Dynamic breath figure template for electrohydrodynamic lithography: Formation of multiscale micro-craters and wells

Abstract

In the rapidly evolving landscape of nanofabrication, developing novel pathways that allow control over micro- and nano-lengthscales is essential for advancing different technological applications. A curable multiscale pattern, consisting of feature sizes ranging from ∼ 3 µm to ∼ 60 µm with periodicity from ∼4 µm to ∼300 µm, fabricated on a deformable elastomeric substrate is demonstrated through a soft lithographic pathway without using any expensive equipment. The modified breath figure lithography has been used in conjunction with micro-contact printing, and UV-plasma treatment to fabricate the patterned substrate suitable for electrohydrodynamic lithography. This integration showcases the adaptability and enhances the scalability and efficiency of the process of breath figure lithography in different fabrication methods. This process has a scope to lower the feature size in each step. Thus, it offers a tool for adjusting wavelength and altering the feature shape and size of the microstructures (micro craters and microwells). This whole process includes the preservation of soft microstructures through rheological petrification. The novelty of this work lies in its experimental techniques within the concept of soft lithographic patterning that solely depends upon conventional processes like microcontact printing, breath figure lithography, elastomeric surface modification, and electrohydrodynamic lithography. Ultimately, four different lengthscales in the feature sizes are achieved using this easy-to-fabricate technique.