A RHEED study of the growth of antimony on tungsten (110)

Abstract

Antimony has been evaporated under ultrahigh vacuum conditions on to an atomically clean tungsten (110) surface at 300K. The structural changes occurring from submonolayer up to 60 mean monolayers coverage, have been monitored using reflection high-energy electron diffraction. Deposition under these conditions yielded a series of submonolayer structures followed by a spontaneous change of symmetry at a coverage of theta approximately=2 from two-fold to four-fold symmetry. Further deposition caused the growth of two types of long, thin three-dimensional islands of antimony, one similar to bulk antimony, the other an abnormal FCC phase with the same lattice constant. Both types of islands grew with their pseudocubic (100) face parallel to the (110) substrate and the relaxation from perfect four-fold symmetry was detected by the RHEED. Subsequent electron microscopic examination of the thicker films confirmed the structural results deduced from the RHEED experiments.