes\fi{}2) and c(4\ifmmode\times\else\texttimes\fi{}4) based upon these coverages and upon existing models of the similar GaAs(100) structures.