High post-annealing stability in [Pt/Co] multilayers

The [Pt/Co] multilayers with a very thin Pt layer of 0.2 nm are presented that exhibit strong perpendicular magnetic anisotropy (PMA) even after annealing up to 500 °C. The observed post-annealing stability is in significant contrast to that previously shown for conventional multilayers with a thicker Pt layer than Co, where good PMA properties are obtained in the as-deposited state but they deteriorate significantly at moderate annealing temperatures below ∼300 °C. The reason for the high post-annealing stability is a low level of intermixing during sputtering due to the very thin Pt layer.