Magnetic Properties of Transition Metal Nitride--Synthesis of Iron Nitride by High-Dose Nitrogen Ion Implantation--

Nitrogen ions (N
₂
⁺
) were implanted into pure iron films in an attempt to produce Fe
₁₆
N
₂
and other iron nitride phases. Ions were implanted at 150 keV and dosages were ranged from 2 × 10
¹⁶
to 2.11 × 10
¹⁷
ions/cm
²
, and magnetization measurements and X-ray diffraction studies performed. Ferromagnetic Fe
₃
N and Fe
₄
N phases were found intermixed with the α-Fe, but there was no evidence of Fe
₁₆
N
₂
. The saturation magnetization decreased slowly with increasing dosage, but dropped abruptly by 40 percent at the highest dose, due to the formation of a paramagnetic Fe
₂
N phase. This method is suggested as a means of improving iron surface properties without greatly degrading the magnetic properties.