David Cox, a scientist in the Quantum Detection group at the National Physical Laboratory in the UK, built the world's tiniest snowman using nanofabrication techniques. The NPL snowman is 10 microns across, 1/5th the width of a human hair.
The snowman was made from two tin beads used to calibrate electron microscope astigmatism. The eyes and smile were milled using a focused ion beam, and the nose, which is under 1 µm wide (or 0.001 mm), is ion beam deposited platinum. A nanomanipulation system was used to assemble the parts 'by hand' and platinum deposition was used to weld all elements together. The snowman is mounted on a silicon cantilever from an atomic force microscope whose sharp tip 'feels' surfaces creating topographic surveys at almost atomic
The techniques used to create the Nano scale snowman are employed by NPL:
To make and fine tune Atomic Force Microscope cantilevers for measuring surface topography.
To manufacture nano scale SQUIDs (Superconducting Quantum Interference Devices) for a wide range of future metrological applications including spintronics, single particle detection, NEMS and quantum information processing.
To measure magnetic properties of very small magnetic systems using quantum hall probes.
A video of how the snowman was made is can be found at the NPL site and on YouTube at: http://www.youtube.com/watch?v=LmK8ec9MruM&feature=related
