Nanofabrication and characterisation
We have a growing track record in this area and produce devices for nanoelectronics research at the University and nano and quantum metrology for the National Physical Laboratory.
The majority of the devices and structures are made using optical and e-beam lithography, focused ion beam, and in-situ manipulation of nano and micro-scaled objects. Nanofabrication is quite simply fabrication on a nanometer scale. Likewise nanomanipulation is the manipulation of objects and structures on a similar scale. The reason we do this is to exploit the unique properties that can exist in materials and devices when they are this small.
To give an idea of the scale involved, and using examples from nature, the often quoted human hair is about 50 micrometers in diameter, that is fifty-millionths of a meter, about half that diameter is a grain of pollen from a daisy. A human red blood cell is a little under 10 micrometers in diameter. An E.coli bacterium is two micrometers long, and less than one micrometer in diameter (one millionth of a meter), we commonly work at this scale. Finally a single strand of DNA is about two nanometers in diameter (two billionths of a meter). In our work this is about as small as we go, where we work with carbon nanotubes and other nanowires of similar dimensions.
As a simple example here are two images of the final stages of fabrication of a device for measuring magnetism of nanomagnetic particles less than 100nm in diameter. The device itself is called a SQUID loop (Superconducting QUantum Interfernce Device) and is manufactured using focused ion beam. In the second image we can see that the particle is placed in close proximity to the loop of the device using nanomanipulation. The whole device is subsequently cooled close to absolute zero (less than 5 Kelvin) and measurements can be carried out.