Substrate temperature and oxygen pressure dependence of pulsed laser-deposited Sr ferrite films

ORIENTED BARIUM, STRONTIUM FERRITE FILMS PULSED LASER DEPOSITED ON YSZ(100) AND Si(100) SUBSTRATES

“…The larger percentage in plane mismatch, between the SrM and YSZ (~12%; smaller misfit is possible by rotation of the SrM lattice relative to the substrate) compared to SrM and Ah03 (7%) may produce a larger strain which introduces lattice defects resulting in broadening. AFM micrographs revealed a granular microstructure with characteristic pyramidal growth pattern for each hexagonal grain, similar to that obseIVed for SrM on (0001) Ah03 [1]. Because of the SrM layered structure, the rapid growth direction of the film is in directions perpendicular to the c-axis, that is, material is most easily added at an edge.…”

“…In an earlier investigation [1] we have shown that growth of perpendicularly oriented, pulsed laser deposited (Pill) SrM films on (0001) sapphire (a.-Al2<>J) requires high substrates temperatures (-840°C) and oxygen pressures in the neighbourhood of 0.1 mbar. Although AhCh and M-hexaferrites have different crystal lattices, both structures are based on hexagonal close packing arrangements of oxygen ions.…”

Effects of a Pt underlayer and interlayer on the growth texture of strontium ferrite thin films

“…The -axis orientation needs to be controlled to be perpendicular to the film plane for perpendicular recording applications, or needs to be controlled to be either in-plane or randomly oriented for longitudinal recording applications. It was shown that the -axis orientation of SrM films can be made either perpendicularly or randomly orientated by changing the process parameters and choice of different substrates [5]- [7]. It was also found that Pt is effective in controlling the -axis orientation for barium ferrite films [8], [9].…”

Control of magnetization reversal in oriented strontium ferrite thin films

“…In the literature, there are numerous articles on the thin films of hexagonal ferrites like Barium Ferrite and Strontium Ferrites. 6,[7][8][9] Several techniques such as Pulsed Laser Deposition (PLD) 8,9 , sputtering 10 , and plasma spraying 11 are used for the deposition of hexagonal ferrite thin films. Out of all these techniques, the PLD has emerged as an effective deposition technique for the oriented or epitaxial growth of the oxide hexagonal ferrite thin film 8, 9 . In the PLD technique a large number of processing parameters determine the crystalline quality of the deposited thin film which in turn governs the coercivity mechanism of the studied system.…”