Microsystem & MEMS technology enables Nanotechnology, and there are many MEMS fabrication technologies being scaled down to produce nanoscale devices. Perhaps the best example of this is the micro-tip field emitter. Essentially a microscopic electron gun, consisting of a conical field emitter with a tip radius of 10 - 20 nm.
Currently ANSYS Multiphysics addresses some nanotechnology simulation requirements covering ion optics, and electrostatic calculations associated with field emission tips and carbon nanotube structures.
The ion optics capability is a post-processing feature where charged particles can be introduced into computed electromagnetic fields and their path traced with "streamline" graphics. The user can control the "history" of the charged particle, changing its mass and or charge to simulate for example, fragmentation. Currently effects such as "space charge" are not incorporated, since each trajectory is computed independently.
At the nanometer scale the bulk material models used by finite element tools break down as quantum mechanical effects become dominant, however our recent introduction of highly customizable, user programmable material models may help to address the finite element analysis of some nano-systems. Note that some of our users have made reasonable approximations to polycrystalline grains in surface micromachined parts using this approach (MSM2000).
After nano, the next SI prefixes are Pico, Femto, Atto, Zepto and Yocto. These prefixes venture into the range of subatomic particle size!
In future keep a look out for:
"Pico - Pico" doesn't quite have the same ring as "Nano-Nano" though!