Rapid Large-Scale Patterning

See allHide authors and affiliations

Science  27 Apr 2001:
Vol. 292, Issue 5517, pp. 603-605
DOI: 10.1126/science.292.5517.603e

Block copolymers readily phase-separate to form microdomains, a process used to create templates for nanolithography, for instance. Getting neighboring domains to coalign is a difficult but necessary step for the formation of large templates. A number of tricks have been used to overcome this problem, but the methods used to date tend to be slow or limited to thin films.

Park et al. have devised a new approach that allows for the rapid production of aligned lamellar and cylindrical microdomains of amorphous diblock copolymers. A thin diblock polymer film was placed on a carbon-coated glass slide, and a solvent (either benzoic acid or anthracene) was placed underneath and sandwiched with a second glass slide. The sample was heated, which caused the polymer to dissolve into the organic solvent. As the sample was cooled directionally, the solvent crystallized in one particular crystal growth direction, and above it the polymer microdomains aligned in the same direction. The solvent was then washed away, leaving the domain structure of the diblock copolymer intact. Growth rates on the order of 2 millimeters per second were achieved, and well-aligned parallel lamellae were observed to extend over regions larger than 50 square microns. — MSL

Macromolecules34, 2602 (2001).

Navigate This Article