The effect of oxygen as a surfactant on thermal stability in CoFe/Cu multilayers

In this paper, the effect of annealing on the films grown with and without oxygen is likely to be related to the way in which the oxygen acts as a surfactant, which by reducing surface diffusion, leads to layers that are further from equilibrium before annealing. The films deposited in Ar+O/sub 2/ have an enhanced MR ratio. GMR curves for the films after annealing at 300/spl deg/C for 0.5 hours. The annealing has led to a decrease in the GMR ratio, with the decrease being greater for the Ar+O/sub 2/ and b) Ar. For the Ar+O/sub 2/ film, annealing has reduced the saturation magnetisation and increased the proportion of ferromagnetic coupling, which will lead to decrease in MR ratio. The changes to the transport and magnetic properties can be explained by changes to the microstructure during annealing.