Abstract
Highβmoment soft magnetic Fe~65~Co~35~ thin films with well inβplane uniaxial anisotropy were obtained by cosputtering on Co~93~Fe~7~, Ni~80~Fe~20~, Cu and Fe underlayers. The singleβlayer Fe~65~Co~35~ film with thickness of 100 nm shows a magnetic anisotropy. The coercivity along easy axis H ~ce~ and that along hard axis H ~ch~ are equal to 3.3 kA/m and 2.1 kA/m, respectively. The soft magnetic properties of Fe~65~Co~35~ films were much improved by using an underlayer. The H ~ce~ and H ~ch~ of Fe~65~Co~35~ films with Ni~80~Fe~20~, Co~93~Fe~7~ and Cu underlayers can be reduced to 0.9β1.1 kA/m and 0.08β0.20 kA/m, respectively. For films with Fe underlayer, the H ~ce~ and H ~ch~ reduced to 1.1 kA/m and 0.6 kA/m, respectively. In the case of Co~93~Fe~7~, Ni~80~Fe~20~ and Fe underlayers, the coercivity of films did not depend remarkably on the thickness t of underlayer at t > 1 nm. While in the case of Cu underlayer, the coercivity of films changed remarkably with increasing underlayer thickness. It was shown that the texture of doubleβlayered underlayer/Fe~65~Co~35~ films is dependent on the material and the thickness of underlayer. The influence of the underlayer on the surface morphology and microβmagnetic structure of films were investigated by AFM and MFM. It was suggested that the modification of the structure of Fe~65~Co~35~ films by using an underlayer is an important way to improve their soft magnetic properties. (Β© 2006 WILEYβVCH Verlag GmbH & Co. KGaA, Weinheim)