Shear-Solvo Defect Annealing of Diblock Copolymer Thin films over Large Area

Abstract

The defects formed during the microphase separation of block copolymers (BCPs) act as obstacles to leaping from a fundamental understanding of BCP self-assembly to a practical level of bottom-up lithography. Several methods have been proposed, such as increasing chain mobility to remove defects; however, they have difficulty maintaining high orientation in a large area. Here we introduce a reliable and facile approach to generate well-ordered 1D array of nanopatterns with low defects density over centimeter square areas. We show that the shear and subsequent solvent vapor annealing effectively remove defects without disturbing the pattern orientations. The grazing incidence small angle X-ray scattering and microscopic defect quantification were performed to reveal the detailed defect annealing process and the superior quality of nanopatterns was further confirmed with X-ray Bragg diffraction measurement providing an opportunity to application of high efficient optoelectronic devices.