Future Options for HDD Storage

The HDD industry is at a critical technology cross roads and it is paramount that we quickly establish comprehensive paths to push beyond the superparamagnetic limit. Several promising technology options have been explored to increase the areal density beyond the limit such as bit patterned magnetic recording (BPMR), heat assisted magnetic recording (HAMR), and microwave assisted magnetic recording (MAMR). In addition to these three technology options, there is recent interest in a fourth approach that has the advantage of staying with a relatively conventional perpendicular medium and head. This combines shingled write recording (SWR) and/or 2-D read back and signal processing. Either technique can be used separately to give large gains and the combination of the two, which is referred to as 2-D magnetic recording (TDMR), promises particularly large gains. Recording with energy assist on BPM or 2-D signal processing will enable the areal density beyond around 5 Tb/in2, although none of them have shown a clear problem-free solution. Precompetitive research projects and programs have recently started targeting 2 Tb/in2 by 2010 for SRC, 5 Tb/in2 by 2013 for NEDO, and 10 Tb/in2 by 2015 for INSIC. This paper reviews the technology options ahead, and the pros & cons for each option. We include a brief introduction to SWR and TDMR.