Heteroeptiaxial growth of alloy monolayers on W(110)

Abstract We studied the initial growth of Co 1 - x Fe x films on W(1 1 0) using scanning tunneling microscopy and spectroscopy (STM and STS), in combination with low-energy electron diffraction (LEED). For Co-rich alloys the deposition at room temperature followed by high-temperature annealing is not equivalent to the deposition at high substrate temperatures, in contrast to the case of Fe-rich alloys. While room temperature deposition results in a structure consisting of small islands even after annealing, deposition at high substrate temperatures leads to large coalesced areas. Sequential deposition of pure Co and pure Fe results in phase separated areas of Co- and Fe-rich areas. Only, in…