Block copolymers promise five-fold storage boost

Scientists at the University of Texas at Austin have released details of a new technique for seriously boosting the capacity of hard drive storage systems, offering a claimed five-fold boost over existing technologies.

Developed by a team led by C. Grant Willson, professor of chemistry and biochemistry at the College of Natural Sciences, the system uses block copolymers to bypass the problem of proximity between magnetic dots in hard drives. 'The industry is now at about a terabit of information per square inch,' explained Willson, who co-authored the paper with chemical engineering professor Christopher Ellison and a team of graduate and undergraduate students. 'If we moved the dots much closer together with the current method, they would begin to flip spontaneously now and then, and the archival properties of hard disk drives would be lost. Then you’re in a world of trouble. Can you imagine if one day your bank account info just changed spontaneously?'

The solution lies in the interesting nature of block copolymers: at room temperature, the material is extremely stable - but when heated, it self-assembles into a highly regular pattern of dots or lines. When applied to a surface with etched guideposts, they can form a pattern suitable for use on a hard-drive platter - creating a textured surface that can store significantly more data than a traditional flat magnetic platter.

The concept of directed self-assembly of such materials isn't new, but the team's work concentrated on reducing the time it takes for the block copolymers to form into their finished state. 'I am kind of amazed that our students have been able to do what they’ve done'” claimed Willson. 'When we started, for instance, I was hoping that we could get the processing time under 48 hours. We’re now down to about 30 seconds. I’m not even sure how it is possible to do it that fast. It doesn’t seem reasonable, but once in a while you get lucky.'

The work isn't purely theoretical, either. Storage giant HGST has already expressed interest in applying the block copolymer assembly method to future hard drives, possibly alongside its existing plans to boost capacities by filling drives with helium instead of air. 'The patterns of super small dots can now self-assemble in vertical or perpendicular patterns at smaller dimensions than ever before,' claimed HGST's manager of patterned media technology Thomas Albrecht of the technology. 'That makes them easier to etch into the surface of a master plate for nanoimprinting, which is exactly what we need to make patterned media for higher capacity disk drives.'

The team's work is published in the latest issue of the Science journal. Thus far, however, neither the research team nor HGST has indicated a timescale for bringing the technology to market.