Nanometer scale structuring of silicon by direct indentation

Shallow indentations with diameters of 2–10 nm have been made directly in clean Si(110) and Si(001) surfaces using the W tip of a scanning tunneling microscope. The shape of the holes formed depends on the shape of the tip and is not influenced by the presence or absence of a tunneling current during the indentation process. The sharpness of the tip is not degraded by the intimate tip–sample contact. Arbitrary line and bit patterns can therefore be written and read repeatedly using the same tip.