Magnetic and structural properties of evaporated CoxCr1−x/Si(1 0 0) and CoxCr1−x/glass thin films

Series of CoxCr1−x thin films have been evaporated under vacuum onto Si(1 0 0) and glass substrates, where x variations were between 0.51 and 0.61. Thickness ranges from 350 to 4000 Å. DRX measurements show an hcp structure. AGFM measurement gives saturation magnetization ranging from a negligible value to 120 emu/cm3. Coercive field may reach values up to 200 Oe, depending on the percentage of chromium. The saturation magnetization decreases as the Cr content increases. Magnetic force microscopy (MFM) study reveals the absence of stripe domains equilibrium magnetization structure. Brillouin light scattering (BLS) measurements were possible only for the 1800 Å thick sample. They confirm, through the derived magnetic parameters, the absence of stripe magnetic domains as observed by MFM on one hand, and, on the other hand, the adjustment of theoretical and experimental results lead to a stiffness constant 10 times lower than pure Co one. These results are analyzed and correlated.