High-reolution imprint and soft lithography for patterning self-assembling systems

Abstract

This thesis contributes to the continuous development of patterning strategies in several different areas of unconventional nanofabrication. A series of soft lithography approaches (microcontact printing, nanomolding in capillaries), nanoimprint lithography (NIL), and capillary force lithography (CFL) combined with different surface chemistry have been used to pattern or process different self-assembling systems (e.g. self-assembled monolayers, nanoparticles, (bio)molecules, and polymers) on surfaces. A focus is on high resolution and high materials versatility. In Chapter 3, the formation of bifunctional, chemically patterned flat PDMS stamps improved the compatibility of the PDMS with polar inks by having hydrophilic patterns on the PDMS surface. In chapter 4 and 5, the combination of nanoimprint lithography or capillary force lithography with flat stamp concept opens new ways to fabricate chemical patterns on flat PDMS and improves the printing resolution down to sub-100 nm. In chapter 6 and 7, the use of a hybrid PDMS nanomold as a template for a wet lithography approach has created a simple but powerful tool to pattern different kinds of material at the nanoscale. These high-resolution soft lithography approaches developed in this thesis are ready to be used in normal research labs as tools to pattern different molecules or nanomaterials to functional nanostructures especially, when combined with the large chemical versatility of soft lithography. I also believe these tools are valuable to fabricate future nano-electronic or bio-sensing devices.