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Direct Immersion Annealing of Thin Block Copolymer Films



Jack F. Douglas, Alamgir Karim, Arvind Arvind Modi1, Sarang Bhaway, Bryan D. Vogt, Abdullah Al-Enizi, Ahmed Elzatahry, Ashutosh Sharma


We demonstrate that direct immersion annealing (DIA) greatly enhances the rate at which block copolymer (BCP) films order into stable morphologies when the BCP films are immersed in carefully selected mixtures of good and marginal solvents that can impart enhanced polymer mobility, while at the same time preventing film dissolution. This form of DIA is compatible with roll-to-roll assembly manufacturing and has distinct advantages over conventional thermal annealing and batch processing solvent-vapor annealing methods in terms of high throughput and commercial suitability. We identify three solvent composition dependent BCP film ordering regimes in DIA, for the weakly interacting polystyrene-polymethylmethacrylate (PS-PMMA) system: rapid short range order, optimal long-range order, and a film instability regime. Kinetic studies in the “optimal long-range order” processing regime as a function of temperature indicate a significant reduction of activation energy for BCP grain growth compared to oven annealing at conventional temperatures, but similar to high temperature oven annealing. An attractive feature of DIA is its robustness to ordering different BCP systems exhibiting spherical, lamellar and cylindrical ordering.
ACS Applied Materials and Interfaces


mixed solvents, direct immersion annealing, block copolymer ordering, kinetics


Douglas, J. , Karim, A. , Arvind, A. , Bhaway, S. , , B. , Al-Enizi, A. , Elzatahry, A. and Sharma, A. (2015), Direct Immersion Annealing of Thin Block Copolymer Films, ACS Applied Materials and Interfaces (Accessed April 18, 2024)
Created September 9, 2015, Updated January 27, 2020