Anisotropic etching by electrospray for reduction in parasitic resistance of organic field-effect transistors

Abstract

Productive manufacturing that uses a roll-to-roll process, called printed electronics, is highly demanded for low-cost, large-area, and high-speed fabrication of organic devices. However, although most studies on the printing process have been focused on the deposition of films, few studies are reported on solution methods for anisotropic etching that are compatible with the printing process. Studying anisotropic etching by using a wet process is a matter of great importance for the further development of printed electronics. Here, we conduct anisotropic etching by using an electrospray method, one of the wet processes, on an underlying active layer beneath source and drain electrodes and demonstrate a reduction in the parasitic resistance of organic field-effect transistors. The same equipment for the etching as the deposition of films was consistently used. Therefore, this study will pave the way for sophisticating printed electronics. • TIPS pentacene/PMMA blend films and PMMA etch masks were prepared by ESD. • We conducted anisotropic etching by using an electrospray method (a wet process). • Underlying TIPS pentacene beneath source/drain electrodes was selectively etched. • We demonstrated a clear reduction in the parasitic resistance of top-contact OFETs. • The same ESD system for the etching as the deposition of films was consistently used.