Modeling Surface Interactions for Block Copolymers and Polymer Brushes under Soft Confinement*

The surface interaction is one of the most important factors that control the nanostructures formed by block copolymers/polymer brushes under soft confinement. In this talk, we introduce a simplified model for surface interactions where the role of soft substrates is decomposed into two independent contributions: the surface preference and the surface softness. Soft substrates are modeled by polymers grated onto hard walls. Their structures on both repulsive and attractive walls are studied by SCFT.^[1] Based on this model, we perform a numerical analysis of the stability competition between perpendicular and parallel lamellae of symmetric diblock copolymers on substrates modified by homopolymers.^[2] The effects of the surface preference and the surface softness on the alignment of lamellar domains are carefully examined. Applications of this model on understanding the defect removal process in DSA of block copolymer thin films are also demonstrated.^[3]
[1] YX Liu; HD Zhang; Chinese J. Polym. Sci., 2018, 36, 1047.
[2] JQ Song; YX Liu; HD Zhang; J. Chem. Phys., 2016, 145, 214902.
[3] JQ Song; YX Liu; HD Zhang; Acta Polym. Sin., 2018, 12, 1548.