Single-phase α″-Fe 16N 2 films have been grown epitaxially on Al 2O 3 single crystal substrates by using the thermalized plasma DC-sputtering process at a high sputtering pressure of 250 mTorr. α″-Fe 16N 2 films can be grown at room temperature (RT) as a single crystal phase and have one very intense peak in their X-ray diffraction pattern (XRD), with orientation (1 1 2), and d-spacing=2.4771 Å, and another minor peak with orientation (2 2 4), and d-spacing=1.2388 Å. This phase was reproducible at different nitrogen flow rates (NF) from 1.5 to 3 sccm. The annealing of these films at different temperatures for 3 h lead to the decomposition of the α″-Fe 16N 2 phase. At the annealing temperature T ann=435°C, the structure of the films changes completely to the Fe 3N phase. Increasing the sputtering temperature T s up to 300°C, and using NF=3 sccm leads to other orientations of the α″-Fe 16N 2 phase. At lower nitrogen flows, NF=1.5, 2, and 2.5 sccm, other phases like Fe 2N, Fe 3N and γ-Fe austenite were found in the XRD patterns as phases mixed with the α″-Fe 16N 2 phase. The magnetic properties of the α″-Fe 16N 2 single crystal films which were sputtered at RT were very surprising: they have a very low magnetic moment 4 πM s which varies between 0.097 kG for 1 μm thick films to 0.31 kG for 6 μm thick films. M s was measured using a vibrating reed magnetometer in a magnetizing field of 10 kOe at RT. By using a SQUID magnetometer and magnetizing field up to 50 kOe the 4 πM s at 5 K showed a small increase, 4 πM s=0.35 kG, for the 6 μm thick films. After annealing these films for 3 h at 435°C, 4 πM s increased to 10 kG, which is due to the change of the film crystal structure from the α″-Fe 16N 2 phase to the Fe 3N phase. Also, the hot (300°C) sputtered α″-Fe 16N 2 films under NF=3 sccm have a low 4 πM s equal to the value of the cold sputtered films. The hot sputtered films at lower NF=1.5, 2 and 2.5 sccm showed a small increase of its 4 πM s up to 2 kG depending on the amount of the secondary phases of Fe 2N and Fe 3N which were found in its XRD patterns.