title: Size selective assembly of colloidal particles on a template by directed self-assembly technique.
abstract: We report a simple and effective approach to organize micron- and submicron-sized particles in a size selective manner. This approach utilizes the template assisted directed self-assembly technique. A topographically patterned photoresist surface is fabricated and used to create an ordered array of colloidal particles from their aqueous suspensions. Assembly of particles on this template is then achieved by using a conventional spin coating technique. Feasibility of this technique to form a large area of patterned particle assemblies has been investigated. To arrange the particles on the template, the physical confinement offered by the surface topography must overcome a joint effect of centrifugal force and the hydrophobic nature of the photoresist surface. This concept has been extended to the size selective sorting of colloidal particles. The capability of this technique for sorting and organizing colloidal particles of a particular diameter from a mixture of microspheres is demonstrated.
authors.affiliation: Department of Physics, Faculty of Science, National University of Singapore, 2 Science Drive 3, Singapore.
authors.forename: Binni
authors.initials: B
authors.lastname: Varghese
authors.forename: Fook Chiong
authors.initials: FC
authors.lastname: Cheong
authors.forename: Swaminathan
authors.initials: S
authors.lastname: Sindhu
authors.forename: Ting
authors.initials: T
authors.lastname: Yu
authors.forename: Chwee-Teck
authors.initials: CT
authors.lastname: Lim
authors.forename: Suresh
authors.initials: S
authors.lastname: Valiyaveettil
authors.forename: Chorng-Haur
authors.initials: CH
authors.lastname: Sow
mesh_terms: D003102:Colloids / Q000737:chemistry*; D057927:Hydrophobic and Hydrophilic Interactions; D018625:Microscopy, Atomic Force; D010316:Particle Size; D011137:Polystyrenes / Q000737:chemistry; D012996:Solutions / Q000737:chemistry; D013499:Surface Properties; D014867:Water / Q000737:chemistry*
chemical_list: D003102:Colloids; D011137:Polystyrenes; D012996:Solutions; D014867:Water