Stress related anisotropy studies in DC-magnetron sputtered TbCo and TbFe films

A series of TbCo films and a series of TbFe films were prepared at different deposition powers and Ar sputtering pressures. It was found that anisotropy decreased with an increase of deposition power. Anisotropy also showed a peak within the range of 2.5 to 11.5 mtorr of Ar sputtering pressures. The perpendicular magnetic anisotropies (K/sub u/) of films still attached to their substrates and films removed from their substrates were compared. The percentage change in K/sub u/ which occurred when the film was removed from its substrate was correlated with the rise and fall of perpendicular anisotropy, although changes were also typically large at 2.5 mtorr of Ar sputtering pressure. Changes in K/sub u/ after removal from the substrate were as large as 46% in TbFe films deposited at 2.5 mtorr of Ar sputtering pressure. Larger percentage changes in K/sub u/ were found in DC-magnetron sputtered films than had been reported previously for RF-sputtered TbFe and TbCo films. The films deposited on thick polycarbonate substrates had the largest anisotropy and also suffered the largest percentage change in anisotropy when removed from the substrate.<
>