A single-step process for making nanofluidic channels using electron beam lithography

The science of micro- and nano-fluidics has attracted much interest recently. Parallel to this has been the evolution of applications such as the laboratory-on-a-chip, and recently, the possibility of single molecule detection. In order to realise such applications new fabrication methods are required. In this work, we demonstrate a simple, single-step process using electron-beam lithography to write parallel ribs of cross-linked UV-3 resist. The resist is spun on to a SiO 2 layer on a silicon substrate. If the resist thickness, electron dose, rib width and gap width all lie within a limited range, then the ribs collapse or fold towards each other making a sealed contact at the apex. This action depends on the exploitation of the forces of surface tension and capillarity during the final drying process.