Advanced transfer printing methods and their applications to functional surfaces

Transfer printing is a method to transfer homogeneous or heterogeneous materials called ‘inks’ from a donor substrate where they are produced to a receiving substrate where they are utilized via a polymeric stamp. Transfer printing inherently promises the heterogeneous material integration to enable nontrivial functional structures and devices as inks are separately prepared on a donor substrate and assembled on other receiving substrates. However, the current transfer printing still has several areas of improvement to achieve those promises practically: (1) methods to prepare wide range of ink materials into transferrable format; (2) high yield and scalable transfer printing of inks onto receiving substrates regardless of ink-substrate material pair compatibility; (3) processes to fabricate inks with multiple functionalities; (4) polymeric stamp materials with tunable underwater adhesion to add further environmental diversity to transfer printing. In this thesis, advanced transfer printing methods to widen material choices and improve process scalability, and a tunable underwater polymer adhesive are introduced. First, in particular to the material choice, methods to process SU8 and colloidal quantum dot films in transferrable format are designed. Second, for the process scalability, a method to transfer print a larger area patterned silicon membrane in a single step even onto unfavorable receiving substrates such as slippery, structured, or curved surfaces are developed. Third, process protocols to enable double-sided patterned inks with dual functionality such as structural coloration or superhydrophobicity paired with external stimuli responsiveness are invented. Lastly, switchable underwater adhesive properties of a shape memory polymer that is one of common polymeric stamp materials are investigated. Furthermore, these advances in transfer printing are explored to enable heterogeneously assembled functional surfaces with optimized functionalities including droplet manipulation, omniphobicity, liquid filtration, adhesion control, electroluminescence, and aquatic soft robot locomotion.LimitedAuthor requested closed access (OA after 2yrs) in Vireo ETD syste