Development of optical‐driven nanoneedles using SU‐8 nanofabrication

Abstract We developed an optical‐driven nanoneedle that is operated in aqueous solution by two focused laser beams. A nanoneedle tool consists of 2 μm‐sized structures for optical trapping and a nanoneedle having 200 nm width and 20 μm length. Nanoneedle tools are fabricated with single ultraviolet (UV) lithography of SU‐8 photoresist with highly scalable manner. We evaluated the conditions of the lithography processes: rinse, hard bake and post exposure bake (PEB) that determine the shape of the nanoneedles and recovery rate. We demonstrated the trapping of a nanoneedle tool to verify the manipulation of the position and the orientation. Nanoneedle tools have an advantage in the use of closed microchanells, which can lead to the applications including delivery and extraction of substances inside single cells and pinpoint molecular processing of biomolecules. In this paper, we report on the fabrication process of the nanoneedle tools and the demonstration of the manipulation.