Gadget makers have for decades relied on ever-shrinking microchips to make more portable, yet more powerful, devices. But as the components used to make these chips become smaller, with widths measured in dozens rather than hundreds of nanometers, they become increasingly more difficult to assemble.
Since microchips are the engines performing the logic functions that make computers, cell phones and countless other electronic gadgets run, technology makers like IBM have been looking to pack more transistors closer together in smaller spaces.
Now comes a potential solution. IBM Research and the California Institute of Technology researchers say they may have found a way to control the placement of silicon nanowires, carbon nanotubes and other tiny components on microchips through the use of synthetic DNA and tiny lithographic templates. The scientists used the DNA molecules to function as scaffolding, to help deposit millions of nanosize particles in precise patterns, according to a study to be published in the September issue of Nature Nanotechnology . ( Scientific American is part of the Nature Publishing Group). The templates help the nanoparticles hold their shape.
When the DNA is folded into certain origami-like structures, it might even possible to place components six nanometers apart (even thinner than a cell membrane), whereas conventional semiconductor fabrication techniques are struggling to reach placement closer than 22 nanometers (a number thought to be out of reach just a few years ago).
DNA origami is created by using hundreds of short DNA strands (also called "staples") to fold much longer genetic ribbons into nanoscale shapes and patterns. Some researchers think that DNA origami proves microscopic material can be controlled to form specific objects, including smaller circuits.
Technology makers are looking for ways to keep pace with Moore's law, an observation by Intel co-founder Gordon Moore in 1965 that the number of transistors placed on an integrated circuit doubles every two years. The cost to continually shrink electronic components to improve performance is a limiting factor in keeping pace with Moore's law and "a concern across the semiconductor industry," Spike Narayan, manager for science and technology at IBM's Almaden Research Center in San Jose, Calif., said in a prepared statement. IBM seeks better ways to assemble microchip components at the nanoscale without the need to replace existing chip-making technology.
There is a downside to this in that smaller components create more complexity and require some way of dissipating heat before it destroys the surrounding circuitry.
Of course, IBM and other tech companies have some time to work this out: the company says it will be at least a decade before its DNA microchips are ready for the market, according to the Guardian UK .
Image of triangular DNA origami adhering to a template © IBM