Magnetic properties of CoFeB-SiO_2 nanocomposite and (Co_(40)Fe_(40)B_(20))X(SiO_2)_(100-X)/α-Si:H_n multilayer films

摘要

Magnetic properties of (Co_(40)Fe_(40)B_(20))X(SiO_2)_(100-X) nanogranular composite films, [(Co_(40)Fe_(40)B_(20))X(SiO_2)_(100-X)/α-Si:H]_n multilayer films and layered (Co_(40)Fe_(40)B_(20))X(SiO_2)_(100-X) films with X ranging from 30 to 80 have been characterized by means of magnetic measurements and ferromagnetic resonance. Layer thickness was varied between 1.3 and 6 nm. Thermal decrease of (Co_(40)Fe_(40)B_(20))X(SiO_2)_(100-X) composite magnetization follows the T~(3/2) law. The spectrum of standing spin-wave has been detected in the perpendicular experiment configuration for films with the metal phase content above 48 vol.%. It is found that the H_r(n~2) dependencies are non-linear. Such behavior is probably caused by the fluctuations of magnetic parameters (the magnetization and the ferromagnetic exchange coupling) in nanocomposite films. A comparison between the magnetic properties of (Co_(40)Fe_(40)B_(20))X(SiO_2)_(100-X) granular films and [(Co_(40)Fe_(40)B_(20))X(SiO_2)_(100-X)/α-Si:H]_n multilayer films was carried out.