Atomic-scale patterning of hydrogen terminated Ge(001) by scanningtunneling microscopy

In this paper we demonstrate atomic-scale lithography on hydrogenterminated Ge(001). The lithographic patterns were obtained byselectively desorbing hydrogen atoms from a H resist layer adsorbed ona clean, atomically flat Ge(001) surface with a scanning tunnelingmicroscope tip operating in ultra-high vacuum. The influence of thetip-to-sample bias on the lithographic process have been investigated.Lithographic patterns with feature-sizes from 200 to 1.8 nm have beenachieved by varying the tip-to-sample bias. These results open up thepossibility of a scanning-probe lithography approach to the fabricationof future atomic-scale devices in germanium