Fabrication of GaAs nanostructures with a scanning tunneling microscope

A method for fabricating GaAs nanostructures with a scanning tunneling microscope (STM) is presented. Utilizing a previously developed Si STM fabrication technique, the STM is used to pattern a thin (5 nm) epitaxial Si layer which is grown on GaAs. The patterned Si layer is used as a mask for wet etching the GaAs. This fabrication technique is quite general and should extend to other material systems provided a surface epitaxial Si layer can be grown.