Amorphous NdDyFeCoTi films were prepared by RF magnetron sputtering onto glass substrates at zero bias, low Ar pressure of 3 - 7 mTorr and low input sputtering power of 100 - 300 W. They were overcoated by a SiO2 protective layer. The magnetic and magneto- optical properties of these films were studied by VSM, Kerr hysteresis tracer, Auger electron spectrum, and electron microprobe. The Kerr angle (theta)k of 0.3 degree(s) and the coercive force Hc of 3 - 5 KOe have been found. The stability of the films was examined by exposure in dry air for one month and annealing at 100 - 250 degree(s)C. The coercive force Hc changed with the film thickness. It was found that the preparation conditions had obvious effects on the structure and properties of the film. The Ar pressure and substrate bias voltage affected the microstructure, magneto-optical properties, and the stability. The films prepared under these conditions have dense, smooth, featureless, highly disorder amorphous structure without any obvious void and columnar microstructure. The aging experiment showed that these films had good oxidation and corrosion resistance. The NdDyFeCoTi films prepared under optimal conditions exhibited excellent magneto-optical recording performance with recording laser power of 5 mW and applied magnetic field of 500 Oe.
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