Surfactant-mediated growth of an ordered flat film of an intrinsic liquid metal on a semiconductor surface: Ga onSi(111)−4×1−In

Abstract

The morphology and atomic depth distribution of Ga films grown on $\mathrm{Si}(111)\ensuremath{-}7\ifmmode\times\else\texttimes\fi{}7$ and $\ensuremath{-}4\ifmmode\times\else\texttimes\fi{}1\ensuremath{-}\mathrm{In}$ surfaces at room temperature were studied by using reflection high-energy electron diffraction and characteristic x-ray measurements as functions of glancing angle ${\ensuremath{\theta}}_{g}$ of the incident electron beam. Ga grew into liquid droplets on the $\mathrm{Si}(111)\ensuremath{-}7\ifmmode\times\else\texttimes\fi{}7$ surface, as it does on many other semiconductors. On the other hand, on the $4\ifmmode\times\else\texttimes\fi{}1\ensuremath{-}\mathrm{In}$ surface, Ga grew into an ordered flat film and In floated to the uppermost layer during the growth process of Ga. The resultant top In layer and Ga-Si interface had $\sqrt{3}/2\ifmmode\times\else\texttimes\fi{}\sqrt{3}/2$ and $5\ifmmode\times\else\texttimes\fi{}5$ periodicities, respectively.