Thermal stability of metastable, epitaxial PrCo7films with high energy density

Two series of epitaxial Pr–Co thin films with a nominal composition of Pr 2 Co 17 were grown on Cr buffered MgO(1 1 0) single crystal substrates by pulsed laser deposition, in which the deposition temperature T D and the post annealing temperature T ann were varied. Pr–Co films prepared at different deposition temperatures crystallize in the metastable PrCo 7 structure (TbCu 7 type) for 450 °C ≤ T D ≤ 650 °C. For T D ≤ 600 °C these films exhibit a ( h 0 0) texture, with the c -axis of the Pr–Co grain aligned in the substrate plane along MgO[0 0 1]. However, raising T D to 650 °C, an additional out-of-plane c -axis texture is observed. Post annealing experiments on films, which are deposited at 450 °C to obtain the unique in-plane texture, reveal that crystal structure, texture and also the uniaxial magnetocrystalline anisotropy of the metastable PrCo 7 structure is maintained for annealing temperatures up to 800 °C. The influence of deposition temperature and post annealing temperature on phase stability and extrinsic magnetic properties are discussed.