Dr. Mark Schvartzman
Organization of nanostructures on guiding nanopatterns is a powerful approach to create complex nanomaterials and functional systems from the bottom-up, as well as to manipulate biomolecules in living systems. In this work, nanoimprint lithography with sub-10 nm resolution was used to realize unique guiding platforms for two types of controlled organization in the areas of nanoelectronics and biointerfaces:
(i) A new bottom–up approach for massively parallel deterministic assembly of semiconductor nanowires was demonstrated via surface-guided horizontal growth from nanoimprinted catalyst. The guided growth and the catalyst nanopattern defined the direction and length, and the position of each nanowire, respectively, both with unprecedented precision and yield, without the need for post-growth assembly. Highly ordered nanowire arrays were used for the parallel production of hundreds of nanowire electronic devices, as well as for the integration of nanowires into electronic circuits,such as logic gates and address decoders.
(ii) Ultrahigh resolution nanoimprint was combined with site-selective bioconjugation in order to create biomimetic arrays of individual protein binding sites.The binding sites were arranged in heterogeneous patterns of various geometries and used to explore how the geometric organization of the extracellular matrix (ECM) binding ligand RGD (Arg-Gly-Asp) affects cell adhesion and spreading. Systematic variation of spacing, density and cluster size of individual integrin binding sites was used to elicit different cell behavior and discover the existence of a minimal matrix adhesion unit of 4 ligated site.