Bio-inspired frictional pads made of CNT composites for high temperature process

Abstract

During the assembly process of semiconductors or display devices, silicon wafers or glass substrates, which are usually very thin, large, and fragile, should be carefully handled with high accuracy. Moreover, there should be no surface contamination on the substrates. Thus, bio-inspired mushroom-shaped adhesive pads have strong potential to replace existing techniques such as vacuum suction or electrostatic chucks since dry adhesives enable precise manipulation of various substrates without any surface contamination in a reversible, repeatable, and durable manner. To fabricate mushroom-shaped dry adhesives, poly(dimethyl siloxane) (PDMS) have been widely used because they have favorable mechanical properties such as low elastic modulus and high elongation break, which allows for simple and reliable prototyping. Furthermore, the low elastic modulus of the PDMS allows the replicated structures to make a conformal contact against varying substrates even under low preload and therefore exhibit a high level of adhesion strength. In spite of these advantages, the PDMS shows inherent limitations in maintaining its form and adhesion strength at high temperature (> 200 ℃), which brings restrictions on practical application for various high-temperature manufacturing process. To address this limitation, we suggest bio-inspired adhesive pads using carbon nanotube (CNT) composite which have enhanced durability and stability at high-temperature conditions.