The coming world of nano- and pico-technology
10/01/2001
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The semiconductor industry is the most remarkable in the history of modern mankind. The exponential progress represented by following Moore's Law — doubling the number of devices per chip area every 18 months, with the dramatic cost/performance improvements this entails — has opened vast new application areas. Progress has been so rapid that our skill at putting all this technology to work has been severely challenged. But system designers and application developers will figure it out, and the results will transform our entire society and its infrastructure.
Meanwhile, every few years or so it seems, the New York Times and other popular media run stories about "The End of Moore's Law." Even as the reporters cite how we are running into the stops in keeping the shrink going for the next few generations, they always add side comments about work on solutions to get around seemingly insurmountable barriers — and the needed innovations have always materialized. Until recently, features were shrunk using the same basic materials, with perhaps some process advances such as rapid thermal processing and chemical mechanical planarization. Today, to continue shrinking features while also dramatically boosting performance, the materials set is changing. Even with added challenges, the industry has actually begun to push ahead of Moore's Law projections.
The question remains, though: Are we running into the end of Moore's Law? In truth, Gordon Moore's observation back in 1965 was not really a "law;" it was his prediction that competitive forces would continue to push IC progress at the same rate into the future. Even Dr. Moore has expressed amazement that his semi-log projection has held true (at least approximately) for nearly four decades, allowing his prediction to take on the aura of a "Law." Progress looks solid until 2005, the 40th anniversary for Moore's Law, and laboratory work suggests the shrink can continue apace into the next decade. But then it begins to get dicey. With red brick walls springing up everywhere over the next 5
While physics sometimes presents barriers, remarkably, materials science is showing us that quantum quirks also may offer intriguing solutions. Some quantum devices being studied actually align themselves automatically into regular arrays of potential devices as they are deposited. The Materials Research Society has made Self Assembly the main theme for its fall meeting in Boston.
Researchers at laboratories of IBM and Hewlett-Packard, among others, have shown the possibility of making switching devices from organic polymers, or out of a few atoms within carbon nanotubes. To perform the tasks of electronic systems, three-terminal transistor-like devices that can amplify will be needed to supplement these two-terminal structures that can only switch states. In systems of the future, light pulses may be combined with electronics, all within the same chip. The organic light emitting diodes (OLEDs) now exciting display developers may offer technology that could also enter into future IC architectures. All-polymer transistor circuits are already being squirted onto substrates using ink-jet printer heads by Philips Research Labs and others. Some pico-devices have demonstrated capabilities for multilevel logic, enabling systems that go beyond 1 and 0 to multiple states within the same pico-device, offering another route to putting far more processing power into the same chip area.
To make picotechnology practical, there also needs to be interconnects that can link a total system, and contacts that can bring signals from the pico-device world into practical readouts or actuators. Of course, all these exotic technologies remain far from practical application, but the steady stream of functional demonstrations, and experiments with new types of fabrication for pico-devices, brings hope for keeping Moore's Law going beyond the limits of silicon CMOS.
Beyond conventional electronics, another world of emerging technology — the revolution of genome exploration — may well help us discover how to build and operate practical picosystems. Finding ways to structure amino acid chains into meaningful strings like those found in the genes of living creatures, and also to rapidly analyze these structures, is creating tools that may prove valuable in developing production methods for molecular devices of the future. Nature has developed cell factories by using RNA templates to accurately copy and transcribe stretches of DNA in an endless process of cell division and duplication. This self-replication technique might suggest how to develop production methods for molecular devices in some future exotic device technologies.
So far, it has been a breathtaking adventure. There's no reason it couldn't keep right on going, and become even more exciting, for another 40 years.
Robert Haavind
Editor in Chief