Magnetic and structural properties of Sm/sub 2/Fe/sub 10/Co/sub 7//M/sub x/C/sub y/ thin films

摘要

The structural and magnetic properties of Sm/sub 2/Fe/sub 10/Co/sub 7//M/sub x/C/sub y/ (M=Al and Si; x/spl ges/0 and y/spl ges/0) multilayer films with Ta underlayers and overlayers before and after annealing at 700/spl deg/C for 5-12 min have been fabricated and studied. Structural studies show evidence of layer diffusion upon annealing. X-ray diffraction shows that the samples after annealing consist of a soft phase, /spl alpha/-Fe, and a hard phase with the 2-17-type structure. The samples studied have in-plane anisotropy with single hysteresis loops indicating that the two phases are strongly exchange coupled. After annealing, the coercivity of samples with Al/sub x/C/sub y/ is found to increase with increasing Al/sub x/C/sub y/ composition to a maximum of 3.3 kOe. The energy products for these samples are found to increase from 1.4 MGOe for SmFeCo to 8 MGOe for SmFeCo with Al/sub x/C/sub y/.