2005 Volume 5 Issue 2 Pages 69-72
We studied the magnetic properties of TbFeCo thin film sputtered onto TiN underlayer with different surface morphologies resulted from different thicknesses. According to the results of atomic force microscopy, the surface roughness of TiN film is increased as the film thickness increased. Initially the coercivity is increased sharply from about 2 kOe to 6 kOe for an increase of underlayer thickness to 60 nm then the increasing rate of coercivity becomes very slow. At about threefold increase in the coercivity is thought to be due to the enhancement of domain wall pinning effects caused by an increase of surface roughness in the TiN underlayer. For the underlayer thickness of more than 60 nm, the M-H loop has been changed from rectangular to nonrectangular resulting remanent squareness ratio of less than unity. There is no significant effect of TiN underlayer thickness on the saturation magnetization has been observed.
