Researchers unravel the secret to making cheap, high-density data storage
October 11, 2012
Magnetic media with (right) and without (left) a smoothing layer (credit: Shreya Kundu, et al./Scientific Reports)
Researchers from A*STAR’s Institute of Materials Research and Engineering (IMRE) and the National University of Singapore (NUS) have discovered that an ultra-smooth surface is the key factor for “self-assembly” — a cheap, high-volume, high-density patterning technique for data storage.
This technique allows manufacturers to use the method for data storage on a variety of different surfaces. This discovery paves the way for the development of next-generation data storage devices, with capacities of up to 10 Terabits per square inch, which could lead to significantly greater storage on much smaller data devices.
The “self-assembly” technique is one of the simplest and cheapest high-volume methods for creating uniform, densely-packed nanostructures that could potentially help store data.
Self-assembly is one of the leading candidates for large scale nanofabrication at very high pattern densities. One of its most obvious applications will be in the field of bit-patterned media for the hard disk industry.
It is widely used in research and is gaining acceptance in industry as a practical lithographic tool for sub-100 nm, low-cost, large area patterning. However, attempts to employ self-assembly on different surface types, such as magnetic media used for data storage, have shown varying and erratic results to date. This phenomenon has continued to puzzle industry researchers and scientists globally.
Researchers from A*STAR’s IMRE and NUS have now solved this mystery and identified that the smoother the surface, the more efficient the self-assembly of nanostructures will be. This breakthrough allows the method to be used on more surfaces and reduce the number of defects in an industrial setting. The more densely packed the structures are in a given area, the higher the amount of data that can be stored.
The team discovered that a height of 5 angstroms (the width of about 5 atoms) RMS (root mean square) roughness was the maximum surface roughness allowed for successful self-assembly of dots, which could eventually be used in making high-density data storage.
“If we want large scale, large area nanopatterning using very affordable self-assembly, the surface needs to be extremely smooth so that we can achieve efficient, successful self-assembly with lower incidences of defects.”
The discovery was recently published in Scientific Reports, an open access journal from Nature.
This research is supported by the National Research Foundation Singapore under its “Frontier in magnetic recording research: Vision for 10 terabits per square inch” programme (NRF-CRP 002-097 NRF-08) and administered by A*STAR’s IMRE.
Comments (7)
by Jos Smit
Looking at the comments above it seems I’m the only person that has no clue what this article is about. I don’t see how self-assembly has anything to do with data storage. And it’s also unclear to me how a smooth surface is the key factor for this. The third and fourth paragraph gives me some clues, but not even close to enough. Usually I mostly understand articles on this web site.
by asiwel
If an extremely smooth working surface is needed, it would seem that the very first “nanoassembly” problem would be to take a reasonably rough surface and “nano-coat” it such that the result, on one side – the exposed side -, is extremely even. Then build subsequent structures on that surface. Proteins that attach and then fold just enough to line up along the outer surface might be an example coating material. Of course, I am “out of my depth” here but it seems there are also ways of manipulating the physical size of molecules, the “size” of atoms and orbital radii of layers of electrons, etc., such that the surface roughness could be filled in smoothly at the nano-level.
by Editor
Yes, they use a coating called TranSpin (as explained in the open-access paper at http://dx.doi.org/10.1038/srep00617)
by asiwel
Reading the open access paper, it looks like the TranSpin coating worked pretty well on surfaces that were pretty smooth to begin with. But even 5 coats of Transpin were eventually overcome by increasing surface roughness >5A. I thought it was pretty interesting how they set up the test surfaces’ roughness, beginning with glass (polished silcon or crystal) platforms and using magnetron sputtering to create other surfaces.
by Gorden Russell
Just imagine what it will be like for us if Singapore develops the self-assembling photovoltaic carbon nanocells first. We will become a third world nation. They will leave us behind in the dust.
by asiwel
First of all, for A*STAR, it is interesting that “Peter Hart, Nils Nilsson and Bertram Raphael of Stanford Research Institute (now SRI International) first described the algorithm in 1968″ (Wikipedia). So we invented that. I looked up the A*STAR agency in Singapore which “oversees 14 biomedical sciences and physical sciences and engineering research institutes, and six consortia & centres, located in Biopolis and Fusionopolis as well as their immediate vicinity” (their website). IT really does look like a very impressive organization with a distinguished Board of Directors, a full range of international credentials, and lots of folks trained in the West. Still the U.S. leads in photovoltaic research, for the time being anyway, and I certainly hope that we as a nation will “stay ahead” in this particular game!
by Dan Symes
It’s irrelevant who develops products first. It’s a global economy. The inventor/developer will either sell the product or the rights to others. Global product development benefits the whole globe.