ULTRA HIGH-DENSITY MEDIA - GIGABIT AND BEYOND

Recent high areal density demonstrations in the gigabit/in2 regime have shown a path toward high capacity small drives in the future. We will review recent progress made in understanding the relationship between the media magnetic properties and recording characteristics such as linear resolution, transition noise and overwrite. For high linear resolution media, the coercivity is now attainable in the 2000 - 3000 Oe regime depending on the alloy, underlayer and other process parameters such as substrate temperature and bias. Various noise reduction schemes have been developed in recent years which are based on the decoupling of exchange interactions between magnetic grains or between multiple magnetic layers. As the bit cell size is further reduced in the gigabit/in2 regime one of the main challenges will be to retain a high coercivity with decreasing grain size of the magnetic film.