Hard disk media: future problems and possible solutions

While spin valve transducer technology may be extendible beyond the 100 Gbit/in(2) regime, isotropic longitudinal media will show large data retention problems at about 1/3 of this value. We have recently developed a simple model which indicates that while thermal instability issues may appear at different areal densities, they are non-discriminatory as to the magnetic recording modality: longitudinal, perpendicular, magnetooptic, near field, etc. The model indicates that strong orientation of the media tends to abate the onset of the thermal limit. For the past few years we have taken an approach of controlled growth of the magnetic microstructure of thin-film media. This knowledge has lead us to believe that epitaxial growth of multiple thin-film layers on single crystalline Si may provide a pathway to nearly perfect crystallites of various, highly oriented, thin-film textures. Here we provide an overview of the recording system media challenges, which are guiding our media design philosophy, and discuss materials issues and processing techniques for multi-layered thin film material structures which may be used to achieve very high degrees of Go-alloy film orientation. (C) 2000 Published by Elsevier Science Ltd.