Toward sub-20 nm hybrid nanofabrication by combining the molecular ruler method andelectron beam lithography

Abstract

It is of great interest and importance to develop new nanofabrication processes to fabricatesub-20 nm structures with sub-2 nm resolution for next-generation nanoelectronic devices. Acombination of electron beam lithography (EBL) and a molecular ruler is one of thepromising methods to make these fine structures. Here we successfully develop a hybridmethod to fabricate sub-20 nm nanogap devices at the desired positions with a complexstructure by developing a post-EBL process, which enabled us to avoid damaging themolecular ruler with the high-energy electron beam, and to fully utilize the EBLresolution. It was found that slight etching of the Ti adhesion layer of the parent metal(Pt) by ACT935J solution assisted the removal of molecular rulers, resultingin improved enhancement in the product yield (over 70%) of nanogap devices.