Effect of sputtering power on the magnetic properties of amorphous perpendicular TbFeCo films

A series of amorphous perpendicular TbFeCo films are sputtered using a composite target. The magnetic properties of the TbFeCo films are found to strongly be influenced by sputtering power. The above-RT magnetic compensation point in the films sputtered at high powers is revealed by thermomagnetic measurements. With increasing the power the compensation point shifts considerably towards higher temperature, while only a slight reduction in the Curie temperature occurs. The coercivity is found to initially increase with the power and then falls, which is in accordance with film composition moving from FeCo-rich to Tb-rich side. This can be well explained by the sputtering yield of Tb, which increases faster than FeCo atoms with the power during the sputtering. Our results show a convenient way to adjust the coercivity of the films by modifying the Tb-to-FeCo ratio using the sputtering power. •Magnetic properties of TbFeCo are found to be strongly related to the sputtering power.•The above-RT magnetic compensation point is revealed in the high-power sputtered films.•The compensation point is observed to shift considerably towards high temperature with increasing the power.•The change in coercivity is in accordance with the change in film composition.•The sputtering power can be used to adjust the magnetic properties of TbFeCo films.