Photoemission study on the Sb-induced reconstruction of the Si(1Â 1Â 2) surface

This study investigated the Sb-induced reconstruction of the Si(1 1 2)2 × 1 surface using low energy electron diffraction (LEED) and synchrotron radiation photoelectron spectroscopy (SRPES). When Sb was deposited on the clean Si(1 1 2) surface at 300 °C, a sharp hexagonal LEED pattern with weak “n/5” fractional spots was observed, which is very similar to one of the Sb/Si(1 1 1)1 × 1 surfaces. The Si 2p and Sb 4d core level photoemission spectra were measured. The analysis results of the SRPES showed that the Si 2p core-level spectrum is composed of two surface-related components: a surface component at +0.2 eV and a small surface-related component at -0.2 eV with respect to the bulk component. In addition, the Sb 4d core-level spectrum was well reproduced with one doublet component. The results revealed that Sb atoms were adsorbed at unique sites on a Si(1 1 1)1 × 1 surface. On the basis of the nanofacet structure model of the Sb/Si(1 1 2) surface suggested by a previous scanning tunneling microscopy (STM) study, the structural model of the Sb/Si(1 1 2) surface was compared with the LEED pattern and the SRPES results.