Several techniques have been investigated for creating large-area thin films of diblock copolymers, with well-ordered two-dimensional periodic microstructure on the scale of a few tens of nanometres. Such structures might potentially be used as templates for lithography, at a length scale not easily accessed by electron-beam methods. Using a copolymer with a spherical microdomain structure, we find that it is quite easy to obtain large-area films consisting of a monolayer of spherical domains, arranged on a hexagonal lattice with a lattice constant of 33 nm. Copolymers with cylindrical microstructure typically orient parallel to the substrate and free surface, it has been found that the perpendicular orientation is metastable: if a well- or poorly-ordered film is initially prepared with the cylinders perpendicularto the surface, annealing results in a well-ordered film with the same orientation, with a lattice constant of 27 nm for the polymer used in this study. For both cylinders and spheres, grains measuring typically 30×30 lattice constants are readily obtained.
Polymer Microstructure Thin Film Hexagonal Free Surface
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
This is a preview of subscription content, log in to check access.