Indium coverage of the Si(111)- 7×3 -In surface

Abstract

The indium coverage of the Si(111)-$\sqrt{7}\ifmmode\times\else\texttimes\fi{}\sqrt{3}$-In surface is investigated by means of x-ray photoelectron spectroscopy and first-principles density functional theory calculations. Both experimental and theoretical results indicate that the In coverage is a double layer rather than a single layer. Moreover, the atomic structure of the Si(111)-$\sqrt{7}\ifmmode\times\else\texttimes\fi{}\sqrt{3}$-In surface is discussed by comparing experimental with simulated scanning tunneling microscopy (STM) images and scanning tunneling spectra with the calculated density of states. Our structural assignment agrees with previous studies, except for the interpretation of experimental STM images.