HIGH-QUALITY FE(001) SINGLE-CRYSTAL FILMS ON MGO(001) SUBSTRATES FOR ELECTRON SPECTROSCOPIES

Fe films have been prepared in ultrahigh vacuum by epitaxial growth on MgO(001) substrates. Spin-resolved inverse photoemission measurements indicate that nonannealed overlayers display lower spectroscopic qual ity than the corresponding bulk system. Low energy electron diffractio n and x-ray photoemission reveal that annealing promotes oxygen surfac e segregation giving rise to a c(2 x 2) reconstruction even in several hundred Angstrom thick films. It is found that high-quality Fe(001) s ingle crystal films with clean and well ordered surfaces can be obtain ed after high temperature annealing (similar to 600 degrees C) of rela tively thick films (>1000 Angstrom). (C) 1998 American Vacuum Society. [S0734-2101(98)05604-8].