GROWTH AND STRUCTURE OF hcp Ti FILMS ON Al(111) SURFACES

The structure of thin Ti films grown on Al(111) surfaces at room temperature has been studied using high energy ion scattering/channeling (HEIS), X-ray photoelectron spectroscopy (XPS), low energy ion scattering (LEIS), low energy electron diffraction (LEED) and X-ray photoelectron diffraction (XPD). Our results show that Ti grows in the SK mode on the Al(111) surface. Ti atoms form a two-dimensional overlayer up to a deposition of about 2 ML Ti, followed by three-dimensional island growth with additional Ti deposition. The Ti islands cover the surface completely at about 12 ML of Ti deposition. XPD results show that the Ti overlayer has a well-ordered hcp Ti(0001) structure on the fcc Al(111) surface, in remarkable contrast to the fcc Ti film growth observed on Al(001) and Al(110) surfaces.