Early Nano Technologists

The American Physical Society held its 1959 annual meeting at the California Institute of Technology. Scheduled to speak was a man who would win the 1965 Nobel physics prize for his historic work in quantum electrodynamics. Still later he would serve on a Presidential Commission and find the fault in the Challenger disaster in a disturbingly brief period of time. In 1959 however, he spoke of other work that may be even more important. In his talk entitled There's Plenty of Room at the Bottom, physicist Richard Feynman (1961) proposed a simple and straightforward strategy for constructing useful structures ranging in size down to the atomic scale! He suggested using machine tools to make many more sets of much smaller machine tools, which would in turn make many times that number of other, even smaller machine tools, and so on. At the lowest level, he noted the possibility of mechanically assembling molecules, an atom at a time.

Feynman proposed the construction of nanomachines, nanotools, tiny computers, molecular scale robots, new materials and other exotic products which would have far reaching applications and benefits. Considering the relevance of nanotechnology to living molecules, Feynman (1961) noted,

A biological system can be exceedingly small ... . Consider the possibility that we too can make a thing very small, which does what we want-that we can manufacture an object that maneuvers at that level!

Machines able to directly manipulate matter on the submicron to nanometer size scale are referred to as "Feynman Machines" (FMs). The only existing FMs currently known are biological, however computer controlled or teleoperated FMs may in the future implement a broad range of nanotech applications.

Following Feynman's lead, other scientists delved into nanotechnology. Von Hippel (1962) predicted dramatic material science possibilities if new advances in "molecular designing" and "molecular engineering" of materials could be achieved. Noting the eventual possibility for repairing human tissue (molecule by molecule if necessary) for life extension, Ettinger (1964) suggested repair machinery for modification and interaction with existing organisms; later he proposed development of nanorobotics. Ettinger envisioned nanoscale scavenger and guardian organisms designed to emulate and surpass the actions of white blood cells which might hunt down and clean out hostile or damaging invaders (Ettinger, 1972). Such nanorobots might be useful for fighting AIDS or cancer, excavating blocked blood vessels, or straightening neurofibrillary tangles in senile neurons.

Shoulders (1965) reported the actual operation of micromanipulators able to position tiny items with 10 nm accuracy while under direct observar tion by field ion microscopy. Ellis (1962). also developed similar (but much larger)

micromanipulators and proposed the construction of "microteleoperators": remote controlled nanodevices! Drexler (1981, 1986) has described some advantages and hypothetical dangers of nanotechnology. Capabilities for atom-by-atom assembly and nanoengineering could lead to new materials and pathways (Feynman, 1961). One such material is "diamond-like carbon" films which are "transparent, insulating, chemically inert, have a high dielectric strength, good adhesion and are relatively hard" (Aisenberg, 1984). Drexler suggests that rotary hammers a few molecules long might be used to hit carbon atoms in graphite at just the right angle and force to create lightweight diamond films and fibers useful in a variety of material applications. Drexler warns of two Frankenstein aspects to nanotechnology: nanosensor surveillance, and uncontrolled replication of nanodevices with consumption of biosphere resources. However, the existing, dramatic developments in microsensor technology and microelectronics render worries about nanosensor surveillance superfluous (Schneiker, 1986). Schneiker also discounts Drexler's extreme "end of the world" worries about nanoreplicators, pointing out that the Feynman machine (top-down) approach to nanotechnology, microreplicators and other factors obviate the problem. Nonetheless, like genetic engineering, nuclear power, the automobile, and junk food, nanotechnology may well be a "double edged sword" which demands responsible management.

Potential benefits from nanotechnology attainable in perhaps a decade or two might include (Schneiker, 1986):

... vastly faster, much more powerful and numerous computers with extremely large capacity memories, ultrastrong composite materials, greatly improved scientific instrumentation, microscopic mobile robots, and automated flexible manufacturing systems, replicating systems, and achieving the practical miniaturization limits and maximum performance in virtually every area of technology.

Despite these lofty hopes and predictions, nanotechnology and molecular computing have remained mere dreams. Obstacles to their implementation center on the absence of available Feynman machines. A feasible solution has been advanced by a present day nanotechnologist whose contributions may eventually eclipse all others. Conrad Schneiker (1986) may have found the bridge to the nanoscale. He predicts that atomic level manipulative capabilities embodied in a 1981 invention, the scanning tunneling microscope (STM), can implement nanoscale Feynman machines (Hansma and Tersoff, 1987). Schneiker had noted that even without the STM, and before its invention, silicon micromechanics combined with other technologies could have been used. Not content with two approaches, he also proposed another route based on augmented machine tool technology originally developed for single crystal diamond machinery. But STMs are much more convenient and much less expensive.

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