Local electrophoretic deposition using patterned counter electrode

Abstract

Many researchers have fabricated micro-patterned films by combining electrophoretic deposition (EPD) with photolithography. However, photolithography needs a complicated process including coating of photoresist and removal of the residue. In this study, we showed that it is possible to simply produce electrophoretic pattern by AC EPD and patterned counter electrode. It is a well-known fact that the use of AC electric field inhibits the formation of bubbles by water electrolysis in aqueous suspension and makes the deposits smooth. In addition to this effect, we demonstrated that AC electric field was suitable to fabricate micro-patterned films because frequency is a key factor to improve resolution of pattern. Also, we investigated effect of different parameters such as deposition time and particle concentration on deposition pattern. The electrophoretic pattern was obtained by adjusting process parameters and its size was similar to the counter electrode. Furthermore, we demonstrated that 3D complex patterned composite by placing one film on another film. We believe that this method provides a large processing window in terms of electrophoretic patterning