Study of structural microstructural and magnetic properties of very thin Co50Pt50 films deposited by PLD

Magnetic Co50Pt50 films few nanometers thick have been deposited by Pulsed Laser Deposition on MgO (100) single crystal at a deposition temperature of 600 °C and then annealed “in situ” for different time. A very thin Pt underlayer (< 2 nm) with an incomplete coverage is used as a possible template to favour the growth of isolated grains of the magnetic layer. The correlation between the structural, microstructural and magnetic properties has been studied as a function of the annealing time. In particular, measurements gave evidence of the presence of two competing effects of the annealing treatment: formation of hard fct-CoPt phase and thermal diffusion process between Pt and CoPt layer resulting in a reduction of the crystallographic order.