Low temperature pulsed laser deposition of textured γ′-Fe4N films on Si (1 0 0)

Low-temperature reactive pulsed laser deposition (PLD) was used to prepare iron nitride films. The textured γ′-Fe4N films with (0 0 1)-orientation were deposited on Si (1 0 0) substrate with Fe buffer layer at a substrate temperature as low as 150 °C. The (0 0 1)-oriented γ′-Fe4N film grew on the Fe buffer layer with a 3.5-nm thick amorphous interlayer, which eliminated the lattice mismatch stress between them. The films showed a columnar granular morphology with an average lateral grain size of approximately 110 nm. The films exhibited good soft magnetic properties with a high in-plane Mr/Ms value of 0.84. The magneto-optic Kerr effect results indicated an in-plane magnetic isotropy and confirmed the high remnant ratio of the γ′-Fe4N films.

Research highlights
► γ′-Fe4N films have gained increasing interests as potential application as spintronics magnetic devices. This is the first time that the (0 0 1)-oriented γ′-Fe4N film was deposited on Si (1 0 0) substrate at relatively low deposition temperature of 150 °C by pulsed laser deposition.
► The films exhibited good soft magnetic properties with a high in-plane Mr/Ms value of 0.84. In addition, the magneto-optic Kerr effect measurement demonstrated an in-plane magnetic isotropy of the film.
► The low temperature deposition of (0 0 1)-oriented γ′-Fe4N films on silicon substrate is important for the applications in magnetic devices and for the integration of magnetic devices into silicon technology.