Large-scale fabrication of SU-8 polymer micro/ nanoscale nozzle by hot embossing and UV exposure

Abstract Electrohydrodynamic-jet printing (E-jet printing) is a direct-writing technology for manufacturing micro-nano devices. In order to further reduce the inner diameter of the nozzle to improve the printing resolution, a large-scale manufacturing method of an SU-8 polymer micro/nanoscale E-jet nozzle chip by means of a process combining inverse ultraviolet (UV) exposure and hot embossing is proposed. First. a convex nano-mold is made by pouring polydimethylsiloxane (PDMS) on the concave 2D silicon nano-mold. The convex patterns so achieved were transferred as nanochannels in a layer of SU-8 that was hot-embossed by the PDMS mold. After removal from the mold, the 188 nm wide and 80 nm deep SU-8 nanochannels were covered with an SU-8 cover layer to become nozzles, to which the microchannel were add by inverse UV photolithography and development. The method of manufacturing SU-8 polymer micro/ nanoscale E-jet nozzle chips developed in this study will greatly promote the study of the transport properties of nanoscale channels in E-jet nozzles, and enable further development of E-jet based applications.