Dip coating cooperated with stepped rotating lithography to fabricate rigid microstructures onto a metal roller

In recent years, roller imprinting has been considered as the most efficient technique for replicating microstructures onto polymeric substrate. However, the preparation of roller is still a challenge. This paper reports an effective method of directly fabricating microstructures on metal rollers; the process includes dip coating of the photoresist on the roller, stepped rotating lithography and electroless nickel plating. The facilities for dip coating and stepped rotating lithography have been implemented. The positive photoresist (EPG510) is first uniformly coated on the roller surface using dip coating process. The microstructures on the roller can be then defined by using stepped rotating photolithography with a glass mask, followed by electroless nickel plating. Rigid microstructured roller can be obtained. The experimental results show that the dip-coated film thickness on the roller increases with the withdrawal velocity of the roller from the resin bath. The coated photoresist on the roller surface is uniform. The microstructures have been successfully fabricated onto the metal roller using the stepped rotating lithography; the rigid nickel microstructures with various pitches on metal roller can be fabricated by adjusting the rotating degree of stepped rotating lithography.