Engineering the 10 TB notebook drive

Engineering the 10 TB notebook drive

Summary: We all take it for granted that disk capacities keep rising, but did you ever wonder why?Disks are way more complex than you knowChips have a lot of brilliant technology, but disk drives are just as complex.


We all take it for granted that disk capacities keep rising, but did you ever wonder why?

Disks are way more complex than you know Chips have a lot of brilliant technology, but disk drives are just as complex. For example, current disks use 50 nanometer (nm) track sizes, equivalent to the 45 nm feature sizes in the very latest chips. And they read and write those tracks while spinning 120 times a second at a 10 nm flying height!

To illustrate this I'm going to focus on a presentation at DISKCON 2007 by longtime Toshiba researcher Dr. Hiroyuki Hieda.

200 Gbit/in2 now Disk platter size is a constant, so drive vendors have to get more bits per square inch. Currently disks are at about 200 Gbit/in2, close to the grain size of the plated metal.

When the grain is the same size as the track, the track starts to bounce around quite a bit, making it difficult to read and write the data.

Engineering the 10 TB notebook drive [image courtesy Toshiba]

10 Tbit/in.2 then Current technology takes drives to the 1 Tbit/in.2 range, or a 1 TB 2.5" drive. Then where do we get the next 10x of drive density?

There are 2 good candidates, HAMR and BPM.

HAMR, BPM or both? Most of the DISKCON engineers agreed that HAMR - Heat Assisted Magnetic Recording - is the leading candidate. HAMR uses a laser to heat the recording media before writing. The makes the spot easier to magnetize and, when cool, makes the data much more stable.

Engineering the 10 TB notebook drive [diagram courtesy Toshiba]

Bit patterned media The other leading contender is BPM - Bit Patterned Media. The dots magnetize as a group so they are more stable and they can be tightly packed for density. Here's a picture of a kind of BPM:

Engineering the 10 TB notebook drive [photo courtesy Hitachi Global Storage Technologies]

This BPM sample is only 300,000,000,000 bits/in2, far short of the goal. Research into the self-assembly - i.e. the spontaneous organization into ordered structures - of polymers has shown that nice regular patterns of the requisite density can be created, but then there is one more problem: how do you get the patterns to line up in circular tracks?

Combine HAMR, BPM and electron-beam lithography HAMR offers magnetic stability at very small feature sizes. BPM provides the tiny features. How do you get them lined up?

E-beam lithography. Often hailed as the next step in chip manufacturing, but avoided because of cost and complexity, e-beams enable much smaller feature sizes than visible or deep ultraviolet light. The problem for chip vendors is that e-beams are highly focused and slow to scan across a chip's mask. Light is much faster.

E-beams are viable for disks though. The e-beam creates a master that stamps out millions of disk platters with nano-scale features. That's how CDs and DVDs are manufactured today, except for the e-beam feature sizes.

Prototype self-assembled BPM + e-beamed groove If current thinking holds, the 10 TB notebook drive will be built using HAMR and self-assembled BPM on disk platters stamped out by e-beamed masters. Here's what a laboratory prototype looks like, up close and personal:

Engineering the 10 TB notebook drive. [atomic force microscopy image courtesy Toshiba]

The Storage Bits take Disk capacities double about every 2 years, so the 10 TB 2.5" drive is about 10 years away. While I've focused on the problems of the physical media, disk storage researchers are banging away on a dozen major research areas - including signal processing, servos and heads - to make higher capacity storage possible.

I'd like to see the disk vendors do a better job of communicating the incredible work they are doing. Storage is the hardest part of modern computing, disk vendors are doing the heavy lifting, and they get very little credit for all their hard work.

That is just wrong. Disk technology is even more amazing than chip technology, but the engineering-driven disk companies are wallflowers at the big technology dance.

Comments welcome, as always.

Topics: Hardware, CXO, Enterprise Software, Laptops, Mobility, Storage

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  • Every 2 years?

    "Disk capacities double about every 2 years"

    It's possible you're right but I just got my 300 GB drive because prices dropped when the 500 GB drive came out about 6 months later a 1 TB drive came out. That was over a span of about 6 months.

    There did appear to be a lull. Like space jumped and to the 100 GB range and that seem to hover between 100 GB and 250 GB for some time. Then BAM 500 GB appears followed by 1 TB shortly after.

    I just don't remember 500 GB drives existing 2 years ago. Could be they did and were so expensive you just avoided even looking at them.
    • 500 gig drives were around in 2005...

      ... but they also cost almost $1 or more per gig. Prices have come down to a point where you may be paying anywhere from $ .25 to $ .35 per gig. EIDE drives are at an all time low as the SATA and SATA II drives begin to gain popularity and market share. EIDE (PATA) drives of capacities up to 500 gigs can be had for less than $200 for the astute and patient shopper.

      I would like to see the cost for external NAS and backup appliances drop along with the price of the drives they use. After all, if everything is now SATA and SATA II drives from the OEMs, why should we still pay premium prices for devices using PATA drives?
      Confused by religion
      • Minor corrections to your prices ...

        500GB SATA Drives are available online for $100, and 750GB drives are $190 according to Sharky's August price survey. You'll pay anywhere from %50-%100 more if you buy retail, but I just consider that a form of stupidity tax ...

        I agree with your point about NAS and backup appliances, but you can find some useful bare units like the Linksys or D-Link units for under $200 without drives. I've got a 1TB 2-drive NAS from Maxtor that also serves as a print server for my HP laser, and it cost $400 complete.
        terry flores
        • I admit I am drive full right now...

          ...and have hot looked at prices in about 5 or 6 months. If SATA and SATA II drives have dropped that much in price, we should see a savings in external NAS and backup drives that use this type of drive. And that should mean substantially lower prices for external HAS and backup drives using the outdated (and soon to be obsolete?) PATA drives.

          C'mon retailers, step up and pass the savings along!
          Confused by religion
    • Disk capacities & number of platters

      It's quite possible the "capacity doubles every 2 years" statement is correct - when you look at the capacity of individual platters. Early versions of high-capacity drives tend to have multiple platters. As the technology matures and the capacity of each platter increases, the same overall capacity can be achieved with fewer platters and so the price comes down.
  • Let's See Something New

    The notion of a hard drive is antiquated. Too much to go wrong, with all of those moving parts. Too slow, too.

    I'd like to see a bit less research into expanding hard drive capacity and a bit more research into solid-state storage systems.
  • Maybe it's time to break out the old 5.25" disks?

    I seem to recall some discussion about this a few months ago, but the details are hazy. Given the data density on a modern hard drive, what would happen if someone produced a hard drive designed like a 3.5" drive but in a 5.25" form-factor? Would we have staggeringly large amounts of data storage coupled with excruciatingly slow data access? Would the angular velocity at the outside of the disk approach the speed of light, with a concurrent increase in mass? And just how far away are we from quanta-based photonic storage devices?

    Anyone else here remember 8"-based floppies?
    • 8" floppies

      I sure do remember the 8" - based floppies. Used them in the DEC PDP-11 machines. Still have one kicking around.
    • Maybe it's time to break out the old 5.25" disks?

      A 5.25" drive could have about 2.25 times as much capacity as a 3.5" drive using the same technology.
      The average seek time would be 50% longer, as would be the tengential speed at the rim, very far from relativistic speed. This result in an equivalent increase in the potential data rate on those outer tracks.
      This would be good for long term storage, and any application where seek time is secondary.
      • 2.25 times the capacity?!

        Well, fry me up and call me cornbread! So, instead of the 1 Terabyte (1000Gb) hard drives we have now, we could have 2.25Tb (2250Gb) hard drives? That would make a really sweet backup drive.

        If you can partition the drive so any programs you need would be on the outer rim of the drive and the data closer to the center, you probably wouldn't notice the slower access times of your data. Include a hefty cache and an intelligent scheme for reading serial data (i.e., media files) into the cache before its needed, and you've got yourself one fantastic media center!

        Put 5 of these puppies into a RAID 5 array, and you've got 1 PETABYTE (1,000,000GB!) of storage! Wow, that might take me, what, three or four months to fill up?

        I'd like to see a drive manufacturer make such a monster just to do it.
        • PUN ALERT!!!

          [i]Put 5 of these puppies into a RAID 5 array, and you've got 1 PETABYTE (1,000,000GB!) of storage! Wow, that might take me, what, three or four months to fill up?[/i]

          I was talking about this with some of my co-workers, talking about what we would store on a 1 Petabyte storage space. There were the usual suspects: ripped DVDs, home movies, every album or CD you ever listened to as a teen-ager (the fact that I included "album" and "CD" tells you the age range of the participants), family photos, including scanned copies of all the photos every one of your grandparents, aunts, and uncles ever took.

          Then one guy said, "Wow! Just think of all the porn you could store!" Suddenly, it hit me: If I truly want one of these huge storage systems just to be able to [b]have[/b] 1 Petabyte of storage space at my fingertips, does that make me...

          ... a Peta-phile?
      • As a tape replacement?

        While I doubt the equipment exists to build 5.25" disks any longer - the drive folks
        aren't very sentimental - if you look at the cost of a modern tape cartridge and a far
        down the learning curve disk, they aren't much different. And the disk gives you
        random access.

        R Harris
        • Re. As a tape replacement?

          [i]While I doubt the equipment exists to build 5.25" disks any longer [/i]

          Well I doubt the equipment needed to build an Apollo spacecraft exists anymore, either, but I have no doubt that replacement equipment (that would be faster, lighter, etc.) could be quickly made if necessary.

          [b][i]The problem isn't that we shot ourselves in the foot. It's how quickly we reloaded and fired again.[/b][/i]
          • Can we really ?

            Its an interesting idea, that can be 15Tb/side. but can the plating's grain size be kept to less than 1/40 micon (1/1m inch) on a polymer substrate ? I wonder how much surface roughness the head can handle ? Hmmmm.

          • That is the point of patterned media

            Make a regular pattern and grain size goes away.

            R Harris
    • RE: Engineering the 10 TB notebook drive

      How about this. I have the platter out of an old HD that had fixed heads. The platter is made of ceramic with what looks like brown iron oxide coating (like a cassette tape). It is about 1/2" thick and 8" across. I wonder what sort of capacity it had?
  • Where can I find 720 KB floppy disks?

    I just bought a 10 year old but still very viable Kurzweil synth with one of those.

    Why is it that as science gets more marvellous, the arts get more dumbed down and stupid (yes, that was a direct stab at pathetic hip hop and (C)rap)? Art is moving in the opposite direction of science!

    • Tape the hole

      I think you can try to use a 1.44mb disk. Not sure if the magnetics will play. Try placing tape (black) over the density hole in the upper left corner. I used to have a punch that put holes in 720K disks to make them 1.44mb.
  • RE: Engineering the 10 TB notebook drive

    Don't forget the idea is to store data. Be it with a hd, a flash card or holographic memory systems, it's all about storing data. People developping hd are entitled to as much as respect as people developping the next generation of storage systems.
  • COOL