Growth and electronic structure of thin epitaxial Pd and Co films on W(100)

Pd and Co films deposited on a W(100) surface were studied with reflection high-energy electron diffraction, Auger electron spectroscopy, and ultraviolet photoemission spectroscopy. The films grow initially pseudomorphic. At a critical coverage of 2.4 ML suddenly (112{}0) oriented hcp islands form. These hcp islands have a pronounced narrow valence-band feature close to the Fermi edge, which can cause ferromagnetism. At elevated temperatures the islands become very large and three-dimensional alloying occurs above 600 K for Pd and 400 K for Co. In Pd films an interface alloy forms around 500 K. {} 1996 The American Physical Society.