Magnetic properties of electron beam evaporated CoPt alloy thin films

Abstract

A systematic study of the magnetic and structural properties of Co/sub 75/Pt/sub 25/ alloy thin films has been carried out. Films deposited onto Al/sub 2/O/sub 3/(0001), Al/sub 2/O/sub 3/(1120) and MgO(111) substrates at temperatures from 230 to 450/spl deg/C exhibit a large perpendicular magnetic anisotropy (>1.0/spl times/10/sup 7/ erg/cm/sup 3/). The Co/sub 3/Pt hcp ordered state is also observed by X-ray and electron diffraction and this ordered state is a plausible origin of the strong anisotropy, especially in those films for higher substrate temperature (>300/spl deg/C).