BioMaDe

Soft Nanolithography

This technology involves making high-resolution surface relief textures in film layers such as polymers deposited on substrates. The textures are formed by exposing a thin polymer layer to a temperature gradient perpendicular to its surface, which generates forces that destabilize the film. In a small gap between two plates that are set to different temperatures, this leads to the formation of a columnar array or equidistant stripes. This pattern formation process can be controlled by a lateral variation of the applied temperature gradient, provided for example by a topographically patterned ´master´ plate. This way, structures with lateral feature sizes ranging from 100 nm to several micrometers can be reliably replicated into a polymer film. It is believed that this technology could be used to make iridescent patterns by creating tall regular polymer structures that refract light. In this it would mimic certain natural structures found e.g. on the wings of tropical butterflies and moths. The underlying structures, geometry and physics of these have only just been established: artificially structured films were made on very small surface areas only. The technology that Biomade is now developing is based on structured surfaces found in nature, with properties such as colored appearance, the reduced reflection of light, reversible adhesion, and self-cleaning abilities.