Using molecular monolayers as self-assembled photoresist

The authors investigated the use of a self-assembled monolayer (SAM) of molecules as resist for photolithography. The SAM constitutes an atomically uniform photosensitive layer with the nominal thickness of 1-2 nm. This molecular monolayer can be patterned by selective exposure to UV light. The removal of the molecules was characterized from the surface with x-ray photoelectron spectroscopy (XPS). Various post processing methods was investigated on the surface patterned with molecules including wet etching and polymer self-assembly based on surface energy difference. An organic field effect transistor (OFET) fabricated using the lithography system was presented and discussed the potential for making devices directly with the molecules that participate in the lithography scheme.