Overview

Nanotechnology is a field that has not been clearly defined, and there may not be a single definition that, when taken alone, has enough significance. It may be easier to define what nanotechnology is not, rather than what it is. A working definition will be tackled in the next section, but for now, let us use an exclusion filter to examine MEMS from a nano perspective. About the only thing presently agreed upon is that nanotech materials, structures, and devices do not extend beyond 100 nm or 0.1 ?m maximum dimensions. However, a few have suggested that the nanotechnology working range be stretched all the way up to 500 nm; but that would only add more ambiguity and move nanostructure squarely into the microworld. Although MEMS is often mentioned, and even grouped with nanotechnology, we need to determine if there is a logical basis for inclusion today. We will find that MEMS devices are much too large to be moved from the microworld where they started.

We need to measure some typical MEMS feature sizes against the 0.1- ?m limit our qualification "nanostick." Most of the skillfully crafted MEMS silicon-mechanical machines and such from Sandia National Laboratories are gigantic when scrutinized under the tiny nanotech viewing glass. Gears can easily be 100 ?m in diameter, making them 1000 times too big for the 100-nm (0.1- ?m) ruler. Also keep in mind that the nominal size of a nano object is 50 nm or 0.05