Seagate: HAMR time will help us make big HDD capacity jumps

Seagate CEO Dave Mosley told an investment conference this week that he wants to make bigger capacity jumps on hard disk drive developments – and HAMR technology will help the company achieve this. Seagate will move from its first 20TB HAMR technology to a 24TB HDD, missing out a 2TB intermediate step, he said.

Heat-assisted magnetic recording (HAMR) pushes disk drive areal density beyond the limits of current perpendicular magnetic recording (PMR) technology. It uses a more stable, harder-to-change recording medium than PMR, making it possible to write data by heating the bit areas using a laser.


The 20TB drive may cost more to make than non-HAMR 20TB drives because each head must have a laser heating diode.

Dave Mosley.

Seagate aims to spread HAMR technology widely across its disk drive range to amortise expense across a greater number of drives and so lower the per-drive cost, Mosley told the conference.

He said HAMR technology, with its higher density platters, could be used for lower capacity 12TB and 16TB drives, as a way of taking out platters and heads, while offering the same capacity, to cut costs. Mosley said: “If we can save a disk and two heads in a 16, we will look at doing that.”

Western Digital, Seagate’s arch-rival, thinks microwave assisted magnetic recording (MAMR) is a better way to push disk drive capacity levels into 20TB and beyond, partly because drive read/write heads do not require the addition of a laser heating element. However, WD acknowledges it may have to move to HAMR eventually, because the technology increases areal density more than MAMR.

Mosley said: “We know MAMR really well. It’s a viable technology, but it’s, again, a small turn of the crank. What we believe is that HAMR, largely because of the media technology, the ability to store in much, much smaller grain sizes with better signal noise, with much more permanence, we believe that HAMR is the right path.”

And it’s the way to be able to make bigger jumps in capacity than the smaller increments achievable with MAMR. Think about it this way; WD says MAMR knows best while Seagate says HAMR blows are what we need.