A team of researchers at the University of Texas is working on a novel design that could circumvent some of the pressing limitations of current data storage technology and open the door to a new generation of very high-density, cheap and reliable hard disk drives.
Since disk drives were first introduced in the mid 50s, memory storage density has increased by nine orders of magnitude – a staggering pace that rivals the exponential growth in performance of integrated circuits. Should the current technological and pricing trends continue, we will see 2.5-inch 40-terabyte drives sell for as little as US$40 by the end of the decade.
But the road to cheaper data storage won't be completely straightforward. In hard disk drives, bits are stored as individual magnetic dots laid onto a metal surface: the closer together the dots, the higher the storage density. These days, we can cram as many as one trillion dots (128 GB of data) on a single square inch of metal. However, placing the dots any closer than that would cause magnetic interference from neighboring dots that will randomly flip bits and corrupt the data irreparably.
Researchers at the University of Texas have come up with a solution to the problem: they were able to produce nanoscale self-assembling dots, and managed to work around the limitations that hamper traditional designs. In doing so, they laid the foundations for the production of cheap, reliable hard drives with record storage density.
The key to this development was the synthesis of block copolymers, a material that can quickly self-assemble into dots that are less than 10 nanometers in size – the smallest ever created.
Remarkably, the polymer will follow any pattern etched into the surface on which it is deposited. This behavior lends itself especially well to manufacturing hard disk drives: when deposited on a properly prepared metal substrate, the polymer will conform itself and produce the required dot design with a very high degree of accuracy, and in a matter of just a few seconds.
Elegant as it is, this solution would be useless without a way to place the dots stand closer than normal and still preserve data integrity – and, fortunately, the researchers have found a way to do just that.
In fact, the researchers found that whenever the dots are isolated and have no magnetic material between them, they don't suffer from the destabilization problem seen with other designs. A special coating is therefore employed to cover the metallic disk and ensure that the data is kept safe.
The team is now working with Hitachi Global Storage Technologies to try and adapt this technology to their products and integrate it into a mainstream manufacturing process.
A paper detailing the study was published on the journal Science.
Source: University of Texas
