Study on nanoscale abrasive interaction between nanoprobe and self-assembled molecular surface for probe-based nanolithography process

Mechano-chemical scanning probe lithography (MC-SPL) is a nanofabrication technique that is based on the nanoscale abrasive interaction between a sharp nanoprobe and an ultrathin organic resist-coated surface. This work reviews the fundamental aspects of the MC-SPL process. The abrasive interaction at the tip-workpiece contact interface that occurs in the MC-SPL process was investigated by experimentally as well as by molecular dynamics simulation. Experimental results showed that severe wear of the tip that can generate just after coming into contact with the sample and the defects on the organic resists lead to the pattern broadening. In addition, the results from the simulation using the tips modeled with various shapes disclosed that the scribed pattern width was largely affected more by the shape of the tip rather than by the tip-surface contact area and thus the severe pattern broadening and large displacement of alkanethiol molecules around the tip could occur in the case of using the tip with large cone angle. It was found that these phenomena were due to the strong van der Waals interactions between the alkanethiol molecules.