Abstract
Electron beam lithography is used to fabricate two-metal electrode tip-shaped structures. The distance between the tips is continuously controlled to be between 5 and 70 nm. The electron beam lithography process is robust and the tip separation is well controlled in the sense that the smallest distance between the tips is a consequence of the design and not a consequence of randomly distributed metal spots around the tip area. Interest in these structures is due to the fact that they can be used to fabricate rectifiers, working with single molecule, designed to exhibit semiconductor properties.