PERPENDICULAR MAGNETIC-ANISOTROPY OF FE-CR-N FILMS PREPARED BY DC REACTIVE SPUTTERING

Fe-Cr-N ternary films prepared by DC magnetron facing-target sputterin g show perpendicular magnetic anisotropy. Upon appropriate adjustment of the chemical composition and deposition parameters, saturation magn etization of 0.37-0.5 Wb/m(2) (300-400 emu/cm(3)) and perpendicular co ercivity of 6.4 x 10(4)-8.8 x 10(4) A/m (800-1100 Oe) are detected in the Fe-Cr-N films. X-ray diffraction measurements reveal that the film s with large perpendicular anisotropy generally consist of the fine-gr ain alpha-Fe(Cr) phase and the gamma'-(Fe, Cr)(4)N-x (x < 1) phase hav ing a pronounced (200) texture. By TEM observation, we found that the nonmagnetic gamma'-(Fe, Cr)(4)N-x phase displays columnar growth and t hat the small ferromagnetic alpha-Fe(Cr) grains of about 2-20 nm diame ter are located at grain boundaries of gamma'-(Fe, Cr)(4)N-x grains in the Fe71Cr20N9 film.