Epitaxially grown Fe₁₆N₂single-crystal films with high saturation magnetization prepared by facing targets sputtering

alpha "-Fe 16 N 2 single-crystal films were prepared with a facing targets sputtering (FTS) system onto single-crystal NaCl substrates, at a deposition rate as high as 2.0 AA s -1 . In the process of deposition, the partial pressures of argon and nitrogen gases were held at 0.3 Pa and 0.05 Pa, respectively. The effect of the substrate temperature on the formation of Fe-N phases was investigated in detail. The crystal structure of the Fe-N films was examined with an x-ray diffractometer and a transmission electron microscope. At T s =150 degrees C, single-crystal alpha "-Fe 16 N 2 grows epitaxially on alpha -Fe with an orientation relationship of alpha "-Fe 16 N 2 (110)// alpha Fe (110), Fe 16 N 2 (111)// alpha -Fe(111). When T s =100 degrees C and 200 degrees C, the Fe-N films contain more alpha '-martensite and gamma '-Fe 4 N, respectively. The integrated electron diffraction pattern of the alpha "-Fe 16 N 2 single crystal in the (111) direction was clearly observed. The film revealing a single-crystal electron diffraction pattern exhibits a high saturation magnetization M s up to 2050 emu cc -1 , the high M s of the alpha "-Fe 16 N 2 phase.