Soft microcontact printing with force control using microrobotic assembly based templates

In this study, soft microcontact printing with force control using microrobotic assembly based templates is investigated. Polystyrene microparticles are assembled automatically in a 2-D desired pattern on a glass substrate using an atomic force microscope nanoprobe installed on a nanopositioning stage. A force-controlled printing process of the patterned stamp is conducted after making a template and stamp from the assembled microparticles. Aluminum sputtering of the pattern on the glass and ultrasonically removing the microparticles is used to make a template. Soft lithography method is used to mold elastomeric polymers on the template to make a stamp. The stamp is inked and printed with a force-controlled system on a Petri dish substrate. Depending on the particle size and contact force, a smaller micro or nanometer size pattern can be formed. Since the spherical patterns on the stamp collapse due to the interfacial contact force, force-controlled microcontact printing is crucial. Using a fluorescent protein for inking the stamps enables the fluorescent imaging of the imprints. Preliminary experiments using 5 mum and 10 mum diameter polystyrene particles showed the feasibility of our technique. Thus, it is possible to get nanopatterns using assembled microparticle based stamps in high volumes