August 23, 2006 9:22 AM PDT

A divide over the future of hard drives

Heat or dots? The question is dividing the hard drive industry as it prepares for a major product overhaul.

Perpendicular hard drive technology, which started appearing last year, currently lets manufacturers increase drive density, or the amount of data stored, by around 50 percent annually. But that pace of progress will likely sputter in about four to five years.

To keep progress going, the first disks based on new technology will need to enter the market around 2011. Competitors differ, however, on how and when ideas for revamping drives should become reality.

Seagate Technologies, the world's largest drive maker, wants to first adopt a concept called "heat-assisted magnetic recording." This involves heating microscopic cells on the disk platters as part of the recording process.

Meanwhile, Hitachi Global Storage Technologies, No. 2 in the industry, favors going forward first with something called "patterned media." In this technique, the cells that store data--which now sit next to each other in a continuous film--would be isolated from each other like dots.

Time is of the essence: Five years--from concept to the first finished products that can be shipped to customers--isn't long. Additionally, Flash memory makers assert that their chips will start to displace drives in notebooks over the coming years. Drive makers scoff at the notion, but agree that technological changes need to occur for drives to protect their turf.

"We need to maintain that 40 percent areal-density growth rate, at a minimum, to stay ahead of flash, and we are dang well going to do it," said Mark Kryder, chief technology officer at Seagate.

hard-drive graphic

Eventually, manufacturers will combine heat-assisted and patterned media to produce drives that will be capable of storing 50 to 100 terabits of data per square inch. That's 280 to 560 times more dense than the 178.8 gigabit-per-square-inch drive coming from Toshiba later this year. (A square inch of 100-terabit material could hold as much data as 12,500 pickup trucks filled with books.)

Seagate and Hitachi, as well as other drive makers, are experimenting with both technologies in their labs. Still, the next step is yet to be determined.

"Most people have thought heat assistance probably would be first, but who knows?" said Jim Porter, president of Disk/Trend, which analyzes the disk drive industry. (Click for photos)

The enemy of hard drives is your thermostat. The devices store data in bits, which are microscopic spots on a hard drive platter. The bits themselves are made up of about 50 to 100 cobalt-platinum grains. When the grains get magnetized in a particular direction, the bit represents either a "1" or "0".

To increase the areal density, which is the amount of data a single platter inside a hard drive can hold, engineers have shrunk the size of bits and grains over the years. This has helped PC makers to boost the capacity of hard drives from a few megabytes to more than 100 gigabytes.

Successive years of shrinkage, however, have led to magnetic grains that measure about 8 nanometers long. (A nanometer is a billionth of a meter.)

Reducing the grains further in size could cause them to flip at room temperature and so corrupt the data--an aspect of the "superparamagnetic effect," first identified in the mid-1990s by Stan Charap of Carnegie Mellon University. And cutting back on the number of grains inside each bit, absent further changes, would increase noise and lower reliability.

Drive manufacturers have bought time with perpendicular drives, which stack the bits vertically. But that solution doesn't eliminate the "no more shrinkage" problem.

One or the other
The heat-assisted camp wants to change the grains. Unlike cobalt-platinum grains, iron-platinum grains will not flip at room temperature, Kryder said. To record or erase data, a laser integrated into the drive would heat a particular bit. The data would get recorded or erased, and the bit would quickly cool.

"We'd have to change the (recording) head to add heat, but it's not that big of a deal," Kryder said. Adding a laser wouldn't increase costs much, he noted. More important, the bits could be applied to the platter surfaces through a film, which is how bits are applied today.

Material changes, however, are rarely easy; for example, the switch from aluminum to copper in semiconductors confounded semiconductor makers. For the heat-applied technology, engineers would have to perfect ways to pinpoint the heat from the laser.

"It requires small optical spots. It requires very sharp thermal gradients. It requires new materials," John Best, chief technologist at Hitachi, said, pointing out hurdles in the process.

"You could argue (about) which one's easier to solve, but it looked to us that the practical problems with patterned media meant that we could probably do it first more easily," Best added.

CONTINUED: How patterns are created…
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Spinning drives on the way out
Solid state, non-spinning storage media is the way of the future. Seagate and Hitachi would be well-advised to recognize this trend and plan accordingly. In another 7-10 years spinning HDD will have gone the way of the 8-inch floppy disk.
Posted by Des Alba (68 comments )
Reply Link Flag
Hows that?
I can buy a 200Gb disk for £60 or 1GB for £30.

Static memory devices have a long way to go to catch up with the advantages of hard disks at the moment.

And don't forget that HDs already have built in redundancy in the way of spare sectors per track, spare tracks to replace faulty ones, plus the ability to reformat and ignore bad areas. Add this to the cost per Gb and they're still way ahead in my book.

Of coure thay're far more susceptible to damage in motion etc, so I would expect to see most personal gadgets to go static mem. Not in my PC just yet though.
Posted by pj-mckay (161 comments )
Link Flag
I wonder if any of these technologies will be fault-tolerant
Meaning, I'd rather buy a 400GB harddrive that is only 200GB mirrored internally than have to mirror two separate 200GB harddrives myself. Once a half drive of the 400GB goes bad, though, you could retire it for non-critical tasks such as external storage etc.

In other words ... how do you RAID a laptop harddrive today...? You can't (easily)!
Posted by Fictia (32 comments )
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Fault tollerance
I think the biggest problem is with moving parts and the best way to get rid of that is flash rom. It might be limited now in its compacity, but I can buy a 4 gb SD card for like $60 or so. If you had the size of a 2.5 inch bay to store memory in flash I think you'd be in the range of 100gb or more all without moving parts.
Heck, if you want a "plan b" have the user carry a 2gb USB stick with a stripped down WINXP install. Then make sure the system can boot USB. At least on the road the laptop wouldn't be useless because of a hard drive failure.
Posted by Jakesty (10 comments )
Link Flag
I'll wait
Heating particles? This sounds even dodgier than the DeathStar
which is the only HD I've ever had fail on me.

Think I'll wait for it to prove itself mature first...
Posted by tonyspencer2 (7 comments )
Reply Link Flag
Why not 5-1/4" media?
The access may be slower, but for movies written sequentially or on a defragged drive it seems like it would work. There's plenty of 5-1/4" bays out there for CD/DVD. It seems this would help stave off technology issues too.
Posted by kovacsbv (1 comment )
Reply Link Flag
For speed-Why not flash/HD combo
If speed were the only problem, why not write to flash which then would write to the HD. Of course, God willing it appears with lasers speed may be greatly increased anyway. (<a class="jive-link-external" href="" target="_newWindow"></a>).

If this is the case, wouldn't liquid cooled type cases may be needed or helpful?
Posted by (4 comments )
Reply Link Flag
For speed-Why not flash/HD combo
If speed were the only problem, why not write to flash which then would write to the HD. Of course, God willing it appears with lasers speed may be greatly increased anyway. (<a class="jive-link-external" href="" target="_newWindow"></a>).

If this is the case, wouldn't liquid cooled type cases be needed or helpful?
Posted by (4 comments )
Reply Link Flag
Who would have thought that "no more shrinkage" would be a problem?

- C
Posted by possumdelight (1 comment )
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