Reactive epitaxy of beryllium on Si(1 1 1)-(7×7)

Scanning tunneling microscopy (STM) and photoelectron spectroscopy (PES) have been used to investigate the nucleation, growth, and structure of beryllium on Si(1 1 1)-(7×7). STM indicates that a chemical reaction occurs at temperatures as low as 120 K, resulting in a nano-clustered morphology, presumed to be composed of a beryllium silicide compound. Upon annealing to higher temperatures, PES data indicate that beryllium diffuses into the selvage region. High temperature annealing (∼1175 K) results in the formation of a universal ring cluster structure suggesting a Be–Si bond length less than 2.5 Å, in agreement with previous calculations regarding hypothetical Be2Si.