Submicrometer-sized polystyrene particles packing on silicon microfabricated substrate

The Packing of submicrometer-sized polystyrene particle within micro-boxes; micrometer-sized squarely recessed pits, was achieved using silicon microfabricated substrates and a simple dipping and pulling-up process. A special phenomenon, cubic packing structures of the particles, was observed when using a micro-box substrate with a few times larger side-length than the particle diameters. Several particle packing structures within different sized micro-boxes were demonstrated, and the relationship between the particle packing structures and micro-box sizes were discussed.