SOFT-MAGNETIC PROPERTIES OF COMPOSITIONALLY MODULATED FE/AL FILMS

Soft-magnetic properties of Fe/Al compositionally modulated multilayer films prepared in the low argon pressure of 2 mTorr with double target dc magnetron sputtering have been studied. Characteristic x-ray diffraction peaks corresponding to artificial structure on [Fe(4-50 angstrom)/Al(8 angstrom)]150 multilayer films were observed. Maintaining a constant Al layer thickness of 8 angstrom, the coercivity in the hard axis rapidly decreases from 50 Oe to < 1 Oe as the Fe layer thickness increases from 4 to 24 angstrom. When the Fe/Al thickness ratio is around 3, minimum coercivity was obtained. In the region of bilayer thickness ratio delta-Fe/delta-Al < 3.0, the M(s) per Fe unit volume decreases with decreasing delta-Fe/delta-Al. The higher resistivity was obtained in the films of delta-Fe/delta-Al < 3.0, and resistivity decreases as delta-Fe/delta-Al increases. The internal film stress also decreases as delta-Fe/delta-Al increases. The [Fe(20 angstrom)/Al(8 angstrom)]150 multilayer film exhibited a low coercivity 0.5 Oe, a high saturation magnetization 1210 emu/cm3, and a high resistivity 119-mu-OMEGA-cm.