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A nanoscale device can be defined as a device in which nanoscale components play a critical role in functionality. Nanoscale devices may be the result of top-down or bottom-up processing.

Top-down processing refers to miniaturization of macroscale devices. The semiconductor and recording media industries currently produce hundreds of billions of dollars of products containing nanoscale devices resulting from top-down processing. Field effect transistors (FET) and read-heads based on the gigantic magnetoresistance effect (GMR) are a couple of examples.

Bottom-up processing refers to constructing devices starting at the molecular level. For example, in the field of molecular electronics, Institute researchers are looking to individual organic molecules, carbon nanotubes, or boron-doped silicon nanowires configured to provide logic states for either memory or computing. NEMS (nano-electromechanical systems) contain nanoscale components that can act as actuators, sensors, or very high-speed optomechanical switches. Switches have been developed with a bistable carbon nanotube in which a cantilevered, multi-walled carbon nanotube is clamped to a top electrode and actuated through a bottom electrode. This novel arrangement forms a feedback-controlled switch in a circuit with a resistor and a voltage source - with potential applications including ultrasonic wave detection, gap sensing, memory elements, and logic devices. The remarkably small inertia of nanoscale objects means that it is possible to consider the nanoscale equivalent of the Babbage difference engine where tiny mechanical switches perform calculations at remarkably high speeds. Individual molecules can act as switches or as memory elements. Such structures represent a very substantial advance in the miniaturization of electronics, but to date such structures are difficult to reproduce, and subject to large fluctuations in their electronic performance. Another interesting example is the revival of the vacuum diode (and triode) that had previously been supplanted by the silicon based solid-state devices. The field of vacuum microelectronics has thus been re-vitalized by the emergence of nanoscale field emitters that, due to their high aspect ratio and small size, can emit electrons directly into a vacuum at very low applied voltages. This offers the possibility of new forms of lighting and flat panel displays with high brightness and exceptionally low energy cost. In order to test and verify performance of nanoscale devices, additional devices must be invented that will be constructed from other nanoscale components. The Lilliputian world requires Lilliputians to do the testing!

Significant work in “bottom-up” (or hybrid "bottom up/top down" methods) assembly has been done in 2-D that could lead the way to constructing 3-D nanoscale devices. Applications of nano-writing methods via dip-pen nanolithography, nano fountain pens, or nanoimprint lithography (all developed by Institute researchers) offer the potential for achieving very high-density assays. Each element “pixel” in the array may act as a read out, potentially enabling hand held “point of care” analyses that are currently not possible. Thus, the function of the macroscale point of care device is based on the rudimentary nanoscale individual pixels. Opportunities for invention and “enabling devices” abound in biomedical R&D, such as nanoengineered patch clamp devices, nanoelectrodes for neuroscience research, nanopipettes for direct injection or extraction of material into organelles in cells, and many more. Due to the very small size and the potential for remarkably low cost of certain types of nanoscale devices, other promising applications as yet unforeseen may exist, such as incorporating nanoscale devices in complex systems (i.e. smart materials, embedded in living systems) for reporting functions and control.