The journey to mass production has been extraordinarily difficult – will it be worth it?

Feature Seagate says it has a clear way forward to 100 TB disk drives using 10 TB per platter technology, but HAMR tech is nearly 25 years old and full mass production is still not underway. What has been taking so long?

HAMR (heat-assisted magnetic recording) technology is used to write data to a granular iron platinum medium that can support stable bit storage at more than 1 Tb/in² area density – but only when the bit areas are heated using a laser. That's 3-3.6 TB per platter with Seagate's ten-platter Exos M drives using Mozaic 3+ HAMR technology.

Traditional perpendicular magnetic recording (PMR) uses room-temperature writing and cannot support such extreme areal densities; the bits become unstable. Western Digital has found a way to push PMR's density to ...