Long Range 3 D Scanning Tunnelling Microscopy

State of the art scanning tunnelling microscopes (STMs) detect surfaces contactlessly with a needle-like probe and use piezo-elements for realizing relative movements between probe and specimen. This leads to a 2.5 D characteristic with a very small measuring range of typically 100 μm × 100 μm × 10 μm. To overcome these deficiencies a new STM probing system without moving parts has been designed, set-up with a special probing element and integrated into a laser-interferometrically controlled long-range nanopositioning unit. The resulting system features a measuring range of up to 25 mm × 25 mm × 5 mm at a principal resolution of 0.1 nm and is capable of true 3D measurements.