Nanostructuring Conjugated Materials by Lithographically Controlled Wetting

We present a novel fabrication technique, which we termed lithographically controlled wetting. A stamp is placed in contact with a liquid thin film; in this manner, capillary forces drive the liquid to distribute only under the protrusions of the stamp. As the solvent evaporates, the deposited solute forms a pattern on the surface with the same length scale of the stamp. By carefully choosing the experimental conditions, it is possible to downscale the printed features relative to the size of the stamp features by at least a factor 7, viz., several tens of nanometers-wide nanostructures can be fabricated using a stamp with submicrometer features. The process, which is completely general to a variety of soluble materials, is demonstrated to yield nanosized structures of a relevant molecular material, viz., tris-8-hydroxyquinoline-aluminum(III).