Magneto-optical properties and stability of GdTbFeCo thin films prepared by RF-magnetron sputtering

Amorphous GdTbFeCo alloy thin films have been deposited onto glass substrates by RF-magnetron sputtering from a mosaic target. The polar Kerr magneto-optical (MO) rotations for GdTbFeCo thin films were measured by using computer controlled rotating analyzer apparatus in applied magnetic fields of up to 6.5 kOe at room temperature and a He-Ne laser wavelength of 633 nm. It was found that as the incident RF power is held constant, the pressure of sputtering gas argon strongly affects the MO properties and stability of GdTbFeCo thin films. The Kerr MO rotation angle is as high as 0.38 degrees for as-deposited GdTbFeCo thin films without a protective layer at an argon pressure of 1 Pa. In this study the obtained correlations of deposition conditions, microstructure, MO property and stability make it possible to choose the optimal RF-magnetron sputtering parameters for fabricating the rare-earth-transition metal alloy thin films with high performances.