Analysis of microstructures for Co/Pd multilayer perpendicular magnetic recording media with carbon underlayer

The effect of amorphous carbon underlayer thickness on the microstructure o f the CO/Pd multilayer perpendicular magnetic recording media was investiga ted. From the magnetic force microscopy observation in the AC-demagnetized state of the Co/Pd multilayer media, the magnetic cluster size was observed to effectively decrease with an increase in carbon underlayer thickness, w here the higher coercivity and the higher SIN ratio of the Co/Pd multilayer media were obtained with the thicker underlayer. Furthermore, the distribu tion of [111] orientation of FCC-Pd became broader, and the grain size decr eased with an increase in the carbon underlayer thickness. These effects ca used the magnetic exchange decoupling of Co/Pd multilayer media. We suggest ed that the change of microstructure was directly related to the surface ro ughness of the amorphous carbon underlayer. (C) 2001 Elsevier Science B.V. All rights reserved.