| 초록 |
A challenge in nanotechnology is controllling self-assembling systems to enable a specific functionality. Self-organizing bock copolymers (BCPs) offer a rich variety of periodic nanoscale patterns. BCPs consist of two or more chemically different polymer chains joined covalently at their ends. Due to the positive (non-favorable) enthalpy and small entropy of mixing, dissimilar blocks tend to microphase separate into well-ordered arrays of domains, classically termed microdomains. The size scale of these microdomains, due to the connectivity of the blocks, is limited to molecular dimensions and, nence, are tens of nanometers in size or less. The self-assembly of BCPs into well-defined morphologies has opened numerous applications ranging from drug delivery to structural materials. In contrast to the bulk, the morphology of amorphous BCP thin films can be strongly influenced by surface and interfacial interactions and the commensurability between the film thickness, h, and the period of the microdomain morphology, L0. With decreasing film thickness these parameters become increasingly important in defining the morphology. By controlling the orientation and lateral ordering of the BCP microdomains in thin films, unique opportunities in the use of BCPs in materials science (adhesive properties, lubrication, membranes, and coatings), lithography and microfabrication (addressable memory, magnetic storage, insulting foams) and device technologies (light-emitting diodes, photodiodes, and transistors) are beginning to emerge. |
