It is a common view among the leading professionals in micro and nanoelectronics that its current explosive development will likely lead to profound paradigm shifts in the near future. A decade ago, at the first Future Trends advanced research workshop, sponsored by NATO, we cried wolf. Today the wolf has come and is at our doorstep: the driving industries of the information economy – from telecommunications, to microprocessors and storage, and other semiconductor-based electronics – are in deep trouble. Is this change of fortune temporary or fundamental? Are the limits technological or rooted in economics? If the problem is economic, what are the plausible scenarios and where are the new areas of opportunity for the future evolution of nanoelectronics? Thus far, information technology has been a great and celebrated success, but it has been a narrow one in that it has confined itself to information processing and transmission, whereas tremendous opportunities in acquiring and executing on information have gone largely untapped for many decades. Perhaps the moment has arrived for nanoelectronics to extend and broaden its scope to rich but under-explored areas, inspired by and interfacing directly with the unique capabilities of biological, biomolecular, superconducting, and nanomechanical systems. The aim our workshop, continuing the tradition started in 1995, is to provide forum for a free-spirited exchange of views among the leading professionals in Industry, Academia, and Government.
Our civilization is destined to be based on electronics. For better or worse. Ever since the invention of the transistor and especially after the advent of integrated circuits, semiconductor devices have kept expanding their role in our life. Electronic circuits entertain us and keep track of our money, they fight our wars and decipher the secret codes of life, and one day, perhaps, they will relieve us from the burden of thinking and making responsible decisions. Inasmuch as that day has not yet arrived, we have to fend for ourselves. The key to success is to have a clear vision of where we are heading in these turbulent times. Identifying the scenario for the future evolution of microelectronics presents a tremendous opportunity for constructive action today. A free-spirited debate between the leading professionals in the Industry, Government, and Academia is the main purpose of the planned Workshop. The celebrated Si technology has known a virtually one-dimensional path of development: reducing the minimal size of lithographic features. This dramatic evolution has both led us to the threshold of nano-technology and at the same brought about doubts regarding future development. Our crystal ball is muddy. This is going to be the nano millennium… but how about femto-electronics? There are clearly physical limits but can we be reasonably sure that electronics will not dip below 1 nm in the next 1000 years?
New electronic materials, most powerful
enabler of new technologies, will naturally be a central theme in the program.
The evolution of semiconductor electronics has always been intimately connected
with advances in material science and technology. Differentiating from usual
materials meetings our workshop will discuss materials prospects and fundamentals
in the context of future technologies.
The first revolution in electronics, which replaced
vacuum tubes with transistors, was based upon doped semiconductors and relied
on newly discovered methods of growing pure crystals. The early semiconductors
could not be properly termed “doped” - they were just dirty. Today, semiconductors
routinely used in devices are cleaner (in terms of the concentration of undesired
foreign particles) than the vacuum of vacuum tubes. Subsequent evolution
of transistor electronics has been associated with the progress in two areas:
(1) miniaturization of device design rules, brought about by advances in
the lithographic resolution and doping by ion implantation, and (2) development
of techniques for layered-crystal growth and selective doping, culminating
in such technologies as MBE and MOCVD, that are capable of monolayer resolution
of doping and chemical composition. Of these two areas, the first has definitely
had a greater impact in the commercial arena, whereas the second has been
mainly setting the stage for the exploration of device physics. These roles
may well be reversed in the future. Development of new and exotic lithographic
techniques with a nanometer resolution will be setting the stage for the
exploration of various physical effects in mesoscopic devices, while epitaxially
grown devices (especially heterojunction transistors integrated with optoelectronic
elements) will be gaining commercial ground. When (and whether) this role
reversal will take place, will be determined perhaps as much by economic as
by technical factors. It is anticipated that the lateral miniaturization progress
may face diminishing returns when the speeds of integrated circuits and the
device packing densities will be limited primarily by the delays and power
dissipation in the interconnection rather than individual transistors. Further
progress may then require circuit operation at cryogenic temperatures or
heavy reliance on optical interconnections. Implementation of the latter within
the context of silicon VLSI may usher in hybrid-material systems with heteroepitaxial
islands of foreign crystals grown on Si substrates. All these anticipated
developments are likely to be heavily dependent on the progress of material
science and techniques for epitaxial growth of semiconductor layers. However
muddy our crystal ball may be regarding the future trends in microelectronics,
one trend appears to be clear: the device designer of tomorrow will be thinking
in terms of multilayer structures defined on an atomic scale.