Structural and Morphological Effect of Ti underlayer on Pt/Co/Pt Magnetic Ultra-Thin Film

Pt(x{\AA})/Co(5{\AA})/Pt(10{\AA}) trilayer films were deposited on naturally oxidized Si(111) substrate to investigate Ti underlayer effect on PMA. A small amount of Ti underlayer promoted the magnetic anisotropy to a perpendicular direction for x=8{\AA} and 10{\AA}. Both GI XRD and STM results showed that the Ti underlayer manipulated the growth of trilayer film. The Pt particles preferably grow the neighborhood of the Ti cluster, giving rise to a relatively smooth layer with a fiber texture fcc (111) structure. By contrast, the absence of Ti underlayer leads to clustered, relatively rough, and randomly oriented nano-crystalline growth. Differences in the growth mode, especially roughness, also appeared as intensity loss in XPS spectra due to shadowing effects. Our results indicate that a traceable amount of underlayer can change the magnetic anisotropy of the film by manipulating film growth.