MAGNETIC-ANISOTROPY IN IRON THIN-FILMS EVAPORATED UNDER ULTRA-HIGH VACUUM

Alpha-iron thin films with thickness ranging between 20 and 1500 nm ha ve been evaporated using an electron gun under ultra-high vacuum condi tions (5.10(-7) Pa). The columnar structure observed in cross-sectiona l TEM is related to the large surface diffusion. From Mossbauer spectr a the spin orientation is deduced and found to be influenced by the co lumn axis. Spins can be obtained perpendicularly to the film plane by rotating the substrate during the deposition. The magnetization of the samples is reduced by about 30 % and the reduction attributed to the interstitial space which increases with the incident angle. The substr ate rotation also decreases Ku(//) by a factor 2 and increases Ku(perp endicular-to).